$(TOP)/ext/fts5/fts5_varint.c \
   $(TOP)/ext/fts5/fts5_vocab.c  \

fts5parse.c:	$(TOP)/ext/fts5/fts5parse.y lemon 
	cp $(TOP)/ext/fts5/fts5parse.y .
	rm -f fts5parse.h
	./lemon $(OPTS) fts5parse.y
	mv fts5parse.c fts5parse.c.orig
	cat fts5parse.c.orig | sed 's/yy/fts5yy/g' | sed 's/YY/fts5YY/g' \
		| sed 's/TOKEN/FTS5TOKEN/g' >> fts5parse.c

fts5parse.h: fts5parse.c

fts5.c: $(FTS5_SRC)
	$(TCLSH_CMD) $(TOP)/ext/fts5/tool/mkfts5c.tcl


fts5.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c fts5.c


# Rules to build the 'testfixture' application.
#
................................................................................
	rm -f shell.c sqlite3ext.h
	rm -f sqlite3_analyzer$(TEXE) sqlite3_analyzer.c
	rm -f sqlite-*-output.vsix
	rm -f mptester mptester.exe
	rm -f fuzzershell fuzzershell.exe
	rm -f fuzzcheck fuzzcheck.exe
	rm -f sqldiff sqldiff.exe


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

#
# Windows section
#

   $(TOP)/ext/fts5/fts5_varint.c \
   $(TOP)/ext/fts5/fts5_vocab.c  \

fts5parse.c:	$(TOP)/ext/fts5/fts5parse.y lemon 
	cp $(TOP)/ext/fts5/fts5parse.y .
	rm -f fts5parse.h
	./lemon $(OPTS) fts5parse.y




fts5parse.h: fts5parse.c

fts5.c: $(FTS5_SRC)
	$(TCLSH_CMD) $(TOP)/ext/fts5/tool/mkfts5c.tcl
	cp $(TOP)/ext/fts5/fts5.h .

fts5.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) -DSQLITE_CORE -c fts5.c


# Rules to build the 'testfixture' application.
#
................................................................................
	rm -f shell.c sqlite3ext.h
	rm -f sqlite3_analyzer$(TEXE) sqlite3_analyzer.c
	rm -f sqlite-*-output.vsix
	rm -f mptester mptester.exe
	rm -f fuzzershell fuzzershell.exe
	rm -f fuzzcheck fuzzcheck.exe
	rm -f sqldiff sqldiff.exe
	rm -f fts5.c fts5.h fts5parse.*

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

#
# Windows section
#

   $(TOP)\ext\fts5\fts5_varint.c \
   $(TOP)\ext\fts5\fts5_vocab.c

fts5parse.c:	$(TOP)\ext\fts5\fts5parse.y lemon.exe
	copy $(TOP)\ext\fts5\fts5parse.y .
	del /Q fts5parse.h 2>NUL
	.\lemon.exe $(REQ_FEATURE_FLAGS) $(OPT_FEATURE_FLAGS) $(OPTS) fts5parse.y
	move fts5parse.c fts5parse.c.orig
	type fts5parse.c.orig \
		| $(NAWK) "/.*/ { gsub(/yy/,\"fts5yy\");print }" \
		| $(NAWK) "/.*/ { gsub(/YY/,\"fts5YY\");print }" \
		| $(NAWK) "/.*/ { gsub(/TOKEN/,\"FTS5TOKEN\");print }" > $@

fts5parse.h: fts5parse.c

fts5.c: $(FTS5_SRC)
	$(TCLSH_CMD) $(TOP)\ext\fts5\tool\mkfts5c.tcl


fts5.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) $(NO_WARN) -DSQLITE_CORE -c fts5.c

fts5_ext.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) $(NO_WARN) -c fts5.c

................................................................................
	del /Q sqlite3.exe sqlite3.dll sqlite3.def 2>NUL
	del /Q sqlite3.c sqlite3-*.c 2>NUL
	del /Q sqlite3rc.h 2>NUL
	del /Q shell.c sqlite3ext.h 2>NUL
	del /Q sqlite3_analyzer.exe sqlite3_analyzer.c 2>NUL
	del /Q sqlite-*-output.vsix 2>NUL
	del /Q fuzzershell.exe fuzzcheck.exe sqldiff.exe 2>NUL
	del /Q fts5.c fts5parse.* 2>NUL

# Dynamic link library section.
#
dll: sqlite3.dll

sqlite3.def: libsqlite3.lib
	echo EXPORTS > sqlite3.def
	dumpbin /all libsqlite3.lib \
		| $(NAWK) "/ 1 _?sqlite3_/ { sub(/^.* _?/,\"\");print }" \
		| sort >> sqlite3.def

sqlite3.dll: $(LIBOBJ) $(LIBRESOBJS) $(CORE_LINK_DEP)
	$(LD) $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) /DLL $(CORE_LINK_OPTS) /OUT:$@ $(LIBOBJ) $(LIBRESOBJS) $(LTLIBS) $(TLIBS)

   $(TOP)\ext\fts5\fts5_varint.c \
   $(TOP)\ext\fts5\fts5_vocab.c

fts5parse.c:	$(TOP)\ext\fts5\fts5parse.y lemon.exe
	copy $(TOP)\ext\fts5\fts5parse.y .
	del /Q fts5parse.h 2>NUL
	.\lemon.exe $(REQ_FEATURE_FLAGS) $(OPT_FEATURE_FLAGS) $(OPTS) fts5parse.y






fts5parse.h: fts5parse.c

fts5.c: $(FTS5_SRC)
	$(TCLSH_CMD) $(TOP)\ext\fts5\tool\mkfts5c.tcl
	copy $(TOP)\ext\fts5\fts5.h .

fts5.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) $(CORE_COMPILE_OPTS) $(NO_WARN) -DSQLITE_CORE -c fts5.c

fts5_ext.lo:	fts5.c $(HDR) $(EXTHDR)
	$(LTCOMPILE) $(NO_WARN) -c fts5.c

................................................................................
	del /Q sqlite3.exe sqlite3.dll sqlite3.def 2>NUL
	del /Q sqlite3.c sqlite3-*.c 2>NUL
	del /Q sqlite3rc.h 2>NUL
	del /Q shell.c sqlite3ext.h 2>NUL
	del /Q sqlite3_analyzer.exe sqlite3_analyzer.c 2>NUL
	del /Q sqlite-*-output.vsix 2>NUL
	del /Q fuzzershell.exe fuzzcheck.exe sqldiff.exe 2>NUL
	del /Q fts5.c fts5.h fts5parse.* 2>NUL

# Dynamic link library section.
#
dll: sqlite3.dll

sqlite3.def: libsqlite3.lib
	echo EXPORTS > sqlite3.def
	dumpbin /all libsqlite3.lib \
		| $(NAWK) "/ 1 _?sqlite3_/ { sub(/^.* _?/,\"\");print }" \
		| sort >> sqlite3.def

sqlite3.dll: $(LIBOBJ) $(LIBRESOBJS) $(CORE_LINK_DEP)
	$(LD) $(LDFLAGS) $(LTLINKOPTS) $(LTLIBPATHS) /DLL $(CORE_LINK_OPTS) /OUT:$@ $(LIBOBJ) $(LIBRESOBJS) $(LTLIBS) $(TLIBS)

  assert( !p || (p>=aDoclist && p<=&aDoclist[nDoclist]) );

  if( p==0 ){
    p = aDoclist;
    p += sqlite3Fts3GetVarint(p, piDocid);
  }else{
    fts3PoslistCopy(0, &p);

    if( p>=&aDoclist[nDoclist] ){
      *pbEof = 1;
    }else{
      sqlite3_int64 iVar;
      p += sqlite3Fts3GetVarint(p, &iVar);
      *piDocid += ((bDescIdx ? -1 : 1) * iVar);
    }
................................................................................

  iDocid = pExpr->iDocid;
  pIter = pPhrase->doclist.pList;
  if( iDocid!=pCsr->iPrevId || pExpr->bEof ){
    int rc = SQLITE_OK;
    int bDescDoclist = pTab->bDescIdx;      /* For DOCID_CMP macro */
    int bOr = 0;
    u8 bEof = 0;
    u8 bTreeEof = 0;
    Fts3Expr *p;                  /* Used to iterate from pExpr to root */
    Fts3Expr *pNear;              /* Most senior NEAR ancestor (or pExpr) */


    /* Check if this phrase descends from an OR expression node. If not, 
    ** return NULL. Otherwise, the entry that corresponds to docid 
    ** pCsr->iPrevId may lie earlier in the doclist buffer. Or, if the
    ** tree that the node is part of has been marked as EOF, but the node
    ** itself is not EOF, then it may point to an earlier entry. */
    pNear = pExpr;
................................................................................
    if( bTreeEof ){
      while( rc==SQLITE_OK && !pNear->bEof ){
        fts3EvalNextRow(pCsr, pNear, &rc);
      }
    }
    if( rc!=SQLITE_OK ) return rc;











    pIter = pPhrase->pOrPoslist;
    iDocid = pPhrase->iOrDocid;
    if( pCsr->bDesc==bDescDoclist ){
      bEof = !pPhrase->doclist.nAll ||
                 (pIter >= (pPhrase->doclist.aAll + pPhrase->doclist.nAll));
      while( (pIter==0 || DOCID_CMP(iDocid, pCsr->iPrevId)<0 ) && bEof==0 ){
        sqlite3Fts3DoclistNext(
            bDescDoclist, pPhrase->doclist.aAll, pPhrase->doclist.nAll, 

            &pIter, &iDocid, &bEof
        );
      }
    }else{
      bEof = !pPhrase->doclist.nAll || (pIter && pIter<=pPhrase->doclist.aAll);
      while( (pIter==0 || DOCID_CMP(iDocid, pCsr->iPrevId)>0 ) && bEof==0 ){
        int dummy;
        sqlite3Fts3DoclistPrev(
            bDescDoclist, pPhrase->doclist.aAll, pPhrase->doclist.nAll, 

            &pIter, &iDocid, &dummy, &bEof
        );
      }
    }
    pPhrase->pOrPoslist = pIter;
    pPhrase->iOrDocid = iDocid;


    if( bEof || iDocid!=pCsr->iPrevId ) pIter = 0;






  }
  if( pIter==0 ) return SQLITE_OK;

  if( *pIter==0x01 ){
    pIter++;
    pIter += fts3GetVarint32(pIter, &iThis);
  }else{

  assert( !p || (p>=aDoclist && p<=&aDoclist[nDoclist]) );

  if( p==0 ){
    p = aDoclist;
    p += sqlite3Fts3GetVarint(p, piDocid);
  }else{
    fts3PoslistCopy(0, &p);
    while( p<&aDoclist[nDoclist] && *p==0 ) p++; 
    if( p>=&aDoclist[nDoclist] ){
      *pbEof = 1;
    }else{
      sqlite3_int64 iVar;
      p += sqlite3Fts3GetVarint(p, &iVar);
      *piDocid += ((bDescIdx ? -1 : 1) * iVar);
    }
................................................................................

  iDocid = pExpr->iDocid;
  pIter = pPhrase->doclist.pList;
  if( iDocid!=pCsr->iPrevId || pExpr->bEof ){
    int rc = SQLITE_OK;
    int bDescDoclist = pTab->bDescIdx;      /* For DOCID_CMP macro */
    int bOr = 0;

    u8 bTreeEof = 0;
    Fts3Expr *p;                  /* Used to iterate from pExpr to root */
    Fts3Expr *pNear;              /* Most senior NEAR ancestor (or pExpr) */
    int bMatch;

    /* Check if this phrase descends from an OR expression node. If not, 
    ** return NULL. Otherwise, the entry that corresponds to docid 
    ** pCsr->iPrevId may lie earlier in the doclist buffer. Or, if the
    ** tree that the node is part of has been marked as EOF, but the node
    ** itself is not EOF, then it may point to an earlier entry. */
    pNear = pExpr;
................................................................................
    if( bTreeEof ){
      while( rc==SQLITE_OK && !pNear->bEof ){
        fts3EvalNextRow(pCsr, pNear, &rc);
      }
    }
    if( rc!=SQLITE_OK ) return rc;

    bMatch = 1;
    for(p=pNear; p; p=p->pLeft){
      u8 bEof = 0;
      Fts3Expr *pTest = p;
      Fts3Phrase *pPh;
      assert( pTest->eType==FTSQUERY_NEAR || pTest->eType==FTSQUERY_PHRASE );
      if( pTest->eType==FTSQUERY_NEAR ) pTest = pTest->pRight;
      assert( pTest->eType==FTSQUERY_PHRASE );
      pPh = pTest->pPhrase;

      pIter = pPh->pOrPoslist;
      iDocid = pPh->iOrDocid;
      if( pCsr->bDesc==bDescDoclist ){
        bEof = !pPh->doclist.nAll ||
          (pIter >= (pPh->doclist.aAll + pPh->doclist.nAll));
        while( (pIter==0 || DOCID_CMP(iDocid, pCsr->iPrevId)<0 ) && bEof==0 ){
          sqlite3Fts3DoclistNext(

              bDescDoclist, pPh->doclist.aAll, pPh->doclist.nAll, 
              &pIter, &iDocid, &bEof
          );
        }
      }else{
        bEof = !pPh->doclist.nAll || (pIter && pIter<=pPh->doclist.aAll);
        while( (pIter==0 || DOCID_CMP(iDocid, pCsr->iPrevId)>0 ) && bEof==0 ){
          int dummy;
          sqlite3Fts3DoclistPrev(

              bDescDoclist, pPh->doclist.aAll, pPh->doclist.nAll, 
              &pIter, &iDocid, &dummy, &bEof
              );
        }
      }
      pPh->pOrPoslist = pIter;
      pPh->iOrDocid = iDocid;
      if( bEof || iDocid!=pCsr->iPrevId ) bMatch = 0;
    }


    if( bMatch ){
      pIter = pPhrase->pOrPoslist;
    }else{
      pIter = 0;
    }
  }
  if( pIter==0 ) return SQLITE_OK;

  if( *pIter==0x01 ){
    pIter++;
    pIter += fts3GetVarint32(pIter, &iThis);
  }else{

  array set M [get_struct_members $data]
  
  # Initialize global list D as a map from section name to documentation
  # text. Most (all?) section names are structure member names.
  #
  set D [get_struct_docs $data [array names M]]
  

  foreach {sub docs} $D {
    if {[info exists M($sub)]} {
      set hdr $M($sub)
      set link " id=$sub"
    } else {
      set link ""
    }

    output "<hr color=#eeeee style=\"margin:1em 8.4ex 0 8.4ex;\"$link>"
    set style "padding-left:6ex;font-size:1.4em;display:block"
    output "<h style=\"$style\"><pre>$hdr</pre></h>"
  





    set mode ""
    set bEmpty 1

    foreach line [split [string trim $docs] "\n"] {
      if {[string trim $line]==""} {
        if {$mode != ""} {output "</$mode>"}
        set mode ""
      } elseif {$mode == ""} {
        if {[regexp {^     } $line]} {
          set mode codeblock
        } else {
          set mode p
        }
        output "<$mode>"

      }
      output $line
    }
    if {$mode != ""} {output "</$mode>"}

  }

}

proc get_fts5_struct {data start end} {
  set res ""
  set bOut 0
  foreach line [split $data "\n"] {
    if {$bOut==0} {

  array set M [get_struct_members $data]
  
  # Initialize global list D as a map from section name to documentation
  # text. Most (all?) section names are structure member names.
  #
  set D [get_struct_docs $data [array names M]]
  
  output "<dl>"
  foreach {sub docs} $D {
    if {[info exists M($sub)]} {
      set hdr $M($sub)
      set link " id=$sub"
    } else {
      set link ""
    }

    #output "<hr color=#eeeee style=\"margin:1em 8.4ex 0 8.4ex;\"$link>"
    #set style "padding-left:6ex;font-size:1.4em;display:block"
    #output "<h style=\"$style\"><pre>$hdr</pre></h>"

    regsub -line {^  *[)]} $hdr ")" hdr
    output "<dt style=\"white-space:pre;font-family:monospace;font-size:120%\""
    output "$link>"
    output "<b>$hdr</b></dt><dd>"
  
    set mode ""

    set margin " style=margin-top:0.1em"
    foreach line [split [string trim $docs] "\n"] {
      if {[string trim $line]==""} {
        if {$mode != ""} {output "</$mode>"}
        set mode ""
      } elseif {$mode == ""} {
        if {[regexp {^     } $line]} {
          set mode codeblock
        } else {
          set mode p
        }
        output "<$mode$margin>"
        set margin ""
      }
      output $line
    }
    if {$mode != ""} {output "</$mode>"}
    output "</dd>"
  }
  output "</dl>"
}

proc get_fts5_struct {data start end} {
  set res ""
  set bOut 0
  foreach line [split $data "\n"] {
    if {$bOut==0} {

#define ArraySize(x) (sizeof(x) / sizeof(x[0]))

#define testcase(x)
#define ALWAYS(x) 1
#define NEVER(x) 0

#define MIN(x,y) (((x) < (y)) ? (x) : (y))








#endif


/*
** Maximum number of prefix indexes on single FTS5 table. This must be
** less than 32. If it is set to anything large than that, an #error

#define ArraySize(x) (sizeof(x) / sizeof(x[0]))

#define testcase(x)
#define ALWAYS(x) 1
#define NEVER(x) 0

#define MIN(x,y) (((x) < (y)) ? (x) : (y))
#define MAX(x,y) (((x) > (y)) ? (x) : (y))

/*
** Constants for the largest and smallest possible 64-bit signed integers.
*/
# define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
# define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)

#endif


/*
** Maximum number of prefix indexes on single FTS5 table. This must be
** less than 32. If it is set to anything large than that, an #error

typedef struct Fts5BtreeIter Fts5BtreeIter;
typedef struct Fts5BtreeIterLevel Fts5BtreeIterLevel;
typedef struct Fts5Data Fts5Data;
typedef struct Fts5DlidxIter Fts5DlidxIter;
typedef struct Fts5DlidxLvl Fts5DlidxLvl;
typedef struct Fts5DlidxWriter Fts5DlidxWriter;
typedef struct Fts5MultiSegIter Fts5MultiSegIter;
typedef struct Fts5NodeIter Fts5NodeIter;
typedef struct Fts5PageWriter Fts5PageWriter;
typedef struct Fts5SegIter Fts5SegIter;
typedef struct Fts5DoclistIter Fts5DoclistIter;
typedef struct Fts5SegWriter Fts5SegWriter;
typedef struct Fts5Structure Fts5Structure;
typedef struct Fts5StructureLevel Fts5StructureLevel;
................................................................................

  /* Output variables. aPoslist==0 at EOF */
  i64 iRowid;
  u8 *aPoslist;
  int nPoslist;
};

/*
** Each iterator used by external modules is an instance of this type.
*/
struct Fts5IndexIter {
  Fts5Index *pIndex;
  Fts5Structure *pStruct;
  Fts5MultiSegIter *pMulti;
  Fts5Buffer poslist;             /* Buffer containing current poslist */
};

/*
** The contents of the "structure" record for each index are represented
** using an Fts5Structure record in memory. Which uses instances of the 
** other Fts5StructureXXX types as components.
*/
struct Fts5StructureSegment {
  int iSegid;                     /* Segment id */
................................................................................
};
struct Fts5StructureLevel {
  int nMerge;                     /* Number of segments in incr-merge */
  int nSeg;                       /* Total number of segments on level */
  Fts5StructureSegment *aSeg;     /* Array of segments. aSeg[0] is oldest. */
};
struct Fts5Structure {

  u64 nWriteCounter;              /* Total leaves written to level 0 */
  int nSegment;                   /* Total segments in this structure */
  int nLevel;                     /* Number of levels in this index */
  Fts5StructureLevel aLevel[0];   /* Array of nLevel level objects */
};

/*
................................................................................

typedef struct Fts5CResult Fts5CResult;
struct Fts5CResult {
  u16 iFirst;                     /* aSeg[] index of firstest iterator */
  u8 bTermEq;                     /* True if the terms are equal */
};

struct Fts5MultiSegIter {
  int nSeg;                       /* Size of aSeg[] array */
  int bRev;                       /* True to iterate in reverse order */
  int bSkipEmpty;                 /* True to skip deleted entries */
  Fts5SegIter *aSeg;              /* Array of segment iterators */
  Fts5CResult *aFirst;            /* Current merge state (see above) */
};

/*
** Object for iterating through a single segment, visiting each term/docid
** pair in the segment.
**
** pSeg:
**   The segment to iterate through.
**
................................................................................
  int nPos;                       /* Number of bytes in current position list */
  int bDel;                       /* True if the delete flag is set */
};

#define FTS5_SEGITER_ONETERM 0x01
#define FTS5_SEGITER_REVERSE 0x02























/*
** Object for iterating through the conents of a single internal node in 
** memory.
*/
struct Fts5NodeIter {
  /* Internal. Set and managed by fts5NodeIterXXX() functions. Except, 
................................................................................
  Fts5Buffer term;                /* Current term */
  int iLeaf;                      /* Leaf containing terms >= current term */
  int nEmpty;                     /* Number of "empty" leaves following iLeaf */
  int bEof;                       /* Set to true at EOF */
  int bDlidx;                     /* True if there exists a dlidx */
};

















static void fts5PutU16(u8 *aOut, u16 iVal){
  aOut[0] = (iVal>>8);
  aOut[1] = (iVal&0xFF);
}

static u16 fts5GetU16(const u8 *aIn){
................................................................................
    ** backing store corruption.  */
    if( rc==SQLITE_ERROR ) rc = FTS5_CORRUPT;

    if( rc==SQLITE_OK ){
      u8 *aOut;                   /* Read blob data into this buffer */
      int nByte = sqlite3_blob_bytes(p->pReader);
      if( pBuf ){
        fts5BufferZero(pBuf);
        fts5BufferGrow(&rc, pBuf, nByte);
        aOut = pBuf->p;
        pBuf->n = nByte;


      }else{
        int nSpace = nByte + FTS5_DATA_ZERO_PADDING;
        pRet = (Fts5Data*)sqlite3Fts5MallocZero(&rc, nSpace+sizeof(Fts5Data));
        if( pRet ){
          pRet->n = nByte;
          aOut = pRet->p = (u8*)&pRet[1];


        }
      }

      if( rc==SQLITE_OK ){
        rc = sqlite3_blob_read(p->pReader, aOut, nByte, 0);
      }
      if( rc!=SQLITE_OK ){
................................................................................
}

/*
** Release a reference to an Fts5Structure object returned by an earlier 
** call to fts5StructureRead() or fts5StructureDecode().
*/
static void fts5StructureRelease(Fts5Structure *pStruct){
  if( pStruct ){
    int i;

    for(i=0; i<pStruct->nLevel; i++){
      sqlite3_free(pStruct->aLevel[i].aSeg);
    }
    sqlite3_free(pStruct);
  }
}





/*
** Deserialize and return the structure record currently stored in serialized
** form within buffer pData/nData.
**
** The Fts5Structure.aLevel[] and each Fts5StructureLevel.aSeg[] array
** are over-allocated by one slot. This allows the structure contents
................................................................................
  nByte = (
      sizeof(Fts5Structure) +                    /* Main structure */
      sizeof(Fts5StructureLevel) * (nLevel)      /* aLevel[] array */
  );
  pRet = (Fts5Structure*)sqlite3Fts5MallocZero(&rc, nByte);

  if( pRet ){

    pRet->nLevel = nLevel;
    pRet->nSegment = nSegment;
    i += sqlite3Fts5GetVarint(&pData[i], &pRet->nWriteCounter);

    for(iLvl=0; rc==SQLITE_OK && iLvl<nLevel; iLvl++){
      Fts5StructureLevel *pLvl = &pRet->aLevel[iLvl];
      int nTotal;
................................................................................
** If an error occurs, NULL is returned and an error code left in the
** Fts5Index handle. If an error has already occurred when this function
** is called, it is a no-op.
*/
static Fts5Structure *fts5StructureRead(Fts5Index *p){
  Fts5Config *pConfig = p->pConfig;
  Fts5Structure *pRet = 0;        /* Object to return */
  Fts5Data *pData;                /* %_data entry containing structure record */
  int iCookie;                    /* Configuration cookie */


  pData = fts5DataRead(p, FTS5_STRUCTURE_ROWID);
  if( !pData ) return 0;


  p->rc = fts5StructureDecode(pData->p, pData->n, &iCookie, &pRet);

  if( p->rc==SQLITE_OK && pConfig->iCookie!=iCookie ){
    p->rc = sqlite3Fts5ConfigLoad(pConfig, iCookie);
  }

  fts5DataRelease(pData);
  if( p->rc!=SQLITE_OK ){
    fts5StructureRelease(pRet);
    pRet = 0;
  }
  return pRet;
}

................................................................................
      p->rc = FTS5_CORRUPT;
    }else{
      const u8 *a = &pIter->pLeaf->p[iOff];
      pIter->iLeafOffset += fts5GetPoslistSize(a, &pIter->nPos, &pIter->bDel);
    }
  }
}


















/*
** Fts5SegIter.iLeafOffset currently points to the first byte of the 
** "nSuffix" field of a term. Function parameter nKeep contains the value
** of the "nPrefix" field (if there was one - it is passed 0 if this is
** the first term in the segment).
**
................................................................................

  iOff += fts5GetVarint32(&a[iOff], nNew);
  pIter->term.n = nKeep;
  fts5BufferAppendBlob(&p->rc, &pIter->term, nNew, &a[iOff]);
  iOff += nNew;
  pIter->iTermLeafOffset = iOff;
  pIter->iTermLeafPgno = pIter->iLeafPgno;
  if( iOff>=pIter->pLeaf->n ){
    fts5SegIterNextPage(p, pIter);
    if( pIter->pLeaf==0 ){
      if( p->rc==SQLITE_OK ) p->rc = FTS5_CORRUPT;
      return;
    }
    iOff = 4;
    a = pIter->pLeaf->p;
  }
  iOff += sqlite3Fts5GetVarint(&a[iOff], (u64*)&pIter->iRowid);
  pIter->iLeafOffset = iOff;

}

/*
** Initialize the iterator object pIter to iterate through the entries in
** segment pSeg. The iterator is left pointing to the first entry when 
** this function returns.
**
................................................................................
}

/*
** Return true if the iterator passed as the second argument currently
** points to a delete marker. A delete marker is an entry with a 0 byte
** position-list.
*/
static int fts5MultiIterIsEmpty(Fts5Index *p, Fts5MultiSegIter *pIter){
  Fts5SegIter *pSeg = &pIter->aSeg[pIter->aFirst[1].iFirst];
  return (p->rc==SQLITE_OK && pSeg->pLeaf && pSeg->nPos==0);
}

/*
** Advance iterator pIter to the next entry. 
**
................................................................................
      iOff += fts5GetPoslistSize(&pLeaf->p[iOff], &nPos, &bDummy);
      iOff += nPos;
    }
  }

  pIter->pDlidx = fts5DlidxIterInit(p, bRev, iSeg, pIter->iTermLeafPgno);
}

































/*
































































































































































































































** Initialize the object pIter to point to term pTerm/nTerm within segment
** pSeg. If there is no such term in the index, the iterator is set to EOF.
**
** If an error occurs, Fts5Index.rc is set to an appropriate error code. If 
** an error has already occurred when this function is called, it is a no-op.
*/
static void fts5SegIterSeekInit(
  Fts5Index *p,                   /* FTS5 backend */

  const u8 *pTerm, int nTerm,     /* Term to seek to */
  int flags,                      /* Mask of FTS5INDEX_XXX flags */
  Fts5StructureSegment *pSeg,     /* Description of segment */
  Fts5SegIter *pIter              /* Object to populate */
){
  int iPg = 1;
  int h;
  int bGe = (flags & FTS5INDEX_QUERY_SCAN);
  int bDlidx = 0;                 /* True if there is a doclist-index */
  Fts5Data *pLeaf;




  assert( bGe==0 || (flags & FTS5INDEX_QUERY_DESC)==0 );
  assert( pTerm && nTerm );
  memset(pIter, 0, sizeof(*pIter));
  pIter->pSeg = pSeg;

  /* This block sets stack variable iPg to the leaf page number that may
  ** contain term (pTerm/nTerm), if it is present in the segment. */
  for(h=pSeg->nHeight-1; h>0; h--){
    Fts5NodeIter node;              /* For iterating through internal nodes */
    i64 iRowid = FTS5_SEGMENT_ROWID(pSeg->iSegid, h, iPg);
    Fts5Data *pNode = fts5DataRead(p, iRowid);

    if( pNode==0 ) break;

    fts5NodeIterInit(pNode->p, pNode->n, &node);
    assert( node.term.n==0 );

    iPg = node.iChild;
    bDlidx = node.bDlidx;
    for(fts5NodeIterNext(&p->rc, &node);
        node.aData && fts5BufferCompareBlob(&node.term, pTerm, nTerm)<=0;
        fts5NodeIterNext(&p->rc, &node)
    ){
      iPg = node.iChild;
      bDlidx = node.bDlidx;
    }
    fts5NodeIterFree(&node);
    fts5DataRelease(pNode);

  }

  if( iPg<pSeg->pgnoFirst ){
    iPg = pSeg->pgnoFirst;
    bDlidx = 0;
  }

  pIter->iLeafPgno = iPg - 1;
  fts5SegIterNextPage(p, pIter);

  if( (pLeaf = pIter->pLeaf) ){
    int res;
    pIter->iLeafOffset = fts5GetU16(&pLeaf->p[2]);
    if( pIter->iLeafOffset<4 || pIter->iLeafOffset>=pLeaf->n ){
      p->rc = FTS5_CORRUPT;
    }else{
      fts5SegIterLoadTerm(p, pIter, 0);
      fts5SegIterLoadNPos(p, pIter);
      do {
        res = fts5BufferCompareBlob(&pIter->term, pTerm, nTerm);
        if( res>=0 ) break;
        fts5SegIterNext(p, pIter, 0);
      }while( pIter->pLeaf && p->rc==SQLITE_OK );

      if( bGe==0 && res ){
        /* Set iterator to point to EOF */
        fts5DataRelease(pIter->pLeaf);
        pIter->pLeaf = 0;
      }
    }

  }

  if( p->rc==SQLITE_OK && bGe==0 ){
    pIter->flags |= FTS5_SEGITER_ONETERM;
    if( pIter->pLeaf ){
      if( flags & FTS5INDEX_QUERY_DESC ){
        pIter->flags |= FTS5_SEGITER_REVERSE;
................................................................................
        fts5SegIterLoadDlidx(p, pIter);
      }
      if( flags & FTS5INDEX_QUERY_DESC ){
        fts5SegIterReverse(p, pIter);
      }
    }
  }














}

/*
** Initialize the object pIter to point to term pTerm/nTerm within the
** in-memory hash table. If there is no such term in the hash-table, the 
** iterator is set to EOF.
**
................................................................................
/*
** This function is used as part of the big assert() procedure implemented by
** fts5AssertMultiIterSetup(). It ensures that the result currently stored
** in *pRes is the correct result of comparing the current positions of the
** two iterators.
*/
static void fts5AssertComparisonResult(
  Fts5MultiSegIter *pIter, 
  Fts5SegIter *p1,
  Fts5SegIter *p2,
  Fts5CResult *pRes
){
  int i1 = p1 - pIter->aSeg;
  int i2 = p2 - pIter->aSeg;

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

/*
** This function is a no-op unless SQLITE_DEBUG is defined when this module
** is compiled. In that case, this function is essentially an assert() 
** statement used to verify that the contents of the pIter->aFirst[] array
** are correct.
*/
static void fts5AssertMultiIterSetup(Fts5Index *p, Fts5MultiSegIter *pIter){
  if( p->rc==SQLITE_OK ){

    int i;














    for(i=0; i<pIter->nSeg; i+=2){
      Fts5SegIter *p1 = &pIter->aSeg[i];
      Fts5SegIter *p2 = &pIter->aSeg[i+1];
      Fts5CResult *pRes = &pIter->aFirst[(pIter->nSeg + i) / 2];
      fts5AssertComparisonResult(pIter, p1, p2, pRes);
    }

    for(i=1; i<(pIter->nSeg / 2); i+=2){
      Fts5CResult *pRes = &pIter->aFirst[i];
      Fts5SegIter *p1 = &pIter->aSeg[ pIter->aFirst[i*2].iFirst ];
      Fts5SegIter *p2 = &pIter->aSeg[ pIter->aFirst[i*2+1].iFirst ];


      fts5AssertComparisonResult(pIter, p1, p2, pRes);
    }
  }
}
#else
# define fts5AssertMultiIterSetup(x,y)
#endif
................................................................................
** Do the comparison necessary to populate pIter->aFirst[iOut].
**
** If the returned value is non-zero, then it is the index of an entry
** in the pIter->aSeg[] array that is (a) not at EOF, and (b) pointing
** to a key that is a duplicate of another, higher priority, 
** segment-iterator in the pSeg->aSeg[] array.
*/
static int fts5MultiIterDoCompare(Fts5MultiSegIter *pIter, int iOut){
  int i1;                         /* Index of left-hand Fts5SegIter */
  int i2;                         /* Index of right-hand Fts5SegIter */
  int iRes;
  Fts5SegIter *p1;                /* Left-hand Fts5SegIter */
  Fts5SegIter *p2;                /* Right-hand Fts5SegIter */
  Fts5CResult *pRes = &pIter->aFirst[iOut];

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


/*
** Free the iterator object passed as the second argument.
*/
static void fts5MultiIterFree(Fts5Index *p, Fts5MultiSegIter *pIter){
  if( pIter ){
    int i;
    for(i=0; i<pIter->nSeg; i++){
      fts5SegIterClear(&pIter->aSeg[i]);
    }


    sqlite3_free(pIter);
  }
}

static void fts5MultiIterAdvanced(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5MultiSegIter *pIter,        /* Iterator to update aFirst[] array for */
  int iChanged,                   /* Index of sub-iterator just advanced */
  int iMinset                     /* Minimum entry in aFirst[] to set */
){
  int i;
  for(i=(pIter->nSeg+iChanged)/2; i>=iMinset && p->rc==SQLITE_OK; i=i/2){
    int iEq;
    if( (iEq = fts5MultiIterDoCompare(pIter, i)) ){
      fts5SegIterNext(p, &pIter->aSeg[iEq], 0);
      i = pIter->nSeg + iEq;
    }
  }
}











static int fts5MultiIterAdvanceRowid(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5MultiSegIter *pIter,        /* Iterator to update aFirst[] array for */
  int iChanged                    /* Index of sub-iterator just advanced */
){
  int i;
  Fts5SegIter *pNew = &pIter->aSeg[iChanged];
  Fts5SegIter *pOther = &pIter->aSeg[iChanged ^ 0x0001];







  for(i=(pIter->nSeg+iChanged)/2; p->rc==SQLITE_OK; i=i/2){
    Fts5CResult *pRes = &pIter->aFirst[i];

    assert( pNew->pLeaf );
    assert( pRes->bTermEq==0 || pOther->pLeaf );
    
    if( pRes->bTermEq ){
      if( pNew->iRowid==pOther->iRowid ){
        return 1;
      }else if( (pOther->iRowid>pNew->iRowid)==pIter->bRev ){

        pNew = pOther;


      }
    }
    pRes->iFirst = (pNew - pIter->aSeg);
    if( i==1 ) break;

    pOther = &pIter->aSeg[ pIter->aFirst[i ^ 0x0001].iFirst ];
  }


  return 0;
}










/*
** Move the iterator to the next entry. 
**
** If an error occurs, an error code is left in Fts5Index.rc. It is not 
** considered an error if the iterator reaches EOF, or if it is already at 
** EOF when this function is called.
*/
static void fts5MultiIterNext(
  Fts5Index *p, 
  Fts5MultiSegIter *pIter,
  int bFrom,                      /* True if argument iFrom is valid */
  i64 iFrom                       /* Advance at least as far as this */
){
  if( p->rc==SQLITE_OK ){
    int bUseFrom = bFrom;
    do {
      int iFirst = pIter->aFirst[1].iFirst;
................................................................................
        fts5SegIterNext(p, pSeg, &bNewTerm);
      }

      if( pSeg->pLeaf==0 || bNewTerm 
       || fts5MultiIterAdvanceRowid(p, pIter, iFirst)
      ){
        fts5MultiIterAdvanced(p, pIter, iFirst, 1);

      }
      fts5AssertMultiIterSetup(p, pIter);

      bUseFrom = 0;
    }while( pIter->bSkipEmpty && fts5MultiIterIsEmpty(p, pIter) );
  }
}

static Fts5MultiSegIter *fts5MultiIterAlloc(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  int nSeg
){
  Fts5MultiSegIter *pNew;
  int nSlot;                      /* Power of two >= nSeg */

  for(nSlot=2; nSlot<nSeg; nSlot=nSlot*2);
  pNew = fts5IdxMalloc(p, 
      sizeof(Fts5MultiSegIter) +          /* pNew */
      sizeof(Fts5SegIter) * nSlot +       /* pNew->aSeg[] */
      sizeof(Fts5CResult) * nSlot         /* pNew->aFirst[] */
  );
  if( pNew ){
    pNew->nSeg = nSlot;
    pNew->aSeg = (Fts5SegIter*)&pNew[1];
    pNew->aFirst = (Fts5CResult*)&pNew->aSeg[nSlot];

  }
  return pNew;
}

/*
** Allocate a new Fts5MultiSegIter object.
**
** The new object will be used to iterate through data in structure pStruct.
** If iLevel is -ve, then all data in all segments is merged. Or, if iLevel
** is zero or greater, data from the first nSegment segments on level iLevel
** is merged.
**
** The iterator initially points to the first term/rowid entry in the 
................................................................................
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5Structure *pStruct,         /* Structure of specific index */
  int bSkipEmpty,                 /* True to ignore delete-keys */
  int flags,                      /* FTS5INDEX_QUERY_XXX flags */
  const u8 *pTerm, int nTerm,     /* Term to seek to (or NULL/0) */
  int iLevel,                     /* Level to iterate (-1 for all) */
  int nSegment,                   /* Number of segments to merge (iLevel>=0) */
  Fts5MultiSegIter **ppOut        /* New object */
){
  int nSeg = 0;                   /* Number of segment-iters in use */
  int iIter = 0;                  /* */
  int iSeg;                       /* Used to iterate through segments */

  Fts5StructureLevel *pLvl;
  Fts5MultiSegIter *pNew;

  assert( (pTerm==0 && nTerm==0) || iLevel<0 );

  /* Allocate space for the new multi-seg-iterator. */
  if( p->rc==SQLITE_OK ){
    if( iLevel<0 ){
      assert( pStruct->nSegment==fts5StructureCountSegments(pStruct) );
................................................................................
      nSeg = MIN(pStruct->aLevel[iLevel].nSeg, nSegment);
    }
  }
  *ppOut = pNew = fts5MultiIterAlloc(p, nSeg);
  if( pNew==0 ) return;
  pNew->bRev = (0!=(flags & FTS5INDEX_QUERY_DESC));
  pNew->bSkipEmpty = bSkipEmpty;



  /* Initialize each of the component segment iterators. */
  if( iLevel<0 ){
    Fts5StructureLevel *pEnd = &pStruct->aLevel[pStruct->nLevel];
    if( p->pHash ){
      /* Add a segment iterator for the current contents of the hash table. */
      Fts5SegIter *pIter = &pNew->aSeg[iIter++];
................................................................................
    for(pLvl=&pStruct->aLevel[0]; pLvl<pEnd; pLvl++){
      for(iSeg=pLvl->nSeg-1; iSeg>=0; iSeg--){
        Fts5StructureSegment *pSeg = &pLvl->aSeg[iSeg];
        Fts5SegIter *pIter = &pNew->aSeg[iIter++];
        if( pTerm==0 ){
          fts5SegIterInit(p, pSeg, pIter);
        }else{
          fts5SegIterSeekInit(p, pTerm, nTerm, flags, pSeg, pIter);
        }
      }
    }
  }else{
    pLvl = &pStruct->aLevel[iLevel];
    for(iSeg=nSeg-1; iSeg>=0; iSeg--){
      fts5SegIterInit(p, &pLvl->aSeg[iSeg], &pNew->aSeg[iIter++]);
................................................................................
    for(iIter=pNew->nSeg-1; iIter>0; iIter--){
      int iEq;
      if( (iEq = fts5MultiIterDoCompare(pNew, iIter)) ){
        fts5SegIterNext(p, &pNew->aSeg[iEq], 0);
        fts5MultiIterAdvanced(p, pNew, iEq, iIter);
      }
    }

    fts5AssertMultiIterSetup(p, pNew);

    if( pNew->bSkipEmpty && fts5MultiIterIsEmpty(p, pNew) ){
      fts5MultiIterNext(p, pNew, 0, 0);
    }
  }else{
    fts5MultiIterFree(p, pNew);
    *ppOut = 0;
  }

}

/*
** Create an Fts5MultiSegIter that iterates through the doclist provided
** as the second argument.
*/
static void fts5MultiIterNew2(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5Data *pData,                /* Doclist to iterate through */
  int bDesc,                      /* True for descending rowid order */
  Fts5MultiSegIter **ppOut        /* New object */
){
  Fts5MultiSegIter *pNew;
  pNew = fts5MultiIterAlloc(p, 2);
  if( pNew ){
    Fts5SegIter *pIter = &pNew->aSeg[1];

    pIter->flags = FTS5_SEGITER_ONETERM;
    if( pData->n>0 ){
      pIter->pLeaf = pData;
................................................................................
        pNew->bRev = 1;
        pIter->flags |= FTS5_SEGITER_REVERSE;
        fts5SegIterReverseInitPage(p, pIter);
      }else{
        fts5SegIterLoadNPos(p, pIter);
      }
      pData = 0;


    }

    *ppOut = pNew;
  }

  fts5DataRelease(pData);
}

/*
** Return true if the iterator is at EOF or if an error has occurred. 
** False otherwise.
*/
static int fts5MultiIterEof(Fts5Index *p, Fts5MultiSegIter *pIter){

  return (p->rc || pIter->aSeg[ pIter->aFirst[1].iFirst ].pLeaf==0);


}

/*
** Return the rowid of the entry that the iterator currently points
** to. If the iterator points to EOF when this function is called the
** results are undefined.
*/
static i64 fts5MultiIterRowid(Fts5MultiSegIter *pIter){
  assert( pIter->aSeg[ pIter->aFirst[1].iFirst ].pLeaf );
  return pIter->aSeg[ pIter->aFirst[1].iFirst ].iRowid;
}

/*
** Move the iterator to the next entry at or following iMatch.
*/
static void fts5MultiIterNextFrom(
  Fts5Index *p, 
  Fts5MultiSegIter *pIter, 
  i64 iMatch
){
  while( 1 ){
    i64 iRowid;
    fts5MultiIterNext(p, pIter, 1, iMatch);
    if( fts5MultiIterEof(p, pIter) ) break;
    iRowid = fts5MultiIterRowid(pIter);
................................................................................
  }
}

/*
** Return a pointer to a buffer containing the term associated with the 
** entry that the iterator currently points to.
*/
static const u8 *fts5MultiIterTerm(Fts5MultiSegIter *pIter, int *pn){
  Fts5SegIter *p = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
  *pn = p->term.n;
  return p->term.p;
}

static void fts5ChunkIterate(
  Fts5Index *p,                   /* Index object */
................................................................................
}

/*
** Iterator pIter was used to iterate through the input segments of on an
** incremental merge operation. This function is called if the incremental
** merge step has finished but the input has not been completely exhausted.
*/
static void fts5TrimSegments(Fts5Index *p, Fts5MultiSegIter *pIter){
  int i;
  Fts5Buffer buf;
  memset(&buf, 0, sizeof(Fts5Buffer));
  for(i=0; i<pIter->nSeg; i++){
    Fts5SegIter *pSeg = &pIter->aSeg[i];
    if( pSeg->pSeg==0 ){
      /* no-op */
................................................................................
  Fts5Structure **ppStruct,       /* IN/OUT: Stucture of index */
  int iLvl,                       /* Level to read input from */
  int *pnRem                      /* Write up to this many output leaves */
){
  Fts5Structure *pStruct = *ppStruct;
  Fts5StructureLevel *pLvl = &pStruct->aLevel[iLvl];
  Fts5StructureLevel *pLvlOut;
  Fts5MultiSegIter *pIter = 0;    /* Iterator to read input data */
  int nRem = pnRem ? *pnRem : 0;  /* Output leaf pages left to write */
  int nInput;                     /* Number of input segments */
  Fts5SegWriter writer;           /* Writer object */
  Fts5StructureSegment *pSeg;     /* Output segment */
  Fts5Buffer term;
  int bRequireDoclistTerm = 0;    /* Doclist terminator (0x00) required */
  int bOldest;                    /* True if the output segment is the oldest */
................................................................................
      pNew = (Fts5Structure*)sqlite3Fts5MallocZero(&p->rc, nByte);
    }
  }
  if( pNew ){
    Fts5StructureLevel *pLvl;
    int nByte = nSeg * sizeof(Fts5StructureSegment);
    pNew->nLevel = pStruct->nLevel+1;

    pNew->nWriteCounter = pStruct->nWriteCounter;
    pLvl = &pNew->aLevel[pStruct->nLevel];
    pLvl->aSeg = (Fts5StructureSegment*)sqlite3Fts5MallocZero(&p->rc, nByte);
    if( pLvl->aSeg ){
      int iLvl, iSeg;
      int iSegOut = 0;
      for(iLvl=0; iLvl<pStruct->nLevel; iLvl++){
................................................................................
** currently points to to buffer pBuf.
**
** If an error occurs, an error code is left in p->rc. It is assumed
** no error has already occurred when this function is called.
*/
static void fts5MultiIterPoslist(
  Fts5Index *p,
  Fts5MultiSegIter *pMulti,
  int bSz,                        /* Append a size field before the data */
  Fts5Buffer *pBuf
){
  if( p->rc==SQLITE_OK ){
    Fts5SegIter *pSeg = &pMulti->aSeg[ pMulti->aFirst[1].iFirst ];
    assert( fts5MultiIterEof(p, pMulti)==0 );

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

static void fts5SetupPrefixIter(
  Fts5Index *p,                   /* Index to read from */
  int bDesc,                      /* True for "ORDER BY rowid DESC" */
  const u8 *pToken,               /* Buffer containing prefix to match */
  int nToken,                     /* Size of buffer pToken in bytes */
  Fts5IndexIter *pIter            /* Populate this object */
){
  Fts5Structure *pStruct;
  Fts5Buffer *aBuf;
  const int nBuf = 32;

  aBuf = (Fts5Buffer*)fts5IdxMalloc(p, sizeof(Fts5Buffer)*nBuf);
  pStruct = fts5StructureRead(p);

  if( aBuf && pStruct ){
    const int flags = FTS5INDEX_QUERY_SCAN;
    int i;
    i64 iLastRowid = 0;
    Fts5MultiSegIter *p1 = 0;     /* Iterator used to gather data from index */
    Fts5Data *pData;
    Fts5Buffer doclist;

    memset(&doclist, 0, sizeof(doclist));
    for(fts5MultiIterNew(p, pStruct, 1, flags, pToken, nToken, -1, 0, &p1);
        fts5MultiIterEof(p, p1)==0;
        fts5MultiIterNext(p, p1, 0, 0)
................................................................................
    fts5MultiIterFree(p, p1);

    pData = fts5IdxMalloc(p, sizeof(Fts5Data) + doclist.n);
    if( pData ){
      pData->p = (u8*)&pData[1];
      pData->n = doclist.n;
      memcpy(pData->p, doclist.p, doclist.n);
      fts5MultiIterNew2(p, pData, bDesc, &pIter->pMulti);
    }
    fts5BufferFree(&doclist);
  }

  fts5StructureRelease(pStruct);
  sqlite3_free(aBuf);
}
................................................................................
int sqlite3Fts5IndexQuery(
  Fts5Index *p,                   /* FTS index to query */
  const char *pToken, int nToken, /* Token (or prefix) to query for */
  int flags,                      /* Mask of FTS5INDEX_QUERY_X flags */
  Fts5IndexIter **ppIter          /* OUT: New iterator object */
){
  Fts5Config *pConfig = p->pConfig;
  Fts5IndexIter *pRet;
  int iIdx = 0;
  Fts5Buffer buf = {0, 0, 0};

  /* If the QUERY_SCAN flag is set, all other flags must be clear. */
  assert( (flags & FTS5INDEX_QUERY_SCAN)==0
       || (flags & FTS5INDEX_QUERY_SCAN)==FTS5INDEX_QUERY_SCAN
  );

  if( sqlite3Fts5BufferGrow(&p->rc, &buf, nToken+1)==0 ){
    memcpy(&buf.p[1], pToken, nToken);
  }

#ifdef SQLITE_DEBUG
  if( flags & FTS5INDEX_QUERY_TEST_NOIDX ){
    assert( flags & FTS5INDEX_QUERY_PREFIX );
    iIdx = 1+pConfig->nPrefix;
  }else
#endif
  if( flags & FTS5INDEX_QUERY_PREFIX ){
    int nChar = fts5IndexCharlen(pToken, nToken);
    for(iIdx=1; iIdx<=pConfig->nPrefix; iIdx++){
      if( pConfig->aPrefix[iIdx-1]==nChar ) break;
    }
  }

  pRet = (Fts5IndexIter*)sqlite3Fts5MallocZero(&p->rc, sizeof(Fts5IndexIter));
  if( pRet ){
    pRet->pIndex = p;
    if( iIdx<=pConfig->nPrefix ){

      buf.p[0] = FTS5_MAIN_PREFIX + iIdx;
      pRet->pStruct = fts5StructureRead(p);
      if( pRet->pStruct ){
        fts5MultiIterNew(
            p, pRet->pStruct, 1, flags, buf.p, nToken+1, -1, 0, &pRet->pMulti
        );

      }
    }else{
      int bDesc = (flags & FTS5INDEX_QUERY_DESC)!=0;
      buf.p[0] = FTS5_MAIN_PREFIX;
      fts5SetupPrefixIter(p, bDesc, buf.p, nToken+1, pRet);
    }
  }

  if( p->rc ){
    sqlite3Fts5IterClose(pRet);
    pRet = 0;

  }
  *ppIter = pRet;
  sqlite3Fts5BufferFree(&buf);

  return fts5IndexReturn(p);
}

/*
** Return true if the iterator passed as the only argument is at EOF.
*/
int sqlite3Fts5IterEof(Fts5IndexIter *pIter){
  assert( pIter->pIndex->rc==SQLITE_OK );
  return fts5MultiIterEof(pIter->pIndex, pIter->pMulti);
}

/*
** Move to the next matching rowid. 
*/
int sqlite3Fts5IterNext(Fts5IndexIter *pIter){
  assert( pIter->pIndex->rc==SQLITE_OK );
  fts5MultiIterNext(pIter->pIndex, pIter->pMulti, 0, 0);
  return fts5IndexReturn(pIter->pIndex);
}

/*
** Move to the next matching term/rowid. Used by the fts5vocab module.
*/
int sqlite3Fts5IterNextScan(Fts5IndexIter *pIter){
  Fts5Index *p = pIter->pIndex;
  Fts5MultiSegIter *pMulti = pIter->pMulti;

  assert( pIter->pIndex->rc==SQLITE_OK );
  assert( pMulti );

  fts5MultiIterNext(p, pMulti, 0, 0);
  if( p->rc==SQLITE_OK ){
    Fts5SegIter *pSeg = &pMulti->aSeg[ pMulti->aFirst[1].iFirst ];
    if( pSeg->pLeaf && pSeg->term.p[0]!=FTS5_MAIN_PREFIX ){
      fts5DataRelease(pSeg->pLeaf);
      pSeg->pLeaf = 0;

    }
  }

  return fts5IndexReturn(pIter->pIndex);
}

/*
** Move to the next matching rowid that occurs at or after iMatch. The
** definition of "at or after" depends on whether this iterator iterates
** in ascending or descending rowid order.
*/
int sqlite3Fts5IterNextFrom(Fts5IndexIter *pIter, i64 iMatch){
  fts5MultiIterNextFrom(pIter->pIndex, pIter->pMulti, iMatch);
  return fts5IndexReturn(pIter->pIndex);
}

/*
** Return the current rowid.
*/
i64 sqlite3Fts5IterRowid(Fts5IndexIter *pIter){
  return fts5MultiIterRowid(pIter->pMulti);
}

/*
** Return the current term.
*/
const char *sqlite3Fts5IterTerm(Fts5IndexIter *pIter, int *pn){
  int n;
  const char *z = (const char*)fts5MultiIterTerm(pIter->pMulti, &n);
  *pn = n-1;
  return &z[1];
}


/*
** Return a pointer to a buffer containing a copy of the position list for
................................................................................
*/
int sqlite3Fts5IterPoslist(
  Fts5IndexIter *pIter, 
  const u8 **pp,                  /* OUT: Pointer to position-list data */
  int *pn,                        /* OUT: Size of position-list in bytes */
  i64 *piRowid                    /* OUT: Current rowid */
){
  Fts5MultiSegIter *pMulti = pIter->pMulti;
  Fts5SegIter *pSeg = &pMulti->aSeg[ pMulti->aFirst[1].iFirst ];
  assert( pIter->pIndex->rc==SQLITE_OK );
  *piRowid = pSeg->iRowid;
  *pn = pSeg->nPos;
  if( pSeg->iLeafOffset+pSeg->nPos <= pSeg->pLeaf->n ){
    *pp = &pSeg->pLeaf->p[pSeg->iLeafOffset];
  }else{
    fts5BufferZero(&pIter->poslist);
................................................................................
/*
** This function is similar to sqlite3Fts5IterPoslist(), except that it
** copies the position list into the buffer supplied as the second 
** argument.
*/
int sqlite3Fts5IterPoslistBuffer(Fts5IndexIter *pIter, Fts5Buffer *pBuf){
  Fts5Index *p = pIter->pIndex;
  Fts5MultiSegIter *pMulti = pIter->pMulti;

  assert( p->rc==SQLITE_OK );
  fts5BufferZero(pBuf);
  fts5MultiIterPoslist(p, pMulti, 0, pBuf);
  return fts5IndexReturn(p);
}

/*
** Close an iterator opened by an earlier call to sqlite3Fts5IndexQuery().
*/
void sqlite3Fts5IterClose(Fts5IndexIter *pIter){
  if( pIter ){

    fts5MultiIterFree(pIter->pIndex, pIter->pMulti);
    fts5StructureRelease(pIter->pStruct);
    fts5BufferFree(&pIter->poslist);
    fts5CloseReader(pIter->pIndex);
    sqlite3_free(pIter);
  }
}

/*
** Read the "averages" record into the buffer supplied as the second 
** argument. Return SQLITE_OK if successful, or an SQLite error code
** if an error occurs.
................................................................................
  }else
  if( rc==SQLITE_OK && (pPrev->n!=n || memcmp(pPrev->p, z, n)) ){
    u64 cksum3 = *pCksum;
    const char *zTerm = (const char*)&pPrev->p[1];  /* term sans prefix-byte */
    int nTerm = pPrev->n-1;            /* Size of zTerm in bytes */
    int iIdx = (pPrev->p[0] - FTS5_MAIN_PREFIX);
    int flags = (iIdx==0 ? 0 : FTS5INDEX_QUERY_PREFIX);
    int rc;
    u64 ck1 = 0;
    u64 ck2 = 0;

    /* Check that the results returned for ASC and DESC queries are
    ** the same. If not, call this corruption.  */
    rc = fts5QueryCksum(p, iIdx, zTerm, nTerm, flags, &ck1);
    if( rc==SQLITE_OK ){
................................................................................
** checksum does not match. Return SQLITE_OK if all checks pass without
** error, or some other SQLite error code if another error (e.g. OOM)
** occurs.
*/
int sqlite3Fts5IndexIntegrityCheck(Fts5Index *p, u64 cksum){
  u64 cksum2 = 0;                 /* Checksum based on contents of indexes */
  Fts5Buffer poslist = {0,0,0};   /* Buffer used to hold a poslist */
  Fts5MultiSegIter *pIter;        /* Used to iterate through entire index */
  Fts5Structure *pStruct;         /* Index structure */

  /* Used by extra internal tests only run if NDEBUG is not defined */
  u64 cksum3 = 0;                 /* Checksum based on contents of indexes */
  Fts5Buffer term = {0,0,0};      /* Buffer used to hold most recent term */
  
  /* Load the FTS index structure */
................................................................................
  ){
    int n;                      /* Size of term in bytes */
    i64 iPos = 0;               /* Position read from poslist */
    int iOff = 0;               /* Offset within poslist */
    i64 iRowid = fts5MultiIterRowid(pIter);
    char *z = (char*)fts5MultiIterTerm(pIter, &n);




    poslist.n = 0;
    fts5MultiIterPoslist(p, pIter, 0, &poslist);
    while( 0==sqlite3Fts5PoslistNext64(poslist.p, poslist.n, &iOff, &iPos) ){
      int iCol = FTS5_POS2COLUMN(iPos);
      int iTokOff = FTS5_POS2OFFSET(iPos);
      cksum2 ^= fts5IndexEntryCksum(iRowid, iCol, iTokOff, -1, z, n);
    }

    /* If this is a new term, query for it. Update cksum3 with the results. */
    fts5TestTerm(p, &term, z, n, cksum2, &cksum3);
  }
  fts5TestTerm(p, &term, 0, 0, cksum2, &cksum3);

  fts5MultiIterFree(p, pIter);
  if( p->rc==SQLITE_OK && cksum!=cksum2 ) p->rc = FTS5_CORRUPT;

  fts5StructureRelease(pStruct);
................................................................................
  Fts5Structure *p
){
  int iLvl, iSeg;                 /* Iterate through levels, segments */

  for(iLvl=0; iLvl<p->nLevel; iLvl++){
    Fts5StructureLevel *pLvl = &p->aLevel[iLvl];
    sqlite3Fts5BufferAppendPrintf(pRc, pBuf, 
        " {lvl=%d nMerge=%d", iLvl, pLvl->nMerge
    );
    for(iSeg=0; iSeg<pLvl->nSeg; iSeg++){
      Fts5StructureSegment *pSeg = &pLvl->aSeg[iSeg];
      sqlite3Fts5BufferAppendPrintf(pRc, pBuf, 
          " {id=%d h=%d leaves=%d..%d}", pSeg->iSegid, pSeg->nHeight, 
          pSeg->pgnoFirst, pSeg->pgnoLast
      );

typedef struct Fts5BtreeIter Fts5BtreeIter;
typedef struct Fts5BtreeIterLevel Fts5BtreeIterLevel;
typedef struct Fts5Data Fts5Data;
typedef struct Fts5DlidxIter Fts5DlidxIter;
typedef struct Fts5DlidxLvl Fts5DlidxLvl;
typedef struct Fts5DlidxWriter Fts5DlidxWriter;

typedef struct Fts5NodeIter Fts5NodeIter;
typedef struct Fts5PageWriter Fts5PageWriter;
typedef struct Fts5SegIter Fts5SegIter;
typedef struct Fts5DoclistIter Fts5DoclistIter;
typedef struct Fts5SegWriter Fts5SegWriter;
typedef struct Fts5Structure Fts5Structure;
typedef struct Fts5StructureLevel Fts5StructureLevel;
................................................................................

  /* Output variables. aPoslist==0 at EOF */
  i64 iRowid;
  u8 *aPoslist;
  int nPoslist;
};











/*
** The contents of the "structure" record for each index are represented
** using an Fts5Structure record in memory. Which uses instances of the 
** other Fts5StructureXXX types as components.
*/
struct Fts5StructureSegment {
  int iSegid;                     /* Segment id */
................................................................................
};
struct Fts5StructureLevel {
  int nMerge;                     /* Number of segments in incr-merge */
  int nSeg;                       /* Total number of segments on level */
  Fts5StructureSegment *aSeg;     /* Array of segments. aSeg[0] is oldest. */
};
struct Fts5Structure {
  int nRef;                       /* Object reference count */
  u64 nWriteCounter;              /* Total leaves written to level 0 */
  int nSegment;                   /* Total segments in this structure */
  int nLevel;                     /* Number of levels in this index */
  Fts5StructureLevel aLevel[0];   /* Array of nLevel level objects */
};

/*
................................................................................

typedef struct Fts5CResult Fts5CResult;
struct Fts5CResult {
  u16 iFirst;                     /* aSeg[] index of firstest iterator */
  u8 bTermEq;                     /* True if the terms are equal */
};









/*
** Object for iterating through a single segment, visiting each term/docid
** pair in the segment.
**
** pSeg:
**   The segment to iterate through.
**
................................................................................
  int nPos;                       /* Number of bytes in current position list */
  int bDel;                       /* True if the delete flag is set */
};

#define FTS5_SEGITER_ONETERM 0x01
#define FTS5_SEGITER_REVERSE 0x02


/*
** poslist:
**   Used by sqlite3Fts5IterPoslist() when the poslist needs to be buffered.
**   There is no way to tell if this is populated or not.
*/
struct Fts5IndexIter {
  Fts5Index *pIndex;              /* Index that owns this iterator */
  Fts5Structure *pStruct;         /* Database structure for this iterator */
  Fts5Buffer poslist;             /* Buffer containing current poslist */

  int nSeg;                       /* Size of aSeg[] array */
  int bRev;                       /* True to iterate in reverse order */
  int bSkipEmpty;                 /* True to skip deleted entries */
  int bEof;                       /* True at EOF */

  i64 iSwitchRowid;               /* Firstest rowid of other than aFirst[1] */
  Fts5CResult *aFirst;            /* Current merge state (see above) */
  Fts5SegIter aSeg[1];            /* Array of segment iterators */
};


/*
** Object for iterating through the conents of a single internal node in 
** memory.
*/
struct Fts5NodeIter {
  /* Internal. Set and managed by fts5NodeIterXXX() functions. Except, 
................................................................................
  Fts5Buffer term;                /* Current term */
  int iLeaf;                      /* Leaf containing terms >= current term */
  int nEmpty;                     /* Number of "empty" leaves following iLeaf */
  int bEof;                       /* Set to true at EOF */
  int bDlidx;                     /* True if there exists a dlidx */
};


/*
** The first argument passed to this macro is a pointer to an Fts5Buffer
** object.
*/
#define fts5BufferSize(pBuf,n) {                \
  if( pBuf->nSpace<n ) {                        \
    u8 *pNew = sqlite3_realloc(pBuf->p, n);     \
    if( pNew==0 ){                              \
      sqlite3_free(pBuf->p);                    \
    }                                           \
    pBuf->nSpace = n;                           \
    pBuf->p = pNew;                             \
  }                                             \
}

static void fts5PutU16(u8 *aOut, u16 iVal){
  aOut[0] = (iVal>>8);
  aOut[1] = (iVal&0xFF);
}

static u16 fts5GetU16(const u8 *aIn){
................................................................................
    ** backing store corruption.  */
    if( rc==SQLITE_ERROR ) rc = FTS5_CORRUPT;

    if( rc==SQLITE_OK ){
      u8 *aOut;                   /* Read blob data into this buffer */
      int nByte = sqlite3_blob_bytes(p->pReader);
      if( pBuf ){
        fts5BufferSize(pBuf, MAX(nByte, p->pConfig->pgsz) + 20);
        pBuf->n = nByte;
        aOut = pBuf->p;
        if( aOut==0 ){
          rc = SQLITE_NOMEM;
        }
      }else{
        int nSpace = nByte + FTS5_DATA_ZERO_PADDING;
        pRet = (Fts5Data*)sqlite3_malloc(nSpace+sizeof(Fts5Data));
        if( pRet ){
          pRet->n = nByte;
          aOut = pRet->p = (u8*)&pRet[1];
        }else{
          rc = SQLITE_NOMEM;
        }
      }

      if( rc==SQLITE_OK ){
        rc = sqlite3_blob_read(p->pReader, aOut, nByte, 0);
      }
      if( rc!=SQLITE_OK ){
................................................................................
}

/*
** Release a reference to an Fts5Structure object returned by an earlier 
** call to fts5StructureRead() or fts5StructureDecode().
*/
static void fts5StructureRelease(Fts5Structure *pStruct){
  if( pStruct && 0>=(--pStruct->nRef) ){
    int i;
    assert( pStruct->nRef==0 );
    for(i=0; i<pStruct->nLevel; i++){
      sqlite3_free(pStruct->aLevel[i].aSeg);
    }
    sqlite3_free(pStruct);
  }
}

static void fts5StructureRef(Fts5Structure *pStruct){
  pStruct->nRef++;
}

/*
** Deserialize and return the structure record currently stored in serialized
** form within buffer pData/nData.
**
** The Fts5Structure.aLevel[] and each Fts5StructureLevel.aSeg[] array
** are over-allocated by one slot. This allows the structure contents
................................................................................
  nByte = (
      sizeof(Fts5Structure) +                    /* Main structure */
      sizeof(Fts5StructureLevel) * (nLevel)      /* aLevel[] array */
  );
  pRet = (Fts5Structure*)sqlite3Fts5MallocZero(&rc, nByte);

  if( pRet ){
    pRet->nRef = 1;
    pRet->nLevel = nLevel;
    pRet->nSegment = nSegment;
    i += sqlite3Fts5GetVarint(&pData[i], &pRet->nWriteCounter);

    for(iLvl=0; rc==SQLITE_OK && iLvl<nLevel; iLvl++){
      Fts5StructureLevel *pLvl = &pRet->aLevel[iLvl];
      int nTotal;
................................................................................
** If an error occurs, NULL is returned and an error code left in the
** Fts5Index handle. If an error has already occurred when this function
** is called, it is a no-op.
*/
static Fts5Structure *fts5StructureRead(Fts5Index *p){
  Fts5Config *pConfig = p->pConfig;
  Fts5Structure *pRet = 0;        /* Object to return */

  int iCookie;                    /* Configuration cookie */
  Fts5Buffer buf = {0, 0, 0};

  fts5DataBuffer(p, &buf, FTS5_STRUCTURE_ROWID);
  if( buf.p==0 ) return 0;
  assert( buf.nSpace>=(buf.n + FTS5_DATA_ZERO_PADDING) );
  memset(&buf.p[buf.n], 0, FTS5_DATA_ZERO_PADDING);
  p->rc = fts5StructureDecode(buf.p, buf.n, &iCookie, &pRet);

  if( p->rc==SQLITE_OK && pConfig->iCookie!=iCookie ){
    p->rc = sqlite3Fts5ConfigLoad(pConfig, iCookie);
  }

  fts5BufferFree(&buf);
  if( p->rc!=SQLITE_OK ){
    fts5StructureRelease(pRet);
    pRet = 0;
  }
  return pRet;
}

................................................................................
      p->rc = FTS5_CORRUPT;
    }else{
      const u8 *a = &pIter->pLeaf->p[iOff];
      pIter->iLeafOffset += fts5GetPoslistSize(a, &pIter->nPos, &pIter->bDel);
    }
  }
}

static void fts5SegIterLoadRowid(Fts5Index *p, Fts5SegIter *pIter){
  u8 *a = pIter->pLeaf->p;        /* Buffer to read data from */
  int iOff = pIter->iLeafOffset;

  if( iOff>=pIter->pLeaf->n ){
    fts5SegIterNextPage(p, pIter);
    if( pIter->pLeaf==0 ){
      if( p->rc==SQLITE_OK ) p->rc = FTS5_CORRUPT;
      return;
    }
    iOff = 4;
    a = pIter->pLeaf->p;
  }
  iOff += sqlite3Fts5GetVarint(&a[iOff], (u64*)&pIter->iRowid);
  pIter->iLeafOffset = iOff;
}

/*
** Fts5SegIter.iLeafOffset currently points to the first byte of the 
** "nSuffix" field of a term. Function parameter nKeep contains the value
** of the "nPrefix" field (if there was one - it is passed 0 if this is
** the first term in the segment).
**
................................................................................

  iOff += fts5GetVarint32(&a[iOff], nNew);
  pIter->term.n = nKeep;
  fts5BufferAppendBlob(&p->rc, &pIter->term, nNew, &a[iOff]);
  iOff += nNew;
  pIter->iTermLeafOffset = iOff;
  pIter->iTermLeafPgno = pIter->iLeafPgno;
  pIter->iLeafOffset = iOff;










  fts5SegIterLoadRowid(p, pIter);
}

/*
** Initialize the iterator object pIter to iterate through the entries in
** segment pSeg. The iterator is left pointing to the first entry when 
** this function returns.
**
................................................................................
}

/*
** Return true if the iterator passed as the second argument currently
** points to a delete marker. A delete marker is an entry with a 0 byte
** position-list.
*/
static int fts5MultiIterIsEmpty(Fts5Index *p, Fts5IndexIter *pIter){
  Fts5SegIter *pSeg = &pIter->aSeg[pIter->aFirst[1].iFirst];
  return (p->rc==SQLITE_OK && pSeg->pLeaf && pSeg->nPos==0);
}

/*
** Advance iterator pIter to the next entry. 
**
................................................................................
      iOff += fts5GetPoslistSize(&pLeaf->p[iOff], &nPos, &bDummy);
      iOff += nPos;
    }
  }

  pIter->pDlidx = fts5DlidxIterInit(p, bRev, iSeg, pIter->iTermLeafPgno);
}

#ifdef SQLITE_DEBUG
static void fts5AssertNodeSeekOk(
  Fts5Buffer *pNode,
  const u8 *pTerm, int nTerm,     /* Term to search for */
  int iExpectPg,
  int bExpectDlidx
){
  int bDlidx;
  int iPg;
  int rc = SQLITE_OK;
  Fts5NodeIter node;

  fts5NodeIterInit(pNode->p, pNode->n, &node);
  assert( node.term.n==0 );
  iPg = node.iChild;
  bDlidx = node.bDlidx;
  for(fts5NodeIterNext(&rc, &node);
      node.aData && fts5BufferCompareBlob(&node.term, pTerm, nTerm)<=0;
      fts5NodeIterNext(&rc, &node)
  ){
    iPg = node.iChild;
    bDlidx = node.bDlidx;
  }
  fts5NodeIterFree(&node);

  assert( rc!=SQLITE_OK || iPg==iExpectPg );
  assert( rc!=SQLITE_OK || bDlidx==bExpectDlidx );
}
#else
#define fts5AssertNodeSeekOk(v,w,x,y,z)
#endif

/*
** Argument pNode is an internal b-tree node. This function searches
** within the node for the largest term that is smaller than or equal
** to (pTerm/nTerm).
**
** It returns the associated page number. Or, if (pTerm/nTerm) is smaller
** than all terms within the node, the leftmost child page number. 
**
** Before returning, (*pbDlidx) is set to true if the last term on the
** returned child page number has a doclist-index. Or left as is otherwise.
*/
static int fts5NodeSeek(
  Fts5Buffer *pNode,              /* Node to search */
  const u8 *pTerm, int nTerm,     /* Term to search for */
  int *pbDlidx                    /* OUT: True if dlidx flag is set */
){
  int iPg;
  u8 *pPtr = pNode->p;
  u8 *pEnd = &pPtr[pNode->n];
  int nMatch = 0;                 /* Number of bytes of pTerm already matched */
  
  assert( *pbDlidx==0 );

  pPtr += fts5GetVarint32(pPtr, iPg);
  while( pPtr<pEnd ){
    int nEmpty = 0;
    int nKeep;
    int nNew;

    /* If there is a "no terms" record at pPtr, read it now. Store the
    ** number of termless pages in nEmpty. If it indicates a doclist-index, 
    ** set (*pbDlidx) to true.*/
    if( *pPtr<2 ){
      *pbDlidx = (*pPtr==0x01);
      pPtr++;
      pPtr += fts5GetVarint32(pPtr, nEmpty);
      if( pPtr>=pEnd ) break;
    }

    /* Read the next "term" pointer. Set nKeep to the number of bytes to
    ** keep from the previous term, and nNew to the number of bytes of
    ** new data that will be appended to it. */
    nKeep = (int)*pPtr++;
    nNew = (int)*pPtr++;
    if( (nKeep | nNew) & 0x0080 ){
      pPtr -= 2;
      pPtr += fts5GetVarint32(pPtr, nKeep);
      pPtr += fts5GetVarint32(pPtr, nNew);
    }
    nKeep -= 2;

    /* Compare (pTerm/nTerm) to the current term on the node (the one described
    ** by nKeep/nNew). If the node term is larger, break out of the while()
    ** loop. 
    **
    ** Otherwise, if (pTerm/nTerm) is larger or the two terms are equal, 
    ** leave variable nMatch set to the size of the largest prefix common to
    ** both terms in bytes.  */
    if( nKeep==nMatch ){
      int nTst = MIN(nNew, nTerm-nMatch);
      int i;
      for(i=0; i<nTst; i++){
        if( pTerm[nKeep+i]!=pPtr[i] ) break;
      }
      nMatch += i;
      assert( nMatch<=nTerm );

      if( i<nNew && (nMatch==nTerm || pPtr[i] > pTerm[nMatch]) ) break;
    }else if( nKeep<nMatch ){
      break;
    }

    iPg += 1 + nEmpty;
    *pbDlidx = 0;
    pPtr += nNew;
  }

  fts5AssertNodeSeekOk(pNode, pTerm, nTerm, iPg, *pbDlidx);
  return iPg;
}

#define fts5IndexGetVarint32(a, iOff, nVal) {     \
  nVal = a[iOff++];                               \
  if( nVal & 0x80 ){                              \
    iOff--;                                       \
    iOff += fts5GetVarint32(&a[iOff], nVal);      \
  }                                               \
}

#define fts5IndexSkipVarint(a, iOff) {            \
  int iEnd = iOff+9;                              \
  while( (a[iOff++] & 0x80) && iOff<iEnd );       \
}

/*
** The iterator object passed as the second argument currently contains
** no valid values except for the Fts5SegIter.pLeaf member variable. This
** function searches the leaf page for a term matching (pTerm/nTerm).
**
** If the specified term is found on the page, then the iterator is left
** pointing to it. If argument bGe is zero and the term is not found,
** the iterator is left pointing at EOF.
**
** If bGe is non-zero and the specified term is not found, then the
** iterator is left pointing to the smallest term in the segment that
** is larger than the specified term, even if this term is not on the
** current page.
*/
static void fts5LeafSeek(
  Fts5Index *p,                   /* Leave any error code here */
  int bGe,                        /* True for a >= search */
  Fts5SegIter *pIter,             /* Iterator to seek */
  const u8 *pTerm, int nTerm      /* Term to search for */
){
  int iOff;
  const u8 *a = pIter->pLeaf->p;
  int n = pIter->pLeaf->n;

  int nMatch = 0;
  int nKeep = 0;
  int nNew = 0;

  assert( p->rc==SQLITE_OK );
  assert( pIter->pLeaf );

  iOff = fts5GetU16(&a[2]);
  if( iOff<4 || iOff>=n ){
    p->rc = FTS5_CORRUPT;
    return;
  }

  while( 1 ){
    int i;
    int nCmp;
    i64 rowid;

    /* Figure out how many new bytes are in this term */
    fts5IndexGetVarint32(a, iOff, nNew);

    if( nKeep<nMatch ){
      goto search_failed;
    }

    assert( nKeep>=nMatch );
    if( nKeep==nMatch ){
      nCmp = MIN(nNew, nTerm-nMatch);
      for(i=0; i<nCmp; i++){
        if( a[iOff+i]!=pTerm[nMatch+i] ) break;
      }
      nMatch += i;

      if( nTerm==nMatch ){
        if( i==nNew ){
          goto search_success;
        }else{
          goto search_failed;
        }
      }else if( i<nNew && a[iOff+i]>pTerm[nMatch] ){
        goto search_failed;
      }
    }
    iOff += nNew;

    /* Skip past the doclist. If the end of the page is reached, bail out. */
    while( 1 ){
      int nPos;

      /* Skip past docid delta */
      fts5IndexSkipVarint(a, iOff);

      /* Skip past position list */
      fts5IndexGetVarint32(a, iOff, nPos);
      iOff += (nPos >> 1);
      if( iOff>=(n-1) ){
        iOff = n;
        goto search_failed;
      }

      /* If this is the end of the doclist, break out of the loop */
      if( a[iOff]==0x00 ){
        iOff++;
        break;
      }
    };

    /* Read the nKeep field of the next term. */
    fts5IndexGetVarint32(a, iOff, nKeep);
  }

 search_failed:
  if( bGe==0 ){
    fts5DataRelease(pIter->pLeaf);
    pIter->pLeaf = 0;
    return;
  }else if( iOff>=n ){
    do {
      fts5SegIterNextPage(p, pIter);
      if( pIter->pLeaf==0 ) return;
      a = pIter->pLeaf->p;
      iOff = fts5GetU16(&a[2]);
      if( iOff ){
        if( iOff<4 || iOff>=n ){
          p->rc = FTS5_CORRUPT;
        }else{
          nKeep = 0;
          iOff += fts5GetVarint32(&a[iOff], nNew);
          break;
        }
      }
    }while( 1 );
  }

 search_success:
  pIter->iLeafOffset = iOff + nNew;
  pIter->iTermLeafOffset = pIter->iLeafOffset;
  pIter->iTermLeafPgno = pIter->iLeafPgno;

  fts5BufferSet(&p->rc, &pIter->term, nKeep, pTerm);
  fts5BufferAppendBlob(&p->rc, &pIter->term, nNew, &a[iOff]);

  fts5SegIterLoadRowid(p, pIter);
  fts5SegIterLoadNPos(p, pIter);
}

/*
** Initialize the object pIter to point to term pTerm/nTerm within segment
** pSeg. If there is no such term in the index, the iterator is set to EOF.
**
** If an error occurs, Fts5Index.rc is set to an appropriate error code. If 
** an error has already occurred when this function is called, it is a no-op.
*/
static void fts5SegIterSeekInit(
  Fts5Index *p,                   /* FTS5 backend */
  Fts5Buffer *pBuf,               /* Buffer to use for loading pages */
  const u8 *pTerm, int nTerm,     /* Term to seek to */
  int flags,                      /* Mask of FTS5INDEX_XXX flags */
  Fts5StructureSegment *pSeg,     /* Description of segment */
  Fts5SegIter *pIter              /* Object to populate */
){
  int iPg = 1;
  int h;
  int bGe = (flags & FTS5INDEX_QUERY_SCAN);
  int bDlidx = 0;                 /* True if there is a doclist-index */
  Fts5Data *pLeaf;

  static int nCall = 0;
  nCall++;

  assert( bGe==0 || (flags & FTS5INDEX_QUERY_DESC)==0 );
  assert( pTerm && nTerm );
  memset(pIter, 0, sizeof(*pIter));
  pIter->pSeg = pSeg;

  /* This block sets stack variable iPg to the leaf page number that may
  ** contain term (pTerm/nTerm), if it is present in the segment. */
  for(h=pSeg->nHeight-1; h>0; h--){

    i64 iRowid = FTS5_SEGMENT_ROWID(pSeg->iSegid, h, iPg);

    fts5DataBuffer(p, pBuf, iRowid);
    if( p->rc ) break;















    iPg = fts5NodeSeek(pBuf, pTerm, nTerm, &bDlidx);
  }

  if( iPg<pSeg->pgnoFirst ){
    iPg = pSeg->pgnoFirst;
    bDlidx = 0;
  }

  pIter->iLeafPgno = iPg - 1;
  fts5SegIterNextPage(p, pIter);


















  if( pIter->pLeaf ){


    fts5LeafSeek(p, bGe, pIter, pTerm, nTerm);
  }

  if( p->rc==SQLITE_OK && bGe==0 ){
    pIter->flags |= FTS5_SEGITER_ONETERM;
    if( pIter->pLeaf ){
      if( flags & FTS5INDEX_QUERY_DESC ){
        pIter->flags |= FTS5_SEGITER_REVERSE;
................................................................................
        fts5SegIterLoadDlidx(p, pIter);
      }
      if( flags & FTS5INDEX_QUERY_DESC ){
        fts5SegIterReverse(p, pIter);
      }
    }
  }

  /* Either:
  **
  **   1) an error has occurred, or
  **   2) the iterator points to EOF, or
  **   3) the iterator points to an entry with term (pTerm/nTerm), or
  **   4) the FTS5INDEX_QUERY_SCAN flag was set and the iterator points
  **      to an entry with a term greater than or equal to (pTerm/nTerm).
  */
  assert( p->rc!=SQLITE_OK                                          /* 1 */
   || pIter->pLeaf==0                                               /* 2 */
   || fts5BufferCompareBlob(&pIter->term, pTerm, nTerm)==0          /* 3 */
   || (bGe && fts5BufferCompareBlob(&pIter->term, pTerm, nTerm)>0)  /* 4 */
  );
}

/*
** Initialize the object pIter to point to term pTerm/nTerm within the
** in-memory hash table. If there is no such term in the hash-table, the 
** iterator is set to EOF.
**
................................................................................
/*
** This function is used as part of the big assert() procedure implemented by
** fts5AssertMultiIterSetup(). It ensures that the result currently stored
** in *pRes is the correct result of comparing the current positions of the
** two iterators.
*/
static void fts5AssertComparisonResult(
  Fts5IndexIter *pIter, 
  Fts5SegIter *p1,
  Fts5SegIter *p2,
  Fts5CResult *pRes
){
  int i1 = p1 - pIter->aSeg;
  int i2 = p2 - pIter->aSeg;

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

/*
** This function is a no-op unless SQLITE_DEBUG is defined when this module
** is compiled. In that case, this function is essentially an assert() 
** statement used to verify that the contents of the pIter->aFirst[] array
** are correct.
*/
static void fts5AssertMultiIterSetup(Fts5Index *p, Fts5IndexIter *pIter){
  if( p->rc==SQLITE_OK ){
    Fts5SegIter *pFirst = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
    int i;

    assert( (pFirst->pLeaf==0)==pIter->bEof );

    /* Check that pIter->iSwitchRowid is set correctly. */
    for(i=0; i<pIter->nSeg; i++){
      Fts5SegIter *p1 = &pIter->aSeg[i];
      assert( p1==pFirst 
           || p1->pLeaf==0 
           || fts5BufferCompare(&pFirst->term, &p1->term) 
           || p1->iRowid==pIter->iSwitchRowid
           || (p1->iRowid<pIter->iSwitchRowid)==pIter->bRev
      );
    }

    for(i=0; i<pIter->nSeg; i+=2){
      Fts5SegIter *p1 = &pIter->aSeg[i];
      Fts5SegIter *p2 = &pIter->aSeg[i+1];
      Fts5CResult *pRes = &pIter->aFirst[(pIter->nSeg + i) / 2];
      fts5AssertComparisonResult(pIter, p1, p2, pRes);
    }

    for(i=1; i<(pIter->nSeg / 2); i+=2){

      Fts5SegIter *p1 = &pIter->aSeg[ pIter->aFirst[i*2].iFirst ];
      Fts5SegIter *p2 = &pIter->aSeg[ pIter->aFirst[i*2+1].iFirst ];

      Fts5CResult *pRes = &pIter->aFirst[i];
      fts5AssertComparisonResult(pIter, p1, p2, pRes);
    }
  }
}
#else
# define fts5AssertMultiIterSetup(x,y)
#endif
................................................................................
** Do the comparison necessary to populate pIter->aFirst[iOut].
**
** If the returned value is non-zero, then it is the index of an entry
** in the pIter->aSeg[] array that is (a) not at EOF, and (b) pointing
** to a key that is a duplicate of another, higher priority, 
** segment-iterator in the pSeg->aSeg[] array.
*/
static int fts5MultiIterDoCompare(Fts5IndexIter *pIter, int iOut){
  int i1;                         /* Index of left-hand Fts5SegIter */
  int i2;                         /* Index of right-hand Fts5SegIter */
  int iRes;
  Fts5SegIter *p1;                /* Left-hand Fts5SegIter */
  Fts5SegIter *p2;                /* Right-hand Fts5SegIter */
  Fts5CResult *pRes = &pIter->aFirst[iOut];

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


/*
** Free the iterator object passed as the second argument.
*/
static void fts5MultiIterFree(Fts5Index *p, Fts5IndexIter *pIter){
  if( pIter ){
    int i;
    for(i=0; i<pIter->nSeg; i++){
      fts5SegIterClear(&pIter->aSeg[i]);
    }
    fts5StructureRelease(pIter->pStruct);
    fts5BufferFree(&pIter->poslist);
    sqlite3_free(pIter);
  }
}

static void fts5MultiIterAdvanced(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5IndexIter *pIter,           /* Iterator to update aFirst[] array for */
  int iChanged,                   /* Index of sub-iterator just advanced */
  int iMinset                     /* Minimum entry in aFirst[] to set */
){
  int i;
  for(i=(pIter->nSeg+iChanged)/2; i>=iMinset && p->rc==SQLITE_OK; i=i/2){
    int iEq;
    if( (iEq = fts5MultiIterDoCompare(pIter, i)) ){
      fts5SegIterNext(p, &pIter->aSeg[iEq], 0);
      i = pIter->nSeg + iEq;
    }
  }
}

/*
** Sub-iterator iChanged of iterator pIter has just been advanced. It still
** points to the same term though - just a different rowid. This function
** attempts to update the contents of the pIter->aFirst[] accordingly.
** If it does so successfully, 0 is returned. Otherwise 1.
**
** If non-zero is returned, the caller should call fts5MultiIterAdvanced()
** on the iterator instead. That function does the same as this one, except
** that it deals with more complicated cases as well.
*/ 
static int fts5MultiIterAdvanceRowid(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5IndexIter *pIter,           /* Iterator to update aFirst[] array for */
  int iChanged                    /* Index of sub-iterator just advanced */
){

  Fts5SegIter *pNew = &pIter->aSeg[iChanged];


  if( pNew->iRowid==pIter->iSwitchRowid
   || (pNew->iRowid<pIter->iSwitchRowid)==pIter->bRev
  ){
    int i;
    Fts5SegIter *pOther = &pIter->aSeg[iChanged ^ 0x0001];
    pIter->iSwitchRowid = pIter->bRev ? SMALLEST_INT64 : LARGEST_INT64;
    for(i=(pIter->nSeg+iChanged)/2; 1; i=i/2){
      Fts5CResult *pRes = &pIter->aFirst[i];

      assert( pNew->pLeaf );
      assert( pRes->bTermEq==0 || pOther->pLeaf );

      if( pRes->bTermEq ){
        if( pNew->iRowid==pOther->iRowid ){
          return 1;
        }else if( (pOther->iRowid>pNew->iRowid)==pIter->bRev ){
          pIter->iSwitchRowid = pOther->iRowid;
          pNew = pOther;
        }else if( (pOther->iRowid>pIter->iSwitchRowid)==pIter->bRev ){
          pIter->iSwitchRowid = pOther->iRowid;
        }
      }
      pRes->iFirst = (pNew - pIter->aSeg);
      if( i==1 ) break;

      pOther = &pIter->aSeg[ pIter->aFirst[i ^ 0x0001].iFirst ];
    }
  }

  return 0;
}

/*
** Set the pIter->bEof variable based on the state of the sub-iterators.
*/
static void fts5MultiIterSetEof(Fts5IndexIter *pIter){
  Fts5SegIter *pSeg = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
  pIter->bEof = pSeg->pLeaf==0;
  pIter->iSwitchRowid = pSeg->iRowid;
}

/*
** Move the iterator to the next entry. 
**
** If an error occurs, an error code is left in Fts5Index.rc. It is not 
** considered an error if the iterator reaches EOF, or if it is already at 
** EOF when this function is called.
*/
static void fts5MultiIterNext(
  Fts5Index *p, 
  Fts5IndexIter *pIter,
  int bFrom,                      /* True if argument iFrom is valid */
  i64 iFrom                       /* Advance at least as far as this */
){
  if( p->rc==SQLITE_OK ){
    int bUseFrom = bFrom;
    do {
      int iFirst = pIter->aFirst[1].iFirst;
................................................................................
        fts5SegIterNext(p, pSeg, &bNewTerm);
      }

      if( pSeg->pLeaf==0 || bNewTerm 
       || fts5MultiIterAdvanceRowid(p, pIter, iFirst)
      ){
        fts5MultiIterAdvanced(p, pIter, iFirst, 1);
        fts5MultiIterSetEof(pIter);
      }
      fts5AssertMultiIterSetup(p, pIter);

      bUseFrom = 0;
    }while( pIter->bSkipEmpty && fts5MultiIterIsEmpty(p, pIter) );
  }
}

static Fts5IndexIter *fts5MultiIterAlloc(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  int nSeg
){
  Fts5IndexIter *pNew;
  int nSlot;                      /* Power of two >= nSeg */

  for(nSlot=2; nSlot<nSeg; nSlot=nSlot*2);
  pNew = fts5IdxMalloc(p, 
      sizeof(Fts5IndexIter) +             /* pNew */
      sizeof(Fts5SegIter) * (nSlot-1) +   /* pNew->aSeg[] */
      sizeof(Fts5CResult) * nSlot         /* pNew->aFirst[] */
  );
  if( pNew ){
    pNew->nSeg = nSlot;

    pNew->aFirst = (Fts5CResult*)&pNew->aSeg[nSlot];
    pNew->pIndex = p;
  }
  return pNew;
}

/*
** Allocate a new Fts5IndexIter object.
**
** The new object will be used to iterate through data in structure pStruct.
** If iLevel is -ve, then all data in all segments is merged. Or, if iLevel
** is zero or greater, data from the first nSegment segments on level iLevel
** is merged.
**
** The iterator initially points to the first term/rowid entry in the 
................................................................................
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5Structure *pStruct,         /* Structure of specific index */
  int bSkipEmpty,                 /* True to ignore delete-keys */
  int flags,                      /* FTS5INDEX_QUERY_XXX flags */
  const u8 *pTerm, int nTerm,     /* Term to seek to (or NULL/0) */
  int iLevel,                     /* Level to iterate (-1 for all) */
  int nSegment,                   /* Number of segments to merge (iLevel>=0) */
  Fts5IndexIter **ppOut           /* New object */
){
  int nSeg = 0;                   /* Number of segment-iters in use */
  int iIter = 0;                  /* */
  int iSeg;                       /* Used to iterate through segments */
  Fts5Buffer buf = {0,0,0};       /* Buffer used by fts5SegIterSeekInit() */
  Fts5StructureLevel *pLvl;
  Fts5IndexIter *pNew;

  assert( (pTerm==0 && nTerm==0) || iLevel<0 );

  /* Allocate space for the new multi-seg-iterator. */
  if( p->rc==SQLITE_OK ){
    if( iLevel<0 ){
      assert( pStruct->nSegment==fts5StructureCountSegments(pStruct) );
................................................................................
      nSeg = MIN(pStruct->aLevel[iLevel].nSeg, nSegment);
    }
  }
  *ppOut = pNew = fts5MultiIterAlloc(p, nSeg);
  if( pNew==0 ) return;
  pNew->bRev = (0!=(flags & FTS5INDEX_QUERY_DESC));
  pNew->bSkipEmpty = bSkipEmpty;
  pNew->pStruct = pStruct;
  fts5StructureRef(pStruct);

  /* Initialize each of the component segment iterators. */
  if( iLevel<0 ){
    Fts5StructureLevel *pEnd = &pStruct->aLevel[pStruct->nLevel];
    if( p->pHash ){
      /* Add a segment iterator for the current contents of the hash table. */
      Fts5SegIter *pIter = &pNew->aSeg[iIter++];
................................................................................
    for(pLvl=&pStruct->aLevel[0]; pLvl<pEnd; pLvl++){
      for(iSeg=pLvl->nSeg-1; iSeg>=0; iSeg--){
        Fts5StructureSegment *pSeg = &pLvl->aSeg[iSeg];
        Fts5SegIter *pIter = &pNew->aSeg[iIter++];
        if( pTerm==0 ){
          fts5SegIterInit(p, pSeg, pIter);
        }else{
          fts5SegIterSeekInit(p, &buf, pTerm, nTerm, flags, pSeg, pIter);
        }
      }
    }
  }else{
    pLvl = &pStruct->aLevel[iLevel];
    for(iSeg=nSeg-1; iSeg>=0; iSeg--){
      fts5SegIterInit(p, &pLvl->aSeg[iSeg], &pNew->aSeg[iIter++]);
................................................................................
    for(iIter=pNew->nSeg-1; iIter>0; iIter--){
      int iEq;
      if( (iEq = fts5MultiIterDoCompare(pNew, iIter)) ){
        fts5SegIterNext(p, &pNew->aSeg[iEq], 0);
        fts5MultiIterAdvanced(p, pNew, iEq, iIter);
      }
    }
    fts5MultiIterSetEof(pNew);
    fts5AssertMultiIterSetup(p, pNew);

    if( pNew->bSkipEmpty && fts5MultiIterIsEmpty(p, pNew) ){
      fts5MultiIterNext(p, pNew, 0, 0);
    }
  }else{
    fts5MultiIterFree(p, pNew);
    *ppOut = 0;
  }
  fts5BufferFree(&buf);
}

/*
** Create an Fts5IndexIter that iterates through the doclist provided
** as the second argument.
*/
static void fts5MultiIterNew2(
  Fts5Index *p,                   /* FTS5 backend to iterate within */
  Fts5Data *pData,                /* Doclist to iterate through */
  int bDesc,                      /* True for descending rowid order */
  Fts5IndexIter **ppOut           /* New object */
){
  Fts5IndexIter *pNew;
  pNew = fts5MultiIterAlloc(p, 2);
  if( pNew ){
    Fts5SegIter *pIter = &pNew->aSeg[1];

    pIter->flags = FTS5_SEGITER_ONETERM;
    if( pData->n>0 ){
      pIter->pLeaf = pData;
................................................................................
        pNew->bRev = 1;
        pIter->flags |= FTS5_SEGITER_REVERSE;
        fts5SegIterReverseInitPage(p, pIter);
      }else{
        fts5SegIterLoadNPos(p, pIter);
      }
      pData = 0;
    }else{
      pNew->bEof = 1;
    }

    *ppOut = pNew;
  }

  fts5DataRelease(pData);
}

/*
** Return true if the iterator is at EOF or if an error has occurred. 
** False otherwise.
*/
static int fts5MultiIterEof(Fts5Index *p, Fts5IndexIter *pIter){
  assert( p->rc 
      || (pIter->aSeg[ pIter->aFirst[1].iFirst ].pLeaf==0)==pIter->bEof 
  );
  return (p->rc || pIter->bEof);
}

/*
** Return the rowid of the entry that the iterator currently points
** to. If the iterator points to EOF when this function is called the
** results are undefined.
*/
static i64 fts5MultiIterRowid(Fts5IndexIter *pIter){
  assert( pIter->aSeg[ pIter->aFirst[1].iFirst ].pLeaf );
  return pIter->aSeg[ pIter->aFirst[1].iFirst ].iRowid;
}

/*
** Move the iterator to the next entry at or following iMatch.
*/
static void fts5MultiIterNextFrom(
  Fts5Index *p, 
  Fts5IndexIter *pIter, 
  i64 iMatch
){
  while( 1 ){
    i64 iRowid;
    fts5MultiIterNext(p, pIter, 1, iMatch);
    if( fts5MultiIterEof(p, pIter) ) break;
    iRowid = fts5MultiIterRowid(pIter);
................................................................................
  }
}

/*
** Return a pointer to a buffer containing the term associated with the 
** entry that the iterator currently points to.
*/
static const u8 *fts5MultiIterTerm(Fts5IndexIter *pIter, int *pn){
  Fts5SegIter *p = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
  *pn = p->term.n;
  return p->term.p;
}

static void fts5ChunkIterate(
  Fts5Index *p,                   /* Index object */
................................................................................
}

/*
** Iterator pIter was used to iterate through the input segments of on an
** incremental merge operation. This function is called if the incremental
** merge step has finished but the input has not been completely exhausted.
*/
static void fts5TrimSegments(Fts5Index *p, Fts5IndexIter *pIter){
  int i;
  Fts5Buffer buf;
  memset(&buf, 0, sizeof(Fts5Buffer));
  for(i=0; i<pIter->nSeg; i++){
    Fts5SegIter *pSeg = &pIter->aSeg[i];
    if( pSeg->pSeg==0 ){
      /* no-op */
................................................................................
  Fts5Structure **ppStruct,       /* IN/OUT: Stucture of index */
  int iLvl,                       /* Level to read input from */
  int *pnRem                      /* Write up to this many output leaves */
){
  Fts5Structure *pStruct = *ppStruct;
  Fts5StructureLevel *pLvl = &pStruct->aLevel[iLvl];
  Fts5StructureLevel *pLvlOut;
  Fts5IndexIter *pIter = 0;       /* Iterator to read input data */
  int nRem = pnRem ? *pnRem : 0;  /* Output leaf pages left to write */
  int nInput;                     /* Number of input segments */
  Fts5SegWriter writer;           /* Writer object */
  Fts5StructureSegment *pSeg;     /* Output segment */
  Fts5Buffer term;
  int bRequireDoclistTerm = 0;    /* Doclist terminator (0x00) required */
  int bOldest;                    /* True if the output segment is the oldest */
................................................................................
      pNew = (Fts5Structure*)sqlite3Fts5MallocZero(&p->rc, nByte);
    }
  }
  if( pNew ){
    Fts5StructureLevel *pLvl;
    int nByte = nSeg * sizeof(Fts5StructureSegment);
    pNew->nLevel = pStruct->nLevel+1;
    pNew->nRef = 1;
    pNew->nWriteCounter = pStruct->nWriteCounter;
    pLvl = &pNew->aLevel[pStruct->nLevel];
    pLvl->aSeg = (Fts5StructureSegment*)sqlite3Fts5MallocZero(&p->rc, nByte);
    if( pLvl->aSeg ){
      int iLvl, iSeg;
      int iSegOut = 0;
      for(iLvl=0; iLvl<pStruct->nLevel; iLvl++){
................................................................................
** currently points to to buffer pBuf.
**
** If an error occurs, an error code is left in p->rc. It is assumed
** no error has already occurred when this function is called.
*/
static void fts5MultiIterPoslist(
  Fts5Index *p,
  Fts5IndexIter *pMulti,
  int bSz,                        /* Append a size field before the data */
  Fts5Buffer *pBuf
){
  if( p->rc==SQLITE_OK ){
    Fts5SegIter *pSeg = &pMulti->aSeg[ pMulti->aFirst[1].iFirst ];
    assert( fts5MultiIterEof(p, pMulti)==0 );

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

static void fts5SetupPrefixIter(
  Fts5Index *p,                   /* Index to read from */
  int bDesc,                      /* True for "ORDER BY rowid DESC" */
  const u8 *pToken,               /* Buffer containing prefix to match */
  int nToken,                     /* Size of buffer pToken in bytes */
  Fts5IndexIter **ppIter       /* OUT: New iterator */
){
  Fts5Structure *pStruct;
  Fts5Buffer *aBuf;
  const int nBuf = 32;

  aBuf = (Fts5Buffer*)fts5IdxMalloc(p, sizeof(Fts5Buffer)*nBuf);
  pStruct = fts5StructureRead(p);

  if( aBuf && pStruct ){
    const int flags = FTS5INDEX_QUERY_SCAN;
    int i;
    i64 iLastRowid = 0;
    Fts5IndexIter *p1 = 0;     /* Iterator used to gather data from index */
    Fts5Data *pData;
    Fts5Buffer doclist;

    memset(&doclist, 0, sizeof(doclist));
    for(fts5MultiIterNew(p, pStruct, 1, flags, pToken, nToken, -1, 0, &p1);
        fts5MultiIterEof(p, p1)==0;
        fts5MultiIterNext(p, p1, 0, 0)
................................................................................
    fts5MultiIterFree(p, p1);

    pData = fts5IdxMalloc(p, sizeof(Fts5Data) + doclist.n);
    if( pData ){
      pData->p = (u8*)&pData[1];
      pData->n = doclist.n;
      memcpy(pData->p, doclist.p, doclist.n);
      fts5MultiIterNew2(p, pData, bDesc, ppIter);
    }
    fts5BufferFree(&doclist);
  }

  fts5StructureRelease(pStruct);
  sqlite3_free(aBuf);
}
................................................................................
int sqlite3Fts5IndexQuery(
  Fts5Index *p,                   /* FTS index to query */
  const char *pToken, int nToken, /* Token (or prefix) to query for */
  int flags,                      /* Mask of FTS5INDEX_QUERY_X flags */
  Fts5IndexIter **ppIter          /* OUT: New iterator object */
){
  Fts5Config *pConfig = p->pConfig;
  Fts5IndexIter *pRet = 0;
  int iIdx = 0;
  Fts5Buffer buf = {0, 0, 0};

  /* If the QUERY_SCAN flag is set, all other flags must be clear. */
  assert( (flags & FTS5INDEX_QUERY_SCAN)==0
       || (flags & FTS5INDEX_QUERY_SCAN)==FTS5INDEX_QUERY_SCAN
  );

  if( sqlite3Fts5BufferGrow(&p->rc, &buf, nToken+1)==0 ){
    memcpy(&buf.p[1], pToken, nToken);


#ifdef SQLITE_DEBUG
    if( flags & FTS5INDEX_QUERY_TEST_NOIDX ){
      assert( flags & FTS5INDEX_QUERY_PREFIX );
      iIdx = 1+pConfig->nPrefix;
    }else
#endif
    if( flags & FTS5INDEX_QUERY_PREFIX ){
      int nChar = fts5IndexCharlen(pToken, nToken);
      for(iIdx=1; iIdx<=pConfig->nPrefix; iIdx++){
        if( pConfig->aPrefix[iIdx-1]==nChar ) break;
      }
    }




    if( iIdx<=pConfig->nPrefix ){
      Fts5Structure *pStruct = fts5StructureRead(p);
      buf.p[0] = FTS5_MAIN_PREFIX + iIdx;

      if( pStruct ){

        fts5MultiIterNew(p, pStruct, 1, flags, buf.p, nToken+1, -1, 0, &pRet);

        fts5StructureRelease(pStruct);
      }
    }else{
      int bDesc = (flags & FTS5INDEX_QUERY_DESC)!=0;
      buf.p[0] = FTS5_MAIN_PREFIX;
      fts5SetupPrefixIter(p, bDesc, buf.p, nToken+1, &pRet);
    }


    if( p->rc ){
      sqlite3Fts5IterClose(pRet);
      pRet = 0;
      fts5CloseReader(p);
    }
    *ppIter = pRet;
    sqlite3Fts5BufferFree(&buf);
  }
  return fts5IndexReturn(p);
}

/*
** Return true if the iterator passed as the only argument is at EOF.
*/
int sqlite3Fts5IterEof(Fts5IndexIter *pIter){
  assert( pIter->pIndex->rc==SQLITE_OK );
  return pIter->bEof;
}

/*
** Move to the next matching rowid. 
*/
int sqlite3Fts5IterNext(Fts5IndexIter *pIter){
  assert( pIter->pIndex->rc==SQLITE_OK );
  fts5MultiIterNext(pIter->pIndex, pIter, 0, 0);
  return fts5IndexReturn(pIter->pIndex);
}

/*
** Move to the next matching term/rowid. Used by the fts5vocab module.
*/
int sqlite3Fts5IterNextScan(Fts5IndexIter *pIter){
  Fts5Index *p = pIter->pIndex;


  assert( pIter->pIndex->rc==SQLITE_OK );


  fts5MultiIterNext(p, pIter, 0, 0);
  if( p->rc==SQLITE_OK ){
    Fts5SegIter *pSeg = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
    if( pSeg->pLeaf && pSeg->term.p[0]!=FTS5_MAIN_PREFIX ){
      fts5DataRelease(pSeg->pLeaf);
      pSeg->pLeaf = 0;
      pIter->bEof = 1;
    }
  }

  return fts5IndexReturn(pIter->pIndex);
}

/*
** Move to the next matching rowid that occurs at or after iMatch. The
** definition of "at or after" depends on whether this iterator iterates
** in ascending or descending rowid order.
*/
int sqlite3Fts5IterNextFrom(Fts5IndexIter *pIter, i64 iMatch){
  fts5MultiIterNextFrom(pIter->pIndex, pIter, iMatch);
  return fts5IndexReturn(pIter->pIndex);
}

/*
** Return the current rowid.
*/
i64 sqlite3Fts5IterRowid(Fts5IndexIter *pIter){
  return fts5MultiIterRowid(pIter);
}

/*
** Return the current term.
*/
const char *sqlite3Fts5IterTerm(Fts5IndexIter *pIter, int *pn){
  int n;
  const char *z = (const char*)fts5MultiIterTerm(pIter, &n);
  *pn = n-1;
  return &z[1];
}


/*
** Return a pointer to a buffer containing a copy of the position list for
................................................................................
*/
int sqlite3Fts5IterPoslist(
  Fts5IndexIter *pIter, 
  const u8 **pp,                  /* OUT: Pointer to position-list data */
  int *pn,                        /* OUT: Size of position-list in bytes */
  i64 *piRowid                    /* OUT: Current rowid */
){

  Fts5SegIter *pSeg = &pIter->aSeg[ pIter->aFirst[1].iFirst ];
  assert( pIter->pIndex->rc==SQLITE_OK );
  *piRowid = pSeg->iRowid;
  *pn = pSeg->nPos;
  if( pSeg->iLeafOffset+pSeg->nPos <= pSeg->pLeaf->n ){
    *pp = &pSeg->pLeaf->p[pSeg->iLeafOffset];
  }else{
    fts5BufferZero(&pIter->poslist);
................................................................................
/*
** This function is similar to sqlite3Fts5IterPoslist(), except that it
** copies the position list into the buffer supplied as the second 
** argument.
*/
int sqlite3Fts5IterPoslistBuffer(Fts5IndexIter *pIter, Fts5Buffer *pBuf){
  Fts5Index *p = pIter->pIndex;


  assert( p->rc==SQLITE_OK );
  fts5BufferZero(pBuf);
  fts5MultiIterPoslist(p, pIter, 0, pBuf);
  return fts5IndexReturn(p);
}

/*
** Close an iterator opened by an earlier call to sqlite3Fts5IndexQuery().
*/
void sqlite3Fts5IterClose(Fts5IndexIter *pIter){
  if( pIter ){
    Fts5Index *pIndex = pIter->pIndex;
    fts5MultiIterFree(pIter->pIndex, pIter);


    fts5CloseReader(pIndex);

  }
}

/*
** Read the "averages" record into the buffer supplied as the second 
** argument. Return SQLITE_OK if successful, or an SQLite error code
** if an error occurs.
................................................................................
  }else
  if( rc==SQLITE_OK && (pPrev->n!=n || memcmp(pPrev->p, z, n)) ){
    u64 cksum3 = *pCksum;
    const char *zTerm = (const char*)&pPrev->p[1];  /* term sans prefix-byte */
    int nTerm = pPrev->n-1;            /* Size of zTerm in bytes */
    int iIdx = (pPrev->p[0] - FTS5_MAIN_PREFIX);
    int flags = (iIdx==0 ? 0 : FTS5INDEX_QUERY_PREFIX);

    u64 ck1 = 0;
    u64 ck2 = 0;

    /* Check that the results returned for ASC and DESC queries are
    ** the same. If not, call this corruption.  */
    rc = fts5QueryCksum(p, iIdx, zTerm, nTerm, flags, &ck1);
    if( rc==SQLITE_OK ){
................................................................................
** checksum does not match. Return SQLITE_OK if all checks pass without
** error, or some other SQLite error code if another error (e.g. OOM)
** occurs.
*/
int sqlite3Fts5IndexIntegrityCheck(Fts5Index *p, u64 cksum){
  u64 cksum2 = 0;                 /* Checksum based on contents of indexes */
  Fts5Buffer poslist = {0,0,0};   /* Buffer used to hold a poslist */
  Fts5IndexIter *pIter;           /* Used to iterate through entire index */
  Fts5Structure *pStruct;         /* Index structure */

  /* Used by extra internal tests only run if NDEBUG is not defined */
  u64 cksum3 = 0;                 /* Checksum based on contents of indexes */
  Fts5Buffer term = {0,0,0};      /* Buffer used to hold most recent term */
  
  /* Load the FTS index structure */
................................................................................
  ){
    int n;                      /* Size of term in bytes */
    i64 iPos = 0;               /* Position read from poslist */
    int iOff = 0;               /* Offset within poslist */
    i64 iRowid = fts5MultiIterRowid(pIter);
    char *z = (char*)fts5MultiIterTerm(pIter, &n);

    /* If this is a new term, query for it. Update cksum3 with the results. */
    fts5TestTerm(p, &term, z, n, cksum2, &cksum3);

    poslist.n = 0;
    fts5MultiIterPoslist(p, pIter, 0, &poslist);
    while( 0==sqlite3Fts5PoslistNext64(poslist.p, poslist.n, &iOff, &iPos) ){
      int iCol = FTS5_POS2COLUMN(iPos);
      int iTokOff = FTS5_POS2OFFSET(iPos);
      cksum2 ^= fts5IndexEntryCksum(iRowid, iCol, iTokOff, -1, z, n);
    }



  }
  fts5TestTerm(p, &term, 0, 0, cksum2, &cksum3);

  fts5MultiIterFree(p, pIter);
  if( p->rc==SQLITE_OK && cksum!=cksum2 ) p->rc = FTS5_CORRUPT;

  fts5StructureRelease(pStruct);
................................................................................
  Fts5Structure *p
){
  int iLvl, iSeg;                 /* Iterate through levels, segments */

  for(iLvl=0; iLvl<p->nLevel; iLvl++){
    Fts5StructureLevel *pLvl = &p->aLevel[iLvl];
    sqlite3Fts5BufferAppendPrintf(pRc, pBuf, 
        " {lvl=%d nMerge=%d nSeg=%d", iLvl, pLvl->nMerge, pLvl->nSeg
    );
    for(iSeg=0; iSeg<pLvl->nSeg; iSeg++){
      Fts5StructureSegment *pSeg = &pLvl->aSeg[iSeg];
      sqlite3Fts5BufferAppendPrintf(pRc, pBuf, 
          " {id=%d h=%d leaves=%d..%d}", pSeg->iSegid, pSeg->nHeight, 
          pSeg->pgnoFirst, pSeg->pgnoLast
      );

#define FTS5_BI_ORDER_DESC   0x0080

/*
** Values for Fts5Cursor.csrflags
*/
#define FTS5CSR_REQUIRE_CONTENT   0x01
#define FTS5CSR_REQUIRE_DOCSIZE   0x02

#define FTS5CSR_EOF               0x04
#define FTS5CSR_FREE_ZRANK        0x08
#define FTS5CSR_REQUIRE_RESEEK    0x10

#define BitFlagAllTest(x,y) (((x) & (y))==(y))
#define BitFlagTest(x,y)    (((x) & (y))!=0)

/*
** Constants for the largest and smallest possible 64-bit signed integers.
** These are copied from sqliteInt.h.
*/
#ifndef SQLITE_AMALGAMATION
# define LARGEST_INT64  (0xffffffff|(((i64)0x7fffffff)<<32))
# define SMALLEST_INT64 (((i64)-1) - LARGEST_INT64)
#endif

/*
** Macros to Set(), Clear() and Test() cursor flags.
*/
#define CsrFlagSet(pCsr, flag)   ((pCsr)->csrflags |= (flag))
#define CsrFlagClear(pCsr, flag) ((pCsr)->csrflags &= ~(flag))
#define CsrFlagTest(pCsr, flag)  ((pCsr)->csrflags & (flag))
................................................................................
){
  return fts5InitVtab(1, db, pAux, argc, argv, ppVtab, pzErr);
}

/*
** The different query plans.
*/
#define FTS5_PLAN_SCAN           1       /* No usable constraint */
#define FTS5_PLAN_MATCH          2       /* (<tbl> MATCH ?) */

#define FTS5_PLAN_SORTED_MATCH   3       /* (<tbl> MATCH ? ORDER BY rank) */

#define FTS5_PLAN_ROWID          4       /* (rowid = ?) */
#define FTS5_PLAN_SOURCE         5       /* A source cursor for SORTED_MATCH */
#define FTS5_PLAN_SPECIAL        6       /* An internal query */

/*
** Implementation of the xBestIndex method for FTS5 tables. Within the 
** WHERE constraint, it searches for the following:
**
**   1. A MATCH constraint against the special column.
**   2. A MATCH constraint against the "rank" column.
................................................................................

/*
** This function is called after the cursor passed as the only argument
** is moved to point at a different row. It clears all cached data 
** specific to the previous row stored by the cursor object.
*/
static void fts5CsrNewrow(Fts5Cursor *pCsr){

  CsrFlagSet(pCsr, FTS5CSR_REQUIRE_CONTENT | FTS5CSR_REQUIRE_DOCSIZE );
  sqlite3_free(pCsr->aInst);
  pCsr->aInst = 0;
  pCsr->nInstCount = 0;

}

/*
** Close the cursor.  For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts5CloseMethod(sqlite3_vtab_cursor *pCursor){
................................................................................
  if( pCursor ){
    Fts5Table *pTab = (Fts5Table*)(pCursor->pVtab);
    Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
    Fts5Cursor **pp;
    Fts5Auxdata *pData;
    Fts5Auxdata *pNext;

    fts5CsrNewrow(pCsr);
    if( pCsr->pStmt ){
      int eStmt = fts5StmtType(pCsr);
      sqlite3Fts5StorageStmtRelease(pTab->pStorage, eStmt, pCsr->pStmt);
    }
    if( pCsr->pSorter ){
      Fts5Sorter *pSorter = pCsr->pSorter;
      sqlite3_finalize(pSorter->pStmt);
................................................................................
**
** Return SQLITE_OK if nothing goes wrong.  SQLITE_OK is returned
** even if we reach end-of-file.  The fts5EofMethod() will be called
** subsequently to determine whether or not an EOF was hit.
*/
static int fts5NextMethod(sqlite3_vtab_cursor *pCursor){
  Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
  int ePlan = pCsr->ePlan;
  int bSkip = 0;
  int rc;



  if( (rc = fts5CursorReseek(pCsr, &bSkip)) || bSkip ) return rc;

  switch( ePlan ){
    case FTS5_PLAN_MATCH:
    case FTS5_PLAN_SOURCE:
      rc = sqlite3Fts5ExprNext(pCsr->pExpr, pCsr->iLastRowid);
      if( sqlite3Fts5ExprEof(pCsr->pExpr) ){
        CsrFlagSet(pCsr, FTS5CSR_EOF);
      }
      fts5CsrNewrow(pCsr);
      break;


    case FTS5_PLAN_SPECIAL: {
      CsrFlagSet(pCsr, FTS5CSR_EOF);
      break;
    }

    case FTS5_PLAN_SORTED_MATCH: {
      rc = fts5SorterNext(pCsr);
      break;
    }

    default:
      rc = sqlite3_step(pCsr->pStmt);
      if( rc!=SQLITE_ROW ){
        CsrFlagSet(pCsr, FTS5CSR_EOF);
        rc = sqlite3_reset(pCsr->pStmt);
      }else{
        rc = SQLITE_OK;
      }
      break;

  }
  
  return rc;
}

static int fts5CursorFirstSorted(Fts5Table *pTab, Fts5Cursor *pCsr, int bDesc){
  Fts5Config *pConfig = pTab->pConfig;
................................................................................
/*
** Ensure that the Fts5Cursor.nInstCount and aInst[] variables are populated
** correctly for the current view. Return SQLITE_OK if successful, or an
** SQLite error code otherwise.
*/
static int fts5CacheInstArray(Fts5Cursor *pCsr){
  int rc = SQLITE_OK;
  if( pCsr->aInst==0 ){
    Fts5PoslistReader *aIter;     /* One iterator for each phrase */
    int nIter;                    /* Number of iterators/phrases */
    int nByte;
    
    nIter = sqlite3Fts5ExprPhraseCount(pCsr->pExpr);
    nByte = sizeof(Fts5PoslistReader) * nIter;
    aIter = (Fts5PoslistReader*)sqlite3Fts5MallocZero(&rc, nByte);
................................................................................
        aInst = &((int*)buf.p)[3 * (nInst-1)];
        aInst[0] = iBest;
        aInst[1] = FTS5_POS2COLUMN(aIter[iBest].iPos);
        aInst[2] = FTS5_POS2OFFSET(aIter[iBest].iPos);
        sqlite3Fts5PoslistReaderNext(&aIter[iBest]);
      }


      pCsr->aInst = (int*)buf.p;
      pCsr->nInstCount = nInst;
      sqlite3_free(aIter);

    }
  }
  return rc;
}

static int fts5ApiInstCount(Fts5Context *pCtx, int *pnInst){
  Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
................................................................................
  Fts5Global *pGlobal = (Fts5Global*)sqlite3_user_data(pCtx);
  char buf[8];
  assert( nArg==0 );
  assert( sizeof(buf)>=sizeof(pGlobal) );
  memcpy(buf, (void*)&pGlobal, sizeof(pGlobal));
  sqlite3_result_blob(pCtx, buf, sizeof(pGlobal), SQLITE_TRANSIENT);
}













#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_fts5_init(
  sqlite3 *db,
  char **pzErrMsg,
................................................................................
    if( rc==SQLITE_OK ) rc = sqlite3Fts5AuxInit(&pGlobal->api);
    if( rc==SQLITE_OK ) rc = sqlite3Fts5TokenizerInit(&pGlobal->api);
    if( rc==SQLITE_OK ) rc = sqlite3Fts5VocabInit(pGlobal, db);
    if( rc==SQLITE_OK ){
      rc = sqlite3_create_function(
          db, "fts5", 0, SQLITE_UTF8, p, fts5Fts5Func, 0, 0
      );





    }
  }
  return rc;
}

#ifdef _WIN32
__declspec(dllexport)

#define FTS5_BI_ORDER_DESC   0x0080

/*
** Values for Fts5Cursor.csrflags
*/
#define FTS5CSR_REQUIRE_CONTENT   0x01
#define FTS5CSR_REQUIRE_DOCSIZE   0x02
#define FTS5CSR_REQUIRE_INST      0x04
#define FTS5CSR_EOF               0x08
#define FTS5CSR_FREE_ZRANK        0x10
#define FTS5CSR_REQUIRE_RESEEK    0x20

#define BitFlagAllTest(x,y) (((x) & (y))==(y))
#define BitFlagTest(x,y)    (((x) & (y))!=0)










/*
** Macros to Set(), Clear() and Test() cursor flags.
*/
#define CsrFlagSet(pCsr, flag)   ((pCsr)->csrflags |= (flag))
#define CsrFlagClear(pCsr, flag) ((pCsr)->csrflags &= ~(flag))
#define CsrFlagTest(pCsr, flag)  ((pCsr)->csrflags & (flag))
................................................................................
){
  return fts5InitVtab(1, db, pAux, argc, argv, ppVtab, pzErr);
}

/*
** The different query plans.
*/
#define FTS5_PLAN_MATCH          0       /* (<tbl> MATCH ?) */
#define FTS5_PLAN_SOURCE         1       /* A source cursor for SORTED_MATCH */
#define FTS5_PLAN_SPECIAL        2       /* An internal query */
#define FTS5_PLAN_SORTED_MATCH   3       /* (<tbl> MATCH ? ORDER BY rank) */
#define FTS5_PLAN_SCAN           4       /* No usable constraint */
#define FTS5_PLAN_ROWID          5       /* (rowid = ?) */



/*
** Implementation of the xBestIndex method for FTS5 tables. Within the 
** WHERE constraint, it searches for the following:
**
**   1. A MATCH constraint against the special column.
**   2. A MATCH constraint against the "rank" column.
................................................................................

/*
** This function is called after the cursor passed as the only argument
** is moved to point at a different row. It clears all cached data 
** specific to the previous row stored by the cursor object.
*/
static void fts5CsrNewrow(Fts5Cursor *pCsr){
  CsrFlagSet(pCsr, 
      FTS5CSR_REQUIRE_CONTENT 

    | FTS5CSR_REQUIRE_DOCSIZE 
    | FTS5CSR_REQUIRE_INST 
  );
}

/*
** Close the cursor.  For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts5CloseMethod(sqlite3_vtab_cursor *pCursor){
................................................................................
  if( pCursor ){
    Fts5Table *pTab = (Fts5Table*)(pCursor->pVtab);
    Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
    Fts5Cursor **pp;
    Fts5Auxdata *pData;
    Fts5Auxdata *pNext;

    sqlite3_free(pCsr->aInst);
    if( pCsr->pStmt ){
      int eStmt = fts5StmtType(pCsr);
      sqlite3Fts5StorageStmtRelease(pTab->pStorage, eStmt, pCsr->pStmt);
    }
    if( pCsr->pSorter ){
      Fts5Sorter *pSorter = pCsr->pSorter;
      sqlite3_finalize(pSorter->pStmt);
................................................................................
**
** Return SQLITE_OK if nothing goes wrong.  SQLITE_OK is returned
** even if we reach end-of-file.  The fts5EofMethod() will be called
** subsequently to determine whether or not an EOF was hit.
*/
static int fts5NextMethod(sqlite3_vtab_cursor *pCursor){
  Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;


  int rc;

  assert( (pCsr->ePlan<2)==
          (pCsr->ePlan==FTS5_PLAN_MATCH || pCsr->ePlan==FTS5_PLAN_SOURCE) 
  );

  if( pCsr->ePlan<2 ){
    int bSkip = 0;
    if( (rc = fts5CursorReseek(pCsr, &bSkip)) || bSkip ) return rc;
    rc = sqlite3Fts5ExprNext(pCsr->pExpr, pCsr->iLastRowid);
    if( sqlite3Fts5ExprEof(pCsr->pExpr) ){
      CsrFlagSet(pCsr, FTS5CSR_EOF);
    }
    fts5CsrNewrow(pCsr);
  }else{

    switch( pCsr->ePlan ){
      case FTS5_PLAN_SPECIAL: {
        CsrFlagSet(pCsr, FTS5CSR_EOF);
        break;
      }
  
      case FTS5_PLAN_SORTED_MATCH: {
        rc = fts5SorterNext(pCsr);
        break;
      }
  
      default:
        rc = sqlite3_step(pCsr->pStmt);
        if( rc!=SQLITE_ROW ){
          CsrFlagSet(pCsr, FTS5CSR_EOF);
          rc = sqlite3_reset(pCsr->pStmt);
        }else{
          rc = SQLITE_OK;
        }
        break;
    }
  }
  
  return rc;
}

static int fts5CursorFirstSorted(Fts5Table *pTab, Fts5Cursor *pCsr, int bDesc){
  Fts5Config *pConfig = pTab->pConfig;
................................................................................
/*
** Ensure that the Fts5Cursor.nInstCount and aInst[] variables are populated
** correctly for the current view. Return SQLITE_OK if successful, or an
** SQLite error code otherwise.
*/
static int fts5CacheInstArray(Fts5Cursor *pCsr){
  int rc = SQLITE_OK;
  if( CsrFlagTest(pCsr, FTS5CSR_REQUIRE_INST) ){
    Fts5PoslistReader *aIter;     /* One iterator for each phrase */
    int nIter;                    /* Number of iterators/phrases */
    int nByte;
    
    nIter = sqlite3Fts5ExprPhraseCount(pCsr->pExpr);
    nByte = sizeof(Fts5PoslistReader) * nIter;
    aIter = (Fts5PoslistReader*)sqlite3Fts5MallocZero(&rc, nByte);
................................................................................
        aInst = &((int*)buf.p)[3 * (nInst-1)];
        aInst[0] = iBest;
        aInst[1] = FTS5_POS2COLUMN(aIter[iBest].iPos);
        aInst[2] = FTS5_POS2OFFSET(aIter[iBest].iPos);
        sqlite3Fts5PoslistReaderNext(&aIter[iBest]);
      }

      sqlite3_free(pCsr->aInst);
      pCsr->aInst = (int*)buf.p;
      pCsr->nInstCount = nInst;
      sqlite3_free(aIter);
      CsrFlagClear(pCsr, FTS5CSR_REQUIRE_INST);
    }
  }
  return rc;
}

static int fts5ApiInstCount(Fts5Context *pCtx, int *pnInst){
  Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
................................................................................
  Fts5Global *pGlobal = (Fts5Global*)sqlite3_user_data(pCtx);
  char buf[8];
  assert( nArg==0 );
  assert( sizeof(buf)>=sizeof(pGlobal) );
  memcpy(buf, (void*)&pGlobal, sizeof(pGlobal));
  sqlite3_result_blob(pCtx, buf, sizeof(pGlobal), SQLITE_TRANSIENT);
}

/*
** Implementation of fts5_source_id() function.
*/
static void fts5SourceIdFunc(
  sqlite3_context *pCtx,          /* Function call context */
  int nArg,                       /* Number of args */
  sqlite3_value **apVal           /* Function arguments */
){
  assert( nArg==0 );
  sqlite3_result_text(pCtx, "--FTS5-SOURCE-ID--", -1, SQLITE_TRANSIENT);
}

#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_fts5_init(
  sqlite3 *db,
  char **pzErrMsg,
................................................................................
    if( rc==SQLITE_OK ) rc = sqlite3Fts5AuxInit(&pGlobal->api);
    if( rc==SQLITE_OK ) rc = sqlite3Fts5TokenizerInit(&pGlobal->api);
    if( rc==SQLITE_OK ) rc = sqlite3Fts5VocabInit(pGlobal, db);
    if( rc==SQLITE_OK ){
      rc = sqlite3_create_function(
          db, "fts5", 0, SQLITE_UTF8, p, fts5Fts5Func, 0, 0
      );
    }
    if( rc==SQLITE_OK ){
      rc = sqlite3_create_function(
          db, "fts5_source_id", 0, SQLITE_UTF8, p, fts5SourceIdFunc, 0, 0
      );
    }
  }
  return rc;
}

#ifdef _WIN32
__declspec(dllexport)

  }
}

proc fts5_level_segs {tbl} {
  set sql "SELECT fts5_decode(rowid,block) aS r FROM ${tbl}_data WHERE rowid=10"
  set ret [list]
  foreach L [lrange [db one $sql] 1 end] {
    lappend ret [expr [llength $L] - 2]
  }
  set ret
} 

proc fts5_level_segids {tbl} {
  set sql "SELECT fts5_decode(rowid,block) aS r FROM ${tbl}_data WHERE rowid=10"
  set ret [list]
  foreach L [lrange [db one $sql] 1 end] {
    set lvl [list]
    foreach S [lrange $L 2 end] {
      regexp {id=([1234567890]*)} $S -> segid
      lappend lvl $segid
    }
    lappend ret $lvl
  }
  set ret
}

  }
}

proc fts5_level_segs {tbl} {
  set sql "SELECT fts5_decode(rowid,block) aS r FROM ${tbl}_data WHERE rowid=10"
  set ret [list]
  foreach L [lrange [db one $sql] 1 end] {
    lappend ret [expr [llength $L] - 3]
  }
  set ret
} 

proc fts5_level_segids {tbl} {
  set sql "SELECT fts5_decode(rowid,block) aS r FROM ${tbl}_data WHERE rowid=10"
  set ret [list]
  foreach L [lrange [db one $sql] 1 end] {
    set lvl [list]
    foreach S [lrange $L 3 end] {
      regexp {id=([1234567890]*)} $S -> segid
      lappend lvl $segid
    }
    lappend ret $lvl
  }
  set ret
}

  CREATE VIRTUAL TABLE t1 USING fts5(x,y);
}
do_execsql_test 2.1 {
  INSERT INTO t1 VALUES('a b c', 'd e f');
}
do_test 2.2 {
  execsql { SELECT fts5_decode(id, block) FROM t1_data WHERE id==10 }
} {/{\(structure\) {lvl=0 nMerge=0 {id=[0123456789]* h=1 leaves=1..1}}}/}










do_execsql_test 2.3 {
  INSERT INTO t1(t1) VALUES('integrity-check');
}

#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 3.0 {
................................................................................
      set z [doc]
      set rowid [expr int(rand() * 100)]
      execsql { REPLACE INTO t1(rowid,x,y,z) VALUES($rowid, $x, $y, $z) }
    }
    execsql { INSERT INTO t1(t1) VALUES('integrity-check'); }
  } {}
}
#db eval {SELECT rowid, fts5_decode(rowid, block) aS r FROM t1_data} {puts $r}
#exit

#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 8.0 {
  CREATE VIRTUAL TABLE t1 USING fts5(x, prefix="1,2,3");
  INSERT INTO t1(t1, rank) VALUES('pgsz', 32);

  CREATE VIRTUAL TABLE t1 USING fts5(x,y);
}
do_execsql_test 2.1 {
  INSERT INTO t1 VALUES('a b c', 'd e f');
}
do_test 2.2 {
  execsql { SELECT fts5_decode(id, block) FROM t1_data WHERE id==10 }
} {/{\(structure\) {lvl=0 nMerge=0 nSeg=1 {id=[0123456789]* h=1 leaves=1..1}}}/}

foreach w {a b c d e f} {
  do_execsql_test 2.3.$w.asc {
    SELECT rowid FROM t1 WHERE t1 MATCH $w;
  } {1}
  do_execsql_test 2.3.$w.desc {
    SELECT rowid FROM t1 WHERE t1 MATCH $w ORDER BY rowid DESC;
  } {1}
}

do_execsql_test 2.4 {
  INSERT INTO t1(t1) VALUES('integrity-check');
}

#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 3.0 {
................................................................................
      set z [doc]
      set rowid [expr int(rand() * 100)]
      execsql { REPLACE INTO t1(rowid,x,y,z) VALUES($rowid, $x, $y, $z) }
    }
    execsql { INSERT INTO t1(t1) VALUES('integrity-check'); }
  } {}
}



#-------------------------------------------------------------------------
#
reset_db
do_execsql_test 8.0 {
  CREATE VIRTUAL TABLE t1 USING fts5(x, prefix="1,2,3");
  INSERT INTO t1(t1, rank) VALUES('pgsz', 32);

  do_test $tn2.1.1 {
    foreach {id x y} $data {
      execsql { INSERT INTO xx(rowid, x, y) VALUES($id, $x, $y) }
    }
    execsql { INSERT INTO xx(xx) VALUES('integrity-check') }
  } {}


  #-------------------------------------------------------------------------
  # Test phrase queries.
  #
  foreach {tn phrase} {
    1 "o"
    2 "b q"

  do_test $tn2.1.1 {
    foreach {id x y} $data {
      execsql { INSERT INTO xx(rowid, x, y) VALUES($id, $x, $y) }
    }
    execsql { INSERT INTO xx(xx) VALUES('integrity-check') }
  } {}


  #-------------------------------------------------------------------------
  # Test phrase queries.
  #
  foreach {tn phrase} {
    1 "o"
    2 "b q"

          break
        }
      }
      if {$bMatch} { lappend ret $rowid }
    }
    return $ret
  }
  

  foreach {bAsc sql} {
    0 {SELECT rowid FROM t1 WHERE t1 MATCH $prefix ORDER BY rowid DESC}
    1 {SELECT rowid FROM t1 WHERE t1 MATCH $prefix}
  } {
    foreach {tn prefix} {
      1  {a*} 2 {ab*} 3 {abc*} 4 {abcd*} 5 {abcde*} 
      6  {f*} 7 {fg*} 8 {fgh*} 9 {fghi*} 10 {fghij*}
      11 {k*} 12 {kl*} 13 {klm*} 14 {klmn*} 15 {klmno*}
      16 {p*} 17 {pq*} 18 {pqr*} 19 {pqrs*} 20 {pqrst*}
      21 {u*} 22 {uv*} 23 {uvw*} 24 {uvwx*} 25 {uvwxy*} 26 {uvwxyz*}

          break
        }
      }
      if {$bMatch} { lappend ret $rowid }
    }
    return $ret
  }

  
  foreach {bAsc sql} {
    1 {SELECT rowid FROM t1 WHERE t1 MATCH $prefix}
    0 {SELECT rowid FROM t1 WHERE t1 MATCH $prefix ORDER BY rowid DESC}
  } {
    foreach {tn prefix} {
      1  {a*} 2 {ab*} 3 {abc*} 4 {abcd*} 5 {abcde*} 
      6  {f*} 7 {fg*} 8 {fgh*} 9 {fghi*} 10 {fghij*}
      11 {k*} 12 {kl*} 13 {klm*} 14 {klmn*} 15 {klmno*}
      16 {p*} 17 {pq*} 18 {pqr*} 19 {pqrs*} 20 {pqrst*}
      21 {u*} 22 {uv*} 23 {uvw*} 24 {uvwx*} 25 {uvwxy*} 26 {uvwxyz*}

} {-56 -22 -11}

do_execsql_test 2.3 {
  ROLLBACK;
  SELECT rowid FROM yy WHERE yy MATCH 'a + b + c';
} {-56 -22}



















finish_test

} {-56 -22 -11}

do_execsql_test 2.3 {
  ROLLBACK;
  SELECT rowid FROM yy WHERE yy MATCH 'a + b + c';
} {-56 -22}

#-------------------------------------------------------------------------

do_execsql_test 3.1 {
  CREATE VIRTUAL TABLE abc USING fts5(a);
  INSERT INTO abc(rowid, a) VALUES(1, 'a');
  BEGIN;
    INSERT INTO abc(rowid, a) VALUES(2, 'a');
}
breakpoint
do_execsql_test 3.2 {
    SELECT rowid FROM abc WHERE abc MATCH 'a';
} {1 2}

do_execsql_test 3.3 {
  COMMIT;
  SELECT rowid FROM abc WHERE abc MATCH 'a';
} {1 2}

finish_test

set res [db one {SELECT count(*) FROM x1_data}]
do_execsql_test 2.3 {
  SELECT count(fts5_decode(rowid, block)) FROM x1_data;
} $res
do_execsql_test 2.4 {
  UPDATE x1_data SET block = X'';
  SELECT count(fts5_decode(rowid, block)) FROM x1_data;

} $res

do_execsql_test 2.5 {
  INSERT INTO x1(x1, rank) VALUES('pgsz', 1024);
  INSERT INTO x1(x1) VALUES('rebuild');
}

set res [db one {SELECT count(*) FROM x1_data}]
do_execsql_test 2.6 {
  SELECT count(fts5_decode(rowid, block)) FROM x1_data;
} $res


do_execsql_test 2.7 {
  UPDATE x1_data SET block = X'';
  SELECT count(fts5_decode(rowid, block)) FROM x1_data;
} $res

#-------------------------------------------------------------------------
# Tests with very large tokens.
#
set strlist [list \
  "[string repeat x 400]"                       \
  "[string repeat x 300][string repeat w 100]"  \

set res [db one {SELECT count(*) FROM x1_data}]
do_execsql_test 2.3 {
  SELECT count(fts5_decode(rowid, block)) FROM x1_data;
} $res
do_execsql_test 2.4 {
  UPDATE x1_data SET block = X'';
  -- SELECT count(fts5_decode(rowid, block)) FROM x1_data;
  SELECT count(*) FROM x1_data;
} $res

do_execsql_test 2.5 {
  INSERT INTO x1(x1, rank) VALUES('pgsz', 1024);
  INSERT INTO x1(x1) VALUES('rebuild');
}

set res [db one {SELECT count(*) FROM x1_data}]
do_execsql_test 2.6 {
  SELECT count(fts5_decode(rowid, block)) FROM x1_data;
} $res

# This is really a corruption test...
#do_execsql_test 2.7 {
#  UPDATE x1_data SET block = X'';
#  SELECT count(fts5_decode(rowid, block)) FROM x1_data;
#} $res

#-------------------------------------------------------------------------
# Tests with very large tokens.
#
set strlist [list \
  "[string repeat x 400]"                       \
  "[string repeat x 300][string repeat w 100]"  \

proc do_isspace_test {tn tokenizer lCp} {
  set whitespace [format [string repeat %c [llength $lCp]] {*}$lCp] 
  set txt "${whitespace}hello${whitespace}world${whitespace}"
  uplevel [list do_test $tn [list do_tokenize $tokenizer $txt] {hello world}]
}

set tokenizers [list unicode61]
ifcapable icu { lappend tokenizers icu }

# Some tests to check that the tokenizers can both identify white-space 
# codepoints. All codepoints tested below are of type "Zs" in the
# UnicodeData.txt file.
foreach T $tokenizers {
  do_isspace_test 6.$T.1 $T    32
  do_isspace_test 6.$T.2 $T    160

proc do_isspace_test {tn tokenizer lCp} {
  set whitespace [format [string repeat %c [llength $lCp]] {*}$lCp] 
  set txt "${whitespace}hello${whitespace}world${whitespace}"
  uplevel [list do_test $tn [list do_tokenize $tokenizer $txt] {hello world}]
}

set tokenizers [list unicode61]
#ifcapable icu { lappend tokenizers icu }

# Some tests to check that the tokenizers can both identify white-space 
# codepoints. All codepoints tested below are of type "Zs" in the
# UnicodeData.txt file.
foreach T $tokenizers {
  do_isspace_test 6.$T.1 $T    32
  do_isspace_test 6.$T.2 $T    160

do_test 1.5 {
  db close
  sqlite3 db test.db
  catchsql { SELECT * FROM t1 WHERE t1 MATCH 'a' }
} {1 {invalid fts5 file format (found 3, expected 2) - run 'rebuild'}}

breakpoint
do_test 1.6 {
  db close
  sqlite3 db test.db
  catchsql { INSERT INTO t1 VALUES('x y z') }
} {1 {invalid fts5 file format (found 3, expected 2) - run 'rebuild'}}

do_test 1.7 {

do_test 1.5 {
  db close
  sqlite3 db test.db
  catchsql { SELECT * FROM t1 WHERE t1 MATCH 'a' }
} {1 {invalid fts5 file format (found 3, expected 2) - run 'rebuild'}}


do_test 1.6 {
  db close
  sqlite3 db test.db
  catchsql { INSERT INTO t1 VALUES('x y z') }
} {1 {invalid fts5 file format (found 3, expected 2) - run 'rebuild'}}

do_test 1.7 {

    }
  }
}

set dbfile [lindex $argv end-1]
if {$O(delete)} { file delete -force $dbfile }
sqlite3 db $dbfile

db func loadfile loadfile

db transaction {
  set pref ""
  if {$O(prefix)!=""} { set pref ", prefix='$O(prefix)'" }
  catch {
    db eval "CREATE VIRTUAL TABLE t1 USING $O(vtab) (path, content$O(tok)$pref)"

    }
  }
}

set dbfile [lindex $argv end-1]
if {$O(delete)} { file delete -force $dbfile }
sqlite3 db $dbfile
catch { load_static_extension db fts5 }
db func loadfile loadfile

db transaction {
  set pref ""
  if {$O(prefix)!=""} { set pref ", prefix='$O(prefix)'" }
  catch {
    db eval "CREATE VIRTUAL TABLE t1 USING $O(vtab) (path, content$O(tok)$pref)"

  %dir%/fts5_varint.c
  %dir%/fts5_vocab.c
  fts5parse.c
}]

set G(hdr) {

#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS5) 

#if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
# define NDEBUG 1
#endif
#if defined(NDEBUG) && defined(SQLITE_DEBUG)
# undef NDEBUG
#endif

}

set G(footer) {
    
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS5) */
}




proc readfile {zFile} {
  set fd [open $zFile]
  set data [read $fd]
  close $fd
  return $data
}

















proc fts5c_init {zOut} {
  global G
  set G(fd) stdout
  set G(fd) [open $zOut w]

  puts -nonewline $G(fd) $G(hdr)
}

proc fts5c_printfile {zIn} {
  global G
  set data [readfile $zIn]

  puts $G(fd) "#line 1 \"[file tail $zIn]\""






  foreach line [split $data "\n"] {
    if {[regexp {^#include.*fts5} $line]} continue
    if {[regexp {^(const )?[a-zA-Z][a-zA-Z0-9]* [*]?sqlite3Fts5} $line]} {
      set line "static $line"
    }

    puts $G(fd) $line
  }
}

proc fts5c_close {} {
  global G
  puts -nonewline $G(fd) $G(footer)

  %dir%/fts5_varint.c
  %dir%/fts5_vocab.c
  fts5parse.c
}]

set G(hdr) {

#if !defined(SQLITE_TEST) || defined(SQLITE_ENABLE_FTS5) 

#if !defined(NDEBUG) && !defined(SQLITE_DEBUG) 
# define NDEBUG 1
#endif
#if defined(NDEBUG) && defined(SQLITE_DEBUG)
# undef NDEBUG
#endif

}

set G(footer) {
    
#endif /* !defined(SQLITE_TEST) || defined(SQLITE_ENABLE_FTS5) */
}

#-------------------------------------------------------------------------
# Read and return the entire contents of text file $zFile from disk.
#
proc readfile {zFile} {
  set fd [open $zFile]
  set data [read $fd]
  close $fd
  return $data
}

#-------------------------------------------------------------------------
# This command returns a string identifying the current sqlite version -
# the equivalent of the SQLITE_SOURCE_ID string.
#
proc fts5_source_id {zDir} {
  set top [file dirname [file dirname $zDir]]
  set uuid [string trim [readfile [file join $top manifest.uuid]]]

  set L [split [readfile [file join $top manifest]]] 
  set date [lindex $L [expr [lsearch -exact $L D]+1]]
  set date [string range $date 0 [string last . $date]-1]
  set date [string map {T { }} $date]

  return "fts5: $date $uuid"
}

proc fts5c_init {zOut} {
  global G
  set G(fd) stdout
  set G(fd) [open $zOut w]

  puts -nonewline $G(fd) $G(hdr)
}

proc fts5c_printfile {zIn} {
  global G
  set data [readfile $zIn]
  set zTail [file tail $zIn]
  puts $G(fd) "#line 2 \"$zTail\""

  set sub_map [list --FTS5-SOURCE-ID-- [fts5_source_id $::srcdir]]
  if {$zTail=="fts5parse.c"} {
    lappend sub_map yy fts5yy YY fts5YY TOKEN FTS5TOKEN
  }

  foreach line [split $data "\n"] {
    if {[regexp {^#include.*fts5} $line]} continue
    if {[regexp {^(const )?[a-zA-Z][a-zA-Z0-9]* [*]?sqlite3Fts5} $line]} {
      set line "static $line"
    }
    set line [string map $sub_map $line]
    puts $G(fd) $line
  }
}

proc fts5c_close {} {
  global G
  puts -nonewline $G(fd) $G(footer)

proc usage {} {
  puts stderr "usage: $::argv0 database table"
  puts stderr ""
  exit 1
}

set o(vtab)       fts5
set o(tok)        ""
set o(limit)      0
set o(automerge)  -1
set o(crisismerge)  -1

if {[llength $argv]!=2} usage

set database [lindex $argv 0]
set tbl [lindex $argv 1]






sqlite3 db $database


db eval "SELECT fts5_decode(rowid, block) AS d FROM ${tbl}_data WHERE id=10" {
  foreach lvl [lrange $d 1 end] {
    puts $lvl



  }
}

#-------------------------------------------------------------------------
# Process command line arguments.
#
proc usage {} {
  puts stderr "usage: $::argv0 database table"
  puts stderr ""
  exit 1
}







if {[llength $argv]!=2} usage

set database [lindex $argv 0]
set tbl [lindex $argv 1]



#-------------------------------------------------------------------------
# Start of main program.
#
sqlite3 db $database
catch { load_static_extension db fts5 }

db eval "SELECT fts5_decode(rowid, block) AS d FROM ${tbl}_data WHERE id=10" {
  foreach lvl [lrange $d 1 end] {
    puts [lrange $lvl 0 2]
    foreach seg [lrange $lvl 3 end] {
      puts "        $seg"
    }
  }
}

  do_test 2.$tn.11 {
    sqlite3ota ota test.db ota.db
    while {[ota step]=="SQLITE_OK"} {}
    ota close
  } {SQLITE_DONE}

}
































































finish_test

  do_test 2.$tn.11 {
    sqlite3ota ota test.db ota.db
    while {[ota step]=="SQLITE_OK"} {}
    ota close
  } {SQLITE_DONE}

}

#-------------------------------------------------------------------------
# Test that "PRAGMA data_version" works when an OTA client writes the
# database.
#
do_multiclient_test tn {

  # Initialize a target (test.db) and ota (ota.db) database.
  #
  forcedelete ota.db
  sql1 $setup_sql

  # Check the initial database contains table "xx" with a single row.
  # Also save the current values of "PRAGMA data-version" for [db1] 
  # and [db2].
  #
  do_test 2.$tn.1 {
    list [sql1 { SELECT count(*) FROM xx }] [sql2 { SELECT count(*) FROM xx }]
  } {1 1}
  set V1 [sql1 {PRAGMA data_version}] 
  set V2 [sql2 {PRAGMA data_version}]

  # Check the values of data-version have not magically changed.
  #
  do_test 2.$tn.2 {
    list [sql1 {PRAGMA data_version}] [sql2 {PRAGMA data_version}]
  } [list $V1 $V2]

  # Start stepping the OTA. From the point of view of [db1] and [db2], the 
  # data-version values remain unchanged until the database contents are
  # modified. At which point the values are incremented.
  #
  sqlite3ota ota test.db ota.db
  set x 0
  while {[db one {SELECT count(*) FROM xx}]==1} {
    do_test 2.$tn.3.[incr x] {
      list [sql1 {PRAGMA data_version}] [sql2 {PRAGMA data_version}]
    } [list $V1 $V2]
    ota step
  }
  do_test 2.$tn.5.1 { expr {$V1 < [sql1 {PRAGMA data_version}]} } 1
  do_test 2.$tn.5.2 { expr {$V2 < [sql2 {PRAGMA data_version}]} } 1

  # Check the db contents is as expected.
  #
  do_test 2.$tn.4 {
    list [sql1 {SELECT count(*) FROM xx}] [sql2 {SELECT count(*) FROM xx}]
  } {3 3}

  set V1 [sql1 {PRAGMA data_version}] 
  set V2 [sql2 {PRAGMA data_version}]

  # Finish applying the OTA (i.e. do the incremental checkpoint). Check that
  # this does not cause the data-version values to change.
  #
  while {[ota step]=="SQLITE_OK"} { }
  ota close

  do_test 2.$tn.6 {
    list [sql1 {PRAGMA data_version}] [sql2 {PRAGMA data_version}]
  } [list $V1 $V2]

}

finish_test

	 vdbetrace.o wal.o walker.o where.o wherecode.o whereexpr.o \
         utf.o vtab.o

LIBOBJ += sqlite3session.o

LIBOBJ += fts5.o



# All of the source code files.
#
SRC = \
  $(TOP)/src/alter.c \
  $(TOP)/src/analyze.c \
  $(TOP)/src/attach.c \
  $(TOP)/src/auth.c \
................................................................................
  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/percentile.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/totype.c \
  $(TOP)/ext/misc/wholenumber.c \
  $(TOP)/ext/misc/vfslog.c \
  $(TOP)/ext/fts5/fts5_tcl.c 



#TESTSRC += $(TOP)/ext/fts2/fts2_tokenizer.c
#TESTSRC += $(TOP)/ext/fts3/fts3_tokenizer.c

TESTSRC2 = \
  $(TOP)/src/attach.c \
................................................................................
   $(TOP)/ext/fts5/fts5_varint.c \
   $(TOP)/ext/fts5/fts5_vocab.c  \

fts5parse.c:	$(TOP)/ext/fts5/fts5parse.y lemon 
	cp $(TOP)/ext/fts5/fts5parse.y .
	rm -f fts5parse.h
	./lemon $(OPTS) fts5parse.y
	mv fts5parse.c fts5parse.c.orig
	cat fts5parse.c.orig | sed 's/yy/fts5yy/g' | sed 's/YY/fts5YY/g' \
		| sed 's/TOKEN/FTS5TOKEN/g' >> fts5parse.c

fts5parse.h: fts5parse.c

fts5.c: $(FTS5_SRC)
	tclsh $(TOP)/ext/fts5/tool/mkfts5c.tcl

fts5.o:	fts5.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c fts5.c




userauth.o:	$(TOP)/ext/userauth/userauth.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/userauth/userauth.c

sqlite3session.o:	$(TOP)/ext/session/sqlite3session.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/session/sqlite3session.c
................................................................................
	rm -f shell.c sqlite3ext.h
	rm -f sqlite3_analyzer sqlite3_analyzer.exe sqlite3_analyzer.c
	rm -f sqlite-*-output.vsix
	rm -f mptester mptester.exe
	rm -f fuzzershell fuzzershell.exe
	rm -f fuzzcheck fuzzcheck.exe
	rm -f sqldiff sqldiff.exe

	 vdbetrace.o wal.o walker.o where.o wherecode.o whereexpr.o \
         utf.o vtab.o

LIBOBJ += sqlite3session.o

LIBOBJ += fts5.o



# All of the source code files.
#
SRC = \
  $(TOP)/src/alter.c \
  $(TOP)/src/analyze.c \
  $(TOP)/src/attach.c \
  $(TOP)/src/auth.c \
................................................................................
  $(TOP)/ext/misc/nextchar.c \
  $(TOP)/ext/misc/percentile.c \
  $(TOP)/ext/misc/regexp.c \
  $(TOP)/ext/misc/spellfix.c \
  $(TOP)/ext/misc/totype.c \
  $(TOP)/ext/misc/wholenumber.c \
  $(TOP)/ext/misc/vfslog.c \
  $(TOP)/ext/fts5/fts5_tcl.c \
  fts5.c


#TESTSRC += $(TOP)/ext/fts2/fts2_tokenizer.c
#TESTSRC += $(TOP)/ext/fts3/fts3_tokenizer.c

TESTSRC2 = \
  $(TOP)/src/attach.c \
................................................................................
   $(TOP)/ext/fts5/fts5_varint.c \
   $(TOP)/ext/fts5/fts5_vocab.c  \

fts5parse.c:	$(TOP)/ext/fts5/fts5parse.y lemon 
	cp $(TOP)/ext/fts5/fts5parse.y .
	rm -f fts5parse.h
	./lemon $(OPTS) fts5parse.y




fts5parse.h: fts5parse.c

fts5.c: $(FTS5_SRC)
	tclsh $(TOP)/ext/fts5/tool/mkfts5c.tcl




	cp $(TOP)/ext/fts5/fts5.h .


userauth.o:	$(TOP)/ext/userauth/userauth.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/userauth/userauth.c

sqlite3session.o:	$(TOP)/ext/session/sqlite3session.c $(HDR) $(EXTHDR)
	$(TCCX) -DSQLITE_CORE -c $(TOP)/ext/session/sqlite3session.c
................................................................................
	rm -f shell.c sqlite3ext.h
	rm -f sqlite3_analyzer sqlite3_analyzer.exe sqlite3_analyzer.c
	rm -f sqlite-*-output.vsix
	rm -f mptester mptester.exe
	rm -f fuzzershell fuzzershell.exe
	rm -f fuzzcheck fuzzcheck.exe
	rm -f sqldiff sqldiff.exe
	rm -f fts5.c fts5.h fts5parse.*

  u8 *pCell;               /* Cell content */
  u8 *pCellIdx;            /* Next element of the cell pointer array */
  BtShared *pBt;           /* The BtShared object that owns pPage */
  u32 pc;                  /* Address of a cell */
  u32 usableSize;          /* Usable size of the page */
  u32 contentOffset;       /* Offset to the start of the cell content area */
  u32 *heap = 0;           /* Min-heap used for checking cell coverage */
  u32 x, prev = 0;
  const char *saved_zPfx = pCheck->zPfx;
  int saved_v1 = pCheck->v1;
  int saved_v2 = pCheck->v2;


  /* Check that the page exists
  */
  pBt = pCheck->pBt;
  usableSize = pBt->usableSize;
  if( iPage==0 ) return 0;
  if( checkRef(pCheck, iPage) ) return 0;
................................................................................
    checkAppendMsg(pCheck,
       "unable to get the page. error code=%d", rc);
    goto end_of_check;
  }

  /* Clear MemPage.isInit to make sure the corruption detection code in
  ** btreeInitPage() is executed.  */

  pPage->isInit = 0;
  if( (rc = btreeInitPage(pPage))!=0 ){
    assert( rc==SQLITE_CORRUPT );  /* The only possible error from InitPage */
    checkAppendMsg(pCheck,
                   "btreeInitPage() returns error code %d", rc);
    goto end_of_check;
  }
................................................................................
    depth = checkTreePage(pCheck, pgno, &maxKey, maxKey);
    keyCanBeEqual = 0;
  }else{
    /* For leaf pages, the coverage check will occur in the same loop
    ** as the other cell checks, so initialize the heap.  */
    heap = pCheck->heap;
    heap[0] = 0;
    btreeHeapInsert(heap, contentOffset-1);
  }

  /* EVIDENCE-OF: R-02776-14802 The cell pointer array consists of K 2-byte
  ** integer offsets to the cell contents. */
  for(i=nCell-1; i>=0 && pCheck->mxErr; i--){
    CellInfo info;

................................................................................
  if( doCoverageCheck && pCheck->mxErr>0 ){
    /* For leaf pages, the min-heap has already been initialized and the
    ** cells have already been inserted.  But for internal pages, that has
    ** not yet been done, so do it now */
    if( !pPage->leaf ){
      heap = pCheck->heap;
      heap[0] = 0;
      btreeHeapInsert(heap, contentOffset-1);
      for(i=nCell-1; i>=0; i--){
        u32 size;
        pc = get2byteAligned(&data[cellStart+i*2]);
        size = pPage->xCellSize(pPage, &data[pc]);
        btreeHeapInsert(heap, (pc<<16)|(pc+size-1));
      }
    }
................................................................................
    */
    i = get2byte(&data[hdr+1]);
    while( i>0 ){
      int size, j;
      assert( (u32)i<=usableSize-4 );     /* Enforced by btreeInitPage() */
      size = get2byte(&data[i+2]);
      assert( (u32)(i+size)<=usableSize );  /* Enforced by btreeInitPage() */
      btreeHeapInsert(heap, (i<<16)|(i+size-1));
      /* EVIDENCE-OF: R-58208-19414 The first 2 bytes of a freeblock are a
      ** big-endian integer which is the offset in the b-tree page of the next
      ** freeblock in the chain, or zero if the freeblock is the last on the
      ** chain. */
      j = get2byte(&data[i]);
      /* EVIDENCE-OF: R-06866-39125 Freeblocks are always connected in order of
      ** increasing offset. */
      assert( j==0 || j>i+size );  /* Enforced by btreeInitPage() */
      assert( (u32)j<=usableSize-4 );   /* Enforced by btreeInitPage() */
      i = j;
    }
    /* Analyze the min-heap looking for overlap between cells and/or 
    ** freeblocks, and counting the number of untracked bytes in nFrag.










    */
    nFrag = 0;
    assert( heap[0]>0 );
    assert( (heap[1]>>16)==0 );
    btreeHeapPull(heap,&prev);

    while( btreeHeapPull(heap,&x) ){
      if( (prev&0xffff)+1>(x>>16) ){
        checkAppendMsg(pCheck,
          "Multiple uses for byte %u of page %d", x>>16, iPage);
        break;
      }else{
        nFrag += (x>>16) - (prev&0xffff) - 1;
        prev = x;
      }
................................................................................
      checkAppendMsg(pCheck,
          "Fragmentation of %d bytes reported as %d on page %d",
          nFrag, data[hdr+7], iPage);
    }
  }

end_of_check:

  releasePage(pPage);
  pCheck->zPfx = saved_zPfx;
  pCheck->v1 = saved_v1;
  pCheck->v2 = saved_v2;
  return depth+1;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

  u8 *pCell;               /* Cell content */
  u8 *pCellIdx;            /* Next element of the cell pointer array */
  BtShared *pBt;           /* The BtShared object that owns pPage */
  u32 pc;                  /* Address of a cell */
  u32 usableSize;          /* Usable size of the page */
  u32 contentOffset;       /* Offset to the start of the cell content area */
  u32 *heap = 0;           /* Min-heap used for checking cell coverage */
  u32 x, prev = 0;         /* Next and previous entry on the min-heap */
  const char *saved_zPfx = pCheck->zPfx;
  int saved_v1 = pCheck->v1;
  int saved_v2 = pCheck->v2;
  u8 savedIsInit;

  /* Check that the page exists
  */
  pBt = pCheck->pBt;
  usableSize = pBt->usableSize;
  if( iPage==0 ) return 0;
  if( checkRef(pCheck, iPage) ) return 0;
................................................................................
    checkAppendMsg(pCheck,
       "unable to get the page. error code=%d", rc);
    goto end_of_check;
  }

  /* Clear MemPage.isInit to make sure the corruption detection code in
  ** btreeInitPage() is executed.  */
  savedIsInit = pPage->isInit;
  pPage->isInit = 0;
  if( (rc = btreeInitPage(pPage))!=0 ){
    assert( rc==SQLITE_CORRUPT );  /* The only possible error from InitPage */
    checkAppendMsg(pCheck,
                   "btreeInitPage() returns error code %d", rc);
    goto end_of_check;
  }
................................................................................
    depth = checkTreePage(pCheck, pgno, &maxKey, maxKey);
    keyCanBeEqual = 0;
  }else{
    /* For leaf pages, the coverage check will occur in the same loop
    ** as the other cell checks, so initialize the heap.  */
    heap = pCheck->heap;
    heap[0] = 0;

  }

  /* EVIDENCE-OF: R-02776-14802 The cell pointer array consists of K 2-byte
  ** integer offsets to the cell contents. */
  for(i=nCell-1; i>=0 && pCheck->mxErr; i--){
    CellInfo info;

................................................................................
  if( doCoverageCheck && pCheck->mxErr>0 ){
    /* For leaf pages, the min-heap has already been initialized and the
    ** cells have already been inserted.  But for internal pages, that has
    ** not yet been done, so do it now */
    if( !pPage->leaf ){
      heap = pCheck->heap;
      heap[0] = 0;

      for(i=nCell-1; i>=0; i--){
        u32 size;
        pc = get2byteAligned(&data[cellStart+i*2]);
        size = pPage->xCellSize(pPage, &data[pc]);
        btreeHeapInsert(heap, (pc<<16)|(pc+size-1));
      }
    }
................................................................................
    */
    i = get2byte(&data[hdr+1]);
    while( i>0 ){
      int size, j;
      assert( (u32)i<=usableSize-4 );     /* Enforced by btreeInitPage() */
      size = get2byte(&data[i+2]);
      assert( (u32)(i+size)<=usableSize );  /* Enforced by btreeInitPage() */
      btreeHeapInsert(heap, (((u32)i)<<16)|(i+size-1));
      /* EVIDENCE-OF: R-58208-19414 The first 2 bytes of a freeblock are a
      ** big-endian integer which is the offset in the b-tree page of the next
      ** freeblock in the chain, or zero if the freeblock is the last on the
      ** chain. */
      j = get2byte(&data[i]);
      /* EVIDENCE-OF: R-06866-39125 Freeblocks are always connected in order of
      ** increasing offset. */
      assert( j==0 || j>i+size );  /* Enforced by btreeInitPage() */
      assert( (u32)j<=usableSize-4 );   /* Enforced by btreeInitPage() */
      i = j;
    }
    /* Analyze the min-heap looking for overlap between cells and/or 
    ** freeblocks, and counting the number of untracked bytes in nFrag.
    ** 
    ** Each min-heap entry is of the form:    (start_address<<16)|end_address.
    ** There is an implied first entry the covers the page header, the cell
    ** pointer index, and the gap between the cell pointer index and the start
    ** of cell content.  
    **
    ** The loop below pulls entries from the min-heap in order and compares
    ** the start_address against the previous end_address.  If there is an
    ** overlap, that means bytes are used multiple times.  If there is a gap,
    ** that gap is added to the fragmentation count.
    */
    nFrag = 0;



    prev = contentOffset - 1;   /* Implied first min-heap entry */
    while( btreeHeapPull(heap,&x) ){
      if( (prev&0xffff)>=(x>>16) ){
        checkAppendMsg(pCheck,
          "Multiple uses for byte %u of page %d", x>>16, iPage);
        break;
      }else{
        nFrag += (x>>16) - (prev&0xffff) - 1;
        prev = x;
      }
................................................................................
      checkAppendMsg(pCheck,
          "Fragmentation of %d bytes reported as %d on page %d",
          nFrag, data[hdr+7], iPage);
    }
  }

end_of_check:
  if( !doCoverageCheck ) pPage->isInit = savedIsInit;
  releasePage(pPage);
  pCheck->zPfx = saved_zPfx;
  pCheck->v1 = saved_v1;
  pCheck->v2 = saved_v2;
  return depth+1;
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */

   SQLITE_DEFAULT_MMAP_SIZE,  /* szMmap */
   SQLITE_MAX_MMAP_SIZE,      /* mxMmap */
   (void*)0,                  /* pScratch */
   0,                         /* szScratch */
   0,                         /* nScratch */
   (void*)0,                  /* pPage */
   0,                         /* szPage */
   0,                         /* nPage */
   0,                         /* mxParserStack */
   0,                         /* sharedCacheEnabled */
   SQLITE_SORTER_PMASZ,       /* szPma */
   /* All the rest should always be initialized to zero */
   0,                         /* isInit */
   0,                         /* inProgress */
   0,                         /* isMutexInit */

   SQLITE_DEFAULT_MMAP_SIZE,  /* szMmap */
   SQLITE_MAX_MMAP_SIZE,      /* mxMmap */
   (void*)0,                  /* pScratch */
   0,                         /* szScratch */
   0,                         /* nScratch */
   (void*)0,                  /* pPage */
   0,                         /* szPage */
   SQLITE_DEFAULT_PCACHE_INITSZ, /* nPage */
   0,                         /* mxParserStack */
   0,                         /* sharedCacheEnabled */
   SQLITE_SORTER_PMASZ,       /* szPma */
   /* All the rest should always be initialized to zero */
   0,                         /* isInit */
   0,                         /* inProgress */
   0,                         /* isMutexInit */

  }else{
    mem0.pScratchEnd = 0;
    sqlite3GlobalConfig.pScratch = 0;
    sqlite3GlobalConfig.szScratch = 0;
    sqlite3GlobalConfig.nScratch = 0;
  }
  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
      || sqlite3GlobalConfig.nPage<1 ){
    sqlite3GlobalConfig.pPage = 0;
    sqlite3GlobalConfig.szPage = 0;
    sqlite3GlobalConfig.nPage = 0;
  }
  rc = sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
  if( rc!=SQLITE_OK ) memset(&mem0, 0, sizeof(mem0));
  return rc;
}

/*

  }else{
    mem0.pScratchEnd = 0;
    sqlite3GlobalConfig.pScratch = 0;
    sqlite3GlobalConfig.szScratch = 0;
    sqlite3GlobalConfig.nScratch = 0;
  }
  if( sqlite3GlobalConfig.pPage==0 || sqlite3GlobalConfig.szPage<512
      || sqlite3GlobalConfig.nPage<=0 ){
    sqlite3GlobalConfig.pPage = 0;
    sqlite3GlobalConfig.szPage = 0;

  }
  rc = sqlite3GlobalConfig.m.xInit(sqlite3GlobalConfig.m.pAppData);
  if( rc!=SQLITE_OK ) memset(&mem0, 0, sizeof(mem0));
  return rc;
}

/*

/*
** The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it.  If it returns NULL
** that means that a mutex could not be allocated. 
*/
static sqlite3_mutex *debugMutexAlloc(int id){
  static sqlite3_debug_mutex aStatic[SQLITE_MUTEX_STATIC_APP3 - 1];
  sqlite3_debug_mutex *pNew = 0;
  switch( id ){
    case SQLITE_MUTEX_FAST:
    case SQLITE_MUTEX_RECURSIVE: {
      pNew = sqlite3Malloc(sizeof(*pNew));
      if( pNew ){
        pNew->id = id;

/*
** The sqlite3_mutex_alloc() routine allocates a new
** mutex and returns a pointer to it.  If it returns NULL
** that means that a mutex could not be allocated. 
*/
static sqlite3_mutex *debugMutexAlloc(int id){
  static sqlite3_debug_mutex aStatic[SQLITE_MUTEX_STATIC_VFS3 - 1];
  sqlite3_debug_mutex *pNew = 0;
  switch( id ){
    case SQLITE_MUTEX_FAST:
    case SQLITE_MUTEX_RECURSIVE: {
      pNew = sqlite3Malloc(sizeof(*pNew));
      if( pNew ){
        pNew->id = id;

** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** <li>  SQLITE_MUTEX_STATIC_APP3



** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
................................................................................
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
** returns a different mutex on every call.  But for the static 
** mutex types, the same mutex is returned on every call that has
** the same type number.
*/
static sqlite3_mutex *pthreadMutexAlloc(int iType){
  static sqlite3_mutex staticMutexes[] = {



    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,

** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** <li>  SQLITE_MUTEX_STATIC_APP3
** <li>  SQLITE_MUTEX_STATIC_VFS1
** <li>  SQLITE_MUTEX_STATIC_VFS2
** <li>  SQLITE_MUTEX_STATIC_VFS3
** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does
................................................................................
** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()
** returns a different mutex on every call.  But for the static 
** mutex types, the same mutex is returned on every call that has
** the same type number.
*/
static sqlite3_mutex *pthreadMutexAlloc(int iType){
  static sqlite3_mutex staticMutexes[] = {
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,
    SQLITE3_MUTEX_INITIALIZER,

  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,



  SQLITE3_MUTEX_INITIALIZER
};

static int winMutex_isInit = 0;
static int winMutex_isNt = -1; /* <0 means "need to query" */

/* As the winMutexInit() and winMutexEnd() functions are called as part
................................................................................
** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** <li>  SQLITE_MUTEX_STATIC_APP3



** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does

  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER,
  SQLITE3_MUTEX_INITIALIZER
};

static int winMutex_isInit = 0;
static int winMutex_isNt = -1; /* <0 means "need to query" */

/* As the winMutexInit() and winMutexEnd() functions are called as part
................................................................................
** <li>  SQLITE_MUTEX_STATIC_OPEN
** <li>  SQLITE_MUTEX_STATIC_PRNG
** <li>  SQLITE_MUTEX_STATIC_LRU
** <li>  SQLITE_MUTEX_STATIC_PMEM
** <li>  SQLITE_MUTEX_STATIC_APP1
** <li>  SQLITE_MUTEX_STATIC_APP2
** <li>  SQLITE_MUTEX_STATIC_APP3
** <li>  SQLITE_MUTEX_STATIC_VFS1
** <li>  SQLITE_MUTEX_STATIC_VFS2
** <li>  SQLITE_MUTEX_STATIC_VFS3
** </ul>
**
** The first two constants cause sqlite3_mutex_alloc() to create
** a new mutex.  The new mutex is recursive when SQLITE_MUTEX_RECURSIVE
** is used but not necessarily so when SQLITE_MUTEX_FAST is used.
** The mutex implementation does not need to make a distinction
** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does

** statements. e.g.
**
**   unixEnterMutex()
**     assert( unixMutexHeld() );
**   unixEnterLeave()
*/
static void unixEnterMutex(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
static void unixLeaveMutex(void){
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
#ifdef SQLITE_DEBUG
static int unixMutexHeld(void) {
  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
#endif


#ifdef SQLITE_HAVE_OS_TRACE
/*
** Helper function for printing out trace information from debugging

** statements. e.g.
**
**   unixEnterMutex()
**     assert( unixMutexHeld() );
**   unixEnterLeave()
*/
static void unixEnterMutex(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
}
static void unixLeaveMutex(void){
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
}
#ifdef SQLITE_DEBUG
static int unixMutexHeld(void) {
  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
}
#endif


#ifdef SQLITE_HAVE_OS_TRACE
/*
** Helper function for printing out trace information from debugging

** statements. e.g.
**
**   winShmEnterMutex()
**     assert( winShmMutexHeld() );
**   winShmLeaveMutex()
*/
static void winShmEnterMutex(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
static void winShmLeaveMutex(void){
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
#ifndef NDEBUG
static int winShmMutexHeld(void) {
  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
}
#endif

/*
** Object used to represent a single file opened and mmapped to provide
** shared memory.  When multiple threads all reference the same
** log-summary, each thread has its own winFile object, but they all

** statements. e.g.
**
**   winShmEnterMutex()
**     assert( winShmMutexHeld() );
**   winShmLeaveMutex()
*/
static void winShmEnterMutex(void){
  sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
}
static void winShmLeaveMutex(void){
  sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
}
#ifndef NDEBUG
static int winShmMutexHeld(void) {
  return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_VFS1));
}
#endif

/*
** Object used to represent a single file opened and mmapped to provide
** shared memory.  When multiple threads all reference the same
** log-summary, each thread has its own winFile object, but they all

*************************************************************************
**
** This file implements the default page cache implementation (the
** sqlite3_pcache interface). It also contains part of the implementation
** of the SQLITE_CONFIG_PAGECACHE and sqlite3_release_memory() features.
** If the default page cache implementation is overridden, then neither of
** these two features are available.
































































*/

#include "sqliteInt.h"

typedef struct PCache1 PCache1;
typedef struct PgHdr1 PgHdr1;
typedef struct PgFreeslot PgFreeslot;
typedef struct PGroup PGroup;

................................................................................
struct PCache1 {
  /* Cache configuration parameters. Page size (szPage) and the purgeable
  ** flag (bPurgeable) are set when the cache is created. nMax may be 
  ** modified at any time by a call to the pcache1Cachesize() method.
  ** The PGroup mutex must be held when accessing nMax.
  */
  PGroup *pGroup;                     /* PGroup this cache belongs to */
  int szPage;                         /* Size of allocated pages in bytes */
  int szExtra;                        /* Size of extra space in bytes */

  int bPurgeable;                     /* True if cache is purgeable */
  unsigned int nMin;                  /* Minimum number of pages reserved */
  unsigned int nMax;                  /* Configured "cache_size" value */
  unsigned int n90pct;                /* nMax*9/10 */
  unsigned int iMaxKey;               /* Largest key seen since xTruncate() */

  /* Hash table of all pages. The following variables may only be accessed
  ** when the accessor is holding the PGroup mutex.
  */
  unsigned int nRecyclable;           /* Number of pages in the LRU list */
  unsigned int nPage;                 /* Total number of pages in apHash */
  unsigned int nHash;                 /* Number of slots in apHash[] */
  PgHdr1 **apHash;                    /* Hash table for fast lookup by key */


};

/*
** Each cache entry is represented by an instance of the following 
** structure. Unless SQLITE_PCACHE_SEPARATE_HEADER is defined, a buffer of
** PgHdr1.pCache->szPage bytes is allocated directly before this structure 
** in memory.
*/
struct PgHdr1 {
  sqlite3_pcache_page page;
  unsigned int iKey;             /* Key value (page number) */
  u8 isPinned;                   /* Page in use, not on the LRU list */

  PgHdr1 *pNext;                 /* Next in hash table chain */
  PCache1 *pCache;               /* Cache that currently owns this page */
  PgHdr1 *pLruNext;              /* Next in LRU list of unpinned pages */
  PgHdr1 *pLruPrev;              /* Previous in LRU list of unpinned pages */
};

/*
** Free slots in the allocator used to divide up the buffer provided using
** the SQLITE_CONFIG_PAGECACHE mechanism.
*/
struct PgFreeslot {
  PgFreeslot *pNext;  /* Next free slot */
};

/*
** Global data used by this cache.
................................................................................

  /* Variables related to SQLITE_CONFIG_PAGECACHE settings.  The
  ** szSlot, nSlot, pStart, pEnd, nReserve, and isInit values are all
  ** fixed at sqlite3_initialize() time and do not require mutex protection.
  ** The nFreeSlot and pFree values do require mutex protection.
  */
  int isInit;                    /* True if initialized */

  int szSlot;                    /* Size of each free slot */
  int nSlot;                     /* The number of pcache slots */
  int nReserve;                  /* Try to keep nFreeSlot above this */
  void *pStart, *pEnd;           /* Bounds of pagecache malloc range */
  /* Above requires no mutex.  Use mutex below for variable that follow. */
  sqlite3_mutex *mutex;          /* Mutex for accessing the following: */
  PgFreeslot *pFree;             /* Free page blocks */
  int nFreeSlot;                 /* Number of unused pcache slots */
  /* The following value requires a mutex to change.  We skip the mutex on
  ** reading because (1) most platforms read a 32-bit integer atomically and
  ** (2) even if an incorrect value is read, no great harm is done since this
................................................................................
**
** This routine is called from sqlite3_initialize() and so it is guaranteed
** to be serialized already.  There is no need for further mutexing.
*/
void sqlite3PCacheBufferSetup(void *pBuf, int sz, int n){
  if( pcache1.isInit ){
    PgFreeslot *p;

    sz = ROUNDDOWN8(sz);
    pcache1.szSlot = sz;
    pcache1.nSlot = pcache1.nFreeSlot = n;
    pcache1.nReserve = n>90 ? 10 : (n/10 + 1);
    pcache1.pStart = pBuf;
    pcache1.pFree = 0;
    pcache1.bUnderPressure = 0;
................................................................................
  }
  return p;
}

/*
** Free an allocated buffer obtained from pcache1Alloc().
*/
static int pcache1Free(void *p){
  int nFreed = 0;
  if( p==0 ) return 0;
  if( p>=pcache1.pStart && p<pcache1.pEnd ){
    PgFreeslot *pSlot;
    sqlite3_mutex_enter(pcache1.mutex);
    sqlite3StatusDown(SQLITE_STATUS_PAGECACHE_USED, 1);
    pSlot = (PgFreeslot*)p;
    pSlot->pNext = pcache1.pFree;
    pcache1.pFree = pSlot;
................................................................................
    pcache1.nFreeSlot++;
    pcache1.bUnderPressure = pcache1.nFreeSlot<pcache1.nReserve;
    assert( pcache1.nFreeSlot<=pcache1.nSlot );
    sqlite3_mutex_leave(pcache1.mutex);
  }else{
    assert( sqlite3MemdebugHasType(p, MEMTYPE_PCACHE) );
    sqlite3MemdebugSetType(p, MEMTYPE_HEAP);
    nFreed = sqlite3MallocSize(p);
#ifndef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS

    sqlite3_mutex_enter(pcache1.mutex);
    sqlite3StatusDown(SQLITE_STATUS_PAGECACHE_OVERFLOW, nFreed);
    sqlite3_mutex_leave(pcache1.mutex);
#endif
    sqlite3_free(p);
  }
  return nFreed;
}

#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
/*
** Return the size of a pcache allocation
*/
static int pcache1MemSize(void *p){
................................................................................
/*
** Allocate a new page object initially associated with cache pCache.
*/
static PgHdr1 *pcache1AllocPage(PCache1 *pCache){
  PgHdr1 *p = 0;
  void *pPg;








  /* The group mutex must be released before pcache1Alloc() is called. This
  ** is because it may call sqlite3_release_memory(), which assumes that 
  ** this mutex is not held. */
  assert( sqlite3_mutex_held(pCache->pGroup->mutex) );


  pcache1LeaveMutex(pCache->pGroup);

#ifdef SQLITE_PCACHE_SEPARATE_HEADER
  pPg = pcache1Alloc(pCache->szPage);
  p = sqlite3Malloc(sizeof(PgHdr1) + pCache->szExtra);
  if( !pPg || !p ){
    pcache1Free(pPg);
    sqlite3_free(p);
    pPg = 0;
  }
#else
  pPg = pcache1Alloc(ROUND8(sizeof(PgHdr1)) + pCache->szPage + pCache->szExtra);

  p = (PgHdr1 *)&((u8 *)pPg)[pCache->szPage];
#endif

  pcache1EnterMutex(pCache->pGroup);


  if( pPg ){
    p->page.pBuf = pPg;
    p->page.pExtra = &p[1];


    if( pCache->bPurgeable ){
      pCache->pGroup->nCurrentPage++;
    }
    return p;
  }
  return 0;
}

/*
** Free a page object allocated by pcache1AllocPage().
**
** The pointer is allowed to be NULL, which is prudent.  But it turns out
** that the current implementation happens to never call this routine
** with a NULL pointer, so we mark the NULL test with ALWAYS().
*/
static void pcache1FreePage(PgHdr1 *p){
  if( ALWAYS(p) ){


    PCache1 *pCache = p->pCache;
    assert( sqlite3_mutex_held(p->pCache->pGroup->mutex) );




    pcache1Free(p->page.pBuf);
#ifdef SQLITE_PCACHE_SEPARATE_HEADER
    sqlite3_free(p);
#endif

    if( pCache->bPurgeable ){
      pCache->pGroup->nCurrentPage--;
    }
  }
}

/*
** Malloc function used by SQLite to obtain space from the buffer configured
** using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no such buffer
** exists, this function falls back to sqlite3Malloc().
................................................................................
/*
** Implementation of the sqlite3_pcache.xInit method.
*/
static int pcache1Init(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  assert( pcache1.isInit==0 );
  memset(&pcache1, 0, sizeof(pcache1));

























#if SQLITE_THREADSAFE
  if( sqlite3GlobalConfig.bCoreMutex ){
    pcache1.grp.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU);
    pcache1.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_PMEM);
  }
#endif
  pcache1.grp.mxPinned = 10;
................................................................................
** Allocate a new cache.
*/
static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
  PCache1 *pCache;      /* The newly created page cache */
  PGroup *pGroup;       /* The group the new page cache will belong to */
  int sz;               /* Bytes of memory required to allocate the new cache */

  /*
  ** The separateCache variable is true if each PCache has its own private
  ** PGroup.  In other words, separateCache is true for mode (1) where no
  ** mutexing is required.
  **
  **   *  Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
  **
  **   *  Always use a unified cache in single-threaded applications
  **
  **   *  Otherwise (if multi-threaded and ENABLE_MEMORY_MANAGEMENT is off)
  **      use separate caches (mode-1)
  */
#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT) || SQLITE_THREADSAFE==0
  const int separateCache = 0;
#else
  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;
    pCache->szPage = szPage;
    pCache->szExtra = szExtra;

    pCache->bPurgeable = (bPurgeable ? 1 : 0);
    pcache1EnterMutex(pGroup);
    pcache1ResizeHash(pCache);
    if( bPurgeable ){
      pCache->nMin = 10;
      pGroup->nMinPage += pCache->nMin;
      pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
    }
    pcache1LeaveMutex(pGroup);






























    if( pCache->nHash==0 ){
      pcache1Destroy((sqlite3_pcache*)pCache);
      pCache = 0;
    }
  }
  return (sqlite3_pcache *)pCache;
}
................................................................................
    return 0;
  }

  if( pCache->nPage>=pCache->nHash ) pcache1ResizeHash(pCache);
  assert( pCache->nHash>0 && pCache->apHash );

  /* Step 4. Try to recycle a page. */
  if( pCache->bPurgeable && pGroup->pLruTail && (
         (pCache->nPage+1>=pCache->nMax)
      || pGroup->nCurrentPage>=pGroup->nMaxPage
      || pcache1UnderMemoryPressure(pCache)
  )){
    PCache1 *pOther;
    pPage = pGroup->pLruTail;
    assert( pPage->isPinned==0 );
    pcache1RemoveFromHash(pPage, 0);
    pcache1PinPage(pPage);
    pOther = pPage->pCache;

    /* We want to verify that szPage and szExtra are the same for pOther
    ** and pCache.  Assert that we can verify this by comparing sums. */
    assert( (pCache->szPage & (pCache->szPage-1))==0 && pCache->szPage>=512 );
    assert( pCache->szExtra<512 );
    assert( (pOther->szPage & (pOther->szPage-1))==0 && pOther->szPage>=512 );
    assert( pOther->szExtra<512 );

    if( pOther->szPage+pOther->szExtra != pCache->szPage+pCache->szExtra ){

      pcache1FreePage(pPage);
      pPage = 0;
    }else{
      pGroup->nCurrentPage -= (pOther->bPurgeable - pCache->bPurgeable);
    }
  }

................................................................................
  assert( pGroup->nMaxPage >= pCache->nMax );
  pGroup->nMaxPage -= pCache->nMax;
  assert( pGroup->nMinPage >= pCache->nMin );
  pGroup->nMinPage -= pCache->nMin;
  pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
  pcache1EnforceMaxPage(pGroup);
  pcache1LeaveMutex(pGroup);

  sqlite3_free(pCache->apHash);
  sqlite3_free(pCache);
}

/*
** This function is called during initialization (sqlite3_initialize()) to
** install the default pluggable cache module, assuming the user has not
................................................................................
** been released, the function returns. The return value is the total number 
** of bytes of memory released.
*/
int sqlite3PcacheReleaseMemory(int nReq){
  int nFree = 0;
  assert( sqlite3_mutex_notheld(pcache1.grp.mutex) );
  assert( sqlite3_mutex_notheld(pcache1.mutex) );
  if( pcache1.pStart==0 ){
    PgHdr1 *p;
    pcache1EnterMutex(&pcache1.grp);
    while( (nReq<0 || nFree<nReq) && ((p=pcache1.grp.pLruTail)!=0) ){
      nFree += pcache1MemSize(p->page.pBuf);
#ifdef SQLITE_PCACHE_SEPARATE_HEADER
      nFree += sqlite3MemSize(p);
#endif

*************************************************************************
**
** This file implements the default page cache implementation (the
** sqlite3_pcache interface). It also contains part of the implementation
** of the SQLITE_CONFIG_PAGECACHE and sqlite3_release_memory() features.
** If the default page cache implementation is overridden, then neither of
** these two features are available.
**
** A Page cache line looks like this:
**
**  -------------------------------------------------------------
**  |  database page content   |  PgHdr1  |  MemPage  |  PgHdr  |
**  -------------------------------------------------------------
**
** The database page content is up front (so that buffer overreads tend to
** flow harmlessly into the PgHdr1, MemPage, and PgHdr extensions).   MemPage
** is the extension added by the btree.c module containing information such
** as the database page number and how that database page is used.  PgHdr
** is added by the pcache.c layer and contains information used to keep track
** of which pages are "dirty".  PgHdr1 is an extension added by this
** module (pcache1.c).  The PgHdr1 header is a subclass of sqlite3_pcache_page.
** PgHdr1 contains information needed to look up a page by its page number.
** The superclass sqlite3_pcache_page.pBuf points to the start of the
** database page content and sqlite3_pcache_page.pExtra points to PgHdr.
**
** The size of the extension (MemPage+PgHdr+PgHdr1) can be determined at
** runtime using sqlite3_config(SQLITE_CONFIG_PCACHE_HDRSZ, &size).  The
** sizes of the extensions sum to 272 bytes on x64 for 3.8.10, but this
** size can vary according to architecture, compile-time options, and
** SQLite library version number.
**
** If SQLITE_PCACHE_SEPARATE_HEADER is defined, then the extension is obtained
** using a separate memory allocation from the database page content.  This
** seeks to overcome the "clownshoe" problem (also called "internal
** fragmentation" in academic literature) of allocating a few bytes more
** than a power of two with the memory allocator rounding up to the next
** power of two, and leaving the rounded-up space unused.
**
** This module tracks pointers to PgHdr1 objects.  Only pcache.c communicates
** with this module.  Information is passed back and forth as PgHdr1 pointers.
**
** The pcache.c and pager.c modules deal pointers to PgHdr objects.
** The btree.c module deals with pointers to MemPage objects.
**
** SOURCE OF PAGE CACHE MEMORY:
**
** Memory for a page might come from any of three sources:
**
**    (1)  The general-purpose memory allocator - sqlite3Malloc()
**    (2)  Global page-cache memory provided using sqlite3_config() with
**         SQLITE_CONFIG_PAGECACHE.
**    (3)  PCache-local bulk allocation.
**
** The third case is a chunk of heap memory (defaulting to 100 pages worth)
** that is allocated when the page cache is created.  The size of the local
** bulk allocation can be adjusted using 
**
**     sqlite3_config(SQLITE_CONFIG_PCACHE, 0, 0, N).
**
** If N is positive, then N pages worth of memory are allocated using a single
** sqlite3Malloc() call and that memory is used for the first N pages allocated.
** Or if N is negative, then -1024*N bytes of memory are allocated and used
** for as many pages as can be accomodated.
**
** Only one of (2) or (3) can be used.  Once the memory available to (2) or
** (3) is exhausted, subsequent allocations fail over to the general-purpose
** memory allocator (1).
**
** Earlier versions of SQLite used only methods (1) and (2).  But experiments
** show that method (3) with N==100 provides about a 5% performance boost for
** common workloads.
*/

#include "sqliteInt.h"

typedef struct PCache1 PCache1;
typedef struct PgHdr1 PgHdr1;
typedef struct PgFreeslot PgFreeslot;
typedef struct PGroup PGroup;

................................................................................
struct PCache1 {
  /* Cache configuration parameters. Page size (szPage) and the purgeable
  ** flag (bPurgeable) are set when the cache is created. nMax may be 
  ** modified at any time by a call to the pcache1Cachesize() method.
  ** The PGroup mutex must be held when accessing nMax.
  */
  PGroup *pGroup;                     /* PGroup this cache belongs to */
  int szPage;                         /* Size of database content section */
  int szExtra;                        /* sizeof(MemPage)+sizeof(PgHdr) */
  int szAlloc;                        /* Total size of one pcache line */
  int bPurgeable;                     /* True if cache is purgeable */
  unsigned int nMin;                  /* Minimum number of pages reserved */
  unsigned int nMax;                  /* Configured "cache_size" value */
  unsigned int n90pct;                /* nMax*9/10 */
  unsigned int iMaxKey;               /* Largest key seen since xTruncate() */

  /* Hash table of all pages. The following variables may only be accessed
  ** when the accessor is holding the PGroup mutex.
  */
  unsigned int nRecyclable;           /* Number of pages in the LRU list */
  unsigned int nPage;                 /* Total number of pages in apHash */
  unsigned int nHash;                 /* Number of slots in apHash[] */
  PgHdr1 **apHash;                    /* Hash table for fast lookup by key */
  PgHdr1 *pFree;                      /* List of unused pcache-local pages */
  void *pBulk;                        /* Bulk memory used by pcache-local */
};

/*
** Each cache entry is represented by an instance of the following 
** structure. Unless SQLITE_PCACHE_SEPARATE_HEADER is defined, a buffer of
** PgHdr1.pCache->szPage bytes is allocated directly before this structure 
** in memory.
*/
struct PgHdr1 {
  sqlite3_pcache_page page;
  unsigned int iKey;             /* Key value (page number) */
  u8 isPinned;                   /* Page in use, not on the LRU list */
  u8 isBulkLocal;                /* This page from bulk local storage */
  PgHdr1 *pNext;                 /* Next in hash table chain */
  PCache1 *pCache;               /* Cache that currently owns this page */
  PgHdr1 *pLruNext;              /* Next in LRU list of unpinned pages */
  PgHdr1 *pLruPrev;              /* Previous in LRU list of unpinned pages */
};

/*
** Free slots in the allocator used to divide up the global page cache
** buffer provided using the SQLITE_CONFIG_PAGECACHE mechanism.
*/
struct PgFreeslot {
  PgFreeslot *pNext;  /* Next free slot */
};

/*
** Global data used by this cache.
................................................................................

  /* Variables related to SQLITE_CONFIG_PAGECACHE settings.  The
  ** szSlot, nSlot, pStart, pEnd, nReserve, and isInit values are all
  ** fixed at sqlite3_initialize() time and do not require mutex protection.
  ** The nFreeSlot and pFree values do require mutex protection.
  */
  int isInit;                    /* True if initialized */
  int separateCache;             /* Use a new PGroup for each PCache */
  int szSlot;                    /* Size of each free slot */
  int nSlot;                     /* The number of pcache slots */
  int nReserve;                  /* Try to keep nFreeSlot above this */
  void *pStart, *pEnd;           /* Bounds of global page cache memory */
  /* Above requires no mutex.  Use mutex below for variable that follow. */
  sqlite3_mutex *mutex;          /* Mutex for accessing the following: */
  PgFreeslot *pFree;             /* Free page blocks */
  int nFreeSlot;                 /* Number of unused pcache slots */
  /* The following value requires a mutex to change.  We skip the mutex on
  ** reading because (1) most platforms read a 32-bit integer atomically and
  ** (2) even if an incorrect value is read, no great harm is done since this
................................................................................
**
** This routine is called from sqlite3_initialize() and so it is guaranteed
** to be serialized already.  There is no need for further mutexing.
*/
void sqlite3PCacheBufferSetup(void *pBuf, int sz, int n){
  if( pcache1.isInit ){
    PgFreeslot *p;
    if( pBuf==0 ) sz = n = 0;
    sz = ROUNDDOWN8(sz);
    pcache1.szSlot = sz;
    pcache1.nSlot = pcache1.nFreeSlot = n;
    pcache1.nReserve = n>90 ? 10 : (n/10 + 1);
    pcache1.pStart = pBuf;
    pcache1.pFree = 0;
    pcache1.bUnderPressure = 0;
................................................................................
  }
  return p;
}

/*
** Free an allocated buffer obtained from pcache1Alloc().
*/
static void pcache1Free(void *p){
  int nFreed = 0;
  if( p==0 ) return;
  if( p>=pcache1.pStart && p<pcache1.pEnd ){
    PgFreeslot *pSlot;
    sqlite3_mutex_enter(pcache1.mutex);
    sqlite3StatusDown(SQLITE_STATUS_PAGECACHE_USED, 1);
    pSlot = (PgFreeslot*)p;
    pSlot->pNext = pcache1.pFree;
    pcache1.pFree = pSlot;
................................................................................
    pcache1.nFreeSlot++;
    pcache1.bUnderPressure = pcache1.nFreeSlot<pcache1.nReserve;
    assert( pcache1.nFreeSlot<=pcache1.nSlot );
    sqlite3_mutex_leave(pcache1.mutex);
  }else{
    assert( sqlite3MemdebugHasType(p, MEMTYPE_PCACHE) );
    sqlite3MemdebugSetType(p, MEMTYPE_HEAP);

#ifndef SQLITE_DISABLE_PAGECACHE_OVERFLOW_STATS
    nFreed = sqlite3MallocSize(p);
    sqlite3_mutex_enter(pcache1.mutex);
    sqlite3StatusDown(SQLITE_STATUS_PAGECACHE_OVERFLOW, nFreed);
    sqlite3_mutex_leave(pcache1.mutex);
#endif
    sqlite3_free(p);
  }

}

#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
/*
** Return the size of a pcache allocation
*/
static int pcache1MemSize(void *p){
................................................................................
/*
** Allocate a new page object initially associated with cache pCache.
*/
static PgHdr1 *pcache1AllocPage(PCache1 *pCache){
  PgHdr1 *p = 0;
  void *pPg;

  assert( sqlite3_mutex_held(pCache->pGroup->mutex) );
  if( pCache->pFree ){
    p = pCache->pFree;
    pCache->pFree = p->pNext;
    p->pNext = 0;
  }else{
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
    /* The group mutex must be released before pcache1Alloc() is called. This
    ** is because it might call sqlite3_release_memory(), which assumes that 
    ** this mutex is not held. */

    assert( pcache1.separateCache==0 );
    assert( pCache->pGroup==&pcache1.grp );
    pcache1LeaveMutex(pCache->pGroup);
#endif
#ifdef SQLITE_PCACHE_SEPARATE_HEADER
    pPg = pcache1Alloc(pCache->szPage);
    p = sqlite3Malloc(sizeof(PgHdr1) + pCache->szExtra);
    if( !pPg || !p ){
      pcache1Free(pPg);
      sqlite3_free(p);
      pPg = 0;
    }
#else

    pPg = pcache1Alloc(pCache->szAlloc);
    p = (PgHdr1 *)&((u8 *)pPg)[pCache->szPage];
#endif
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
    pcache1EnterMutex(pCache->pGroup);

#endif
    if( pPg==0 ) return 0;
    p->page.pBuf = pPg;
    p->page.pExtra = &p[1];
    p->isBulkLocal = 0;
  }
  if( pCache->bPurgeable ){
    pCache->pGroup->nCurrentPage++;
  }
  return p;


}

/*
** Free a page object allocated by pcache1AllocPage().




*/
static void pcache1FreePage(PgHdr1 *p){

  PCache1 *pCache;
  assert( p!=0 );
  pCache = p->pCache;
  assert( sqlite3_mutex_held(p->pCache->pGroup->mutex) );
  if( p->isBulkLocal ){
    p->pNext = pCache->pFree;
    pCache->pFree = p;
  }else{
    pcache1Free(p->page.pBuf);
#ifdef SQLITE_PCACHE_SEPARATE_HEADER
    sqlite3_free(p);
#endif
  }
  if( pCache->bPurgeable ){
    pCache->pGroup->nCurrentPage--;

  }
}

/*
** Malloc function used by SQLite to obtain space from the buffer configured
** using sqlite3_config(SQLITE_CONFIG_PAGECACHE) option. If no such buffer
** exists, this function falls back to sqlite3Malloc().
................................................................................
/*
** Implementation of the sqlite3_pcache.xInit method.
*/
static int pcache1Init(void *NotUsed){
  UNUSED_PARAMETER(NotUsed);
  assert( pcache1.isInit==0 );
  memset(&pcache1, 0, sizeof(pcache1));


  /*
  ** The pcache1.separateCache variable is true if each PCache has its own
  ** private PGroup (mode-1).  pcache1.separateCache is false if the single
  ** PGroup in pcache1.grp is used for all page caches (mode-2).
  **
  **   *  Always use a unified cache (mode-2) if ENABLE_MEMORY_MANAGEMENT
  **
  **   *  Use a unified cache in single-threaded applications that have
  **      configured a start-time buffer for use as page-cache memory using
  **      sqlite3_config(SQLITE_CONFIG_PAGECACHE, pBuf, sz, N) with non-NULL 
  **      pBuf argument.
  **
  **   *  Otherwise use separate caches (mode-1)
  */
#if defined(SQLITE_ENABLE_MEMORY_MANAGEMENT)
  pcache1.separateCache = 0;
#elif SQLITE_THREADSAFE
  pcache1.separateCache = sqlite3GlobalConfig.pPage==0
                          || sqlite3GlobalConfig.bCoreMutex>0;
#else
  pcache1.separateCache = sqlite3GlobalConfig.pPage==0;
#endif

#if SQLITE_THREADSAFE
  if( sqlite3GlobalConfig.bCoreMutex ){
    pcache1.grp.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_LRU);
    pcache1.mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_PMEM);
  }
#endif
  pcache1.grp.mxPinned = 10;
................................................................................
** Allocate a new cache.
*/
static sqlite3_pcache *pcache1Create(int szPage, int szExtra, int bPurgeable){
  PCache1 *pCache;      /* The newly created page cache */
  PGroup *pGroup;       /* The group the new page cache will belong to */
  int sz;               /* Bytes of memory required to allocate the new cache */



















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

  sz = sizeof(PCache1) + sizeof(PGroup)*pcache1.separateCache;
  pCache = (PCache1 *)sqlite3MallocZero(sz);
  if( pCache ){
    if( pcache1.separateCache ){
      pGroup = (PGroup*)&pCache[1];
      pGroup->mxPinned = 10;
    }else{
      pGroup = &pcache1.grp;
    }
    pCache->pGroup = pGroup;
    pCache->szPage = szPage;
    pCache->szExtra = szExtra;
    pCache->szAlloc = szPage + szExtra + ROUND8(sizeof(PgHdr1));
    pCache->bPurgeable = (bPurgeable ? 1 : 0);
    pcache1EnterMutex(pGroup);
    pcache1ResizeHash(pCache);
    if( bPurgeable ){
      pCache->nMin = 10;
      pGroup->nMinPage += pCache->nMin;
      pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
    }
    pcache1LeaveMutex(pGroup);
    /* Try to initialize the local bulk pagecache line allocation if using
    ** separate caches and if nPage!=0 */
    if( pcache1.separateCache
     && sqlite3GlobalConfig.nPage!=0
     && sqlite3GlobalConfig.pPage==0
    ){
      int szBulk;
      char *zBulk;
      sqlite3BeginBenignMalloc();
      if( sqlite3GlobalConfig.nPage>0 ){
        szBulk = pCache->szAlloc * sqlite3GlobalConfig.nPage;
      }else{
        szBulk = -1024*sqlite3GlobalConfig.nPage;
      }
      zBulk = pCache->pBulk = sqlite3Malloc( szBulk );
      sqlite3EndBenignMalloc();
      if( zBulk ){
        int nBulk = sqlite3MallocSize(zBulk)/pCache->szAlloc;
        int i;
        for(i=0; i<nBulk; i++){
          PgHdr1 *pX = (PgHdr1*)&zBulk[szPage];
          pX->page.pBuf = zBulk;
          pX->page.pExtra = &pX[1];
          pX->isBulkLocal = 1;
          pX->pNext = pCache->pFree;
          pCache->pFree = pX;
          zBulk += pCache->szAlloc;
        }
      }
    }
    if( pCache->nHash==0 ){
      pcache1Destroy((sqlite3_pcache*)pCache);
      pCache = 0;
    }
  }
  return (sqlite3_pcache *)pCache;
}
................................................................................
    return 0;
  }

  if( pCache->nPage>=pCache->nHash ) pcache1ResizeHash(pCache);
  assert( pCache->nHash>0 && pCache->apHash );

  /* Step 4. Try to recycle a page. */
  if( pCache->bPurgeable
   && pGroup->pLruTail

   && ((pCache->nPage+1>=pCache->nMax) || pcache1UnderMemoryPressure(pCache))
  ){
    PCache1 *pOther;
    pPage = pGroup->pLruTail;
    assert( pPage->isPinned==0 );
    pcache1RemoveFromHash(pPage, 0);
    pcache1PinPage(pPage);
    pOther = pPage->pCache;









    if( pOther->szAlloc != pCache->szAlloc ){
      pcache1FreePage(pPage);
      pPage = 0;
    }else{
      pGroup->nCurrentPage -= (pOther->bPurgeable - pCache->bPurgeable);
    }
  }

................................................................................
  assert( pGroup->nMaxPage >= pCache->nMax );
  pGroup->nMaxPage -= pCache->nMax;
  assert( pGroup->nMinPage >= pCache->nMin );
  pGroup->nMinPage -= pCache->nMin;
  pGroup->mxPinned = pGroup->nMaxPage + 10 - pGroup->nMinPage;
  pcache1EnforceMaxPage(pGroup);
  pcache1LeaveMutex(pGroup);
  sqlite3_free(pCache->pBulk);
  sqlite3_free(pCache->apHash);
  sqlite3_free(pCache);
}

/*
** This function is called during initialization (sqlite3_initialize()) to
** install the default pluggable cache module, assuming the user has not
................................................................................
** been released, the function returns. The return value is the total number 
** of bytes of memory released.
*/
int sqlite3PcacheReleaseMemory(int nReq){
  int nFree = 0;
  assert( sqlite3_mutex_notheld(pcache1.grp.mutex) );
  assert( sqlite3_mutex_notheld(pcache1.mutex) );
  if( sqlite3GlobalConfig.nPage==0 ){
    PgHdr1 *p;
    pcache1EnterMutex(&pcache1.grp);
    while( (nReq<0 || nFree<nReq) && ((p=pcache1.grp.pLruTail)!=0) ){
      nFree += pcache1MemSize(p->page.pBuf);
#ifdef SQLITE_PCACHE_SEPARATE_HEADER
      nFree += sqlite3MemSize(p);
#endif

    VdbeCoverage(v);
  }
  sqlite3VdbeResolveLabel(v, addrCont);

  /* Execute the recursive SELECT taking the single row in Current as
  ** the value for the recursive-table. Store the results in the Queue.
  */



  p->pPrior = 0;
  sqlite3Select(pParse, p, &destQueue);
  assert( p->pPrior==0 );
  p->pPrior = pSetup;


  /* Keep running the loop until the Queue is empty */
  sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
  sqlite3VdbeResolveLabel(v, addrBreak);

end_of_recursive_query:
  sqlite3ExprListDelete(pParse->db, p->pOrderBy);

    VdbeCoverage(v);
  }
  sqlite3VdbeResolveLabel(v, addrCont);

  /* Execute the recursive SELECT taking the single row in Current as
  ** the value for the recursive-table. Store the results in the Queue.
  */
  if( p->selFlags & SF_Aggregate ){
    sqlite3ErrorMsg(pParse, "recursive aggregate queries not supported");
  }else{
    p->pPrior = 0;
    sqlite3Select(pParse, p, &destQueue);
    assert( p->pPrior==0 );
    p->pPrior = pSetup;
  }

  /* Keep running the loop until the Queue is empty */
  sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop);
  sqlite3VdbeResolveLabel(v, addrBreak);

end_of_recursive_query:
  sqlite3ExprListDelete(pParse->db, p->pOrderBy);

#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */




/*
** CAPI3REF: Retrieve the mutex for a database connection
** METHOD: sqlite3
**
** ^This interface returns a pointer the [sqlite3_mutex] object that 
** serializes access to the [database connection] given in the argument

#define SQLITE_MUTEX_STATIC_PRNG      5  /* sqlite3_random() */
#define SQLITE_MUTEX_STATIC_LRU       6  /* lru page list */
#define SQLITE_MUTEX_STATIC_LRU2      7  /* NOT USED */
#define SQLITE_MUTEX_STATIC_PMEM      7  /* sqlite3PageMalloc() */
#define SQLITE_MUTEX_STATIC_APP1      8  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP2      9  /* For use by application */
#define SQLITE_MUTEX_STATIC_APP3     10  /* For use by application */
#define SQLITE_MUTEX_STATIC_VFS1     11  /* For use by built-in VFS */
#define SQLITE_MUTEX_STATIC_VFS2     12  /* For use by extension VFS */
#define SQLITE_MUTEX_STATIC_VFS3     13  /* For use by application VFS */

/*
** CAPI3REF: Retrieve the mutex for a database connection
** METHOD: sqlite3
**
** ^This interface returns a pointer the [sqlite3_mutex] object that 
** serializes access to the [database connection] given in the argument

# define SQLITE_DEFAULT_WORKER_THREADS 0
#endif
#if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
# undef SQLITE_MAX_WORKER_THREADS
# define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
#endif












/*
** GCC does not define the offsetof() macro so we'll have to do it
** ourselves.
*/
#ifndef offsetof
#define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))

# define SQLITE_DEFAULT_WORKER_THREADS 0
#endif
#if SQLITE_DEFAULT_WORKER_THREADS>SQLITE_MAX_WORKER_THREADS
# undef SQLITE_MAX_WORKER_THREADS
# define SQLITE_MAX_WORKER_THREADS SQLITE_DEFAULT_WORKER_THREADS
#endif

/*
** The default initial allocation for the pagecache when using separate
** pagecaches for each database connection.  A positive number is the
** number of pages.  A negative number N translations means that a buffer
** of -1024*N bytes is allocated and used for as many pages as it will hold.
*/
#ifndef SQLITE_DEFAULT_PCACHE_INITSZ
# define SQLITE_DEFAULT_PCACHE_INITSZ 100
#endif


/*
** GCC does not define the offsetof() macro so we'll have to do it
** ourselves.
*/
#ifndef offsetof
#define offsetof(STRUCTURE,FIELD) ((int)((char*)&((STRUCTURE*)0)->FIELD))

#include "tcl.h"
#include "sqlite3.h"
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#include <string.h>




/* defined in main.c */
extern const char *sqlite3ErrName(int);








/* A countable mutex */
struct sqlite3_mutex {
  sqlite3_mutex *pReal;
  int eType;
};

/* State variables */
static struct test_mutex_globals {
  int isInstalled;              /* True if installed */
  int disableInit;              /* True to cause sqlite3_initalize() to fail */
  int disableTry;               /* True to force sqlite3_mutex_try() to fail */
  int isInit;                   /* True if initialized */
  sqlite3_mutex_methods m;      /* Interface to "real" mutex system */
  int aCounter[8];              /* Number of grabs of each type of mutex */
  sqlite3_mutex aStatic[6];     /* The six static mutexes */
} g = {0};

/* Return true if the countable mutex is currently held */
static int counterMutexHeld(sqlite3_mutex *p){
  return g.m.xMutexHeld(p->pReal);
}

................................................................................
** Allocate a countable mutex
*/
static sqlite3_mutex *counterMutexAlloc(int eType){
  sqlite3_mutex *pReal;
  sqlite3_mutex *pRet = 0;

  assert( g.isInit );
  assert(eType<8 && eType>=0);


  pReal = g.m.xMutexAlloc(eType);
  if( !pReal ) return 0;

  if( eType==SQLITE_MUTEX_FAST || eType==SQLITE_MUTEX_RECURSIVE ){
    pRet = (sqlite3_mutex *)malloc(sizeof(sqlite3_mutex));
  }else{



    pRet = &g.aStatic[eType-2];
  }

  pRet->eType = eType;
  pRet->pReal = pReal;
  return pRet;
}

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

/*
** Enter a countable mutex.  Block until entry is safe.
*/
static void counterMutexEnter(sqlite3_mutex *p){
  assert( g.isInit );


  g.aCounter[p->eType]++;
  g.m.xMutexEnter(p->pReal);
}

/*
** Try to enter a mutex.  Return true on success.
*/
static int counterMutexTry(sqlite3_mutex *p){
  assert( g.isInit );


  g.aCounter[p->eType]++;
  if( g.disableTry ) return SQLITE_BUSY;
  return g.m.xMutexTry(p->pReal);
}

/* Leave a mutex
*/
................................................................................
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  Tcl_Obj *pRet;
  int ii;
  char *aName[8] = {
    "fast",        "recursive",   "static_master", "static_mem", 
    "static_open", "static_prng", "static_lru",    "static_pmem"
  };

  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "");
    return TCL_ERROR;
  }

  pRet = Tcl_NewObj();
  Tcl_IncrRefCount(pRet);
  for(ii=0; ii<8; ii++){
    Tcl_ListObjAppendElement(interp, pRet, Tcl_NewStringObj(aName[ii], -1));
    Tcl_ListObjAppendElement(interp, pRet, Tcl_NewIntObj(g.aCounter[ii]));
  }
  Tcl_SetObjResult(interp, pRet);
  Tcl_DecrRefCount(pRet);

  return TCL_OK;
................................................................................
  int ii;

  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "");
    return TCL_ERROR;
  }

  for(ii=0; ii<8; ii++){
    g.aCounter[ii] = 0;
  }
  return TCL_OK;
}

/*
** Create and free a mutex.  Return the mutex pointer.  The pointer
................................................................................
    db = *((sqlite3 **)info.objClientData);
  }else{
    db = (sqlite3*)sqlite3TestTextToPtr(zCmd);
  }
  assert( db );
  return db;
}



















































static int test_enter_db_mutex(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
................................................................................
  static struct {
    char *zName;
    Tcl_ObjCmdProc *xProc;
  } aCmd[] = {
    { "sqlite3_shutdown",        (Tcl_ObjCmdProc*)test_shutdown },
    { "sqlite3_initialize",      (Tcl_ObjCmdProc*)test_initialize },
    { "sqlite3_config",          (Tcl_ObjCmdProc*)test_config },




    { "enter_db_mutex",          (Tcl_ObjCmdProc*)test_enter_db_mutex },
    { "leave_db_mutex",          (Tcl_ObjCmdProc*)test_leave_db_mutex },

    { "alloc_dealloc_mutex",     (Tcl_ObjCmdProc*)test_alloc_mutex },
    { "install_mutex_counters",  (Tcl_ObjCmdProc*)test_install_mutex_counters },
    { "read_mutex_counters",     (Tcl_ObjCmdProc*)test_read_mutex_counters },

#include "tcl.h"
#include "sqlite3.h"
#include "sqliteInt.h"
#include <stdlib.h>
#include <assert.h>
#include <string.h>

#define MAX_MUTEXES        (SQLITE_MUTEX_STATIC_VFS3+1)
#define STATIC_MUTEXES     (MAX_MUTEXES-(SQLITE_MUTEX_RECURSIVE+1))

/* defined in main.c */
extern const char *sqlite3ErrName(int);

static const char *aName[MAX_MUTEXES+1] = {
  "fast",        "recursive",   "static_master", "static_mem",
  "static_open", "static_prng", "static_lru",    "static_pmem",
  "static_app1", "static_app2", "static_app3",   "static_vfs1",
  "static_vfs2", "static_vfs3", 0
};

/* A countable mutex */
struct sqlite3_mutex {
  sqlite3_mutex *pReal;
  int eType;
};

/* State variables */
static struct test_mutex_globals {
  int isInstalled;           /* True if installed */
  int disableInit;           /* True to cause sqlite3_initalize() to fail */
  int disableTry;            /* True to force sqlite3_mutex_try() to fail */
  int isInit;                /* True if initialized */
  sqlite3_mutex_methods m;   /* Interface to "real" mutex system */
  int aCounter[MAX_MUTEXES]; /* Number of grabs of each type of mutex */
  sqlite3_mutex aStatic[STATIC_MUTEXES]; /* The static mutexes */
} g = {0};

/* Return true if the countable mutex is currently held */
static int counterMutexHeld(sqlite3_mutex *p){
  return g.m.xMutexHeld(p->pReal);
}

................................................................................
** Allocate a countable mutex
*/
static sqlite3_mutex *counterMutexAlloc(int eType){
  sqlite3_mutex *pReal;
  sqlite3_mutex *pRet = 0;

  assert( g.isInit );
  assert( eType>=SQLITE_MUTEX_FAST );
  assert( eType<=SQLITE_MUTEX_STATIC_VFS3 );

  pReal = g.m.xMutexAlloc(eType);
  if( !pReal ) return 0;

  if( eType==SQLITE_MUTEX_FAST || eType==SQLITE_MUTEX_RECURSIVE ){
    pRet = (sqlite3_mutex *)malloc(sizeof(sqlite3_mutex));
  }else{
    int eStaticType = eType - (MAX_MUTEXES - STATIC_MUTEXES);
    assert( eStaticType>=0 );
    assert( eStaticType<STATIC_MUTEXES );
    pRet = &g.aStatic[eStaticType];
  }

  pRet->eType = eType;
  pRet->pReal = pReal;
  return pRet;
}

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

/*
** Enter a countable mutex.  Block until entry is safe.
*/
static void counterMutexEnter(sqlite3_mutex *p){
  assert( g.isInit );
  assert( p->eType>=0 );
  assert( p->eType<MAX_MUTEXES );
  g.aCounter[p->eType]++;
  g.m.xMutexEnter(p->pReal);
}

/*
** Try to enter a mutex.  Return true on success.
*/
static int counterMutexTry(sqlite3_mutex *p){
  assert( g.isInit );
  assert( p->eType>=0 );
  assert( p->eType<MAX_MUTEXES );
  g.aCounter[p->eType]++;
  if( g.disableTry ) return SQLITE_BUSY;
  return g.m.xMutexTry(p->pReal);
}

/* Leave a mutex
*/
................................................................................
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  Tcl_Obj *pRet;
  int ii;





  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "");
    return TCL_ERROR;
  }

  pRet = Tcl_NewObj();
  Tcl_IncrRefCount(pRet);
  for(ii=0; ii<MAX_MUTEXES; ii++){
    Tcl_ListObjAppendElement(interp, pRet, Tcl_NewStringObj(aName[ii], -1));
    Tcl_ListObjAppendElement(interp, pRet, Tcl_NewIntObj(g.aCounter[ii]));
  }
  Tcl_SetObjResult(interp, pRet);
  Tcl_DecrRefCount(pRet);

  return TCL_OK;
................................................................................
  int ii;

  if( objc!=1 ){
    Tcl_WrongNumArgs(interp, 1, objv, "");
    return TCL_ERROR;
  }

  for(ii=0; ii<MAX_MUTEXES; ii++){
    g.aCounter[ii] = 0;
  }
  return TCL_OK;
}

/*
** Create and free a mutex.  Return the mutex pointer.  The pointer
................................................................................
    db = *((sqlite3 **)info.objClientData);
  }else{
    db = (sqlite3*)sqlite3TestTextToPtr(zCmd);
  }
  assert( db );
  return db;
}

static sqlite3_mutex *getStaticMutexPointer(
  Tcl_Interp *pInterp,
  Tcl_Obj *pObj
){
  int iMutex;
  if( Tcl_GetIndexFromObj(pInterp, pObj, aName, "mutex name", 0, &iMutex) ){
    return 0;
  }
  assert( iMutex!=SQLITE_MUTEX_FAST && iMutex!=SQLITE_MUTEX_RECURSIVE );
  return counterMutexAlloc(iMutex);
}

static int test_enter_static_mutex(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  sqlite3_mutex *pMutex;
  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "NAME");
    return TCL_ERROR;
  }
  pMutex = getStaticMutexPointer(interp, objv[1]);
  if( !pMutex ){
    return TCL_ERROR;
  }
  sqlite3_mutex_enter(pMutex);
  return TCL_OK;
}

static int test_leave_static_mutex(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
  sqlite3_mutex *pMutex;
  if( objc!=2 ){
    Tcl_WrongNumArgs(interp, 1, objv, "NAME");
    return TCL_ERROR;
  }
  pMutex = getStaticMutexPointer(interp, objv[1]);
  if( !pMutex ){
    return TCL_ERROR;
  }
  sqlite3_mutex_leave(pMutex);
  return TCL_OK;
}

static int test_enter_db_mutex(
  void * clientData,
  Tcl_Interp *interp,
  int objc,
  Tcl_Obj *CONST objv[]
){
................................................................................
  static struct {
    char *zName;
    Tcl_ObjCmdProc *xProc;
  } aCmd[] = {
    { "sqlite3_shutdown",        (Tcl_ObjCmdProc*)test_shutdown },
    { "sqlite3_initialize",      (Tcl_ObjCmdProc*)test_initialize },
    { "sqlite3_config",          (Tcl_ObjCmdProc*)test_config },

    { "enter_static_mutex",      (Tcl_ObjCmdProc*)test_enter_static_mutex },
    { "leave_static_mutex",      (Tcl_ObjCmdProc*)test_leave_static_mutex },

    { "enter_db_mutex",          (Tcl_ObjCmdProc*)test_enter_db_mutex },
    { "leave_db_mutex",          (Tcl_ObjCmdProc*)test_leave_db_mutex },

    { "alloc_dealloc_mutex",     (Tcl_ObjCmdProc*)test_alloc_mutex },
    { "install_mutex_counters",  (Tcl_ObjCmdProc*)test_install_mutex_counters },
    { "read_mutex_counters",     (Tcl_ObjCmdProc*)test_read_mutex_counters },

** Read or write a four-byte big-endian integer value.
*/
u32 sqlite3Get4byte(const u8 *p){
#if SQLITE_BYTEORDER==4321
  u32 x;
  memcpy(&x,p,4);
  return x;
#elif SQLITE_BYTEORDER==1234 && defined(__GNUC__)
  u32 x;
  memcpy(&x,p,4);
  return __builtin_bswap32(x);
#elif SQLITE_BYTEORDER==1234 && defined(_MSC_VER) && _MSC_VER>=1300
  u32 x;
  memcpy(&x,p,4);
  return _byteswap_ulong(x);
................................................................................
  testcase( p[0]&0x80 );
  return ((unsigned)p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
#endif
}
void sqlite3Put4byte(unsigned char *p, u32 v){
#if SQLITE_BYTEORDER==4321
  memcpy(p,&v,4);
#elif SQLITE_BYTEORDER==1234 && defined(__GNUC__)
  u32 x = __builtin_bswap32(v);
  memcpy(p,&x,4);
#elif SQLITE_BYTEORDER==1234 && defined(_MSC_VER) && _MSC_VER>=1300
  u32 x = _byteswap_ulong(v);
  memcpy(p,&x,4);
#else
  p[0] = (u8)(v>>24);

** Read or write a four-byte big-endian integer value.
*/
u32 sqlite3Get4byte(const u8 *p){
#if SQLITE_BYTEORDER==4321
  u32 x;
  memcpy(&x,p,4);
  return x;
#elif SQLITE_BYTEORDER==1234 && defined(__GNUC__) && GCC_VERSION>=4003000
  u32 x;
  memcpy(&x,p,4);
  return __builtin_bswap32(x);
#elif SQLITE_BYTEORDER==1234 && defined(_MSC_VER) && _MSC_VER>=1300
  u32 x;
  memcpy(&x,p,4);
  return _byteswap_ulong(x);
................................................................................
  testcase( p[0]&0x80 );
  return ((unsigned)p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3];
#endif
}
void sqlite3Put4byte(unsigned char *p, u32 v){
#if SQLITE_BYTEORDER==4321
  memcpy(p,&v,4);
#elif SQLITE_BYTEORDER==1234 && defined(__GNUC__) && GCC_VERSION>=4003000
  u32 x = __builtin_bswap32(v);
  memcpy(p,&x,4);
#elif SQLITE_BYTEORDER==1234 && defined(_MSC_VER) && _MSC_VER>=1300
  u32 x = _byteswap_ulong(v);
  memcpy(p,&x,4);
#else
  p[0] = (u8)(v>>24);

    sqlite3_log(SQLITE_MISUSE, "API called with NULL prepared statement");
    return 1;
  }else{
    return vdbeSafety(p);
  }
}


























/*
** The following routine destroys a virtual machine that is created by
** the sqlite3_compile() routine. The integer returned is an SQLITE_
** success/failure code that describes the result of executing the virtual
** machine.
**
** This routine sets the error code and string returned by
................................................................................
    ** pointer is a harmless no-op. */
    rc = SQLITE_OK;
  }else{
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3 *db = v->db;
    if( vdbeSafety(v) ) return SQLITE_MISUSE_BKPT;
    sqlite3_mutex_enter(db->mutex);

    rc = sqlite3VdbeFinalize(v);
    rc = sqlite3ApiExit(db, rc);
    sqlite3LeaveMutexAndCloseZombie(db);
  }
  return rc;
}

................................................................................
*/
int sqlite3_reset(sqlite3_stmt *pStmt){
  int rc;
  if( pStmt==0 ){
    rc = SQLITE_OK;
  }else{
    Vdbe *v = (Vdbe*)pStmt;

    sqlite3_mutex_enter(v->db->mutex);

    rc = sqlite3VdbeReset(v);
    sqlite3VdbeRewind(v);
    assert( (rc & (v->db->errMask))==rc );
    rc = sqlite3ApiExit(v->db, rc);
    sqlite3_mutex_leave(v->db->mutex);
  }
  return rc;
}

/*
** Set all the parameters in the compiled SQL statement to NULL.
*/
................................................................................
        rc = db->xWalCallback(db->pWalArg, db, db->aDb[i].zName, nEntry);
      }
    }
  }
#endif
  return rc;
}


/*
** Execute the statement pStmt, either until a row of data is ready, the
** statement is completely executed or an error occurs.
**
** This routine implements the bulk of the logic behind the sqlite_step()
** API.  The only thing omitted is the automatic recompile if a 
................................................................................
    }

    assert( db->nVdbeWrite>0 || db->autoCommit==0 
        || (db->nDeferredCons==0 && db->nDeferredImmCons==0)
    );

#ifndef SQLITE_OMIT_TRACE
    if( db->xProfile && !db->init.busy ){
      sqlite3OsCurrentTimeInt64(db->pVfs, &p->startTime);


    }
#endif

    db->nVdbeActive++;
    if( p->readOnly==0 ) db->nVdbeWrite++;
    if( p->bIsReader ) db->nVdbeRead++;
    p->pc = 0;
................................................................................
  {
    db->nVdbeExec++;
    rc = sqlite3VdbeExec(p);
    db->nVdbeExec--;
  }

#ifndef SQLITE_OMIT_TRACE
  /* Invoke the profile callback if there is one
  */
  if( rc!=SQLITE_ROW && db->xProfile && !db->init.busy && p->zSql ){
    sqlite3_int64 iNow;
    sqlite3OsCurrentTimeInt64(db->pVfs, &iNow);
    db->xProfile(db->pProfileArg, p->zSql, (iNow - p->startTime)*1000000);
  }

#endif

  if( rc==SQLITE_DONE ){
    assert( p->rc==SQLITE_OK );
    p->rc = doWalCallbacks(db);
    if( p->rc!=SQLITE_OK ){
      rc = SQLITE_ERROR;

    sqlite3_log(SQLITE_MISUSE, "API called with NULL prepared statement");
    return 1;
  }else{
    return vdbeSafety(p);
  }
}

#ifndef SQLITE_OMIT_TRACE
/*
** Invoke the profile callback.  This routine is only called if we already
** know that the profile callback is defined and needs to be invoked.
*/
static SQLITE_NOINLINE void invokeProfileCallback(sqlite3 *db, Vdbe *p){
  sqlite3_int64 iNow;
  assert( p->startTime>0 );
  assert( db->xProfile!=0 );
  assert( db->init.busy==0 );
  assert( p->zSql!=0 );
  sqlite3OsCurrentTimeInt64(db->pVfs, &iNow);
  db->xProfile(db->pProfileArg, p->zSql, (iNow - p->startTime)*1000000);
  p->startTime = 0;
}
/*
** The checkProfileCallback(DB,P) macro checks to see if a profile callback
** is needed, and it invokes the callback if it is needed.
*/
# define checkProfileCallback(DB,P) \
   if( ((P)->startTime)>0 ){ invokeProfileCallback(DB,P); }
#else
# define checkProfileCallback(DB,P)  /*no-op*/
#endif

/*
** The following routine destroys a virtual machine that is created by
** the sqlite3_compile() routine. The integer returned is an SQLITE_
** success/failure code that describes the result of executing the virtual
** machine.
**
** This routine sets the error code and string returned by
................................................................................
    ** pointer is a harmless no-op. */
    rc = SQLITE_OK;
  }else{
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3 *db = v->db;
    if( vdbeSafety(v) ) return SQLITE_MISUSE_BKPT;
    sqlite3_mutex_enter(db->mutex);
    checkProfileCallback(db, v);
    rc = sqlite3VdbeFinalize(v);
    rc = sqlite3ApiExit(db, rc);
    sqlite3LeaveMutexAndCloseZombie(db);
  }
  return rc;
}

................................................................................
*/
int sqlite3_reset(sqlite3_stmt *pStmt){
  int rc;
  if( pStmt==0 ){
    rc = SQLITE_OK;
  }else{
    Vdbe *v = (Vdbe*)pStmt;
    sqlite3 *db = v->db;
    sqlite3_mutex_enter(db->mutex);
    checkProfileCallback(db, v);
    rc = sqlite3VdbeReset(v);
    sqlite3VdbeRewind(v);
    assert( (rc & (db->errMask))==rc );
    rc = sqlite3ApiExit(db, rc);
    sqlite3_mutex_leave(db->mutex);
  }
  return rc;
}

/*
** Set all the parameters in the compiled SQL statement to NULL.
*/
................................................................................
        rc = db->xWalCallback(db->pWalArg, db, db->aDb[i].zName, nEntry);
      }
    }
  }
#endif
  return rc;
}


/*
** Execute the statement pStmt, either until a row of data is ready, the
** statement is completely executed or an error occurs.
**
** This routine implements the bulk of the logic behind the sqlite_step()
** API.  The only thing omitted is the automatic recompile if a 
................................................................................
    }

    assert( db->nVdbeWrite>0 || db->autoCommit==0 
        || (db->nDeferredCons==0 && db->nDeferredImmCons==0)
    );

#ifndef SQLITE_OMIT_TRACE
    if( db->xProfile && !db->init.busy && p->zSql ){
      sqlite3OsCurrentTimeInt64(db->pVfs, &p->startTime);
    }else{
      assert( p->startTime==0 );
    }
#endif

    db->nVdbeActive++;
    if( p->readOnly==0 ) db->nVdbeWrite++;
    if( p->bIsReader ) db->nVdbeRead++;
    p->pc = 0;
................................................................................
  {
    db->nVdbeExec++;
    rc = sqlite3VdbeExec(p);
    db->nVdbeExec--;
  }

#ifndef SQLITE_OMIT_TRACE
  /* If the statement completed successfully, invoke the profile callback */






  if( rc!=SQLITE_ROW ) checkProfileCallback(db, p);
#endif

  if( rc==SQLITE_DONE ){
    assert( p->rc==SQLITE_OK );
    p->rc = doWalCallbacks(db);
    if( p->rc!=SQLITE_OK ){
      rc = SQLITE_ERROR;

  ** the unnecessary initialization has a measurable negative performance
  ** impact, since this routine is a very high runner.  And so, we choose
  ** to ignore the compiler warnings and leave this variable uninitialized.
  */
  /*  mem1.u.i = 0;  // not needed, here to silence compiler warning */
  
  idx1 = getVarint32(aKey1, szHdr1);

  d1 = szHdr1;
  assert( pKeyInfo->nField+pKeyInfo->nXField>=pPKey2->nField || CORRUPT_DB );
  assert( pKeyInfo->aSortOrder!=0 );
  assert( pKeyInfo->nField>0 );
  assert( idx1<=szHdr1 || CORRUPT_DB );
  do{
    u32 serial_type1;

  ** the unnecessary initialization has a measurable negative performance
  ** impact, since this routine is a very high runner.  And so, we choose
  ** to ignore the compiler warnings and leave this variable uninitialized.
  */
  /*  mem1.u.i = 0;  // not needed, here to silence compiler warning */
  
  idx1 = getVarint32(aKey1, szHdr1);
  if( szHdr1>98307 ) return SQLITE_CORRUPT;
  d1 = szHdr1;
  assert( pKeyInfo->nField+pKeyInfo->nXField>=pPKey2->nField || CORRUPT_DB );
  assert( pKeyInfo->aSortOrder!=0 );
  assert( pKeyInfo->nField>0 );
  assert( idx1<=szHdr1 || CORRUPT_DB );
  do{
    u32 serial_type1;

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

set ::testprefix fts3fault

# If SQLITE_ENABLE_FTS3 is not defined, omit this file.
ifcapable !fts3 { finish_test ; return }



# Test error handling in the sqlite3Fts3Init() function. This is the 
# function that registers the FTS3 module and various support functions
# with SQLite.
#
do_faultsim_test 1 -body { 
  sqlite3 db test.db 
................................................................................
  execsql { CREATE VIRTUAL TABLE t1 USING fts4(a, b, matchnfo=fts3) }
} -test {
  faultsim_test_result {1 {unrecognized parameter: matchnfo=fts3}} \
                       {1 {vtable constructor failed: t1}} \
                       {1 {SQL logic error or missing database}}
}




proc mit {blob} {
  set scan(littleEndian) i*
  set scan(bigEndian) I*
  binary scan $blob $scan($::tcl_platform(byteOrder)) r
  return $r
}

................................................................................
  execsql "INSERT INTO t8 VALUES('[string repeat {c } 50000]')"
  execsql "INSERT INTO t8 VALUES('d d d')"
  execsql "INSERT INTO t8 VALUES('e e e')"
  execsql "INSERT INTO t8(t8) VALUES('optimize')"
  faultsim_save_and_close
} {}

do_faultsim_test 8.1 -prep { 
  faultsim_restore_and_reopen
  db func mit mit
} -body {
  execsql { SELECT mit(matchinfo(t8, 'x')) FROM t8 WHERE t8 MATCH 'a b c' }
} -test {
  faultsim_test_result {0 {{1 1 1 1 4 2 1 5 5}}}
}

do_faultsim_test 8.2 -faults oom-t* -prep { 
  faultsim_restore_and_reopen
  db func mit mit
} -body {
  execsql { SELECT mit(matchinfo(t8, 's')) FROM t8 WHERE t8 MATCH 'a b c' }
} -test {
  faultsim_test_result {0 3}

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

set ::testprefix fts3fault

# If SQLITE_ENABLE_FTS3 is not defined, omit this file.
ifcapable !fts3 { finish_test ; return }

if 0 {

# Test error handling in the sqlite3Fts3Init() function. This is the 
# function that registers the FTS3 module and various support functions
# with SQLite.
#
do_faultsim_test 1 -body { 
  sqlite3 db test.db 
................................................................................
  execsql { CREATE VIRTUAL TABLE t1 USING fts4(a, b, matchnfo=fts3) }
} -test {
  faultsim_test_result {1 {unrecognized parameter: matchnfo=fts3}} \
                       {1 {vtable constructor failed: t1}} \
                       {1 {SQL logic error or missing database}}
}


}

proc mit {blob} {
  set scan(littleEndian) i*
  set scan(bigEndian) I*
  binary scan $blob $scan($::tcl_platform(byteOrder)) r
  return $r
}

................................................................................
  execsql "INSERT INTO t8 VALUES('[string repeat {c } 50000]')"
  execsql "INSERT INTO t8 VALUES('d d d')"
  execsql "INSERT INTO t8 VALUES('e e e')"
  execsql "INSERT INTO t8(t8) VALUES('optimize')"
  faultsim_save_and_close
} {}

do_faultsim_test 8.1 -faults oom-t* -prep { 
  faultsim_restore_and_reopen
  db func mit mit
} -body {
  execsql { SELECT mit(matchinfo(t8, 'x')) FROM t8 WHERE t8 MATCH 'a b c' }
} -test {
  faultsim_test_result {0 {{1 1 1 1 4 2 1 5 5}}}
}

do_faultsim_test 8.2 -faults oom-t* -prep { 
  faultsim_restore_and_reopen
  db func mit mit
} -body {
  execsql { SELECT mit(matchinfo(t8, 's')) FROM t8 WHERE t8 MATCH 'a b c' }
} -test {
  faultsim_test_result {0 3}

# 2010 November 02
#
# 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

# If SQLITE_ENABLE_FTS3 is not defined, omit this file.
ifcapable !fts3 { finish_test ; return }

set testprefix fts3offsets
set sqlite_fts3_enable_parentheses 1

proc extract {offsets text} {
  set res ""

  set off [list]
  foreach {t i s n} $offsets {
    lappend off [list $s $n]
  }
  set off [lsort -integer -index 0 $off]

  set iOff 0
  foreach e $off {
    foreach {s n} $e {}
    append res [string range $text $iOff $s-1]
    append res "("
    append res [string range $text $s [expr $s+$n-1]]
    append res ")"
    set iOff [expr $s+$n]
  }
  append res [string range $text $iOff end]
  
  set res
}
db func extract extract


do_execsql_test 1.1.0 {
  CREATE VIRTUAL TABLE xx USING fts3(x);
  INSERT INTO xx VALUES('A x x x B C x x');
  INSERT INTO xx VALUES('A B C x B x x C');
  INSERT INTO xx VALUES('A x x B C x x x');
}
do_execsql_test 1.1.1 {
  SELECT oid,extract(offsets(xx), x) FROM xx WHERE xx MATCH 'a OR (b NEAR/1 c)';
} {
  1 {(A) x x x (B) (C) x x} 
  2 {(A) (B) (C) x (B) x x C} 
  3 {(A) x x (B) (C) x x x}
}

do_execsql_test 1.2 {
  DELETE FROM xx;
  INSERT INTO xx VALUES('A x x x B C x x');
  INSERT INTO xx VALUES('A x x C x x x C');
  INSERT INTO xx VALUES('A x x B C x x x');
}
do_execsql_test 1.2.1 {
  SELECT oid,extract(offsets(xx), x) FROM xx WHERE xx MATCH 'a OR (b NEAR/1 c)';
} {
  1 {(A) x x x (B) (C) x x}
  2 {(A) x x C x x x C} 
  3 {(A) x x (B) (C) x x x}
}

do_execsql_test 1.3 {
  DELETE FROM xx;
  INSERT INTO xx(rowid, x) VALUES(1, 'A B C');
  INSERT INTO xx(rowid, x) VALUES(2, 'A x');
  INSERT INTO xx(rowid, x) VALUES(3, 'A B C');
  INSERT INTO xx(rowid, x) VALUES(4, 'A B C x x x x x x x B');
  INSERT INTO xx(rowid, x) VALUES(5, 'A x x x x x x x x x C');
  INSERT INTO xx(rowid, x) VALUES(6, 'A x x x x x x x x x x x B');
  INSERT INTO xx(rowid, x) VALUES(7, 'A B C');
}
do_execsql_test 1.3.1 {
  SELECT oid,extract(offsets(xx), x) FROM xx WHERE xx MATCH 'a OR (b NEAR/1 c)';
} {
  1 {(A) (B) (C)}
  2 {(A) x}
  3 {(A) (B) (C)}
  4 {(A) (B) (C) x x x x x x x B}
  5 {(A) x x x x x x x x x C}
  6 {(A) x x x x x x x x x x x B} 
  7 {(A) (B) (C)}
}


do_execsql_test 1.4 {
  DELETE FROM xx;
  INSERT INTO xx(rowid, x) VALUES(7, 'A B C');
  INSERT INTO xx(rowid, x) VALUES(6, 'A x');
  INSERT INTO xx(rowid, x) VALUES(5, 'A B C');
  INSERT INTO xx(rowid, x) VALUES(4, 'A B C x x x x x x x B');
  INSERT INTO xx(rowid, x) VALUES(3, 'A x x x x x x x x x C');
  INSERT INTO xx(rowid, x) VALUES(2, 'A x x x x x x x x x x x B');
  INSERT INTO xx(rowid, x) VALUES(1, 'A B C');
}
do_execsql_test 1.4.1 {
  SELECT oid,extract(offsets(xx), x) FROM xx WHERE xx MATCH 'a OR (b NEAR/1 c)'
  ORDER BY docid DESC;
} {
  7 {(A) (B) (C)}
  6 {(A) x}
  5 {(A) (B) (C)}
  4 {(A) (B) (C) x x x x x x x B}
  3 {(A) x x x x x x x x x C}
  2 {(A) x x x x x x x x x x x B} 
  1 {(A) (B) (C)}
}


set sqlite_fts3_enable_parentheses 0
finish_test

    execsql {
      PRAGMA auto_vacuum = full;
      CREATE TABLE t1(a);
      INSERT INTO t1 VALUES(randstr(1000,1000));
      INSERT INTO t1 VALUES(randstr(1000,1000));
      INSERT INTO t1 VALUES(randstr(1000,1000));
    }
    set memused [lindex [sqlite3_status SQLITE_STATUS_MEMORY_USED 0] 1]
    set pgovfl [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_OVERFLOW 0] 1]
    execsql { DELETE FROM t1 }

    set memused2 [lindex [sqlite3_status SQLITE_STATUS_MEMORY_USED 0] 1]
    expr {($memused2 + 2048 < $memused) || $pgovfl==0}
  } {1}
}

} ;# ifcapable memorydb

finish_test

    execsql {
      PRAGMA auto_vacuum = full;
      CREATE TABLE t1(a);
      INSERT INTO t1 VALUES(randstr(1000,1000));
      INSERT INTO t1 VALUES(randstr(1000,1000));
      INSERT INTO t1 VALUES(randstr(1000,1000));
    }
    set before [db one {PRAGMA page_count}]

    execsql { DELETE FROM t1 }
    set after [db one {PRAGMA page_count}]
    expr {$before>$after}

  } {1}
}

} ;# ifcapable memorydb

finish_test

set xtra_size 290

# Test 1:  Both PAGECACHE and SCRATCH are shut down.
#
db close
sqlite3_shutdown
sqlite3_config_lookaside 0 0

sqlite3_initialize
reset_highwater_marks
build_test_db memsubsys1-1 {PRAGMA page_size=1024}
do_test memsubsys1-1.3 {
  set pg_used [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_USED 0] 2]
} 0
do_test memsubsys1-1.4 {
................................................................................

# Test 3:  Activate PAGECACHE with 20 pages but use the wrong page size
# so that PAGECACHE is not used.
#
db close
sqlite3_shutdown
sqlite3_config_pagecache [expr 512+$xtra_size] 20

sqlite3_initialize
reset_highwater_marks
build_test_db memsubsys1-3.1 {PRAGMA page_size=1024}
#show_memstats
do_test memsubsys1-3.1.3 {
  set pg_used [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_USED 0] 2]
} 0
do_test memsubsys1-3.1.4 {
  set overflow [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_OVERFLOW 0] 2]
  # Note:  The measured PAGECACHE_OVERFLOW is amount malloc() returns, not what
  # was requested.  System malloc() implementations might (arbitrarily) return
................................................................................

db close
sqlite3_shutdown
sqlite3_config_memstatus 1
sqlite3_config_pagecache 0 0
sqlite3_config_scratch 0 0
sqlite3_config_lookaside 100 500

sqlite3_initialize
autoinstall_test_functions
finish_test

set xtra_size 290

# Test 1:  Both PAGECACHE and SCRATCH are shut down.
#
db close
sqlite3_shutdown
sqlite3_config_lookaside 0 0
sqlite3_config_pagecache 0 0
sqlite3_initialize
reset_highwater_marks
build_test_db memsubsys1-1 {PRAGMA page_size=1024}
do_test memsubsys1-1.3 {
  set pg_used [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_USED 0] 2]
} 0
do_test memsubsys1-1.4 {
................................................................................

# Test 3:  Activate PAGECACHE with 20 pages but use the wrong page size
# so that PAGECACHE is not used.
#
db close
sqlite3_shutdown
sqlite3_config_pagecache [expr 512+$xtra_size] 20
sqlite3_config singlethread
sqlite3_initialize
reset_highwater_marks
build_test_db memsubsys1-3.1 {PRAGMA page_size=1024}

do_test memsubsys1-3.1.3 {
  set pg_used [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_USED 0] 2]
} 0
do_test memsubsys1-3.1.4 {
  set overflow [lindex [sqlite3_status SQLITE_STATUS_PAGECACHE_OVERFLOW 0] 2]
  # Note:  The measured PAGECACHE_OVERFLOW is amount malloc() returns, not what
  # was requested.  System malloc() implementations might (arbitrarily) return
................................................................................

db close
sqlite3_shutdown
sqlite3_config_memstatus 1
sqlite3_config_pagecache 0 0
sqlite3_config_scratch 0 0
sqlite3_config_lookaside 100 500
sqlite3_config serialized
sqlite3_initialize
autoinstall_test_functions
finish_test

    set var($name) $value
    incr var(total) $value
  }
}

#-------------------------------------------------------------------------
# Tests mutex1-1.* test that sqlite3_config() returns SQLITE_MISUSE if
# is called at the wrong time. And that the first time sqlite3_initialize 
# is called it obtains the 'static_master' mutex 3 times and a recursive
# mutex (sqlite3Config.pInitMutex) twice. Subsequent calls are no-ops 
# that do not require any mutexes.
#
do_test mutex1-1.0 {
  install_mutex_counters 1
} {SQLITE_MISUSE}

do_test mutex1-1.1 {
................................................................................
#   * Single-threaded mode.
#
ifcapable threadsafe&&shared_cache {
  set enable_shared_cache [sqlite3_enable_shared_cache 1]
  foreach {mode mutexes} {
    singlethread {}
    multithread  {

      fast static_lru static_master static_mem static_open static_prng 

      static_pmem
    }
    serialized  {

      fast recursive static_lru static_master static_mem static_open 
      static_prng static_pmem

    }
  } {

    do_test mutex1.2.$mode.1 {
      catch {db close}
      sqlite3_shutdown
      sqlite3_config $mode
................................................................................
      db eval {
        INSERT INTO abc VALUES(1, 2, 3);
      }
    } {}
    ifcapable !memorymanage {
      regsub { static_lru} $mutexes {} mutexes
    }

    do_test mutex1.2.$mode.3 {


















      mutex_counters counters
  
      set res [list]
      foreach {key value} [array get counters] {
        if {$key ne "total" && $value > 0} {
          lappend res $key
        }
      }
      lsort $res

    set var($name) $value
    incr var(total) $value
  }
}

#-------------------------------------------------------------------------
# Tests mutex1-1.* test that sqlite3_config() returns SQLITE_MISUSE if
# is called at the wrong time. And that the first time sqlite3_initialize
# is called it obtains the 'static_master' mutex 3 times and a recursive
# mutex (sqlite3Config.pInitMutex) twice. Subsequent calls are no-ops
# that do not require any mutexes.
#
do_test mutex1-1.0 {
  install_mutex_counters 1
} {SQLITE_MISUSE}

do_test mutex1-1.1 {
................................................................................
#   * Single-threaded mode.
#
ifcapable threadsafe&&shared_cache {
  set enable_shared_cache [sqlite3_enable_shared_cache 1]
  foreach {mode mutexes} {
    singlethread {}
    multithread  {
      fast static_app1 static_app2 static_app3
      static_lru static_master static_mem static_open
      static_prng static_pmem static_vfs1 static_vfs2
      static_vfs3
    }
    serialized  {
      fast recursive static_app1 static_app2
      static_app3 static_lru static_master static_mem
      static_open static_prng static_pmem static_vfs1
      static_vfs2 static_vfs3
    }
  } {

    do_test mutex1.2.$mode.1 {
      catch {db close}
      sqlite3_shutdown
      sqlite3_config $mode
................................................................................
      db eval {
        INSERT INTO abc VALUES(1, 2, 3);
      }
    } {}
    ifcapable !memorymanage {
      regsub { static_lru} $mutexes {} mutexes
    }
    if {$mode ne "singlethread"} {
      do_test mutex1.2.$mode.3 {
        #
        # NOTE: Make sure all the app and vfs mutexes get used.
        #
        enter_static_mutex static_app1
        leave_static_mutex static_app1
        enter_static_mutex static_app2
        leave_static_mutex static_app2
        enter_static_mutex static_app3
        leave_static_mutex static_app3
        enter_static_mutex static_vfs1
        leave_static_mutex static_vfs1
        enter_static_mutex static_vfs2
        leave_static_mutex static_vfs2
        enter_static_mutex static_vfs3
        leave_static_mutex static_vfs3
      } {}
    }
    do_test mutex1.2.$mode.4 {
      mutex_counters counters

      set res [list]
      foreach {key value} [array get counters] {
        if {$key ne "total" && $value > 0} {
          lappend res $key
        }
      }
      lsort $res

# pages are being used for cache.
#
do_test pcache2-1.1 {
  db close
  sqlite3_reset_auto_extension
  sqlite3_shutdown
  sqlite3_config_pagecache 6000 100

  sqlite3_initialize
  autoinstall_test_functions
  sqlite3_status SQLITE_STATUS_PAGECACHE_USED 1
  sqlite3_status SQLITE_STATUS_PAGECACHE_USED 0
} {0 0 0}

# Open up two database connections to separate files.
................................................................................
} {0 13 13}

db close
catch {db2 close}
sqlite3_reset_auto_extension
sqlite3_shutdown
sqlite3_config_pagecache 0 0

sqlite3_initialize
autoinstall_test_functions

finish_test

# pages are being used for cache.
#
do_test pcache2-1.1 {
  db close
  sqlite3_reset_auto_extension
  sqlite3_shutdown
  sqlite3_config_pagecache 6000 100
  sqlite3_config singlethread
  sqlite3_initialize
  autoinstall_test_functions
  sqlite3_status SQLITE_STATUS_PAGECACHE_USED 1
  sqlite3_status SQLITE_STATUS_PAGECACHE_USED 0
} {0 0 0}

# Open up two database connections to separate files.
................................................................................
} {0 13 13}

db close
catch {db2 close}
sqlite3_reset_auto_extension
sqlite3_shutdown
sqlite3_config_pagecache 0 0
sqlite3_config serialized
sqlite3_initialize
autoinstall_test_functions

finish_test

  "  --exclusive         Enable locking_mode=EXCLUSIVE\n"
  "  --explain           Like --sqlonly but with added EXPLAIN keywords\n"
  "  --heap SZ MIN       Memory allocator uses SZ bytes & min allocation MIN\n"
  "  --incrvacuum        Enable incremenatal vacuum mode\n"
  "  --journal M         Set the journal_mode to M\n"
  "  --key KEY           Set the encryption key to KEY\n"
  "  --lookaside N SZ    Configure lookaside for N slots of SZ bytes each\n"


  "  --nosync            Set PRAGMA synchronous=OFF\n"
  "  --notnull           Add NOT NULL constraints to table columns\n"
  "  --pagesize N        Set the page size to N\n"
  "  --pcache N SZ       Configure N pages of pagecache each of size SZ bytes\n"
  "  --primarykey        Use PRIMARY KEY instead of UNIQUE where appropriate\n"
  "  --reprepare         Reprepare each statement upon every invocation\n"
  "  --scratch N SZ      Configure scratch memory for N slots of SZ bytes each\n"


  "  --sqlonly           No-op.  Only show the SQL that would have been run.\n"
  "  --shrink-memory     Invoke sqlite3_db_release_memory() frequently.\n"
  "  --size N            Relative test size.  Default=100\n"
  "  --stats             Show statistics at the end\n"
  "  --testset T         Run test-set T\n"
  "  --trace             Turn on SQL tracing\n"
  "  --threads N         Use up to N threads for sorting\n"
................................................................................
  int doIncrvac = 0;            /* True for --incrvacuum */
  const char *zJMode = 0;       /* Journal mode */
  const char *zKey = 0;         /* Encryption key */
  int nLook = 0, szLook = 0;    /* --lookaside configuration */
  int noSync = 0;               /* True for --nosync */
  int pageSize = 0;             /* Desired page size.  0 means default */
  int nPCache = 0, szPCache = 0;/* --pcache configuration */

  int nScratch = 0, szScratch=0;/* --scratch configuration */
  int showStats = 0;            /* True for --stats */
  int nThread = 0;              /* --threads value */
  const char *zTSet = "main";   /* Which --testset torun */
  int doTrace = 0;              /* True for --trace */
  const char *zEncoding = 0;    /* --utf16be or --utf16le */
  const char *zDbName = 0;      /* Name of the test database */
................................................................................
        if( i>=argc-1 ) fatal_error("missing argument on %s\n", argv[i]);
        zKey = argv[++i];
      }else if( strcmp(z,"lookaside")==0 ){
        if( i>=argc-2 ) fatal_error("missing arguments on %s\n", argv[i]);
        nLook = integerValue(argv[i+1]);
        szLook = integerValue(argv[i+2]);
        i += 2;




      }else if( strcmp(z,"nosync")==0 ){
        noSync = 1;
      }else if( strcmp(z,"notnull")==0 ){
        g.zNN = "NOT NULL";
#ifdef SQLITE_ENABLE_OTA
      }else if( strcmp(z,"ota")==0 ){
        sqlite3ota_create_vfs("ota", 0);
................................................................................
      }else if( strcmp(z,"pagesize")==0 ){
        if( i>=argc-1 ) fatal_error("missing argument on %s\n", argv[i]);
        pageSize = integerValue(argv[++i]);
      }else if( strcmp(z,"pcache")==0 ){
        if( i>=argc-2 ) fatal_error("missing arguments on %s\n", argv[i]);
        nPCache = integerValue(argv[i+1]);
        szPCache = integerValue(argv[i+2]);

        i += 2;
      }else if( strcmp(z,"primarykey")==0 ){
        g.zPK = "PRIMARY KEY";
      }else if( strcmp(z,"reprepare")==0 ){
        g.bReprepare = 1;
      }else if( strcmp(z,"scratch")==0 ){
        if( i>=argc-2 ) fatal_error("missing arguments on %s\n", argv[i]);
        nScratch = integerValue(argv[i+1]);
        szScratch = integerValue(argv[i+2]);
        i += 2;




      }else if( strcmp(z,"sqlonly")==0 ){
        g.bSqlOnly = 1;
      }else if( strcmp(z,"shrink-memory")==0 ){
        g.bMemShrink = 1;
      }else if( strcmp(z,"size")==0 ){
        if( i>=argc-1 ) fatal_error("missing argument on %s\n", argv[i]);
        g.szTest = integerValue(argv[++i]);
................................................................................
#if SQLITE_VERSION_NUMBER>=3006001
  if( nHeap>0 ){
    pHeap = malloc( nHeap );
    if( pHeap==0 ) fatal_error("cannot allocate %d-byte heap\n", nHeap);
    rc = sqlite3_config(SQLITE_CONFIG_HEAP, pHeap, nHeap, mnHeap);
    if( rc ) fatal_error("heap configuration failed: %d\n", rc);
  }

  if( nPCache>0 && szPCache>0 ){
    pPCache = malloc( nPCache*(sqlite3_int64)szPCache );
    if( pPCache==0 ) fatal_error("cannot allocate %lld-byte pcache\n",
                                 nPCache*(sqlite3_int64)szPCache);

    rc = sqlite3_config(SQLITE_CONFIG_PAGECACHE, pPCache, szPCache, nPCache);
    if( rc ) fatal_error("pcache configuration failed: %d\n", rc);
  }
  if( nScratch>0 && szScratch>0 ){
    pScratch = malloc( nScratch*(sqlite3_int64)szScratch );
    if( pScratch==0 ) fatal_error("cannot allocate %lld-byte scratch\n",
                                 nScratch*(sqlite3_int64)szScratch);

  "  --exclusive         Enable locking_mode=EXCLUSIVE\n"
  "  --explain           Like --sqlonly but with added EXPLAIN keywords\n"
  "  --heap SZ MIN       Memory allocator uses SZ bytes & min allocation MIN\n"
  "  --incrvacuum        Enable incremenatal vacuum mode\n"
  "  --journal M         Set the journal_mode to M\n"
  "  --key KEY           Set the encryption key to KEY\n"
  "  --lookaside N SZ    Configure lookaside for N slots of SZ bytes each\n"
  "  --multithread       Set multithreaded mode\n"
  "  --nomemstat         Disable memory statistics\n"
  "  --nosync            Set PRAGMA synchronous=OFF\n"
  "  --notnull           Add NOT NULL constraints to table columns\n"
  "  --pagesize N        Set the page size to N\n"
  "  --pcache N SZ       Configure N pages of pagecache each of size SZ bytes\n"
  "  --primarykey        Use PRIMARY KEY instead of UNIQUE where appropriate\n"
  "  --reprepare         Reprepare each statement upon every invocation\n"
  "  --scratch N SZ      Configure scratch memory for N slots of SZ bytes each\n"
  "  --serialized        Set serialized threading mode\n"
  "  --singlethread      Set single-threaded mode - disables all mutexing\n"
  "  --sqlonly           No-op.  Only show the SQL that would have been run.\n"
  "  --shrink-memory     Invoke sqlite3_db_release_memory() frequently.\n"
  "  --size N            Relative test size.  Default=100\n"
  "  --stats             Show statistics at the end\n"
  "  --testset T         Run test-set T\n"
  "  --trace             Turn on SQL tracing\n"
  "  --threads N         Use up to N threads for sorting\n"
................................................................................
  int doIncrvac = 0;            /* True for --incrvacuum */
  const char *zJMode = 0;       /* Journal mode */
  const char *zKey = 0;         /* Encryption key */
  int nLook = 0, szLook = 0;    /* --lookaside configuration */
  int noSync = 0;               /* True for --nosync */
  int pageSize = 0;             /* Desired page size.  0 means default */
  int nPCache = 0, szPCache = 0;/* --pcache configuration */
  int doPCache = 0;             /* True if --pcache is seen */
  int nScratch = 0, szScratch=0;/* --scratch configuration */
  int showStats = 0;            /* True for --stats */
  int nThread = 0;              /* --threads value */
  const char *zTSet = "main";   /* Which --testset torun */
  int doTrace = 0;              /* True for --trace */
  const char *zEncoding = 0;    /* --utf16be or --utf16le */
  const char *zDbName = 0;      /* Name of the test database */
................................................................................
        if( i>=argc-1 ) fatal_error("missing argument on %s\n", argv[i]);
        zKey = argv[++i];
      }else if( strcmp(z,"lookaside")==0 ){
        if( i>=argc-2 ) fatal_error("missing arguments on %s\n", argv[i]);
        nLook = integerValue(argv[i+1]);
        szLook = integerValue(argv[i+2]);
        i += 2;
      }else if( strcmp(z,"multithread")==0 ){
        sqlite3_config(SQLITE_CONFIG_MULTITHREAD);
      }else if( strcmp(z,"nomemstat")==0 ){
        sqlite3_config(SQLITE_CONFIG_MEMSTATUS, 0);
      }else if( strcmp(z,"nosync")==0 ){
        noSync = 1;
      }else if( strcmp(z,"notnull")==0 ){
        g.zNN = "NOT NULL";
#ifdef SQLITE_ENABLE_OTA
      }else if( strcmp(z,"ota")==0 ){
        sqlite3ota_create_vfs("ota", 0);
................................................................................
      }else if( strcmp(z,"pagesize")==0 ){
        if( i>=argc-1 ) fatal_error("missing argument on %s\n", argv[i]);
        pageSize = integerValue(argv[++i]);
      }else if( strcmp(z,"pcache")==0 ){
        if( i>=argc-2 ) fatal_error("missing arguments on %s\n", argv[i]);
        nPCache = integerValue(argv[i+1]);
        szPCache = integerValue(argv[i+2]);
        doPCache = 1;
        i += 2;
      }else if( strcmp(z,"primarykey")==0 ){
        g.zPK = "PRIMARY KEY";
      }else if( strcmp(z,"reprepare")==0 ){
        g.bReprepare = 1;
      }else if( strcmp(z,"scratch")==0 ){
        if( i>=argc-2 ) fatal_error("missing arguments on %s\n", argv[i]);
        nScratch = integerValue(argv[i+1]);
        szScratch = integerValue(argv[i+2]);
        i += 2;
      }else if( strcmp(z,"serialized")==0 ){
        sqlite3_config(SQLITE_CONFIG_SERIALIZED);
      }else if( strcmp(z,"singlethread")==0 ){
        sqlite3_config(SQLITE_CONFIG_SINGLETHREAD);
      }else if( strcmp(z,"sqlonly")==0 ){
        g.bSqlOnly = 1;
      }else if( strcmp(z,"shrink-memory")==0 ){
        g.bMemShrink = 1;
      }else if( strcmp(z,"size")==0 ){
        if( i>=argc-1 ) fatal_error("missing argument on %s\n", argv[i]);
        g.szTest = integerValue(argv[++i]);
................................................................................
#if SQLITE_VERSION_NUMBER>=3006001
  if( nHeap>0 ){
    pHeap = malloc( nHeap );
    if( pHeap==0 ) fatal_error("cannot allocate %d-byte heap\n", nHeap);
    rc = sqlite3_config(SQLITE_CONFIG_HEAP, pHeap, nHeap, mnHeap);
    if( rc ) fatal_error("heap configuration failed: %d\n", rc);
  }
  if( doPCache ){
    if( nPCache>0 && szPCache>0 ){
      pPCache = malloc( nPCache*(sqlite3_int64)szPCache );
      if( pPCache==0 ) fatal_error("cannot allocate %lld-byte pcache\n",
                                   nPCache*(sqlite3_int64)szPCache);
    }
    rc = sqlite3_config(SQLITE_CONFIG_PAGECACHE, pPCache, szPCache, nPCache);
    if( rc ) fatal_error("pcache configuration failed: %d\n", rc);
  }
  if( nScratch>0 && szScratch>0 ){
    pScratch = malloc( nScratch*(sqlite3_int64)szScratch );
    if( pScratch==0 ) fatal_error("cannot allocate %lld-byte scratch\n",
                                 nScratch*(sqlite3_int64)szScratch);

  set TRACE_OUT {}
  execsql {SELECT * FROM t1}
} {1 2 2 3 2 3}
do_test trace-4.5 {
  set TRACE_OUT
} {{SELECT * FROM t1}}
catch {sqlite3_finalize $STMT}









# Trigger tracing.
#
ifcapable trigger {
  do_test trace-5.1 {
    db eval {
      CREATE TRIGGER r1t1 AFTER UPDATE ON t1 BEGIN

  set TRACE_OUT {}
  execsql {SELECT * FROM t1}
} {1 2 2 3 2 3}
do_test trace-4.5 {
  set TRACE_OUT
} {{SELECT * FROM t1}}
catch {sqlite3_finalize $STMT}

# 3.8.11: Profile output even if the statement is not run to completion.
do_test trace-4.6 {
  set TRACE_OUT {}
  db eval {SELECT * FROM t1} {} {if {$a>=1} break}
  set TRACE_OUT
} {{SELECT * FROM t1}}


# Trigger tracing.
#
ifcapable trigger {
  do_test trace-5.1 {
    db eval {
      CREATE TRIGGER r1t1 AFTER UPDATE ON t1 BEGIN

#
do_catchsql_test 15.1 {
  WITH RECURSIVE
    d(x) AS (VALUES(1) UNION ALL SELECT rowid+1 FROM d WHERE rowid<10)
  SELECT x FROM d;
} {1 {no such column: rowid}}









finish_test

#
do_catchsql_test 15.1 {
  WITH RECURSIVE
    d(x) AS (VALUES(1) UNION ALL SELECT rowid+1 FROM d WHERE rowid<10)
  SELECT x FROM d;
} {1 {no such column: rowid}}

# 2015-07-05:  Do not allow aggregate recursive queries
#
do_catchsql_test 16.1 {
  WITH RECURSIVE
    i(x) AS (VALUES(1) UNION SELECT count(*) FROM i)
  SELECT * FROM i;
} {1 {recursive aggregate queries not supported}}

finish_test

/*
** 2013-06-10
**
** 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.
**
*************************************************************************




*/

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <assert.h>
#include <string.h>

/*
** 2014-07-28
**
** 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.
**
*************************************************************************
**
** This file implements a utility program that will load many disk
** files (all files under a given directory) into a FTS table.  This is
** used for performance testing of FTS3, FTS4, and FTS5.
*/

#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <assert.h>
#include <string.h>