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Overview
Comment:Merge latest trunk into this branch.
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | reuse-schema
Files: files | file ages | folders
SHA3-256: 577d1638362666a8220401d0d0d8bfb3c028ab09e7def1e4bf195db37269c22f
User & Date: dan 2019-02-14 15:56:59
Wiki:reuse-schema
Context
2019-02-14
17:51
Add documentation file doc/shared_schema.md to describe the change on this branch. check-in: a5f8067d user: dan tags: reuse-schema
15:56
Merge latest trunk into this branch. check-in: 577d1638 user: dan tags: reuse-schema
15:47
Add missing comments and fix other code issues in the new functions in callback.c. check-in: 441cabb6 user: dan tags: reuse-schema
15:27
Improved oversized cell detection when updating ptrmap pages in balance_nonroot(). check-in: aa61435a user: drh tags: trunk
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to VERSION.

1
3.27.0
|
1
3.28.0

Changes to configure.

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#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.69 for sqlite 3.27.0.
#
#
# Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
#
#
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.
................................................................................
subdirs=
MFLAGS=
MAKEFLAGS=

# Identity of this package.
PACKAGE_NAME='sqlite'
PACKAGE_TARNAME='sqlite'
PACKAGE_VERSION='3.27.0'
PACKAGE_STRING='sqlite 3.27.0'
PACKAGE_BUGREPORT=''
PACKAGE_URL=''

# Factoring default headers for most tests.
ac_includes_default="\
#include <stdio.h>
#ifdef HAVE_SYS_TYPES_H
................................................................................
#
# Report the --help message.
#
if test "$ac_init_help" = "long"; then
  # Omit some internal or obsolete options to make the list less imposing.
  # This message is too long to be a string in the A/UX 3.1 sh.
  cat <<_ACEOF
\`configure' configures sqlite 3.27.0 to adapt to many kinds of systems.

Usage: $0 [OPTION]... [VAR=VALUE]...

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.
................................................................................
  --build=BUILD     configure for building on BUILD [guessed]
  --host=HOST       cross-compile to build programs to run on HOST [BUILD]
_ACEOF
fi

if test -n "$ac_init_help"; then
  case $ac_init_help in
     short | recursive ) echo "Configuration of sqlite 3.27.0:";;
   esac
  cat <<\_ACEOF

Optional Features:
  --disable-option-checking  ignore unrecognized --enable/--with options
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
................................................................................
    cd "$ac_pwd" || { ac_status=$?; break; }
  done
fi

test -n "$ac_init_help" && exit $ac_status
if $ac_init_version; then
  cat <<\_ACEOF
sqlite configure 3.27.0
generated by GNU Autoconf 2.69

Copyright (C) 2012 Free Software Foundation, Inc.
This configure script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it.
_ACEOF
  exit
................................................................................
  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno

} # ac_fn_c_check_header_mongrel
cat >config.log <<_ACEOF
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.

It was created by sqlite $as_me 3.27.0, which was
generated by GNU Autoconf 2.69.  Invocation command line was

  $ $0 $@

_ACEOF
exec 5>>config.log
{
................................................................................
test $as_write_fail = 0 && chmod +x $CONFIG_STATUS || ac_write_fail=1

cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
# Save the log message, to keep $0 and so on meaningful, and to
# report actual input values of CONFIG_FILES etc. instead of their
# values after options handling.
ac_log="
This file was extended by sqlite $as_me 3.27.0, which was
generated by GNU Autoconf 2.69.  Invocation command line was

  CONFIG_FILES    = $CONFIG_FILES
  CONFIG_HEADERS  = $CONFIG_HEADERS
  CONFIG_LINKS    = $CONFIG_LINKS
  CONFIG_COMMANDS = $CONFIG_COMMANDS
  $ $0 $@
................................................................................

Report bugs to the package provider."

_ACEOF
cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
ac_cs_version="\\
sqlite config.status 3.27.0
configured by $0, generated by GNU Autoconf 2.69,
  with options \\"\$ac_cs_config\\"

Copyright (C) 2012 Free Software Foundation, Inc.
This config.status script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it."



|







 







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#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.69 for sqlite 3.28.0.
#
#
# Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
#
#
# This configure script is free software; the Free Software Foundation
# gives unlimited permission to copy, distribute and modify it.
................................................................................
subdirs=
MFLAGS=
MAKEFLAGS=

# Identity of this package.
PACKAGE_NAME='sqlite'
PACKAGE_TARNAME='sqlite'
PACKAGE_VERSION='3.28.0'
PACKAGE_STRING='sqlite 3.28.0'
PACKAGE_BUGREPORT=''
PACKAGE_URL=''

# Factoring default headers for most tests.
ac_includes_default="\
#include <stdio.h>
#ifdef HAVE_SYS_TYPES_H
................................................................................
#
# Report the --help message.
#
if test "$ac_init_help" = "long"; then
  # Omit some internal or obsolete options to make the list less imposing.
  # This message is too long to be a string in the A/UX 3.1 sh.
  cat <<_ACEOF
\`configure' configures sqlite 3.28.0 to adapt to many kinds of systems.

Usage: $0 [OPTION]... [VAR=VALUE]...

To assign environment variables (e.g., CC, CFLAGS...), specify them as
VAR=VALUE.  See below for descriptions of some of the useful variables.

Defaults for the options are specified in brackets.
................................................................................
  --build=BUILD     configure for building on BUILD [guessed]
  --host=HOST       cross-compile to build programs to run on HOST [BUILD]
_ACEOF
fi

if test -n "$ac_init_help"; then
  case $ac_init_help in
     short | recursive ) echo "Configuration of sqlite 3.28.0:";;
   esac
  cat <<\_ACEOF

Optional Features:
  --disable-option-checking  ignore unrecognized --enable/--with options
  --disable-FEATURE       do not include FEATURE (same as --enable-FEATURE=no)
  --enable-FEATURE[=ARG]  include FEATURE [ARG=yes]
................................................................................
    cd "$ac_pwd" || { ac_status=$?; break; }
  done
fi

test -n "$ac_init_help" && exit $ac_status
if $ac_init_version; then
  cat <<\_ACEOF
sqlite configure 3.28.0
generated by GNU Autoconf 2.69

Copyright (C) 2012 Free Software Foundation, Inc.
This configure script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it.
_ACEOF
  exit
................................................................................
  eval $as_lineno_stack; ${as_lineno_stack:+:} unset as_lineno

} # ac_fn_c_check_header_mongrel
cat >config.log <<_ACEOF
This file contains any messages produced by compilers while
running configure, to aid debugging if configure makes a mistake.

It was created by sqlite $as_me 3.28.0, which was
generated by GNU Autoconf 2.69.  Invocation command line was

  $ $0 $@

_ACEOF
exec 5>>config.log
{
................................................................................
test $as_write_fail = 0 && chmod +x $CONFIG_STATUS || ac_write_fail=1

cat >>$CONFIG_STATUS <<\_ACEOF || ac_write_fail=1
# Save the log message, to keep $0 and so on meaningful, and to
# report actual input values of CONFIG_FILES etc. instead of their
# values after options handling.
ac_log="
This file was extended by sqlite $as_me 3.28.0, which was
generated by GNU Autoconf 2.69.  Invocation command line was

  CONFIG_FILES    = $CONFIG_FILES
  CONFIG_HEADERS  = $CONFIG_HEADERS
  CONFIG_LINKS    = $CONFIG_LINKS
  CONFIG_COMMANDS = $CONFIG_COMMANDS
  $ $0 $@
................................................................................

Report bugs to the package provider."

_ACEOF
cat >>$CONFIG_STATUS <<_ACEOF || ac_write_fail=1
ac_cs_config="`$as_echo "$ac_configure_args" | sed 's/^ //; s/[\\""\`\$]/\\\\&/g'`"
ac_cs_version="\\
sqlite config.status 3.28.0
configured by $0, generated by GNU Autoconf 2.69,
  with options \\"\$ac_cs_config\\"

Copyright (C) 2012 Free Software Foundation, Inc.
This config.status script is free software; the Free Software Foundation
gives unlimited permission to copy, distribute and modify it."

Changes to ext/misc/vfsstat.c.

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/*
** This routine is an sqlite3_auto_extension() callback, invoked to register
** the vfsstat virtual table for all new database connections.
*/
static int vstatRegister(
  sqlite3 *db,
  const char **pzErrMsg,
  const struct sqlite3_api_routines *pThunk
){
  return sqlite3_create_module(db, "vfsstat", &VfsStatModule, 0);
}

#ifdef _WIN32
__declspec(dllexport)
#endif
................................................................................
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  vstat_vfs.pVfs = sqlite3_vfs_find(0);
  vstat_vfs.base.szOsFile = sizeof(VStatFile) + vstat_vfs.pVfs->szOsFile;
  rc = sqlite3_vfs_register(&vstat_vfs.base, 1);
  if( rc==SQLITE_OK ){


    rc = sqlite3_auto_extension(vstatRegister);

  }
  if( rc==SQLITE_OK ) rc = SQLITE_OK_LOAD_PERMANENTLY;
  return rc;
}







|
|







 







>
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/*
** This routine is an sqlite3_auto_extension() callback, invoked to register
** the vfsstat virtual table for all new database connections.
*/
static int vstatRegister(
  sqlite3 *db,
  char **pzErrMsg,
  const sqlite3_api_routines *pThunk
){
  return sqlite3_create_module(db, "vfsstat", &VfsStatModule, 0);
}

#ifdef _WIN32
__declspec(dllexport)
#endif
................................................................................
){
  int rc = SQLITE_OK;
  SQLITE_EXTENSION_INIT2(pApi);
  vstat_vfs.pVfs = sqlite3_vfs_find(0);
  vstat_vfs.base.szOsFile = sizeof(VStatFile) + vstat_vfs.pVfs->szOsFile;
  rc = sqlite3_vfs_register(&vstat_vfs.base, 1);
  if( rc==SQLITE_OK ){
    rc = vstatRegister(db, pzErrMsg, pApi);
    if( rc==SQLITE_OK ){
      rc = sqlite3_auto_extension(vstatRegister);
    }
  }
  if( rc==SQLITE_OK ) rc = SQLITE_OK_LOAD_PERMANENTLY;
  return rc;
}

Changes to src/btree.c.

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  ** or fewer fragmented bytes. In this case it is faster to move the
  ** two (or one) blocks of cells using memmove() and add the required
  ** offsets to each pointer in the cell-pointer array than it is to 
  ** reconstruct the entire page.  */
  if( (int)data[hdr+7]<=nMaxFrag ){
    int iFree = get2byte(&data[hdr+1]);

    /* If the initial freeblock offset were out of bounds, that would
    ** have been detected by btreeInitPage() when it was computing the
    ** number of free bytes on the page. */
    assert( iFree<=usableSize-4 );
    if( iFree ){
      int iFree2 = get2byte(&data[iFree]);
      if( iFree2>usableSize-4 ) return SQLITE_CORRUPT_PAGE(pPage);
      if( 0==iFree2 || (data[iFree2]==0 && data[iFree2+1]==0) ){
        u8 *pEnd = &data[cellOffset + nCell*2];
................................................................................
      src = temp;
    }
    memcpy(&data[cbrk], &src[pc], size);
  }
  data[hdr+7] = 0;

 defragment_out:

  if( data[hdr+7]+cbrk-iCellFirst!=pPage->nFree ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  assert( cbrk>=iCellFirst );
  put2byte(&data[hdr+5], cbrk);
  data[hdr+1] = 0;
  data[hdr+2] = 0;
................................................................................
    if( top==0 && pPage->pBt->usableSize==65536 ){
      top = 65536;
    }else{
      return SQLITE_CORRUPT_PAGE(pPage);
    }
  }

  /* If there is enough space between gap and top for one more cell pointer
  ** array entry offset, and if the freelist is not empty, then search the
  ** freelist looking for a free slot big enough to satisfy the request.
  */
  testcase( gap+2==top );
  testcase( gap+1==top );
  testcase( gap==top );
  if( (data[hdr+2] || data[hdr+1]) && gap+2<=top ){
    u8 *pSpace = pageFindSlot(pPage, nByte, &rc);
    if( pSpace ){
................................................................................

  /* The request could not be fulfilled using a freelist slot.  Check
  ** to see if defragmentation is necessary.
  */
  testcase( gap+2+nByte==top );
  if( gap+2+nByte>top ){
    assert( pPage->nCell>0 || CORRUPT_DB );

    rc = defragmentPage(pPage, MIN(4, pPage->nFree - (2+nByte)));
    if( rc ) return rc;
    top = get2byteNotZero(&data[hdr+5]);
    assert( gap+2+nByte<=top );
  }


  /* Allocate memory from the gap in between the cell pointer array
  ** and the cell content area.  The btreeInitPage() call has already
  ** validated the freelist.  Given that the freelist is valid, there
  ** is no way that the allocation can extend off the end of the page.
  ** The assert() below verifies the previous sentence.
  */
  top -= nByte;
  put2byte(&data[hdr+5], top);
  assert( top+nByte <= (int)pPage->pBt->usableSize );
................................................................................
/*
** Return a section of the pPage->aData to the freelist.
** The first byte of the new free block is pPage->aData[iStart]
** and the size of the block is iSize bytes.
**
** Adjacent freeblocks are coalesced.
**
** Note that even though the freeblock list was checked by btreeInitPage(),
** that routine will not detect overlap between cells or freeblocks.  Nor
** does it detect cells or freeblocks that encrouch into the reserved bytes
** at the end of the page.  So do additional corruption checks inside this
** routine and return SQLITE_CORRUPT if any problems are found.
*/
static int freeSpace(MemPage *pPage, u16 iStart, u16 iSize){
  u16 iPtr;                             /* Address of ptr to next freeblock */
................................................................................
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  pPage->max1bytePayload = pBt->max1bytePayload;
  return SQLITE_OK;
}

/*
** Initialize the auxiliary information for a disk block.
**
** Return SQLITE_OK on success.  If we see that the page does
** not contain a well-formed database page, then return 
** SQLITE_CORRUPT.  Note that a return of SQLITE_OK does not
** guarantee that the page is well-formed.  It only shows that
** we failed to detect any corruption.
*/
static int btreeInitPage(MemPage *pPage){

  int pc;            /* Address of a freeblock within pPage->aData[] */
  u8 hdr;            /* Offset to beginning of page header */
  u8 *data;          /* Equal to pPage->aData */
  BtShared *pBt;        /* The main btree structure */
  int usableSize;    /* Amount of usable space on each page */
  u16 cellOffset;    /* Offset from start of page to first cell pointer */
  int nFree;         /* Number of unused bytes on the page */
  int top;           /* First byte of the cell content area */
  int iCellFirst;    /* First allowable cell or freeblock offset */
  int iCellLast;     /* Last possible cell or freeblock offset */

  assert( pPage->pBt!=0 );
  assert( pPage->pBt->db!=0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );
  assert( pPage->isInit==0 );


  pBt = pPage->pBt;
  hdr = pPage->hdrOffset;
  data = pPage->aData;
  /* EVIDENCE-OF: R-28594-02890 The one-byte flag at offset 0 indicating
  ** the b-tree page type. */
  if( decodeFlags(pPage, data[hdr]) ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
  pPage->maskPage = (u16)(pBt->pageSize - 1);
  pPage->nOverflow = 0;
  usableSize = pBt->usableSize;
  pPage->cellOffset = cellOffset = hdr + 8 + pPage->childPtrSize;
  pPage->aDataEnd = &data[usableSize];
  pPage->aCellIdx = &data[cellOffset];
  pPage->aDataOfst = &data[pPage->childPtrSize];
  /* EVIDENCE-OF: R-58015-48175 The two-byte integer at offset 5 designates
  ** the start of the cell content area. A zero value for this integer is
  ** interpreted as 65536. */
  top = get2byteNotZero(&data[hdr+5]);
  /* EVIDENCE-OF: R-37002-32774 The two-byte integer at offset 3 gives the
  ** number of cells on the page. */
  pPage->nCell = get2byte(&data[hdr+3]);
  if( pPage->nCell>MX_CELL(pBt) ){
    /* To many cells for a single page.  The page must be corrupt */
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  testcase( pPage->nCell==MX_CELL(pBt) );
  /* EVIDENCE-OF: R-24089-57979 If a page contains no cells (which is only
  ** possible for a root page of a table that contains no rows) then the
  ** offset to the cell content area will equal the page size minus the
  ** bytes of reserved space. */
  assert( pPage->nCell>0 || top==usableSize || CORRUPT_DB );

  /* A malformed database page might cause us to read past the end
  ** of page when parsing a cell.  
  **
  ** The following block of code checks early to see if a cell extends
  ** past the end of a page boundary and causes SQLITE_CORRUPT to be 
  ** returned if it does.
  */
  iCellFirst = cellOffset + 2*pPage->nCell;

  iCellLast = usableSize - 4;
  if( pBt->db->flags & SQLITE_CellSizeCk ){
    int i;            /* Index into the cell pointer array */
    int sz;           /* Size of a cell */

    if( !pPage->leaf ) iCellLast--;
    for(i=0; i<pPage->nCell; i++){
      pc = get2byteAligned(&data[cellOffset+i*2]);
      testcase( pc==iCellFirst );
      testcase( pc==iCellLast );
      if( pc<iCellFirst || pc>iCellLast ){
        return SQLITE_CORRUPT_PAGE(pPage);
      }
      sz = pPage->xCellSize(pPage, &data[pc]);
      testcase( pc+sz==usableSize );
      if( pc+sz>usableSize ){
        return SQLITE_CORRUPT_PAGE(pPage);
      }
    }
    if( !pPage->leaf ) iCellLast++;
  }  

  /* Compute the total free space on the page
  ** EVIDENCE-OF: R-23588-34450 The two-byte integer at offset 1 gives the
  ** start of the first freeblock on the page, or is zero if there are no
  ** freeblocks. */
  pc = get2byte(&data[hdr+1]);
  nFree = data[hdr+7] + top;  /* Init nFree to non-freeblock free space */
................................................................................
  ** serves to verify that the offset to the start of the cell-content
  ** area, according to the page header, lies within the page.
  */
  if( nFree>usableSize ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  pPage->nFree = (u16)(nFree - iCellFirst);


























































































  pPage->isInit = 1;



  return SQLITE_OK;
}

/*
** Set up a raw page so that it looks like a database page holding
** no entries.
*/
................................................................................
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( pCur==0 || ppPage==&pCur->pPage );
  assert( pCur==0 || bReadOnly==pCur->curPagerFlags );
  assert( pCur==0 || pCur->iPage>0 );

  if( pgno>btreePagecount(pBt) ){
    rc = SQLITE_CORRUPT_BKPT;
    goto getAndInitPage_error;
  }
  rc = sqlite3PagerGet(pBt->pPager, pgno, (DbPage**)&pDbPage, bReadOnly);
  if( rc ){
    goto getAndInitPage_error;
  }
  *ppPage = (MemPage*)sqlite3PagerGetExtra(pDbPage);
  if( (*ppPage)->isInit==0 ){
    btreePageFromDbPage(pDbPage, pgno, pBt);
    rc = btreeInitPage(*ppPage);
    if( rc!=SQLITE_OK ){
      releasePage(*ppPage);
      goto getAndInitPage_error;
    }
  }
  assert( (*ppPage)->pgno==pgno );
  assert( (*ppPage)->aData==sqlite3PagerGetData(pDbPage) );

  /* If obtaining a child page for a cursor, we must verify that the page is
  ** compatible with the root page. */
  if( pCur && ((*ppPage)->nCell<1 || (*ppPage)->intKey!=pCur->curIntKey) ){
    rc = SQLITE_CORRUPT_PGNO(pgno);
    releasePage(*ppPage);
    goto getAndInitPage_error;
  }
  return SQLITE_OK;

getAndInitPage_error:


  if( pCur ){
    pCur->iPage--;
    pCur->pPage = pCur->apPage[pCur->iPage];
  }
  testcase( pgno==0 );
  assert( pgno!=0 || rc==SQLITE_CORRUPT );
  return rc;
................................................................................
  int hdr;        /* Beginning of the header.  0 most pages.  100 page 1 */

  if( *pRC ) return;
  assert( idx>=0 && idx<pPage->nCell );
  assert( CORRUPT_DB || sz==cellSize(pPage, idx) );
  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );

  data = pPage->aData;
  ptr = &pPage->aCellIdx[2*idx];
  pc = get2byte(ptr);
  hdr = pPage->hdrOffset;
  testcase( pc==get2byte(&data[hdr+5]) );
  testcase( pc+sz==pPage->pBt->usableSize );
  if( pc+sz > pPage->pBt->usableSize ){
................................................................................
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  /* The cell should normally be sized correctly.  However, when moving a
  ** malformed cell from a leaf page to an interior page, if the cell size
  ** wanted to be less than 4 but got rounded up to 4 on the leaf, then size
  ** might be less than 8 (leaf-size + pointer) on the interior node.  Hence
  ** the term after the || in the following assert(). */
  assert( sz==pPage->xCellSize(pPage, pCell) || (sz==8 && iChild>0) );

  if( pPage->nOverflow || sz+2>pPage->nFree ){
    if( pTemp ){
      memcpy(pTemp, pCell, sz);
      pCell = pTemp;
    }
    if( iChild ){
      put4byte(pCell, iChild);
................................................................................
**    ixNx[3] = Number of cells in Child-1 and Child-2 + both divider cells
**    ixNx[4] = Total number of cells.
**
** For a table-btree, the concept is similar, except only apEnd[0]..apEnd[2]
** are used and they point to the leaf pages only, and the ixNx value are:
**
**    ixNx[0] = Number of cells in Child-1.
**    ixNx[1] = Number of cells in Child-1 and Child-2 + 1 for 1st divider.
**    ixNx[2] = Number of cells in Child-1 and Child-2 + both divider cells





*/
typedef struct CellArray CellArray;
struct CellArray {
  int nCell;              /* Number of cells in apCell[] */
  MemPage *pRef;          /* Reference page */
  u8 **apCell;            /* All cells begin balanced */
  u16 *szCell;            /* Local size of all cells in apCell[] */
................................................................................
  MemPage *pNew;                       /* Newly allocated page */
  int rc;                              /* Return Code */
  Pgno pgnoNew;                        /* Page number of pNew */

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( sqlite3PagerIswriteable(pParent->pDbPage) );
  assert( pPage->nOverflow==1 );

  if( pPage->nCell==0 ) return SQLITE_CORRUPT_BKPT;  /* dbfuzz001.test */



  /* Allocate a new page. This page will become the right-sibling of 
  ** pPage. Make the parent page writable, so that the new divider cell
  ** may be inserted. If both these operations are successful, proceed.
  */
  rc = allocateBtreePage(pBt, &pNew, &pgnoNew, 0, 0);

................................................................................
    /* Reinitialize page pTo so that the contents of the MemPage structure
    ** match the new data. The initialization of pTo can actually fail under
    ** fairly obscure circumstances, even though it is a copy of initialized 
    ** page pFrom.
    */
    pTo->isInit = 0;
    rc = btreeInitPage(pTo);

    if( rc!=SQLITE_OK ){
      *pRC = rc;
      return;
    }
  
    /* If this is an auto-vacuum database, update the pointer-map entries
    ** for any b-tree or overflow pages that pTo now contains the pointers to.
................................................................................
  */
  assert( pParent->nOverflow==0 || pParent->nOverflow==1 );
  assert( pParent->nOverflow==0 || pParent->aiOvfl[0]==iParentIdx );

  if( !aOvflSpace ){
    return SQLITE_NOMEM_BKPT;
  }


  /* Find the sibling pages to balance. Also locate the cells in pParent 
  ** that divide the siblings. An attempt is made to find NN siblings on 
  ** either side of pPage. More siblings are taken from one side, however, 
  ** if there are fewer than NN siblings on the other side. If pParent
  ** has NB or fewer children then all children of pParent are taken.  
  **
................................................................................
  }
  pgno = get4byte(pRight);
  while( 1 ){
    rc = getAndInitPage(pBt, pgno, &apOld[i], 0, 0);
    if( rc ){
      memset(apOld, 0, (i+1)*sizeof(MemPage*));
      goto balance_cleanup;







    }
    nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
    if( (i--)==0 ) break;

    if( pParent->nOverflow && i+nxDiv==pParent->aiOvfl[0] ){
      apDiv[i] = pParent->apOvfl[0];
      pgno = get4byte(apDiv[i]);
................................................................................
  ** 
  */
  usableSpace = pBt->usableSize - 12 + leafCorrection;
  for(i=k=0; i<nOld; i++, k++){
    MemPage *p = apOld[i];
    b.apEnd[k] = p->aDataEnd;
    b.ixNx[k] = cntOld[i];



    if( !leafData ){
      k++;
      b.apEnd[k] = pParent->aDataEnd;
      b.ixNx[k] = cntOld[i]+1;
    }

    szNew[i] = usableSpace - p->nFree;
    for(j=0; j<p->nOverflow; j++){
      szNew[i] += 2 + p->xCellSize(p, p->apOvfl[j]);
    }
    cntNew[i] = cntOld[i];
  }
  k = nOld;
................................................................................
  ** associated with the right-child of each sibling may also need to be 
  ** updated. This happens below, after the sibling pages have been 
  ** populated, not here.
  */
  if( ISAUTOVACUUM ){
    MemPage *pOld;
    MemPage *pNew = pOld = apNew[0];
    u8 *aOld = pNew->aData;
    int cntOldNext = pNew->nCell + pNew->nOverflow;
    int usableSize = pBt->usableSize;
    int iNew = 0;
    int iOld = 0;

    for(i=0; i<b.nCell; i++){
      u8 *pCell = b.apCell[i];
      if( i==cntOldNext ){


        pOld = (++iOld)<nNew ? apNew[iOld] : apOld[iOld];
        cntOldNext += pOld->nCell + pOld->nOverflow + !leafData;
        aOld = pOld->aData;
      }
      if( i==cntNew[iNew] ){
        pNew = apNew[++iNew];
        if( !leafData ) continue;
      }

      /* Cell pCell is destined for new sibling page pNew. Originally, it
................................................................................
      ** was either part of sibling page iOld (possibly an overflow cell), 
      ** or else the divider cell to the left of sibling page iOld. So,
      ** if sibling page iOld had the same page number as pNew, and if
      ** pCell really was a part of sibling page iOld (not a divider or
      ** overflow cell), we can skip updating the pointer map entries.  */
      if( iOld>=nNew
       || pNew->pgno!=aPgno[iOld]
       || !SQLITE_WITHIN(pCell,aOld,&aOld[usableSize])
      ){
        if( !leafCorrection ){
          ptrmapPut(pBt, get4byte(pCell), PTRMAP_BTREE, pNew->pgno, &rc);
        }
        if( cachedCellSize(&b,i)>pNew->minLocal ){
          ptrmapPutOvflPtr(pNew, pOld, pCell, &rc);
        }
................................................................................
  VVA_ONLY( int balance_quick_called = 0 );
  VVA_ONLY( int balance_deeper_called = 0 );

  do {
    int iPage = pCur->iPage;
    MemPage *pPage = pCur->pPage;


    if( iPage==0 ){
      if( pPage->nOverflow ){
        /* The root page of the b-tree is overfull. In this case call the
        ** balance_deeper() function to create a new child for the root-page
        ** and copy the current contents of the root-page to it. The
        ** next iteration of the do-loop will balance the child page.
        */ 
................................................................................
    }else if( pPage->nOverflow==0 && pPage->nFree<=nMin ){
      break;
    }else{
      MemPage * const pParent = pCur->apPage[iPage-1];
      int const iIdx = pCur->aiIdx[iPage-1];

      rc = sqlite3PagerWrite(pParent->pDbPage);



      if( rc==SQLITE_OK ){
#ifndef SQLITE_OMIT_QUICKBALANCE
        if( pPage->intKeyLeaf
         && pPage->nOverflow==1
         && pPage->aiOvfl[0]==pPage->nCell
         && pParent->pgno!=1
         && pParent->nCell==iIdx
................................................................................

  }
  assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );

  pPage = pCur->pPage;
  assert( pPage->intKey || pX->nKey>=0 );
  assert( pPage->leaf || !pPage->intKey );





  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, pX->nKey, pX->nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  newCell = pBt->pTmpSpace;
  assert( newCell!=0 );
................................................................................
  assert( pCur->eState==CURSOR_VALID );
  assert( (flags & ~(BTREE_SAVEPOSITION | BTREE_AUXDELETE))==0 );

  iCellDepth = pCur->iPage;
  iCellIdx = pCur->ix;
  pPage = pCur->pPage;
  pCell = findCell(pPage, iCellIdx);


  /* If the bPreserve flag is set to true, then the cursor position must
  ** be preserved following this delete operation. If the current delete
  ** will cause a b-tree rebalance, then this is done by saving the cursor
  ** key and leaving the cursor in CURSOR_REQUIRESEEK state before 
  ** returning. 
  **
................................................................................
  ** node to replace the deleted cell.  */
  if( !pPage->leaf ){
    MemPage *pLeaf = pCur->pPage;
    int nCell;
    Pgno n;
    unsigned char *pTmp;





    if( iCellDepth<pCur->iPage-1 ){
      n = pCur->apPage[iCellDepth+1]->pgno;
    }else{
      n = pCur->pPage->pgno;
    }
    pCell = findCell(pLeaf, pLeaf->nCell-1);
    if( pCell<&pLeaf->aData[4] ) return SQLITE_CORRUPT_BKPT;
................................................................................
  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;
  }





  data = pPage->aData;
  hdr = pPage->hdrOffset;

  /* Set up for cell analysis */
  pCheck->zPfx = "On tree page %d cell %d: ";
  contentOffset = get2byteNotZero(&data[hdr+5]);
  assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */
................................................................................
    ** EVIDENCE-OF: R-20690-50594 The second field of the b-tree page header
    ** is the offset of the first freeblock, or zero if there are no
    ** freeblocks on the page. 
    */
    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







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....
7225
7226
7227
7228
7229
7230
7231
7232
7233
7234
7235
7236
7237
7238
7239
7240
7241
7242
....
7398
7399
7400
7401
7402
7403
7404
7405
7406
7407
7408
7409
7410
7411
7412
....
7507
7508
7509
7510
7511
7512
7513
7514
7515
7516
7517
7518
7519
7520
7521
....
7546
7547
7548
7549
7550
7551
7552
7553
7554
7555
7556
7557
7558
7559
7560
7561
7562
7563
7564
7565
7566
....
7748
7749
7750
7751
7752
7753
7754
7755
7756
7757
7758
7759
7760
7761
7762
7763
7764
7765
7766
7767
7768
7769
7770
....
7982
7983
7984
7985
7986
7987
7988

7989

7990
7991
7992
7993
7994
7995
7996
7997
7998
7999

8000
8001
8002
8003
8004
8005
8006
....
8007
8008
8009
8010
8011
8012
8013
8014
8015
8016
8017
8018
8019
8020
8021
....
8299
8300
8301
8302
8303
8304
8305
8306
8307
8308
8309
8310
8311
8312
8313
....
8328
8329
8330
8331
8332
8333
8334
8335
8336
8337
8338
8339
8340
8341
8342
8343
8344
....
8677
8678
8679
8680
8681
8682
8683
8684
8685
8686
8687
8688
8689
8690
8691
8692
8693
8694
....
8831
8832
8833
8834
8835
8836
8837
8838
8839
8840
8841
8842
8843
8844
8845
....
8902
8903
8904
8905
8906
8907
8908
8909
8910
8911
8912
8913
8914
8915
8916
8917
8918
8919
....
9797
9798
9799
9800
9801
9802
9803
9804
9805
9806
9807
9808
9809
9810
9811
9812
9813
9814
9815
....
9934
9935
9936
9937
9938
9939
9940
9941
9942
9943
9944
9945
9946
9947
9948
9949
9950
9951
9952
9953
9954
9955
9956
9957
9958
9959
9960
  ** or fewer fragmented bytes. In this case it is faster to move the
  ** two (or one) blocks of cells using memmove() and add the required
  ** offsets to each pointer in the cell-pointer array than it is to 
  ** reconstruct the entire page.  */
  if( (int)data[hdr+7]<=nMaxFrag ){
    int iFree = get2byte(&data[hdr+1]);

    /* If the initial freeblock offset were out of bounds, that would have
    ** been detected by btreeComputeFreeSpace() when it was computing the
    ** number of free bytes on the page. */
    assert( iFree<=usableSize-4 );
    if( iFree ){
      int iFree2 = get2byte(&data[iFree]);
      if( iFree2>usableSize-4 ) return SQLITE_CORRUPT_PAGE(pPage);
      if( 0==iFree2 || (data[iFree2]==0 && data[iFree2+1]==0) ){
        u8 *pEnd = &data[cellOffset + nCell*2];
................................................................................
      src = temp;
    }
    memcpy(&data[cbrk], &src[pc], size);
  }
  data[hdr+7] = 0;

 defragment_out:
  assert( pPage->nFree>=0 );
  if( data[hdr+7]+cbrk-iCellFirst!=pPage->nFree ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  assert( cbrk>=iCellFirst );
  put2byte(&data[hdr+5], cbrk);
  data[hdr+1] = 0;
  data[hdr+2] = 0;
................................................................................
    if( top==0 && pPage->pBt->usableSize==65536 ){
      top = 65536;
    }else{
      return SQLITE_CORRUPT_PAGE(pPage);
    }
  }

  /* If there is enough space between gap and top for one more cell pointer,
  ** and if the freelist is not empty, then search the
  ** freelist looking for a slot big enough to satisfy the request.
  */
  testcase( gap+2==top );
  testcase( gap+1==top );
  testcase( gap==top );
  if( (data[hdr+2] || data[hdr+1]) && gap+2<=top ){
    u8 *pSpace = pageFindSlot(pPage, nByte, &rc);
    if( pSpace ){
................................................................................

  /* The request could not be fulfilled using a freelist slot.  Check
  ** to see if defragmentation is necessary.
  */
  testcase( gap+2+nByte==top );
  if( gap+2+nByte>top ){
    assert( pPage->nCell>0 || CORRUPT_DB );
    assert( pPage->nFree>=0 );
    rc = defragmentPage(pPage, MIN(4, pPage->nFree - (2+nByte)));
    if( rc ) return rc;
    top = get2byteNotZero(&data[hdr+5]);
    assert( gap+2+nByte<=top );
  }


  /* Allocate memory from the gap in between the cell pointer array
  ** and the cell content area.  The btreeComputeFreeSpace() call has already
  ** validated the freelist.  Given that the freelist is valid, there
  ** is no way that the allocation can extend off the end of the page.
  ** The assert() below verifies the previous sentence.
  */
  top -= nByte;
  put2byte(&data[hdr+5], top);
  assert( top+nByte <= (int)pPage->pBt->usableSize );
................................................................................
/*
** Return a section of the pPage->aData to the freelist.
** The first byte of the new free block is pPage->aData[iStart]
** and the size of the block is iSize bytes.
**
** Adjacent freeblocks are coalesced.
**
** Even though the freeblock list was checked by btreeComputeFreeSpace(),
** that routine will not detect overlap between cells or freeblocks.  Nor
** does it detect cells or freeblocks that encrouch into the reserved bytes
** at the end of the page.  So do additional corruption checks inside this
** routine and return SQLITE_CORRUPT if any problems are found.
*/
static int freeSpace(MemPage *pPage, u16 iStart, u16 iSize){
  u16 iPtr;                             /* Address of ptr to next freeblock */
................................................................................
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  pPage->max1bytePayload = pBt->max1bytePayload;
  return SQLITE_OK;
}

/*
** Compute the amount of freespace on the page.  In other words, fill
** in the pPage->nFree field.





*/

static int btreeComputeFreeSpace(MemPage *pPage){
  int pc;            /* Address of a freeblock within pPage->aData[] */
  u8 hdr;            /* Offset to beginning of page header */
  u8 *data;          /* Equal to pPage->aData */

  int usableSize;    /* Amount of usable space on each page */

  int nFree;         /* Number of unused bytes on the page */
  int top;           /* First byte of the cell content area */
  int iCellFirst;    /* First allowable cell or freeblock offset */
  int iCellLast;     /* Last possible cell or freeblock offset */

  assert( pPage->pBt!=0 );
  assert( pPage->pBt->db!=0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );
  assert( pPage->isInit==1 );
  assert( pPage->nFree<0 );

  usableSize = pPage->pBt->usableSize;
  hdr = pPage->hdrOffset;
  data = pPage->aData;













  /* EVIDENCE-OF: R-58015-48175 The two-byte integer at offset 5 designates
  ** the start of the cell content area. A zero value for this integer is
  ** interpreted as 65536. */
  top = get2byteNotZero(&data[hdr+5]);






















  iCellFirst = hdr + 8 + pPage->childPtrSize + 2*pPage->nCell;
  iCellLast = usableSize - 4;





















  /* Compute the total free space on the page
  ** EVIDENCE-OF: R-23588-34450 The two-byte integer at offset 1 gives the
  ** start of the first freeblock on the page, or is zero if there are no
  ** freeblocks. */
  pc = get2byte(&data[hdr+1]);
  nFree = data[hdr+7] + top;  /* Init nFree to non-freeblock free space */
................................................................................
  ** serves to verify that the offset to the start of the cell-content
  ** area, according to the page header, lies within the page.
  */
  if( nFree>usableSize ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  pPage->nFree = (u16)(nFree - iCellFirst);
  return SQLITE_OK;
}

/*
** Do additional sanity check after btreeInitPage() if
** PRAGMA cell_size_check=ON 
*/
static SQLITE_NOINLINE int btreeCellSizeCheck(MemPage *pPage){
  int iCellFirst;    /* First allowable cell or freeblock offset */
  int iCellLast;     /* Last possible cell or freeblock offset */
  int i;             /* Index into the cell pointer array */
  int sz;            /* Size of a cell */
  int pc;            /* Address of a freeblock within pPage->aData[] */
  u8 *data;          /* Equal to pPage->aData */
  int usableSize;    /* Maximum usable space on the page */
  int cellOffset;    /* Start of cell content area */

  iCellFirst = pPage->cellOffset + 2*pPage->nCell;
  usableSize = pPage->pBt->usableSize;
  iCellLast = usableSize - 4;
  data = pPage->aData;
  cellOffset = pPage->cellOffset;
  if( !pPage->leaf ) iCellLast--;
  for(i=0; i<pPage->nCell; i++){
    pc = get2byteAligned(&data[cellOffset+i*2]);
    testcase( pc==iCellFirst );
    testcase( pc==iCellLast );
    if( pc<iCellFirst || pc>iCellLast ){
      return SQLITE_CORRUPT_PAGE(pPage);
    }
    sz = pPage->xCellSize(pPage, &data[pc]);
    testcase( pc+sz==usableSize );
    if( pc+sz>usableSize ){
      return SQLITE_CORRUPT_PAGE(pPage);
    }
  }
  return SQLITE_OK;
}

/*
** Initialize the auxiliary information for a disk block.
**
** Return SQLITE_OK on success.  If we see that the page does
** not contain a well-formed database page, then return 
** SQLITE_CORRUPT.  Note that a return of SQLITE_OK does not
** guarantee that the page is well-formed.  It only shows that
** we failed to detect any corruption.
*/
static int btreeInitPage(MemPage *pPage){
  u8 *data;          /* Equal to pPage->aData */
  BtShared *pBt;        /* The main btree structure */

  assert( pPage->pBt!=0 );
  assert( pPage->pBt->db!=0 );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->pgno==sqlite3PagerPagenumber(pPage->pDbPage) );
  assert( pPage == sqlite3PagerGetExtra(pPage->pDbPage) );
  assert( pPage->aData == sqlite3PagerGetData(pPage->pDbPage) );
  assert( pPage->isInit==0 );

  pBt = pPage->pBt;
  data = pPage->aData + pPage->hdrOffset;
  /* EVIDENCE-OF: R-28594-02890 The one-byte flag at offset 0 indicating
  ** the b-tree page type. */
  if( decodeFlags(pPage, data[0]) ){
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  assert( pBt->pageSize>=512 && pBt->pageSize<=65536 );
  pPage->maskPage = (u16)(pBt->pageSize - 1);
  pPage->nOverflow = 0;
  pPage->cellOffset = pPage->hdrOffset + 8 + pPage->childPtrSize;
  pPage->aCellIdx = data + pPage->childPtrSize + 8;
  pPage->aDataEnd = pPage->aData + pBt->usableSize;
  pPage->aDataOfst = pPage->aData + pPage->childPtrSize;
  /* EVIDENCE-OF: R-37002-32774 The two-byte integer at offset 3 gives the
  ** number of cells on the page. */
  pPage->nCell = get2byte(&data[3]);
  if( pPage->nCell>MX_CELL(pBt) ){
    /* To many cells for a single page.  The page must be corrupt */
    return SQLITE_CORRUPT_PAGE(pPage);
  }
  testcase( pPage->nCell==MX_CELL(pBt) );
  /* EVIDENCE-OF: R-24089-57979 If a page contains no cells (which is only
  ** possible for a root page of a table that contains no rows) then the
  ** offset to the cell content area will equal the page size minus the
  ** bytes of reserved space. */
  assert( pPage->nCell>0
       || get2byteNotZero(&data[5])==pBt->usableSize
       || CORRUPT_DB );
  pPage->nFree = -1;  /* Indicate that this value is yet uncomputed */
  pPage->isInit = 1;
  if( pBt->db->flags & SQLITE_CellSizeCk ){
    return btreeCellSizeCheck(pPage);
  }
  return SQLITE_OK;
}

/*
** Set up a raw page so that it looks like a database page holding
** no entries.
*/
................................................................................
  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( pCur==0 || ppPage==&pCur->pPage );
  assert( pCur==0 || bReadOnly==pCur->curPagerFlags );
  assert( pCur==0 || pCur->iPage>0 );

  if( pgno>btreePagecount(pBt) ){
    rc = SQLITE_CORRUPT_BKPT;
    goto getAndInitPage_error1;
  }
  rc = sqlite3PagerGet(pBt->pPager, pgno, (DbPage**)&pDbPage, bReadOnly);
  if( rc ){
    goto getAndInitPage_error1;
  }
  *ppPage = (MemPage*)sqlite3PagerGetExtra(pDbPage);
  if( (*ppPage)->isInit==0 ){
    btreePageFromDbPage(pDbPage, pgno, pBt);
    rc = btreeInitPage(*ppPage);
    if( rc!=SQLITE_OK ){

      goto getAndInitPage_error2;
    }
  }
  assert( (*ppPage)->pgno==pgno );
  assert( (*ppPage)->aData==sqlite3PagerGetData(pDbPage) );

  /* If obtaining a child page for a cursor, we must verify that the page is
  ** compatible with the root page. */
  if( pCur && ((*ppPage)->nCell<1 || (*ppPage)->intKey!=pCur->curIntKey) ){
    rc = SQLITE_CORRUPT_PGNO(pgno);

    goto getAndInitPage_error2;
  }
  return SQLITE_OK;

getAndInitPage_error2:
  releasePage(*ppPage);
getAndInitPage_error1:
  if( pCur ){
    pCur->iPage--;
    pCur->pPage = pCur->apPage[pCur->iPage];
  }
  testcase( pgno==0 );
  assert( pgno!=0 || rc==SQLITE_CORRUPT );
  return rc;
................................................................................
  int hdr;        /* Beginning of the header.  0 most pages.  100 page 1 */

  if( *pRC ) return;
  assert( idx>=0 && idx<pPage->nCell );
  assert( CORRUPT_DB || sz==cellSize(pPage, idx) );
  assert( sqlite3PagerIswriteable(pPage->pDbPage) );
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( pPage->nFree>=0 );
  data = pPage->aData;
  ptr = &pPage->aCellIdx[2*idx];
  pc = get2byte(ptr);
  hdr = pPage->hdrOffset;
  testcase( pc==get2byte(&data[hdr+5]) );
  testcase( pc+sz==pPage->pBt->usableSize );
  if( pc+sz > pPage->pBt->usableSize ){
................................................................................
  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  /* The cell should normally be sized correctly.  However, when moving a
  ** malformed cell from a leaf page to an interior page, if the cell size
  ** wanted to be less than 4 but got rounded up to 4 on the leaf, then size
  ** might be less than 8 (leaf-size + pointer) on the interior node.  Hence
  ** the term after the || in the following assert(). */
  assert( sz==pPage->xCellSize(pPage, pCell) || (sz==8 && iChild>0) );
  assert( pPage->nFree>=0 );
  if( pPage->nOverflow || sz+2>pPage->nFree ){
    if( pTemp ){
      memcpy(pTemp, pCell, sz);
      pCell = pTemp;
    }
    if( iChild ){
      put4byte(pCell, iChild);
................................................................................
**    ixNx[3] = Number of cells in Child-1 and Child-2 + both divider cells
**    ixNx[4] = Total number of cells.
**
** For a table-btree, the concept is similar, except only apEnd[0]..apEnd[2]
** are used and they point to the leaf pages only, and the ixNx value are:
**
**    ixNx[0] = Number of cells in Child-1.
**    ixNx[1] = Number of cells in Child-1 and Child-2.
**    ixNx[2] = Total number of cells.
**
** Sometimes when deleting, a child page can have zero cells.  In those
** cases, ixNx[] entries with higher indexes, and the corresponding apEnd[]
** entries, shift down.  The end result is that each ixNx[] entry should
** be larger than the previous
*/
typedef struct CellArray CellArray;
struct CellArray {
  int nCell;              /* Number of cells in apCell[] */
  MemPage *pRef;          /* Reference page */
  u8 **apCell;            /* All cells begin balanced */
  u16 *szCell;            /* Local size of all cells in apCell[] */
................................................................................
  MemPage *pNew;                       /* Newly allocated page */
  int rc;                              /* Return Code */
  Pgno pgnoNew;                        /* Page number of pNew */

  assert( sqlite3_mutex_held(pPage->pBt->mutex) );
  assert( sqlite3PagerIswriteable(pParent->pDbPage) );
  assert( pPage->nOverflow==1 );
  
  if( pPage->nCell==0 ) return SQLITE_CORRUPT_BKPT;  /* dbfuzz001.test */
  assert( pPage->nFree>=0 );
  assert( pParent->nFree>=0 );

  /* Allocate a new page. This page will become the right-sibling of 
  ** pPage. Make the parent page writable, so that the new divider cell
  ** may be inserted. If both these operations are successful, proceed.
  */
  rc = allocateBtreePage(pBt, &pNew, &pgnoNew, 0, 0);

................................................................................
    /* Reinitialize page pTo so that the contents of the MemPage structure
    ** match the new data. The initialization of pTo can actually fail under
    ** fairly obscure circumstances, even though it is a copy of initialized 
    ** page pFrom.
    */
    pTo->isInit = 0;
    rc = btreeInitPage(pTo);
    if( rc==SQLITE_OK ) rc = btreeComputeFreeSpace(pTo);
    if( rc!=SQLITE_OK ){
      *pRC = rc;
      return;
    }
  
    /* If this is an auto-vacuum database, update the pointer-map entries
    ** for any b-tree or overflow pages that pTo now contains the pointers to.
................................................................................
  */
  assert( pParent->nOverflow==0 || pParent->nOverflow==1 );
  assert( pParent->nOverflow==0 || pParent->aiOvfl[0]==iParentIdx );

  if( !aOvflSpace ){
    return SQLITE_NOMEM_BKPT;
  }
  assert( pParent->nFree>=0 );

  /* Find the sibling pages to balance. Also locate the cells in pParent 
  ** that divide the siblings. An attempt is made to find NN siblings on 
  ** either side of pPage. More siblings are taken from one side, however, 
  ** if there are fewer than NN siblings on the other side. If pParent
  ** has NB or fewer children then all children of pParent are taken.  
  **
................................................................................
  }
  pgno = get4byte(pRight);
  while( 1 ){
    rc = getAndInitPage(pBt, pgno, &apOld[i], 0, 0);
    if( rc ){
      memset(apOld, 0, (i+1)*sizeof(MemPage*));
      goto balance_cleanup;
    }
    if( apOld[i]->nFree<0 ){
      rc = btreeComputeFreeSpace(apOld[i]);
      if( rc ){
        memset(apOld, 0, (i)*sizeof(MemPage*));
        goto balance_cleanup;
      }
    }
    nMaxCells += 1+apOld[i]->nCell+apOld[i]->nOverflow;
    if( (i--)==0 ) break;

    if( pParent->nOverflow && i+nxDiv==pParent->aiOvfl[0] ){
      apDiv[i] = pParent->apOvfl[0];
      pgno = get4byte(apDiv[i]);
................................................................................
  ** 
  */
  usableSpace = pBt->usableSize - 12 + leafCorrection;
  for(i=k=0; i<nOld; i++, k++){
    MemPage *p = apOld[i];
    b.apEnd[k] = p->aDataEnd;
    b.ixNx[k] = cntOld[i];
    if( k && b.ixNx[k]==b.ixNx[k-1] ){
      k--;  /* Omit b.ixNx[] entry for child pages with no cells */
    }
    if( !leafData ){
      k++;
      b.apEnd[k] = pParent->aDataEnd;
      b.ixNx[k] = cntOld[i]+1;
    }
    assert( p->nFree>=0 );
    szNew[i] = usableSpace - p->nFree;
    for(j=0; j<p->nOverflow; j++){
      szNew[i] += 2 + p->xCellSize(p, p->apOvfl[j]);
    }
    cntNew[i] = cntOld[i];
  }
  k = nOld;
................................................................................
  ** associated with the right-child of each sibling may also need to be 
  ** updated. This happens below, after the sibling pages have been 
  ** populated, not here.
  */
  if( ISAUTOVACUUM ){
    MemPage *pOld;
    MemPage *pNew = pOld = apNew[0];

    int cntOldNext = pNew->nCell + pNew->nOverflow;

    int iNew = 0;
    int iOld = 0;

    for(i=0; i<b.nCell; i++){
      u8 *pCell = b.apCell[i];
      while( i==cntOldNext ){
        iOld++;
        assert( iOld<nNew || iOld<nOld );
        pOld = iOld<nNew ? apNew[iOld] : apOld[iOld];
        cntOldNext += pOld->nCell + pOld->nOverflow + !leafData;

      }
      if( i==cntNew[iNew] ){
        pNew = apNew[++iNew];
        if( !leafData ) continue;
      }

      /* Cell pCell is destined for new sibling page pNew. Originally, it
................................................................................
      ** was either part of sibling page iOld (possibly an overflow cell), 
      ** or else the divider cell to the left of sibling page iOld. So,
      ** if sibling page iOld had the same page number as pNew, and if
      ** pCell really was a part of sibling page iOld (not a divider or
      ** overflow cell), we can skip updating the pointer map entries.  */
      if( iOld>=nNew
       || pNew->pgno!=aPgno[iOld]
       || !SQLITE_WITHIN(pCell,pOld->aData,pOld->aDataEnd)
      ){
        if( !leafCorrection ){
          ptrmapPut(pBt, get4byte(pCell), PTRMAP_BTREE, pNew->pgno, &rc);
        }
        if( cachedCellSize(&b,i)>pNew->minLocal ){
          ptrmapPutOvflPtr(pNew, pOld, pCell, &rc);
        }
................................................................................
  VVA_ONLY( int balance_quick_called = 0 );
  VVA_ONLY( int balance_deeper_called = 0 );

  do {
    int iPage = pCur->iPage;
    MemPage *pPage = pCur->pPage;

    if( NEVER(pPage->nFree<0) && btreeComputeFreeSpace(pPage) ) break;
    if( iPage==0 ){
      if( pPage->nOverflow ){
        /* The root page of the b-tree is overfull. In this case call the
        ** balance_deeper() function to create a new child for the root-page
        ** and copy the current contents of the root-page to it. The
        ** next iteration of the do-loop will balance the child page.
        */ 
................................................................................
    }else if( pPage->nOverflow==0 && pPage->nFree<=nMin ){
      break;
    }else{
      MemPage * const pParent = pCur->apPage[iPage-1];
      int const iIdx = pCur->aiIdx[iPage-1];

      rc = sqlite3PagerWrite(pParent->pDbPage);
      if( rc==SQLITE_OK && pParent->nFree<0 ){
        rc = btreeComputeFreeSpace(pParent);
      }
      if( rc==SQLITE_OK ){
#ifndef SQLITE_OMIT_QUICKBALANCE
        if( pPage->intKeyLeaf
         && pPage->nOverflow==1
         && pPage->aiOvfl[0]==pPage->nCell
         && pParent->pgno!=1
         && pParent->nCell==iIdx
................................................................................

  }
  assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );

  pPage = pCur->pPage;
  assert( pPage->intKey || pX->nKey>=0 );
  assert( pPage->leaf || !pPage->intKey );
  if( pPage->nFree<0 ){
    rc = btreeComputeFreeSpace(pPage);
    if( rc ) return rc;
  }

  TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
          pCur->pgnoRoot, pX->nKey, pX->nData, pPage->pgno,
          loc==0 ? "overwrite" : "new entry"));
  assert( pPage->isInit );
  newCell = pBt->pTmpSpace;
  assert( newCell!=0 );
................................................................................
  assert( pCur->eState==CURSOR_VALID );
  assert( (flags & ~(BTREE_SAVEPOSITION | BTREE_AUXDELETE))==0 );

  iCellDepth = pCur->iPage;
  iCellIdx = pCur->ix;
  pPage = pCur->pPage;
  pCell = findCell(pPage, iCellIdx);
  if( pPage->nFree<0 && btreeComputeFreeSpace(pPage) ) return SQLITE_CORRUPT;

  /* If the bPreserve flag is set to true, then the cursor position must
  ** be preserved following this delete operation. If the current delete
  ** will cause a b-tree rebalance, then this is done by saving the cursor
  ** key and leaving the cursor in CURSOR_REQUIRESEEK state before 
  ** returning. 
  **
................................................................................
  ** node to replace the deleted cell.  */
  if( !pPage->leaf ){
    MemPage *pLeaf = pCur->pPage;
    int nCell;
    Pgno n;
    unsigned char *pTmp;

    if( pLeaf->nFree<0 ){
      rc = btreeComputeFreeSpace(pLeaf);
      if( rc ) return rc;
    }
    if( iCellDepth<pCur->iPage-1 ){
      n = pCur->apPage[iCellDepth+1]->pgno;
    }else{
      n = pCur->pPage->pgno;
    }
    pCell = findCell(pLeaf, pLeaf->nCell-1);
    if( pCell<&pLeaf->aData[4] ) return SQLITE_CORRUPT_BKPT;
................................................................................
  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;
  }
  if( (rc = btreeComputeFreeSpace(pPage))!=0 ){
    assert( rc==SQLITE_CORRUPT );
    checkAppendMsg(pCheck, "free space corruption", rc);
    goto end_of_check;
  }
  data = pPage->aData;
  hdr = pPage->hdrOffset;

  /* Set up for cell analysis */
  pCheck->zPfx = "On tree page %d cell %d: ";
  contentOffset = get2byteNotZero(&data[hdr+5]);
  assert( contentOffset<=usableSize );  /* Enforced by btreeInitPage() */
................................................................................
    ** EVIDENCE-OF: R-20690-50594 The second field of the b-tree page header
    ** is the offset of the first freeblock, or zero if there are no
    ** freeblocks on the page. 
    */
    i = get2byte(&data[hdr+1]);
    while( i>0 ){
      int size, j;
      assert( (u32)i<=usableSize-4 ); /* Enforced by btreeComputeFreeSpace() */
      size = get2byte(&data[i+2]);
      assert( (u32)(i+size)<=usableSize ); /* due to btreeComputeFreeSpace() */
      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 btreeComputeFreeSpace() */
      assert( (u32)j<=usableSize-4 ); /* Enforced by btreeComputeFreeSpace() */
      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

Changes to src/btreeInt.h.

282
283
284
285
286
287
288
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291
292
293
294
295
296
  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
  u8 max1bytePayload;  /* min(maxLocal,127) */
  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
  u16 cellOffset;      /* Index in aData of first cell pointer */
  u16 nFree;           /* Number of free bytes on the page */
  u16 nCell;           /* Number of cells on this page, local and ovfl */
  u16 maskPage;        /* Mask for page offset */
  u16 aiOvfl[4];       /* Insert the i-th overflow cell before the aiOvfl-th
                       ** non-overflow cell */
  u8 *apOvfl[4];       /* Pointers to the body of overflow cells */
  BtShared *pBt;       /* Pointer to BtShared that this page is part of */
  u8 *aData;           /* Pointer to disk image of the page data */







|







282
283
284
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286
287
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289
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296
  u8 hdrOffset;        /* 100 for page 1.  0 otherwise */
  u8 childPtrSize;     /* 0 if leaf==1.  4 if leaf==0 */
  u8 max1bytePayload;  /* min(maxLocal,127) */
  u8 nOverflow;        /* Number of overflow cell bodies in aCell[] */
  u16 maxLocal;        /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
  u16 minLocal;        /* Copy of BtShared.minLocal or BtShared.minLeaf */
  u16 cellOffset;      /* Index in aData of first cell pointer */
  int nFree;           /* Number of free bytes on the page. -1 for unknown */
  u16 nCell;           /* Number of cells on this page, local and ovfl */
  u16 maskPage;        /* Mask for page offset */
  u16 aiOvfl[4];       /* Insert the i-th overflow cell before the aiOvfl-th
                       ** non-overflow cell */
  u8 *apOvfl[4];       /* Pointers to the body of overflow cells */
  BtShared *pBt;       /* Pointer to BtShared that this page is part of */
  u8 *aData;           /* Pointer to disk image of the page data */

Changes to src/vdbe.c.

689
690
691
692
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695









696
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698
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...
890
891
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893
894
895
896

897
898
899
900
901
902
903
....
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
....
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2684

2685
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2688
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2691
2692
2693
2694
2695
....
7606
7607
7608
7609
7610
7611
7612
7613








7614
7615
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7617
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7620
#ifdef VDBE_PROFILE
  u64 start;                 /* CPU clock count at start of opcode */
#endif
  /*** INSERT STACK UNION HERE ***/

  assert( p->magic==VDBE_MAGIC_RUN );  /* sqlite3_step() verifies this */
  sqlite3VdbeEnter(p);









  if( p->rc==SQLITE_NOMEM ){
    /* This happens if a malloc() inside a call to sqlite3_column_text() or
    ** sqlite3_column_text16() failed.  */
    goto no_mem;
  }
  assert( p->rc==SQLITE_OK || (p->rc&0xff)==SQLITE_BUSY );
  assert( p->bIsReader || p->readOnly!=0 );
  p->iCurrentTime = 0;
  assert( p->explain==0 );
  p->pResultSet = 0;
  db->busyHandler.nBusy = 0;
  if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
  sqlite3VdbeIOTraceSql(p);
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( db->xProgress ){
    u32 iPrior = p->aCounter[SQLITE_STMTSTATUS_VM_STEP];
    assert( 0 < db->nProgressOps );
    nProgressLimit = db->nProgressOps - (iPrior % db->nProgressOps);
  }else{
    nProgressLimit = 0xffffffff;
  }
#endif
#ifdef SQLITE_DEBUG
  sqlite3BeginBenignMalloc();
  if( p->pc==0
   && (p->db->flags & (SQLITE_VdbeListing|SQLITE_VdbeEQP|SQLITE_VdbeTrace))!=0
  ){
    int i;
    int once = 1;
................................................................................
  ** If the progress callback returns non-zero, exit the virtual machine with
  ** a return code SQLITE_ABORT.
  */
  if( nVmStep>=nProgressLimit && db->xProgress!=0 ){
    assert( db->nProgressOps!=0 );
    nProgressLimit = nVmStep + db->nProgressOps - (nVmStep%db->nProgressOps);
    if( db->xProgress(db->pProgressArg) ){

      rc = SQLITE_INTERRUPT;
      goto abort_due_to_error;
    }
  }
#endif
  
  break;
................................................................................
case OP_ResultRow: {
  Mem *pMem;
  int i;
  assert( p->nResColumn==pOp->p2 );
  assert( pOp->p1>0 );
  assert( pOp->p1+pOp->p2<=(p->nMem+1 - p->nCursor)+1 );

#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  /* Run the progress counter just before returning.
  */
  if( db->xProgress!=0
   && nVmStep>=nProgressLimit 
   && db->xProgress(db->pProgressArg)!=0
  ){
    rc = SQLITE_INTERRUPT;
    goto abort_due_to_error;
  }
#endif

  /* If this statement has violated immediate foreign key constraints, do
  ** not return the number of rows modified. And do not RELEASE the statement
  ** transaction. It needs to be rolled back.  */
  if( SQLITE_OK!=(rc = sqlite3VdbeCheckFk(p, 0)) ){
    assert( db->flags&SQLITE_CountRows );
    assert( p->usesStmtJournal );
    goto abort_due_to_error;
................................................................................
    op_column_read_header:
      i = pC->nHdrParsed;
      offset64 = aOffset[i];
      zHdr = zData + pC->iHdrOffset;
      zEndHdr = zData + aOffset[0];
      testcase( zHdr>=zEndHdr );
      do{
        if( (t = zHdr[0])<0x80 ){
          zHdr++;
          offset64 += sqlite3VdbeOneByteSerialTypeLen(t);
        }else{
          zHdr += sqlite3GetVarint32(zHdr, &t);

          offset64 += sqlite3VdbeSerialTypeLen(t);
        }
        pC->aType[i++] = t;
        aOffset[i] = (u32)(offset64 & 0xffffffff);
      }while( i<=p2 && zHdr<zEndHdr );

      /* The record is corrupt if any of the following are true:
      ** (1) the bytes of the header extend past the declared header size
      ** (2) the entire header was used but not all data was used
      ** (3) the end of the data extends beyond the end of the record.
      */
................................................................................
    sqlite3ResetOneSchema(db, resetSchemaOnFault-1);
  }

  /* This is the only way out of this procedure.  We have to
  ** release the mutexes on btrees that were acquired at the
  ** top. */
vdbe_return:
  testcase( nVmStep>0 );








  p->aCounter[SQLITE_STMTSTATUS_VM_STEP] += (int)nVmStep;
  sqlite3VdbeLeave(p);
  assert( rc!=SQLITE_OK || nExtraDelete==0 
       || sqlite3_strlike("DELETE%",p->zSql,0)!=0 
  );
  return rc;








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689
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718
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723
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...
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900
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904
....
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1443
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....
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#ifdef VDBE_PROFILE
  u64 start;                 /* CPU clock count at start of opcode */
#endif
  /*** INSERT STACK UNION HERE ***/

  assert( p->magic==VDBE_MAGIC_RUN );  /* sqlite3_step() verifies this */
  sqlite3VdbeEnter(p);
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( db->xProgress ){
    u32 iPrior = p->aCounter[SQLITE_STMTSTATUS_VM_STEP];
    assert( 0 < db->nProgressOps );
    nProgressLimit = db->nProgressOps - (iPrior % db->nProgressOps);
  }else{
    nProgressLimit = 0xffffffff;
  }
#endif
  if( p->rc==SQLITE_NOMEM ){
    /* This happens if a malloc() inside a call to sqlite3_column_text() or
    ** sqlite3_column_text16() failed.  */
    goto no_mem;
  }
  assert( p->rc==SQLITE_OK || (p->rc&0xff)==SQLITE_BUSY );
  assert( p->bIsReader || p->readOnly!=0 );
  p->iCurrentTime = 0;
  assert( p->explain==0 );
  p->pResultSet = 0;
  db->busyHandler.nBusy = 0;
  if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
  sqlite3VdbeIOTraceSql(p);









#ifdef SQLITE_DEBUG
  sqlite3BeginBenignMalloc();
  if( p->pc==0
   && (p->db->flags & (SQLITE_VdbeListing|SQLITE_VdbeEQP|SQLITE_VdbeTrace))!=0
  ){
    int i;
    int once = 1;
................................................................................
  ** If the progress callback returns non-zero, exit the virtual machine with
  ** a return code SQLITE_ABORT.
  */
  if( nVmStep>=nProgressLimit && db->xProgress!=0 ){
    assert( db->nProgressOps!=0 );
    nProgressLimit = nVmStep + db->nProgressOps - (nVmStep%db->nProgressOps);
    if( db->xProgress(db->pProgressArg) ){
      nProgressLimit = 0xffffffff;
      rc = SQLITE_INTERRUPT;
      goto abort_due_to_error;
    }
  }
#endif
  
  break;
................................................................................
case OP_ResultRow: {
  Mem *pMem;
  int i;
  assert( p->nResColumn==pOp->p2 );
  assert( pOp->p1>0 );
  assert( pOp->p1+pOp->p2<=(p->nMem+1 - p->nCursor)+1 );













  /* If this statement has violated immediate foreign key constraints, do
  ** not return the number of rows modified. And do not RELEASE the statement
  ** transaction. It needs to be rolled back.  */
  if( SQLITE_OK!=(rc = sqlite3VdbeCheckFk(p, 0)) ){
    assert( db->flags&SQLITE_CountRows );
    assert( p->usesStmtJournal );
    goto abort_due_to_error;
................................................................................
    op_column_read_header:
      i = pC->nHdrParsed;
      offset64 = aOffset[i];
      zHdr = zData + pC->iHdrOffset;
      zEndHdr = zData + aOffset[0];
      testcase( zHdr>=zEndHdr );
      do{
        if( (pC->aType[i] = t = zHdr[0])<0x80 ){
          zHdr++;
          offset64 += sqlite3VdbeOneByteSerialTypeLen(t);
        }else{
          zHdr += sqlite3GetVarint32(zHdr, &t);
          pC->aType[i] = t;
          offset64 += sqlite3VdbeSerialTypeLen(t);
        }

        aOffset[++i] = (u32)(offset64 & 0xffffffff);
      }while( i<=p2 && zHdr<zEndHdr );

      /* The record is corrupt if any of the following are true:
      ** (1) the bytes of the header extend past the declared header size
      ** (2) the entire header was used but not all data was used
      ** (3) the end of the data extends beyond the end of the record.
      */
................................................................................
    sqlite3ResetOneSchema(db, resetSchemaOnFault-1);
  }

  /* This is the only way out of this procedure.  We have to
  ** release the mutexes on btrees that were acquired at the
  ** top. */
vdbe_return:
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
  if( nVmStep>=nProgressLimit && db->xProgress!=0 ){
    if( db->xProgress(db->pProgressArg) ){
      nProgressLimit = 0xffffffff;
      rc = SQLITE_INTERRUPT;
      goto abort_due_to_error;
    }
  }
#endif
  p->aCounter[SQLITE_STMTSTATUS_VM_STEP] += (int)nVmStep;
  sqlite3VdbeLeave(p);
  assert( rc!=SQLITE_OK || nExtraDelete==0 
       || sqlite3_strlike("DELETE%",p->zSql,0)!=0 
  );
  return rc;

Changes to test/corrupt2.test.

91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
...
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
  set f [open corrupt.db RDWR]
  fconfigure $f -encoding binary
  seek $f 101 start
  puts -nonewline $f "\xFF\xFF"
  close $f

  sqlite3 db2 corrupt.db
  catchsql "
    $::presql
    SELECT * FROM sqlite_master;
  " db2
} {1 {database disk image is malformed}}

do_test corrupt2-1.5 {
  db2 close

  # Corrupt the free-block list on page 1.
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
................................................................................
  puts -nonewline $f "\x00\xC8"
  seek $f 200 start
  puts -nonewline $f "\x00\x00"
  puts -nonewline $f "\x10\x00"
  close $f

  sqlite3 db2 corrupt.db
  catchsql "
    $::presql
    SELECT * FROM sqlite_master;
  " db2
} {1 {database disk image is malformed}}
db2 close

# Corrupt a database by having 2 indices of the same name:
do_test corrupt2-2.1 {

  forcedelete corrupt.db
  forcedelete corrupt.db-journal







|
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91
92
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114
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124
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130
  set f [open corrupt.db RDWR]
  fconfigure $f -encoding binary
  seek $f 101 start
  puts -nonewline $f "\xFF\xFF"
  close $f

  sqlite3 db2 corrupt.db
  # Note: This test is no longer meaningful due to the deferred computation
  # of MemPage.nFree 
  catchsql {PRAGMA quick_check} db2
} {0 {{*** in database main ***
Page 1: free space corruption}}}

do_test corrupt2-1.5 {
  db2 close

  # Corrupt the free-block list on page 1.
  forcedelete corrupt.db
  forcedelete corrupt.db-journal
................................................................................
  puts -nonewline $f "\x00\xC8"
  seek $f 200 start
  puts -nonewline $f "\x00\x00"
  puts -nonewline $f "\x10\x00"
  close $f

  sqlite3 db2 corrupt.db
  catchsql {PRAGMA quick_check} db2
} {0 {{*** in database main ***
Page 1: free space corruption}}}


db2 close

# Corrupt a database by having 2 indices of the same name:
do_test corrupt2-2.1 {

  forcedelete corrupt.db
  forcedelete corrupt.db-journal

Changes to test/corruptD.test.

107
108
109
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113
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115

116
117
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122
#-------------------------------------------------------------------------
# The following tests, corruptD-1.1.*, focus on the page header field
# containing the offset of the first free block in a page. 
#
do_test corruptD-1.1.1 {
  incr_change_counter
  hexio_write test.db [expr 1024+1] FFFF
  catchsql { SELECT * FROM t1 ORDER BY rowid }
} {1 {database disk image is malformed}}

do_test corruptD-1.1.2 {
  incr_change_counter
  hexio_write test.db [expr 1024+1] [hexio_render_int32 1021]
  catchsql { SELECT * FROM t1 ORDER BY rowid }
} {1 {database disk image is malformed}}

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







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107
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123
#-------------------------------------------------------------------------
# The following tests, corruptD-1.1.*, focus on the page header field
# containing the offset of the first free block in a page. 
#
do_test corruptD-1.1.1 {
  incr_change_counter
  hexio_write test.db [expr 1024+1] FFFF
  catchsql { PRAGMA quick_check }
} {0 {{*** in database main ***
Page 2: free space corruption}}}
do_test corruptD-1.1.2 {
  incr_change_counter
  hexio_write test.db [expr 1024+1] [hexio_render_int32 1021]
  catchsql { SELECT * FROM t1 ORDER BY rowid }
} {1 {database disk image is malformed}}

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

Changes to test/corruptK.test.

64
65
66
67
68
69
70





71
72
73

74
75
76
77
78
79
80
  seek $fd 30
  puts -nonewline $fd "\x18"
  close $fd
} {}
do_execsql_test 1.3 {
  INSERT INTO t1 VALUES(randomblob(20));
}





do_catchsql_test 1.4 {
  INSERT INTO t1 VALUES(randomblob(90));
} {1 {database disk image is malformed}}


#-------------------------------------------------------------------------
reset_db
do_execsql_test 2.1 {
  PRAGMA page_size=1024;
  PRAGMA auto_vacuum=0;
  CREATE TABLE t1(x);







>
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64
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66
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70
71
72
73
74
75
76
77
78
79
80
81
82
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86
  seek $fd 30
  puts -nonewline $fd "\x18"
  close $fd
} {}
do_execsql_test 1.3 {
  INSERT INTO t1 VALUES(randomblob(20));
}

# This test no longer functions due to the deferred computation of
# MemPage.nFree.
#
if 0 {
do_catchsql_test 1.4 {
  INSERT INTO t1 VALUES(randomblob(90));
} {1 {database disk image is malformed}}
}

#-------------------------------------------------------------------------
reset_db
do_execsql_test 2.1 {
  PRAGMA page_size=1024;
  PRAGMA auto_vacuum=0;
  CREATE TABLE t1(x);

Changes to test/fuzzdata8.db.

cannot compute difference between binary files