rm -rf quota2a quota2b quota2c
	rm -rf tsrc .target_source
	rm -f tclsqlite3$(TEXE)
	rm -f testfixture$(TEXE) test.db
	rm -f sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	rm -f sqlite3.c
	rm -f sqlite3_analyzer$(TEXE) sqlite3_analyzer.c


distclean:	clean
	rm -f config.log config.status libtool Makefile sqlite3.pc

#
# Windows section
#

	rm -rf quota2a quota2b quota2c
	rm -rf tsrc .target_source
	rm -f tclsqlite3$(TEXE)
	rm -f testfixture$(TEXE) test.db
	rm -f sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	rm -f sqlite3.c
	rm -f sqlite3_analyzer$(TEXE) sqlite3_analyzer.c
	rm -f sqlite-output.vsix

distclean:	clean
	rm -f config.log config.status libtool Makefile sqlite3.pc

#
# Windows section
#

USE_NATIVE_LIBPATHS = 0

# Set this non-0 to compile binaries suitable for the WinRT environment.
# This setting does not apply to any binaries that require Tcl to operate
# properly (i.e. the text fixture, etc).
#
FOR_WINRT = 0






# Set this to non-0 to create and use PDBs.
#
SYMBOLS = 1

# Set this to one of the following values to enable various debugging
# features.  Each level includes the debugging options from the previous
................................................................................
# For example, to use the x86 compiler when cross-compiling for x64, a command
# line similar to the following could be used (all on one line):
#
#     nmake /f Makefile.msc
#           "NCC=""%VCINSTALLDIR%\bin\cl.exe"""
#           USE_NATIVE_LIBPATHS=1
#
!IFNDEF NCC


NCC = $(CC)
!ENDIF

# Check for the MSVC runtime library path macro.  Othertise, this
# value will default to the 'lib' directory underneath the MSVC
# installation directory.
#
!IFNDEF NCRTLIBPATH
NCRTLIBPATH = $(VCINSTALLDIR)\lib
!ENDIF



# Check for the Platform SDK library path macro.  Othertise, this
# value will default to the 'lib' directory underneath the Windows
# SDK installation directory (the environment variable used appears
# to be available when using Visual C++ 2008 or later via the
# command line).
#
!IFNDEF NSDKLIBPATH
NSDKLIBPATH = $(WINDOWSSDKDIR)\lib
!ENDIF



# C compiler and options for use in building executables that
# will run on the platform that is doing the build.
#
BCC = $(NCC) -W3

# Check if the native library paths should be used when compiling
................................................................................
# When compiling the library for use in the WinRT environment,
# the following compile-time options must be used as well to
# disable use of Win32 APIs that are not available and to enable
# use of Win32 APIs that are specific to Windows 8 and/or WinRT.
#
!IF $(FOR_WINRT)!=0
TCC = $(TCC) -DSQLITE_OS_WINRT=1

!ENDIF

# Also, we need to dynamically link to the correct MSVC runtime
# when compiling for WinRT (e.g. debug or release) OR if the
# USE_CRT_DLL option is set to force dynamically linking to the
# MSVC runtime library.
#
................................................................................

# If either debugging or symbols are enabled, enable PDBs.
!IF $(DEBUG)>0 || $(SYMBOLS)!=0
LDFLAGS = /DEBUG
!ENDIF

# Start with the Tcl related linker options.

LTLIBPATHS = /LIBPATH:$(TCLLIBDIR)
LTLIBS = $(LIBTCL)


# If ICU support is enabled, add the linker options for it.
!IF $(USE_ICU)!=0
LTLIBPATHS = $(LTLIBPATHS) /LIBPATH:$(ICULIBDIR)
LTLIBS = $(LTLIBS) $(LIBICU)
!ENDIF

................................................................................
	-rmdir /Q/S tsrc
	del /Q .target_source
	del /Q tclsqlite3.exe
	del /Q testfixture.exe testfixture.exp test.db
	del /Q sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	del /Q sqlite3.c
	del /Q sqlite3_analyzer.exe sqlite3_analyzer.exp sqlite3_analyzer.c


#
# Windows section
#
dll: sqlite3.dll

sqlite3.def: libsqlite3.lib

USE_NATIVE_LIBPATHS = 0

# Set this non-0 to compile binaries suitable for the WinRT environment.
# This setting does not apply to any binaries that require Tcl to operate
# properly (i.e. the text fixture, etc).
#
FOR_WINRT = 0

# Set this non-0 to skip attempting to look for and/or link with the Tcl
# runtime library.
#
NO_TCL = 0

# Set this to non-0 to create and use PDBs.
#
SYMBOLS = 1

# Set this to one of the following values to enable various debugging
# features.  Each level includes the debugging options from the previous
................................................................................
# For example, to use the x86 compiler when cross-compiling for x64, a command
# line similar to the following could be used (all on one line):
#
#     nmake /f Makefile.msc
#           "NCC=""%VCINSTALLDIR%\bin\cl.exe"""
#           USE_NATIVE_LIBPATHS=1
#
!IFDEF NCC
NCC = $(NCC:\\=\)
!ELSE
NCC = $(CC)
!ENDIF

# Check for the MSVC runtime library path macro.  Othertise, this
# value will default to the 'lib' directory underneath the MSVC
# installation directory.
#
!IFNDEF NCRTLIBPATH
NCRTLIBPATH = $(VCINSTALLDIR)\lib
!ENDIF

NCRTLIBPATH = $(NCRTLIBPATH:\\=\)

# Check for the Platform SDK library path macro.  Othertise, this
# value will default to the 'lib' directory underneath the Windows
# SDK installation directory (the environment variable used appears
# to be available when using Visual C++ 2008 or later via the
# command line).
#
!IFNDEF NSDKLIBPATH
NSDKLIBPATH = $(WINDOWSSDKDIR)\lib
!ENDIF

NSDKLIBPATH = $(NSDKLIBPATH:\\=\)

# C compiler and options for use in building executables that
# will run on the platform that is doing the build.
#
BCC = $(NCC) -W3

# Check if the native library paths should be used when compiling
................................................................................
# When compiling the library for use in the WinRT environment,
# the following compile-time options must be used as well to
# disable use of Win32 APIs that are not available and to enable
# use of Win32 APIs that are specific to Windows 8 and/or WinRT.
#
!IF $(FOR_WINRT)!=0
TCC = $(TCC) -DSQLITE_OS_WINRT=1
TCC = $(TCC) -DWINAPI_FAMILY=WINAPI_PARTITION_APP
!ENDIF

# Also, we need to dynamically link to the correct MSVC runtime
# when compiling for WinRT (e.g. debug or release) OR if the
# USE_CRT_DLL option is set to force dynamically linking to the
# MSVC runtime library.
#
................................................................................

# If either debugging or symbols are enabled, enable PDBs.
!IF $(DEBUG)>0 || $(SYMBOLS)!=0
LDFLAGS = /DEBUG
!ENDIF

# Start with the Tcl related linker options.
!IF $(NO_TCL)==0
LTLIBPATHS = /LIBPATH:$(TCLLIBDIR)
LTLIBS = $(LIBTCL)
!ENDIF

# If ICU support is enabled, add the linker options for it.
!IF $(USE_ICU)!=0
LTLIBPATHS = $(LTLIBPATHS) /LIBPATH:$(ICULIBDIR)
LTLIBS = $(LTLIBS) $(LIBICU)
!ENDIF

................................................................................
	-rmdir /Q/S tsrc
	del /Q .target_source
	del /Q tclsqlite3.exe
	del /Q testfixture.exe testfixture.exp test.db
	del /Q sqlite3.dll sqlite3.lib sqlite3.exp sqlite3.def
	del /Q sqlite3.c
	del /Q sqlite3_analyzer.exe sqlite3_analyzer.exp sqlite3_analyzer.c
	del /Q sqlite-output.vsix

#
# Windows section
#
dll: sqlite3.dll

sqlite3.def: libsqlite3.lib

        { { $as_echo "$as_me:$LINENO: error: ${with_tclconfig} directory doesn't contain tclConfig.sh" >&5
$as_echo "$as_me: error: ${with_tclconfig} directory doesn't contain tclConfig.sh" >&2;}
   { (exit 1); exit 1; }; }
      fi
    fi

    # Start autosearch by asking tclsh

    if test x"$cross_compiling" = xno; then
      for i in `echo 'puts stdout $auto_path' | ${TCLSH_CMD}`
      do
        if test -f "$i/tclConfig.sh" ; then
          ac_cv_c_tclconfig="$i"
          break
        fi
      done

    fi

    # then check for a private Tcl installation
    if test x"${ac_cv_c_tclconfig}" = x ; then
      for i in \
            ../tcl \
            `ls -dr ../tcl[8-9].[0-9].[0-9]* 2>/dev/null` \

        { { $as_echo "$as_me:$LINENO: error: ${with_tclconfig} directory doesn't contain tclConfig.sh" >&5
$as_echo "$as_me: error: ${with_tclconfig} directory doesn't contain tclConfig.sh" >&2;}
   { (exit 1); exit 1; }; }
      fi
    fi

    # Start autosearch by asking tclsh
    if test x"${ac_cv_c_tclconfig}" = x ; then
      if test x"$cross_compiling" = xno; then
        for i in `echo 'puts stdout $auto_path' | ${TCLSH_CMD}`
        do
          if test -f "$i/tclConfig.sh" ; then
            ac_cv_c_tclconfig="$i"
            break
          fi
        done
      fi
    fi

    # then check for a private Tcl installation
    if test x"${ac_cv_c_tclconfig}" = x ; then
      for i in \
            ../tcl \
            `ls -dr ../tcl[8-9].[0-9].[0-9]* 2>/dev/null` \

        ac_cv_c_tclconfig=`(cd ${with_tclconfig}; pwd)`
      else
        AC_MSG_ERROR([${with_tclconfig} directory doesn't contain tclConfig.sh])
      fi
    fi

    # Start autosearch by asking tclsh

    if test x"$cross_compiling" = xno; then
      for i in `echo 'puts stdout $auto_path' | ${TCLSH_CMD}`
      do
        if test -f "$i/tclConfig.sh" ; then
          ac_cv_c_tclconfig="$i"
          break
        fi
      done

    fi

    # then check for a private Tcl installation
    if test x"${ac_cv_c_tclconfig}" = x ; then
      for i in \
            ../tcl \
            `ls -dr ../tcl[[8-9]].[[0-9]].[[0-9]]* 2>/dev/null` \

        ac_cv_c_tclconfig=`(cd ${with_tclconfig}; pwd)`
      else
        AC_MSG_ERROR([${with_tclconfig} directory doesn't contain tclConfig.sh])
      fi
    fi

    # Start autosearch by asking tclsh
    if test x"${ac_cv_c_tclconfig}" = x ; then
      if test x"$cross_compiling" = xno; then
        for i in `echo 'puts stdout $auto_path' | ${TCLSH_CMD}`
        do
          if test -f "$i/tclConfig.sh" ; then
            ac_cv_c_tclconfig="$i"
            break
          fi
        done
      fi
    fi

    # then check for a private Tcl installation
    if test x"${ac_cv_c_tclconfig}" = x ; then
      for i in \
            ../tcl \
            `ls -dr ../tcl[[8-9]].[[0-9]].[[0-9]]* 2>/dev/null` \

	rm -f testloadext.dll libtestloadext.so
	rm -f amalgamation-testfixture amalgamation-testfixture.exe
	rm -f fts3-testfixture fts3-testfixture.exe
	rm -f testfixture testfixture.exe
	rm -f threadtest3 threadtest3.exe
	rm -f sqlite3.c fts?amal.c tclsqlite3.c
	rm -f sqlite3_analyzer sqlite3_analyzer.exe sqlite3_analyzer.c

	rm -f testloadext.dll libtestloadext.so
	rm -f amalgamation-testfixture amalgamation-testfixture.exe
	rm -f fts3-testfixture fts3-testfixture.exe
	rm -f testfixture testfixture.exe
	rm -f threadtest3 threadtest3.exe
	rm -f sqlite3.c fts?amal.c tclsqlite3.c
	rm -f sqlite3_analyzer sqlite3_analyzer.exe sqlite3_analyzer.c
	rm -f sqlite-output.vsix

      ** side-effect of the CREATE TABLE statement is to leave the rootpage 
      ** of the new table in register pParse->regRoot. This is important 
      ** because the OpenWrite opcode below will be needing it. */
      sqlite3NestedParse(pParse,
          "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
      );
      aRoot[i] = pParse->regRoot;
      aCreateTbl[i] = 1;
    }else{
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
................................................................................
  int mxSample;
  int n;

  UNUSED_PARAMETER(argc);
  nRow = (tRowcnt)sqlite3_value_int64(argv[0]);
  mxSample = sqlite3_value_int(argv[1]);
  n = sizeof(*p) + sizeof(p->a[0])*mxSample;
  p = sqlite3_malloc( n );
  if( p==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }
  memset(p, 0, n);
  p->a = (struct Stat3Sample*)&p[1];
  p->nRow = nRow;
  p->mxSample = mxSample;
  p->nPSample = p->nRow/(mxSample/3+1) + 1;
  sqlite3_randomness(sizeof(p->iPrn), &p->iPrn);
  sqlite3_result_blob(context, p, sizeof(p), sqlite3_free);
}

      ** side-effect of the CREATE TABLE statement is to leave the rootpage 
      ** of the new table in register pParse->regRoot. This is important 
      ** because the OpenWrite opcode below will be needing it. */
      sqlite3NestedParse(pParse,
          "CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
      );
      aRoot[i] = pParse->regRoot;
      aCreateTbl[i] = OPFLAG_P2ISREG;
    }else{
      /* The table already exists. If zWhere is not NULL, delete all entries 
      ** associated with the table zWhere. If zWhere is NULL, delete the
      ** entire contents of the table. */
      aRoot[i] = pStat->tnum;
      sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
      if( zWhere ){
................................................................................
  int mxSample;
  int n;

  UNUSED_PARAMETER(argc);
  nRow = (tRowcnt)sqlite3_value_int64(argv[0]);
  mxSample = sqlite3_value_int(argv[1]);
  n = sizeof(*p) + sizeof(p->a[0])*mxSample;
  p = sqlite3MallocZero( n );
  if( p==0 ){
    sqlite3_result_error_nomem(context);
    return;
  }

  p->a = (struct Stat3Sample*)&p[1];
  p->nRow = nRow;
  p->mxSample = mxSample;
  p->nPSample = p->nRow/(mxSample/3+1) + 1;
  sqlite3_randomness(sizeof(p->iPrn), &p->iPrn);
  sqlite3_result_blob(context, p, sizeof(p), sqlite3_free);
}

    );
    p = 0;
  }else {
    /* Allocate space for a new sqlite3_backup object...
    ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
    ** call to sqlite3_backup_init() and is destroyed by a call to
    ** sqlite3_backup_finish(). */
    p = (sqlite3_backup *)sqlite3_malloc(sizeof(sqlite3_backup));
    if( !p ){
      sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
    }
  }

  /* If the allocation succeeded, populate the new object. */
  if( p ){
    memset(p, 0, sizeof(sqlite3_backup));
    p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
    p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
    p->pDestDb = pDestDb;
    p->pSrcDb = pSrcDb;
    p->iNext = 1;
    p->isAttached = 0;

    );
    p = 0;
  }else {
    /* Allocate space for a new sqlite3_backup object...
    ** EVIDENCE-OF: R-64852-21591 The sqlite3_backup object is created by a
    ** call to sqlite3_backup_init() and is destroyed by a call to
    ** sqlite3_backup_finish(). */
    p = (sqlite3_backup *)sqlite3MallocZero(sizeof(sqlite3_backup));
    if( !p ){
      sqlite3Error(pDestDb, SQLITE_NOMEM, 0);
    }
  }

  /* If the allocation succeeded, populate the new object. */
  if( p ){

    p->pSrc = findBtree(pDestDb, pSrcDb, zSrcDb);
    p->pDest = findBtree(pDestDb, pDestDb, zDestDb);
    p->pDestDb = pDestDb;
    p->pSrcDb = pSrcDb;
    p->iNext = 1;
    p->isAttached = 0;

  int rc = -1;
  int i, nx, pc, op;
  void *pTmpSpace;

  /* Allocate the Bitvec to be tested and a linear array of
  ** bits to act as the reference */
  pBitvec = sqlite3BitvecCreate( sz );
  pV = sqlite3_malloc( (sz+7)/8 + 1 );
  pTmpSpace = sqlite3_malloc(BITVEC_SZ);
  if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;
  memset(pV, 0, (sz+7)/8 + 1);

  /* NULL pBitvec tests */
  sqlite3BitvecSet(0, 1);
  sqlite3BitvecClear(0, 1, pTmpSpace);

  /* Run the program */
  pc = 0;

  int rc = -1;
  int i, nx, pc, op;
  void *pTmpSpace;

  /* Allocate the Bitvec to be tested and a linear array of
  ** bits to act as the reference */
  pBitvec = sqlite3BitvecCreate( sz );
  pV = sqlite3MallocZero( (sz+7)/8 + 1 );
  pTmpSpace = sqlite3_malloc(BITVEC_SZ);
  if( pBitvec==0 || pV==0 || pTmpSpace==0  ) goto bitvec_end;


  /* NULL pBitvec tests */
  sqlite3BitvecSet(0, 1);
  sqlite3BitvecClear(0, 1, pTmpSpace);

  /* Run the program */
  pc = 0;

** If aOvflSpace is set to a null pointer, this function returns 
** SQLITE_NOMEM.
*/
static int balance_nonroot(
  MemPage *pParent,               /* Parent page of siblings being balanced */
  int iParentIdx,                 /* Index of "the page" in pParent */
  u8 *aOvflSpace,                 /* page-size bytes of space for parent ovfl */
  int isRoot                      /* True if pParent is a root-page */

){
  BtShared *pBt;               /* The whole database */
  int nCell = 0;               /* Number of cells in apCell[] */
  int nMaxCells = 0;           /* Allocated size of apCell, szCell, aFrom. */
  int nNew = 0;                /* Number of pages in apNew[] */
  int nOld;                    /* Number of pages in apOld[] */
  int i, j, k;                 /* Loop counters */
................................................................................
  ** way, the remainder of the function does not have to deal with any
  ** overflow cells in the parent page, since if any existed they will
  ** have already been removed.
  */
  i = pParent->nOverflow + pParent->nCell;
  if( i<2 ){
    nxDiv = 0;
    nOld = i+1;
  }else{
    nOld = 3;

    if( iParentIdx==0 ){                 
      nxDiv = 0;
    }else if( iParentIdx==i ){
      nxDiv = i-2;
    }else{

      nxDiv = iParentIdx-1;
    }
    i = 2;
  }

  if( (i+nxDiv-pParent->nOverflow)==pParent->nCell ){
    pRight = &pParent->aData[pParent->hdrOffset+8];
  }else{
    pRight = findCell(pParent, i+nxDiv-pParent->nOverflow);
  }
  pgno = get4byte(pRight);
  while( 1 ){
................................................................................
    int r;              /* Index of right-most cell in left sibling */
    int d;              /* Index of first cell to the left of right sibling */

    r = cntNew[i-1] - 1;
    d = r + 1 - leafData;
    assert( d<nMaxCells );
    assert( r<nMaxCells );

    while( szRight==0 || szRight+szCell[d]+2<=szLeft-(szCell[r]+2) ){

      szRight += szCell[d] + 2;
      szLeft -= szCell[r] + 2;
      cntNew[i-1]--;
      r = cntNew[i-1] - 1;
      d = r + 1 - leafData;
    }
    szNew[i] = szRight;
................................................................................
      pNew = apNew[i] = apOld[i];
      apOld[i] = 0;
      rc = sqlite3PagerWrite(pNew->pDbPage);
      nNew++;
      if( rc ) goto balance_cleanup;
    }else{
      assert( i>0 );
      rc = allocateBtreePage(pBt, &pNew, &pgno, pgno, 0);
      if( rc ) goto balance_cleanup;
      apNew[i] = pNew;
      nNew++;

      /* Set the pointer-map entry for the new sibling page. */
      if( ISAUTOVACUUM ){
        ptrmapPut(pBt, pNew->pgno, PTRMAP_BTREE, pParent->pgno, &rc);
................................................................................
    for(i=0; i<nCell; i++){
      int isDivider = 0;
      while( i==iNextOld ){
        /* Cell i is the cell immediately following the last cell on old
        ** sibling page j. If the siblings are not leaf pages of an
        ** intkey b-tree, then cell i was a divider cell. */
        assert( j+1 < ArraySize(apCopy) );

        pOld = apCopy[++j];
        iNextOld = i + !leafData + pOld->nCell + pOld->nOverflow;
        if( pOld->nOverflow ){
          nOverflow = pOld->nOverflow;
          iOverflow = i + !leafData + pOld->aiOvfl[0];
        }
        isDivider = !leafData;  
................................................................................
          ** different page). Once this subsequent call to balance_nonroot() 
          ** has completed, it is safe to release the pSpace buffer used by
          ** the previous call, as the overflow cell data will have been 
          ** copied either into the body of a database page or into the new
          ** pSpace buffer passed to the latter call to balance_nonroot().
          */
          u8 *pSpace = sqlite3PageMalloc(pCur->pBt->pageSize);
          rc = balance_nonroot(pParent, iIdx, pSpace, iPage==1);
          if( pFree ){
            /* If pFree is not NULL, it points to the pSpace buffer used 
            ** by a previous call to balance_nonroot(). Its contents are
            ** now stored either on real database pages or within the 
            ** new pSpace buffer, so it may be safely freed here. */
            sqlite3PageFree(pFree);
          }
................................................................................
      }
    }
  }

  pBt->btsFlags &= ~BTS_NO_WAL;
  return rc;
}

** If aOvflSpace is set to a null pointer, this function returns 
** SQLITE_NOMEM.
*/
static int balance_nonroot(
  MemPage *pParent,               /* Parent page of siblings being balanced */
  int iParentIdx,                 /* Index of "the page" in pParent */
  u8 *aOvflSpace,                 /* page-size bytes of space for parent ovfl */
  int isRoot,                     /* True if pParent is a root-page */
  int bBulk                       /* True if this call is part of a bulk load */
){
  BtShared *pBt;               /* The whole database */
  int nCell = 0;               /* Number of cells in apCell[] */
  int nMaxCells = 0;           /* Allocated size of apCell, szCell, aFrom. */
  int nNew = 0;                /* Number of pages in apNew[] */
  int nOld;                    /* Number of pages in apOld[] */
  int i, j, k;                 /* Loop counters */
................................................................................
  ** way, the remainder of the function does not have to deal with any
  ** overflow cells in the parent page, since if any existed they will
  ** have already been removed.
  */
  i = pParent->nOverflow + pParent->nCell;
  if( i<2 ){
    nxDiv = 0;

  }else{

    assert( bBulk==0 || bBulk==1 );
    if( iParentIdx==0 ){                 
      nxDiv = 0;
    }else if( iParentIdx==i ){
      nxDiv = i-2+bBulk;
    }else{
      assert( bBulk==0 );
      nxDiv = iParentIdx-1;
    }
    i = 2-bBulk;
  }
  nOld = i+1;
  if( (i+nxDiv-pParent->nOverflow)==pParent->nCell ){
    pRight = &pParent->aData[pParent->hdrOffset+8];
  }else{
    pRight = findCell(pParent, i+nxDiv-pParent->nOverflow);
  }
  pgno = get4byte(pRight);
  while( 1 ){
................................................................................
    int r;              /* Index of right-most cell in left sibling */
    int d;              /* Index of first cell to the left of right sibling */

    r = cntNew[i-1] - 1;
    d = r + 1 - leafData;
    assert( d<nMaxCells );
    assert( r<nMaxCells );
    while( szRight==0 
       || (!bBulk && szRight+szCell[d]+2<=szLeft-(szCell[r]+2)) 
    ){
      szRight += szCell[d] + 2;
      szLeft -= szCell[r] + 2;
      cntNew[i-1]--;
      r = cntNew[i-1] - 1;
      d = r + 1 - leafData;
    }
    szNew[i] = szRight;
................................................................................
      pNew = apNew[i] = apOld[i];
      apOld[i] = 0;
      rc = sqlite3PagerWrite(pNew->pDbPage);
      nNew++;
      if( rc ) goto balance_cleanup;
    }else{
      assert( i>0 );
      rc = allocateBtreePage(pBt, &pNew, &pgno, (bBulk ? 1 : pgno), 0);
      if( rc ) goto balance_cleanup;
      apNew[i] = pNew;
      nNew++;

      /* Set the pointer-map entry for the new sibling page. */
      if( ISAUTOVACUUM ){
        ptrmapPut(pBt, pNew->pgno, PTRMAP_BTREE, pParent->pgno, &rc);
................................................................................
    for(i=0; i<nCell; i++){
      int isDivider = 0;
      while( i==iNextOld ){
        /* Cell i is the cell immediately following the last cell on old
        ** sibling page j. If the siblings are not leaf pages of an
        ** intkey b-tree, then cell i was a divider cell. */
        assert( j+1 < ArraySize(apCopy) );
        assert( j+1 < nOld );
        pOld = apCopy[++j];
        iNextOld = i + !leafData + pOld->nCell + pOld->nOverflow;
        if( pOld->nOverflow ){
          nOverflow = pOld->nOverflow;
          iOverflow = i + !leafData + pOld->aiOvfl[0];
        }
        isDivider = !leafData;  
................................................................................
          ** different page). Once this subsequent call to balance_nonroot() 
          ** has completed, it is safe to release the pSpace buffer used by
          ** the previous call, as the overflow cell data will have been 
          ** copied either into the body of a database page or into the new
          ** pSpace buffer passed to the latter call to balance_nonroot().
          */
          u8 *pSpace = sqlite3PageMalloc(pCur->pBt->pageSize);
          rc = balance_nonroot(pParent, iIdx, pSpace, iPage==1, pCur->hints);
          if( pFree ){
            /* If pFree is not NULL, it points to the pSpace buffer used 
            ** by a previous call to balance_nonroot(). Its contents are
            ** now stored either on real database pages or within the 
            ** new pSpace buffer, so it may be safely freed here. */
            sqlite3PageFree(pFree);
          }
................................................................................
      }
    }
  }

  pBt->btsFlags &= ~BTS_NO_WAL;
  return rc;
}

/*
** set the mask of hint flags for cursor pCsr. Currently the only valid
** values are 0 and BTREE_BULKLOAD.
*/
void sqlite3BtreeCursorHints(BtCursor *pCsr, unsigned int mask){
  assert( mask==BTREE_BULKLOAD || mask==0 );
  pCsr->hints = mask;
}

#define BTREE_FILE_FORMAT         2
#define BTREE_DEFAULT_CACHE_SIZE  3
#define BTREE_LARGEST_ROOT_PAGE   4
#define BTREE_TEXT_ENCODING       5
#define BTREE_USER_VERSION        6
#define BTREE_INCR_VACUUM         7







int sqlite3BtreeCursor(
  Btree*,                              /* BTree containing table to open */
  int iTable,                          /* Index of root page */
  int wrFlag,                          /* 1 for writing.  0 for read-only */
  struct KeyInfo*,                     /* First argument to compare function */
  BtCursor *pCursor                    /* Space to write cursor structure */
);
................................................................................

char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
struct Pager *sqlite3BtreePager(Btree*);

int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
void sqlite3BtreeCacheOverflow(BtCursor *);
void sqlite3BtreeClearCursor(BtCursor *);

int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);


#ifndef NDEBUG
int sqlite3BtreeCursorIsValid(BtCursor*);
#endif

#ifndef SQLITE_OMIT_BTREECOUNT
int sqlite3BtreeCount(BtCursor *, i64 *);

#define BTREE_FILE_FORMAT         2
#define BTREE_DEFAULT_CACHE_SIZE  3
#define BTREE_LARGEST_ROOT_PAGE   4
#define BTREE_TEXT_ENCODING       5
#define BTREE_USER_VERSION        6
#define BTREE_INCR_VACUUM         7

/*
** Values that may be OR'd together to form the second argument of an
** sqlite3BtreeCursorHints() call.
*/
#define BTREE_BULKLOAD 0x00000001

int sqlite3BtreeCursor(
  Btree*,                              /* BTree containing table to open */
  int iTable,                          /* Index of root page */
  int wrFlag,                          /* 1 for writing.  0 for read-only */
  struct KeyInfo*,                     /* First argument to compare function */
  BtCursor *pCursor                    /* Space to write cursor structure */
);
................................................................................

char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
struct Pager *sqlite3BtreePager(Btree*);

int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
void sqlite3BtreeCacheOverflow(BtCursor *);
void sqlite3BtreeClearCursor(BtCursor *);

int sqlite3BtreeSetVersion(Btree *pBt, int iVersion);
void sqlite3BtreeCursorHints(BtCursor *, unsigned int mask);

#ifndef NDEBUG
int sqlite3BtreeCursorIsValid(BtCursor*);
#endif

#ifndef SQLITE_OMIT_BTREECOUNT
int sqlite3BtreeCount(BtCursor *, i64 *);

  u8 wrFlag;                /* True if writable */
  u8 atLast;                /* Cursor pointing to the last entry */
  u8 validNKey;             /* True if info.nKey is valid */
  u8 eState;                /* One of the CURSOR_XXX constants (see below) */
#ifndef SQLITE_OMIT_INCRBLOB
  u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
#endif

  i16 iPage;                            /* Index of current page in apPage */
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
};

/*
** Potential values for BtCursor.eState.

  u8 wrFlag;                /* True if writable */
  u8 atLast;                /* Cursor pointing to the last entry */
  u8 validNKey;             /* True if info.nKey is valid */
  u8 eState;                /* One of the CURSOR_XXX constants (see below) */
#ifndef SQLITE_OMIT_INCRBLOB
  u8 isIncrblobHandle;      /* True if this cursor is an incr. io handle */
#endif
  u8 hints;                             /* As configured by CursorSetHints() */
  i16 iPage;                            /* Index of current page in apPage */
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
};

/*
** Potential values for BtCursor.eState.

    */
    if( pSelect ){
      SelectDest dest;
      Table *pSelTab;

      assert(pParse->nTab==1);
      sqlite3VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
      sqlite3VdbeChangeP5(v, 1);
      pParse->nTab = 2;
      sqlite3SelectDestInit(&dest, SRT_Table, 1);
      sqlite3Select(pParse, pSelect, &dest);
      sqlite3VdbeAddOp1(v, OP_Close, 1);
      if( pParse->nErr==0 ){
        pSelTab = sqlite3ResultSetOfSelect(pParse, pSelect);
        if( pSelTab==0 ) return;
................................................................................
  }else{
    tnum = pIndex->tnum;
    sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
  }
  pKey = sqlite3IndexKeyinfo(pParse, pIndex);
  sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
                    (char *)pKey, P4_KEYINFO_HANDOFF);
  if( memRootPage>=0 ){
    sqlite3VdbeChangeP5(v, 1);
  }

#ifndef SQLITE_OMIT_MERGE_SORT
  /* Open the sorter cursor if we are to use one. */
  iSorter = pParse->nTab++;
  sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, 0, (char*)pKey, P4_KEYINFO);
#else
  iSorter = iTab;

    */
    if( pSelect ){
      SelectDest dest;
      Table *pSelTab;

      assert(pParse->nTab==1);
      sqlite3VdbeAddOp3(v, OP_OpenWrite, 1, pParse->regRoot, iDb);
      sqlite3VdbeChangeP5(v, OPFLAG_P2ISREG);
      pParse->nTab = 2;
      sqlite3SelectDestInit(&dest, SRT_Table, 1);
      sqlite3Select(pParse, pSelect, &dest);
      sqlite3VdbeAddOp1(v, OP_Close, 1);
      if( pParse->nErr==0 ){
        pSelTab = sqlite3ResultSetOfSelect(pParse, pSelect);
        if( pSelTab==0 ) return;
................................................................................
  }else{
    tnum = pIndex->tnum;
    sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
  }
  pKey = sqlite3IndexKeyinfo(pParse, pIndex);
  sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb, 
                    (char *)pKey, P4_KEYINFO_HANDOFF);

  sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR|((memRootPage>=0)?OPFLAG_P2ISREG:0));


#ifndef SQLITE_OMIT_MERGE_SORT
  /* Open the sorter cursor if we are to use one. */
  iSorter = pParse->nTab++;
  sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, 0, (char*)pKey, P4_KEYINFO);
#else
  iSorter = iTab;

        ** table allocated and opened above.
        */
        SelectDest dest;
        ExprList *pEList;

        assert( !isRowid );
        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
        dest.affinity = (u8)affinity;
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
        pExpr->x.pSelect->iLimit = 0;
        if( sqlite3Select(pParse, pExpr->x.pSelect, &dest) ){
          return 0;
        }
        pEList = pExpr->x.pSelect->pEList;
        if( ALWAYS(pEList!=0 && pEList->nExpr>0) ){ 
................................................................................
      assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );

      assert( ExprHasProperty(pExpr, EP_xIsSelect) );
      pSel = pExpr->x.pSelect;
      sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
      if( pExpr->op==TK_SELECT ){
        dest.eDest = SRT_Mem;
        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iParm);
        VdbeComment((v, "Init subquery result"));
      }else{
        dest.eDest = SRT_Exists;
        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iParm);
        VdbeComment((v, "Init EXISTS result"));
      }
      sqlite3ExprDelete(pParse->db, pSel->pLimit);
      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
                                  &sqlite3IntTokens[1]);
      pSel->iLimit = 0;
      if( sqlite3Select(pParse, pSel, &dest) ){
        return 0;
      }
      rReg = dest.iParm;
      ExprSetIrreducible(pExpr);
      break;
    }
  }

  if( testAddr>=0 ){
    sqlite3VdbeJumpHere(v, testAddr);

        ** table allocated and opened above.
        */
        SelectDest dest;
        ExprList *pEList;

        assert( !isRowid );
        sqlite3SelectDestInit(&dest, SRT_Set, pExpr->iTable);
        dest.affSdst = (u8)affinity;
        assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable );
        pExpr->x.pSelect->iLimit = 0;
        if( sqlite3Select(pParse, pExpr->x.pSelect, &dest) ){
          return 0;
        }
        pEList = pExpr->x.pSelect->pEList;
        if( ALWAYS(pEList!=0 && pEList->nExpr>0) ){ 
................................................................................
      assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT );

      assert( ExprHasProperty(pExpr, EP_xIsSelect) );
      pSel = pExpr->x.pSelect;
      sqlite3SelectDestInit(&dest, 0, ++pParse->nMem);
      if( pExpr->op==TK_SELECT ){
        dest.eDest = SRT_Mem;
        sqlite3VdbeAddOp2(v, OP_Null, 0, dest.iSDParm);
        VdbeComment((v, "Init subquery result"));
      }else{
        dest.eDest = SRT_Exists;
        sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iSDParm);
        VdbeComment((v, "Init EXISTS result"));
      }
      sqlite3ExprDelete(pParse->db, pSel->pLimit);
      pSel->pLimit = sqlite3PExpr(pParse, TK_INTEGER, 0, 0,
                                  &sqlite3IntTokens[1]);
      pSel->iLimit = 0;
      if( sqlite3Select(pParse, pSel, &dest) ){
        return 0;
      }
      rReg = dest.iSDParm;
      ExprSetIrreducible(pExpr);
      break;
    }
  }

  if( testAddr>=0 ){
    sqlite3VdbeJumpHere(v, testAddr);

    new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
  }
  if( new_size==pH->htsize ) return 0;
#endif

  /* The inability to allocates space for a larger hash table is
  ** a performance hit but it is not a fatal error.  So mark the
  ** allocation as a benign.




  */
  sqlite3BeginBenignMalloc();
  new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
  sqlite3EndBenignMalloc();

  if( new_ht==0 ) return 0;
  sqlite3_free(pH->ht);

    new_size = SQLITE_MALLOC_SOFT_LIMIT/sizeof(struct _ht);
  }
  if( new_size==pH->htsize ) return 0;
#endif

  /* The inability to allocates space for a larger hash table is
  ** a performance hit but it is not a fatal error.  So mark the
  ** allocation as a benign. Use sqlite3Malloc()/memset(0) instead of 
  ** sqlite3MallocZero() to make the allocation, as sqlite3MallocZero()
  ** only zeroes the requested number of bytes whereas this module will
  ** use the actual amount of space allocated for the hash table (which
  ** may be larger than the requested amount).
  */
  sqlite3BeginBenignMalloc();
  new_ht = (struct _ht *)sqlite3Malloc( new_size*sizeof(struct _ht) );
  sqlite3EndBenignMalloc();

  if( new_ht==0 ) return 0;
  sqlite3_free(pH->ht);

    int rc, j1;

    regEof = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof);      /* EOF <- 0 */
    VdbeComment((v, "SELECT eof flag"));
    sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
    addrSelect = sqlite3VdbeCurrentAddr(v)+2;
    sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iParm);
    j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
    VdbeComment((v, "Jump over SELECT coroutine"));

    /* Resolve the expressions in the SELECT statement and execute it. */
    rc = sqlite3Select(pParse, pSelect, &dest);
    assert( pParse->nErr==0 || rc );
    if( rc || NEVER(pParse->nErr) || db->mallocFailed ){
      goto insert_cleanup;
    }
    sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof);         /* EOF <- 1 */
    sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);   /* yield X */
    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
    VdbeComment((v, "End of SELECT coroutine"));
    sqlite3VdbeJumpHere(v, j1);                          /* label B: */

    regFromSelect = dest.iMem;
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;
    assert( dest.nMem==nColumn );

    /* Set useTempTable to TRUE if the result of the SELECT statement
    ** should be written into a temporary table (template 4).  Set to
    ** FALSE if each* row of the SELECT can be written directly into
    ** the destination table (template 3).
    **
    ** A temp table must be used if the table being updated is also one
................................................................................
      int addrTop;         /* Label "L" */
      int addrIf;          /* Address of jump to M */

      srcTab = pParse->nTab++;
      regRec = sqlite3GetTempReg(pParse);
      regTempRowid = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
      addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
      addrIf = sqlite3VdbeAddOp1(v, OP_If, regEof);
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
      sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid);
      sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
      sqlite3VdbeJumpHere(v, addrIf);
      sqlite3ReleaseTempReg(pParse, regRec);
................................................................................
    **
    **      C: yield X
    **         if EOF goto D
    **         insert the select result into <table> from R..R+n
    **         goto C
    **      D: ...
    */
    addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm);
    addrInsTop = sqlite3VdbeAddOp1(v, OP_If, regEof);
  }

  /* Allocate registers for holding the rowid of the new row,
  ** the content of the new row, and the assemblied row record.
  */
  regRowid = regIns = pParse->nMem+1;

    int rc, j1;

    regEof = ++pParse->nMem;
    sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof);      /* EOF <- 0 */
    VdbeComment((v, "SELECT eof flag"));
    sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem);
    addrSelect = sqlite3VdbeCurrentAddr(v)+2;
    sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iSDParm);
    j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
    VdbeComment((v, "Jump over SELECT coroutine"));

    /* Resolve the expressions in the SELECT statement and execute it. */
    rc = sqlite3Select(pParse, pSelect, &dest);
    assert( pParse->nErr==0 || rc );
    if( rc || NEVER(pParse->nErr) || db->mallocFailed ){
      goto insert_cleanup;
    }
    sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof);         /* EOF <- 1 */
    sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm);   /* yield X */
    sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort);
    VdbeComment((v, "End of SELECT coroutine"));
    sqlite3VdbeJumpHere(v, j1);                          /* label B: */

    regFromSelect = dest.iSdst;
    assert( pSelect->pEList );
    nColumn = pSelect->pEList->nExpr;
    assert( dest.nSdst==nColumn );

    /* Set useTempTable to TRUE if the result of the SELECT statement
    ** should be written into a temporary table (template 4).  Set to
    ** FALSE if each* row of the SELECT can be written directly into
    ** the destination table (template 3).
    **
    ** A temp table must be used if the table being updated is also one
................................................................................
      int addrTop;         /* Label "L" */
      int addrIf;          /* Address of jump to M */

      srcTab = pParse->nTab++;
      regRec = sqlite3GetTempReg(pParse);
      regTempRowid = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
      addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm);
      addrIf = sqlite3VdbeAddOp1(v, OP_If, regEof);
      sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
      sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid);
      sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid);
      sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
      sqlite3VdbeJumpHere(v, addrIf);
      sqlite3ReleaseTempReg(pParse, regRec);
................................................................................
    **
    **      C: yield X
    **         if EOF goto D
    **         insert the select result into <table> from R..R+n
    **         goto C
    **      D: ...
    */
    addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm);
    addrInsTop = sqlite3VdbeAddOp1(v, OP_If, regEof);
  }

  /* Allocate registers for holding the rowid of the new row,
  ** the content of the new row, and the assemblied row record.
  */
  regRowid = regIns = pParse->nMem+1;

#if defined(_WIN32_WCE)
# define SQLITE_OS_WINCE 1
#else
# define SQLITE_OS_WINCE 0
#endif

/*
** Determine if we are dealing with WindowsRT (Metro) as this has a different and
** incompatible API from win32.
*/
#if !defined(SQLITE_OS_WINRT)
# define SQLITE_OS_WINRT 0
#endif

/*
** When compiled for WinCE or WinRT, there is no concept of the current

#if defined(_WIN32_WCE)
# define SQLITE_OS_WINCE 1
#else
# define SQLITE_OS_WINCE 0
#endif

/*
** Determine if we are dealing with WinRT, which provides only a subset of
** the full Win32 API.
*/
#if !defined(SQLITE_OS_WINRT)
# define SQLITE_OS_WINRT 0
#endif

/*
** When compiled for WinCE or WinRT, there is no concept of the current

#else
  { "CreateFileW",             (SYSCALL)0,                       0 },
#endif

#define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
        LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)

#if !SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE)

  { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
#else
  { "CreateFileMappingW",      (SYSCALL)0,                       0 },
#endif

#define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
        DWORD,DWORD,DWORD,LPCWSTR))aSyscall[6].pCurrent)
................................................................................
#endif

#ifndef osLockFileEx
#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[45].pCurrent)
#endif

#if !SQLITE_OS_WINRT
  { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
#else
  { "MapViewOfFile",           (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        SIZE_T))aSyscall[46].pCurrent)
................................................................................
#else
  { "UnlockFileEx",            (SYSCALL)0,                       0 },
#endif

#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[55].pCurrent)


  { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },




#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[56].pCurrent)

  { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },

#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
        LPCSTR,LPBOOL))aSyscall[57].pCurrent)
................................................................................
#else
  { "WaitForSingleObject",     (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
        DWORD))aSyscall[60].pCurrent)

#if !SQLITE_OS_WINCE
  { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
#else
  { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
        BOOL))aSyscall[61].pCurrent)

#if !SQLITE_OS_WINCE
  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
#else
  { "SetFilePointerEx",        (SYSCALL)0,                       0 },
#endif

#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
        PLARGE_INTEGER,DWORD))aSyscall[62].pCurrent)
................................................................................
#else
  { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
#endif

#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[63].pCurrent)

#if SQLITE_OS_WINRT
  { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
#else
  { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
        SIZE_T))aSyscall[64].pCurrent)
................................................................................

#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[70].pCurrent)

  { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },

#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[71].pCurrent)

#if SQLITE_OS_WINRT
  { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
#else
  { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
#endif

#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[72].pCurrent)

#else
  { "CreateFileW",             (SYSCALL)0,                       0 },
#endif

#define osCreateFileW ((HANDLE(WINAPI*)(LPCWSTR,DWORD,DWORD, \
        LPSECURITY_ATTRIBUTES,DWORD,DWORD,HANDLE))aSyscall[5].pCurrent)

#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && defined(SQLITE_WIN32_HAS_WIDE) && \
        !defined(SQLITE_OMIT_WAL))
  { "CreateFileMappingW",      (SYSCALL)CreateFileMappingW,      0 },
#else
  { "CreateFileMappingW",      (SYSCALL)0,                       0 },
#endif

#define osCreateFileMappingW ((HANDLE(WINAPI*)(HANDLE,LPSECURITY_ATTRIBUTES, \
        DWORD,DWORD,DWORD,LPCWSTR))aSyscall[6].pCurrent)
................................................................................
#endif

#ifndef osLockFileEx
#define osLockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[45].pCurrent)
#endif

#if SQLITE_OS_WINCE || (!SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL))
  { "MapViewOfFile",           (SYSCALL)MapViewOfFile,           0 },
#else
  { "MapViewOfFile",           (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFile ((LPVOID(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        SIZE_T))aSyscall[46].pCurrent)
................................................................................
#else
  { "UnlockFileEx",            (SYSCALL)0,                       0 },
#endif

#define osUnlockFileEx ((BOOL(WINAPI*)(HANDLE,DWORD,DWORD,DWORD, \
        LPOVERLAPPED))aSyscall[55].pCurrent)

#if SQLITE_OS_WINCE || !defined(SQLITE_OMIT_WAL)
  { "UnmapViewOfFile",         (SYSCALL)UnmapViewOfFile,         0 },
#else
  { "UnmapViewOfFile",         (SYSCALL)0,                       0 },
#endif

#define osUnmapViewOfFile ((BOOL(WINAPI*)(LPCVOID))aSyscall[56].pCurrent)

  { "WideCharToMultiByte",     (SYSCALL)WideCharToMultiByte,     0 },

#define osWideCharToMultiByte ((int(WINAPI*)(UINT,DWORD,LPCWSTR,int,LPSTR,int, \
        LPCSTR,LPBOOL))aSyscall[57].pCurrent)
................................................................................
#else
  { "WaitForSingleObject",     (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObject ((DWORD(WINAPI*)(HANDLE, \
        DWORD))aSyscall[60].pCurrent)

#if SQLITE_OS_WINRT
  { "WaitForSingleObjectEx",   (SYSCALL)WaitForSingleObjectEx,   0 },
#else
  { "WaitForSingleObjectEx",   (SYSCALL)0,                       0 },
#endif

#define osWaitForSingleObjectEx ((DWORD(WINAPI*)(HANDLE,DWORD, \
        BOOL))aSyscall[61].pCurrent)

#if SQLITE_OS_WINRT
  { "SetFilePointerEx",        (SYSCALL)SetFilePointerEx,        0 },
#else
  { "SetFilePointerEx",        (SYSCALL)0,                       0 },
#endif

#define osSetFilePointerEx ((BOOL(WINAPI*)(HANDLE,LARGE_INTEGER, \
        PLARGE_INTEGER,DWORD))aSyscall[62].pCurrent)
................................................................................
#else
  { "GetFileInformationByHandleEx", (SYSCALL)0,                  0 },
#endif

#define osGetFileInformationByHandleEx ((BOOL(WINAPI*)(HANDLE, \
        FILE_INFO_BY_HANDLE_CLASS,LPVOID,DWORD))aSyscall[63].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
  { "MapViewOfFileFromApp",    (SYSCALL)MapViewOfFileFromApp,    0 },
#else
  { "MapViewOfFileFromApp",    (SYSCALL)0,                       0 },
#endif

#define osMapViewOfFileFromApp ((LPVOID(WINAPI*)(HANDLE,ULONG,ULONG64, \
        SIZE_T))aSyscall[64].pCurrent)
................................................................................

#define osOutputDebugStringW ((VOID(WINAPI*)(LPCWSTR))aSyscall[70].pCurrent)

  { "GetProcessHeap",          (SYSCALL)GetProcessHeap,          0 },

#define osGetProcessHeap ((HANDLE(WINAPI*)(VOID))aSyscall[71].pCurrent)

#if SQLITE_OS_WINRT && !defined(SQLITE_OMIT_WAL)
  { "CreateFileMappingFromApp", (SYSCALL)CreateFileMappingFromApp, 0 },
#else
  { "CreateFileMappingFromApp", (SYSCALL)0,                      0 },
#endif

#define osCreateFileMappingFromApp ((HANDLE(WINAPI*)(HANDLE, \
        LPSECURITY_ATTRIBUTES,ULONG,ULONG64,LPCWSTR))aSyscall[72].pCurrent)

  nNew = p->nHash*2;
  if( nNew<256 ){
    nNew = 256;
  }

  pcache1LeaveMutex(p->pGroup);
  if( p->nHash ){ sqlite3BeginBenignMalloc(); }
  apNew = (PgHdr1 **)sqlite3_malloc(sizeof(PgHdr1 *)*nNew);
  if( p->nHash ){ sqlite3EndBenignMalloc(); }
  pcache1EnterMutex(p->pGroup);
  if( apNew ){
    memset(apNew, 0, sizeof(PgHdr1 *)*nNew);
    for(i=0; i<p->nHash; i++){
      PgHdr1 *pPage;
      PgHdr1 *pNext = p->apHash[i];
      while( (pPage = pNext)!=0 ){
        unsigned int h = pPage->iKey % nNew;
        pNext = pPage->pNext;
        pPage->pNext = apNew[h];
................................................................................
  int separateCache = sqlite3GlobalConfig.bCoreMutex>0;
#endif

  assert( (szPage & (szPage-1))==0 && szPage>=512 && szPage<=65536 );
  assert( szExtra < 300 );

  sz = sizeof(PCache1) + sizeof(PGroup)*separateCache;
  pCache = (PCache1 *)sqlite3_malloc(sz);
  if( pCache ){
    memset(pCache, 0, sz);
    if( separateCache ){
      pGroup = (PGroup*)&pCache[1];
      pGroup->mxPinned = 10;
    }else{
      pGroup = &pcache1.grp;
    }
    pCache->pGroup = pGroup;

  nNew = p->nHash*2;
  if( nNew<256 ){
    nNew = 256;
  }

  pcache1LeaveMutex(p->pGroup);
  if( p->nHash ){ sqlite3BeginBenignMalloc(); }
  apNew = (PgHdr1 **)sqlite3MallocZero(sizeof(PgHdr1 *)*nNew);
  if( p->nHash ){ sqlite3EndBenignMalloc(); }
  pcache1EnterMutex(p->pGroup);
  if( apNew ){

    for(i=0; i<p->nHash; i++){
      PgHdr1 *pPage;
      PgHdr1 *pNext = p->apHash[i];
      while( (pPage = pNext)!=0 ){
        unsigned int h = pPage->iKey % nNew;
        pNext = pPage->pNext;
        pPage->pNext = apNew[h];
................................................................................
  int separateCache = sqlite3GlobalConfig.bCoreMutex>0;
#endif

  assert( (szPage & (szPage-1))==0 && szPage>=512 && szPage<=65536 );
  assert( szExtra < 300 );

  sz = sizeof(PCache1) + sizeof(PGroup)*separateCache;
  pCache = (PCache1 *)sqlite3MallocZero(sz);
  if( pCache ){

    if( separateCache ){
      pGroup = (PGroup*)&pCache[1];
      pGroup->mxPinned = 10;
    }else{
      pGroup = &pcache1.grp;
    }
    pCache->pGroup = pGroup;

}

/*
** Initialize a SelectDest structure.
*/
void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){
  pDest->eDest = (u8)eDest;
  pDest->iParm = iParm;
  pDest->affinity = 0;
  pDest->iMem = 0;
  pDest->nMem = 0;
}


/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/
................................................................................
  int iBreak              /* Jump here to break out of the inner loop */
){
  Vdbe *v = pParse->pVdbe;
  int i;
  int hasDistinct;        /* True if the DISTINCT keyword is present */
  int regResult;              /* Start of memory holding result set */
  int eDest = pDest->eDest;   /* How to dispose of results */
  int iParm = pDest->iParm;   /* First argument to disposal method */
  int nResultCol;             /* Number of result columns */

  assert( v );
  if( NEVER(v==0) ) return;
  assert( pEList!=0 );
  hasDistinct = distinct>=0;
  if( pOrderBy==0 && !hasDistinct ){
................................................................................
  /* Pull the requested columns.
  */
  if( nColumn>0 ){
    nResultCol = nColumn;
  }else{
    nResultCol = pEList->nExpr;
  }
  if( pDest->iMem==0 ){
    pDest->iMem = pParse->nMem+1;
    pDest->nMem = nResultCol;
    pParse->nMem += nResultCol;
  }else{ 
    assert( pDest->nMem==nResultCol );
  }
  regResult = pDest->iMem;
  if( nColumn>0 ){
    for(i=0; i<nColumn; i++){
      sqlite3VdbeAddOp3(v, OP_Column, srcTab, i, regResult+i);
    }
  }else if( eDest!=SRT_Exists ){
    /* If the destination is an EXISTS(...) expression, the actual
    ** values returned by the SELECT are not required.
................................................................................
#ifndef SQLITE_OMIT_SUBQUERY
    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      assert( nColumn==1 );
      p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affinity);
      if( pOrderBy ){
        /* At first glance you would think we could optimize out the
        ** ORDER BY in this case since the order of entries in the set
        ** does not matter.  But there might be a LIMIT clause, in which
        ** case the order does matter */
        pushOntoSorter(pParse, pOrderBy, p, regResult);
      }else{
................................................................................
      testcase( eDest==SRT_Output );
      if( pOrderBy ){
        int r1 = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
        pushOntoSorter(pParse, pOrderBy, p, r1);
        sqlite3ReleaseTempReg(pParse, r1);
      }else if( eDest==SRT_Coroutine ){
        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
      }else{
        sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
        sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
      }
      break;
    }

................................................................................
  int addrContinue = sqlite3VdbeMakeLabel(v);  /* Jump here for next cycle */
  int addr;
  int iTab;
  int pseudoTab = 0;
  ExprList *pOrderBy = p->pOrderBy;

  int eDest = pDest->eDest;
  int iParm = pDest->iParm;

  int regRow;
  int regRowid;

  iTab = pOrderBy->iECursor;
  regRow = sqlite3GetTempReg(pParse);
  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
................................................................................
#endif
    default: {
      int i;
      assert( eDest==SRT_Output || eDest==SRT_Coroutine ); 
      testcase( eDest==SRT_Output );
      testcase( eDest==SRT_Coroutine );
      for(i=0; i<nColumn; i++){
        assert( regRow!=pDest->iMem+i );
        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iMem+i);
        if( i==0 ){
          sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
        }
      }
      if( eDest==SRT_Output ){
        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iMem, nColumn);
        sqlite3ExprCacheAffinityChange(pParse, pDest->iMem, nColumn);
      }else{
        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
      }
      break;
    }
  }
  sqlite3ReleaseTempReg(pParse, regRow);
  sqlite3ReleaseTempReg(pParse, regRowid);

................................................................................
  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );  /* The VDBE already created by calling function */

  /* Create the destination temporary table if necessary
  */
  if( dest.eDest==SRT_EphemTab ){
    assert( p->pEList );
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iParm, p->pEList->nExpr);
    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
    dest.eDest = SRT_Table;
  }

  /* Make sure all SELECTs in the statement have the same number of elements
  ** in their result sets.
  */
................................................................................
        /* We can reuse a temporary table generated by a SELECT to our
        ** right.
        */
        assert( p->pRightmost!=p );  /* Can only happen for leftward elements
                                     ** of a 3-way or more compound */
        assert( p->pLimit==0 );      /* Not allowed on leftward elements */
        assert( p->pOffset==0 );     /* Not allowed on leftward elements */
        unionTab = dest.iParm;
      }else{
        /* We will need to create our own temporary table to hold the
        ** intermediate results.
        */
        unionTab = pParse->nTab++;
        assert( p->pOrderBy==0 );
        addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, unionTab, 0);
................................................................................
      p->pOffset = pOffset;
      p->iLimit = 0;
      p->iOffset = 0;

      /* Convert the data in the temporary table into whatever form
      ** it is that we currently need.
      */
      assert( unionTab==dest.iParm || dest.eDest!=priorOp );
      if( dest.eDest!=priorOp ){
        int iCont, iBreak, iStart;
        assert( p->pEList );
        if( dest.eDest==SRT_Output ){
          Select *pFirst = p;
          while( pFirst->pPrior ) pFirst = pFirst->pPrior;
          generateColumnNames(pParse, 0, pFirst->pEList);
................................................................................
      assert( p->addrOpenEphm[1] == -1 );
      p->addrOpenEphm[1] = addr;
      p->pPrior = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      intersectdest.iParm = tab2;
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &intersectdest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
      if( p->nSelectRow>pPrior->nSelectRow ) p->nSelectRow = pPrior->nSelectRow;
      sqlite3ExprDelete(db, p->pLimit);
................................................................................
        pLoop->addrOpenEphm[i] = -1;
      }
    }
    sqlite3DbFree(db, pKeyInfo);
  }

multi_select_end:
  pDest->iMem = dest.iMem;
  pDest->nMem = dest.nMem;
  sqlite3SelectDelete(db, pDelete);
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

/*
** Code an output subroutine for a coroutine implementation of a
** SELECT statment.
**
** The data to be output is contained in pIn->iMem.  There are
** pIn->nMem columns to be output.  pDest is where the output should
** be sent.
**
** regReturn is the number of the register holding the subroutine
** return address.
**
** If regPrev>0 then it is the first register in a vector that
** records the previous output.  mem[regPrev] is a flag that is false
................................................................................
  iContinue = sqlite3VdbeMakeLabel(v);

  /* Suppress duplicates for UNION, EXCEPT, and INTERSECT 
  */
  if( regPrev ){
    int j1, j2;
    j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev);
    j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iMem, regPrev+1, pIn->nMem,
                              (char*)pKeyInfo, p4type);
    sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3ExprCodeCopy(pParse, pIn->iMem, regPrev+1, pIn->nMem);
    sqlite3VdbeAddOp2(v, OP_Integer, 1, regPrev);
  }
  if( pParse->db->mallocFailed ) return 0;

  /* Suppress the the first OFFSET entries if there is an OFFSET clause
  */
  codeOffset(v, p, iContinue);
................................................................................
    */
    case SRT_Table:
    case SRT_EphemTab: {
      int r1 = sqlite3GetTempReg(pParse);
      int r2 = sqlite3GetTempReg(pParse);
      testcase( pDest->eDest==SRT_Table );
      testcase( pDest->eDest==SRT_EphemTab );
      sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iMem, pIn->nMem, r1);
      sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iParm, r2);
      sqlite3VdbeAddOp3(v, OP_Insert, pDest->iParm, r1, r2);
      sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
      sqlite3ReleaseTempReg(pParse, r2);
      sqlite3ReleaseTempReg(pParse, r1);
      break;
    }

#ifndef SQLITE_OMIT_SUBQUERY
    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      int r1;
      assert( pIn->nMem==1 );
      p->affinity = 
         sqlite3CompareAffinity(p->pEList->a[0].pExpr, pDest->affinity);
      r1 = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iMem, 1, r1, &p->affinity, 1);
      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, 1);
      sqlite3VdbeAddOp2(v, OP_IdxInsert, pDest->iParm, r1);
      sqlite3ReleaseTempReg(pParse, r1);
      break;
    }

#if 0  /* Never occurs on an ORDER BY query */
    /* If any row exist in the result set, record that fact and abort.
    */
    case SRT_Exists: {
      sqlite3VdbeAddOp2(v, OP_Integer, 1, pDest->iParm);
      /* The LIMIT clause will terminate the loop for us */
      break;
    }
#endif

    /* If this is a scalar select that is part of an expression, then
    ** store the results in the appropriate memory cell and break out
    ** of the scan loop.
    */
    case SRT_Mem: {
      assert( pIn->nMem==1 );
      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iParm, 1);
      /* The LIMIT clause will jump out of the loop for us */
      break;
    }
#endif /* #ifndef SQLITE_OMIT_SUBQUERY */

    /* The results are stored in a sequence of registers
    ** starting at pDest->iMem.  Then the co-routine yields.
    */
    case SRT_Coroutine: {
      if( pDest->iMem==0 ){
        pDest->iMem = sqlite3GetTempRange(pParse, pIn->nMem);
        pDest->nMem = pIn->nMem;
      }
      sqlite3ExprCodeMove(pParse, pIn->iMem, pDest->iMem, pDest->nMem);
      sqlite3VdbeAddOp1(v, OP_Yield, pDest->iParm);
      break;
    }

    /* If none of the above, then the result destination must be
    ** SRT_Output.  This routine is never called with any other
    ** destination other than the ones handled above or SRT_Output.
    **
    ** For SRT_Output, results are stored in a sequence of registers.  
    ** Then the OP_ResultRow opcode is used to cause sqlite3_step() to
    ** return the next row of result.
    */
    default: {
      assert( pDest->eDest==SRT_Output );
      sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iMem, pIn->nMem);
      sqlite3ExprCacheAffinityChange(pParse, pIn->iMem, pIn->nMem);
      break;
    }
  }

  /* Jump to the end of the loop if the LIMIT is reached.
  */
  if( p->iLimit ){
................................................................................
  sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
  sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);

  /* Implement the main merge loop
  */
  sqlite3VdbeResolveLabel(v, labelCmpr);
  sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
  sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, nOrderBy,
                         (char*)pKeyMerge, P4_KEYINFO_HANDOFF);
  sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);

  /* Release temporary registers
  */
  if( regPrev ){
    sqlite3ReleaseTempRange(pParse, regPrev, nOrderBy+1);
................................................................................
**     pDest->eDest    Result
**     ------------    -------------------------------------------
**     SRT_Output      Generate a row of output (using the OP_ResultRow
**                     opcode) for each row in the result set.
**
**     SRT_Mem         Only valid if the result is a single column.
**                     Store the first column of the first result row
**                     in register pDest->iParm then abandon the rest
**                     of the query.  This destination implies "LIMIT 1".
**
**     SRT_Set         The result must be a single column.  Store each
**                     row of result as the key in table pDest->iParm. 
**                     Apply the affinity pDest->affinity before storing
**                     results.  Used to implement "IN (SELECT ...)".
**
**     SRT_Union       Store results as a key in a temporary table pDest->iParm.

**
**     SRT_Except      Remove results from the temporary table pDest->iParm.
**
**     SRT_Table       Store results in temporary table pDest->iParm.
**                     This is like SRT_EphemTab except that the table
**                     is assumed to already be open.
**
**     SRT_EphemTab    Create an temporary table pDest->iParm and store
**                     the result there. The cursor is left open after
**                     returning.  This is like SRT_Table except that
**                     this destination uses OP_OpenEphemeral to create
**                     the table first.
**
**     SRT_Coroutine   Generate a co-routine that returns a new row of
**                     results each time it is invoked.  The entry point
**                     of the co-routine is stored in register pDest->iParm.
**
**     SRT_Exists      Store a 1 in memory cell pDest->iParm if the result
**                     set is not empty.
**
**     SRT_Discard     Throw the results away.  This is used by SELECT
**                     statements within triggers whose only purpose is
**                     the side-effects of functions.
**
** This routine returns the number of errors.  If any errors are
................................................................................
  }else{
    addrSortIndex = -1;
  }

  /* If the output is destined for a temporary table, open that table.
  */
  if( pDest->eDest==SRT_EphemTab ){
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iParm, pEList->nExpr);
  }

  /* Set the limiter.
  */
  iEnd = sqlite3VdbeMakeLabel(v);
  p->nSelectRow = (double)LARGEST_INT64;
  computeLimitRegisters(pParse, p, iEnd);

}

/*
** Initialize a SelectDest structure.
*/
void sqlite3SelectDestInit(SelectDest *pDest, int eDest, int iParm){
  pDest->eDest = (u8)eDest;
  pDest->iSDParm = iParm;
  pDest->affSdst = 0;
  pDest->iSdst = 0;
  pDest->nSdst = 0;
}


/*
** Allocate a new Select structure and return a pointer to that
** structure.
*/
................................................................................
  int iBreak              /* Jump here to break out of the inner loop */
){
  Vdbe *v = pParse->pVdbe;
  int i;
  int hasDistinct;        /* True if the DISTINCT keyword is present */
  int regResult;              /* Start of memory holding result set */
  int eDest = pDest->eDest;   /* How to dispose of results */
  int iParm = pDest->iSDParm; /* First argument to disposal method */
  int nResultCol;             /* Number of result columns */

  assert( v );
  if( NEVER(v==0) ) return;
  assert( pEList!=0 );
  hasDistinct = distinct>=0;
  if( pOrderBy==0 && !hasDistinct ){
................................................................................
  /* Pull the requested columns.
  */
  if( nColumn>0 ){
    nResultCol = nColumn;
  }else{
    nResultCol = pEList->nExpr;
  }
  if( pDest->iSdst==0 ){
    pDest->iSdst = pParse->nMem+1;
    pDest->nSdst = nResultCol;
    pParse->nMem += nResultCol;
  }else{ 
    assert( pDest->nSdst==nResultCol );
  }
  regResult = pDest->iSdst;
  if( nColumn>0 ){
    for(i=0; i<nColumn; i++){
      sqlite3VdbeAddOp3(v, OP_Column, srcTab, i, regResult+i);
    }
  }else if( eDest!=SRT_Exists ){
    /* If the destination is an EXISTS(...) expression, the actual
    ** values returned by the SELECT are not required.
................................................................................
#ifndef SQLITE_OMIT_SUBQUERY
    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      assert( nColumn==1 );
      p->affinity = sqlite3CompareAffinity(pEList->a[0].pExpr, pDest->affSdst);
      if( pOrderBy ){
        /* At first glance you would think we could optimize out the
        ** ORDER BY in this case since the order of entries in the set
        ** does not matter.  But there might be a LIMIT clause, in which
        ** case the order does matter */
        pushOntoSorter(pParse, pOrderBy, p, regResult);
      }else{
................................................................................
      testcase( eDest==SRT_Output );
      if( pOrderBy ){
        int r1 = sqlite3GetTempReg(pParse);
        sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nColumn, r1);
        pushOntoSorter(pParse, pOrderBy, p, r1);
        sqlite3ReleaseTempReg(pParse, r1);
      }else if( eDest==SRT_Coroutine ){
        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
      }else{
        sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nColumn);
        sqlite3ExprCacheAffinityChange(pParse, regResult, nColumn);
      }
      break;
    }

................................................................................
  int addrContinue = sqlite3VdbeMakeLabel(v);  /* Jump here for next cycle */
  int addr;
  int iTab;
  int pseudoTab = 0;
  ExprList *pOrderBy = p->pOrderBy;

  int eDest = pDest->eDest;
  int iParm = pDest->iSDParm;

  int regRow;
  int regRowid;

  iTab = pOrderBy->iECursor;
  regRow = sqlite3GetTempReg(pParse);
  if( eDest==SRT_Output || eDest==SRT_Coroutine ){
................................................................................
#endif
    default: {
      int i;
      assert( eDest==SRT_Output || eDest==SRT_Coroutine ); 
      testcase( eDest==SRT_Output );
      testcase( eDest==SRT_Coroutine );
      for(i=0; i<nColumn; i++){
        assert( regRow!=pDest->iSdst+i );
        sqlite3VdbeAddOp3(v, OP_Column, pseudoTab, i, pDest->iSdst+i);
        if( i==0 ){
          sqlite3VdbeChangeP5(v, OPFLAG_CLEARCACHE);
        }
      }
      if( eDest==SRT_Output ){
        sqlite3VdbeAddOp2(v, OP_ResultRow, pDest->iSdst, nColumn);
        sqlite3ExprCacheAffinityChange(pParse, pDest->iSdst, nColumn);
      }else{
        sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
      }
      break;
    }
  }
  sqlite3ReleaseTempReg(pParse, regRow);
  sqlite3ReleaseTempReg(pParse, regRowid);

................................................................................
  v = sqlite3GetVdbe(pParse);
  assert( v!=0 );  /* The VDBE already created by calling function */

  /* Create the destination temporary table if necessary
  */
  if( dest.eDest==SRT_EphemTab ){
    assert( p->pEList );
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, dest.iSDParm, p->pEList->nExpr);
    sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
    dest.eDest = SRT_Table;
  }

  /* Make sure all SELECTs in the statement have the same number of elements
  ** in their result sets.
  */
................................................................................
        /* We can reuse a temporary table generated by a SELECT to our
        ** right.
        */
        assert( p->pRightmost!=p );  /* Can only happen for leftward elements
                                     ** of a 3-way or more compound */
        assert( p->pLimit==0 );      /* Not allowed on leftward elements */
        assert( p->pOffset==0 );     /* Not allowed on leftward elements */
        unionTab = dest.iSDParm;
      }else{
        /* We will need to create our own temporary table to hold the
        ** intermediate results.
        */
        unionTab = pParse->nTab++;
        assert( p->pOrderBy==0 );
        addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, unionTab, 0);
................................................................................
      p->pOffset = pOffset;
      p->iLimit = 0;
      p->iOffset = 0;

      /* Convert the data in the temporary table into whatever form
      ** it is that we currently need.
      */
      assert( unionTab==dest.iSDParm || dest.eDest!=priorOp );
      if( dest.eDest!=priorOp ){
        int iCont, iBreak, iStart;
        assert( p->pEList );
        if( dest.eDest==SRT_Output ){
          Select *pFirst = p;
          while( pFirst->pPrior ) pFirst = pFirst->pPrior;
          generateColumnNames(pParse, 0, pFirst->pEList);
................................................................................
      assert( p->addrOpenEphm[1] == -1 );
      p->addrOpenEphm[1] = addr;
      p->pPrior = 0;
      pLimit = p->pLimit;
      p->pLimit = 0;
      pOffset = p->pOffset;
      p->pOffset = 0;
      intersectdest.iSDParm = tab2;
      explainSetInteger(iSub2, pParse->iNextSelectId);
      rc = sqlite3Select(pParse, p, &intersectdest);
      testcase( rc!=SQLITE_OK );
      pDelete = p->pPrior;
      p->pPrior = pPrior;
      if( p->nSelectRow>pPrior->nSelectRow ) p->nSelectRow = pPrior->nSelectRow;
      sqlite3ExprDelete(db, p->pLimit);
................................................................................
        pLoop->addrOpenEphm[i] = -1;
      }
    }
    sqlite3DbFree(db, pKeyInfo);
  }

multi_select_end:
  pDest->iSdst = dest.iSdst;
  pDest->nSdst = dest.nSdst;
  sqlite3SelectDelete(db, pDelete);
  return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */

/*
** Code an output subroutine for a coroutine implementation of a
** SELECT statment.
**
** The data to be output is contained in pIn->iSdst.  There are
** pIn->nSdst columns to be output.  pDest is where the output should
** be sent.
**
** regReturn is the number of the register holding the subroutine
** return address.
**
** If regPrev>0 then it is the first register in a vector that
** records the previous output.  mem[regPrev] is a flag that is false
................................................................................
  iContinue = sqlite3VdbeMakeLabel(v);

  /* Suppress duplicates for UNION, EXCEPT, and INTERSECT 
  */
  if( regPrev ){
    int j1, j2;
    j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev);
    j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iSdst, regPrev+1, pIn->nSdst,
                              (char*)pKeyInfo, p4type);
    sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2);
    sqlite3VdbeJumpHere(v, j1);
    sqlite3ExprCodeCopy(pParse, pIn->iSdst, regPrev+1, pIn->nSdst);
    sqlite3VdbeAddOp2(v, OP_Integer, 1, regPrev);
  }
  if( pParse->db->mallocFailed ) return 0;

  /* Suppress the the first OFFSET entries if there is an OFFSET clause
  */
  codeOffset(v, p, iContinue);
................................................................................
    */
    case SRT_Table:
    case SRT_EphemTab: {
      int r1 = sqlite3GetTempReg(pParse);
      int r2 = sqlite3GetTempReg(pParse);
      testcase( pDest->eDest==SRT_Table );
      testcase( pDest->eDest==SRT_EphemTab );
      sqlite3VdbeAddOp3(v, OP_MakeRecord, pIn->iSdst, pIn->nSdst, r1);
      sqlite3VdbeAddOp2(v, OP_NewRowid, pDest->iSDParm, r2);
      sqlite3VdbeAddOp3(v, OP_Insert, pDest->iSDParm, r1, r2);
      sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
      sqlite3ReleaseTempReg(pParse, r2);
      sqlite3ReleaseTempReg(pParse, r1);
      break;
    }

#ifndef SQLITE_OMIT_SUBQUERY
    /* If we are creating a set for an "expr IN (SELECT ...)" construct,
    ** then there should be a single item on the stack.  Write this
    ** item into the set table with bogus data.
    */
    case SRT_Set: {
      int r1;
      assert( pIn->nSdst==1 );
      p->affinity = 
         sqlite3CompareAffinity(p->pEList->a[0].pExpr, pDest->affSdst);
      r1 = sqlite3GetTempReg(pParse);
      sqlite3VdbeAddOp4(v, OP_MakeRecord, pIn->iSdst, 1, r1, &p->affinity, 1);
      sqlite3ExprCacheAffinityChange(pParse, pIn->iSdst, 1);
      sqlite3VdbeAddOp2(v, OP_IdxInsert, pDest->iSDParm, r1);
      sqlite3ReleaseTempReg(pParse, r1);
      break;
    }

#if 0  /* Never occurs on an ORDER BY query */
    /* If any row exist in the result set, record that fact and abort.
    */
    case SRT_Exists: {
      sqlite3VdbeAddOp2(v, OP_Integer, 1, pDest->iSDParm);
      /* The LIMIT clause will terminate the loop for us */
      break;
    }
#endif

    /* If this is a scalar select that is part of an expression, then
    ** store the results in the appropriate memory cell and break out
    ** of the scan loop.
    */
    case SRT_Mem: {
      assert( pIn->nSdst==1 );
      sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSDParm, 1);
      /* The LIMIT clause will jump out of the loop for us */
      break;
    }
#endif /* #ifndef SQLITE_OMIT_SUBQUERY */

    /* The results are stored in a sequence of registers
    ** starting at pDest->iSdst.  Then the co-routine yields.
    */
    case SRT_Coroutine: {
      if( pDest->iSdst==0 ){
        pDest->iSdst = sqlite3GetTempRange(pParse, pIn->nSdst);
        pDest->nSdst = pIn->nSdst;
      }
      sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSdst, pDest->nSdst);
      sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
      break;
    }

    /* If none of the above, then the result destination must be
    ** SRT_Output.  This routine is never called with any other
    ** destination other than the ones handled above or SRT_Output.
    **
    ** For SRT_Output, results are stored in a sequence of registers.  
    ** Then the OP_ResultRow opcode is used to cause sqlite3_step() to
    ** return the next row of result.
    */
    default: {
      assert( pDest->eDest==SRT_Output );
      sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iSdst, pIn->nSdst);
      sqlite3ExprCacheAffinityChange(pParse, pIn->iSdst, pIn->nSdst);
      break;
    }
  }

  /* Jump to the end of the loop if the LIMIT is reached.
  */
  if( p->iLimit ){
................................................................................
  sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
  sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);

  /* Implement the main merge loop
  */
  sqlite3VdbeResolveLabel(v, labelCmpr);
  sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
  sqlite3VdbeAddOp4(v, OP_Compare, destA.iSdst, destB.iSdst, nOrderBy,
                         (char*)pKeyMerge, P4_KEYINFO_HANDOFF);
  sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);

  /* Release temporary registers
  */
  if( regPrev ){
    sqlite3ReleaseTempRange(pParse, regPrev, nOrderBy+1);
................................................................................
**     pDest->eDest    Result
**     ------------    -------------------------------------------
**     SRT_Output      Generate a row of output (using the OP_ResultRow
**                     opcode) for each row in the result set.
**
**     SRT_Mem         Only valid if the result is a single column.
**                     Store the first column of the first result row
**                     in register pDest->iSDParm then abandon the rest
**                     of the query.  This destination implies "LIMIT 1".
**
**     SRT_Set         The result must be a single column.  Store each
**                     row of result as the key in table pDest->iSDParm. 
**                     Apply the affinity pDest->affSdst before storing
**                     results.  Used to implement "IN (SELECT ...)".
**
**     SRT_Union       Store results as a key in a temporary table 
**                     identified by pDest->iSDParm.
**
**     SRT_Except      Remove results from the temporary table pDest->iSDParm.
**
**     SRT_Table       Store results in temporary table pDest->iSDParm.
**                     This is like SRT_EphemTab except that the table
**                     is assumed to already be open.
**
**     SRT_EphemTab    Create an temporary table pDest->iSDParm and store
**                     the result there. The cursor is left open after
**                     returning.  This is like SRT_Table except that
**                     this destination uses OP_OpenEphemeral to create
**                     the table first.
**
**     SRT_Coroutine   Generate a co-routine that returns a new row of
**                     results each time it is invoked.  The entry point
**                     of the co-routine is stored in register pDest->iSDParm.
**
**     SRT_Exists      Store a 1 in memory cell pDest->iSDParm if the result
**                     set is not empty.
**
**     SRT_Discard     Throw the results away.  This is used by SELECT
**                     statements within triggers whose only purpose is
**                     the side-effects of functions.
**
** This routine returns the number of errors.  If any errors are
................................................................................
  }else{
    addrSortIndex = -1;
  }

  /* If the output is destined for a temporary table, open that table.
  */
  if( pDest->eDest==SRT_EphemTab ){
    sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pDest->iSDParm, pEList->nExpr);
  }

  /* Set the limiter.
  */
  iEnd = sqlite3VdbeMakeLabel(v);
  p->nSelectRow = (double)LARGEST_INT64;
  computeLimitRegisters(pParse, p, iEnd);

** they return.  Hence, the calling function can deallocate or
** modify the text after they return without harm.
** ^The sqlite3_result_error_code() function changes the error code
** returned by SQLite as a result of an error in a function.  ^By default,
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
**
** ^The sqlite3_result_toobig() interface causes SQLite to throw an error
** indicating that a string or BLOB is too long to represent.
**
** ^The sqlite3_result_nomem() interface causes SQLite to throw an error
** indicating that a memory allocation failed.
**
** ^The sqlite3_result_int() interface sets the return value
** of the application-defined function to be the 32-bit signed integer
** value given in the 2nd argument.
** ^The sqlite3_result_int64() interface sets the return value
** of the application-defined function to be the 64-bit signed integer
** value given in the 2nd argument.

** they return.  Hence, the calling function can deallocate or
** modify the text after they return without harm.
** ^The sqlite3_result_error_code() function changes the error code
** returned by SQLite as a result of an error in a function.  ^By default,
** the error code is SQLITE_ERROR.  ^A subsequent call to sqlite3_result_error()
** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.
**
** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an
** error indicating that a string or BLOB is too long to represent.
**
** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an
** error indicating that a memory allocation failed.
**
** ^The sqlite3_result_int() interface sets the return value
** of the application-defined function to be the 32-bit signed integer
** value given in the 2nd argument.
** ^The sqlite3_result_int64() interface sets the return value
** of the application-defined function to be the 64-bit signed integer
** value given in the 2nd argument.

/*
** A structure used to customize the behavior of sqlite3Select(). See
** comments above sqlite3Select() for details.
*/
typedef struct SelectDest SelectDest;
struct SelectDest {
  u8 eDest;         /* How to dispose of the results */
  u8 affinity;      /* Affinity used when eDest==SRT_Set */
  int iParm;        /* A parameter used by the eDest disposal method */
  int iMem;         /* Base register where results are written */
  int nMem;         /* Number of registers allocated */
};

/*
** During code generation of statements that do inserts into AUTOINCREMENT 
** tables, the following information is attached to the Table.u.autoInc.p
** pointer of each autoincrement table to record some side information that
** the code generator needs.  We have to keep per-table autoincrement
................................................................................
#define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
#define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */



/*
 * Each trigger present in the database schema is stored as an instance of
 * struct Trigger. 
 *
 * Pointers to instances of struct Trigger are stored in two ways.
 * 1. In the "trigHash" hash table (part of the sqlite3* that represents the 

/*
** A structure used to customize the behavior of sqlite3Select(). See
** comments above sqlite3Select() for details.
*/
typedef struct SelectDest SelectDest;
struct SelectDest {
  u8 eDest;         /* How to dispose of the results */
  u8 affSdst;       /* Affinity used when eDest==SRT_Set */
  int iSDParm;      /* A parameter used by the eDest disposal method */
  int iSdst;        /* Base register where results are written */
  int nSdst;        /* Number of registers allocated */
};

/*
** During code generation of statements that do inserts into AUTOINCREMENT 
** tables, the following information is attached to the Table.u.autoInc.p
** pointer of each autoincrement table to record some side information that
** the code generator needs.  We have to keep per-table autoincrement
................................................................................
#define OPFLAG_LASTROWID     0x02    /* Set to update db->lastRowid */
#define OPFLAG_ISUPDATE      0x04    /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND        0x08    /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10    /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_CLEARCACHE    0x20    /* Clear pseudo-table cache in OP_Column */
#define OPFLAG_LENGTHARG     0x40    /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG     0x80    /* OP_Column only used for typeof() */
#define OPFLAG_BULKCSR       0x01    /* OP_Open** used to open bulk cursor */
#define OPFLAG_P2ISREG       0x02    /* P2 to OP_Open** is a register number */

/*
 * Each trigger present in the database schema is stored as an instance of
 * struct Trigger. 
 *
 * Pointers to instances of struct Trigger are stored in two ways.
 * 1. In the "trigHash" hash table (part of the sqlite3* that represents the 

**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This module implements a VIRTUAL TABLE that can be used to search
** a large vocabulary for close matches.  For example, this virtual
** table can be used to suggest corrections to misspelled words.  Or,
** it could be used with FTS4 to do full-text search using potentially
** misspelled words.
**
** Create an instance of the virtual table this way:
**
**    CREATE VIRTUAL TABLE demo USING spellfix1;
**
** The "spellfix1" term is the name of this module.  The "demo" is the
** name of the virtual table you will be creating.  The table is initially
** empty.  You have to populate it with your vocabulary.  Suppose you
** have a list of words in a table named "big_vocabulary".  Then do this:
**
**    INSERT INTO demo(word) SELECT word FROM big_vocabulary;
**
** If you intend to use this virtual table in cooperation with an FTS4
** table (for spelling correctly of search terms) then you can extract
** the vocabulary using an fts3aux table:
**
**    INSERT INTO demo(word) SELECT term FROM search_aux WHERE col='*';
**
** You can also provide the virtual table with a "rank" for each word.
** The "rank" is an estimate of how common the word is.  Larger numbers
** mean the word is more common.  If you omit the rank when populating
** the table, then a rank of 1 is assumed.  But if you have rank 
** information, you can supply it and the virtual table will show a
** slight preference for selecting more commonly used terms.  To
** populate the rank from an fts4aux table "search_aux" do something
** like this:
**
**    INSERT INTO demo(word,rank)
**        SELECT term, documents FROM search_aux WHERE col='*';
**
** To query the virtual table, include a MATCH operator in the WHERE
** clause.  For example:
**
**    SELECT word FROM demo WHERE word MATCH 'kennasaw';
**
** Using a dataset of American place names (derived from
** http://geonames.usgs.gov/domestic/download_data.htm) the query above
** returns 20 results beginning with:
**
**    kennesaw
**    kenosha
**    kenesaw
**    kenaga
**    keanak
**
** If you append the character '*' to the end of the pattern, then
** a prefix search is performed.  For example:
**
**    SELECT word FROM demo WHERE word MATCH 'kennes*';
**
** Yields 20 results beginning with:
**
**    kennesaw
**    kennestone
**    kenneson
**    kenneys
**    keanes
**    keenes
**
** The virtual table actually has a unique rowid with five columns plus three
** extra hidden columns.  The columns are as follows:
**
**    rowid         A unique integer number associated with each
**                  vocabulary item in the table.  This can be used
**                  as a foreign key on other tables in the database.
**
**    word          The text of the word that matches the pattern.
**                  Both word and pattern can contains unicode characters
**                  and can be mixed case.
**
**    rank          This is the rank of the word, as specified in the
**                  original INSERT statement.
**
**    distance      This is an edit distance or Levensthein distance going
**                  from the pattern to the word.
**
**    langid        This is the language-id of the word.  All queries are
**                  against a single language-id, which defaults to 0.
**                  For any given query this value is the same on all rows.
**
**    score         The score is a combination of rank and distance.  The
**                  idea is that a lower score is better.  The virtual table
**                  attempts to find words with the lowest score and 
**                  by default (unless overridden by ORDER BY) returns
**                  results in order of increasing score.
**
**    matchlen      For prefix queries, the number of characters in the prefix
**                  of the returned value (word) that matched the query term.
**                  For non-prefix queries, the number of characters in the 
**                  returned value.
**
**    top           (HIDDEN)  For any query, this value is the same on all
**                  rows.  It is an integer which is the maximum number of
**                  rows that will be output.  The actually number of rows
**                  output might be less than this number, but it will never
**                  be greater.  The default value for top is 20, but that
**                  can be changed for each query by including a term of
**                  the form "top=N" in the WHERE clause of the query.
**
**    scope         (HIDDEN)  For any query, this value is the same on all
**                  rows.  The scope is a measure of how widely the virtual
**                  table looks for matching words.  Smaller values of
**                  scope cause a broader search.  The scope is normally
**                  choosen automatically and is capped at 4.  Applications
**                  can change the scope by including a term of the form
**                  "scope=N" in the WHERE clause of the query.  Increasing
**                  the scope will make the query run faster, but will reduce
**                  the possible corrections.
**
**    srchcnt       (HIDDEN)  For any query, this value is the same on all
**                  rows.  This value is an integer which is the number of
**                  of words examined using the edit-distance algorithm to
**                  find the top matches that are ultimately displayed.  This
**                  value is for diagnostic use only.
**
**    soundslike    (HIDDEN)  When inserting vocabulary entries, this field
**                  can be set to an spelling that matches what the word
**                  sounds like.  See the DEALING WITH UNUSUAL AND DIFFICULT
**                  SPELLINGS section below for details.
**
** When inserting into or updating the virtual table, only the rowid, word,
** rank, and langid may be changes.  Any attempt to set or modify the values
** of distance, score, top, scope, or srchcnt is silently ignored.
**
** ALGORITHM
**
** A shadow table named "%_vocab" (where the % is replaced by the name of
** the virtual table; Ex: "demo_vocab" for the "demo" virtual table) is
** constructed with these columns:
**
**    id            The unique id (INTEGER PRIMARY KEY)
**
**    rank          The rank of word.
**
**    langid        The language id for this entry.
**
**    word          The original UTF8 text of the vocabulary word
**
**    k1            The word transliterated into lower-case ASCII.  
**                  There is a standard table of mappings from non-ASCII
**                  characters into ASCII.  Examples: "æ" -> "ae",
**                  "þ" -> "th", "ß" -> "ss", "á" -> "a", ...  The
**                  accessory function spellfix1_translit(X) will do
**                  the non-ASCII to ASCII mapping.  The built-in lower(X)
**                  function will convert to lower-case.  Thus:
**                  k1 = lower(spellfix1_translit(word)).
**
**    k2            This field holds a phonetic code derived from k1.  Letters
**                  that have similar sounds are mapped into the same symbol.
**                  For example, all vowels and vowel clusters become the
**                  single symbol "A".  And the letters "p", "b", "f", and
**                  "v" all become "B".  All nasal sounds are represented
**                  as "N".  And so forth.  The mapping is base on
**                  ideas found in Soundex, Metaphone, and other
**                  long-standing phonetic matching systems.  This key can
**                  be generated by the function spellfix1_phonehash(X).  
**                  Hence: k2 = spellfix1_phonehash(k1)
**
** There is also a function for computing the Wagner edit distance or the
** Levenshtein distance between a pattern and a word.  This function
** is exposed as spellfix1_editdist(X,Y).  The edit distance function
** returns the "cost" of converting X into Y.  Some transformations
** cost more than others.  Changing one vowel into a different vowel,
** for example is relatively cheap, as is doubling a constant, or
** omitting the second character of a double-constant.  Other transformations
** or more expensive.  The idea is that the edit distance function returns
** a low cost of words that are similar and a higher cost for words
** that are futher apart.  In this implementation, the maximum cost
** of any single-character edit (delete, insert, or substitute) is 100,
** with lower costs for some edits (such as transforming vowels).
**
** The "score" for a comparison is the edit distance between the pattern
** and the word, adjusted down by the base-2 logorithm of the word rank.
** For example, a match with distance 100 but rank 1000 would have a
** score of 122 (= 100 - log2(1000) + 32) where as a match with distance
** 100 with a rank of 1 would have a score of 131 (100 - log2(1) + 32).
** (NB:  The constant 32 is added to each score to keep it from going
** negative in case the edit distance is zero.)  In this way, frequently
** used words get a slightly lower cost which tends to move them toward
** the top of the list of alternative spellings.
**
** A straightforward implementation of a spelling corrector would be
** to compare the search term against every word in the vocabulary
** and select the 20 with the lowest scores.  However, there will 
** typically be hundreds of thousands or millions of words in the
** vocabulary, and so this approach is not fast enough.
**
** Suppose the term that is being spell-corrected is X.  To limit
** the search space, X is converted to a k2-like key using the
** equivalent of:
**
**    key = spellfix1_phonehash(lower(spellfix1_translit(X)))
**
** This key is then limited to "scope" characters.  The default scope
** value is 4, but an alternative scope can be specified using the
** "scope=N" term in the WHERE clause.  After the key has been truncated,
** the edit distance is run against every term in the vocabulary that
** has a k2 value that begins with the abbreviated key.
**
** For example, suppose the input word is "Paskagula".  The phonetic 
** key is "BACACALA" which is then truncated to 4 characters "BACA".
** The edit distance is then run on the 4980 entries (out of
** 272,597 entries total) of the vocabulary whose k2 values begin with
** BACA, yielding "Pascagoula" as the best match.
** 
** Only terms of the vocabulary with a matching langid are searched.
** Hence, the same table can contain entries from multiple languages
** and only the requested language will be used.  The default langid
** is 0.
**
** DEALING WITH UNUSUAL AND DIFFICULT SPELLINGS
**
** The algorithm above works quite well for most cases, but there are
** exceptions.  These exceptions can be dealt with by making additional
** entries in the virtual table using the "soundslike" column.
**
** For example, many words of Greek origin begin with letters "ps" where
** the "p" is silent.  Ex:  psalm, pseudonym, psoriasis, psyche.  In
** another example, many Scottish surnames can be spelled with an
** initial "Mac" or "Mc".  Thus, "MacKay" and "McKay" are both pronounced
** the same.
**
** Accommodation can be made for words that are not spelled as they
** sound by making additional entries into the virtual table for the
** same word, but adding an alternative spelling in the "soundslike"
** column.  For example, the canonical entry for "psalm" would be this:
**
**   INSERT INTO demo(word) VALUES('psalm');
**
** To enhance the ability to correct the spelling of "salm" into
** "psalm", make an addition entry like this:
**
**   INSERT INTO demo(word,soundslike) VALUES('psalm','salm');
**
** It is ok to make multiple entries for the same word as long as
** each entry has a different soundslike value.  Note that if no
** soundslike value is specified, the soundslike defaults to the word
** itself.
**
** Listed below are some cases where it might make sense to add additional
** soundslike entries.  The specific entries will depend on the application
** and the target language.
**
**   *   Silent "p" in words beginning with "ps":  psalm, psyche
**
**   *   Silent "p" in words beginning with "pn":  pneumonia, pneumatic
**
**   *   Silent "p" in words beginning with "pt":  pterodactyl, ptolemaic
**
**   *   Silent "d" in words beginning with "dj":  djinn, Djikarta
**
**   *   Silent "k" in words beginning with "kn":  knight, Knuthson
**
**   *   Silent "g" in words beginning with "gn":  gnarly, gnome, gnat
**
**   *   "Mac" versus "Mc" beginning Scottish surnames
**
**   *   "Tch" sounds in Slavic words:  Tchaikovsky vs. Chaykovsky
**
**   *   The letter "j" pronounced like "h" in Spanish:  LaJolla
**
**   *   Words beginning with "wr" versus "r":  write vs. rite
**
**   *   Miscellanous problem words such as "debt", "tsetse",
**       "Nguyen", "Van Nuyes".
*/
#if SQLITE_CORE
# include "sqliteInt.h"
#else
# include <string.h>
# include <stdio.h>
# include <stdlib.h>
................................................................................
**   4   'D'       Alveolar stops:  D T
**   5   'H'       Letter H at the beginning of a word
**   6   'L'       Glide:  L
**   7   'R'       Semivowel:  R
**   8   'M'       Nasals:  M N
**   9   'W'       Letter W at the beginning of a word
**   10  'Y'       Letter Y at the beginning of a word.
**   11  '9'       A digit: 0 1 2 3 4 5 6 7 8 9
**   12  ' '       White space
**   13  '?'       Other.
*/
#define CCLASS_SILENT         0
#define CCLASS_VOWEL          1
#define CCLASS_B              2
#define CCLASS_C              3
................................................................................
      case 'g': 
      case 'k': {
        if( zIn[1]=='n' ){ zIn++; nIn--; }
        break;
      }
    }
  }
  if( zIn[0]=='k' && zIn[1]=='n' ){ zIn++, nIn--; }
  for(i=0; i<nIn; i++){
    unsigned char c = zIn[i];
    if( i+1<nIn ){
      if( c=='w' && zIn[i+1]=='r' ) continue;
      if( c=='d' && (zIn[i+1]=='j' || zIn[i+1]=='g') ) continue;
      if( i+2<nIn ){
        if( c=='t' && zIn[i+1]=='c' && zIn[i+2]=='h' ) continue;
................................................................................
    /* differ only in case */
    return 0;
  }
  classFrom = characterClass(cPrev, cFrom);
  classTo = characterClass(cPrev, cTo);
  if( classFrom==classTo ){
    /* Same character class */
    return classFrom=='A' ? 25 : 40;
  }
  if( classFrom>=CCLASS_B && classFrom<=CCLASS_Y
      && classTo>=CCLASS_B && classTo<=CCLASS_Y ){
    /* Convert from one consonant to another, but in a different class */
    return 75;
  }
  /* Any other subsitution */
................................................................................
**
** If pnMatch is not NULL, then *pnMatch is set to the number of bytes
** of zB that matched the pattern in zA. If zA does not end with a '*',
** then this value is always the number of bytes in zB (i.e. strlen(zB)).
** If zA does end in a '*', then it is the number of bytes in the prefix
** of zB that was deemed to match zA.
*/
static int editdist1(const char *zA, const char *zB, int iLangId, int *pnMatch){
  int nA, nB;            /* Number of characters in zA[] and zB[] */
  int xA, xB;            /* Loop counters for zA[] and zB[] */
  char cA, cB;           /* Current character of zA and zB */
  char cAprev, cBprev;   /* Previous character of zA and zB */
  char cAnext, cBnext;   /* Next character in zA and zB */
  int d;                 /* North-west cost value */
  int dc = 0;            /* North-west character value */
................................................................................

#if 0
  printf("A=\"%s\" B=\"%s\" dc=%c\n", zA, zB, dc?dc:' ');
#endif

  /* Verify input strings and measure their lengths */
  for(nA=0; zA[nA]; nA++){
    if( zA[nA]>127 ) return -2;
  }
  for(nB=0; zB[nB]; nB++){
    if( zB[nB]>127 ) return -2;
  }

  /* Special processing if either string is empty */
  if( nA==0 ){
    cBprev = dc;
    for(xB=res=0; (cB = zB[xB])!=0; xB++){
      res += insertOrDeleteCost(cBprev, cB, zB[xB+1])/FINAL_INS_COST_DIV;
................................................................................
      if( m[xB]<res ){
        res = m[xB];
        if( pnMatch ) *pnMatch = xB+nMatch;
      }
    }
  }else{
    res = m[nB];


    if( pnMatch ) *pnMatch = -1;
  }
  sqlite3_free(toFree);
  return res;
}

/*
** Function:    editdist(A,B)
**              editdist(A,B,langid)
**
** Return the cost of transforming string A into string B.  Both strings
** must be pure ASCII text.  If A ends with '*' then it is assumed to be
** a prefix of B and extra characters on the end of B have minimal additional
** cost.
*/
static void editdistSqlFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  int langid = argc==2 ? 0 : sqlite3_value_int(argv[2]);
  int res = editdist1(
                    (const char*)sqlite3_value_text(argv[0]),
                    (const char*)sqlite3_value_text(argv[1]),
                    langid, 0);
  if( res<0 ){
    if( res==(-3) ){
      sqlite3_result_error_nomem(context);
    }else if( res==(-2) ){
      sqlite3_result_error(context, "non-ASCII input to editdist()", -1);
    }else{
      sqlite3_result_error(context, "NULL input to editdist()", -1);
................................................................................
*/
static int editDist3ConfigLoad(
  EditDist3Config *p,      /* The edit distance configuration to load */
  sqlite3 *db,            /* Load from this database */
  const char *zTable      /* Name of the table from which to load */
){
  sqlite3_stmt *pStmt;
  int rc;
  char *zSql;
  int iLangPrev = -9999;
  EditDist3Lang *pLang;

  zSql = sqlite3_mprintf("SELECT iLang, cFrom, cTo, iCost"
                         " FROM \"%w\" WHERE iLang>=0 ORDER BY iLang", zTable);
  if( zSql==0 ) return SQLITE_NOMEM;
................................................................................
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqlite3_free(zSql);
  if( rc ) return rc;
  editDist3ConfigClear(p);
  while( sqlite3_step(pStmt)==SQLITE_ROW ){
    int iLang = sqlite3_column_int(pStmt, 0);
    const char *zFrom = (const char*)sqlite3_column_text(pStmt, 1);
    int nFrom = sqlite3_column_bytes(pStmt, 1);
    const char *zTo = (const char*)sqlite3_column_text(pStmt, 2);
    int nTo = sqlite3_column_bytes(pStmt, 2);
    int iCost = sqlite3_column_int(pStmt, 3);



    if( nFrom>100 || nFrom<0 || nTo>100 || nTo<0 ) continue;
    if( iCost<0 ) continue;
    if( iLang!=iLangPrev ){
      EditDist3Lang *pNew;
      p->nLang++;
      pNew = sqlite3_realloc(p->a, p->nLang*sizeof(p->a[0]));
      if( pNew==0 ){ rc = SQLITE_NOMEM; break; }
      p->a = pNew;
      pLang = &p->a[p->nLang-1];

      pLang->iLang = iLang;
      pLang->iInsCost = 100;
      pLang->iDelCost = 100;
      pLang->iSubCost = 200;
      pLang->pCost = 0;
      iLangPrev = iLang;
    }
    if( nFrom==1 && zFrom[0]=='?' && nTo==0 ){
      pLang->iDelCost = iCost;
    }else if( nFrom==0 && nTo==1 && zTo[0]=='?' ){
      pLang->iInsCost = iCost;
................................................................................
      pCost->iCost = iCost;
      memcpy(pCost->a, zFrom, nFrom);
      memcpy(pCost->a + nFrom, zTo, nTo);
      pCost->pNext = pLang->pCost;
      pLang->pCost = pCost; 
    }
  }
  sqlite3_finalize(pStmt);

  return rc;
}

/*
** Return the length (in bytes) of a utf-8 character.  Or return a maximum
** of N.
*/
................................................................................
}

/*
** Return TRUE (non-zero) of the To side of the given cost matches
** the given string.
*/
static int matchFrom(EditDist3Cost *p, const char *z, int n){
  if( p->nFrom>n ) return 0;
  if( memcmp(p->a, z, p->nFrom)!=0 ) return 0;
  return 1;
}

/*
** Return TRUE (non-zero) of the next FROM character and the next TO
** character are the same.
................................................................................
  const char *z,
  int n
){
  EditDist3FromString *pStr;
  EditDist3Cost *p;
  int i;


  if( n<0 ) n = (int)strlen(z);
  pStr = sqlite3_malloc( sizeof(*pStr) + sizeof(pStr->a[0])*n + n + 1 );
  if( pStr==0 ) return 0;
  pStr->a = (EditDist3From*)&pStr[1];

  pStr->n = n;
  pStr->z = (char*)&pStr->a[n];
  memcpy(pStr->z, z, n+1);
  if( n && z[n-1]=='*' ){
    pStr->isPrefix = 1;
    n--;
    pStr->n--;
................................................................................
      pStr = 0;
      break;
    }
  }
  return pStr;
}

#if 0 /* No longer used */
/*
** Return the number of bytes in the common prefix of two UTF8 strings.
** Only complete characters are considered.
*/
static int editDist3PrefixLen(const char *z1, const char *z2){
  int n = 0;
  while( z1[n] && z1[n]==z2[n] ){ n++; }
  while( n && (z1[n]&0xc0)==0x80 ){ n--; }
  return n;
}

/*
** Return the number of bytes in the common suffix of two UTF8 strings.
** Only complete characters are considered.
*/
static int editDist3SuffixLen(const char *z1, int n1, const char *z2, int n2){
  int origN1 = n1;
  while( n1>0 && n2>0 && z1[n1-1]==z2[n2-1] ){ n1--; n2--; }
  while( n1<origN1 && (z1[n1]&0xc0)==0x80 ){ n1++; n2++; }
  return origN1 - n1;
}
#endif /* 0 */

/*
** Update entry m[i] such that it is the minimum of its current value
** and m[j]+iCost.
**
** If the iCost is 1,000,000 or greater, then consider the cost to be
** infinite and skip the update.
*/
................................................................................
  EditDist3FromString f = *pFrom;
  EditDist3To *a2;
  unsigned int *m;
  int szRow;
  EditDist3Cost *p;
  int res;

#if 0
  /* Remove comment prefix and suffix */
  n = editDist3PrefixLen(f.z, z2);
  if( f.n==n2 && n2==n ) return 0;  /* Identical strings */
  f.n -= n;
  f.z += n;
  f.a += n;
  n2 -= n;
  z2 += n;
  if( f.isPrefix==0 ){
    n = editDist3SuffixLen(f.z, f.n, z2, n2);
    f.n -= n;
    n2 -= n;
  }
#endif

  /* allocate the Wagner matrix and the aTo[] array for the TO string */
  n = (f.n+1)*(n2+1);
  n = (n+1)&~1;
  m = sqlite3_malloc( n*sizeof(m[0]) + sizeof(a2[0])*n2 );
  if( m==0 ) return -1;            /* Out of memory */
  a2 = (EditDist3To*)&m[n];
  memset(a2, 0, sizeof(a2[0])*n2);
................................................................................
        if( matchTo(p, z2+i2, n2-i2) ){
          updateCost(m, cxd+p->nFrom+szRow*p->nTo, cxd, p->iCost);
        }
      }
    }
  }

#if 0
  printf("         ^");
  for(i1=0; i1<f.n; i1++) printf(" %c-%2x", f.z[i1], f.z[i1]&0xff);
  printf("\n   ^:");
  for(i1=0; i1<szRow; i1++){
    int v = m[i1];
    if( v>9999 ) printf(" ****");
    else         printf(" %4d", v);
................................................................................
    pFrom = editDist3FromStringNew(pLang, zA, nA);
    if( pFrom==0 ){
      sqlite3_result_error_nomem(context);
      return;
    }
    dist = editDist3Core(pFrom, zB, nB, pLang, 0);
    editDist3FromStringDelete(pFrom);



    sqlite3_result_int(context, dist);

  } 
}

/*
** Register the editDist3 function with SQLite
*/
static int editDist3Install(sqlite3 *db){
................................................................................

/*
** Return the value of the first UTF-8 character in the string.
*/
static int utf8Read(const unsigned char *z, int n, int *pSize){
  int c, i;

  if( n==0 ){


    c = i = 0;
  }else{
    c = z[0];
    i = 1;
    if( c>=0xc0 ){
      c = sqlite3Utf8Trans1[c-0xc0];
      while( i<n && (z[i] & 0xc0)==0x80 ){
................................................................................
** The returned string might contain more characters than the input.
**
** Space to hold the returned string comes from sqlite3_malloc() and
** should be freed by the caller.
*/
static unsigned char *transliterate(const unsigned char *zIn, int nIn){
  unsigned char *zOut = sqlite3_malloc( nIn*4 + 1 );
  int i, c, sz, nOut;
  if( zOut==0 ) return 0;
  i = nOut = 0;
  while( i<nIn ){
    c = utf8Read(zIn, nIn, &sz);
    zIn += sz;
    nIn -= sz;
    if( c<=127 ){
      zOut[nOut++] = c;
    }else{
      int xTop, xBtm, x;
................................................................................
  }
  sqlite3_result_int(context, res);
}

/* End transliterate
******************************************************************************
******************************************************************************
** Begin Polloc & Zamora SPEEDCOP style keying functions.
*/
/*
** The Pollock & Zamora skeleton function.  Move all consonants to the
** front and all vowels to the end, removing duplicates.  Except if the
** first letter is a vowel then it remains as the first letter.
*/
static void pollockSkeletonKey(const char *zIn, char *zOut){
  int i, j;
  unsigned char c;
  char seen[26];
  static const unsigned char isVowel[] = { 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0,
    0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0 };
  memset(seen, 0, sizeof(seen));
  for(i=j=0; (c = (unsigned char)zIn[i])!=0; i++){
    if( c<'a' || c>'z' ) continue;
    if( j>0 || isVowel[c-'a'] ) continue;
    if( seen[c-'a'] ) continue;
    seen[c-'a'] = 1;
    zOut[j++] = c;
  }
  for(i=0; (c = (unsigned char)zIn[i])!=0; i++){
    if( c<'a' || c>'z' ) continue;
    if( seen[c-'a'] ) continue;
    if( !isVowel[c-'a'] ) continue;
    seen[c-'a'] = 1;
    zOut[j++] = c;
  }
  zOut[j] = 0;
}

/*
** Function:    pollock_skeleton(X)
**
** Return the Pollock and Zamora skeleton key for a string X of all
** lower-case letters.
*/
static void pollockSkeletonSqlFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const char *zIn = (const char*)sqlite3_value_text(argv[0]);
  int nIn = sqlite3_value_bytes(argv[0]);
  char *zOut;
  if( zIn ){
    zOut = sqlite3_malloc( nIn + 1 );
    if( zOut==0 ){
      sqlite3_result_error_nomem(context);
    }else{
      pollockSkeletonKey(zIn, zOut);
      sqlite3_result_text(context, (char*)zOut, -1, sqlite3_free);
    }
  }
}  

/*
** The Pollock & Zamora omission key.
**
** The key consists of unique consonants in the following order:
**
**         jkqxzvwybfmgpdhclntsr
**
** These are followed by unique vowels in input order.
*/
static void pollockOmissionKey(const char *zIn, char *zOut){
  int i, j;
  unsigned char c;
  char seen[26];
  static const unsigned char isVowel[] = { 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0,
    0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0 };
  static const unsigned char constOrder[] = "jkqxzvwybfmgpdhclntsr";

  memset(seen, 0, sizeof(seen));
  for(i=j=0; (c = (unsigned char)zIn[i])!=0; i++){
    if( c<'a' || c>'z' ) continue;
    if( isVowel[c-'a'] ) continue;
    if( seen[c-'a'] ) continue;
    seen[c-'a'] = 1;
  }
  for(i=0; (c = constOrder[i])!=0; i++){
    if( seen[c-'a'] ) zOut[j++] = c;
  }
  for(i=0; (c = (unsigned char)zIn[i])!=0; i++){
    if( c<'a' || c>'z' ) continue;
    if( seen[c-'a'] ) continue;
    if( !isVowel[c-'a'] ) continue;
    seen[c-'a'] = 1;
    zOut[j++] = c;
  }
  zOut[j] = 0;
}

/*
** Function:    pollock_omission(X)
**
** Return the Pollock and Zamora omission key for a string X of all
** lower-case letters.
*/
static void pollockOmissionSqlFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){
  const char *zIn = (const char*)sqlite3_value_text(argv[0]);
  int nIn = sqlite3_value_bytes(argv[0]);
  char *zOut;
  if( zIn ){
    zOut = sqlite3_malloc( nIn + 1 );
    if( zOut==0 ){
      sqlite3_result_error_nomem(context);
    }else{
      pollockOmissionKey(zIn, zOut);
      sqlite3_result_text(context, (char*)zOut, -1, sqlite3_free);
    }
  }
}  


/* End SPEEDCOP keying functions
******************************************************************************
******************************************************************************
** Begin spellfix1 virtual table.
*/

/* Maximum length of a phonehash used for querying the shadow table */
#define SPELLFIX_MX_HASH  8

/* Maximum number of hash strings to examine per query */
#define SPELLFIX_MX_RUN   8

typedef struct spellfix1_vtab spellfix1_vtab;
typedef struct spellfix1_cursor spellfix1_cursor;

/* Fuzzy-search virtual table object */
struct spellfix1_vtab {
  sqlite3_vtab base;         /* Base class - must be first */
................................................................................
struct spellfix1_cursor {
  sqlite3_vtab_cursor base;    /* Base class - must be first */
  spellfix1_vtab *pVTab;       /* The table to which this cursor belongs */
  char *zPattern;              /* rhs of MATCH clause */
  int nRow;                    /* Number of rows of content */
  int nAlloc;                  /* Number of allocated rows */
  int iRow;                    /* Current row of content */
  int iLang;                   /* Value of the lang= constraint */
  int iTop;                    /* Value of the top= constraint */
  int iScope;                  /* Value of the scope= constraint */
  int nSearch;                 /* Number of vocabulary items checked */

  struct spellfix1_row {       /* For each row of content */
    sqlite3_int64 iRowid;         /* Rowid for this row */
    char *zWord;                  /* Text for this row */
    int iRank;                    /* Rank for this row */
    int iDistance;                /* Distance from pattern for this row */
    int iScore;                   /* Score for sorting */
    int iMatchlen;                /* Value of matchlen column (or -1) */
................................................................................
  char *zOut;
  int i, j;
  char c;
  while( isspace(zIn[0]) ) zIn++;
  zOut = sqlite3_mprintf("%s", zIn);
  if( zOut==0 ) return 0;
  i = (int)strlen(zOut);

  while( i>0 && isspace(zOut[i-1]) ){ i--; }

  zOut[i] = 0;
  c = zOut[0];
  if( c=='\'' || c=='"' ){
    for(i=1, j=0; zOut[i]; i++){
      zOut[j++] = zOut[i];
      if( zOut[i]==c ){
        if( zOut[i+1]==c ){
          i++;
        }else{
          zOut[j-1] = 0;
          break;
................................................................................
  const char *zModule = argv[0];
  const char *zDbName = argv[1];
  const char *zTableName = argv[2];
  int nDbName;
  int rc = SQLITE_OK;
  int i;

  if( argc<3 ){
    *pzErr = sqlite3_mprintf(
        "%s: wrong number of CREATE VIRTUAL TABLE arguments", argv[0]
    );
    rc = SQLITE_ERROR;
  }else{
    nDbName = strlen(zDbName);
    pNew = sqlite3_malloc( sizeof(*pNew) + nDbName + 1);
    if( pNew==0 ){
      rc = SQLITE_NOMEM;
    }else{
      memset(pNew, 0, sizeof(*pNew));
      pNew->zDbName = (char*)&pNew[1];
      memcpy(pNew->zDbName, zDbName, nDbName+1);
      pNew->zTableName = sqlite3_mprintf("%s", zTableName);
      pNew->db = db;
      if( pNew->zTableName==0 ){
        rc = SQLITE_NOMEM;
      }else{
        rc = sqlite3_declare_vtab(db, 
             "CREATE TABLE x(word,rank,distance,langid, "
             "score, matchlen, phonehash, "
             "top HIDDEN, scope HIDDEN, srchcnt HIDDEN, "
             "soundslike HIDDEN, command HIDDEN)"
        );
#define SPELLFIX_COL_WORD            0
#define SPELLFIX_COL_RANK            1
#define SPELLFIX_COL_DISTANCE        2
#define SPELLFIX_COL_LANGID          3
#define SPELLFIX_COL_SCORE           4
#define SPELLFIX_COL_MATCHLEN        5
#define SPELLFIX_COL_PHONEHASH       6
#define SPELLFIX_COL_TOP             7
#define SPELLFIX_COL_SCOPE           8
#define SPELLFIX_COL_SRCHCNT         9
#define SPELLFIX_COL_SOUNDSLIKE     10
#define SPELLFIX_COL_COMMAND        11
      }
      if( rc==SQLITE_OK && isCreate ){
        sqlite3_uint64 r;
        spellfix1DbExec(&rc, db,
           "CREATE TABLE IF NOT EXISTS \"%w\".\"%w_vocab\"(\n"
           "  id INTEGER PRIMARY KEY,\n"
           "  rank INT,\n"
           "  langid INT,\n"
           "  word TEXT,\n"
           "  k1 TEXT,\n"
           "  k2 TEXT\n"
           ");\n",
           zDbName, zTableName
        );
        sqlite3_randomness(sizeof(r), &r);
        spellfix1DbExec(&rc, db,
           "CREATE INDEX IF NOT EXISTS \"%w\".\"%w_index_%llx\" "
              "ON \"%w_vocab\"(langid,k2);",
           zDbName, zModule, r, zTableName
        );
      }
      for(i=3; rc==SQLITE_OK && i<argc; i++){
        if( memcmp(argv[i],"edit_cost_table=",16)==0 && pNew->zCostTable==0 ){
          pNew->zCostTable = spellfix1Dequote(&argv[i][16]);
          if( pNew->zCostTable==0 ) rc = SQLITE_NOMEM;
          continue;
        }

        rc = SQLITE_ERROR; 
      }
    }
  }





  *ppVTab = (sqlite3_vtab *)pNew;

  return rc;
}

/*
** The xConnect and xCreate methods
*/
static int spellfix1Connect(
................................................................................
  int i;
  for(i=0; i<pCur->nRow; i++){
    sqlite3_free(pCur->a[i].zWord);
  }
  pCur->nRow = 0;
  pCur->iRow = 0;
  pCur->nSearch = 0;




}

/*
** Resize the cursor to hold up to N rows of content
*/
static void spellfix1ResizeCursor(spellfix1_cursor *pCur, int N){
  struct spellfix1_row *aNew;
................................................................................
      iDistTerm = i;
    }
  }
  if( iPlan&1 ){
    int idx = 2;
    pIdxInfo->idxNum = iPlan;
    if( pIdxInfo->nOrderBy==1
     && pIdxInfo->aOrderBy[0].iColumn==4
     && pIdxInfo->aOrderBy[0].desc==0
    ){
      pIdxInfo->orderByConsumed = 1;  /* Default order by iScore */
    }
    if( iPlan&2 ){
      pIdxInfo->aConstraintUsage[iLangTerm].argvIndex = idx++;
      pIdxInfo->aConstraintUsage[iLangTerm].omit = 1;
................................................................................
  int iScope = p->iScope;
  spellfix1_cursor *pCur = p->pCur;
  sqlite3_stmt *pStmt = p->pStmt;
  char zHash1[SPELLFIX_MX_HASH];
  char zHash2[SPELLFIX_MX_HASH];
  char *zClass;
  int nClass;


  if( pCur->a==0 || p->rc ) return;   /* Prior memory allocation failure */
  if( p->nRun>=SPELLFIX_MX_RUN ) return;
  zClass = (char*)phoneticHash((unsigned char*)zQuery, nQuery);
  if( zClass==0 ){
    p->rc = SQLITE_NOMEM;
    return;
  }
  nClass = strlen(zClass);
  if( nClass>SPELLFIX_MX_HASH-2 ){
................................................................................
  }
  memcpy(zHash1, zClass, iScope);
  sqlite3_free(zClass);
  zHash1[iScope] = 0;
  memcpy(zHash2, zHash1, iScope);
  zHash2[iScope] = 'Z';
  zHash2[iScope+1] = 0;

  for(i=0; i<p->nRun; i++){
    if( strcmp(p->azPrior[i], zHash1)==0 ) return;
  }


  memcpy(p->azPrior[p->nRun++], zHash1, iScope+1);
  sqlite3_bind_text(pStmt, 1, zHash1, -1, SQLITE_STATIC);
  sqlite3_bind_text(pStmt, 2, zHash2, -1, SQLITE_STATIC);





  for(i=0; i<pCur->nRow; i++){
    if( pCur->a[i].iScore>iWorst ){
      iWorst = pCur->a[i].iScore;
      idxWorst = i;
    }
  }

  while( sqlite3_step(pStmt)==SQLITE_ROW ){
    int iMatchlen = -1;
    iRank = sqlite3_column_int(pStmt, 2);
    if( p->pMatchStr3 ){
      int nWord = sqlite3_column_bytes(pStmt, 1);
      zWord = (const char*)sqlite3_column_text(pStmt, 1);
      iDist = editDist3Core(p->pMatchStr3, zWord, nWord, p->pLang, &iMatchlen);
    }else{
      zK1 = (const char*)sqlite3_column_text(pStmt, 3);
      if( zK1==0 ) continue;
      iDist = editdist1(p->zPattern, zK1, pCur->iLang, 0);




    }
    pCur->nSearch++;
    iScore = spellfix1Score(iDist,iRank);
    if( p->iMaxDist>=0 ){
      if( iDist>p->iMaxDist ) continue;
      if( pCur->nRow>=pCur->nAlloc-1 ){
        spellfix1ResizeCursor(pCur, pCur->nAlloc*2 + 10);
................................................................................
    }else if( iScore<iWorst ){
      idx = idxWorst;
      sqlite3_free(pCur->a[idx].zWord);
    }else{
      continue;
    }
    pCur->a[idx].zWord = sqlite3_mprintf("%s", sqlite3_column_text(pStmt, 1));




    pCur->a[idx].iRowid = sqlite3_column_int64(pStmt, 0);
    pCur->a[idx].iRank = iRank;
    pCur->a[idx].iDistance = iDist;
    pCur->a[idx].iScore = iScore;
    pCur->a[idx].iMatchlen = iMatchlen;
    memcpy(pCur->a[idx].zHash, zHash1, iScope+1);
    if( pCur->nRow<pCur->nAlloc ) pCur->nRow++;
................................................................................
        if( iWorst<iScore ){
          iWorst = iScore;
          idxWorst = i;
        }
      }
    }
  }
  sqlite3_reset(pStmt);

}

/*
** This version of the xFilter method work if the MATCH term is present
** and we are doing a scan.
*/
static int spellfix1FilterForMatch(
................................................................................
  EditDist3FromString *pMatchStr3 = 0; /* zMatchThis as an editdist string */
  char *zPattern;                    /* Transliteration of zMatchThis */
  int nPattern;                      /* Length of zPattern */
  int iLimit = 20;                   /* Max number of rows of output */
  int iScope = 3;                    /* Use this many characters of zClass */
  int iLang = 0;                     /* Language code */
  char *zSql;                        /* SQL of shadow table query */
  sqlite3_stmt *pStmt;               /* Shadow table query */
  int rc;                            /* Result code */
  int idx = 1;                       /* Next available filter parameter */
  spellfix1_vtab *p = pCur->pVTab;   /* The virtual table that owns pCur */
  MatchQuery x;                      /* For passing info to RunQuery() */

  /* Load the cost table if we have not already done so */
  if( p->zCostTable!=0 && p->pConfig3==0 ){
................................................................................
  spellfix1ResetCursor(pCur);
  spellfix1ResizeCursor(pCur, iLimit);
  zMatchThis = sqlite3_value_text(argv[0]);
  if( zMatchThis==0 ) return SQLITE_OK;
  if( p->pConfig3 ){
    x.pLang = editDist3FindLang(p->pConfig3, iLang);
    pMatchStr3 = editDist3FromStringNew(x.pLang, (const char*)zMatchThis, -1);




  }else{
    x.pLang = 0;
  }
  zPattern = (char*)transliterate(zMatchThis, sqlite3_value_bytes(argv[0]));
  sqlite3_free(pCur->zPattern);
  pCur->zPattern = zPattern;
  if( zPattern==0 ) return SQLITE_NOMEM;



  nPattern = strlen(zPattern);
  if( zPattern[nPattern-1]=='*' ) nPattern--;
  zSql = sqlite3_mprintf(
     "SELECT id, word, rank, k1"
     "  FROM \"%w\".\"%w_vocab\""
     " WHERE langid=%d AND k2>=?1 AND k2<?2",
     p->zDbName, p->zTableName, iLang
  );





  rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, 0);
  sqlite3_free(zSql);
  pCur->iLang = iLang;
  x.pCur = pCur;
  x.pStmt = pStmt;
  x.zPattern = zPattern;
  x.nPattern = nPattern;
................................................................................
  x.iLang = iLang;
  x.rc = rc;
  x.pConfig3 = p->pConfig3;
  if( x.rc==SQLITE_OK ){
    spellfix1RunQuery(&x, zPattern, nPattern);
  }

#if 0
  /* Convert "ght" to "t" in the original pattern and try again */
  if( x.rc==SQLITE_OK ){
    int i, j;                         /* Loop counters */
    char zQuery[50];                  /* Space for alternative query string */
    for(i=j=0; i<nPattern && i<sizeof(zQuery)-1; i++){
      char c = zPattern[i];
      if( c=='g' && i<nPattern-2 && zPattern[i+1]=='h' && zPattern[i+2]=='t' ){
        i += 2;
        c= 't';
      }
      zQuery[j++] = c;
    }
    zQuery[j] = 0;
    if( j<i ){
      spellfix1RunQuery(&x, zQuery, j);
    }
  }
#endif

  if( pCur->a ){
    qsort(pCur->a, pCur->nRow, sizeof(pCur->a[0]), spellfix1RowCompare);
    pCur->iTop = iLimit;
    pCur->iScope = iScope;


  }


  sqlite3_finalize(pStmt);
  editDist3FromStringDelete(pMatchStr3);
  return pCur->a ? x.rc : SQLITE_NOMEM;

}

/*
** This version of xFilter handles a full-table scan case
*/
static int spellfix1FilterForFullScan(
  spellfix1_cursor *pCur,
  int idxNum,
  int argc,
  sqlite3_value **argv
){



  spellfix1ResetCursor(pCur);
  spellfix1ResizeCursor(pCur, 0);



  return SQLITE_OK;











}


/*
** Called to "rewind" a cursor back to the beginning so that
** it starts its output over again.  Always called at least once
** prior to any spellfix1Column, spellfix1Rowid, or spellfix1Eof call.
................................................................................


/*
** Advance a cursor to its next row of output
*/
static int spellfix1Next(sqlite3_vtab_cursor *cur){
  spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
  if( pCur->iRow < pCur->nRow ) pCur->iRow++;







  return SQLITE_OK;
}

/*
** Return TRUE if we are at the end-of-file
*/
static int spellfix1Eof(sqlite3_vtab_cursor *cur){
................................................................................
  spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
  return pCur->iRow>=pCur->nRow;
}

/*
** Return columns from the current row.
*/
static int spellfix1Column(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){




  spellfix1_cursor *pCur = (spellfix1_cursor*)cur;








  switch( i ){
    case SPELLFIX_COL_WORD: {
      sqlite3_result_text(ctx, pCur->a[pCur->iRow].zWord, -1, SQLITE_STATIC);
      break;
    }
    case SPELLFIX_COL_RANK: {
      sqlite3_result_int(ctx, pCur->a[pCur->iRow].iRank);
................................................................................
        int nWord = strlen(zWord);

        if( nPattern>0 && pCur->zPattern[nPattern-1]=='*' ){
          char *zTranslit;
          int res;
          zTranslit = (char *)transliterate((unsigned char *)zWord, nWord);
          if( !zTranslit ) return SQLITE_NOMEM;
          res = editdist1(pCur->zPattern, zTranslit, pCur->iLang, &iMatchlen);
          sqlite3_free(zTranslit);
          if( res<0 ) return SQLITE_NOMEM;
          iMatchlen = translen_to_charlen(zWord, nWord, iMatchlen);
        }else{
          iMatchlen = utf8Charlen(zWord, nWord);
        }
      }
................................................................................
}

/*
** The rowid.
*/
static int spellfix1Rowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  spellfix1_cursor *pCur = (spellfix1_cursor*)cur;



  *pRowid = pCur->a[pCur->iRow].iRowid;

  return SQLITE_OK;
}

/*
** The xUpdate() method.
*/
static int spellfix1Update(
................................................................................
             iRank, iLang, zWord, zK1, zK2
      );
      *pRowid = sqlite3_last_insert_rowid(db);
    }else{
      rowid = sqlite3_value_int64(argv[0]);
      newRowid = *pRowid = sqlite3_value_int64(argv[1]);
      spellfix1DbExec(&rc, db,
             "UPDATE \"%w\".\"%w_vocab\" SET id=%lld, rank=%d, lang=%d,"
             " word=%Q, rank=%d, k1=%Q, k2=%Q WHERE id=%lld",
             p->zDbName, p->zTableName, newRowid, iRank, iLang,
             zWord, zK1, zK2, rowid
      );
    }
    sqlite3_free(zK1);
    sqlite3_free(zK2);
  }
................................................................................
  spellfix1DbExec(&rc, db, 
     "ALTER TABLE \"%w\".\"%w_vocab\" RENAME TO \"%w_vocab\"",
     p->zDbName, p->zTableName, zNewName
  );
  if( rc==SQLITE_OK ){
    sqlite3_free(p->zTableName);
    p->zTableName = zNewName;


  }
  return rc;
}


/*
** A virtual table module that provides fuzzy search.
................................................................................
static int spellfix1Register(sqlite3 *db){
  int nErr = 0;
  int i;
  nErr += sqlite3_create_function(db, "spellfix1_translit", 1, SQLITE_UTF8, 0,
                                  transliterateSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "spellfix1_editdist", 2, SQLITE_UTF8, 0,
                                  editdistSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "spellfix1_editdist", 3, SQLITE_UTF8, 0,
                                  editdistSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "spellfix1_phonehash", 1, SQLITE_UTF8, 0,
                                  phoneticHashSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "spellfix1_scriptcode", 1, SQLITE_UTF8, 0,
                                  scriptCodeSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "pollock_skeleton", 1, SQLITE_UTF8, 0,
                                  pollockSkeletonSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "pollock_omission", 1, SQLITE_UTF8, 0,
                                  pollockOmissionSqlFunc, 0, 0);
  nErr += sqlite3_create_module(db, "spellfix1", &spellfix1Module, 0);
  nErr += editDist3Install(db);

  /* Verify sanity of the translit[] table */
  for(i=0; i<sizeof(translit)/sizeof(translit[0])-1; i++){
    assert( translit[i].cFrom<translit[i+1].cFrom );
  }

**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
**
** This module implements the spellfix1 VIRTUAL TABLE that can be used
** to search a large vocabulary for close matches.  See separate
** documentation files (spellfix1.wiki and editdist3.wiki) for details.











































































































































































































































































*/
#if SQLITE_CORE
# include "sqliteInt.h"
#else
# include <string.h>
# include <stdio.h>
# include <stdlib.h>
................................................................................
**   4   'D'       Alveolar stops:  D T
**   5   'H'       Letter H at the beginning of a word
**   6   'L'       Glide:  L
**   7   'R'       Semivowel:  R
**   8   'M'       Nasals:  M N
**   9   'W'       Letter W at the beginning of a word
**   10  'Y'       Letter Y at the beginning of a word.
**   11  '9'       Digits: 0 1 2 3 4 5 6 7 8 9
**   12  ' '       White space
**   13  '?'       Other.
*/
#define CCLASS_SILENT         0
#define CCLASS_VOWEL          1
#define CCLASS_B              2
#define CCLASS_C              3
................................................................................
      case 'g': 
      case 'k': {
        if( zIn[1]=='n' ){ zIn++; nIn--; }
        break;
      }
    }
  }

  for(i=0; i<nIn; i++){
    unsigned char c = zIn[i];
    if( i+1<nIn ){
      if( c=='w' && zIn[i+1]=='r' ) continue;
      if( c=='d' && (zIn[i+1]=='j' || zIn[i+1]=='g') ) continue;
      if( i+2<nIn ){
        if( c=='t' && zIn[i+1]=='c' && zIn[i+2]=='h' ) continue;
................................................................................
    /* differ only in case */
    return 0;
  }
  classFrom = characterClass(cPrev, cFrom);
  classTo = characterClass(cPrev, cTo);
  if( classFrom==classTo ){
    /* Same character class */
    return 40;
  }
  if( classFrom>=CCLASS_B && classFrom<=CCLASS_Y
      && classTo>=CCLASS_B && classTo<=CCLASS_Y ){
    /* Convert from one consonant to another, but in a different class */
    return 75;
  }
  /* Any other subsitution */
................................................................................
**
** If pnMatch is not NULL, then *pnMatch is set to the number of bytes
** of zB that matched the pattern in zA. If zA does not end with a '*',
** then this value is always the number of bytes in zB (i.e. strlen(zB)).
** If zA does end in a '*', then it is the number of bytes in the prefix
** of zB that was deemed to match zA.
*/
static int editdist1(const char *zA, const char *zB, int *pnMatch){
  int nA, nB;            /* Number of characters in zA[] and zB[] */
  int xA, xB;            /* Loop counters for zA[] and zB[] */
  char cA, cB;           /* Current character of zA and zB */
  char cAprev, cBprev;   /* Previous character of zA and zB */
  char cAnext, cBnext;   /* Next character in zA and zB */
  int d;                 /* North-west cost value */
  int dc = 0;            /* North-west character value */
................................................................................

#if 0
  printf("A=\"%s\" B=\"%s\" dc=%c\n", zA, zB, dc?dc:' ');
#endif

  /* Verify input strings and measure their lengths */
  for(nA=0; zA[nA]; nA++){
    if( zA[nA]&0x80 ) return -2;
  }
  for(nB=0; zB[nB]; nB++){
    if( zB[nB]&0x80 ) return -2;
  }

  /* Special processing if either string is empty */
  if( nA==0 ){
    cBprev = dc;
    for(xB=res=0; (cB = zB[xB])!=0; xB++){
      res += insertOrDeleteCost(cBprev, cB, zB[xB+1])/FINAL_INS_COST_DIV;
................................................................................
      if( m[xB]<res ){
        res = m[xB];
        if( pnMatch ) *pnMatch = xB+nMatch;
      }
    }
  }else{
    res = m[nB];
    /* In the current implementation, pnMatch is always NULL if zA does
    ** not end in "*" */
    assert( pnMatch==0 );
  }
  sqlite3_free(toFree);
  return res;
}

/*
** Function:    editdist(A,B)

**
** Return the cost of transforming string A into string B.  Both strings
** must be pure ASCII text.  If A ends with '*' then it is assumed to be
** a prefix of B and extra characters on the end of B have minimal additional
** cost.
*/
static void editdistSqlFunc(
  sqlite3_context *context,
  int argc,
  sqlite3_value **argv
){

  int res = editdist1(
                    (const char*)sqlite3_value_text(argv[0]),
                    (const char*)sqlite3_value_text(argv[1]),
                    0);
  if( res<0 ){
    if( res==(-3) ){
      sqlite3_result_error_nomem(context);
    }else if( res==(-2) ){
      sqlite3_result_error(context, "non-ASCII input to editdist()", -1);
    }else{
      sqlite3_result_error(context, "NULL input to editdist()", -1);
................................................................................
*/
static int editDist3ConfigLoad(
  EditDist3Config *p,      /* The edit distance configuration to load */
  sqlite3 *db,            /* Load from this database */
  const char *zTable      /* Name of the table from which to load */
){
  sqlite3_stmt *pStmt;
  int rc, rc2;
  char *zSql;
  int iLangPrev = -9999;
  EditDist3Lang *pLang;

  zSql = sqlite3_mprintf("SELECT iLang, cFrom, cTo, iCost"
                         " FROM \"%w\" WHERE iLang>=0 ORDER BY iLang", zTable);
  if( zSql==0 ) return SQLITE_NOMEM;
................................................................................
  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
  sqlite3_free(zSql);
  if( rc ) return rc;
  editDist3ConfigClear(p);
  while( sqlite3_step(pStmt)==SQLITE_ROW ){
    int iLang = sqlite3_column_int(pStmt, 0);
    const char *zFrom = (const char*)sqlite3_column_text(pStmt, 1);
    int nFrom = zFrom ? sqlite3_column_bytes(pStmt, 1) : 0;
    const char *zTo = (const char*)sqlite3_column_text(pStmt, 2);
    int nTo = zTo ? sqlite3_column_bytes(pStmt, 2) : 0;
    int iCost = sqlite3_column_int(pStmt, 3);

    assert( zFrom!=0 || nFrom==0 );
    assert( zTo!=0 || nTo==0 );
    if( nFrom>100 || nTo>100 ) continue;
    if( iCost<0 ) continue;
    if( iLang!=iLangPrev ){
      EditDist3Lang *pNew;

      pNew = sqlite3_realloc(p->a, (p->nLang+1)*sizeof(p->a[0]));
      if( pNew==0 ){ rc = SQLITE_NOMEM; break; }
      p->a = pNew;
      pLang = &p->a[p->nLang];
      p->nLang++;
      pLang->iLang = iLang;
      pLang->iInsCost = 100;
      pLang->iDelCost = 100;
      pLang->iSubCost = 150;
      pLang->pCost = 0;
      iLangPrev = iLang;
    }
    if( nFrom==1 && zFrom[0]=='?' && nTo==0 ){
      pLang->iDelCost = iCost;
    }else if( nFrom==0 && nTo==1 && zTo[0]=='?' ){
      pLang->iInsCost = iCost;
................................................................................
      pCost->iCost = iCost;
      memcpy(pCost->a, zFrom, nFrom);
      memcpy(pCost->a + nFrom, zTo, nTo);
      pCost->pNext = pLang->pCost;
      pLang->pCost = pCost; 
    }
  }
  rc2 = sqlite3_finalize(pStmt);
  if( rc==SQLITE_OK ) rc = rc2;
  return rc;
}

/*
** Return the length (in bytes) of a utf-8 character.  Or return a maximum
** of N.
*/
................................................................................
}

/*
** Return TRUE (non-zero) of the To side of the given cost matches
** the given string.
*/
static int matchFrom(EditDist3Cost *p, const char *z, int n){
  assert( p->nFrom<=n );
  if( memcmp(p->a, z, p->nFrom)!=0 ) return 0;
  return 1;
}

/*
** Return TRUE (non-zero) of the next FROM character and the next TO
** character are the same.
................................................................................
  const char *z,
  int n
){
  EditDist3FromString *pStr;
  EditDist3Cost *p;
  int i;

  if( z==0 ) return 0;
  if( n<0 ) n = (int)strlen(z);
  pStr = sqlite3_malloc( sizeof(*pStr) + sizeof(pStr->a[0])*n + n + 1 );
  if( pStr==0 ) return 0;
  pStr->a = (EditDist3From*)&pStr[1];
  memset(pStr->a, 0, sizeof(pStr->a[0])*n);
  pStr->n = n;
  pStr->z = (char*)&pStr->a[n];
  memcpy(pStr->z, z, n+1);
  if( n && z[n-1]=='*' ){
    pStr->isPrefix = 1;
    n--;
    pStr->n--;
................................................................................
      pStr = 0;
      break;
    }
  }
  return pStr;
}

























/*
** Update entry m[i] such that it is the minimum of its current value
** and m[j]+iCost.
**
** If the iCost is 1,000,000 or greater, then consider the cost to be
** infinite and skip the update.
*/
................................................................................
  EditDist3FromString f = *pFrom;
  EditDist3To *a2;
  unsigned int *m;
  int szRow;
  EditDist3Cost *p;
  int res;

















  /* allocate the Wagner matrix and the aTo[] array for the TO string */
  n = (f.n+1)*(n2+1);
  n = (n+1)&~1;
  m = sqlite3_malloc( n*sizeof(m[0]) + sizeof(a2[0])*n2 );
  if( m==0 ) return -1;            /* Out of memory */
  a2 = (EditDist3To*)&m[n];
  memset(a2, 0, sizeof(a2[0])*n2);
................................................................................
        if( matchTo(p, z2+i2, n2-i2) ){
          updateCost(m, cxd+p->nFrom+szRow*p->nTo, cxd, p->iCost);
        }
      }
    }
  }

#if 0  /* Enable for debugging */
  printf("         ^");
  for(i1=0; i1<f.n; i1++) printf(" %c-%2x", f.z[i1], f.z[i1]&0xff);
  printf("\n   ^:");
  for(i1=0; i1<szRow; i1++){
    int v = m[i1];
    if( v>9999 ) printf(" ****");
    else         printf(" %4d", v);
................................................................................
    pFrom = editDist3FromStringNew(pLang, zA, nA);
    if( pFrom==0 ){
      sqlite3_result_error_nomem(context);
      return;
    }
    dist = editDist3Core(pFrom, zB, nB, pLang, 0);
    editDist3FromStringDelete(pFrom);
    if( dist==(-1) ){
      sqlite3_result_error_nomem(context);
    }else{
      sqlite3_result_int(context, dist);
    }
  } 
}

/*
** Register the editDist3 function with SQLite
*/
static int editDist3Install(sqlite3 *db){
................................................................................

/*
** Return the value of the first UTF-8 character in the string.
*/
static int utf8Read(const unsigned char *z, int n, int *pSize){
  int c, i;

  /* All callers to this routine (in the current implementation)
  ** always have n>0. */
  if( NEVER(n==0) ){
    c = i = 0;
  }else{
    c = z[0];
    i = 1;
    if( c>=0xc0 ){
      c = sqlite3Utf8Trans1[c-0xc0];
      while( i<n && (z[i] & 0xc0)==0x80 ){
................................................................................
** The returned string might contain more characters than the input.
**
** Space to hold the returned string comes from sqlite3_malloc() and
** should be freed by the caller.
*/
static unsigned char *transliterate(const unsigned char *zIn, int nIn){
  unsigned char *zOut = sqlite3_malloc( nIn*4 + 1 );
  int c, sz, nOut;
  if( zOut==0 ) return 0;
  nOut = 0;
  while( nIn>0 ){
    c = utf8Read(zIn, nIn, &sz);
    zIn += sz;
    nIn -= sz;
    if( c<=127 ){
      zOut[nOut++] = c;
    }else{
      int xTop, xBtm, x;
................................................................................
  }
  sqlite3_result_int(context, res);
}

/* End transliterate
******************************************************************************
******************************************************************************


























































































































** Begin spellfix1 virtual table.
*/

/* Maximum length of a phonehash used for querying the shadow table */
#define SPELLFIX_MX_HASH  8

/* Maximum number of hash strings to examine per query */
#define SPELLFIX_MX_RUN   1

typedef struct spellfix1_vtab spellfix1_vtab;
typedef struct spellfix1_cursor spellfix1_cursor;

/* Fuzzy-search virtual table object */
struct spellfix1_vtab {
  sqlite3_vtab base;         /* Base class - must be first */
................................................................................
struct spellfix1_cursor {
  sqlite3_vtab_cursor base;    /* Base class - must be first */
  spellfix1_vtab *pVTab;       /* The table to which this cursor belongs */
  char *zPattern;              /* rhs of MATCH clause */
  int nRow;                    /* Number of rows of content */
  int nAlloc;                  /* Number of allocated rows */
  int iRow;                    /* Current row of content */
  int iLang;                   /* Value of the langid= constraint */
  int iTop;                    /* Value of the top= constraint */
  int iScope;                  /* Value of the scope= constraint */
  int nSearch;                 /* Number of vocabulary items checked */
  sqlite3_stmt *pFullScan;     /* Shadow query for a full table scan */
  struct spellfix1_row {       /* For each row of content */
    sqlite3_int64 iRowid;         /* Rowid for this row */
    char *zWord;                  /* Text for this row */
    int iRank;                    /* Rank for this row */
    int iDistance;                /* Distance from pattern for this row */
    int iScore;                   /* Score for sorting */
    int iMatchlen;                /* Value of matchlen column (or -1) */
................................................................................
  char *zOut;
  int i, j;
  char c;
  while( isspace(zIn[0]) ) zIn++;
  zOut = sqlite3_mprintf("%s", zIn);
  if( zOut==0 ) return 0;
  i = (int)strlen(zOut);
#if 0  /* The parser will never leave spaces at the end */
  while( i>0 && isspace(zOut[i-1]) ){ i--; }
#endif
  zOut[i] = 0;
  c = zOut[0];
  if( c=='\'' || c=='"' ){
    for(i=1, j=0; ALWAYS(zOut[i]); i++){
      zOut[j++] = zOut[i];
      if( zOut[i]==c ){
        if( zOut[i+1]==c ){
          i++;
        }else{
          zOut[j-1] = 0;
          break;
................................................................................
  const char *zModule = argv[0];
  const char *zDbName = argv[1];
  const char *zTableName = argv[2];
  int nDbName;
  int rc = SQLITE_OK;
  int i;







  nDbName = strlen(zDbName);
  pNew = sqlite3_malloc( sizeof(*pNew) + nDbName + 1);
  if( pNew==0 ){
    rc = SQLITE_NOMEM;
  }else{
    memset(pNew, 0, sizeof(*pNew));
    pNew->zDbName = (char*)&pNew[1];
    memcpy(pNew->zDbName, zDbName, nDbName+1);
    pNew->zTableName = sqlite3_mprintf("%s", zTableName);
    pNew->db = db;
    if( pNew->zTableName==0 ){
      rc = SQLITE_NOMEM;
    }else{
      rc = sqlite3_declare_vtab(db, 
           "CREATE TABLE x(word,rank,distance,langid, "
           "score, matchlen, phonehash HIDDEN, "
           "top HIDDEN, scope HIDDEN, srchcnt HIDDEN, "
           "soundslike HIDDEN, command HIDDEN)"
      );
#define SPELLFIX_COL_WORD            0
#define SPELLFIX_COL_RANK            1
#define SPELLFIX_COL_DISTANCE        2
#define SPELLFIX_COL_LANGID          3
#define SPELLFIX_COL_SCORE           4
#define SPELLFIX_COL_MATCHLEN        5
#define SPELLFIX_COL_PHONEHASH       6
#define SPELLFIX_COL_TOP             7
#define SPELLFIX_COL_SCOPE           8
#define SPELLFIX_COL_SRCHCNT         9
#define SPELLFIX_COL_SOUNDSLIKE     10
#define SPELLFIX_COL_COMMAND        11
    }
    if( rc==SQLITE_OK && isCreate ){
      sqlite3_uint64 r;
      spellfix1DbExec(&rc, db,
         "CREATE TABLE IF NOT EXISTS \"%w\".\"%w_vocab\"(\n"
         "  id INTEGER PRIMARY KEY,\n"
         "  rank INT,\n"
         "  langid INT,\n"
         "  word TEXT,\n"
         "  k1 TEXT,\n"
         "  k2 TEXT\n"
         ");\n",
         zDbName, zTableName
      );
      sqlite3_randomness(sizeof(r), &r);
      spellfix1DbExec(&rc, db,
         "CREATE INDEX IF NOT EXISTS \"%w\".\"%w_index_%llx\" "
            "ON \"%w_vocab\"(langid,k2);",
         zDbName, zModule, r, zTableName
      );
    }
    for(i=3; rc==SQLITE_OK && i<argc; i++){
      if( memcmp(argv[i],"edit_cost_table=",16)==0 && pNew->zCostTable==0 ){
        pNew->zCostTable = spellfix1Dequote(&argv[i][16]);
        if( pNew->zCostTable==0 ) rc = SQLITE_NOMEM;
        continue;
      }
      *pzErr = sqlite3_mprintf("bad argument to spellfix1(): \"%s\"", argv[i]);
      rc = SQLITE_ERROR; 

    }
  }

  if( rc && pNew ){
    *ppVTab = 0;
    spellfix1Uninit(0, &pNew->base);
  }else{
    *ppVTab = (sqlite3_vtab *)pNew;
  }
  return rc;
}

/*
** The xConnect and xCreate methods
*/
static int spellfix1Connect(
................................................................................
  int i;
  for(i=0; i<pCur->nRow; i++){
    sqlite3_free(pCur->a[i].zWord);
  }
  pCur->nRow = 0;
  pCur->iRow = 0;
  pCur->nSearch = 0;
  if( pCur->pFullScan ){
    sqlite3_finalize(pCur->pFullScan);
    pCur->pFullScan = 0;
  }
}

/*
** Resize the cursor to hold up to N rows of content
*/
static void spellfix1ResizeCursor(spellfix1_cursor *pCur, int N){
  struct spellfix1_row *aNew;
................................................................................
      iDistTerm = i;
    }
  }
  if( iPlan&1 ){
    int idx = 2;
    pIdxInfo->idxNum = iPlan;
    if( pIdxInfo->nOrderBy==1
     && pIdxInfo->aOrderBy[0].iColumn==SPELLFIX_COL_SCORE
     && pIdxInfo->aOrderBy[0].desc==0
    ){
      pIdxInfo->orderByConsumed = 1;  /* Default order by iScore */
    }
    if( iPlan&2 ){
      pIdxInfo->aConstraintUsage[iLangTerm].argvIndex = idx++;
      pIdxInfo->aConstraintUsage[iLangTerm].omit = 1;
................................................................................
  int iScope = p->iScope;
  spellfix1_cursor *pCur = p->pCur;
  sqlite3_stmt *pStmt = p->pStmt;
  char zHash1[SPELLFIX_MX_HASH];
  char zHash2[SPELLFIX_MX_HASH];
  char *zClass;
  int nClass;
  int rc;

  if( pCur->a==0 || p->rc ) return;   /* Prior memory allocation failure */

  zClass = (char*)phoneticHash((unsigned char*)zQuery, nQuery);
  if( zClass==0 ){
    p->rc = SQLITE_NOMEM;
    return;
  }
  nClass = strlen(zClass);
  if( nClass>SPELLFIX_MX_HASH-2 ){
................................................................................
  }
  memcpy(zHash1, zClass, iScope);
  sqlite3_free(zClass);
  zHash1[iScope] = 0;
  memcpy(zHash2, zHash1, iScope);
  zHash2[iScope] = 'Z';
  zHash2[iScope+1] = 0;
#if SPELLFIX_MX_RUN>1
  for(i=0; i<p->nRun; i++){
    if( strcmp(p->azPrior[i], zHash1)==0 ) return;
  }
#endif
  assert( p->nRun<SPELLFIX_MX_RUN );
  memcpy(p->azPrior[p->nRun++], zHash1, iScope+1);
  if( sqlite3_bind_text(pStmt, 1, zHash1, -1, SQLITE_STATIC)==SQLITE_NOMEM
   || sqlite3_bind_text(pStmt, 2, zHash2, -1, SQLITE_STATIC)==SQLITE_NOMEM
  ){
    p->rc = SQLITE_NOMEM;
    return;
  }
#if SPELLFIX_MX_RUN>1
  for(i=0; i<pCur->nRow; i++){
    if( pCur->a[i].iScore>iWorst ){
      iWorst = pCur->a[i].iScore;
      idxWorst = i;
    }
  }
#endif
  while( sqlite3_step(pStmt)==SQLITE_ROW ){
    int iMatchlen = -1;
    iRank = sqlite3_column_int(pStmt, 2);
    if( p->pMatchStr3 ){
      int nWord = sqlite3_column_bytes(pStmt, 1);
      zWord = (const char*)sqlite3_column_text(pStmt, 1);
      iDist = editDist3Core(p->pMatchStr3, zWord, nWord, p->pLang, &iMatchlen);
    }else{
      zK1 = (const char*)sqlite3_column_text(pStmt, 3);
      if( zK1==0 ) continue;
      iDist = editdist1(p->zPattern, zK1, 0);
    }
    if( iDist<0 ){
      p->rc = SQLITE_NOMEM;
      break;
    }
    pCur->nSearch++;
    iScore = spellfix1Score(iDist,iRank);
    if( p->iMaxDist>=0 ){
      if( iDist>p->iMaxDist ) continue;
      if( pCur->nRow>=pCur->nAlloc-1 ){
        spellfix1ResizeCursor(pCur, pCur->nAlloc*2 + 10);
................................................................................
    }else if( iScore<iWorst ){
      idx = idxWorst;
      sqlite3_free(pCur->a[idx].zWord);
    }else{
      continue;
    }
    pCur->a[idx].zWord = sqlite3_mprintf("%s", sqlite3_column_text(pStmt, 1));
    if( pCur->a[idx].zWord==0 ){
      p->rc = SQLITE_NOMEM;
      break;
    }
    pCur->a[idx].iRowid = sqlite3_column_int64(pStmt, 0);
    pCur->a[idx].iRank = iRank;
    pCur->a[idx].iDistance = iDist;
    pCur->a[idx].iScore = iScore;
    pCur->a[idx].iMatchlen = iMatchlen;
    memcpy(pCur->a[idx].zHash, zHash1, iScope+1);
    if( pCur->nRow<pCur->nAlloc ) pCur->nRow++;
................................................................................
        if( iWorst<iScore ){
          iWorst = iScore;
          idxWorst = i;
        }
      }
    }
  }
  rc = sqlite3_reset(pStmt);
  if( rc ) p->rc = rc;
}

/*
** This version of the xFilter method work if the MATCH term is present
** and we are doing a scan.
*/
static int spellfix1FilterForMatch(
................................................................................
  EditDist3FromString *pMatchStr3 = 0; /* zMatchThis as an editdist string */
  char *zPattern;                    /* Transliteration of zMatchThis */
  int nPattern;                      /* Length of zPattern */
  int iLimit = 20;                   /* Max number of rows of output */
  int iScope = 3;                    /* Use this many characters of zClass */
  int iLang = 0;                     /* Language code */
  char *zSql;                        /* SQL of shadow table query */
  sqlite3_stmt *pStmt = 0;           /* Shadow table query */
  int rc;                            /* Result code */
  int idx = 1;                       /* Next available filter parameter */
  spellfix1_vtab *p = pCur->pVTab;   /* The virtual table that owns pCur */
  MatchQuery x;                      /* For passing info to RunQuery() */

  /* Load the cost table if we have not already done so */
  if( p->zCostTable!=0 && p->pConfig3==0 ){
................................................................................
  spellfix1ResetCursor(pCur);
  spellfix1ResizeCursor(pCur, iLimit);
  zMatchThis = sqlite3_value_text(argv[0]);
  if( zMatchThis==0 ) return SQLITE_OK;
  if( p->pConfig3 ){
    x.pLang = editDist3FindLang(p->pConfig3, iLang);
    pMatchStr3 = editDist3FromStringNew(x.pLang, (const char*)zMatchThis, -1);
    if( pMatchStr3==0 ){
      x.rc = SQLITE_NOMEM;
      goto filter_exit;
    }
  }else{
    x.pLang = 0;
  }
  zPattern = (char*)transliterate(zMatchThis, sqlite3_value_bytes(argv[0]));
  sqlite3_free(pCur->zPattern);
  pCur->zPattern = zPattern;
  if( zPattern==0 ){
    x.rc = SQLITE_NOMEM;
    goto filter_exit;
  }
  nPattern = strlen(zPattern);
  if( zPattern[nPattern-1]=='*' ) nPattern--;
  zSql = sqlite3_mprintf(
     "SELECT id, word, rank, k1"
     "  FROM \"%w\".\"%w_vocab\""
     " WHERE langid=%d AND k2>=?1 AND k2<?2",
     p->zDbName, p->zTableName, iLang
  );
  if( zSql==0 ){
    x.rc = SQLITE_NOMEM;
    pStmt = 0;
    goto filter_exit;
  }
  rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, 0);
  sqlite3_free(zSql);
  pCur->iLang = iLang;
  x.pCur = pCur;
  x.pStmt = pStmt;
  x.zPattern = zPattern;
  x.nPattern = nPattern;
................................................................................
  x.iLang = iLang;
  x.rc = rc;
  x.pConfig3 = p->pConfig3;
  if( x.rc==SQLITE_OK ){
    spellfix1RunQuery(&x, zPattern, nPattern);
  }





















  if( pCur->a ){
    qsort(pCur->a, pCur->nRow, sizeof(pCur->a[0]), spellfix1RowCompare);
    pCur->iTop = iLimit;
    pCur->iScope = iScope;
  }else{
    x.rc = SQLITE_NOMEM;
  }

filter_exit:
  sqlite3_finalize(pStmt);
  editDist3FromStringDelete(pMatchStr3);

  return x.rc;
}

/*
** This version of xFilter handles a full-table scan case
*/
static int spellfix1FilterForFullScan(
  spellfix1_cursor *pCur,
  int idxNum,
  int argc,
  sqlite3_value **argv
){
  int rc;
  char *zSql;
  spellfix1_vtab *pVTab = pCur->pVTab;
  spellfix1ResetCursor(pCur);

  zSql = sqlite3_mprintf(
     "SELECT word, rank, NULL, langid, id FROM \"%w\".\"%w_vocab\"",
     pVTab->zDbName, pVTab->zTableName);
  if( zSql==0 ) return SQLITE_NOMEM;
  rc = sqlite3_prepare_v2(pVTab->db, zSql, -1, &pCur->pFullScan, 0);
  sqlite3_free(zSql);
  pCur->nRow = pCur->iRow = 0;
  if( rc==SQLITE_OK ){
    rc = sqlite3_step(pCur->pFullScan);
    if( rc==SQLITE_ROW ){ pCur->iRow = -1; rc = SQLITE_OK; }
    if( rc==SQLITE_DONE ){ rc = SQLITE_OK; }
  }else{
    pCur->iRow = 0;
  }
  return rc;
}


/*
** Called to "rewind" a cursor back to the beginning so that
** it starts its output over again.  Always called at least once
** prior to any spellfix1Column, spellfix1Rowid, or spellfix1Eof call.
................................................................................


/*
** Advance a cursor to its next row of output
*/
static int spellfix1Next(sqlite3_vtab_cursor *cur){
  spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
  if( pCur->iRow < pCur->nRow ){
    if( pCur->pFullScan ){
      int rc = sqlite3_step(pCur->pFullScan);
      if( rc!=SQLITE_ROW ) pCur->iRow = pCur->nRow;
    }else{
      pCur->iRow++;
    }
  }
  return SQLITE_OK;
}

/*
** Return TRUE if we are at the end-of-file
*/
static int spellfix1Eof(sqlite3_vtab_cursor *cur){
................................................................................
  spellfix1_cursor *pCur = (spellfix1_cursor *)cur;
  return pCur->iRow>=pCur->nRow;
}

/*
** Return columns from the current row.
*/
static int spellfix1Column(
  sqlite3_vtab_cursor *cur,
  sqlite3_context *ctx,
  int i
){
  spellfix1_cursor *pCur = (spellfix1_cursor*)cur;
  if( pCur->pFullScan ){
    if( i<=SPELLFIX_COL_LANGID ){
      sqlite3_result_value(ctx, sqlite3_column_value(pCur->pFullScan, i));
    }else{
      sqlite3_result_null(ctx);
    }
    return SQLITE_OK;
  }
  switch( i ){
    case SPELLFIX_COL_WORD: {
      sqlite3_result_text(ctx, pCur->a[pCur->iRow].zWord, -1, SQLITE_STATIC);
      break;
    }
    case SPELLFIX_COL_RANK: {
      sqlite3_result_int(ctx, pCur->a[pCur->iRow].iRank);
................................................................................
        int nWord = strlen(zWord);

        if( nPattern>0 && pCur->zPattern[nPattern-1]=='*' ){
          char *zTranslit;
          int res;
          zTranslit = (char *)transliterate((unsigned char *)zWord, nWord);
          if( !zTranslit ) return SQLITE_NOMEM;
          res = editdist1(pCur->zPattern, zTranslit, &iMatchlen);
          sqlite3_free(zTranslit);
          if( res<0 ) return SQLITE_NOMEM;
          iMatchlen = translen_to_charlen(zWord, nWord, iMatchlen);
        }else{
          iMatchlen = utf8Charlen(zWord, nWord);
        }
      }
................................................................................
}

/*
** The rowid.
*/
static int spellfix1Rowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
  spellfix1_cursor *pCur = (spellfix1_cursor*)cur;
  if( pCur->pFullScan ){
    *pRowid = sqlite3_column_int64(pCur->pFullScan, 4);
  }else{
    *pRowid = pCur->a[pCur->iRow].iRowid;
  }
  return SQLITE_OK;
}

/*
** The xUpdate() method.
*/
static int spellfix1Update(
................................................................................
             iRank, iLang, zWord, zK1, zK2
      );
      *pRowid = sqlite3_last_insert_rowid(db);
    }else{
      rowid = sqlite3_value_int64(argv[0]);
      newRowid = *pRowid = sqlite3_value_int64(argv[1]);
      spellfix1DbExec(&rc, db,
             "UPDATE \"%w\".\"%w_vocab\" SET id=%lld, rank=%d, langid=%d,"
             " word=%Q, k1=%Q, k2=%Q WHERE id=%lld",
             p->zDbName, p->zTableName, newRowid, iRank, iLang,
             zWord, zK1, zK2, rowid
      );
    }
    sqlite3_free(zK1);
    sqlite3_free(zK2);
  }
................................................................................
  spellfix1DbExec(&rc, db, 
     "ALTER TABLE \"%w\".\"%w_vocab\" RENAME TO \"%w_vocab\"",
     p->zDbName, p->zTableName, zNewName
  );
  if( rc==SQLITE_OK ){
    sqlite3_free(p->zTableName);
    p->zTableName = zNewName;
  }else{
    sqlite3_free(zNewName);
  }
  return rc;
}


/*
** A virtual table module that provides fuzzy search.
................................................................................
static int spellfix1Register(sqlite3 *db){
  int nErr = 0;
  int i;
  nErr += sqlite3_create_function(db, "spellfix1_translit", 1, SQLITE_UTF8, 0,
                                  transliterateSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "spellfix1_editdist", 2, SQLITE_UTF8, 0,
                                  editdistSqlFunc, 0, 0);


  nErr += sqlite3_create_function(db, "spellfix1_phonehash", 1, SQLITE_UTF8, 0,
                                  phoneticHashSqlFunc, 0, 0);
  nErr += sqlite3_create_function(db, "spellfix1_scriptcode", 1, SQLITE_UTF8, 0,
                                  scriptCodeSqlFunc, 0, 0);




  nErr += sqlite3_create_module(db, "spellfix1", &spellfix1Module, 0);
  nErr += editDist3Install(db);

  /* Verify sanity of the translit[] table */
  for(i=0; i<sizeof(translit)/sizeof(translit[0])-1; i++){
    assert( translit[i].cFrom<translit[i+1].cFrom );
  }

){
  int rc = SQLITE_OK;
  TestvfsFd *pFd = tvfsGetFd(pFile);
  Testvfs *p = (Testvfs *)pFd->pVfs->pAppData;

  if( p->pScript && p->mask&TESTVFS_WRITE_MASK ){
    tvfsExecTcl(p, "xWrite", 
        Tcl_NewStringObj(pFd->zFilename, -1), pFd->pShmId, 0

    );
    tvfsResultCode(p, &rc);
  }

  if( rc==SQLITE_OK && tvfsInjectFullerr(p) ){
    rc = SQLITE_FULL;
  }

){
  int rc = SQLITE_OK;
  TestvfsFd *pFd = tvfsGetFd(pFile);
  Testvfs *p = (Testvfs *)pFd->pVfs->pAppData;

  if( p->pScript && p->mask&TESTVFS_WRITE_MASK ){
    tvfsExecTcl(p, "xWrite", 
        Tcl_NewStringObj(pFd->zFilename, -1), pFd->pShmId, 
        Tcl_NewWideIntObj(iOfst)
    );
    tvfsResultCode(p, &rc);
  }

  if( rc==SQLITE_OK && tvfsInjectFullerr(p) ){
    rc = SQLITE_FULL;
  }

  int p2;
  int iDb;
  int wrFlag;
  Btree *pX;
  VdbeCursor *pCur;
  Db *pDb;




  if( p->expired ){
    rc = SQLITE_ABORT;
    break;
  }

  nField = 0;
  pKeyInfo = 0;
................................................................................
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    if( pDb->pSchema->file_format < p->minWriteFileFormat ){
      p->minWriteFileFormat = pDb->pSchema->file_format;
    }
  }else{
    wrFlag = 0;
  }
  if( pOp->p5 ){
    assert( p2>0 );
    assert( p2<=p->nMem );
    pIn2 = &aMem[p2];
    assert( memIsValid(pIn2) );
    assert( (pIn2->flags & MEM_Int)!=0 );
    sqlite3VdbeMemIntegerify(pIn2);
    p2 = (int)pIn2->u.i;
................................................................................
  assert( pOp->p1>=0 );
  pCur = allocateCursor(p, pOp->p1, nField, iDb, 1);
  if( pCur==0 ) goto no_mem;
  pCur->nullRow = 1;
  pCur->isOrdered = 1;
  rc = sqlite3BtreeCursor(pX, p2, wrFlag, pKeyInfo, pCur->pCursor);
  pCur->pKeyInfo = pKeyInfo;



  /* Since it performs no memory allocation or IO, the only value that
  ** sqlite3BtreeCursor() may return is SQLITE_OK. */
  assert( rc==SQLITE_OK );

  /* Set the VdbeCursor.isTable and isIndex variables. Previous versions of
  ** SQLite used to check if the root-page flags were sane at this point

  int p2;
  int iDb;
  int wrFlag;
  Btree *pX;
  VdbeCursor *pCur;
  Db *pDb;

  assert( (pOp->p5&(OPFLAG_P2ISREG|OPFLAG_BULKCSR))==pOp->p5 );
  assert( pOp->opcode==OP_OpenWrite || pOp->p5==0 );

  if( p->expired ){
    rc = SQLITE_ABORT;
    break;
  }

  nField = 0;
  pKeyInfo = 0;
................................................................................
    assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
    if( pDb->pSchema->file_format < p->minWriteFileFormat ){
      p->minWriteFileFormat = pDb->pSchema->file_format;
    }
  }else{
    wrFlag = 0;
  }
  if( pOp->p5 & OPFLAG_P2ISREG ){
    assert( p2>0 );
    assert( p2<=p->nMem );
    pIn2 = &aMem[p2];
    assert( memIsValid(pIn2) );
    assert( (pIn2->flags & MEM_Int)!=0 );
    sqlite3VdbeMemIntegerify(pIn2);
    p2 = (int)pIn2->u.i;
................................................................................
  assert( pOp->p1>=0 );
  pCur = allocateCursor(p, pOp->p1, nField, iDb, 1);
  if( pCur==0 ) goto no_mem;
  pCur->nullRow = 1;
  pCur->isOrdered = 1;
  rc = sqlite3BtreeCursor(pX, p2, wrFlag, pKeyInfo, pCur->pCursor);
  pCur->pKeyInfo = pKeyInfo;
  assert( OPFLAG_BULKCSR==BTREE_BULKLOAD );
  sqlite3BtreeCursorHints(pCur->pCursor, (pOp->p5 & OPFLAG_BULKCSR));

  /* Since it performs no memory allocation or IO, the only value that
  ** sqlite3BtreeCursor() may return is SQLITE_OK. */
  assert( rc==SQLITE_OK );

  /* Set the VdbeCursor.isTable and isIndex variables. Previous versions of
  ** SQLite used to check if the root-page flags were sane at this point

# define sqlite3VdbeSorterRowkey(Y,Z)    SQLITE_OK
# define sqlite3VdbeSorterRewind(X,Y,Z)  SQLITE_OK
# define sqlite3VdbeSorterNext(X,Y,Z)    SQLITE_OK
# define sqlite3VdbeSorterCompare(X,Y,Z) SQLITE_OK
#else
int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
int sqlite3VdbeSorterRowkey(VdbeCursor *, Mem *);
int sqlite3VdbeSorterNext(sqlite3 *, VdbeCursor *, int *);
int sqlite3VdbeSorterRewind(sqlite3 *, VdbeCursor *, int *);
int sqlite3VdbeSorterWrite(sqlite3 *, VdbeCursor *, Mem *);
int sqlite3VdbeSorterCompare(VdbeCursor *, Mem *, int *);
#endif

#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
  void sqlite3VdbeEnter(Vdbe*);
  void sqlite3VdbeLeave(Vdbe*);
#else
# define sqlite3VdbeEnter(X)

# define sqlite3VdbeSorterRowkey(Y,Z)    SQLITE_OK
# define sqlite3VdbeSorterRewind(X,Y,Z)  SQLITE_OK
# define sqlite3VdbeSorterNext(X,Y,Z)    SQLITE_OK
# define sqlite3VdbeSorterCompare(X,Y,Z) SQLITE_OK
#else
int sqlite3VdbeSorterInit(sqlite3 *, VdbeCursor *);
void sqlite3VdbeSorterClose(sqlite3 *, VdbeCursor *);
int sqlite3VdbeSorterRowkey(const VdbeCursor *, Mem *);
int sqlite3VdbeSorterNext(sqlite3 *, const VdbeCursor *, int *);
int sqlite3VdbeSorterRewind(sqlite3 *, const VdbeCursor *, int *);
int sqlite3VdbeSorterWrite(sqlite3 *, const VdbeCursor *, Mem *);
int sqlite3VdbeSorterCompare(const VdbeCursor *, Mem *, int *);
#endif

#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE>0
  void sqlite3VdbeEnter(Vdbe*);
  void sqlite3VdbeLeave(Vdbe*);
#else
# define sqlite3VdbeEnter(X)

#include "sqliteInt.h"
#include "vdbeInt.h"

#ifndef SQLITE_OMIT_MERGE_SORT

typedef struct VdbeSorterIter VdbeSorterIter;
typedef struct SorterRecord SorterRecord;


/*
** NOTES ON DATA STRUCTURE USED FOR N-WAY MERGES:
**
** As keys are added to the sorter, they are written to disk in a series
** of sorted packed-memory-arrays (PMAs). The size of each PMA is roughly
** the same as the cache-size allowed for temporary databases. In order
................................................................................
  i64 iReadOff;                   /* Current read offset */
  i64 iEof;                       /* 1 byte past EOF for this iterator */
  int nAlloc;                     /* Bytes of space at aAlloc */
  int nKey;                       /* Number of bytes in key */
  sqlite3_file *pFile;            /* File iterator is reading from */
  u8 *aAlloc;                     /* Allocated space */
  u8 *aKey;                       /* Pointer to current key */


















};

/*
** A structure to store a single record. All in-memory records are connected
** together into a linked list headed at VdbeSorter.pRecord using the 
** SorterRecord.pNext pointer.
*/
................................................................................

/*
** Free all memory belonging to the VdbeSorterIter object passed as the second
** argument. All structure fields are set to zero before returning.
*/
static void vdbeSorterIterZero(sqlite3 *db, VdbeSorterIter *pIter){
  sqlite3DbFree(db, pIter->aAlloc);

  memset(pIter, 0, sizeof(VdbeSorterIter));
}

/*

















































































































** Advance iterator pIter to the next key in its PMA. Return SQLITE_OK if
** no error occurs, or an SQLite error code if one does.
*/
static int vdbeSorterIterNext(
  sqlite3 *db,                    /* Database handle (for sqlite3DbMalloc() ) */
  VdbeSorterIter *pIter           /* Iterator to advance */
){
  int rc;                         /* Return Code */
  int nRead;                      /* Number of bytes read */
  int nRec = 0;                   /* Size of record in bytes */
  int iOff = 0;                   /* Size of serialized size varint in bytes */

  assert( pIter->iEof>=pIter->iReadOff );
  if( pIter->iEof-pIter->iReadOff>5 ){
    nRead = 5;
  }else{
    nRead = (int)(pIter->iEof - pIter->iReadOff);
  }
  if( nRead<=0 ){
    /* This is an EOF condition */
    vdbeSorterIterZero(db, pIter);
    return SQLITE_OK;
  }

  rc = sqlite3OsRead(pIter->pFile, pIter->aAlloc, nRead, pIter->iReadOff);
  if( rc==SQLITE_OK ){
    iOff = getVarint32(pIter->aAlloc, nRec);
    if( (iOff+nRec)>nRead ){
      int nRead2;                   /* Number of extra bytes to read */
      if( (iOff+nRec)>pIter->nAlloc ){
        int nNew = pIter->nAlloc*2;
        while( (iOff+nRec)>nNew ) nNew = nNew*2;
        pIter->aAlloc = sqlite3DbReallocOrFree(db, pIter->aAlloc, nNew);
        if( !pIter->aAlloc ) return SQLITE_NOMEM;
        pIter->nAlloc = nNew;
      }
  
      nRead2 = iOff + nRec - nRead;
      rc = sqlite3OsRead(
          pIter->pFile, &pIter->aAlloc[nRead], nRead2, pIter->iReadOff+nRead
      );
    }
  }

  assert( rc!=SQLITE_OK || nRec>0 );
  pIter->iReadOff += iOff+nRec;
  pIter->nKey = nRec;
  pIter->aKey = &pIter->aAlloc[iOff];
  return rc;
}

/*
** Write a single varint, value iVal, to file-descriptor pFile. Return
** SQLITE_OK if successful, or an SQLite error code if some error occurs.
**
** The value of *piOffset when this function is called is used as the byte
** offset in file pFile to write to. Before returning, *piOffset is 
** incremented by the number of bytes written.
*/
static int vdbeSorterWriteVarint(
  sqlite3_file *pFile,            /* File to write to */
  i64 iVal,                       /* Value to write as a varint */
  i64 *piOffset                   /* IN/OUT: Write offset in file pFile */
){
  u8 aVarint[9];                  /* Buffer large enough for a varint */
  int nVarint;                    /* Number of used bytes in varint */
  int rc;                         /* Result of write() call */

  nVarint = sqlite3PutVarint(aVarint, iVal);
  rc = sqlite3OsWrite(pFile, aVarint, nVarint, *piOffset);
  *piOffset += nVarint;

  return rc;
}

/*
** Read a single varint from file-descriptor pFile. Return SQLITE_OK if
** successful, or an SQLite error code if some error occurs.
**
** The value of *piOffset when this function is called is used as the
** byte offset in file pFile from whence to read the varint. If successful
** (i.e. if no IO error occurs), then *piOffset is set to the offset of
** the first byte past the end of the varint before returning. *piVal is
** set to the integer value read. If an error occurs, the final values of
** both *piOffset and *piVal are undefined.
*/
static int vdbeSorterReadVarint(
  sqlite3_file *pFile,            /* File to read from */
  i64 *piOffset,                  /* IN/OUT: Read offset in pFile */
  i64 *piVal                      /* OUT: Value read from file */
){
  u8 aVarint[9];                  /* Buffer large enough for a varint */
  i64 iOff = *piOffset;           /* Offset in file to read from */
  int rc;                         /* Return code */

  rc = sqlite3OsRead(pFile, aVarint, 9, iOff);
  if( rc==SQLITE_OK ){
    *piOffset += getVarint(aVarint, (u64 *)piVal);

  }

  return rc;
}

/*
** Initialize iterator pIter to scan through the PMA stored in file pFile
** starting at offset iStart and ending at offset iEof-1. This function 
** leaves the iterator pointing to the first key in the PMA (or EOF if the 
** PMA is empty).
*/
static int vdbeSorterIterInit(
  sqlite3 *db,                    /* Database handle */
  VdbeSorter *pSorter,            /* Sorter object */
  i64 iStart,                     /* Start offset in pFile */
  VdbeSorterIter *pIter,          /* Iterator to populate */
  i64 *pnByte                     /* IN/OUT: Increment this value by PMA size */
){

  int rc;



  assert( pSorter->iWriteOff>iStart );
  assert( pIter->aAlloc==0 );

  pIter->pFile = pSorter->pTemp1;
  pIter->iReadOff = iStart;
  pIter->nAlloc = 128;
  pIter->aAlloc = (u8 *)sqlite3DbMallocRaw(db, pIter->nAlloc);



  if( !pIter->aAlloc ){
    rc = SQLITE_NOMEM;
  }else{















    i64 nByte;                         /* Total size of PMA in bytes */
    rc = vdbeSorterReadVarint(pSorter->pTemp1, &pIter->iReadOff, &nByte);
    *pnByte += nByte;


    pIter->iEof = pIter->iReadOff + nByte;

  }


  if( rc==SQLITE_OK ){
    rc = vdbeSorterIterNext(db, pIter);
  }
  return rc;
}


................................................................................
** is true and key1 contains even a single NULL value, it is considered to
** be less than key2. Even if key2 also contains NULL values.
**
** If pKey2 is passed a NULL pointer, then it is assumed that the pCsr->aSpace
** has been allocated and contains an unpacked record that is used as key2.
*/
static void vdbeSorterCompare(
  VdbeCursor *pCsr,               /* Cursor object (for pKeyInfo) */
  int bOmitRowid,                 /* Ignore rowid field at end of keys */
  void *pKey1, int nKey1,         /* Left side of comparison */
  void *pKey2, int nKey2,         /* Right side of comparison */
  int *pRes                       /* OUT: Result of comparison */
){
  KeyInfo *pKeyInfo = pCsr->pKeyInfo;
  VdbeSorter *pSorter = pCsr->pSorter;
  UnpackedRecord *r2 = pSorter->pUnpacked;
  int i;

................................................................................
}

/*
** This function is called to compare two iterator keys when merging 
** multiple b-tree segments. Parameter iOut is the index of the aTree[] 
** value to recalculate.
*/
static int vdbeSorterDoCompare(VdbeCursor *pCsr, int iOut){
  VdbeSorter *pSorter = pCsr->pSorter;
  int i1;
  int i2;
  int iRes;
  VdbeSorterIter *p1;
  VdbeSorterIter *p2;

................................................................................
}

/*
** Merge the two sorted lists p1 and p2 into a single list.
** Set *ppOut to the head of the new list.
*/
static void vdbeSorterMerge(
  VdbeCursor *pCsr,               /* For pKeyInfo */
  SorterRecord *p1,               /* First list to merge */
  SorterRecord *p2,               /* Second list to merge */
  SorterRecord **ppOut            /* OUT: Head of merged list */
){
  SorterRecord *pFinal = 0;
  SorterRecord **pp = &pFinal;
  void *pVal2 = p2 ? p2->pVal : 0;
................................................................................
}

/*
** Sort the linked list of records headed at pCsr->pRecord. Return SQLITE_OK
** if successful, or an SQLite error code (i.e. SQLITE_NOMEM) if an error
** occurs.
*/
static int vdbeSorterSort(VdbeCursor *pCsr){
  int i;
  SorterRecord **aSlot;
  SorterRecord *p;
  VdbeSorter *pSorter = pCsr->pSorter;

  aSlot = (SorterRecord **)sqlite3MallocZero(64 * sizeof(SorterRecord *));
  if( !aSlot ){
................................................................................
  }
  pSorter->pRecord = p;

  sqlite3_free(aSlot);
  return SQLITE_OK;
}























































































/*
** Write the current contents of the in-memory linked-list to a PMA. Return
** SQLITE_OK if successful, or an SQLite error code otherwise.
**
** The format of a PMA is:
**
................................................................................
**     * A varint. This varint contains the total number of bytes of content
**       in the PMA (not including the varint itself).
**
**     * One or more records packed end-to-end in order of ascending keys. 
**       Each record consists of a varint followed by a blob of data (the 
**       key). The varint is the number of bytes in the blob of data.
*/
static int vdbeSorterListToPMA(sqlite3 *db, VdbeCursor *pCsr){
  int rc = SQLITE_OK;             /* Return code */
  VdbeSorter *pSorter = pCsr->pSorter;




  if( pSorter->nInMemory==0 ){
    assert( pSorter->pRecord==0 );
    return rc;
  }

  rc = vdbeSorterSort(pCsr);
................................................................................
    rc = vdbeSorterOpenTempFile(db, &pSorter->pTemp1);
    assert( rc!=SQLITE_OK || pSorter->pTemp1 );
    assert( pSorter->iWriteOff==0 );
    assert( pSorter->nPMA==0 );
  }

  if( rc==SQLITE_OK ){
    i64 iOff = pSorter->iWriteOff;
    SorterRecord *p;
    SorterRecord *pNext = 0;
    static const char eightZeros[8] = { 0, 0, 0, 0, 0, 0, 0, 0 };


    pSorter->nPMA++;
    rc = vdbeSorterWriteVarint(pSorter->pTemp1, pSorter->nInMemory, &iOff);

    for(p=pSorter->pRecord; rc==SQLITE_OK && p; p=pNext){
      pNext = p->pNext;

      rc = vdbeSorterWriteVarint(pSorter->pTemp1, p->nVal, &iOff);

      if( rc==SQLITE_OK ){
        rc = sqlite3OsWrite(pSorter->pTemp1, p->pVal, p->nVal, iOff);
        iOff += p->nVal;
      }

      sqlite3DbFree(db, p);
    }

    /* This assert verifies that unless an error has occurred, the size of 
    ** the PMA on disk is the same as the expected size stored in
    ** pSorter->nInMemory. */ 
    assert( rc!=SQLITE_OK || pSorter->nInMemory==(
          iOff-pSorter->iWriteOff-sqlite3VarintLen(pSorter->nInMemory)
    ));

    pSorter->iWriteOff = iOff;
    if( rc==SQLITE_OK ){
      /* Terminate each file with 8 extra bytes so that from any offset
      ** in the file we can always read 9 bytes without a SHORT_READ error */
      rc = sqlite3OsWrite(pSorter->pTemp1, eightZeros, 8, iOff);
    }
    pSorter->pRecord = p;

  }

  return rc;
}

/*
** Add a record to the sorter.
*/
int sqlite3VdbeSorterWrite(
  sqlite3 *db,                    /* Database handle */
  VdbeCursor *pCsr,               /* Sorter cursor */
  Mem *pVal                       /* Memory cell containing record */
){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc = SQLITE_OK;             /* Return Code */
  SorterRecord *pNew;             /* New list element */

  assert( pSorter );
................................................................................
  **   * The total memory allocated for the in-memory list is greater 
  **     than (page-size * 10) and sqlite3HeapNearlyFull() returns true.
  */
  if( rc==SQLITE_OK && pSorter->mxPmaSize>0 && (
        (pSorter->nInMemory>pSorter->mxPmaSize)
     || (pSorter->nInMemory>pSorter->mnPmaSize && sqlite3HeapNearlyFull())
  )){





    rc = vdbeSorterListToPMA(db, pCsr);
    pSorter->nInMemory = 0;

  }

  return rc;
}

/*
** Helper function for sqlite3VdbeSorterRewind(). 
*/
static int vdbeSorterInitMerge(
  sqlite3 *db,                    /* Database handle */
  VdbeCursor *pCsr,               /* Cursor handle for this sorter */
  i64 *pnByte                     /* Sum of bytes in all opened PMAs */
){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc = SQLITE_OK;             /* Return code */
  int i;                          /* Used to iterator through aIter[] */
  i64 nByte = 0;                  /* Total bytes in all opened PMAs */

................................................................................
  return rc;
}

/*
** Once the sorter has been populated, this function is called to prepare
** for iterating through its contents in sorted order.
*/
int sqlite3VdbeSorterRewind(sqlite3 *db, VdbeCursor *pCsr, int *pbEof){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc;                         /* Return code */
  sqlite3_file *pTemp2 = 0;       /* Second temp file to use */
  i64 iWrite2 = 0;                /* Write offset for pTemp2 */
  int nIter;                      /* Number of iterators used */
  int nByte;                      /* Bytes of space required for aIter/aTree */
  int N = 2;                      /* Power of 2 >= nIter */
................................................................................
  ** from the in-memory list.  */
  if( pSorter->nPMA==0 ){
    *pbEof = !pSorter->pRecord;
    assert( pSorter->aTree==0 );
    return vdbeSorterSort(pCsr);
  }

  /* Write the current b-tree to a PMA. Close the b-tree cursor. */
  rc = vdbeSorterListToPMA(db, pCsr);
  if( rc!=SQLITE_OK ) return rc;

  /* Allocate space for aIter[] and aTree[]. */
  nIter = pSorter->nPMA;
  if( nIter>SORTER_MAX_MERGE_COUNT ) nIter = SORTER_MAX_MERGE_COUNT;
  assert( nIter>0 );
................................................................................
  do {
    int iNew;                     /* Index of new, merged, PMA */

    for(iNew=0; 
        rc==SQLITE_OK && iNew*SORTER_MAX_MERGE_COUNT<pSorter->nPMA; 
        iNew++
    ){


      i64 nWrite;                 /* Number of bytes in new PMA */



      /* If there are SORTER_MAX_MERGE_COUNT or less PMAs in file pTemp1,
      ** initialize an iterator for each of them and break out of the loop.
      ** These iterators will be incrementally merged as the VDBE layer calls
      ** sqlite3VdbeSorterNext().
      **
      ** Otherwise, if pTemp1 contains more than SORTER_MAX_MERGE_COUNT PMAs,
................................................................................

      /* Open the second temp file, if it is not already open. */
      if( pTemp2==0 ){
        assert( iWrite2==0 );
        rc = vdbeSorterOpenTempFile(db, &pTemp2);
      }

      if( rc==SQLITE_OK ){
        rc = vdbeSorterWriteVarint(pTemp2, nWrite, &iWrite2);
      }

      if( rc==SQLITE_OK ){
        int bEof = 0;


        while( rc==SQLITE_OK && bEof==0 ){
          int nToWrite;
          VdbeSorterIter *pIter = &pSorter->aIter[ pSorter->aTree[1] ];
          assert( pIter->pFile );
          nToWrite = pIter->nKey + sqlite3VarintLen(pIter->nKey);
          rc = sqlite3OsWrite(pTemp2, pIter->aAlloc, nToWrite, iWrite2);
          iWrite2 += nToWrite;
          if( rc==SQLITE_OK ){



            rc = sqlite3VdbeSorterNext(db, pCsr, &bEof);
          }
        }


      }
    }

    if( pSorter->nPMA<=SORTER_MAX_MERGE_COUNT ){
      break;
    }else{
      sqlite3_file *pTmp = pSorter->pTemp1;
................................................................................
  *pbEof = (pSorter->aIter[pSorter->aTree[1]].pFile==0);
  return rc;
}

/*
** Advance to the next element in the sorter.
*/
int sqlite3VdbeSorterNext(sqlite3 *db, VdbeCursor *pCsr, int *pbEof){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc;                         /* Return code */

  if( pSorter->aTree ){
    int iPrev = pSorter->aTree[1];/* Index of iterator to advance */
    int i;                        /* Index of aTree[] to recalculate */

................................................................................
}

/*
** Return a pointer to a buffer owned by the sorter that contains the 
** current key.
*/
static void *vdbeSorterRowkey(
  VdbeSorter *pSorter,            /* Sorter object */
  int *pnKey                      /* OUT: Size of current key in bytes */
){
  void *pKey;
  if( pSorter->aTree ){
    VdbeSorterIter *pIter;
    pIter = &pSorter->aIter[ pSorter->aTree[1] ];
    *pnKey = pIter->nKey;
................................................................................
  }
  return pKey;
}

/*
** Copy the current sorter key into the memory cell pOut.
*/
int sqlite3VdbeSorterRowkey(VdbeCursor *pCsr, Mem *pOut){
  VdbeSorter *pSorter = pCsr->pSorter;
  void *pKey; int nKey;           /* Sorter key to copy into pOut */

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  if( sqlite3VdbeMemGrow(pOut, nKey, 0) ){
    return SQLITE_NOMEM;
  }
................................................................................
**
** If an error occurs, return an SQLite error code (i.e. SQLITE_NOMEM).
** Otherwise, set *pRes to a negative, zero or positive value if the
** key in pVal is smaller than, equal to or larger than the current sorter
** key.
*/
int sqlite3VdbeSorterCompare(
  VdbeCursor *pCsr,               /* Sorter cursor */
  Mem *pVal,                      /* Value to compare to current sorter key */
  int *pRes                       /* OUT: Result of comparison */
){
  VdbeSorter *pSorter = pCsr->pSorter;
  void *pKey; int nKey;           /* Sorter key to compare pVal with */

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  vdbeSorterCompare(pCsr, 1, pVal->z, pVal->n, pKey, nKey, pRes);
  return SQLITE_OK;
}

#endif /* #ifndef SQLITE_OMIT_MERGE_SORT */

#include "sqliteInt.h"
#include "vdbeInt.h"

#ifndef SQLITE_OMIT_MERGE_SORT

typedef struct VdbeSorterIter VdbeSorterIter;
typedef struct SorterRecord SorterRecord;
typedef struct FileWriter FileWriter;

/*
** NOTES ON DATA STRUCTURE USED FOR N-WAY MERGES:
**
** As keys are added to the sorter, they are written to disk in a series
** of sorted packed-memory-arrays (PMAs). The size of each PMA is roughly
** the same as the cache-size allowed for temporary databases. In order
................................................................................
  i64 iReadOff;                   /* Current read offset */
  i64 iEof;                       /* 1 byte past EOF for this iterator */
  int nAlloc;                     /* Bytes of space at aAlloc */
  int nKey;                       /* Number of bytes in key */
  sqlite3_file *pFile;            /* File iterator is reading from */
  u8 *aAlloc;                     /* Allocated space */
  u8 *aKey;                       /* Pointer to current key */
  u8 *aBuffer;                    /* Current read buffer */
  int nBuffer;                    /* Size of read buffer in bytes */
};

/*
** An instance of this structure is used to organize the stream of records
** being written to files by the merge-sort code into aligned, page-sized
** blocks.  Doing all I/O in aligned page-sized blocks helps I/O to go
** faster on many operating systems.
*/
struct FileWriter {
  int eFWErr;                     /* Non-zero if in an error state */
  u8 *aBuffer;                    /* Pointer to write buffer */
  int nBuffer;                    /* Size of write buffer in bytes */
  int iBufStart;                  /* First byte of buffer to write */
  int iBufEnd;                    /* Last byte of buffer to write */
  i64 iWriteOff;                  /* Offset of start of buffer in file */
  sqlite3_file *pFile;            /* File to write to */
};

/*
** A structure to store a single record. All in-memory records are connected
** together into a linked list headed at VdbeSorter.pRecord using the 
** SorterRecord.pNext pointer.
*/
................................................................................

/*
** Free all memory belonging to the VdbeSorterIter object passed as the second
** argument. All structure fields are set to zero before returning.
*/
static void vdbeSorterIterZero(sqlite3 *db, VdbeSorterIter *pIter){
  sqlite3DbFree(db, pIter->aAlloc);
  sqlite3DbFree(db, pIter->aBuffer);
  memset(pIter, 0, sizeof(VdbeSorterIter));
}

/*
** Read nByte bytes of data from the stream of data iterated by object p.
** If successful, set *ppOut to point to a buffer containing the data
** and return SQLITE_OK. Otherwise, if an error occurs, return an SQLite
** error code.
**
** The buffer indicated by *ppOut may only be considered valid until the
** next call to this function.
*/
static int vdbeSorterIterRead(
  sqlite3 *db,                    /* Database handle (for malloc) */
  VdbeSorterIter *p,              /* Iterator */
  int nByte,                      /* Bytes of data to read */
  u8 **ppOut                      /* OUT: Pointer to buffer containing data */
){
  int iBuf;                       /* Offset within buffer to read from */
  int nAvail;                     /* Bytes of data available in buffer */
  assert( p->aBuffer );

  /* If there is no more data to be read from the buffer, read the next 
  ** p->nBuffer bytes of data from the file into it. Or, if there are less
  ** than p->nBuffer bytes remaining in the PMA, read all remaining data.  */
  iBuf = p->iReadOff % p->nBuffer;
  if( iBuf==0 ){
    int nRead;                    /* Bytes to read from disk */
    int rc;                       /* sqlite3OsRead() return code */

    /* Determine how many bytes of data to read. */
    nRead = (int)(p->iEof - p->iReadOff);
    if( nRead>p->nBuffer ) nRead = p->nBuffer;
    assert( nRead>0 );

    /* Read data from the file. Return early if an error occurs. */
    rc = sqlite3OsRead(p->pFile, p->aBuffer, nRead, p->iReadOff);
    assert( rc!=SQLITE_IOERR_SHORT_READ );
    if( rc!=SQLITE_OK ) return rc;
  }
  nAvail = p->nBuffer - iBuf; 

  if( nByte<=nAvail ){
    /* The requested data is available in the in-memory buffer. In this
    ** case there is no need to make a copy of the data, just return a 
    ** pointer into the buffer to the caller.  */
    *ppOut = &p->aBuffer[iBuf];
    p->iReadOff += nByte;
  }else{
    /* The requested data is not all available in the in-memory buffer.
    ** In this case, allocate space at p->aAlloc[] to copy the requested
    ** range into. Then return a copy of pointer p->aAlloc to the caller.  */
    int nRem;                     /* Bytes remaining to copy */

    /* Extend the p->aAlloc[] allocation if required. */
    if( p->nAlloc<nByte ){
      int nNew = p->nAlloc*2;
      while( nByte>nNew ) nNew = nNew*2;
      p->aAlloc = sqlite3DbReallocOrFree(db, p->aAlloc, nNew);
      if( !p->aAlloc ) return SQLITE_NOMEM;
      p->nAlloc = nNew;
    }

    /* Copy as much data as is available in the buffer into the start of
    ** p->aAlloc[].  */
    memcpy(p->aAlloc, &p->aBuffer[iBuf], nAvail);
    p->iReadOff += nAvail;
    nRem = nByte - nAvail;

    /* The following loop copies up to p->nBuffer bytes per iteration into
    ** the p->aAlloc[] buffer.  */
    while( nRem>0 ){
      int rc;                     /* vdbeSorterIterRead() return code */
      int nCopy;                  /* Number of bytes to copy */
      u8 *aNext;                  /* Pointer to buffer to copy data from */

      nCopy = nRem;
      if( nRem>p->nBuffer ) nCopy = p->nBuffer;
      rc = vdbeSorterIterRead(db, p, nCopy, &aNext);
      if( rc!=SQLITE_OK ) return rc;
      assert( aNext!=p->aAlloc );
      memcpy(&p->aAlloc[nByte - nRem], aNext, nCopy);
      nRem -= nCopy;
    }

    *ppOut = p->aAlloc;
  }

  return SQLITE_OK;
}

/*
** Read a varint from the stream of data accessed by p. Set *pnOut to
** the value read.
*/
static int vdbeSorterIterVarint(sqlite3 *db, VdbeSorterIter *p, u64 *pnOut){
  int iBuf;

  iBuf = p->iReadOff % p->nBuffer;
  if( iBuf && (p->nBuffer-iBuf)>=9 ){
    p->iReadOff += sqlite3GetVarint(&p->aBuffer[iBuf], pnOut);
  }else{
    u8 aVarint[16], *a;
    int i = 0, rc;
    do{
      rc = vdbeSorterIterRead(db, p, 1, &a);
      if( rc ) return rc;
      aVarint[(i++)&0xf] = a[0];
    }while( (a[0]&0x80)!=0 );
    sqlite3GetVarint(aVarint, pnOut);
  }

  return SQLITE_OK;
}


/*
** Advance iterator pIter to the next key in its PMA. Return SQLITE_OK if
** no error occurs, or an SQLite error code if one does.
*/
static int vdbeSorterIterNext(
  sqlite3 *db,                    /* Database handle (for sqlite3DbMalloc() ) */
  VdbeSorterIter *pIter           /* Iterator to advance */
){
  int rc;                         /* Return Code */

  u64 nRec = 0;                   /* Size of record in bytes */



  if( pIter->iReadOff>=pIter->iEof ){





    /* This is an EOF condition */
    vdbeSorterIterZero(db, pIter);
    return SQLITE_OK;
  }

  rc = vdbeSorterIterVarint(db, pIter, &nRec);
  if( rc==SQLITE_OK ){




















    pIter->nKey = (int)nRec;



















































    rc = vdbeSorterIterRead(db, pIter, (int)nRec, &pIter->aKey);
  }

  return rc;
}

/*
** Initialize iterator pIter to scan through the PMA stored in file pFile
** starting at offset iStart and ending at offset iEof-1. This function 
** leaves the iterator pointing to the first key in the PMA (or EOF if the 
** PMA is empty).
*/
static int vdbeSorterIterInit(
  sqlite3 *db,                    /* Database handle */
  const VdbeSorter *pSorter,      /* Sorter object */
  i64 iStart,                     /* Start offset in pFile */
  VdbeSorterIter *pIter,          /* Iterator to populate */
  i64 *pnByte                     /* IN/OUT: Increment this value by PMA size */
){
  int rc = SQLITE_OK;
  int nBuf;

  nBuf = sqlite3BtreeGetPageSize(db->aDb[0].pBt);

  assert( pSorter->iWriteOff>iStart );
  assert( pIter->aAlloc==0 );
  assert( pIter->aBuffer==0 );
  pIter->pFile = pSorter->pTemp1;
  pIter->iReadOff = iStart;
  pIter->nAlloc = 128;
  pIter->aAlloc = (u8 *)sqlite3DbMallocRaw(db, pIter->nAlloc);
  pIter->nBuffer = nBuf;
  pIter->aBuffer = (u8 *)sqlite3DbMallocRaw(db, nBuf);

  if( !pIter->aBuffer ){
    rc = SQLITE_NOMEM;
  }else{
    int iBuf;

    iBuf = iStart % nBuf;
    if( iBuf ){
      int nRead = nBuf - iBuf;
      if( (iStart + nRead) > pSorter->iWriteOff ){
        nRead = (int)(pSorter->iWriteOff - iStart);
      }
      rc = sqlite3OsRead(
          pSorter->pTemp1, &pIter->aBuffer[iBuf], nRead, iStart
      );
      assert( rc!=SQLITE_IOERR_SHORT_READ );
    }

    if( rc==SQLITE_OK ){
      u64 nByte;                       /* Size of PMA in bytes */


      pIter->iEof = pSorter->iWriteOff;
      rc = vdbeSorterIterVarint(db, pIter, &nByte);
      pIter->iEof = pIter->iReadOff + nByte;
      *pnByte += nByte;
    }
  }

  if( rc==SQLITE_OK ){
    rc = vdbeSorterIterNext(db, pIter);
  }
  return rc;
}


................................................................................
** is true and key1 contains even a single NULL value, it is considered to
** be less than key2. Even if key2 also contains NULL values.
**
** If pKey2 is passed a NULL pointer, then it is assumed that the pCsr->aSpace
** has been allocated and contains an unpacked record that is used as key2.
*/
static void vdbeSorterCompare(
  const VdbeCursor *pCsr,         /* Cursor object (for pKeyInfo) */
  int bOmitRowid,                 /* Ignore rowid field at end of keys */
  const void *pKey1, int nKey1,   /* Left side of comparison */
  const void *pKey2, int nKey2,   /* Right side of comparison */
  int *pRes                       /* OUT: Result of comparison */
){
  KeyInfo *pKeyInfo = pCsr->pKeyInfo;
  VdbeSorter *pSorter = pCsr->pSorter;
  UnpackedRecord *r2 = pSorter->pUnpacked;
  int i;

................................................................................
}

/*
** This function is called to compare two iterator keys when merging 
** multiple b-tree segments. Parameter iOut is the index of the aTree[] 
** value to recalculate.
*/
static int vdbeSorterDoCompare(const VdbeCursor *pCsr, int iOut){
  VdbeSorter *pSorter = pCsr->pSorter;
  int i1;
  int i2;
  int iRes;
  VdbeSorterIter *p1;
  VdbeSorterIter *p2;

................................................................................
}

/*
** Merge the two sorted lists p1 and p2 into a single list.
** Set *ppOut to the head of the new list.
*/
static void vdbeSorterMerge(
  const VdbeCursor *pCsr,         /* For pKeyInfo */
  SorterRecord *p1,               /* First list to merge */
  SorterRecord *p2,               /* Second list to merge */
  SorterRecord **ppOut            /* OUT: Head of merged list */
){
  SorterRecord *pFinal = 0;
  SorterRecord **pp = &pFinal;
  void *pVal2 = p2 ? p2->pVal : 0;
................................................................................
}

/*
** Sort the linked list of records headed at pCsr->pRecord. Return SQLITE_OK
** if successful, or an SQLite error code (i.e. SQLITE_NOMEM) if an error
** occurs.
*/
static int vdbeSorterSort(const VdbeCursor *pCsr){
  int i;
  SorterRecord **aSlot;
  SorterRecord *p;
  VdbeSorter *pSorter = pCsr->pSorter;

  aSlot = (SorterRecord **)sqlite3MallocZero(64 * sizeof(SorterRecord *));
  if( !aSlot ){
................................................................................
  }
  pSorter->pRecord = p;

  sqlite3_free(aSlot);
  return SQLITE_OK;
}

/*
** Initialize a file-writer object.
*/
static void fileWriterInit(
  sqlite3 *db,                    /* Database (for malloc) */
  sqlite3_file *pFile,            /* File to write to */
  FileWriter *p,                  /* Object to populate */
  i64 iStart                      /* Offset of pFile to begin writing at */
){
  int nBuf = sqlite3BtreeGetPageSize(db->aDb[0].pBt);

  memset(p, 0, sizeof(FileWriter));
  p->aBuffer = (u8 *)sqlite3DbMallocRaw(db, nBuf);
  if( !p->aBuffer ){
    p->eFWErr = SQLITE_NOMEM;
  }else{
    p->iBufEnd = p->iBufStart = (iStart % nBuf);
    p->iWriteOff = iStart - p->iBufStart;
    p->nBuffer = nBuf;
    p->pFile = pFile;
  }
}

/*
** Write nData bytes of data to the file-write object. Return SQLITE_OK
** if successful, or an SQLite error code if an error occurs.
*/
static void fileWriterWrite(FileWriter *p, u8 *pData, int nData){
  int nRem = nData;
  while( nRem>0 && p->eFWErr==0 ){
    int nCopy = nRem;
    if( nCopy>(p->nBuffer - p->iBufEnd) ){
      nCopy = p->nBuffer - p->iBufEnd;
    }

    memcpy(&p->aBuffer[p->iBufEnd], &pData[nData-nRem], nCopy);
    p->iBufEnd += nCopy;
    if( p->iBufEnd==p->nBuffer ){
      p->eFWErr = sqlite3OsWrite(p->pFile, 
          &p->aBuffer[p->iBufStart], p->iBufEnd - p->iBufStart, 
          p->iWriteOff + p->iBufStart
      );
      p->iBufStart = p->iBufEnd = 0;
      p->iWriteOff += p->nBuffer;
    }
    assert( p->iBufEnd<p->nBuffer );

    nRem -= nCopy;
  }
}

/*
** Flush any buffered data to disk and clean up the file-writer object.
** The results of using the file-writer after this call are undefined.
** Return SQLITE_OK if flushing the buffered data succeeds or is not 
** required. Otherwise, return an SQLite error code.
**
** Before returning, set *piEof to the offset immediately following the
** last byte written to the file.
*/
static int fileWriterFinish(sqlite3 *db, FileWriter *p, i64 *piEof){
  int rc;
  if( p->eFWErr==0 && ALWAYS(p->aBuffer) && p->iBufEnd>p->iBufStart ){
    p->eFWErr = sqlite3OsWrite(p->pFile, 
        &p->aBuffer[p->iBufStart], p->iBufEnd - p->iBufStart, 
        p->iWriteOff + p->iBufStart
    );
  }
  *piEof = (p->iWriteOff + p->iBufEnd);
  sqlite3DbFree(db, p->aBuffer);
  rc = p->eFWErr;
  memset(p, 0, sizeof(FileWriter));
  return rc;
}

/*
** Write value iVal encoded as a varint to the file-write object. Return 
** SQLITE_OK if successful, or an SQLite error code if an error occurs.
*/
static void fileWriterWriteVarint(FileWriter *p, u64 iVal){
  int nByte; 
  u8 aByte[10];
  nByte = sqlite3PutVarint(aByte, iVal);
  fileWriterWrite(p, aByte, nByte);
}

/*
** Write the current contents of the in-memory linked-list to a PMA. Return
** SQLITE_OK if successful, or an SQLite error code otherwise.
**
** The format of a PMA is:
**
................................................................................
**     * A varint. This varint contains the total number of bytes of content
**       in the PMA (not including the varint itself).
**
**     * One or more records packed end-to-end in order of ascending keys. 
**       Each record consists of a varint followed by a blob of data (the 
**       key). The varint is the number of bytes in the blob of data.
*/
static int vdbeSorterListToPMA(sqlite3 *db, const VdbeCursor *pCsr){
  int rc = SQLITE_OK;             /* Return code */
  VdbeSorter *pSorter = pCsr->pSorter;
  FileWriter writer;

  memset(&writer, 0, sizeof(FileWriter));

  if( pSorter->nInMemory==0 ){
    assert( pSorter->pRecord==0 );
    return rc;
  }

  rc = vdbeSorterSort(pCsr);
................................................................................
    rc = vdbeSorterOpenTempFile(db, &pSorter->pTemp1);
    assert( rc!=SQLITE_OK || pSorter->pTemp1 );
    assert( pSorter->iWriteOff==0 );
    assert( pSorter->nPMA==0 );
  }

  if( rc==SQLITE_OK ){

    SorterRecord *p;
    SorterRecord *pNext = 0;


    fileWriterInit(db, pSorter->pTemp1, &writer, pSorter->iWriteOff);
    pSorter->nPMA++;

    fileWriterWriteVarint(&writer, pSorter->nInMemory);
    for(p=pSorter->pRecord; p; p=pNext){
      pNext = p->pNext;
      fileWriterWriteVarint(&writer, p->nVal);
      fileWriterWrite(&writer, p->pVal, p->nVal);






      sqlite3DbFree(db, p);
    }














    pSorter->pRecord = p;
    rc = fileWriterFinish(db, &writer, &pSorter->iWriteOff);
  }

  return rc;
}

/*
** Add a record to the sorter.
*/
int sqlite3VdbeSorterWrite(
  sqlite3 *db,                    /* Database handle */
  const VdbeCursor *pCsr,               /* Sorter cursor */
  Mem *pVal                       /* Memory cell containing record */
){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc = SQLITE_OK;             /* Return Code */
  SorterRecord *pNew;             /* New list element */

  assert( pSorter );
................................................................................
  **   * The total memory allocated for the in-memory list is greater 
  **     than (page-size * 10) and sqlite3HeapNearlyFull() returns true.
  */
  if( rc==SQLITE_OK && pSorter->mxPmaSize>0 && (
        (pSorter->nInMemory>pSorter->mxPmaSize)
     || (pSorter->nInMemory>pSorter->mnPmaSize && sqlite3HeapNearlyFull())
  )){
#ifdef SQLITE_DEBUG
    i64 nExpect = pSorter->iWriteOff
                + sqlite3VarintLen(pSorter->nInMemory)
                + pSorter->nInMemory;
#endif
    rc = vdbeSorterListToPMA(db, pCsr);
    pSorter->nInMemory = 0;
    assert( rc!=SQLITE_OK || (nExpect==pSorter->iWriteOff) );
  }

  return rc;
}

/*
** Helper function for sqlite3VdbeSorterRewind(). 
*/
static int vdbeSorterInitMerge(
  sqlite3 *db,                    /* Database handle */
  const VdbeCursor *pCsr,         /* Cursor handle for this sorter */
  i64 *pnByte                     /* Sum of bytes in all opened PMAs */
){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc = SQLITE_OK;             /* Return code */
  int i;                          /* Used to iterator through aIter[] */
  i64 nByte = 0;                  /* Total bytes in all opened PMAs */

................................................................................
  return rc;
}

/*
** Once the sorter has been populated, this function is called to prepare
** for iterating through its contents in sorted order.
*/
int sqlite3VdbeSorterRewind(sqlite3 *db, const VdbeCursor *pCsr, int *pbEof){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc;                         /* Return code */
  sqlite3_file *pTemp2 = 0;       /* Second temp file to use */
  i64 iWrite2 = 0;                /* Write offset for pTemp2 */
  int nIter;                      /* Number of iterators used */
  int nByte;                      /* Bytes of space required for aIter/aTree */
  int N = 2;                      /* Power of 2 >= nIter */
................................................................................
  ** from the in-memory list.  */
  if( pSorter->nPMA==0 ){
    *pbEof = !pSorter->pRecord;
    assert( pSorter->aTree==0 );
    return vdbeSorterSort(pCsr);
  }

  /* Write the current in-memory list to a PMA. */
  rc = vdbeSorterListToPMA(db, pCsr);
  if( rc!=SQLITE_OK ) return rc;

  /* Allocate space for aIter[] and aTree[]. */
  nIter = pSorter->nPMA;
  if( nIter>SORTER_MAX_MERGE_COUNT ) nIter = SORTER_MAX_MERGE_COUNT;
  assert( nIter>0 );
................................................................................
  do {
    int iNew;                     /* Index of new, merged, PMA */

    for(iNew=0; 
        rc==SQLITE_OK && iNew*SORTER_MAX_MERGE_COUNT<pSorter->nPMA; 
        iNew++
    ){
      int rc2;                    /* Return code from fileWriterFinish() */
      FileWriter writer;          /* Object used to write to disk */
      i64 nWrite;                 /* Number of bytes in new PMA */

      memset(&writer, 0, sizeof(FileWriter));

      /* If there are SORTER_MAX_MERGE_COUNT or less PMAs in file pTemp1,
      ** initialize an iterator for each of them and break out of the loop.
      ** These iterators will be incrementally merged as the VDBE layer calls
      ** sqlite3VdbeSorterNext().
      **
      ** Otherwise, if pTemp1 contains more than SORTER_MAX_MERGE_COUNT PMAs,
................................................................................

      /* Open the second temp file, if it is not already open. */
      if( pTemp2==0 ){
        assert( iWrite2==0 );
        rc = vdbeSorterOpenTempFile(db, &pTemp2);
      }

      if( rc==SQLITE_OK ){




        int bEof = 0;
        fileWriterInit(db, pTemp2, &writer, iWrite2);
        fileWriterWriteVarint(&writer, nWrite);
        while( rc==SQLITE_OK && bEof==0 ){

          VdbeSorterIter *pIter = &pSorter->aIter[ pSorter->aTree[1] ];
          assert( pIter->pFile );





          fileWriterWriteVarint(&writer, pIter->nKey);
          fileWriterWrite(&writer, pIter->aKey, pIter->nKey);
          rc = sqlite3VdbeSorterNext(db, pCsr, &bEof);
        }

        rc2 = fileWriterFinish(db, &writer, &iWrite2);
        if( rc==SQLITE_OK ) rc = rc2;
      }
    }

    if( pSorter->nPMA<=SORTER_MAX_MERGE_COUNT ){
      break;
    }else{
      sqlite3_file *pTmp = pSorter->pTemp1;
................................................................................
  *pbEof = (pSorter->aIter[pSorter->aTree[1]].pFile==0);
  return rc;
}

/*
** Advance to the next element in the sorter.
*/
int sqlite3VdbeSorterNext(sqlite3 *db, const VdbeCursor *pCsr, int *pbEof){
  VdbeSorter *pSorter = pCsr->pSorter;
  int rc;                         /* Return code */

  if( pSorter->aTree ){
    int iPrev = pSorter->aTree[1];/* Index of iterator to advance */
    int i;                        /* Index of aTree[] to recalculate */

................................................................................
}

/*
** Return a pointer to a buffer owned by the sorter that contains the 
** current key.
*/
static void *vdbeSorterRowkey(
  const VdbeSorter *pSorter,      /* Sorter object */
  int *pnKey                      /* OUT: Size of current key in bytes */
){
  void *pKey;
  if( pSorter->aTree ){
    VdbeSorterIter *pIter;
    pIter = &pSorter->aIter[ pSorter->aTree[1] ];
    *pnKey = pIter->nKey;
................................................................................
  }
  return pKey;
}

/*
** Copy the current sorter key into the memory cell pOut.
*/
int sqlite3VdbeSorterRowkey(const VdbeCursor *pCsr, Mem *pOut){
  VdbeSorter *pSorter = pCsr->pSorter;
  void *pKey; int nKey;           /* Sorter key to copy into pOut */

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  if( sqlite3VdbeMemGrow(pOut, nKey, 0) ){
    return SQLITE_NOMEM;
  }
................................................................................
**
** If an error occurs, return an SQLite error code (i.e. SQLITE_NOMEM).
** Otherwise, set *pRes to a negative, zero or positive value if the
** key in pVal is smaller than, equal to or larger than the current sorter
** key.
*/
int sqlite3VdbeSorterCompare(
  const VdbeCursor *pCsr,         /* Sorter cursor */
  Mem *pVal,                      /* Value to compare to current sorter key */
  int *pRes                       /* OUT: Result of comparison */
){
  VdbeSorter *pSorter = pCsr->pSorter;
  void *pKey; int nKey;           /* Sorter key to compare pVal with */

  pKey = vdbeSorterRowkey(pSorter, &nKey);
  vdbeSorterCompare(pCsr, 1, pVal->z, pVal->n, pKey, nKey, pRes);
  return SQLITE_OK;
}

#endif /* #ifndef SQLITE_OMIT_MERGE_SORT */

/*
** Allocate a new Explain object
*/
void sqlite3ExplainBegin(Vdbe *pVdbe){
  if( pVdbe ){
    Explain *p;
    sqlite3BeginBenignMalloc();
    p = sqlite3_malloc( sizeof(Explain) );
    if( p ){
      memset(p, 0, sizeof(*p));
      p->pVdbe = pVdbe;
      sqlite3_free(pVdbe->pExplain);
      pVdbe->pExplain = p;
      sqlite3StrAccumInit(&p->str, p->zBase, sizeof(p->zBase),
                          SQLITE_MAX_LENGTH);
      p->str.useMalloc = 2;
    }else{

/*
** Allocate a new Explain object
*/
void sqlite3ExplainBegin(Vdbe *pVdbe){
  if( pVdbe ){
    Explain *p;
    sqlite3BeginBenignMalloc();
    p = (Explain *)sqlite3MallocZero( sizeof(Explain) );
    if( p ){

      p->pVdbe = pVdbe;
      sqlite3_free(pVdbe->pExplain);
      pVdbe->pExplain = p;
      sqlite3StrAccumInit(&p->str, p->zBase, sizeof(p->zBase),
                          SQLITE_MAX_LENGTH);
      p->str.useMalloc = 2;
    }else{

# 2012 August 6
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#***********************************************************************
#


set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix index5

do_test 1.1 {
  execsql {
    PRAGMA page_size = 1024;
    CREATE TABLE t1(x);
    BEGIN;
  }
  for {set i 0} {$i < 100000} {incr i} {
    execsql { INSERT INTO t1 VALUES(randstr(100,100)) }
  }
  execsql COMMIT
  execsql { 
    CREATE INDEX i1 ON t1(x);
    DROP INDEX I1;
    PRAGMA main.page_size;
  }
} {1024}

db close
testvfs tvfs
tvfs filter xWrite
tvfs script write_cb
proc write_cb {xCall file handle iOfst} {
  if {[file tail $file]=="test.db"} {
    lappend ::write_list [expr $iOfst/1024]
  }
  puts "$xCall $file $args"
}

do_test 1.2 {
  sqlite3 db test.db -vfs tvfs
  set ::write_list [list]
  execsql { CREATE INDEX i1 ON t1(x) }
} {}

do_test 1.3 {
  set nForward 0
  set nBackward 0
  set nNoncont 0
  set iPrev [lindex $::write_list 0]
  for {set i 1} {$i < [llength $::write_list]} {incr i} {
    set iNext [lindex $::write_list $i]
    if {$iNext==($iPrev+1)} {
      incr nForward
    } elseif {$iNext==($iPrev-1)} { 
      incr nBackward 
    } else {
      incr nNoncont
    }
    set iPrev $iNext
  }

  expr {$nForward > $nBackward}
} {1}
db close
tvfs delete

finish_test

  misc7.test mutex2.test notify2.test onefile.test pagerfault2.test 
  savepoint4.test savepoint6.test select9.test 
  speed1.test speed1p.test speed2.test speed3.test speed4.test 
  speed4p.test sqllimits1.test tkt2686.test thread001.test thread002.test
  thread003.test thread004.test thread005.test trans2.test vacuum3.test 
  incrvacuum_ioerr.test autovacuum_crash.test btree8.test shared_err.test
  vtab_err.test walslow.test walcrash.test walcrash3.test
  walthread.test rtree3.test indexfault.test 
}]
if {[info exists ::env(QUICKTEST_INCLUDE)]} {
  set allquicktests [concat $allquicktests $::env(QUICKTEST_INCLUDE)]
}

#############################################################################
# Start of tests

  misc7.test mutex2.test notify2.test onefile.test pagerfault2.test 
  savepoint4.test savepoint6.test select9.test 
  speed1.test speed1p.test speed2.test speed3.test speed4.test 
  speed4p.test sqllimits1.test tkt2686.test thread001.test thread002.test
  thread003.test thread004.test thread005.test trans2.test vacuum3.test 
  incrvacuum_ioerr.test autovacuum_crash.test btree8.test shared_err.test
  vtab_err.test walslow.test walcrash.test walcrash3.test
  walthread.test rtree3.test indexfault.test securedel2.test
}]
if {[info exists ::env(QUICKTEST_INCLUDE)]} {
  set allquicktests [concat $allquicktests $::env(QUICKTEST_INCLUDE)]
}

#############################################################################
# Start of tests

# 2012 August 7
#
# The author disclaims copyright to this source code.  In place of
# a legal notice, here is a blessing:
#
#    May you do good and not evil.
#    May you find forgiveness for yourself and forgive others.
#    May you share freely, never taking more than you give.
#
#*************************************************************************
#
# Tests for the secure_delete pragma.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set ::testprefix securedel2

# Generate 1000 pseudo-random 64-bit blobs.
#
for {set i 1} {$i <= 1000} {incr i} {
  set aBlob($i) [string range [db one {SELECT quote(randomblob(8))}] 2 end-1]
}

proc detect_blob_prepare {zFile} {
  set nByte [file size $zFile]
  set ::detect_blob_data [hexio_read $zFile 0 $nByte]
}

proc detect_blob {zFile iBlob} {
  if {$zFile != ""} { detect_blob_prepare $zFile }
  string match "*$::aBlob($iBlob)*" $::detect_blob_data
}

do_test 1.1 {
  execsql { PRAGMA secure_delete = 1 }
  execsql { PRAGMA auto_vacuum = 0 }
  execsql { CREATE TABLE t1(x, y) }
  for {set i 1} {$i <= 1000} {incr i} {
    set x "X'[string repeat $aBlob($i) 1]'"
    set y "X'[string repeat $aBlob($i) 500]'"
    execsql "INSERT INTO t1 VALUES($x, $y)"
  }
} {}

do_test         1.2   { detect_blob test.db 1 } {1}

forcecopy test.db test.db.bak
do_execsql_test 1.3.1 { PRAGMA secure_delete = 0 } {0}
do_execsql_test 1.3.2 { DELETE FROM t1 WHERE rowid = 1 }
do_test         1.3.3 { detect_blob test.db 1 } {1}

db close
forcecopy test.db.bak test.db
sqlite3 db test.db
do_execsql_test 1.4.1 { PRAGMA secure_delete = 1 } {1}
do_execsql_test 1.4.2 { DELETE FROM t1 WHERE rowid = 1 }
do_test         1.4.3 { detect_blob test.db 1 } {0}

do_execsql_test 1.5.1 { DELETE FROM t1 WHERE rowid>850 } {}
do_test 1.5.2 { 
  set n 0
  detect_blob_prepare test.db
  for {set i 851} {$i <= 1000} {incr i 5} {
    incr n [detect_blob {} $i]
  }
  set n
} {0}

db close
sqlite3 db test.db
do_test 1.6.1 { 
  execsql {
    PRAGMA cache_size = 200;
    PRAGMA secure_delete = 1;
    CREATE TABLE t2(x);
    SELECT * FROM t1;
  }
  for {set i 100} {$i < 5000} {incr i} {
    execsql { INSERT INTO t2 VALUES(randomblob($i)) }
  }
  execsql { DELETE FROM t1 }
} {}

do_test 1.6.2 { 
  set n 0
  detect_blob_prepare test.db
  for {set i 2} {$i <= 850} {incr i 5} {
    incr n [detect_blob {} $i]
  }
  set n
} {0}

finish_test

#***********************************************************************
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix spellfix



register_spellfix_module db

set vocab {
rabbi rabbit rabbits rabble rabid rabies raccoon raccoons race raced racer
racers races racetrack racial racially racing rack racked racket racketeer
racketeering racketeers rackets racking racks radar radars radial radially
radian radiance radiant radiantly radiate radiated radiates radiating radiation
................................................................................
  foreach word $vocab {
    execsql { INSERT INTO t1(word) VALUES($word) }
  }
} {}

foreach {tn word res} {
  1   raxpi*     {rasping 5 rasped 5 raspberry 6 rasp 4 rasps 4}
  2   ril*       {rail 4 railway 4 railing 4 rails 4 railways 4}
  3   rilis*     {realist 6 realistic 6 realistically 6 realists 6 realism 6}
  4   reail*     {realities 3 reality 3 real 3 realest 3 realist 3}
  5   ras*       {rasp 3 rash 3 rasped 3 rasping 3 rasps 3}
  6   realistss* {realists 8 realigns 8 realistic 9 realistically 9 realest 7}
  7   realistss  {realists 8 realist 7 realigns 8 realistic 9 realest 7}
  8   rllation*  {realities 9 reality 7 rallied 7 railed 4}
  9   renstom*   {rainstorm 8 ransomer 6 ransom 6 ransoming 6 ransoms 6}
} {
  do_execsql_test 1.2.$tn {
    SELECT word, matchlen FROM t1 WHERE word MATCH $word LIMIT 5

  } $res
}


do_execsql_test 2.1 {
  CREATE VIRTUAL TABLE t2 USING spellfix1;
  INSERT INTO t2 (word, soundslike) VALUES('school', 'skuul');
................................................................................
  foreach w $vocab {
    execsql { INSERT INTO t3(word) VALUES($w) }
  }
} {}

breakpoint
foreach {tn word res} {
  1   kos*     {kosher 3 kiosk 4 kudo 2 kappa 1 keypad 1}
  2   kellj*   {killjoy 5 killed 4 killingly 4 kill 4 killer 4}
  3   kellj    {kill 4 kills 5 killjoy 7 keel 4 killed 6}
} {
  do_execsql_test 1.2.$tn {
    SELECT word, matchlen FROM t3 WHERE word MATCH $word LIMIT 5

  } $res
} 

finish_test

#***********************************************************************
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix spellfix

ifcapable !vtab { finish_test ; return }

register_spellfix_module db

set vocab {
rabbi rabbit rabbits rabble rabid rabies raccoon raccoons race raced racer
racers races racetrack racial racially racing rack racked racket racketeer
racketeering racketeers rackets racking racks radar radars radial radially
radian radiance radiant radiantly radiate radiated radiates radiating radiation
................................................................................
  foreach word $vocab {
    execsql { INSERT INTO t1(word) VALUES($word) }
  }
} {}

foreach {tn word res} {
  1   raxpi*     {rasping 5 rasped 5 raspberry 6 rasp 4 rasps 4}
  2   ril*       {rail 4 railed 4 railer 4 railers 4 railing 4}
  3   rilis*     {realism 6 realist 6 realistic 6 realistically 6 realists 6}
  4   reail*     {real 3 realest 3 realign 3 realigned 3 realigning 3}
  5   ras*       {rascal 3 rascally 3 rascals 3 rash 3 rasher 3}
  6   realistss* {realists 8 realigns 8 realistic 9 realistically 9 realest 7}
  7   realistss  {realists 8 realist 7 realigns 8 realistic 9 realest 7}
  8   rllation*  {realities 9 reality 7 rallied 7 railed 4}
  9   renstom*   {rainstorm 8 ransom 6 ransomer 6 ransoming 6 ransoms 6}
} {
  do_execsql_test 1.2.$tn {
    SELECT word, matchlen FROM t1 WHERE word MATCH $word 
     ORDER BY score, word LIMIT 5
  } $res
}


do_execsql_test 2.1 {
  CREATE VIRTUAL TABLE t2 USING spellfix1;
  INSERT INTO t2 (word, soundslike) VALUES('school', 'skuul');
................................................................................
  foreach w $vocab {
    execsql { INSERT INTO t3(word) VALUES($w) }
  }
} {}

breakpoint
foreach {tn word res} {
  1   kos*     {kosher 3 kiosk 4 kudo 2 kiss 3 kissed 3}
  2   kellj*   {killjoy 5 kill 4 killed 4 killer 4 killers 4}
  3   kellj    {kill 4 kills 5 killjoy 7 keel 4 killed 6}
} {
  do_execsql_test 1.2.$tn {
    SELECT word, matchlen FROM t3 WHERE word MATCH $word
     ORDER BY score, word LIMIT 5
  } $res
} 

finish_test

  }

  file mkdir walro

  do_test 1.1.1 {
    code2 { sqlite3 db2 test.db }
    sql2 { 

      PRAGMA journal_mode = WAL;
      CREATE TABLE t1(x, y);
      INSERT INTO t1 VALUES('a', 'b');
    }
    file exists test.db-shm
  } {1}

................................................................................

  do_test 2.1.1 {
    testvfs tv -default 1 -fullshm 1
    tv script tv_hook
    tv filter {}
    code1 { sqlite3 db test.db }
    csql1 { 

      PRAGMA journal_mode = WAL;
      BEGIN;
        CREATE TABLE t2(x, y);
        INSERT INTO t2 VALUES('abc', 'xyz');
        INSERT INTO t2 SELECT x||y, y||x FROM t2;
        INSERT INTO t2 SELECT x||y, y||x FROM t2;
      COMMIT;

  }

  file mkdir walro

  do_test 1.1.1 {
    code2 { sqlite3 db2 test.db }
    sql2 { 
      PRAGMA auto_vacuum = 0;
      PRAGMA journal_mode = WAL;
      CREATE TABLE t1(x, y);
      INSERT INTO t1 VALUES('a', 'b');
    }
    file exists test.db-shm
  } {1}

................................................................................

  do_test 2.1.1 {
    testvfs tv -default 1 -fullshm 1
    tv script tv_hook
    tv filter {}
    code1 { sqlite3 db test.db }
    csql1 { 
      PRAGMA auto_vacuum = 0;
      PRAGMA journal_mode = WAL;
      BEGIN;
        CREATE TABLE t2(x, y);
        INSERT INTO t2 VALUES('abc', 'xyz');
        INSERT INTO t2 SELECT x||y, y||x FROM t2;
        INSERT INTO t2 SELECT x||y, y||x FROM t2;
      COMMIT;

      error "Failed read transaction: $results"
    }
  }

  proc write_transaction {} {
    db eval {
      BEGIN;
        INSERT INTO t1 VALUES(randomblob(100));
        INSERT INTO t1 VALUES(randomblob(100));
        INSERT INTO t1 SELECT md5sum(x) FROM t1;
      COMMIT;
    }
  }

  # Turn off auto-checkpoint. Otherwise, an auto-checkpoint run by a
  # writer may cause the dedicated checkpoint thread to return an

      error "Failed read transaction: $results"
    }
  }

  proc write_transaction {} {
    db eval {
      BEGIN;
        INSERT INTO t1 VALUES(randomblob(101 + $::E(pid)));
        INSERT INTO t1 VALUES(randomblob(101 + $::E(pid)));
        INSERT INTO t1 SELECT md5sum(x) FROM t1;
      COMMIT;
    }
  }

  # Turn off auto-checkpoint. Otherwise, an auto-checkpoint run by a
  # writer may cause the dedicated checkpoint thread to return an

@ECHO OFF

::
:: build-all-msvc.bat --
::
:: Multi-Platform Build Tool for MSVC
::

SETLOCAL

REM SET __ECHO=ECHO
REM SET __ECHO2=ECHO
IF NOT DEFINED _AECHO (SET _AECHO=REM)
IF NOT DEFINED _CECHO (SET _CECHO=REM)
IF NOT DEFINED _VECHO (SET _VECHO=REM)

%_AECHO% Running %0 %*

REM SET DFLAGS=/L

%_VECHO% DFlags = '%DFLAGS%'

SET FFLAGS=/V /F /G /H /I /R /Y /Z

%_VECHO% FFlags = '%FFLAGS%'

SET ROOT=%~dp0\..
SET ROOT=%ROOT:\\=\%

%_VECHO% Root = '%ROOT%'

REM
REM NOTE: The first and only argument to this batch file should be the output
REM       directory where the platform-specific binary directories should be
REM       created.
REM
SET BINARYDIRECTORY=%1

IF NOT DEFINED BINARYDIRECTORY (
  GOTO usage
)

%_VECHO% BinaryDirectory = '%BINARYDIRECTORY%'

SET DUMMY=%2

IF DEFINED DUMMY (
  GOTO usage
)

REM
REM NOTE: From this point, we need a clean error level.  Reset it now.
REM
CALL :fn_ResetErrorLevel

REM
REM NOTE: Change the current directory to the root of the source tree, saving
REM       the current directory on the directory stack.
REM
%__ECHO2% PUSHD "%ROOT%"

IF ERRORLEVEL 1 (
  ECHO Could not change directory to "%ROOT%".
  GOTO errors
)

REM
REM NOTE: This batch file requires the ComSpec environment variable to be set,
REM       typically to something like "C:\Windows\System32\cmd.exe".
REM
IF NOT DEFINED ComSpec (
  ECHO The ComSpec environment variable must be defined.
  GOTO errors
)

REM
REM NOTE: This batch file requires the VcInstallDir environment variable to be
REM       set.  Tyipcally, this means this batch file needs to be run from an
REM       MSVC command prompt.
REM
IF NOT DEFINED VCINSTALLDIR (
  ECHO The VCINSTALLDIR environment variable must be defined.
  GOTO errors
)

REM
REM NOTE: If the list of platforms is not already set, use the default list.
REM
IF NOT DEFINED PLATFORMS (
  SET PLATFORMS=x86 x86_amd64 x86_arm
)

%_VECHO% Platforms = '%PLATFORMS%'

REM
REM NOTE: Setup environment variables to translate between the MSVC platform
REM       names and the names to be used for the platform-specific binary
REM       directories.
REM
SET x86_NAME=x86
SET x86_amd64_NAME=x64
SET x86_arm_NAME=ARM

%_VECHO% x86_Name = '%x86_NAME%'
%_VECHO% x86_amd64_Name = '%x86_amd64_NAME%'
%_VECHO% x86_arm_Name = '%x86_arm_NAME%'

REM
REM NOTE: Check for the external tools needed during the build process ^(i.e.
REM       those that do not get compiled as part of the build process itself^)
REM       along the PATH.
REM
FOR %%T IN (gawk.exe tclsh85.exe) DO (
  SET %%T_PATH=%%~dp$PATH:T
)

REM
REM NOTE: Set the TOOLPATH variable to contain all the directories where the
REM       external tools were found in the search above.
REM
SET TOOLPATH=%gawk.exe_PATH%;%tclsh85.exe_PATH%

%_VECHO% ToolPath = '%TOOLPATH%'

REM
REM NOTE: Check for MSVC 2012 because the Windows SDK directory handling is
REM       slightly different for that version.
REM
IF "%VisualStudioVersion%" == "11.0" (
  SET SET_NSDKLIBPATH=1
) ELSE (
  CALL :fn_UnsetVariable SET_NSDKLIBPATH
)

REM
REM NOTE: This is the outer loop.  There should be exactly one iteration per
REM       platform.
REM
FOR %%P IN (%PLATFORMS%) DO (
  REM
  REM NOTE: Using the MSVC platform name, lookup the simpler platform name to
  REM       be used for the name of the platform-specific binary directory via
  REM       the environment variables setup earlier.
  REM
  CALL :fn_SetVariable %%P_NAME PLATFORMNAME

  REM
  REM NOTE: This is the inner loop.  There should be exactly one iteration.
  REM       This loop is necessary because the PlatformName environment
  REM       variable was set above and that value is needed by some of the
  REM       commands contained in the inner loop.  If these commands were
  REM       directly contained in the outer loop, the PlatformName environment
  REM       variable would be stuck with its initial empty value instead.
  REM
  FOR /F "tokens=2* delims==" %%D IN ('SET PLATFORMNAME') DO (
    REM
    REM NOTE: Attempt to clean the environment of all variables used by MSVC
    REM       and/or Visual Studio.  This block may need to be updated in the
    REM       future to account for additional environment variables.
    REM
    CALL :fn_UnsetVariable DevEnvDir
    CALL :fn_UnsetVariable ExtensionSdkDir
    CALL :fn_UnsetVariable Framework35Version
    CALL :fn_UnsetVariable FrameworkDir
    CALL :fn_UnsetVariable FrameworkDir32
    CALL :fn_UnsetVariable FrameworkVersion
    CALL :fn_UnsetVariable FrameworkVersion32
    CALL :fn_UnsetVariable FSHARPINSTALLDIR
    CALL :fn_UnsetVariable INCLUDE
    CALL :fn_UnsetVariable LIB
    CALL :fn_UnsetVariable LIBPATH
    CALL :fn_UnsetVariable Platform
    REM CALL :fn_UnsetVariable VCINSTALLDIR
    CALL :fn_UnsetVariable VSINSTALLDIR
    CALL :fn_UnsetVariable WindowsSdkDir
    CALL :fn_UnsetVariable WindowsSdkDir_35
    CALL :fn_UnsetVariable WindowsSdkDir_old

    REM
    REM NOTE: Reset the PATH here to the absolute bare minimum required.
    REM
    SET PATH=%TOOLPATH%;%SystemRoot%\System32;%SystemRoot%

    REM
    REM NOTE: Launch a nested command shell to perform the following steps:
    REM
    REM       1. Setup the MSVC environment for this platform using the
    REM          official batch file.
    REM
    REM       2. Make sure that no stale build output files are present.
    REM
    REM       3. Build the "sqlite3.dll" and "sqlite3.lib" binaries for this
    REM          platform.
    REM
    REM       4. Copy the "sqlite3.dll" and "sqlite3.lib" binaries for this
    REM          platform to the platform-specific directory beneath the
    REM          binary directory.
    REM
    "%ComSpec%" /C (
      REM
      REM NOTE: Attempt to setup the MSVC environment for this platform.
      REM
      %__ECHO% CALL "%VCINSTALLDIR%\vcvarsall.bat" %%P

      IF ERRORLEVEL 1 (
        ECHO Failed to call "%VCINSTALLDIR%\vcvarsall.bat" for platform %%P.
        GOTO errors
      )

      REM
      REM NOTE: If this batch file is not running in "what-if" mode, check to
      REM       be sure we were actually able to setup the MSVC environment as
      REM       current versions of their official batch file do not set the
      REM       exit code upon failure.
      REM
      IF NOT DEFINED __ECHO (
        IF NOT DEFINED WindowsSdkDir (
          ECHO Cannot build, Windows SDK not found for platform %%P.
          GOTO errors
        )
      )

      REM
      REM NOTE: When using MSVC 2012, the native SDK path cannot simply use
      REM       the "lib" sub-directory beneath the location specified in the
      REM       WindowsSdkDir environment variable because that location does
      REM       not actually contain the necessary library files for x86.
      REM       This must be done for each iteration because it relies upon
      REM       the WindowsSdkDir environment variable being set by the batch
      REM       file used to setup the MSVC environment.
      REM
      IF DEFINED SET_NSDKLIBPATH (
        CALL :fn_SetVariable WindowsSdkDir NSDKLIBPATH
        CALL :fn_AppendVariable NSDKLIBPATH \lib\win8\um\x86
      )

      REM
      REM NOTE: Unless prevented from doing so, invoke NMAKE with the MSVC
      REM       makefile to clean any stale build output from previous
      REM       iterations of this loop and/or previous runs of this batch
      REM       file, etc.
      REM
      IF NOT DEFINED NOCLEAN (
        %__ECHO% nmake -f Makefile.msc clean

        IF ERRORLEVEL 1 (
          ECHO Failed to clean for platform %%P.
          GOTO errors
        )
      ) ELSE (
        REM
        REM NOTE: Even when the cleaning step has been disabled, we still need
        REM       to remove the build output for the files we are specifically
        REM       wanting to build for each platform.
        REM
        %__ECHO% DEL /Q sqlite3.dll sqlite3.lib sqlite3.pdb
      )

      REM
      REM NOTE: Invoke NMAKE with the MSVC makefile to build the "sqlite3.dll"
      REM       binary.  The x86 compiler will be used to compile the native
      REM       command line tools needed during the build process itself.
      REM       Also, disable looking for and/or linking to the native Tcl
      REM       runtime library.
      REM
      %__ECHO% nmake -f Makefile.msc sqlite3.dll "NCC=""%VCINSTALLDIR%\bin\cl.exe""" USE_NATIVE_LIBPATHS=1 NO_TCL=1 %NMAKE_ARGS%

      IF ERRORLEVEL 1 (
        ECHO Failed to build "sqlite3.dll" for platform %%P.
        GOTO errors
      )

      REM
      REM NOTE: Copy the "sqlite3.dll" file to the platform-specific directory
      REM       beneath the binary directory.
      REM
      %__ECHO% XCOPY sqlite3.dll "%BINARYDIRECTORY%\%%D\" %FFLAGS% %DFLAGS%

      IF ERRORLEVEL 1 (
        ECHO Failed to copy "sqlite3.dll" to "%BINARYDIRECTORY%\%%D\".
        GOTO errors
      )

      REM
      REM NOTE: Copy the "sqlite3.lib" file to the platform-specific directory
      REM       beneath the binary directory.
      REM
      %__ECHO% XCOPY sqlite3.lib "%BINARYDIRECTORY%\%%D\" %FFLAGS% %DFLAGS%

      IF ERRORLEVEL 1 (
        ECHO Failed to copy "sqlite3.lib" to "%BINARYDIRECTORY%\%%D\".
        GOTO errors
      )

      REM
      REM NOTE: Copy the "sqlite3.pdb" file to the platform-specific directory
      REM       beneath the binary directory unless we are prevented from doing
      REM       so.
      REM
      IF NOT DEFINED NOSYMBOLS (
        %__ECHO% XCOPY sqlite3.pdb "%BINARYDIRECTORY%\%%D\" %FFLAGS% %DFLAGS%

        IF ERRORLEVEL 1 (
          ECHO Failed to copy "sqlite3.pdb" to "%BINARYDIRECTORY%\%%D\".
          GOTO errors
        )
      )
    )
  )

  REM
  REM NOTE: Handle any errors generated during the nested command shell.
  REM
  IF ERRORLEVEL 1 (
    GOTO errors
  )
)

REM
REM NOTE: Restore the saved current directory from the directory stack.
REM
%__ECHO2% POPD

IF ERRORLEVEL 1 (
  ECHO Could not restore directory.
  GOTO errors
)

REM
REM NOTE: If we get to this point, we have succeeded.
REM
GOTO no_errors

:fn_ResetErrorLevel
  VERIFY > NUL
  GOTO :EOF

:fn_SetErrorLevel
  VERIFY MAYBE 2> NUL
  GOTO :EOF

:fn_SetVariable
  SETLOCAL
  IF NOT DEFINED %1 GOTO :EOF
  IF "%2" == "" GOTO :EOF
  SET __ECHO_CMD=ECHO %%%1%%
  FOR /F "delims=" %%V IN ('%__ECHO_CMD%') DO (
    SET VALUE=%%V
  )
  ENDLOCAL && SET %2=%VALUE%
  GOTO :EOF

:fn_UnsetVariable
  IF NOT "%1" == "" (
    SET %1=
    CALL :fn_ResetErrorLevel
  )
  GOTO :EOF

:fn_AppendVariable
  SET __ECHO_CMD=ECHO %%%1%%
  IF DEFINED %1 (
    FOR /F "delims=" %%V IN ('%__ECHO_CMD%') DO (
      SET %1=%%V%~2
    )
  ) ELSE (
    SET %1=%~2
  )
  SET __ECHO_CMD=
  CALL :fn_ResetErrorLevel
  GOTO :EOF

:usage
  ECHO.
  ECHO Usage: %~nx0 ^<binaryDirectory^>
  ECHO.
  GOTO errors

:errors
  CALL :fn_SetErrorLevel
  ENDLOCAL
  ECHO.
  ECHO Failure, errors were encountered.
  GOTO end_of_file

:no_errors
  CALL :fn_ResetErrorLevel
  ENDLOCAL
  ECHO.
  ECHO Success, no errors were encountered.
  GOTO end_of_file

:end_of_file
%__ECHO% EXIT /B %ERRORLEVEL%

#!/usr/bin/tclsh
#
# This script is used to generate a VSIX (Visual Studio Extension) file for
# SQLite usable by Visual Studio.

proc fail { {error ""} {usage false} } {
  if {[string length $error] > 0} then {
    puts stdout $error
    if {!$usage} then {exit 1}
  }

  puts stdout "usage:\
[file tail [info nameofexecutable]]\
[file tail [info script]] <binaryDirectory> \[sourceDirectory\]"

  exit 1
}
 
proc getEnvironmentVariable { name } {
  #
  # NOTE: Returns the value of the specified environment variable or an empty
  #       string for environment variables that do not exist in the current
  #       process environment.
  #
  return [expr {[info exists ::env($name)] ? $::env($name) : ""}]
}
 
proc getTemporaryPath {} {
  #
  # NOTE: Returns the normalized path to the first temporary directory found
  #       in the typical set of environment variables used for that purpose
  #       or an empty string to signal a failure to locate such a directory.
  #
  set names [list]

  foreach name [list TEMP TMP] {
    lappend names [string toupper $name] [string tolower $name] \
        [string totitle $name]
  }

  foreach name $names {
    set value [getEnvironmentVariable $name]

    if {[string length $value] > 0} then {
      return [file normalize $value]
    }
  }

  return ""
}
 
proc appendArgs { args } {
  #
  # NOTE: Returns all passed arguments joined together as a single string with
  #       no intervening spaces between arguments.
  #
  eval append result $args
}
 
proc readFile { fileName } {
  #
  # NOTE: Reads and returns the entire contents of the specified file, which
  #       may contain binary data.
  #
  set file_id [open $fileName RDONLY]
  fconfigure $file_id -encoding binary -translation binary
  set result [read $file_id]
  close $file_id
  return $result
}
 
proc writeFile { fileName data } {
  #
  # NOTE: Writes the entire contents of the specified file, which may contain
  #       binary data.
  #
  set file_id [open $fileName {WRONLY CREAT TRUNC}]
  fconfigure $file_id -encoding binary -translation binary
  puts -nonewline $file_id $data
  close $file_id
  return ""
}
 
proc substFile { fileName } {
  #
  # NOTE: Performs all Tcl command, variable, and backslash substitutions in
  #       the specified file and then re-writes the contents of that same file
  #       with the substituted data.
  #
  return [writeFile $fileName [uplevel 1 [list subst [readFile $fileName]]]]
}
 
proc replacePlatform { fileName platformName } {
  #
  # NOTE: Returns the specified file name containing the platform name instead
  #       of platform placeholder tokens.
  #
  return [string map [list <platform> $platformName] $fileName]
}
 
set script [file normalize [info script]]

if {[string length $script] == 0} then {
  fail "script file currently being evaluated is unknown" true
}

set path [file dirname $script]
set rootName [file rootname [file tail $script]]

###############################################################################

#
# NOTE: Process and verify all the command line arguments.
#
set argc [llength $argv]
if {$argc != 1 && $argc != 2} then {fail}

set binaryDirectory [lindex $argv 0]

if {[string length $binaryDirectory] == 0} then {
  fail "invalid binary directory"
}

if {![file exists $binaryDirectory] || \
    ![file isdirectory $binaryDirectory]} then {
  fail "binary directory does not exist"
}

if {$argc == 2} then {
  set sourceDirectory [lindex $argv 1]
} else {
  #
  # NOTE: Assume that the source directory is the parent directory of the one
  #       that contains this script file.
  #
  set sourceDirectory [file dirname $path]
}

if {[string length $sourceDirectory] == 0} then {
  fail "invalid source directory"
}

if {![file exists $sourceDirectory] || \
    ![file isdirectory $sourceDirectory]} then {
  fail "source directory does not exist"
}

###############################################################################

#
# NOTE: Evaluate the user-specific customizations file, if it exists.
#
set userFile [file join $path [appendArgs \
    $rootName . $tcl_platform(user) .tcl]]

if {[file exists $userFile] && \
    [file isfile $userFile]} then {
  source $userFile
}

###############################################################################

set templateFile [file join $path win sqlite.vsix]

if {![file exists $templateFile] || \
    ![file isfile $templateFile]} then {
  fail [appendArgs "template file \"" $templateFile "\" does not exist"]
}

set currentDirectory [pwd]
set outputFile [file join $currentDirectory sqlite-output.vsix]

if {[file exists $outputFile]} then {
  fail [appendArgs "output file \"" $outputFile "\" already exists"]
}

###############################################################################

#
# NOTE: Make sure that a valid temporary directory exists.
#
set temporaryDirectory [getTemporaryPath]

if {[string length $temporaryDirectory] == 0 || \
    ![file exists $temporaryDirectory] || \
    ![file isdirectory $temporaryDirectory]} then {
  fail "cannot locate a usable temporary directory"
}

#
# NOTE: Setup the staging directory to have a unique name inside of the
#       configured temporary directory.
#
set stagingDirectory [file normalize [file join $temporaryDirectory \
    [appendArgs $rootName . [pid]]]]

###############################################################################

#
# NOTE: Configure the external zipping tool.  First, see if it has already
#       been pre-configured.  If not, try to query it from the environment.
#       Finally, fallback on the default of simply "zip", which will then
#       be assumed to exist somewhere along the PATH.
#
if {![info exists zip]} then {
  if {[info exists env(ZipTool)]} then {
    set zip $env(ZipTool)
  }
  if {![info exists zip] || ![file exists $zip]} then {
    set zip zip
  }
}

#
# NOTE: Configure the external unzipping tool.  First, see if it has already
#       been pre-configured.  If not, try to query it from the environment.
#       Finally, fallback on the default of simply "unzip", which will then
#       be assumed to exist somewhere along the PATH.
#
if {![info exists unzip]} then {
  if {[info exists env(UnZipTool)]} then {
    set unzip $env(UnZipTool)
  }
  if {![info exists unzip] || ![file exists $unzip]} then {
    set unzip unzip
  }
}

###############################################################################

#
# NOTE: Attempt to extract the SQLite version from the "sqlite3.h" header file
#       in the source directory.  This script assumes that the header file has
#       already been generated by the build process.
#
set pattern {^#define\s+SQLITE_VERSION\s+"(.*)"$}
set data [readFile [file join $sourceDirectory sqlite3.h]]

if {![regexp -line -- $pattern $data dummy version]} then {
  fail [appendArgs "cannot locate SQLITE_VERSION value in \"" \
      [file join $sourceDirectory sqlite3.h] \"]
}

###############################################################################

#
# NOTE: Setup the master file list data, including the necessary flags.
#
if {![info exists fileNames(source)]} then {
  set fileNames(source) [list "" "" "" \
      [file join $sourceDirectory sqlite3.h] \
      [file join $binaryDirectory <platform> sqlite3.lib] \
      [file join $binaryDirectory <platform> sqlite3.dll]]

  if {![info exists no(symbols)]} then {
    lappend fileNames(source) \
        [file join $binaryDirectory <platform> sqlite3.pdb]
  }
}

if {![info exists fileNames(destination)]} then {
  set fileNames(destination) [list \
      [file join $stagingDirectory extension.vsixmanifest] \
      [file join $stagingDirectory SDKManifest.xml] \
      [file join $stagingDirectory DesignTime CommonConfiguration \
          <platform> SQLite.WinRT.props] \
      [file join $stagingDirectory DesignTime CommonConfiguration \
          <platform> sqlite3.h] \
      [file join $stagingDirectory DesignTime CommonConfiguration \
          <platform> sqlite3.lib] \
      [file join $stagingDirectory Redist CommonConfiguration \
          <platform> sqlite3.dll]]

  if {![info exists no(symbols)]} then {
    lappend fileNames(destination) \
        [file join $stagingDirectory Redist Debug \
            <platform> sqlite3.pdb]
  }
}

if {![info exists fileNames(neutral)]} then {
  set fileNames(neutral) [list 1 1 1 1 0 0]

  if {![info exists no(symbols)]} then {
    lappend fileNames(neutral) 0
  }
}

if {![info exists fileNames(subst)]} then {
  set fileNames(subst) [list 1 1 1 0 0 0]

  if {![info exists no(symbols)]} then {
    lappend fileNames(subst) 0
  }
}

###############################################################################

#
# NOTE: Setup the list of platforms supported by this script.
#
if {![info exists platformNames]} then {
  set platformNames [list x86 x64 ARM]
}

###############################################################################

#
# NOTE: Make sure the staging directory exists, creating it if necessary.
#
file mkdir $stagingDirectory

#
# NOTE: Build the Tcl command used to extract the template package to the
#       staging directory.
#
set extractCommand [list exec -- $unzip $templateFile -d $stagingDirectory]

#
# NOTE: Extract the template package to the staging directory.
#
eval $extractCommand

###############################################################################

#
# NOTE: Process each file in the master file list.  There are actually four
#       parallel lists that contain the source file names, destination file
#       names, the platform-neutral flags, and the use-subst flags.  When the
#       platform-neutral flag is non-zero, the file is not platform-specific.
#       When the use-subst flag is non-zero, the file is considered to be a
#       text file that may contain Tcl variable and/or command replacements,
#       to be dynamically replaced during processing.  If the source file name
#       is an empty string, then the destination file name will be assumed to
#       already exist in the staging directory and will not be copied; however,
#       dynamic replacements may still be performed on the destination file
#       prior to the package being re-zipped.
#
foreach sourceFileName $fileNames(source) \
    destinationFileName $fileNames(destination) \
    isNeutral $fileNames(neutral) useSubst $fileNames(subst) {
  #
  # NOTE: If the current file is platform-neutral, then only one platform will
  #       be processed for it, namely "neutral"; otherwise, each supported
  #       platform will be processed for it individually.
  #
  foreach platformName [expr {$isNeutral ? [list neutral] : $platformNames}] {
    #
    # NOTE: Use the actual platform name in the destination file name.
    #
    set newDestinationFileName [replacePlatform $destinationFileName \
        $platformName]

    #
    # NOTE: Does the source file need to be copied to the destination file?
    #
    if {[string length $sourceFileName] > 0} then {
      #
      # NOTE: First, make sure the destination directory exists.
      #
      file mkdir [file dirname $newDestinationFileName]

      #
      # NOTE: Then, copy the source file to the destination file verbatim.
      #
      file copy [replacePlatform $sourceFileName $platformName] \
          $newDestinationFileName
    }

    #
    # NOTE: Does the destination file contain dynamic replacements that must
    #       be processed now?
    #
    if {$useSubst} then {
      #
      # NOTE: Perform any dynamic replacements contained in the destination
      #       file and then re-write it in-place.
      #
      substFile $newDestinationFileName
    }
  }
}

###############################################################################

#
# NOTE: Change the current directory to the staging directory so that the
#       external archive building tool can pickup the necessary files using
#       relative paths.
#
cd $stagingDirectory

#
# NOTE: Build the Tcl command used to archive the final package in the
#       output directory.
#
set archiveCommand [list exec -- $zip -r $outputFile *]

#
# NOTE: Build the final package archive in the output directory.
#
eval $archiveCommand

#
# NOTE: Change back to the previously saved current directory.
#
cd $currentDirectory

#
# NOTE: Cleanup the temporary staging directory.
#
file delete -force $stagingDirectory

###############################################################################

#
# NOTE: Success, emit the fully qualified path of the generated VSIX file.
#
puts stdout $outputFile