SQLite

  }else{
    rc = SQLITE_OK;
  }

  return rc;
}

/*
** FTS maintains a separate indexes for each language-id (a 32-bit integer).
** Within each language id, a separate index is maintained to store the
** document terms, and each configured prefix size (configured the FTS 
** "prefix=" option). And each index consists of multiple levels ("relative
** levels").
**
** All three of these values (the language id, the specific index and the
** level within the index) are encoded in 64-bit integer values stored
** in the %_segdir table on disk. This function is used to convert three
** separate component values into the single 64-bit integer value that
** can be used to query the %_segdir table.
**
** Specifically, each language-id/index combination is allocated 1024 
** 64-bit integer level values ("absolute levels"). The main terms index
** for language-id 0 is allocate values 0-1023. The first prefix index
** (if any) for language-id 0 is allocated values 1024-2047. And so on.
** Language 1 indexes are allocated immediately following language 0.
**
** So, for a system with nPrefix prefix indexes configured, the block of
** absolute levels that corresponds to language-id iLangid and index 
** iIndex starts at absolute level ((iLangid * (nPrefix+1) + iIndex) * 1024).
*/
static sqlite3_int64 getAbsoluteLevel(
  Fts3Table *p, 
  int iLangid, 
  int iIndex, 
  int iLevel
){
  sqlite3_int64 iBase;            /* First absolute level for iLangid/iIndex */
  assert( iLangid>=0 );
  assert( p->nIndex>0 );
  assert( iIndex>=0 && iIndex<p->nIndex );

  iBase = ((sqlite3_int64)iLangid * p->nIndex + iIndex) * FTS3_SEGDIR_MAXLEVEL;
  return iBase + iLevel;
}


/*
** Set *ppStmt to a statement handle that may be used to iterate through
** all rows in the %_segdir table, from oldest to newest. If successful,
** return SQLITE_OK. If an error occurs while preparing the statement, 

**   3: end_block
**   4: root
*/
int sqlite3Fts3AllSegdirs(
  Fts3Table *p,                   /* FTS3 table */
  int iLangid,                    /* Language being queried */
  int iIndex,                     /* Index for p->aIndex[] */
  int iLevel,                     /* Level to select (relative level) */
  sqlite3_stmt **ppStmt           /* OUT: Compiled statement */
){
  int rc;
  sqlite3_stmt *pStmt = 0;

  assert( iLevel==FTS3_SEGCURSOR_ALL || iLevel>=0 );
  assert( iLevel<FTS3_SEGDIR_MAXLEVEL );
  assert( iIndex>=0 && iIndex<p->nIndex );

  if( iLevel<0 ){
    /* "SELECT * FROM %_segdir WHERE level BETWEEN ? AND ? ORDER BY ..." */
    rc = fts3SqlStmt(p, SQL_SELECT_LEVEL_RANGE, &pStmt, 0);
    if( rc==SQLITE_OK ){ 
      sqlite3_bind_int64(pStmt, 1, getAbsoluteLevel(p, iLangid, iIndex, 0));
      sqlite3_bind_int64(pStmt, 2, 
          getAbsoluteLevel(p, iLangid, iIndex, FTS3_SEGDIR_MAXLEVEL-1)
      );
    }
  }else{
    /* "SELECT * FROM %_segdir WHERE level = ? ORDER BY ..." */
    rc = fts3SqlStmt(p, SQL_SELECT_LEVEL, &pStmt, 0);
    if( rc==SQLITE_OK ){ 
      sqlite3_bind_int64(pStmt, 1, getAbsoluteLevel(p, iLangid, iIndex,iLevel));
    }
  }
  *ppStmt = pStmt;
  return rc;
}

}

/* 
** Insert a record into the %_segdir table.
*/
static int fts3WriteSegdir(
  Fts3Table *p,                   /* Virtual table handle */
  sqlite3_int64 iLevel,           /* Value for "level" field (absolute level) */
  int iIdx,                       /* Value for "idx" field */
  sqlite3_int64 iStartBlock,      /* Value for "start_block" field */
  sqlite3_int64 iLeafEndBlock,    /* Value for "leaves_end_block" field */
  sqlite3_int64 iEndBlock,        /* Value for "end_block" field */
  char *zRoot,                    /* Blob value for "root" field */
  int nRoot                       /* Number of bytes in buffer zRoot */
){
  sqlite3_stmt *pStmt;
  int rc = fts3SqlStmt(p, SQL_INSERT_SEGDIR, &pStmt, 0);
  if( rc==SQLITE_OK ){
    sqlite3_bind_int64(pStmt, 1, iLevel);
    sqlite3_bind_int(pStmt, 2, iIdx);
    sqlite3_bind_int64(pStmt, 3, iStartBlock);
    sqlite3_bind_int64(pStmt, 4, iLeafEndBlock);
    sqlite3_bind_int64(pStmt, 5, iEndBlock);
    sqlite3_bind_blob(pStmt, 6, zRoot, nRoot, SQLITE_STATIC);
    sqlite3_step(pStmt);
    rc = sqlite3_reset(pStmt);

** database. This function must be called after all terms have been added
** to the segment using fts3SegWriterAdd(). If successful, SQLITE_OK is
** returned. Otherwise, an SQLite error code.
*/
static int fts3SegWriterFlush(
  Fts3Table *p,                   /* Virtual table handle */
  SegmentWriter *pWriter,         /* SegmentWriter to flush to the db */
  sqlite3_int64 iLevel,           /* Value for 'level' column of %_segdir */
  int iIdx                        /* Value for 'idx' column of %_segdir */
){
  int rc;                         /* Return code */
  if( pWriter->pTree ){
    sqlite3_int64 iLast = 0;      /* Largest block id written to database */
    sqlite3_int64 iLastLeaf;      /* Largest leaf block id written to db */
    char *zRoot = NULL;           /* Pointer to buffer containing root node */

**
** Return SQLITE_OK if successful, or an SQLite error code if not.
*/
static int fts3SegmentMaxLevel(
  Fts3Table *p, 
  int iLangid,
  int iIndex, 
  sqlite3_int64 *pnMax
){
  sqlite3_stmt *pStmt;
  int rc;
  assert( iIndex>=0 && iIndex<p->nIndex );

  /* Set pStmt to the compiled version of:
  **
  **   SELECT max(level) FROM %Q.'%q_segdir' WHERE level BETWEEN ? AND ?
  **
  ** (1024 is actually the value of macro FTS3_SEGDIR_PREFIXLEVEL_STR).
  */
  rc = fts3SqlStmt(p, SQL_SELECT_SEGDIR_MAX_LEVEL, &pStmt, 0);
  if( rc!=SQLITE_OK ) return rc;
  sqlite3_bind_int64(pStmt, 1, getAbsoluteLevel(p, iLangid, iIndex, 0));
  sqlite3_bind_int64(pStmt, 2, 
      getAbsoluteLevel(p, iLangid, iIndex, FTS3_SEGDIR_MAXLEVEL-1)
  );
  if( SQLITE_ROW==sqlite3_step(pStmt) ){
    *pnMax = sqlite3_column_int64(pStmt, 0);
  }
  return sqlite3_reset(pStmt);
}

/*
** This function is used after merging multiple segments into a single large
** segment to delete the old, now redundant, segment b-trees. Specifically,

    return rc;
  }

  assert( iLevel>=0 || iLevel==FTS3_SEGCURSOR_ALL );
  if( iLevel==FTS3_SEGCURSOR_ALL ){
    rc = fts3SqlStmt(p, SQL_DELETE_SEGDIR_RANGE, &pDelete, 0);
    if( rc==SQLITE_OK ){
      sqlite3_bind_int64(pDelete, 1, getAbsoluteLevel(p, iLangid, iIndex, 0));
      sqlite3_bind_int64(pDelete, 2, 
          getAbsoluteLevel(p, iLangid, iIndex, FTS3_SEGDIR_MAXLEVEL-1)
      );
    }
  }else{
    rc = fts3SqlStmt(p, SQL_DELETE_SEGDIR_LEVEL, &pDelete, 0);
    if( rc==SQLITE_OK ){
      sqlite3_bind_int64(
          pDelete, 1, getAbsoluteLevel(p, iLangid, iIndex, iLevel)
      );
    }
  }

  if( rc==SQLITE_OK ){
    sqlite3_step(pDelete);
    rc = sqlite3_reset(pDelete);
  }

  Fts3Table *p, 
  int iLangid,                    /* Language id to merge */
  int iIndex,                     /* Index in p->aIndex[] to merge */
  int iLevel                      /* Level to merge */
){
  int rc;                         /* Return code */
  int iIdx = 0;                   /* Index of new segment */
  sqlite3_int64 iNewLevel = 0;    /* Level/index to create new segment at */
  SegmentWriter *pWriter = 0;     /* Used to write the new, merged, segment */
  Fts3SegFilter filter;           /* Segment term filter condition */
  Fts3MultiSegReader csr;         /* Cursor to iterate through level(s) */
  int bIgnoreEmpty = 0;           /* True to ignore empty segments */

  assert( iLevel==FTS3_SEGCURSOR_ALL
       || iLevel==FTS3_SEGCURSOR_PENDING

  do_execsql_test 4.1.4.$i {
    SELECT count(*) FROM t4 WHERE t4 MATCH 'fox' AND lid=$i;
  } [expr 0==($i%2)]
}
do_catchsql_test 4.1.5 {
  INSERT INTO t4(content, lid) VALUES('hello world', 101)
} {1 {SQL logic error or missing database}}

#-------------------------------------------------------------------------
# Test cases 5.*
#
# The following test cases are designed to detect a 32-bit overflow bug
# that existed at one point.
#
proc build_multilingual_db_3 {db} {
  $db eval {
    CREATE VIRTUAL TABLE t5 USING fts4(languageid=lid);
  }
  set languages [list 0 1 2 [expr 1<<30]]

  foreach lid $languages {
    execsql {
      INSERT INTO t5(docid, content, lid) VALUES(
          $lid, 'My language is ' || $lid, $lid
      ) 
    }
  }
}

do_test 5.1.0 {
  reset_db
  build_multilingual_db_3 db
} {}

do_execsql_test 5.1.1 {
  SELECT level FROM t5_segdir;
} [list 0 1024 2048 [expr 1<<40]]

do_execsql_test 5.1.2 {SELECT docid FROM t5 WHERE t5 MATCH 'language'} 0
foreach langid [list 0 1 2 [expr 1<<30]] {
  do_execsql_test 5.2.$langid { 
    SELECT docid FROM t5 WHERE t5 MATCH 'language' AND lid = $langid
  } $langid
}

set lid [expr 1<<30]
do_execsql_test 5.3.1 {
  CREATE VIRTUAL TABLE t6 USING fts4(languageid=lid);
  INSERT INTO t6 VALUES('I belong to language 0!');
}
do_test 5.3.2 {
  for {set i 0} {$i < 20} {incr i} {
    execsql {
      INSERT INTO t6(content, lid) VALUES(
        'I (row '||$i||') belong to langauge N!', $lid
      );
    }
  }
  execsql { SELECT docid FROM t6 WHERE t6 MATCH 'belong' }
} {1}

do_test 5.3.3 {
  execsql { SELECT docid FROM t6 WHERE t6 MATCH 'belong' AND lid=$lid}
} {2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21}

do_execsql_test 5.3.4 { INSERT INTO t6(t6) VALUES('optimize') } {}
do_execsql_test 5.3.5 { SELECT docid FROM t6 WHERE t6 MATCH 'belong' } {1}
do_execsql_test 5.3.6 { 
  SELECT docid FROM t6 WHERE t6 MATCH 'belong' AND lid=$lid
} {2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21}


set lid [expr 1<<30]
foreach lid [list 4 [expr 1<<30]] {
  do_execsql_test 5.4.$lid.1 {
    DELETE FROM t6;
    SELECT count(*) FROM t6_segdir;
    SELECT count(*) FROM t6_segments;
  } {0 0}
  do_execsql_test 5.4.$lid.2 {
    INSERT INTO t6(content, lid) VALUES('zero zero zero', $lid);
    INSERT INTO t6(content, lid) VALUES('zero zero one', $lid);
    INSERT INTO t6(content, lid) VALUES('zero one zero', $lid);
    INSERT INTO t6(content, lid) VALUES('zero one one', $lid);
    INSERT INTO t6(content, lid) VALUES('one zero zero', $lid);
    INSERT INTO t6(content, lid) VALUES('one zero one', $lid);
    INSERT INTO t6(content, lid) VALUES('one one zero', $lid);
    INSERT INTO t6(content, lid) VALUES('one one one', $lid);

    SELECT docid FROM t6 WHERE t6 MATCH '"zero zero"' AND lid=$lid;
  } {1 2 5}

  do_execsql_test 5.4.$lid.3 {
    SELECT count(*) FROM t6_segdir;
    SELECT count(*) FROM t6_segments;
  } {8 0}

  do_execsql_test 5.4.$lid.4 {
    INSERT INTO t6(t6) VALUES('optimize');
    SELECT docid FROM t6 WHERE t6 MATCH '"zero zero"' AND lid=$lid;
  } {1 2 5}

  do_execsql_test 5.4.$lid.5 {
    SELECT count(*) FROM t6_segdir;
    SELECT count(*) FROM t6_segments;
  } {1 0}
}


finish_test