SQLite

    }else{
      int rc = sqlite3_reset(pCsr->pStmt);
      if( rc==SQLITE_OK ){
        /* If no row was found and no error has occured, then the %_content
        ** table is missing a row that is present in the full-text index.
        ** The data structures are corrupt.
        */
        rc = FTS_CORRUPT_VTAB;
      }
      pCsr->isEof = 1;
      if( pContext ){
        sqlite3_result_error_code(pContext, rc);
      }
      return rc;
    }

  ** contents, or two zero bytes. Or, if the node is read from the %_segments
  ** table, then there are always 20 bytes of zeroed padding following the
  ** nNode bytes of content (see sqlite3Fts3ReadBlock() for details).
  */
  zCsr += sqlite3Fts3GetVarint(zCsr, &iChild);
  zCsr += sqlite3Fts3GetVarint(zCsr, &iChild);
  if( zCsr>zEnd ){
    return FTS_CORRUPT_VTAB;
  }
  
  while( zCsr<zEnd && (piFirst || piLast) ){
    int cmp;                      /* memcmp() result */
    int nSuffix;                  /* Size of term suffix */
    int nPrefix = 0;              /* Size of term prefix */
    int nBuffer;                  /* Total term size */
  
    /* Load the next term on the node into zBuffer. Use realloc() to expand
    ** the size of zBuffer if required.  */
    if( !isFirstTerm ){
      zCsr += sqlite3Fts3GetVarint32(zCsr, &nPrefix);
    }
    isFirstTerm = 0;
    zCsr += sqlite3Fts3GetVarint32(zCsr, &nSuffix);
    
    if( nPrefix<0 || nSuffix<0 || &zCsr[nSuffix]>zEnd ){
      rc = FTS_CORRUPT_VTAB;
      goto finish_scan;
    }
    if( nPrefix+nSuffix>nAlloc ){
      char *zNew;
      nAlloc = (nPrefix+nSuffix) * 2;
      zNew = (char *)sqlite3_realloc(zBuffer, nAlloc);
      if( !zNew ){

    pEnd = &a[sqlite3_column_bytes(pStmt, 0)];
    a += sqlite3Fts3GetVarint(a, &nDoc);
    while( a<pEnd ){
      a += sqlite3Fts3GetVarint(a, &nByte);
    }
    if( nDoc==0 || nByte==0 ){
      sqlite3_reset(pStmt);
      return FTS_CORRUPT_VTAB;
    }

    pCsr->nDoc = nDoc;
    pCsr->nRowAvg = (int)(((nByte / nDoc) + p->nPgsz) / p->nPgsz);
    assert( pCsr->nRowAvg>0 ); 
    rc = sqlite3_reset(pStmt);
    if( rc!=SQLITE_OK ) return rc;

    for(i=0; i<pPhrase->nToken; i++){
      fts3SegReaderCursorFree(pPhrase->aToken[i].pSegcsr);
      pPhrase->aToken[i].pSegcsr = 0;
    }
  }
}

/*
** Return SQLITE_CORRUPT_VTAB.
*/
#ifdef SQLITE_DEBUG
int sqlite3Fts3Corrupt(){
  return SQLITE_CORRUPT_VTAB;
}
#endif

#if !SQLITE_CORE
/*
** Initialize API pointer table, if required.
*/
int sqlite3_extension_init(
  sqlite3 *db, 
  char **pzErrMsg,

#if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
# define TESTONLY(X)  X
#else
# define TESTONLY(X)
#endif

#endif /* SQLITE_AMALGAMATION */

#ifdef SQLITE_DEBUG
int sqlite3Fts3Corrupt(void);
# define FTS_CORRUPT_VTAB sqlite3Fts3Corrupt()
#else
# define FTS_CORRUPT_VTAB SQLITE_CORRUPT_VTAB
#endif

typedef struct Fts3Table Fts3Table;
typedef struct Fts3Cursor Fts3Cursor;
typedef struct Fts3Expr Fts3Expr;
typedef struct Fts3Phrase Fts3Phrase;
typedef struct Fts3PhraseToken Fts3PhraseToken;

    if( rc!=SQLITE_OK ) return rc;
  }
  pStmt = *ppStmt;
  assert( sqlite3_data_count(pStmt)==1 );

  a = sqlite3_column_blob(pStmt, 0);
  a += sqlite3Fts3GetVarint(a, &nDoc);
  if( nDoc==0 ) return FTS_CORRUPT_VTAB;
  *pnDoc = (u32)nDoc;

  if( paLen ) *paLen = a;
  return SQLITE_OK;
}

/*

        if( rc==SQLITE_OK ){
          char aBuffer[64];
          sqlite3_snprintf(sizeof(aBuffer), aBuffer, 
              "%d %d %d %d ", iCol, pTerm-sCtx.aTerm, iStart, iEnd-iStart
          );
          rc = fts3StringAppend(&res, aBuffer, -1);
        }else if( rc==SQLITE_DONE ){
          rc = FTS_CORRUPT_VTAB;
        }
      }
    }
    if( rc==SQLITE_DONE ){
      rc = SQLITE_OK;
    }

  if( rc==SQLITE_OK ){
    if( eStmt==SQL_SELECT_DOCSIZE ){
      sqlite3_bind_int64(pStmt, 1, iDocid);
    }
    rc = sqlite3_step(pStmt);
    if( rc!=SQLITE_ROW || sqlite3_column_type(pStmt, 0)!=SQLITE_BLOB ){
      rc = sqlite3_reset(pStmt);
      if( rc==SQLITE_OK ) rc = FTS_CORRUPT_VTAB;
      pStmt = 0;
    }else{
      rc = SQLITE_OK;
    }
  }

  *ppStmt = pStmt;

  /* Because of the FTS3_NODE_PADDING bytes of padding, the following is 
  ** safe (no risk of overread) even if the node data is corrupted. */
  pNext += sqlite3Fts3GetVarint32(pNext, &nPrefix);
  pNext += sqlite3Fts3GetVarint32(pNext, &nSuffix);
  if( nPrefix<0 || nSuffix<=0 
   || &pNext[nSuffix]>&pReader->aNode[pReader->nNode] 
  ){
    return FTS_CORRUPT_VTAB;
  }

  if( nPrefix+nSuffix>pReader->nTermAlloc ){
    int nNew = (nPrefix+nSuffix)*2;
    char *zNew = sqlite3_realloc(pReader->zTerm, nNew);
    if( !zNew ){
      return SQLITE_NOMEM;

  /* Check that the doclist does not appear to extend past the end of the
  ** b-tree node. And that the final byte of the doclist is 0x00. If either 
  ** of these statements is untrue, then the data structure is corrupt.
  */
  if( &pReader->aDoclist[pReader->nDoclist]>&pReader->aNode[pReader->nNode] 
   || (pReader->nPopulate==0 && pReader->aDoclist[pReader->nDoclist-1])
  ){
    return FTS_CORRUPT_VTAB;
  }
  return SQLITE_OK;
}

/*
** Set the SegReader to point to the first docid in the doclist associated
** with the current term.

  int nArg,                       /* Size of argument array */
  sqlite3_value **apVal,          /* Array of arguments */
  sqlite_int64 *pRowid            /* OUT: The affected (or effected) rowid */
){
  Fts3Table *p = (Fts3Table *)pVtab;
  int rc = SQLITE_OK;             /* Return Code */
  int isRemove = 0;               /* True for an UPDATE or DELETE */

  u32 *aSzIns = 0;                /* Sizes of inserted documents */
  u32 *aSzDel;                    /* Sizes of deleted documents */
  int nChng = 0;                  /* Net change in number of documents */
  int bInsertDone = 0;

  assert( p->pSegments==0 );

  }

  /* If this is a DELETE or UPDATE operation, remove the old record. */
  if( sqlite3_value_type(apVal[0])!=SQLITE_NULL ){
    assert( sqlite3_value_type(apVal[0])==SQLITE_INTEGER );
    rc = fts3DeleteByRowid(p, apVal[0], &nChng, aSzDel);
    isRemove = 1;

  }
  
  /* If this is an INSERT or UPDATE operation, insert the new record. */
  if( nArg>1 && rc==SQLITE_OK ){
    if( bInsertDone==0 ){
      rc = fts3InsertData(p, apVal, pRowid);
      if( rc==SQLITE_CONSTRAINT ) rc = FTS_CORRUPT_VTAB;
    }
    if( rc==SQLITE_OK && (!isRemove || *pRowid!=p->iPrevDocid ) ){
      rc = fts3PendingTermsDocid(p, *pRowid);
    }
    if( rc==SQLITE_OK ){
      assert( p->iPrevDocid==*pRowid );
      rc = fts3InsertTerms(p, apVal, aSzIns);
    }
    if( p->bHasDocsize ){
      fts3InsertDocsize(&rc, p, aSzIns);
    }
    nChng++;
  }

# 2011 October 13
#
#    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 regression tests for the FTS SQLite module.
#
# This file implements tests to verify that ticket [9fd058691] has been
# fixed.  
#

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

# If SQLITE_ENABLE_FTS3 is defined, omit this file.
ifcapable !fts3 {
  finish_test
  return
}

set ::testprefix fts3-9fd058691

do_execsql_test 1.0 {
  CREATE VIRTUAL TABLE fts USING fts3( tags TEXT);
  INSERT INTO fts (tags) VALUES ('tag1');
  SELECT * FROM fts WHERE tags MATCH 'tag1';
} {tag1}

do_test 1.1 {
  db close
  sqlite3 db test.db
  execsql {
    UPDATE fts SET tags = 'tag1' WHERE rowid = 1;
    SELECT * FROM fts WHERE tags MATCH 'tag1';
  }
} {tag1}

db close
forcedelete test.db
sqlite3 db test.db

do_execsql_test 2.0 {
  CREATE VIRTUAL TABLE fts USING fts3(tags TEXT);
  INSERT INTO fts (docid, tags) VALUES (1, 'tag1');
  INSERT INTO fts (docid, tags) VALUES (2, NULL);
  INSERT INTO fts (docid, tags) VALUES (3, 'three');
} {}

do_test 2.1 {
  execsql {
    UPDATE fts SET tags = 'two' WHERE rowid = 2;
    SELECT * FROM fts WHERE tags MATCH 'two';
  }
} {two}

finish_test