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Unified Diff: third_party/sqlite/sqlite-src-3080704/ext/fts3/fts3_write.c

Issue 2363173002: [sqlite] Remove obsolete reference version 3.8.7.4. (Closed)
Patch Set: Created 4 years, 3 months ago
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Index: third_party/sqlite/sqlite-src-3080704/ext/fts3/fts3_write.c
diff --git a/third_party/sqlite/sqlite-src-3080704/ext/fts3/fts3_write.c b/third_party/sqlite/sqlite-src-3080704/ext/fts3/fts3_write.c
deleted file mode 100644
index 0da08c62d8bd05f7650b428d254d66369244193b..0000000000000000000000000000000000000000
--- a/third_party/sqlite/sqlite-src-3080704/ext/fts3/fts3_write.c
+++ /dev/null
@@ -1,5660 +0,0 @@
-/*
-** 2009 Oct 23
-**
-** The author disclaims copyright to this source code. In place of
-** a legal notice, here is a blessing:
-**
-** May you do good and not evil.
-** May you find forgiveness for yourself and forgive others.
-** May you share freely, never taking more than you give.
-**
-******************************************************************************
-**
-** This file is part of the SQLite FTS3 extension module. Specifically,
-** this file contains code to insert, update and delete rows from FTS3
-** tables. It also contains code to merge FTS3 b-tree segments. Some
-** of the sub-routines used to merge segments are also used by the query
-** code in fts3.c.
-*/
-
-#include "fts3Int.h"
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
-
-#include <string.h>
-#include <assert.h>
-#include <stdlib.h>
-
-
-#define FTS_MAX_APPENDABLE_HEIGHT 16
-
-/*
-** When full-text index nodes are loaded from disk, the buffer that they
-** are loaded into has the following number of bytes of padding at the end
-** of it. i.e. if a full-text index node is 900 bytes in size, then a buffer
-** of 920 bytes is allocated for it.
-**
-** This means that if we have a pointer into a buffer containing node data,
-** it is always safe to read up to two varints from it without risking an
-** overread, even if the node data is corrupted.
-*/
-#define FTS3_NODE_PADDING (FTS3_VARINT_MAX*2)
-
-/*
-** Under certain circumstances, b-tree nodes (doclists) can be loaded into
-** memory incrementally instead of all at once. This can be a big performance
-** win (reduced IO and CPU) if SQLite stops calling the virtual table xNext()
-** method before retrieving all query results (as may happen, for example,
-** if a query has a LIMIT clause).
-**
-** Incremental loading is used for b-tree nodes FTS3_NODE_CHUNK_THRESHOLD
-** bytes and larger. Nodes are loaded in chunks of FTS3_NODE_CHUNKSIZE bytes.
-** The code is written so that the hard lower-limit for each of these values
-** is 1. Clearly such small values would be inefficient, but can be useful
-** for testing purposes.
-**
-** If this module is built with SQLITE_TEST defined, these constants may
-** be overridden at runtime for testing purposes. File fts3_test.c contains
-** a Tcl interface to read and write the values.
-*/
-#ifdef SQLITE_TEST
-int test_fts3_node_chunksize = (4*1024);
-int test_fts3_node_chunk_threshold = (4*1024)*4;
-# define FTS3_NODE_CHUNKSIZE test_fts3_node_chunksize
-# define FTS3_NODE_CHUNK_THRESHOLD test_fts3_node_chunk_threshold
-#else
-# define FTS3_NODE_CHUNKSIZE (4*1024)
-# define FTS3_NODE_CHUNK_THRESHOLD (FTS3_NODE_CHUNKSIZE*4)
-#endif
-
-/*
-** The two values that may be meaningfully bound to the :1 parameter in
-** statements SQL_REPLACE_STAT and SQL_SELECT_STAT.
-*/
-#define FTS_STAT_DOCTOTAL 0
-#define FTS_STAT_INCRMERGEHINT 1
-#define FTS_STAT_AUTOINCRMERGE 2
-
-/*
-** If FTS_LOG_MERGES is defined, call sqlite3_log() to report each automatic
-** and incremental merge operation that takes place. This is used for
-** debugging FTS only, it should not usually be turned on in production
-** systems.
-*/
-#ifdef FTS3_LOG_MERGES
-static void fts3LogMerge(int nMerge, sqlite3_int64 iAbsLevel){
- sqlite3_log(SQLITE_OK, "%d-way merge from level %d", nMerge, (int)iAbsLevel);
-}
-#else
-#define fts3LogMerge(x, y)
-#endif
-
-
-typedef struct PendingList PendingList;
-typedef struct SegmentNode SegmentNode;
-typedef struct SegmentWriter SegmentWriter;
-
-/*
-** An instance of the following data structure is used to build doclists
-** incrementally. See function fts3PendingListAppend() for details.
-*/
-struct PendingList {
- int nData;
- char *aData;
- int nSpace;
- sqlite3_int64 iLastDocid;
- sqlite3_int64 iLastCol;
- sqlite3_int64 iLastPos;
-};
-
-
-/*
-** Each cursor has a (possibly empty) linked list of the following objects.
-*/
-struct Fts3DeferredToken {
- Fts3PhraseToken *pToken; /* Pointer to corresponding expr token */
- int iCol; /* Column token must occur in */
- Fts3DeferredToken *pNext; /* Next in list of deferred tokens */
- PendingList *pList; /* Doclist is assembled here */
-};
-
-/*
-** An instance of this structure is used to iterate through the terms on
-** a contiguous set of segment b-tree leaf nodes. Although the details of
-** this structure are only manipulated by code in this file, opaque handles
-** of type Fts3SegReader* are also used by code in fts3.c to iterate through
-** terms when querying the full-text index. See functions:
-**
-** sqlite3Fts3SegReaderNew()
-** sqlite3Fts3SegReaderFree()
-** sqlite3Fts3SegReaderIterate()
-**
-** Methods used to manipulate Fts3SegReader structures:
-**
-** fts3SegReaderNext()
-** fts3SegReaderFirstDocid()
-** fts3SegReaderNextDocid()
-*/
-struct Fts3SegReader {
- int iIdx; /* Index within level, or 0x7FFFFFFF for PT */
- u8 bLookup; /* True for a lookup only */
- u8 rootOnly; /* True for a root-only reader */
-
- sqlite3_int64 iStartBlock; /* Rowid of first leaf block to traverse */
- sqlite3_int64 iLeafEndBlock; /* Rowid of final leaf block to traverse */
- sqlite3_int64 iEndBlock; /* Rowid of final block in segment (or 0) */
- sqlite3_int64 iCurrentBlock; /* Current leaf block (or 0) */
-
- char *aNode; /* Pointer to node data (or NULL) */
- int nNode; /* Size of buffer at aNode (or 0) */
- int nPopulate; /* If >0, bytes of buffer aNode[] loaded */
- sqlite3_blob *pBlob; /* If not NULL, blob handle to read node */
-
- Fts3HashElem **ppNextElem;
-
- /* Variables set by fts3SegReaderNext(). These may be read directly
- ** by the caller. They are valid from the time SegmentReaderNew() returns
- ** until SegmentReaderNext() returns something other than SQLITE_OK
- ** (i.e. SQLITE_DONE).
- */
- int nTerm; /* Number of bytes in current term */
- char *zTerm; /* Pointer to current term */
- int nTermAlloc; /* Allocated size of zTerm buffer */
- char *aDoclist; /* Pointer to doclist of current entry */
- int nDoclist; /* Size of doclist in current entry */
-
- /* The following variables are used by fts3SegReaderNextDocid() to iterate
- ** through the current doclist (aDoclist/nDoclist).
- */
- char *pOffsetList;
- int nOffsetList; /* For descending pending seg-readers only */
- sqlite3_int64 iDocid;
-};
-
-#define fts3SegReaderIsPending(p) ((p)->ppNextElem!=0)
-#define fts3SegReaderIsRootOnly(p) ((p)->rootOnly!=0)
-
-/*
-** An instance of this structure is used to create a segment b-tree in the
-** database. The internal details of this type are only accessed by the
-** following functions:
-**
-** fts3SegWriterAdd()
-** fts3SegWriterFlush()
-** fts3SegWriterFree()
-*/
-struct SegmentWriter {
- SegmentNode *pTree; /* Pointer to interior tree structure */
- sqlite3_int64 iFirst; /* First slot in %_segments written */
- sqlite3_int64 iFree; /* Next free slot in %_segments */
- char *zTerm; /* Pointer to previous term buffer */
- int nTerm; /* Number of bytes in zTerm */
- int nMalloc; /* Size of malloc'd buffer at zMalloc */
- char *zMalloc; /* Malloc'd space (possibly) used for zTerm */
- int nSize; /* Size of allocation at aData */
- int nData; /* Bytes of data in aData */
- char *aData; /* Pointer to block from malloc() */
- i64 nLeafData; /* Number of bytes of leaf data written */
-};
-
-/*
-** Type SegmentNode is used by the following three functions to create
-** the interior part of the segment b+-tree structures (everything except
-** the leaf nodes). These functions and type are only ever used by code
-** within the fts3SegWriterXXX() family of functions described above.
-**
-** fts3NodeAddTerm()
-** fts3NodeWrite()
-** fts3NodeFree()
-**
-** When a b+tree is written to the database (either as a result of a merge
-** or the pending-terms table being flushed), leaves are written into the
-** database file as soon as they are completely populated. The interior of
-** the tree is assembled in memory and written out only once all leaves have
-** been populated and stored. This is Ok, as the b+-tree fanout is usually
-** very large, meaning that the interior of the tree consumes relatively
-** little memory.
-*/
-struct SegmentNode {
- SegmentNode *pParent; /* Parent node (or NULL for root node) */
- SegmentNode *pRight; /* Pointer to right-sibling */
- SegmentNode *pLeftmost; /* Pointer to left-most node of this depth */
- int nEntry; /* Number of terms written to node so far */
- char *zTerm; /* Pointer to previous term buffer */
- int nTerm; /* Number of bytes in zTerm */
- int nMalloc; /* Size of malloc'd buffer at zMalloc */
- char *zMalloc; /* Malloc'd space (possibly) used for zTerm */
- int nData; /* Bytes of valid data so far */
- char *aData; /* Node data */
-};
-
-/*
-** Valid values for the second argument to fts3SqlStmt().
-*/
-#define SQL_DELETE_CONTENT 0
-#define SQL_IS_EMPTY 1
-#define SQL_DELETE_ALL_CONTENT 2
-#define SQL_DELETE_ALL_SEGMENTS 3
-#define SQL_DELETE_ALL_SEGDIR 4
-#define SQL_DELETE_ALL_DOCSIZE 5
-#define SQL_DELETE_ALL_STAT 6
-#define SQL_SELECT_CONTENT_BY_ROWID 7
-#define SQL_NEXT_SEGMENT_INDEX 8
-#define SQL_INSERT_SEGMENTS 9
-#define SQL_NEXT_SEGMENTS_ID 10
-#define SQL_INSERT_SEGDIR 11
-#define SQL_SELECT_LEVEL 12
-#define SQL_SELECT_LEVEL_RANGE 13
-#define SQL_SELECT_LEVEL_COUNT 14
-#define SQL_SELECT_SEGDIR_MAX_LEVEL 15
-#define SQL_DELETE_SEGDIR_LEVEL 16
-#define SQL_DELETE_SEGMENTS_RANGE 17
-#define SQL_CONTENT_INSERT 18
-#define SQL_DELETE_DOCSIZE 19
-#define SQL_REPLACE_DOCSIZE 20
-#define SQL_SELECT_DOCSIZE 21
-#define SQL_SELECT_STAT 22
-#define SQL_REPLACE_STAT 23
-
-#define SQL_SELECT_ALL_PREFIX_LEVEL 24
-#define SQL_DELETE_ALL_TERMS_SEGDIR 25
-#define SQL_DELETE_SEGDIR_RANGE 26
-#define SQL_SELECT_ALL_LANGID 27
-#define SQL_FIND_MERGE_LEVEL 28
-#define SQL_MAX_LEAF_NODE_ESTIMATE 29
-#define SQL_DELETE_SEGDIR_ENTRY 30
-#define SQL_SHIFT_SEGDIR_ENTRY 31
-#define SQL_SELECT_SEGDIR 32
-#define SQL_CHOMP_SEGDIR 33
-#define SQL_SEGMENT_IS_APPENDABLE 34
-#define SQL_SELECT_INDEXES 35
-#define SQL_SELECT_MXLEVEL 36
-
-#define SQL_SELECT_LEVEL_RANGE2 37
-#define SQL_UPDATE_LEVEL_IDX 38
-#define SQL_UPDATE_LEVEL 39
-
-/*
-** This function is used to obtain an SQLite prepared statement handle
-** for the statement identified by the second argument. If successful,
-** *pp is set to the requested statement handle and SQLITE_OK returned.
-** Otherwise, an SQLite error code is returned and *pp is set to 0.
-**
-** If argument apVal is not NULL, then it must point to an array with
-** at least as many entries as the requested statement has bound
-** parameters. The values are bound to the statements parameters before
-** returning.
-*/
-static int fts3SqlStmt(
- Fts3Table *p, /* Virtual table handle */
- int eStmt, /* One of the SQL_XXX constants above */
- sqlite3_stmt **pp, /* OUT: Statement handle */
- sqlite3_value **apVal /* Values to bind to statement */
-){
- const char *azSql[] = {
-/* 0 */ "DELETE FROM %Q.'%q_content' WHERE rowid = ?",
-/* 1 */ "SELECT NOT EXISTS(SELECT docid FROM %Q.'%q_content' WHERE rowid!=?)",
-/* 2 */ "DELETE FROM %Q.'%q_content'",
-/* 3 */ "DELETE FROM %Q.'%q_segments'",
-/* 4 */ "DELETE FROM %Q.'%q_segdir'",
-/* 5 */ "DELETE FROM %Q.'%q_docsize'",
-/* 6 */ "DELETE FROM %Q.'%q_stat'",
-/* 7 */ "SELECT %s WHERE rowid=?",
-/* 8 */ "SELECT (SELECT max(idx) FROM %Q.'%q_segdir' WHERE level = ?) + 1",
-/* 9 */ "REPLACE INTO %Q.'%q_segments'(blockid, block) VALUES(?, ?)",
-/* 10 */ "SELECT coalesce((SELECT max(blockid) FROM %Q.'%q_segments') + 1, 1)",
-/* 11 */ "REPLACE INTO %Q.'%q_segdir' VALUES(?,?,?,?,?,?)",
-
- /* Return segments in order from oldest to newest.*/
-/* 12 */ "SELECT idx, start_block, leaves_end_block, end_block, root "
- "FROM %Q.'%q_segdir' WHERE level = ? ORDER BY idx ASC",
-/* 13 */ "SELECT idx, start_block, leaves_end_block, end_block, root "
- "FROM %Q.'%q_segdir' WHERE level BETWEEN ? AND ?"
- "ORDER BY level DESC, idx ASC",
-
-/* 14 */ "SELECT count(*) FROM %Q.'%q_segdir' WHERE level = ?",
-/* 15 */ "SELECT max(level) FROM %Q.'%q_segdir' WHERE level BETWEEN ? AND ?",
-
-/* 16 */ "DELETE FROM %Q.'%q_segdir' WHERE level = ?",
-/* 17 */ "DELETE FROM %Q.'%q_segments' WHERE blockid BETWEEN ? AND ?",
-/* 18 */ "INSERT INTO %Q.'%q_content' VALUES(%s)",
-/* 19 */ "DELETE FROM %Q.'%q_docsize' WHERE docid = ?",
-/* 20 */ "REPLACE INTO %Q.'%q_docsize' VALUES(?,?)",
-/* 21 */ "SELECT size FROM %Q.'%q_docsize' WHERE docid=?",
-/* 22 */ "SELECT value FROM %Q.'%q_stat' WHERE id=?",
-/* 23 */ "REPLACE INTO %Q.'%q_stat' VALUES(?,?)",
-/* 24 */ "",
-/* 25 */ "",
-
-/* 26 */ "DELETE FROM %Q.'%q_segdir' WHERE level BETWEEN ? AND ?",
-/* 27 */ "SELECT DISTINCT level / (1024 * ?) FROM %Q.'%q_segdir'",
-
-/* This statement is used to determine which level to read the input from
-** when performing an incremental merge. It returns the absolute level number
-** of the oldest level in the db that contains at least ? segments. Or,
-** if no level in the FTS index contains more than ? segments, the statement
-** returns zero rows. */
-/* 28 */ "SELECT level FROM %Q.'%q_segdir' GROUP BY level HAVING count(*)>=?"
- " ORDER BY (level %% 1024) ASC LIMIT 1",
-
-/* Estimate the upper limit on the number of leaf nodes in a new segment
-** created by merging the oldest :2 segments from absolute level :1. See
-** function sqlite3Fts3Incrmerge() for details. */
-/* 29 */ "SELECT 2 * total(1 + leaves_end_block - start_block) "
- " FROM %Q.'%q_segdir' WHERE level = ? AND idx < ?",
-
-/* SQL_DELETE_SEGDIR_ENTRY
-** Delete the %_segdir entry on absolute level :1 with index :2. */
-/* 30 */ "DELETE FROM %Q.'%q_segdir' WHERE level = ? AND idx = ?",
-
-/* SQL_SHIFT_SEGDIR_ENTRY
-** Modify the idx value for the segment with idx=:3 on absolute level :2
-** to :1. */
-/* 31 */ "UPDATE %Q.'%q_segdir' SET idx = ? WHERE level=? AND idx=?",
-
-/* SQL_SELECT_SEGDIR
-** Read a single entry from the %_segdir table. The entry from absolute
-** level :1 with index value :2. */
-/* 32 */ "SELECT idx, start_block, leaves_end_block, end_block, root "
- "FROM %Q.'%q_segdir' WHERE level = ? AND idx = ?",
-
-/* SQL_CHOMP_SEGDIR
-** Update the start_block (:1) and root (:2) fields of the %_segdir
-** entry located on absolute level :3 with index :4. */
-/* 33 */ "UPDATE %Q.'%q_segdir' SET start_block = ?, root = ?"
- "WHERE level = ? AND idx = ?",
-
-/* SQL_SEGMENT_IS_APPENDABLE
-** Return a single row if the segment with end_block=? is appendable. Or
-** no rows otherwise. */
-/* 34 */ "SELECT 1 FROM %Q.'%q_segments' WHERE blockid=? AND block IS NULL",
-
-/* SQL_SELECT_INDEXES
-** Return the list of valid segment indexes for absolute level ? */
-/* 35 */ "SELECT idx FROM %Q.'%q_segdir' WHERE level=? ORDER BY 1 ASC",
-
-/* SQL_SELECT_MXLEVEL
-** Return the largest relative level in the FTS index or indexes. */
-/* 36 */ "SELECT max( level %% 1024 ) FROM %Q.'%q_segdir'",
-
- /* Return segments in order from oldest to newest.*/
-/* 37 */ "SELECT level, idx, end_block "
- "FROM %Q.'%q_segdir' WHERE level BETWEEN ? AND ? "
- "ORDER BY level DESC, idx ASC",
-
- /* Update statements used while promoting segments */
-/* 38 */ "UPDATE OR FAIL %Q.'%q_segdir' SET level=-1,idx=? "
- "WHERE level=? AND idx=?",
-/* 39 */ "UPDATE OR FAIL %Q.'%q_segdir' SET level=? WHERE level=-1"
-
- };
- int rc = SQLITE_OK;
- sqlite3_stmt *pStmt;
-
- assert( SizeofArray(azSql)==SizeofArray(p->aStmt) );
- assert( eStmt<SizeofArray(azSql) && eStmt>=0 );
-
- pStmt = p->aStmt[eStmt];
- if( !pStmt ){
- char *zSql;
- if( eStmt==SQL_CONTENT_INSERT ){
- zSql = sqlite3_mprintf(azSql[eStmt], p->zDb, p->zName, p->zWriteExprlist);
- }else if( eStmt==SQL_SELECT_CONTENT_BY_ROWID ){
- zSql = sqlite3_mprintf(azSql[eStmt], p->zReadExprlist);
- }else{
- zSql = sqlite3_mprintf(azSql[eStmt], p->zDb, p->zName);
- }
- if( !zSql ){
- rc = SQLITE_NOMEM;
- }else{
- rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, NULL);
- sqlite3_free(zSql);
- assert( rc==SQLITE_OK || pStmt==0 );
- p->aStmt[eStmt] = pStmt;
- }
- }
- if( apVal ){
- int i;
- int nParam = sqlite3_bind_parameter_count(pStmt);
- for(i=0; rc==SQLITE_OK && i<nParam; i++){
- rc = sqlite3_bind_value(pStmt, i+1, apVal[i]);
- }
- }
- *pp = pStmt;
- return rc;
-}
-
-
-static int fts3SelectDocsize(
- Fts3Table *pTab, /* FTS3 table handle */
- sqlite3_int64 iDocid, /* Docid to bind for SQL_SELECT_DOCSIZE */
- sqlite3_stmt **ppStmt /* OUT: Statement handle */
-){
- sqlite3_stmt *pStmt = 0; /* Statement requested from fts3SqlStmt() */
- int rc; /* Return code */
-
- rc = fts3SqlStmt(pTab, SQL_SELECT_DOCSIZE, &pStmt, 0);
- if( rc==SQLITE_OK ){
- 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;
- return rc;
-}
-
-int sqlite3Fts3SelectDoctotal(
- Fts3Table *pTab, /* Fts3 table handle */
- sqlite3_stmt **ppStmt /* OUT: Statement handle */
-){
- sqlite3_stmt *pStmt = 0;
- int rc;
- rc = fts3SqlStmt(pTab, SQL_SELECT_STAT, &pStmt, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int(pStmt, 1, FTS_STAT_DOCTOTAL);
- if( sqlite3_step(pStmt)!=SQLITE_ROW
- || sqlite3_column_type(pStmt, 0)!=SQLITE_BLOB
- ){
- rc = sqlite3_reset(pStmt);
- if( rc==SQLITE_OK ) rc = FTS_CORRUPT_VTAB;
- pStmt = 0;
- }
- }
- *ppStmt = pStmt;
- return rc;
-}
-
-int sqlite3Fts3SelectDocsize(
- Fts3Table *pTab, /* Fts3 table handle */
- sqlite3_int64 iDocid, /* Docid to read size data for */
- sqlite3_stmt **ppStmt /* OUT: Statement handle */
-){
- return fts3SelectDocsize(pTab, iDocid, ppStmt);
-}
-
-/*
-** Similar to fts3SqlStmt(). Except, after binding the parameters in
-** array apVal[] to the SQL statement identified by eStmt, the statement
-** is executed.
-**
-** Returns SQLITE_OK if the statement is successfully executed, or an
-** SQLite error code otherwise.
-*/
-static void fts3SqlExec(
- int *pRC, /* Result code */
- Fts3Table *p, /* The FTS3 table */
- int eStmt, /* Index of statement to evaluate */
- sqlite3_value **apVal /* Parameters to bind */
-){
- sqlite3_stmt *pStmt;
- int rc;
- if( *pRC ) return;
- rc = fts3SqlStmt(p, eStmt, &pStmt, apVal);
- if( rc==SQLITE_OK ){
- sqlite3_step(pStmt);
- rc = sqlite3_reset(pStmt);
- }
- *pRC = rc;
-}
-
-
-/*
-** This function ensures that the caller has obtained an exclusive
-** shared-cache table-lock on the %_segdir table. This is required before
-** writing data to the fts3 table. If this lock is not acquired first, then
-** the caller may end up attempting to take this lock as part of committing
-** a transaction, causing SQLite to return SQLITE_LOCKED or
-** LOCKED_SHAREDCACHEto a COMMIT command.
-**
-** It is best to avoid this because if FTS3 returns any error when
-** committing a transaction, the whole transaction will be rolled back.
-** And this is not what users expect when they get SQLITE_LOCKED_SHAREDCACHE.
-** It can still happen if the user locks the underlying tables directly
-** instead of accessing them via FTS.
-*/
-static int fts3Writelock(Fts3Table *p){
- int rc = SQLITE_OK;
-
- if( p->nPendingData==0 ){
- sqlite3_stmt *pStmt;
- rc = fts3SqlStmt(p, SQL_DELETE_SEGDIR_LEVEL, &pStmt, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_null(pStmt, 1);
- sqlite3_step(pStmt);
- rc = sqlite3_reset(pStmt);
- }
- }
-
- 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, /* FTS3 table handle */
- int iLangid, /* Language id */
- int iIndex, /* Index in p->aIndex[] */
- int iLevel /* Level of segments */
-){
- 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,
-** return an SQLite error code.
-**
-** There is only ever one instance of this SQL statement compiled for
-** each FTS3 table.
-**
-** The statement returns the following columns from the %_segdir table:
-**
-** 0: idx
-** 1: start_block
-** 2: leaves_end_block
-** 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;
-}
-
-
-/*
-** Append a single varint to a PendingList buffer. SQLITE_OK is returned
-** if successful, or an SQLite error code otherwise.
-**
-** This function also serves to allocate the PendingList structure itself.
-** For example, to create a new PendingList structure containing two
-** varints:
-**
-** PendingList *p = 0;
-** fts3PendingListAppendVarint(&p, 1);
-** fts3PendingListAppendVarint(&p, 2);
-*/
-static int fts3PendingListAppendVarint(
- PendingList **pp, /* IN/OUT: Pointer to PendingList struct */
- sqlite3_int64 i /* Value to append to data */
-){
- PendingList *p = *pp;
-
- /* Allocate or grow the PendingList as required. */
- if( !p ){
- p = sqlite3_malloc(sizeof(*p) + 100);
- if( !p ){
- return SQLITE_NOMEM;
- }
- p->nSpace = 100;
- p->aData = (char *)&p[1];
- p->nData = 0;
- }
- else if( p->nData+FTS3_VARINT_MAX+1>p->nSpace ){
- int nNew = p->nSpace * 2;
- p = sqlite3_realloc(p, sizeof(*p) + nNew);
- if( !p ){
- sqlite3_free(*pp);
- *pp = 0;
- return SQLITE_NOMEM;
- }
- p->nSpace = nNew;
- p->aData = (char *)&p[1];
- }
-
- /* Append the new serialized varint to the end of the list. */
- p->nData += sqlite3Fts3PutVarint(&p->aData[p->nData], i);
- p->aData[p->nData] = '\0';
- *pp = p;
- return SQLITE_OK;
-}
-
-/*
-** Add a docid/column/position entry to a PendingList structure. Non-zero
-** is returned if the structure is sqlite3_realloced as part of adding
-** the entry. Otherwise, zero.
-**
-** If an OOM error occurs, *pRc is set to SQLITE_NOMEM before returning.
-** Zero is always returned in this case. Otherwise, if no OOM error occurs,
-** it is set to SQLITE_OK.
-*/
-static int fts3PendingListAppend(
- PendingList **pp, /* IN/OUT: PendingList structure */
- sqlite3_int64 iDocid, /* Docid for entry to add */
- sqlite3_int64 iCol, /* Column for entry to add */
- sqlite3_int64 iPos, /* Position of term for entry to add */
- int *pRc /* OUT: Return code */
-){
- PendingList *p = *pp;
- int rc = SQLITE_OK;
-
- assert( !p || p->iLastDocid<=iDocid );
-
- if( !p || p->iLastDocid!=iDocid ){
- sqlite3_int64 iDelta = iDocid - (p ? p->iLastDocid : 0);
- if( p ){
- assert( p->nData<p->nSpace );
- assert( p->aData[p->nData]==0 );
- p->nData++;
- }
- if( SQLITE_OK!=(rc = fts3PendingListAppendVarint(&p, iDelta)) ){
- goto pendinglistappend_out;
- }
- p->iLastCol = -1;
- p->iLastPos = 0;
- p->iLastDocid = iDocid;
- }
- if( iCol>0 && p->iLastCol!=iCol ){
- if( SQLITE_OK!=(rc = fts3PendingListAppendVarint(&p, 1))
- || SQLITE_OK!=(rc = fts3PendingListAppendVarint(&p, iCol))
- ){
- goto pendinglistappend_out;
- }
- p->iLastCol = iCol;
- p->iLastPos = 0;
- }
- if( iCol>=0 ){
- assert( iPos>p->iLastPos || (iPos==0 && p->iLastPos==0) );
- rc = fts3PendingListAppendVarint(&p, 2+iPos-p->iLastPos);
- if( rc==SQLITE_OK ){
- p->iLastPos = iPos;
- }
- }
-
- pendinglistappend_out:
- *pRc = rc;
- if( p!=*pp ){
- *pp = p;
- return 1;
- }
- return 0;
-}
-
-/*
-** Free a PendingList object allocated by fts3PendingListAppend().
-*/
-static void fts3PendingListDelete(PendingList *pList){
- sqlite3_free(pList);
-}
-
-/*
-** Add an entry to one of the pending-terms hash tables.
-*/
-static int fts3PendingTermsAddOne(
- Fts3Table *p,
- int iCol,
- int iPos,
- Fts3Hash *pHash, /* Pending terms hash table to add entry to */
- const char *zToken,
- int nToken
-){
- PendingList *pList;
- int rc = SQLITE_OK;
-
- pList = (PendingList *)fts3HashFind(pHash, zToken, nToken);
- if( pList ){
- p->nPendingData -= (pList->nData + nToken + sizeof(Fts3HashElem));
- }
- if( fts3PendingListAppend(&pList, p->iPrevDocid, iCol, iPos, &rc) ){
- if( pList==fts3HashInsert(pHash, zToken, nToken, pList) ){
- /* Malloc failed while inserting the new entry. This can only
- ** happen if there was no previous entry for this token.
- */
- assert( 0==fts3HashFind(pHash, zToken, nToken) );
- sqlite3_free(pList);
- rc = SQLITE_NOMEM;
- }
- }
- if( rc==SQLITE_OK ){
- p->nPendingData += (pList->nData + nToken + sizeof(Fts3HashElem));
- }
- return rc;
-}
-
-/*
-** Tokenize the nul-terminated string zText and add all tokens to the
-** pending-terms hash-table. The docid used is that currently stored in
-** p->iPrevDocid, and the column is specified by argument iCol.
-**
-** If successful, SQLITE_OK is returned. Otherwise, an SQLite error code.
-*/
-static int fts3PendingTermsAdd(
- Fts3Table *p, /* Table into which text will be inserted */
- int iLangid, /* Language id to use */
- const char *zText, /* Text of document to be inserted */
- int iCol, /* Column into which text is being inserted */
- u32 *pnWord /* IN/OUT: Incr. by number tokens inserted */
-){
- int rc;
- int iStart = 0;
- int iEnd = 0;
- int iPos = 0;
- int nWord = 0;
-
- char const *zToken;
- int nToken = 0;
-
- sqlite3_tokenizer *pTokenizer = p->pTokenizer;
- sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
- sqlite3_tokenizer_cursor *pCsr;
- int (*xNext)(sqlite3_tokenizer_cursor *pCursor,
- const char**,int*,int*,int*,int*);
-
- assert( pTokenizer && pModule );
-
- /* If the user has inserted a NULL value, this function may be called with
- ** zText==0. In this case, add zero token entries to the hash table and
- ** return early. */
- if( zText==0 ){
- *pnWord = 0;
- return SQLITE_OK;
- }
-
- rc = sqlite3Fts3OpenTokenizer(pTokenizer, iLangid, zText, -1, &pCsr);
- if( rc!=SQLITE_OK ){
- return rc;
- }
-
- xNext = pModule->xNext;
- while( SQLITE_OK==rc
- && SQLITE_OK==(rc = xNext(pCsr, &zToken, &nToken, &iStart, &iEnd, &iPos))
- ){
- int i;
- if( iPos>=nWord ) nWord = iPos+1;
-
- /* Positions cannot be negative; we use -1 as a terminator internally.
- ** Tokens must have a non-zero length.
- */
- if( iPos<0 || !zToken || nToken<=0 ){
- rc = SQLITE_ERROR;
- break;
- }
-
- /* Add the term to the terms index */
- rc = fts3PendingTermsAddOne(
- p, iCol, iPos, &p->aIndex[0].hPending, zToken, nToken
- );
-
- /* Add the term to each of the prefix indexes that it is not too
- ** short for. */
- for(i=1; rc==SQLITE_OK && i<p->nIndex; i++){
- struct Fts3Index *pIndex = &p->aIndex[i];
- if( nToken<pIndex->nPrefix ) continue;
- rc = fts3PendingTermsAddOne(
- p, iCol, iPos, &pIndex->hPending, zToken, pIndex->nPrefix
- );
- }
- }
-
- pModule->xClose(pCsr);
- *pnWord += nWord;
- return (rc==SQLITE_DONE ? SQLITE_OK : rc);
-}
-
-/*
-** Calling this function indicates that subsequent calls to
-** fts3PendingTermsAdd() are to add term/position-list pairs for the
-** contents of the document with docid iDocid.
-*/
-static int fts3PendingTermsDocid(
- Fts3Table *p, /* Full-text table handle */
- int iLangid, /* Language id of row being written */
- sqlite_int64 iDocid /* Docid of row being written */
-){
- assert( iLangid>=0 );
-
- /* TODO(shess) Explore whether partially flushing the buffer on
- ** forced-flush would provide better performance. I suspect that if
- ** we ordered the doclists by size and flushed the largest until the
- ** buffer was half empty, that would let the less frequent terms
- ** generate longer doclists.
- */
- if( iDocid<=p->iPrevDocid
- || p->iPrevLangid!=iLangid
- || p->nPendingData>p->nMaxPendingData
- ){
- int rc = sqlite3Fts3PendingTermsFlush(p);
- if( rc!=SQLITE_OK ) return rc;
- }
- p->iPrevDocid = iDocid;
- p->iPrevLangid = iLangid;
- return SQLITE_OK;
-}
-
-/*
-** Discard the contents of the pending-terms hash tables.
-*/
-void sqlite3Fts3PendingTermsClear(Fts3Table *p){
- int i;
- for(i=0; i<p->nIndex; i++){
- Fts3HashElem *pElem;
- Fts3Hash *pHash = &p->aIndex[i].hPending;
- for(pElem=fts3HashFirst(pHash); pElem; pElem=fts3HashNext(pElem)){
- PendingList *pList = (PendingList *)fts3HashData(pElem);
- fts3PendingListDelete(pList);
- }
- fts3HashClear(pHash);
- }
- p->nPendingData = 0;
-}
-
-/*
-** This function is called by the xUpdate() method as part of an INSERT
-** operation. It adds entries for each term in the new record to the
-** pendingTerms hash table.
-**
-** Argument apVal is the same as the similarly named argument passed to
-** fts3InsertData(). Parameter iDocid is the docid of the new row.
-*/
-static int fts3InsertTerms(
- Fts3Table *p,
- int iLangid,
- sqlite3_value **apVal,
- u32 *aSz
-){
- int i; /* Iterator variable */
- for(i=2; i<p->nColumn+2; i++){
- int iCol = i-2;
- if( p->abNotindexed[iCol]==0 ){
- const char *zText = (const char *)sqlite3_value_text(apVal[i]);
- int rc = fts3PendingTermsAdd(p, iLangid, zText, iCol, &aSz[iCol]);
- if( rc!=SQLITE_OK ){
- return rc;
- }
- aSz[p->nColumn] += sqlite3_value_bytes(apVal[i]);
- }
- }
- return SQLITE_OK;
-}
-
-/*
-** This function is called by the xUpdate() method for an INSERT operation.
-** The apVal parameter is passed a copy of the apVal argument passed by
-** SQLite to the xUpdate() method. i.e:
-**
-** apVal[0] Not used for INSERT.
-** apVal[1] rowid
-** apVal[2] Left-most user-defined column
-** ...
-** apVal[p->nColumn+1] Right-most user-defined column
-** apVal[p->nColumn+2] Hidden column with same name as table
-** apVal[p->nColumn+3] Hidden "docid" column (alias for rowid)
-** apVal[p->nColumn+4] Hidden languageid column
-*/
-static int fts3InsertData(
- Fts3Table *p, /* Full-text table */
- sqlite3_value **apVal, /* Array of values to insert */
- sqlite3_int64 *piDocid /* OUT: Docid for row just inserted */
-){
- int rc; /* Return code */
- sqlite3_stmt *pContentInsert; /* INSERT INTO %_content VALUES(...) */
-
- if( p->zContentTbl ){
- sqlite3_value *pRowid = apVal[p->nColumn+3];
- if( sqlite3_value_type(pRowid)==SQLITE_NULL ){
- pRowid = apVal[1];
- }
- if( sqlite3_value_type(pRowid)!=SQLITE_INTEGER ){
- return SQLITE_CONSTRAINT;
- }
- *piDocid = sqlite3_value_int64(pRowid);
- return SQLITE_OK;
- }
-
- /* Locate the statement handle used to insert data into the %_content
- ** table. The SQL for this statement is:
- **
- ** INSERT INTO %_content VALUES(?, ?, ?, ...)
- **
- ** The statement features N '?' variables, where N is the number of user
- ** defined columns in the FTS3 table, plus one for the docid field.
- */
- rc = fts3SqlStmt(p, SQL_CONTENT_INSERT, &pContentInsert, &apVal[1]);
- if( rc==SQLITE_OK && p->zLanguageid ){
- rc = sqlite3_bind_int(
- pContentInsert, p->nColumn+2,
- sqlite3_value_int(apVal[p->nColumn+4])
- );
- }
- if( rc!=SQLITE_OK ) return rc;
-
- /* There is a quirk here. The users INSERT statement may have specified
- ** a value for the "rowid" field, for the "docid" field, or for both.
- ** Which is a problem, since "rowid" and "docid" are aliases for the
- ** same value. For example:
- **
- ** INSERT INTO fts3tbl(rowid, docid) VALUES(1, 2);
- **
- ** In FTS3, this is an error. It is an error to specify non-NULL values
- ** for both docid and some other rowid alias.
- */
- if( SQLITE_NULL!=sqlite3_value_type(apVal[3+p->nColumn]) ){
- if( SQLITE_NULL==sqlite3_value_type(apVal[0])
- && SQLITE_NULL!=sqlite3_value_type(apVal[1])
- ){
- /* A rowid/docid conflict. */
- return SQLITE_ERROR;
- }
- rc = sqlite3_bind_value(pContentInsert, 1, apVal[3+p->nColumn]);
- if( rc!=SQLITE_OK ) return rc;
- }
-
- /* Execute the statement to insert the record. Set *piDocid to the
- ** new docid value.
- */
- sqlite3_step(pContentInsert);
- rc = sqlite3_reset(pContentInsert);
-
- *piDocid = sqlite3_last_insert_rowid(p->db);
- return rc;
-}
-
-
-
-/*
-** Remove all data from the FTS3 table. Clear the hash table containing
-** pending terms.
-*/
-static int fts3DeleteAll(Fts3Table *p, int bContent){
- int rc = SQLITE_OK; /* Return code */
-
- /* Discard the contents of the pending-terms hash table. */
- sqlite3Fts3PendingTermsClear(p);
-
- /* Delete everything from the shadow tables. Except, leave %_content as
- ** is if bContent is false. */
- assert( p->zContentTbl==0 || bContent==0 );
- if( bContent ) fts3SqlExec(&rc, p, SQL_DELETE_ALL_CONTENT, 0);
- fts3SqlExec(&rc, p, SQL_DELETE_ALL_SEGMENTS, 0);
- fts3SqlExec(&rc, p, SQL_DELETE_ALL_SEGDIR, 0);
- if( p->bHasDocsize ){
- fts3SqlExec(&rc, p, SQL_DELETE_ALL_DOCSIZE, 0);
- }
- if( p->bHasStat ){
- fts3SqlExec(&rc, p, SQL_DELETE_ALL_STAT, 0);
- }
- return rc;
-}
-
-/*
-**
-*/
-static int langidFromSelect(Fts3Table *p, sqlite3_stmt *pSelect){
- int iLangid = 0;
- if( p->zLanguageid ) iLangid = sqlite3_column_int(pSelect, p->nColumn+1);
- return iLangid;
-}
-
-/*
-** The first element in the apVal[] array is assumed to contain the docid
-** (an integer) of a row about to be deleted. Remove all terms from the
-** full-text index.
-*/
-static void fts3DeleteTerms(
- int *pRC, /* Result code */
- Fts3Table *p, /* The FTS table to delete from */
- sqlite3_value *pRowid, /* The docid to be deleted */
- u32 *aSz, /* Sizes of deleted document written here */
- int *pbFound /* OUT: Set to true if row really does exist */
-){
- int rc;
- sqlite3_stmt *pSelect;
-
- assert( *pbFound==0 );
- if( *pRC ) return;
- rc = fts3SqlStmt(p, SQL_SELECT_CONTENT_BY_ROWID, &pSelect, &pRowid);
- if( rc==SQLITE_OK ){
- if( SQLITE_ROW==sqlite3_step(pSelect) ){
- int i;
- int iLangid = langidFromSelect(p, pSelect);
- rc = fts3PendingTermsDocid(p, iLangid, sqlite3_column_int64(pSelect, 0));
- for(i=1; rc==SQLITE_OK && i<=p->nColumn; i++){
- int iCol = i-1;
- if( p->abNotindexed[iCol]==0 ){
- const char *zText = (const char *)sqlite3_column_text(pSelect, i);
- rc = fts3PendingTermsAdd(p, iLangid, zText, -1, &aSz[iCol]);
- aSz[p->nColumn] += sqlite3_column_bytes(pSelect, i);
- }
- }
- if( rc!=SQLITE_OK ){
- sqlite3_reset(pSelect);
- *pRC = rc;
- return;
- }
- *pbFound = 1;
- }
- rc = sqlite3_reset(pSelect);
- }else{
- sqlite3_reset(pSelect);
- }
- *pRC = rc;
-}
-
-/*
-** Forward declaration to account for the circular dependency between
-** functions fts3SegmentMerge() and fts3AllocateSegdirIdx().
-*/
-static int fts3SegmentMerge(Fts3Table *, int, int, int);
-
-/*
-** This function allocates a new level iLevel index in the segdir table.
-** Usually, indexes are allocated within a level sequentially starting
-** with 0, so the allocated index is one greater than the value returned
-** by:
-**
-** SELECT max(idx) FROM %_segdir WHERE level = :iLevel
-**
-** However, if there are already FTS3_MERGE_COUNT indexes at the requested
-** level, they are merged into a single level (iLevel+1) segment and the
-** allocated index is 0.
-**
-** If successful, *piIdx is set to the allocated index slot and SQLITE_OK
-** returned. Otherwise, an SQLite error code is returned.
-*/
-static int fts3AllocateSegdirIdx(
- Fts3Table *p,
- int iLangid, /* Language id */
- int iIndex, /* Index for p->aIndex */
- int iLevel,
- int *piIdx
-){
- int rc; /* Return Code */
- sqlite3_stmt *pNextIdx; /* Query for next idx at level iLevel */
- int iNext = 0; /* Result of query pNextIdx */
-
- assert( iLangid>=0 );
- assert( p->nIndex>=1 );
-
- /* Set variable iNext to the next available segdir index at level iLevel. */
- rc = fts3SqlStmt(p, SQL_NEXT_SEGMENT_INDEX, &pNextIdx, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(
- pNextIdx, 1, getAbsoluteLevel(p, iLangid, iIndex, iLevel)
- );
- if( SQLITE_ROW==sqlite3_step(pNextIdx) ){
- iNext = sqlite3_column_int(pNextIdx, 0);
- }
- rc = sqlite3_reset(pNextIdx);
- }
-
- if( rc==SQLITE_OK ){
- /* If iNext is FTS3_MERGE_COUNT, indicating that level iLevel is already
- ** full, merge all segments in level iLevel into a single iLevel+1
- ** segment and allocate (newly freed) index 0 at level iLevel. Otherwise,
- ** if iNext is less than FTS3_MERGE_COUNT, allocate index iNext.
- */
- if( iNext>=FTS3_MERGE_COUNT ){
- fts3LogMerge(16, getAbsoluteLevel(p, iLangid, iIndex, iLevel));
- rc = fts3SegmentMerge(p, iLangid, iIndex, iLevel);
- *piIdx = 0;
- }else{
- *piIdx = iNext;
- }
- }
-
- return rc;
-}
-
-/*
-** The %_segments table is declared as follows:
-**
-** CREATE TABLE %_segments(blockid INTEGER PRIMARY KEY, block BLOB)
-**
-** This function reads data from a single row of the %_segments table. The
-** specific row is identified by the iBlockid parameter. If paBlob is not
-** NULL, then a buffer is allocated using sqlite3_malloc() and populated
-** with the contents of the blob stored in the "block" column of the
-** identified table row is. Whether or not paBlob is NULL, *pnBlob is set
-** to the size of the blob in bytes before returning.
-**
-** If an error occurs, or the table does not contain the specified row,
-** an SQLite error code is returned. Otherwise, SQLITE_OK is returned. If
-** paBlob is non-NULL, then it is the responsibility of the caller to
-** eventually free the returned buffer.
-**
-** This function may leave an open sqlite3_blob* handle in the
-** Fts3Table.pSegments variable. This handle is reused by subsequent calls
-** to this function. The handle may be closed by calling the
-** sqlite3Fts3SegmentsClose() function. Reusing a blob handle is a handy
-** performance improvement, but the blob handle should always be closed
-** before control is returned to the user (to prevent a lock being held
-** on the database file for longer than necessary). Thus, any virtual table
-** method (xFilter etc.) that may directly or indirectly call this function
-** must call sqlite3Fts3SegmentsClose() before returning.
-*/
-int sqlite3Fts3ReadBlock(
- Fts3Table *p, /* FTS3 table handle */
- sqlite3_int64 iBlockid, /* Access the row with blockid=$iBlockid */
- char **paBlob, /* OUT: Blob data in malloc'd buffer */
- int *pnBlob, /* OUT: Size of blob data */
- int *pnLoad /* OUT: Bytes actually loaded */
-){
- int rc; /* Return code */
-
- /* pnBlob must be non-NULL. paBlob may be NULL or non-NULL. */
- assert( pnBlob );
-
- if( p->pSegments ){
- rc = sqlite3_blob_reopen(p->pSegments, iBlockid);
- }else{
- if( 0==p->zSegmentsTbl ){
- p->zSegmentsTbl = sqlite3_mprintf("%s_segments", p->zName);
- if( 0==p->zSegmentsTbl ) return SQLITE_NOMEM;
- }
- rc = sqlite3_blob_open(
- p->db, p->zDb, p->zSegmentsTbl, "block", iBlockid, 0, &p->pSegments
- );
- }
-
- if( rc==SQLITE_OK ){
- int nByte = sqlite3_blob_bytes(p->pSegments);
- *pnBlob = nByte;
- if( paBlob ){
- char *aByte = sqlite3_malloc(nByte + FTS3_NODE_PADDING);
- if( !aByte ){
- rc = SQLITE_NOMEM;
- }else{
- if( pnLoad && nByte>(FTS3_NODE_CHUNK_THRESHOLD) ){
- nByte = FTS3_NODE_CHUNKSIZE;
- *pnLoad = nByte;
- }
- rc = sqlite3_blob_read(p->pSegments, aByte, nByte, 0);
- memset(&aByte[nByte], 0, FTS3_NODE_PADDING);
- if( rc!=SQLITE_OK ){
- sqlite3_free(aByte);
- aByte = 0;
- }
- }
- *paBlob = aByte;
- }
- }
-
- return rc;
-}
-
-/*
-** Close the blob handle at p->pSegments, if it is open. See comments above
-** the sqlite3Fts3ReadBlock() function for details.
-*/
-void sqlite3Fts3SegmentsClose(Fts3Table *p){
- sqlite3_blob_close(p->pSegments);
- p->pSegments = 0;
-}
-
-static int fts3SegReaderIncrRead(Fts3SegReader *pReader){
- int nRead; /* Number of bytes to read */
- int rc; /* Return code */
-
- nRead = MIN(pReader->nNode - pReader->nPopulate, FTS3_NODE_CHUNKSIZE);
- rc = sqlite3_blob_read(
- pReader->pBlob,
- &pReader->aNode[pReader->nPopulate],
- nRead,
- pReader->nPopulate
- );
-
- if( rc==SQLITE_OK ){
- pReader->nPopulate += nRead;
- memset(&pReader->aNode[pReader->nPopulate], 0, FTS3_NODE_PADDING);
- if( pReader->nPopulate==pReader->nNode ){
- sqlite3_blob_close(pReader->pBlob);
- pReader->pBlob = 0;
- pReader->nPopulate = 0;
- }
- }
- return rc;
-}
-
-static int fts3SegReaderRequire(Fts3SegReader *pReader, char *pFrom, int nByte){
- int rc = SQLITE_OK;
- assert( !pReader->pBlob
- || (pFrom>=pReader->aNode && pFrom<&pReader->aNode[pReader->nNode])
- );
- while( pReader->pBlob && rc==SQLITE_OK
- && (pFrom - pReader->aNode + nByte)>pReader->nPopulate
- ){
- rc = fts3SegReaderIncrRead(pReader);
- }
- return rc;
-}
-
-/*
-** Set an Fts3SegReader cursor to point at EOF.
-*/
-static void fts3SegReaderSetEof(Fts3SegReader *pSeg){
- if( !fts3SegReaderIsRootOnly(pSeg) ){
- sqlite3_free(pSeg->aNode);
- sqlite3_blob_close(pSeg->pBlob);
- pSeg->pBlob = 0;
- }
- pSeg->aNode = 0;
-}
-
-/*
-** Move the iterator passed as the first argument to the next term in the
-** segment. If successful, SQLITE_OK is returned. If there is no next term,
-** SQLITE_DONE. Otherwise, an SQLite error code.
-*/
-static int fts3SegReaderNext(
- Fts3Table *p,
- Fts3SegReader *pReader,
- int bIncr
-){
- int rc; /* Return code of various sub-routines */
- char *pNext; /* Cursor variable */
- int nPrefix; /* Number of bytes in term prefix */
- int nSuffix; /* Number of bytes in term suffix */
-
- if( !pReader->aDoclist ){
- pNext = pReader->aNode;
- }else{
- pNext = &pReader->aDoclist[pReader->nDoclist];
- }
-
- if( !pNext || pNext>=&pReader->aNode[pReader->nNode] ){
-
- if( fts3SegReaderIsPending(pReader) ){
- Fts3HashElem *pElem = *(pReader->ppNextElem);
- if( pElem==0 ){
- pReader->aNode = 0;
- }else{
- PendingList *pList = (PendingList *)fts3HashData(pElem);
- pReader->zTerm = (char *)fts3HashKey(pElem);
- pReader->nTerm = fts3HashKeysize(pElem);
- pReader->nNode = pReader->nDoclist = pList->nData + 1;
- pReader->aNode = pReader->aDoclist = pList->aData;
- pReader->ppNextElem++;
- assert( pReader->aNode );
- }
- return SQLITE_OK;
- }
-
- fts3SegReaderSetEof(pReader);
-
- /* If iCurrentBlock>=iLeafEndBlock, this is an EOF condition. All leaf
- ** blocks have already been traversed. */
- assert( pReader->iCurrentBlock<=pReader->iLeafEndBlock );
- if( pReader->iCurrentBlock>=pReader->iLeafEndBlock ){
- return SQLITE_OK;
- }
-
- rc = sqlite3Fts3ReadBlock(
- p, ++pReader->iCurrentBlock, &pReader->aNode, &pReader->nNode,
- (bIncr ? &pReader->nPopulate : 0)
- );
- if( rc!=SQLITE_OK ) return rc;
- assert( pReader->pBlob==0 );
- if( bIncr && pReader->nPopulate<pReader->nNode ){
- pReader->pBlob = p->pSegments;
- p->pSegments = 0;
- }
- pNext = pReader->aNode;
- }
-
- assert( !fts3SegReaderIsPending(pReader) );
-
- rc = fts3SegReaderRequire(pReader, pNext, FTS3_VARINT_MAX*2);
- if( rc!=SQLITE_OK ) return rc;
-
- /* 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 += fts3GetVarint32(pNext, &nPrefix);
- pNext += fts3GetVarint32(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;
- }
- pReader->zTerm = zNew;
- pReader->nTermAlloc = nNew;
- }
-
- rc = fts3SegReaderRequire(pReader, pNext, nSuffix+FTS3_VARINT_MAX);
- if( rc!=SQLITE_OK ) return rc;
-
- memcpy(&pReader->zTerm[nPrefix], pNext, nSuffix);
- pReader->nTerm = nPrefix+nSuffix;
- pNext += nSuffix;
- pNext += fts3GetVarint32(pNext, &pReader->nDoclist);
- pReader->aDoclist = pNext;
- pReader->pOffsetList = 0;
-
- /* 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.
-*/
-static int fts3SegReaderFirstDocid(Fts3Table *pTab, Fts3SegReader *pReader){
- int rc = SQLITE_OK;
- assert( pReader->aDoclist );
- assert( !pReader->pOffsetList );
- if( pTab->bDescIdx && fts3SegReaderIsPending(pReader) ){
- u8 bEof = 0;
- pReader->iDocid = 0;
- pReader->nOffsetList = 0;
- sqlite3Fts3DoclistPrev(0,
- pReader->aDoclist, pReader->nDoclist, &pReader->pOffsetList,
- &pReader->iDocid, &pReader->nOffsetList, &bEof
- );
- }else{
- rc = fts3SegReaderRequire(pReader, pReader->aDoclist, FTS3_VARINT_MAX);
- if( rc==SQLITE_OK ){
- int n = sqlite3Fts3GetVarint(pReader->aDoclist, &pReader->iDocid);
- pReader->pOffsetList = &pReader->aDoclist[n];
- }
- }
- return rc;
-}
-
-/*
-** Advance the SegReader to point to the next docid in the doclist
-** associated with the current term.
-**
-** If arguments ppOffsetList and pnOffsetList are not NULL, then
-** *ppOffsetList is set to point to the first column-offset list
-** in the doclist entry (i.e. immediately past the docid varint).
-** *pnOffsetList is set to the length of the set of column-offset
-** lists, not including the nul-terminator byte. For example:
-*/
-static int fts3SegReaderNextDocid(
- Fts3Table *pTab,
- Fts3SegReader *pReader, /* Reader to advance to next docid */
- char **ppOffsetList, /* OUT: Pointer to current position-list */
- int *pnOffsetList /* OUT: Length of *ppOffsetList in bytes */
-){
- int rc = SQLITE_OK;
- char *p = pReader->pOffsetList;
- char c = 0;
-
- assert( p );
-
- if( pTab->bDescIdx && fts3SegReaderIsPending(pReader) ){
- /* A pending-terms seg-reader for an FTS4 table that uses order=desc.
- ** Pending-terms doclists are always built up in ascending order, so
- ** we have to iterate through them backwards here. */
- u8 bEof = 0;
- if( ppOffsetList ){
- *ppOffsetList = pReader->pOffsetList;
- *pnOffsetList = pReader->nOffsetList - 1;
- }
- sqlite3Fts3DoclistPrev(0,
- pReader->aDoclist, pReader->nDoclist, &p, &pReader->iDocid,
- &pReader->nOffsetList, &bEof
- );
- if( bEof ){
- pReader->pOffsetList = 0;
- }else{
- pReader->pOffsetList = p;
- }
- }else{
- char *pEnd = &pReader->aDoclist[pReader->nDoclist];
-
- /* Pointer p currently points at the first byte of an offset list. The
- ** following block advances it to point one byte past the end of
- ** the same offset list. */
- while( 1 ){
-
- /* The following line of code (and the "p++" below the while() loop) is
- ** normally all that is required to move pointer p to the desired
- ** position. The exception is if this node is being loaded from disk
- ** incrementally and pointer "p" now points to the first byte past
- ** the populated part of pReader->aNode[].
- */
- while( *p | c ) c = *p++ & 0x80;
- assert( *p==0 );
-
- if( pReader->pBlob==0 || p<&pReader->aNode[pReader->nPopulate] ) break;
- rc = fts3SegReaderIncrRead(pReader);
- if( rc!=SQLITE_OK ) return rc;
- }
- p++;
-
- /* If required, populate the output variables with a pointer to and the
- ** size of the previous offset-list.
- */
- if( ppOffsetList ){
- *ppOffsetList = pReader->pOffsetList;
- *pnOffsetList = (int)(p - pReader->pOffsetList - 1);
- }
-
- /* List may have been edited in place by fts3EvalNearTrim() */
- while( p<pEnd && *p==0 ) p++;
-
- /* If there are no more entries in the doclist, set pOffsetList to
- ** NULL. Otherwise, set Fts3SegReader.iDocid to the next docid and
- ** Fts3SegReader.pOffsetList to point to the next offset list before
- ** returning.
- */
- if( p>=pEnd ){
- pReader->pOffsetList = 0;
- }else{
- rc = fts3SegReaderRequire(pReader, p, FTS3_VARINT_MAX);
- if( rc==SQLITE_OK ){
- sqlite3_int64 iDelta;
- pReader->pOffsetList = p + sqlite3Fts3GetVarint(p, &iDelta);
- if( pTab->bDescIdx ){
- pReader->iDocid -= iDelta;
- }else{
- pReader->iDocid += iDelta;
- }
- }
- }
- }
-
- return SQLITE_OK;
-}
-
-
-int sqlite3Fts3MsrOvfl(
- Fts3Cursor *pCsr,
- Fts3MultiSegReader *pMsr,
- int *pnOvfl
-){
- Fts3Table *p = (Fts3Table*)pCsr->base.pVtab;
- int nOvfl = 0;
- int ii;
- int rc = SQLITE_OK;
- int pgsz = p->nPgsz;
-
- assert( p->bFts4 );
- assert( pgsz>0 );
-
- for(ii=0; rc==SQLITE_OK && ii<pMsr->nSegment; ii++){
- Fts3SegReader *pReader = pMsr->apSegment[ii];
- if( !fts3SegReaderIsPending(pReader)
- && !fts3SegReaderIsRootOnly(pReader)
- ){
- sqlite3_int64 jj;
- for(jj=pReader->iStartBlock; jj<=pReader->iLeafEndBlock; jj++){
- int nBlob;
- rc = sqlite3Fts3ReadBlock(p, jj, 0, &nBlob, 0);
- if( rc!=SQLITE_OK ) break;
- if( (nBlob+35)>pgsz ){
- nOvfl += (nBlob + 34)/pgsz;
- }
- }
- }
- }
- *pnOvfl = nOvfl;
- return rc;
-}
-
-/*
-** Free all allocations associated with the iterator passed as the
-** second argument.
-*/
-void sqlite3Fts3SegReaderFree(Fts3SegReader *pReader){
- if( pReader && !fts3SegReaderIsPending(pReader) ){
- sqlite3_free(pReader->zTerm);
- if( !fts3SegReaderIsRootOnly(pReader) ){
- sqlite3_free(pReader->aNode);
- sqlite3_blob_close(pReader->pBlob);
- }
- }
- sqlite3_free(pReader);
-}
-
-/*
-** Allocate a new SegReader object.
-*/
-int sqlite3Fts3SegReaderNew(
- int iAge, /* Segment "age". */
- int bLookup, /* True for a lookup only */
- sqlite3_int64 iStartLeaf, /* First leaf to traverse */
- sqlite3_int64 iEndLeaf, /* Final leaf to traverse */
- sqlite3_int64 iEndBlock, /* Final block of segment */
- const char *zRoot, /* Buffer containing root node */
- int nRoot, /* Size of buffer containing root node */
- Fts3SegReader **ppReader /* OUT: Allocated Fts3SegReader */
-){
- Fts3SegReader *pReader; /* Newly allocated SegReader object */
- int nExtra = 0; /* Bytes to allocate segment root node */
-
- assert( iStartLeaf<=iEndLeaf );
- if( iStartLeaf==0 ){
- nExtra = nRoot + FTS3_NODE_PADDING;
- }
-
- pReader = (Fts3SegReader *)sqlite3_malloc(sizeof(Fts3SegReader) + nExtra);
- if( !pReader ){
- return SQLITE_NOMEM;
- }
- memset(pReader, 0, sizeof(Fts3SegReader));
- pReader->iIdx = iAge;
- pReader->bLookup = bLookup!=0;
- pReader->iStartBlock = iStartLeaf;
- pReader->iLeafEndBlock = iEndLeaf;
- pReader->iEndBlock = iEndBlock;
-
- if( nExtra ){
- /* The entire segment is stored in the root node. */
- pReader->aNode = (char *)&pReader[1];
- pReader->rootOnly = 1;
- pReader->nNode = nRoot;
- memcpy(pReader->aNode, zRoot, nRoot);
- memset(&pReader->aNode[nRoot], 0, FTS3_NODE_PADDING);
- }else{
- pReader->iCurrentBlock = iStartLeaf-1;
- }
- *ppReader = pReader;
- return SQLITE_OK;
-}
-
-/*
-** This is a comparison function used as a qsort() callback when sorting
-** an array of pending terms by term. This occurs as part of flushing
-** the contents of the pending-terms hash table to the database.
-*/
-static int fts3CompareElemByTerm(const void *lhs, const void *rhs){
- char *z1 = fts3HashKey(*(Fts3HashElem **)lhs);
- char *z2 = fts3HashKey(*(Fts3HashElem **)rhs);
- int n1 = fts3HashKeysize(*(Fts3HashElem **)lhs);
- int n2 = fts3HashKeysize(*(Fts3HashElem **)rhs);
-
- int n = (n1<n2 ? n1 : n2);
- int c = memcmp(z1, z2, n);
- if( c==0 ){
- c = n1 - n2;
- }
- return c;
-}
-
-/*
-** This function is used to allocate an Fts3SegReader that iterates through
-** a subset of the terms stored in the Fts3Table.pendingTerms array.
-**
-** If the isPrefixIter parameter is zero, then the returned SegReader iterates
-** through each term in the pending-terms table. Or, if isPrefixIter is
-** non-zero, it iterates through each term and its prefixes. For example, if
-** the pending terms hash table contains the terms "sqlite", "mysql" and
-** "firebird", then the iterator visits the following 'terms' (in the order
-** shown):
-**
-** f fi fir fire fireb firebi firebir firebird
-** m my mys mysq mysql
-** s sq sql sqli sqlit sqlite
-**
-** Whereas if isPrefixIter is zero, the terms visited are:
-**
-** firebird mysql sqlite
-*/
-int sqlite3Fts3SegReaderPending(
- Fts3Table *p, /* Virtual table handle */
- int iIndex, /* Index for p->aIndex */
- const char *zTerm, /* Term to search for */
- int nTerm, /* Size of buffer zTerm */
- int bPrefix, /* True for a prefix iterator */
- Fts3SegReader **ppReader /* OUT: SegReader for pending-terms */
-){
- Fts3SegReader *pReader = 0; /* Fts3SegReader object to return */
- Fts3HashElem *pE; /* Iterator variable */
- Fts3HashElem **aElem = 0; /* Array of term hash entries to scan */
- int nElem = 0; /* Size of array at aElem */
- int rc = SQLITE_OK; /* Return Code */
- Fts3Hash *pHash;
-
- pHash = &p->aIndex[iIndex].hPending;
- if( bPrefix ){
- int nAlloc = 0; /* Size of allocated array at aElem */
-
- for(pE=fts3HashFirst(pHash); pE; pE=fts3HashNext(pE)){
- char *zKey = (char *)fts3HashKey(pE);
- int nKey = fts3HashKeysize(pE);
- if( nTerm==0 || (nKey>=nTerm && 0==memcmp(zKey, zTerm, nTerm)) ){
- if( nElem==nAlloc ){
- Fts3HashElem **aElem2;
- nAlloc += 16;
- aElem2 = (Fts3HashElem **)sqlite3_realloc(
- aElem, nAlloc*sizeof(Fts3HashElem *)
- );
- if( !aElem2 ){
- rc = SQLITE_NOMEM;
- nElem = 0;
- break;
- }
- aElem = aElem2;
- }
-
- aElem[nElem++] = pE;
- }
- }
-
- /* If more than one term matches the prefix, sort the Fts3HashElem
- ** objects in term order using qsort(). This uses the same comparison
- ** callback as is used when flushing terms to disk.
- */
- if( nElem>1 ){
- qsort(aElem, nElem, sizeof(Fts3HashElem *), fts3CompareElemByTerm);
- }
-
- }else{
- /* The query is a simple term lookup that matches at most one term in
- ** the index. All that is required is a straight hash-lookup.
- **
- ** Because the stack address of pE may be accessed via the aElem pointer
- ** below, the "Fts3HashElem *pE" must be declared so that it is valid
- ** within this entire function, not just this "else{...}" block.
- */
- pE = fts3HashFindElem(pHash, zTerm, nTerm);
- if( pE ){
- aElem = &pE;
- nElem = 1;
- }
- }
-
- if( nElem>0 ){
- int nByte = sizeof(Fts3SegReader) + (nElem+1)*sizeof(Fts3HashElem *);
- pReader = (Fts3SegReader *)sqlite3_malloc(nByte);
- if( !pReader ){
- rc = SQLITE_NOMEM;
- }else{
- memset(pReader, 0, nByte);
- pReader->iIdx = 0x7FFFFFFF;
- pReader->ppNextElem = (Fts3HashElem **)&pReader[1];
- memcpy(pReader->ppNextElem, aElem, nElem*sizeof(Fts3HashElem *));
- }
- }
-
- if( bPrefix ){
- sqlite3_free(aElem);
- }
- *ppReader = pReader;
- return rc;
-}
-
-/*
-** Compare the entries pointed to by two Fts3SegReader structures.
-** Comparison is as follows:
-**
-** 1) EOF is greater than not EOF.
-**
-** 2) The current terms (if any) are compared using memcmp(). If one
-** term is a prefix of another, the longer term is considered the
-** larger.
-**
-** 3) By segment age. An older segment is considered larger.
-*/
-static int fts3SegReaderCmp(Fts3SegReader *pLhs, Fts3SegReader *pRhs){
- int rc;
- if( pLhs->aNode && pRhs->aNode ){
- int rc2 = pLhs->nTerm - pRhs->nTerm;
- if( rc2<0 ){
- rc = memcmp(pLhs->zTerm, pRhs->zTerm, pLhs->nTerm);
- }else{
- rc = memcmp(pLhs->zTerm, pRhs->zTerm, pRhs->nTerm);
- }
- if( rc==0 ){
- rc = rc2;
- }
- }else{
- rc = (pLhs->aNode==0) - (pRhs->aNode==0);
- }
- if( rc==0 ){
- rc = pRhs->iIdx - pLhs->iIdx;
- }
- assert( rc!=0 );
- return rc;
-}
-
-/*
-** A different comparison function for SegReader structures. In this
-** version, it is assumed that each SegReader points to an entry in
-** a doclist for identical terms. Comparison is made as follows:
-**
-** 1) EOF (end of doclist in this case) is greater than not EOF.
-**
-** 2) By current docid.
-**
-** 3) By segment age. An older segment is considered larger.
-*/
-static int fts3SegReaderDoclistCmp(Fts3SegReader *pLhs, Fts3SegReader *pRhs){
- int rc = (pLhs->pOffsetList==0)-(pRhs->pOffsetList==0);
- if( rc==0 ){
- if( pLhs->iDocid==pRhs->iDocid ){
- rc = pRhs->iIdx - pLhs->iIdx;
- }else{
- rc = (pLhs->iDocid > pRhs->iDocid) ? 1 : -1;
- }
- }
- assert( pLhs->aNode && pRhs->aNode );
- return rc;
-}
-static int fts3SegReaderDoclistCmpRev(Fts3SegReader *pLhs, Fts3SegReader *pRhs){
- int rc = (pLhs->pOffsetList==0)-(pRhs->pOffsetList==0);
- if( rc==0 ){
- if( pLhs->iDocid==pRhs->iDocid ){
- rc = pRhs->iIdx - pLhs->iIdx;
- }else{
- rc = (pLhs->iDocid < pRhs->iDocid) ? 1 : -1;
- }
- }
- assert( pLhs->aNode && pRhs->aNode );
- return rc;
-}
-
-/*
-** Compare the term that the Fts3SegReader object passed as the first argument
-** points to with the term specified by arguments zTerm and nTerm.
-**
-** If the pSeg iterator is already at EOF, return 0. Otherwise, return
-** -ve if the pSeg term is less than zTerm/nTerm, 0 if the two terms are
-** equal, or +ve if the pSeg term is greater than zTerm/nTerm.
-*/
-static int fts3SegReaderTermCmp(
- Fts3SegReader *pSeg, /* Segment reader object */
- const char *zTerm, /* Term to compare to */
- int nTerm /* Size of term zTerm in bytes */
-){
- int res = 0;
- if( pSeg->aNode ){
- if( pSeg->nTerm>nTerm ){
- res = memcmp(pSeg->zTerm, zTerm, nTerm);
- }else{
- res = memcmp(pSeg->zTerm, zTerm, pSeg->nTerm);
- }
- if( res==0 ){
- res = pSeg->nTerm-nTerm;
- }
- }
- return res;
-}
-
-/*
-** Argument apSegment is an array of nSegment elements. It is known that
-** the final (nSegment-nSuspect) members are already in sorted order
-** (according to the comparison function provided). This function shuffles
-** the array around until all entries are in sorted order.
-*/
-static void fts3SegReaderSort(
- Fts3SegReader **apSegment, /* Array to sort entries of */
- int nSegment, /* Size of apSegment array */
- int nSuspect, /* Unsorted entry count */
- int (*xCmp)(Fts3SegReader *, Fts3SegReader *) /* Comparison function */
-){
- int i; /* Iterator variable */
-
- assert( nSuspect<=nSegment );
-
- if( nSuspect==nSegment ) nSuspect--;
- for(i=nSuspect-1; i>=0; i--){
- int j;
- for(j=i; j<(nSegment-1); j++){
- Fts3SegReader *pTmp;
- if( xCmp(apSegment[j], apSegment[j+1])<0 ) break;
- pTmp = apSegment[j+1];
- apSegment[j+1] = apSegment[j];
- apSegment[j] = pTmp;
- }
- }
-
-#ifndef NDEBUG
- /* Check that the list really is sorted now. */
- for(i=0; i<(nSuspect-1); i++){
- assert( xCmp(apSegment[i], apSegment[i+1])<0 );
- }
-#endif
-}
-
-/*
-** Insert a record into the %_segments table.
-*/
-static int fts3WriteSegment(
- Fts3Table *p, /* Virtual table handle */
- sqlite3_int64 iBlock, /* Block id for new block */
- char *z, /* Pointer to buffer containing block data */
- int n /* Size of buffer z in bytes */
-){
- sqlite3_stmt *pStmt;
- int rc = fts3SqlStmt(p, SQL_INSERT_SEGMENTS, &pStmt, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pStmt, 1, iBlock);
- sqlite3_bind_blob(pStmt, 2, z, n, SQLITE_STATIC);
- sqlite3_step(pStmt);
- rc = sqlite3_reset(pStmt);
- }
- return rc;
-}
-
-/*
-** Find the largest relative level number in the table. If successful, set
-** *pnMax to this value and return SQLITE_OK. Otherwise, if an error occurs,
-** set *pnMax to zero and return an SQLite error code.
-*/
-int sqlite3Fts3MaxLevel(Fts3Table *p, int *pnMax){
- int rc;
- int mxLevel = 0;
- sqlite3_stmt *pStmt = 0;
-
- rc = fts3SqlStmt(p, SQL_SELECT_MXLEVEL, &pStmt, 0);
- if( rc==SQLITE_OK ){
- if( SQLITE_ROW==sqlite3_step(pStmt) ){
- mxLevel = sqlite3_column_int(pStmt, 0);
- }
- rc = sqlite3_reset(pStmt);
- }
- *pnMax = mxLevel;
- 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 */
- sqlite3_int64 nLeafData, /* Bytes of leaf data in segment */
- 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);
- if( nLeafData==0 ){
- sqlite3_bind_int64(pStmt, 5, iEndBlock);
- }else{
- char *zEnd = sqlite3_mprintf("%lld %lld", iEndBlock, nLeafData);
- if( !zEnd ) return SQLITE_NOMEM;
- sqlite3_bind_text(pStmt, 5, zEnd, -1, sqlite3_free);
- }
- sqlite3_bind_blob(pStmt, 6, zRoot, nRoot, SQLITE_STATIC);
- sqlite3_step(pStmt);
- rc = sqlite3_reset(pStmt);
- }
- return rc;
-}
-
-/*
-** Return the size of the common prefix (if any) shared by zPrev and
-** zNext, in bytes. For example,
-**
-** fts3PrefixCompress("abc", 3, "abcdef", 6) // returns 3
-** fts3PrefixCompress("abX", 3, "abcdef", 6) // returns 2
-** fts3PrefixCompress("abX", 3, "Xbcdef", 6) // returns 0
-*/
-static int fts3PrefixCompress(
- const char *zPrev, /* Buffer containing previous term */
- int nPrev, /* Size of buffer zPrev in bytes */
- const char *zNext, /* Buffer containing next term */
- int nNext /* Size of buffer zNext in bytes */
-){
- int n;
- UNUSED_PARAMETER(nNext);
- for(n=0; n<nPrev && zPrev[n]==zNext[n]; n++);
- return n;
-}
-
-/*
-** Add term zTerm to the SegmentNode. It is guaranteed that zTerm is larger
-** (according to memcmp) than the previous term.
-*/
-static int fts3NodeAddTerm(
- Fts3Table *p, /* Virtual table handle */
- SegmentNode **ppTree, /* IN/OUT: SegmentNode handle */
- int isCopyTerm, /* True if zTerm/nTerm is transient */
- const char *zTerm, /* Pointer to buffer containing term */
- int nTerm /* Size of term in bytes */
-){
- SegmentNode *pTree = *ppTree;
- int rc;
- SegmentNode *pNew;
-
- /* First try to append the term to the current node. Return early if
- ** this is possible.
- */
- if( pTree ){
- int nData = pTree->nData; /* Current size of node in bytes */
- int nReq = nData; /* Required space after adding zTerm */
- int nPrefix; /* Number of bytes of prefix compression */
- int nSuffix; /* Suffix length */
-
- nPrefix = fts3PrefixCompress(pTree->zTerm, pTree->nTerm, zTerm, nTerm);
- nSuffix = nTerm-nPrefix;
-
- nReq += sqlite3Fts3VarintLen(nPrefix)+sqlite3Fts3VarintLen(nSuffix)+nSuffix;
- if( nReq<=p->nNodeSize || !pTree->zTerm ){
-
- if( nReq>p->nNodeSize ){
- /* An unusual case: this is the first term to be added to the node
- ** and the static node buffer (p->nNodeSize bytes) is not large
- ** enough. Use a separately malloced buffer instead This wastes
- ** p->nNodeSize bytes, but since this scenario only comes about when
- ** the database contain two terms that share a prefix of almost 2KB,
- ** this is not expected to be a serious problem.
- */
- assert( pTree->aData==(char *)&pTree[1] );
- pTree->aData = (char *)sqlite3_malloc(nReq);
- if( !pTree->aData ){
- return SQLITE_NOMEM;
- }
- }
-
- if( pTree->zTerm ){
- /* There is no prefix-length field for first term in a node */
- nData += sqlite3Fts3PutVarint(&pTree->aData[nData], nPrefix);
- }
-
- nData += sqlite3Fts3PutVarint(&pTree->aData[nData], nSuffix);
- memcpy(&pTree->aData[nData], &zTerm[nPrefix], nSuffix);
- pTree->nData = nData + nSuffix;
- pTree->nEntry++;
-
- if( isCopyTerm ){
- if( pTree->nMalloc<nTerm ){
- char *zNew = sqlite3_realloc(pTree->zMalloc, nTerm*2);
- if( !zNew ){
- return SQLITE_NOMEM;
- }
- pTree->nMalloc = nTerm*2;
- pTree->zMalloc = zNew;
- }
- pTree->zTerm = pTree->zMalloc;
- memcpy(pTree->zTerm, zTerm, nTerm);
- pTree->nTerm = nTerm;
- }else{
- pTree->zTerm = (char *)zTerm;
- pTree->nTerm = nTerm;
- }
- return SQLITE_OK;
- }
- }
-
- /* If control flows to here, it was not possible to append zTerm to the
- ** current node. Create a new node (a right-sibling of the current node).
- ** If this is the first node in the tree, the term is added to it.
- **
- ** Otherwise, the term is not added to the new node, it is left empty for
- ** now. Instead, the term is inserted into the parent of pTree. If pTree
- ** has no parent, one is created here.
- */
- pNew = (SegmentNode *)sqlite3_malloc(sizeof(SegmentNode) + p->nNodeSize);
- if( !pNew ){
- return SQLITE_NOMEM;
- }
- memset(pNew, 0, sizeof(SegmentNode));
- pNew->nData = 1 + FTS3_VARINT_MAX;
- pNew->aData = (char *)&pNew[1];
-
- if( pTree ){
- SegmentNode *pParent = pTree->pParent;
- rc = fts3NodeAddTerm(p, &pParent, isCopyTerm, zTerm, nTerm);
- if( pTree->pParent==0 ){
- pTree->pParent = pParent;
- }
- pTree->pRight = pNew;
- pNew->pLeftmost = pTree->pLeftmost;
- pNew->pParent = pParent;
- pNew->zMalloc = pTree->zMalloc;
- pNew->nMalloc = pTree->nMalloc;
- pTree->zMalloc = 0;
- }else{
- pNew->pLeftmost = pNew;
- rc = fts3NodeAddTerm(p, &pNew, isCopyTerm, zTerm, nTerm);
- }
-
- *ppTree = pNew;
- return rc;
-}
-
-/*
-** Helper function for fts3NodeWrite().
-*/
-static int fts3TreeFinishNode(
- SegmentNode *pTree,
- int iHeight,
- sqlite3_int64 iLeftChild
-){
- int nStart;
- assert( iHeight>=1 && iHeight<128 );
- nStart = FTS3_VARINT_MAX - sqlite3Fts3VarintLen(iLeftChild);
- pTree->aData[nStart] = (char)iHeight;
- sqlite3Fts3PutVarint(&pTree->aData[nStart+1], iLeftChild);
- return nStart;
-}
-
-/*
-** Write the buffer for the segment node pTree and all of its peers to the
-** database. Then call this function recursively to write the parent of
-** pTree and its peers to the database.
-**
-** Except, if pTree is a root node, do not write it to the database. Instead,
-** set output variables *paRoot and *pnRoot to contain the root node.
-**
-** If successful, SQLITE_OK is returned and output variable *piLast is
-** set to the largest blockid written to the database (or zero if no
-** blocks were written to the db). Otherwise, an SQLite error code is
-** returned.
-*/
-static int fts3NodeWrite(
- Fts3Table *p, /* Virtual table handle */
- SegmentNode *pTree, /* SegmentNode handle */
- int iHeight, /* Height of this node in tree */
- sqlite3_int64 iLeaf, /* Block id of first leaf node */
- sqlite3_int64 iFree, /* Block id of next free slot in %_segments */
- sqlite3_int64 *piLast, /* OUT: Block id of last entry written */
- char **paRoot, /* OUT: Data for root node */
- int *pnRoot /* OUT: Size of root node in bytes */
-){
- int rc = SQLITE_OK;
-
- if( !pTree->pParent ){
- /* Root node of the tree. */
- int nStart = fts3TreeFinishNode(pTree, iHeight, iLeaf);
- *piLast = iFree-1;
- *pnRoot = pTree->nData - nStart;
- *paRoot = &pTree->aData[nStart];
- }else{
- SegmentNode *pIter;
- sqlite3_int64 iNextFree = iFree;
- sqlite3_int64 iNextLeaf = iLeaf;
- for(pIter=pTree->pLeftmost; pIter && rc==SQLITE_OK; pIter=pIter->pRight){
- int nStart = fts3TreeFinishNode(pIter, iHeight, iNextLeaf);
- int nWrite = pIter->nData - nStart;
-
- rc = fts3WriteSegment(p, iNextFree, &pIter->aData[nStart], nWrite);
- iNextFree++;
- iNextLeaf += (pIter->nEntry+1);
- }
- if( rc==SQLITE_OK ){
- assert( iNextLeaf==iFree );
- rc = fts3NodeWrite(
- p, pTree->pParent, iHeight+1, iFree, iNextFree, piLast, paRoot, pnRoot
- );
- }
- }
-
- return rc;
-}
-
-/*
-** Free all memory allocations associated with the tree pTree.
-*/
-static void fts3NodeFree(SegmentNode *pTree){
- if( pTree ){
- SegmentNode *p = pTree->pLeftmost;
- fts3NodeFree(p->pParent);
- while( p ){
- SegmentNode *pRight = p->pRight;
- if( p->aData!=(char *)&p[1] ){
- sqlite3_free(p->aData);
- }
- assert( pRight==0 || p->zMalloc==0 );
- sqlite3_free(p->zMalloc);
- sqlite3_free(p);
- p = pRight;
- }
- }
-}
-
-/*
-** Add a term to the segment being constructed by the SegmentWriter object
-** *ppWriter. When adding the first term to a segment, *ppWriter should
-** be passed NULL. This function will allocate a new SegmentWriter object
-** and return it via the input/output variable *ppWriter in this case.
-**
-** If successful, SQLITE_OK is returned. Otherwise, an SQLite error code.
-*/
-static int fts3SegWriterAdd(
- Fts3Table *p, /* Virtual table handle */
- SegmentWriter **ppWriter, /* IN/OUT: SegmentWriter handle */
- int isCopyTerm, /* True if buffer zTerm must be copied */
- const char *zTerm, /* Pointer to buffer containing term */
- int nTerm, /* Size of term in bytes */
- const char *aDoclist, /* Pointer to buffer containing doclist */
- int nDoclist /* Size of doclist in bytes */
-){
- int nPrefix; /* Size of term prefix in bytes */
- int nSuffix; /* Size of term suffix in bytes */
- int nReq; /* Number of bytes required on leaf page */
- int nData;
- SegmentWriter *pWriter = *ppWriter;
-
- if( !pWriter ){
- int rc;
- sqlite3_stmt *pStmt;
-
- /* Allocate the SegmentWriter structure */
- pWriter = (SegmentWriter *)sqlite3_malloc(sizeof(SegmentWriter));
- if( !pWriter ) return SQLITE_NOMEM;
- memset(pWriter, 0, sizeof(SegmentWriter));
- *ppWriter = pWriter;
-
- /* Allocate a buffer in which to accumulate data */
- pWriter->aData = (char *)sqlite3_malloc(p->nNodeSize);
- if( !pWriter->aData ) return SQLITE_NOMEM;
- pWriter->nSize = p->nNodeSize;
-
- /* Find the next free blockid in the %_segments table */
- rc = fts3SqlStmt(p, SQL_NEXT_SEGMENTS_ID, &pStmt, 0);
- if( rc!=SQLITE_OK ) return rc;
- if( SQLITE_ROW==sqlite3_step(pStmt) ){
- pWriter->iFree = sqlite3_column_int64(pStmt, 0);
- pWriter->iFirst = pWriter->iFree;
- }
- rc = sqlite3_reset(pStmt);
- if( rc!=SQLITE_OK ) return rc;
- }
- nData = pWriter->nData;
-
- nPrefix = fts3PrefixCompress(pWriter->zTerm, pWriter->nTerm, zTerm, nTerm);
- nSuffix = nTerm-nPrefix;
-
- /* Figure out how many bytes are required by this new entry */
- nReq = sqlite3Fts3VarintLen(nPrefix) + /* varint containing prefix size */
- sqlite3Fts3VarintLen(nSuffix) + /* varint containing suffix size */
- nSuffix + /* Term suffix */
- sqlite3Fts3VarintLen(nDoclist) + /* Size of doclist */
- nDoclist; /* Doclist data */
-
- if( nData>0 && nData+nReq>p->nNodeSize ){
- int rc;
-
- /* The current leaf node is full. Write it out to the database. */
- rc = fts3WriteSegment(p, pWriter->iFree++, pWriter->aData, nData);
- if( rc!=SQLITE_OK ) return rc;
- p->nLeafAdd++;
-
- /* Add the current term to the interior node tree. The term added to
- ** the interior tree must:
- **
- ** a) be greater than the largest term on the leaf node just written
- ** to the database (still available in pWriter->zTerm), and
- **
- ** b) be less than or equal to the term about to be added to the new
- ** leaf node (zTerm/nTerm).
- **
- ** In other words, it must be the prefix of zTerm 1 byte longer than
- ** the common prefix (if any) of zTerm and pWriter->zTerm.
- */
- assert( nPrefix<nTerm );
- rc = fts3NodeAddTerm(p, &pWriter->pTree, isCopyTerm, zTerm, nPrefix+1);
- if( rc!=SQLITE_OK ) return rc;
-
- nData = 0;
- pWriter->nTerm = 0;
-
- nPrefix = 0;
- nSuffix = nTerm;
- nReq = 1 + /* varint containing prefix size */
- sqlite3Fts3VarintLen(nTerm) + /* varint containing suffix size */
- nTerm + /* Term suffix */
- sqlite3Fts3VarintLen(nDoclist) + /* Size of doclist */
- nDoclist; /* Doclist data */
- }
-
- /* Increase the total number of bytes written to account for the new entry. */
- pWriter->nLeafData += nReq;
-
- /* If the buffer currently allocated is too small for this entry, realloc
- ** the buffer to make it large enough.
- */
- if( nReq>pWriter->nSize ){
- char *aNew = sqlite3_realloc(pWriter->aData, nReq);
- if( !aNew ) return SQLITE_NOMEM;
- pWriter->aData = aNew;
- pWriter->nSize = nReq;
- }
- assert( nData+nReq<=pWriter->nSize );
-
- /* Append the prefix-compressed term and doclist to the buffer. */
- nData += sqlite3Fts3PutVarint(&pWriter->aData[nData], nPrefix);
- nData += sqlite3Fts3PutVarint(&pWriter->aData[nData], nSuffix);
- memcpy(&pWriter->aData[nData], &zTerm[nPrefix], nSuffix);
- nData += nSuffix;
- nData += sqlite3Fts3PutVarint(&pWriter->aData[nData], nDoclist);
- memcpy(&pWriter->aData[nData], aDoclist, nDoclist);
- pWriter->nData = nData + nDoclist;
-
- /* Save the current term so that it can be used to prefix-compress the next.
- ** If the isCopyTerm parameter is true, then the buffer pointed to by
- ** zTerm is transient, so take a copy of the term data. Otherwise, just
- ** store a copy of the pointer.
- */
- if( isCopyTerm ){
- if( nTerm>pWriter->nMalloc ){
- char *zNew = sqlite3_realloc(pWriter->zMalloc, nTerm*2);
- if( !zNew ){
- return SQLITE_NOMEM;
- }
- pWriter->nMalloc = nTerm*2;
- pWriter->zMalloc = zNew;
- pWriter->zTerm = zNew;
- }
- assert( pWriter->zTerm==pWriter->zMalloc );
- memcpy(pWriter->zTerm, zTerm, nTerm);
- }else{
- pWriter->zTerm = (char *)zTerm;
- }
- pWriter->nTerm = nTerm;
-
- return SQLITE_OK;
-}
-
-/*
-** Flush all data associated with the SegmentWriter object pWriter to the
-** 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 */
- int nRoot = 0; /* Size of buffer zRoot */
-
- iLastLeaf = pWriter->iFree;
- rc = fts3WriteSegment(p, pWriter->iFree++, pWriter->aData, pWriter->nData);
- if( rc==SQLITE_OK ){
- rc = fts3NodeWrite(p, pWriter->pTree, 1,
- pWriter->iFirst, pWriter->iFree, &iLast, &zRoot, &nRoot);
- }
- if( rc==SQLITE_OK ){
- rc = fts3WriteSegdir(p, iLevel, iIdx,
- pWriter->iFirst, iLastLeaf, iLast, pWriter->nLeafData, zRoot, nRoot);
- }
- }else{
- /* The entire tree fits on the root node. Write it to the segdir table. */
- rc = fts3WriteSegdir(p, iLevel, iIdx,
- 0, 0, 0, pWriter->nLeafData, pWriter->aData, pWriter->nData);
- }
- p->nLeafAdd++;
- return rc;
-}
-
-/*
-** Release all memory held by the SegmentWriter object passed as the
-** first argument.
-*/
-static void fts3SegWriterFree(SegmentWriter *pWriter){
- if( pWriter ){
- sqlite3_free(pWriter->aData);
- sqlite3_free(pWriter->zMalloc);
- fts3NodeFree(pWriter->pTree);
- sqlite3_free(pWriter);
- }
-}
-
-/*
-** The first value in the apVal[] array is assumed to contain an integer.
-** This function tests if there exist any documents with docid values that
-** are different from that integer. i.e. if deleting the document with docid
-** pRowid would mean the FTS3 table were empty.
-**
-** If successful, *pisEmpty is set to true if the table is empty except for
-** document pRowid, or false otherwise, and SQLITE_OK is returned. If an
-** error occurs, an SQLite error code is returned.
-*/
-static int fts3IsEmpty(Fts3Table *p, sqlite3_value *pRowid, int *pisEmpty){
- sqlite3_stmt *pStmt;
- int rc;
- if( p->zContentTbl ){
- /* If using the content=xxx option, assume the table is never empty */
- *pisEmpty = 0;
- rc = SQLITE_OK;
- }else{
- rc = fts3SqlStmt(p, SQL_IS_EMPTY, &pStmt, &pRowid);
- if( rc==SQLITE_OK ){
- if( SQLITE_ROW==sqlite3_step(pStmt) ){
- *pisEmpty = sqlite3_column_int(pStmt, 0);
- }
- rc = sqlite3_reset(pStmt);
- }
- }
- return rc;
-}
-
-/*
-** Set *pnMax to the largest segment level in the database for the index
-** iIndex.
-**
-** Segment levels are stored in the 'level' column of the %_segdir table.
-**
-** 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);
-}
-
-/*
-** iAbsLevel is an absolute level that may be assumed to exist within
-** the database. This function checks if it is the largest level number
-** within its index. Assuming no error occurs, *pbMax is set to 1 if
-** iAbsLevel is indeed the largest level, or 0 otherwise, and SQLITE_OK
-** is returned. If an error occurs, an error code is returned and the
-** final value of *pbMax is undefined.
-*/
-static int fts3SegmentIsMaxLevel(Fts3Table *p, i64 iAbsLevel, int *pbMax){
-
- /* 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).
- */
- sqlite3_stmt *pStmt;
- int rc = fts3SqlStmt(p, SQL_SELECT_SEGDIR_MAX_LEVEL, &pStmt, 0);
- if( rc!=SQLITE_OK ) return rc;
- sqlite3_bind_int64(pStmt, 1, iAbsLevel+1);
- sqlite3_bind_int64(pStmt, 2,
- ((iAbsLevel/FTS3_SEGDIR_MAXLEVEL)+1) * FTS3_SEGDIR_MAXLEVEL
- );
-
- *pbMax = 0;
- if( SQLITE_ROW==sqlite3_step(pStmt) ){
- *pbMax = sqlite3_column_type(pStmt, 0)==SQLITE_NULL;
- }
- return sqlite3_reset(pStmt);
-}
-
-/*
-** Delete all entries in the %_segments table associated with the segment
-** opened with seg-reader pSeg. This function does not affect the contents
-** of the %_segdir table.
-*/
-static int fts3DeleteSegment(
- Fts3Table *p, /* FTS table handle */
- Fts3SegReader *pSeg /* Segment to delete */
-){
- int rc = SQLITE_OK; /* Return code */
- if( pSeg->iStartBlock ){
- sqlite3_stmt *pDelete; /* SQL statement to delete rows */
- rc = fts3SqlStmt(p, SQL_DELETE_SEGMENTS_RANGE, &pDelete, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pDelete, 1, pSeg->iStartBlock);
- sqlite3_bind_int64(pDelete, 2, pSeg->iEndBlock);
- sqlite3_step(pDelete);
- rc = sqlite3_reset(pDelete);
- }
- }
- return rc;
-}
-
-/*
-** This function is used after merging multiple segments into a single large
-** segment to delete the old, now redundant, segment b-trees. Specifically,
-** it:
-**
-** 1) Deletes all %_segments entries for the segments associated with
-** each of the SegReader objects in the array passed as the third
-** argument, and
-**
-** 2) deletes all %_segdir entries with level iLevel, or all %_segdir
-** entries regardless of level if (iLevel<0).
-**
-** SQLITE_OK is returned if successful, otherwise an SQLite error code.
-*/
-static int fts3DeleteSegdir(
- Fts3Table *p, /* Virtual table handle */
- int iLangid, /* Language id */
- int iIndex, /* Index for p->aIndex */
- int iLevel, /* Level of %_segdir entries to delete */
- Fts3SegReader **apSegment, /* Array of SegReader objects */
- int nReader /* Size of array apSegment */
-){
- int rc = SQLITE_OK; /* Return Code */
- int i; /* Iterator variable */
- sqlite3_stmt *pDelete = 0; /* SQL statement to delete rows */
-
- for(i=0; rc==SQLITE_OK && i<nReader; i++){
- rc = fts3DeleteSegment(p, apSegment[i]);
- }
- if( rc!=SQLITE_OK ){
- 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);
- }
-
- return rc;
-}
-
-/*
-** When this function is called, buffer *ppList (size *pnList bytes) contains
-** a position list that may (or may not) feature multiple columns. This
-** function adjusts the pointer *ppList and the length *pnList so that they
-** identify the subset of the position list that corresponds to column iCol.
-**
-** If there are no entries in the input position list for column iCol, then
-** *pnList is set to zero before returning.
-**
-** If parameter bZero is non-zero, then any part of the input list following
-** the end of the output list is zeroed before returning.
-*/
-static void fts3ColumnFilter(
- int iCol, /* Column to filter on */
- int bZero, /* Zero out anything following *ppList */
- char **ppList, /* IN/OUT: Pointer to position list */
- int *pnList /* IN/OUT: Size of buffer *ppList in bytes */
-){
- char *pList = *ppList;
- int nList = *pnList;
- char *pEnd = &pList[nList];
- int iCurrent = 0;
- char *p = pList;
-
- assert( iCol>=0 );
- while( 1 ){
- char c = 0;
- while( p<pEnd && (c | *p)&0xFE ) c = *p++ & 0x80;
-
- if( iCol==iCurrent ){
- nList = (int)(p - pList);
- break;
- }
-
- nList -= (int)(p - pList);
- pList = p;
- if( nList==0 ){
- break;
- }
- p = &pList[1];
- p += fts3GetVarint32(p, &iCurrent);
- }
-
- if( bZero && &pList[nList]!=pEnd ){
- memset(&pList[nList], 0, pEnd - &pList[nList]);
- }
- *ppList = pList;
- *pnList = nList;
-}
-
-/*
-** Cache data in the Fts3MultiSegReader.aBuffer[] buffer (overwriting any
-** existing data). Grow the buffer if required.
-**
-** If successful, return SQLITE_OK. Otherwise, if an OOM error is encountered
-** trying to resize the buffer, return SQLITE_NOMEM.
-*/
-static int fts3MsrBufferData(
- Fts3MultiSegReader *pMsr, /* Multi-segment-reader handle */
- char *pList,
- int nList
-){
- if( nList>pMsr->nBuffer ){
- char *pNew;
- pMsr->nBuffer = nList*2;
- pNew = (char *)sqlite3_realloc(pMsr->aBuffer, pMsr->nBuffer);
- if( !pNew ) return SQLITE_NOMEM;
- pMsr->aBuffer = pNew;
- }
-
- memcpy(pMsr->aBuffer, pList, nList);
- return SQLITE_OK;
-}
-
-int sqlite3Fts3MsrIncrNext(
- Fts3Table *p, /* Virtual table handle */
- Fts3MultiSegReader *pMsr, /* Multi-segment-reader handle */
- sqlite3_int64 *piDocid, /* OUT: Docid value */
- char **paPoslist, /* OUT: Pointer to position list */
- int *pnPoslist /* OUT: Size of position list in bytes */
-){
- int nMerge = pMsr->nAdvance;
- Fts3SegReader **apSegment = pMsr->apSegment;
- int (*xCmp)(Fts3SegReader *, Fts3SegReader *) = (
- p->bDescIdx ? fts3SegReaderDoclistCmpRev : fts3SegReaderDoclistCmp
- );
-
- if( nMerge==0 ){
- *paPoslist = 0;
- return SQLITE_OK;
- }
-
- while( 1 ){
- Fts3SegReader *pSeg;
- pSeg = pMsr->apSegment[0];
-
- if( pSeg->pOffsetList==0 ){
- *paPoslist = 0;
- break;
- }else{
- int rc;
- char *pList;
- int nList;
- int j;
- sqlite3_int64 iDocid = apSegment[0]->iDocid;
-
- rc = fts3SegReaderNextDocid(p, apSegment[0], &pList, &nList);
- j = 1;
- while( rc==SQLITE_OK
- && j<nMerge
- && apSegment[j]->pOffsetList
- && apSegment[j]->iDocid==iDocid
- ){
- rc = fts3SegReaderNextDocid(p, apSegment[j], 0, 0);
- j++;
- }
- if( rc!=SQLITE_OK ) return rc;
- fts3SegReaderSort(pMsr->apSegment, nMerge, j, xCmp);
-
- if( nList>0 && fts3SegReaderIsPending(apSegment[0]) ){
- rc = fts3MsrBufferData(pMsr, pList, nList+1);
- if( rc!=SQLITE_OK ) return rc;
- assert( (pMsr->aBuffer[nList] & 0xFE)==0x00 );
- pList = pMsr->aBuffer;
- }
-
- if( pMsr->iColFilter>=0 ){
- fts3ColumnFilter(pMsr->iColFilter, 1, &pList, &nList);
- }
-
- if( nList>0 ){
- *paPoslist = pList;
- *piDocid = iDocid;
- *pnPoslist = nList;
- break;
- }
- }
- }
-
- return SQLITE_OK;
-}
-
-static int fts3SegReaderStart(
- Fts3Table *p, /* Virtual table handle */
- Fts3MultiSegReader *pCsr, /* Cursor object */
- const char *zTerm, /* Term searched for (or NULL) */
- int nTerm /* Length of zTerm in bytes */
-){
- int i;
- int nSeg = pCsr->nSegment;
-
- /* If the Fts3SegFilter defines a specific term (or term prefix) to search
- ** for, then advance each segment iterator until it points to a term of
- ** equal or greater value than the specified term. This prevents many
- ** unnecessary merge/sort operations for the case where single segment
- ** b-tree leaf nodes contain more than one term.
- */
- for(i=0; pCsr->bRestart==0 && i<pCsr->nSegment; i++){
- int res = 0;
- Fts3SegReader *pSeg = pCsr->apSegment[i];
- do {
- int rc = fts3SegReaderNext(p, pSeg, 0);
- if( rc!=SQLITE_OK ) return rc;
- }while( zTerm && (res = fts3SegReaderTermCmp(pSeg, zTerm, nTerm))<0 );
-
- if( pSeg->bLookup && res!=0 ){
- fts3SegReaderSetEof(pSeg);
- }
- }
- fts3SegReaderSort(pCsr->apSegment, nSeg, nSeg, fts3SegReaderCmp);
-
- return SQLITE_OK;
-}
-
-int sqlite3Fts3SegReaderStart(
- Fts3Table *p, /* Virtual table handle */
- Fts3MultiSegReader *pCsr, /* Cursor object */
- Fts3SegFilter *pFilter /* Restrictions on range of iteration */
-){
- pCsr->pFilter = pFilter;
- return fts3SegReaderStart(p, pCsr, pFilter->zTerm, pFilter->nTerm);
-}
-
-int sqlite3Fts3MsrIncrStart(
- Fts3Table *p, /* Virtual table handle */
- Fts3MultiSegReader *pCsr, /* Cursor object */
- int iCol, /* Column to match on. */
- const char *zTerm, /* Term to iterate through a doclist for */
- int nTerm /* Number of bytes in zTerm */
-){
- int i;
- int rc;
- int nSegment = pCsr->nSegment;
- int (*xCmp)(Fts3SegReader *, Fts3SegReader *) = (
- p->bDescIdx ? fts3SegReaderDoclistCmpRev : fts3SegReaderDoclistCmp
- );
-
- assert( pCsr->pFilter==0 );
- assert( zTerm && nTerm>0 );
-
- /* Advance each segment iterator until it points to the term zTerm/nTerm. */
- rc = fts3SegReaderStart(p, pCsr, zTerm, nTerm);
- if( rc!=SQLITE_OK ) return rc;
-
- /* Determine how many of the segments actually point to zTerm/nTerm. */
- for(i=0; i<nSegment; i++){
- Fts3SegReader *pSeg = pCsr->apSegment[i];
- if( !pSeg->aNode || fts3SegReaderTermCmp(pSeg, zTerm, nTerm) ){
- break;
- }
- }
- pCsr->nAdvance = i;
-
- /* Advance each of the segments to point to the first docid. */
- for(i=0; i<pCsr->nAdvance; i++){
- rc = fts3SegReaderFirstDocid(p, pCsr->apSegment[i]);
- if( rc!=SQLITE_OK ) return rc;
- }
- fts3SegReaderSort(pCsr->apSegment, i, i, xCmp);
-
- assert( iCol<0 || iCol<p->nColumn );
- pCsr->iColFilter = iCol;
-
- return SQLITE_OK;
-}
-
-/*
-** This function is called on a MultiSegReader that has been started using
-** sqlite3Fts3MsrIncrStart(). One or more calls to MsrIncrNext() may also
-** have been made. Calling this function puts the MultiSegReader in such
-** a state that if the next two calls are:
-**
-** sqlite3Fts3SegReaderStart()
-** sqlite3Fts3SegReaderStep()
-**
-** then the entire doclist for the term is available in
-** MultiSegReader.aDoclist/nDoclist.
-*/
-int sqlite3Fts3MsrIncrRestart(Fts3MultiSegReader *pCsr){
- int i; /* Used to iterate through segment-readers */
-
- assert( pCsr->zTerm==0 );
- assert( pCsr->nTerm==0 );
- assert( pCsr->aDoclist==0 );
- assert( pCsr->nDoclist==0 );
-
- pCsr->nAdvance = 0;
- pCsr->bRestart = 1;
- for(i=0; i<pCsr->nSegment; i++){
- pCsr->apSegment[i]->pOffsetList = 0;
- pCsr->apSegment[i]->nOffsetList = 0;
- pCsr->apSegment[i]->iDocid = 0;
- }
-
- return SQLITE_OK;
-}
-
-
-int sqlite3Fts3SegReaderStep(
- Fts3Table *p, /* Virtual table handle */
- Fts3MultiSegReader *pCsr /* Cursor object */
-){
- int rc = SQLITE_OK;
-
- int isIgnoreEmpty = (pCsr->pFilter->flags & FTS3_SEGMENT_IGNORE_EMPTY);
- int isRequirePos = (pCsr->pFilter->flags & FTS3_SEGMENT_REQUIRE_POS);
- int isColFilter = (pCsr->pFilter->flags & FTS3_SEGMENT_COLUMN_FILTER);
- int isPrefix = (pCsr->pFilter->flags & FTS3_SEGMENT_PREFIX);
- int isScan = (pCsr->pFilter->flags & FTS3_SEGMENT_SCAN);
- int isFirst = (pCsr->pFilter->flags & FTS3_SEGMENT_FIRST);
-
- Fts3SegReader **apSegment = pCsr->apSegment;
- int nSegment = pCsr->nSegment;
- Fts3SegFilter *pFilter = pCsr->pFilter;
- int (*xCmp)(Fts3SegReader *, Fts3SegReader *) = (
- p->bDescIdx ? fts3SegReaderDoclistCmpRev : fts3SegReaderDoclistCmp
- );
-
- if( pCsr->nSegment==0 ) return SQLITE_OK;
-
- do {
- int nMerge;
- int i;
-
- /* Advance the first pCsr->nAdvance entries in the apSegment[] array
- ** forward. Then sort the list in order of current term again.
- */
- for(i=0; i<pCsr->nAdvance; i++){
- Fts3SegReader *pSeg = apSegment[i];
- if( pSeg->bLookup ){
- fts3SegReaderSetEof(pSeg);
- }else{
- rc = fts3SegReaderNext(p, pSeg, 0);
- }
- if( rc!=SQLITE_OK ) return rc;
- }
- fts3SegReaderSort(apSegment, nSegment, pCsr->nAdvance, fts3SegReaderCmp);
- pCsr->nAdvance = 0;
-
- /* If all the seg-readers are at EOF, we're finished. return SQLITE_OK. */
- assert( rc==SQLITE_OK );
- if( apSegment[0]->aNode==0 ) break;
-
- pCsr->nTerm = apSegment[0]->nTerm;
- pCsr->zTerm = apSegment[0]->zTerm;
-
- /* If this is a prefix-search, and if the term that apSegment[0] points
- ** to does not share a suffix with pFilter->zTerm/nTerm, then all
- ** required callbacks have been made. In this case exit early.
- **
- ** Similarly, if this is a search for an exact match, and the first term
- ** of segment apSegment[0] is not a match, exit early.
- */
- if( pFilter->zTerm && !isScan ){
- if( pCsr->nTerm<pFilter->nTerm
- || (!isPrefix && pCsr->nTerm>pFilter->nTerm)
- || memcmp(pCsr->zTerm, pFilter->zTerm, pFilter->nTerm)
- ){
- break;
- }
- }
-
- nMerge = 1;
- while( nMerge<nSegment
- && apSegment[nMerge]->aNode
- && apSegment[nMerge]->nTerm==pCsr->nTerm
- && 0==memcmp(pCsr->zTerm, apSegment[nMerge]->zTerm, pCsr->nTerm)
- ){
- nMerge++;
- }
-
- assert( isIgnoreEmpty || (isRequirePos && !isColFilter) );
- if( nMerge==1
- && !isIgnoreEmpty
- && !isFirst
- && (p->bDescIdx==0 || fts3SegReaderIsPending(apSegment[0])==0)
- ){
- pCsr->nDoclist = apSegment[0]->nDoclist;
- if( fts3SegReaderIsPending(apSegment[0]) ){
- rc = fts3MsrBufferData(pCsr, apSegment[0]->aDoclist, pCsr->nDoclist);
- pCsr->aDoclist = pCsr->aBuffer;
- }else{
- pCsr->aDoclist = apSegment[0]->aDoclist;
- }
- if( rc==SQLITE_OK ) rc = SQLITE_ROW;
- }else{
- int nDoclist = 0; /* Size of doclist */
- sqlite3_int64 iPrev = 0; /* Previous docid stored in doclist */
-
- /* The current term of the first nMerge entries in the array
- ** of Fts3SegReader objects is the same. The doclists must be merged
- ** and a single term returned with the merged doclist.
- */
- for(i=0; i<nMerge; i++){
- fts3SegReaderFirstDocid(p, apSegment[i]);
- }
- fts3SegReaderSort(apSegment, nMerge, nMerge, xCmp);
- while( apSegment[0]->pOffsetList ){
- int j; /* Number of segments that share a docid */
- char *pList = 0;
- int nList = 0;
- int nByte;
- sqlite3_int64 iDocid = apSegment[0]->iDocid;
- fts3SegReaderNextDocid(p, apSegment[0], &pList, &nList);
- j = 1;
- while( j<nMerge
- && apSegment[j]->pOffsetList
- && apSegment[j]->iDocid==iDocid
- ){
- fts3SegReaderNextDocid(p, apSegment[j], 0, 0);
- j++;
- }
-
- if( isColFilter ){
- fts3ColumnFilter(pFilter->iCol, 0, &pList, &nList);
- }
-
- if( !isIgnoreEmpty || nList>0 ){
-
- /* Calculate the 'docid' delta value to write into the merged
- ** doclist. */
- sqlite3_int64 iDelta;
- if( p->bDescIdx && nDoclist>0 ){
- iDelta = iPrev - iDocid;
- }else{
- iDelta = iDocid - iPrev;
- }
- assert( iDelta>0 || (nDoclist==0 && iDelta==iDocid) );
- assert( nDoclist>0 || iDelta==iDocid );
-
- nByte = sqlite3Fts3VarintLen(iDelta) + (isRequirePos?nList+1:0);
- if( nDoclist+nByte>pCsr->nBuffer ){
- char *aNew;
- pCsr->nBuffer = (nDoclist+nByte)*2;
- aNew = sqlite3_realloc(pCsr->aBuffer, pCsr->nBuffer);
- if( !aNew ){
- return SQLITE_NOMEM;
- }
- pCsr->aBuffer = aNew;
- }
-
- if( isFirst ){
- char *a = &pCsr->aBuffer[nDoclist];
- int nWrite;
-
- nWrite = sqlite3Fts3FirstFilter(iDelta, pList, nList, a);
- if( nWrite ){
- iPrev = iDocid;
- nDoclist += nWrite;
- }
- }else{
- nDoclist += sqlite3Fts3PutVarint(&pCsr->aBuffer[nDoclist], iDelta);
- iPrev = iDocid;
- if( isRequirePos ){
- memcpy(&pCsr->aBuffer[nDoclist], pList, nList);
- nDoclist += nList;
- pCsr->aBuffer[nDoclist++] = '\0';
- }
- }
- }
-
- fts3SegReaderSort(apSegment, nMerge, j, xCmp);
- }
- if( nDoclist>0 ){
- pCsr->aDoclist = pCsr->aBuffer;
- pCsr->nDoclist = nDoclist;
- rc = SQLITE_ROW;
- }
- }
- pCsr->nAdvance = nMerge;
- }while( rc==SQLITE_OK );
-
- return rc;
-}
-
-
-void sqlite3Fts3SegReaderFinish(
- Fts3MultiSegReader *pCsr /* Cursor object */
-){
- if( pCsr ){
- int i;
- for(i=0; i<pCsr->nSegment; i++){
- sqlite3Fts3SegReaderFree(pCsr->apSegment[i]);
- }
- sqlite3_free(pCsr->apSegment);
- sqlite3_free(pCsr->aBuffer);
-
- pCsr->nSegment = 0;
- pCsr->apSegment = 0;
- pCsr->aBuffer = 0;
- }
-}
-
-/*
-** Decode the "end_block" field, selected by column iCol of the SELECT
-** statement passed as the first argument.
-**
-** The "end_block" field may contain either an integer, or a text field
-** containing the text representation of two non-negative integers separated
-** by one or more space (0x20) characters. In the first case, set *piEndBlock
-** to the integer value and *pnByte to zero before returning. In the second,
-** set *piEndBlock to the first value and *pnByte to the second.
-*/
-static void fts3ReadEndBlockField(
- sqlite3_stmt *pStmt,
- int iCol,
- i64 *piEndBlock,
- i64 *pnByte
-){
- const unsigned char *zText = sqlite3_column_text(pStmt, iCol);
- if( zText ){
- int i;
- int iMul = 1;
- i64 iVal = 0;
- for(i=0; zText[i]>='0' && zText[i]<='9'; i++){
- iVal = iVal*10 + (zText[i] - '0');
- }
- *piEndBlock = iVal;
- while( zText[i]==' ' ) i++;
- iVal = 0;
- if( zText[i]=='-' ){
- i++;
- iMul = -1;
- }
- for(/* no-op */; zText[i]>='0' && zText[i]<='9'; i++){
- iVal = iVal*10 + (zText[i] - '0');
- }
- *pnByte = (iVal * (i64)iMul);
- }
-}
-
-
-/*
-** A segment of size nByte bytes has just been written to absolute level
-** iAbsLevel. Promote any segments that should be promoted as a result.
-*/
-static int fts3PromoteSegments(
- Fts3Table *p, /* FTS table handle */
- sqlite3_int64 iAbsLevel, /* Absolute level just updated */
- sqlite3_int64 nByte /* Size of new segment at iAbsLevel */
-){
- int rc = SQLITE_OK;
- sqlite3_stmt *pRange;
-
- rc = fts3SqlStmt(p, SQL_SELECT_LEVEL_RANGE2, &pRange, 0);
-
- if( rc==SQLITE_OK ){
- int bOk = 0;
- i64 iLast = (iAbsLevel/FTS3_SEGDIR_MAXLEVEL + 1) * FTS3_SEGDIR_MAXLEVEL - 1;
- i64 nLimit = (nByte*3)/2;
-
- /* Loop through all entries in the %_segdir table corresponding to
- ** segments in this index on levels greater than iAbsLevel. If there is
- ** at least one such segment, and it is possible to determine that all
- ** such segments are smaller than nLimit bytes in size, they will be
- ** promoted to level iAbsLevel. */
- sqlite3_bind_int64(pRange, 1, iAbsLevel+1);
- sqlite3_bind_int64(pRange, 2, iLast);
- while( SQLITE_ROW==sqlite3_step(pRange) ){
- i64 nSize = 0, dummy;
- fts3ReadEndBlockField(pRange, 2, &dummy, &nSize);
- if( nSize<=0 || nSize>nLimit ){
- /* If nSize==0, then the %_segdir.end_block field does not not
- ** contain a size value. This happens if it was written by an
- ** old version of FTS. In this case it is not possible to determine
- ** the size of the segment, and so segment promotion does not
- ** take place. */
- bOk = 0;
- break;
- }
- bOk = 1;
- }
- rc = sqlite3_reset(pRange);
-
- if( bOk ){
- int iIdx = 0;
- sqlite3_stmt *pUpdate1;
- sqlite3_stmt *pUpdate2;
-
- if( rc==SQLITE_OK ){
- rc = fts3SqlStmt(p, SQL_UPDATE_LEVEL_IDX, &pUpdate1, 0);
- }
- if( rc==SQLITE_OK ){
- rc = fts3SqlStmt(p, SQL_UPDATE_LEVEL, &pUpdate2, 0);
- }
-
- if( rc==SQLITE_OK ){
-
- /* Loop through all %_segdir entries for segments in this index with
- ** levels equal to or greater than iAbsLevel. As each entry is visited,
- ** updated it to set (level = -1) and (idx = N), where N is 0 for the
- ** oldest segment in the range, 1 for the next oldest, and so on.
- **
- ** In other words, move all segments being promoted to level -1,
- ** setting the "idx" fields as appropriate to keep them in the same
- ** order. The contents of level -1 (which is never used, except
- ** transiently here), will be moved back to level iAbsLevel below. */
- sqlite3_bind_int64(pRange, 1, iAbsLevel);
- while( SQLITE_ROW==sqlite3_step(pRange) ){
- sqlite3_bind_int(pUpdate1, 1, iIdx++);
- sqlite3_bind_int(pUpdate1, 2, sqlite3_column_int(pRange, 0));
- sqlite3_bind_int(pUpdate1, 3, sqlite3_column_int(pRange, 1));
- sqlite3_step(pUpdate1);
- rc = sqlite3_reset(pUpdate1);
- if( rc!=SQLITE_OK ){
- sqlite3_reset(pRange);
- break;
- }
- }
- }
- if( rc==SQLITE_OK ){
- rc = sqlite3_reset(pRange);
- }
-
- /* Move level -1 to level iAbsLevel */
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pUpdate2, 1, iAbsLevel);
- sqlite3_step(pUpdate2);
- rc = sqlite3_reset(pUpdate2);
- }
- }
- }
-
-
- return rc;
-}
-
-/*
-** Merge all level iLevel segments in the database into a single
-** iLevel+1 segment. Or, if iLevel<0, merge all segments into a
-** single segment with a level equal to the numerically largest level
-** currently present in the database.
-**
-** If this function is called with iLevel<0, but there is only one
-** segment in the database, SQLITE_DONE is returned immediately.
-** Otherwise, if successful, SQLITE_OK is returned. If an error occurs,
-** an SQLite error code is returned.
-*/
-static int fts3SegmentMerge(
- 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 */
- i64 iMaxLevel = 0; /* Max level number for this index/langid */
-
- assert( iLevel==FTS3_SEGCURSOR_ALL
- || iLevel==FTS3_SEGCURSOR_PENDING
- || iLevel>=0
- );
- assert( iLevel<FTS3_SEGDIR_MAXLEVEL );
- assert( iIndex>=0 && iIndex<p->nIndex );
-
- rc = sqlite3Fts3SegReaderCursor(p, iLangid, iIndex, iLevel, 0, 0, 1, 0, &csr);
- if( rc!=SQLITE_OK || csr.nSegment==0 ) goto finished;
-
- if( iLevel!=FTS3_SEGCURSOR_PENDING ){
- rc = fts3SegmentMaxLevel(p, iLangid, iIndex, &iMaxLevel);
- if( rc!=SQLITE_OK ) goto finished;
- }
-
- if( iLevel==FTS3_SEGCURSOR_ALL ){
- /* This call is to merge all segments in the database to a single
- ** segment. The level of the new segment is equal to the numerically
- ** greatest segment level currently present in the database for this
- ** index. The idx of the new segment is always 0. */
- if( csr.nSegment==1 ){
- rc = SQLITE_DONE;
- goto finished;
- }
- iNewLevel = iMaxLevel;
- bIgnoreEmpty = 1;
-
- }else{
- /* This call is to merge all segments at level iLevel. find the next
- ** available segment index at level iLevel+1. The call to
- ** fts3AllocateSegdirIdx() will merge the segments at level iLevel+1 to
- ** a single iLevel+2 segment if necessary. */
- assert( FTS3_SEGCURSOR_PENDING==-1 );
- iNewLevel = getAbsoluteLevel(p, iLangid, iIndex, iLevel+1);
- rc = fts3AllocateSegdirIdx(p, iLangid, iIndex, iLevel+1, &iIdx);
- bIgnoreEmpty = (iLevel!=FTS3_SEGCURSOR_PENDING) && (iNewLevel>iMaxLevel);
- }
- if( rc!=SQLITE_OK ) goto finished;
-
- assert( csr.nSegment>0 );
- assert( iNewLevel>=getAbsoluteLevel(p, iLangid, iIndex, 0) );
- assert( iNewLevel<getAbsoluteLevel(p, iLangid, iIndex,FTS3_SEGDIR_MAXLEVEL) );
-
- memset(&filter, 0, sizeof(Fts3SegFilter));
- filter.flags = FTS3_SEGMENT_REQUIRE_POS;
- filter.flags |= (bIgnoreEmpty ? FTS3_SEGMENT_IGNORE_EMPTY : 0);
-
- rc = sqlite3Fts3SegReaderStart(p, &csr, &filter);
- while( SQLITE_OK==rc ){
- rc = sqlite3Fts3SegReaderStep(p, &csr);
- if( rc!=SQLITE_ROW ) break;
- rc = fts3SegWriterAdd(p, &pWriter, 1,
- csr.zTerm, csr.nTerm, csr.aDoclist, csr.nDoclist);
- }
- if( rc!=SQLITE_OK ) goto finished;
- assert( pWriter || bIgnoreEmpty );
-
- if( iLevel!=FTS3_SEGCURSOR_PENDING ){
- rc = fts3DeleteSegdir(
- p, iLangid, iIndex, iLevel, csr.apSegment, csr.nSegment
- );
- if( rc!=SQLITE_OK ) goto finished;
- }
- if( pWriter ){
- rc = fts3SegWriterFlush(p, pWriter, iNewLevel, iIdx);
- if( rc==SQLITE_OK ){
- if( iLevel==FTS3_SEGCURSOR_PENDING || iNewLevel<iMaxLevel ){
- rc = fts3PromoteSegments(p, iNewLevel, pWriter->nLeafData);
- }
- }
- }
-
- finished:
- fts3SegWriterFree(pWriter);
- sqlite3Fts3SegReaderFinish(&csr);
- return rc;
-}
-
-
-/*
-** Flush the contents of pendingTerms to level 0 segments.
-*/
-int sqlite3Fts3PendingTermsFlush(Fts3Table *p){
- int rc = SQLITE_OK;
- int i;
-
- for(i=0; rc==SQLITE_OK && i<p->nIndex; i++){
- rc = fts3SegmentMerge(p, p->iPrevLangid, i, FTS3_SEGCURSOR_PENDING);
- if( rc==SQLITE_DONE ) rc = SQLITE_OK;
- }
- sqlite3Fts3PendingTermsClear(p);
-
- /* Determine the auto-incr-merge setting if unknown. If enabled,
- ** estimate the number of leaf blocks of content to be written
- */
- if( rc==SQLITE_OK && p->bHasStat
- && p->nAutoincrmerge==0xff && p->nLeafAdd>0
- ){
- sqlite3_stmt *pStmt = 0;
- rc = fts3SqlStmt(p, SQL_SELECT_STAT, &pStmt, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int(pStmt, 1, FTS_STAT_AUTOINCRMERGE);
- rc = sqlite3_step(pStmt);
- if( rc==SQLITE_ROW ){
- p->nAutoincrmerge = sqlite3_column_int(pStmt, 0);
- if( p->nAutoincrmerge==1 ) p->nAutoincrmerge = 8;
- }else if( rc==SQLITE_DONE ){
- p->nAutoincrmerge = 0;
- }
- rc = sqlite3_reset(pStmt);
- }
- }
- return rc;
-}
-
-/*
-** Encode N integers as varints into a blob.
-*/
-static void fts3EncodeIntArray(
- int N, /* The number of integers to encode */
- u32 *a, /* The integer values */
- char *zBuf, /* Write the BLOB here */
- int *pNBuf /* Write number of bytes if zBuf[] used here */
-){
- int i, j;
- for(i=j=0; i<N; i++){
- j += sqlite3Fts3PutVarint(&zBuf[j], (sqlite3_int64)a[i]);
- }
- *pNBuf = j;
-}
-
-/*
-** Decode a blob of varints into N integers
-*/
-static void fts3DecodeIntArray(
- int N, /* The number of integers to decode */
- u32 *a, /* Write the integer values */
- const char *zBuf, /* The BLOB containing the varints */
- int nBuf /* size of the BLOB */
-){
- int i, j;
- UNUSED_PARAMETER(nBuf);
- for(i=j=0; i<N; i++){
- sqlite3_int64 x;
- j += sqlite3Fts3GetVarint(&zBuf[j], &x);
- assert(j<=nBuf);
- a[i] = (u32)(x & 0xffffffff);
- }
-}
-
-/*
-** Insert the sizes (in tokens) for each column of the document
-** with docid equal to p->iPrevDocid. The sizes are encoded as
-** a blob of varints.
-*/
-static void fts3InsertDocsize(
- int *pRC, /* Result code */
- Fts3Table *p, /* Table into which to insert */
- u32 *aSz /* Sizes of each column, in tokens */
-){
- char *pBlob; /* The BLOB encoding of the document size */
- int nBlob; /* Number of bytes in the BLOB */
- sqlite3_stmt *pStmt; /* Statement used to insert the encoding */
- int rc; /* Result code from subfunctions */
-
- if( *pRC ) return;
- pBlob = sqlite3_malloc( 10*p->nColumn );
- if( pBlob==0 ){
- *pRC = SQLITE_NOMEM;
- return;
- }
- fts3EncodeIntArray(p->nColumn, aSz, pBlob, &nBlob);
- rc = fts3SqlStmt(p, SQL_REPLACE_DOCSIZE, &pStmt, 0);
- if( rc ){
- sqlite3_free(pBlob);
- *pRC = rc;
- return;
- }
- sqlite3_bind_int64(pStmt, 1, p->iPrevDocid);
- sqlite3_bind_blob(pStmt, 2, pBlob, nBlob, sqlite3_free);
- sqlite3_step(pStmt);
- *pRC = sqlite3_reset(pStmt);
-}
-
-/*
-** Record 0 of the %_stat table contains a blob consisting of N varints,
-** where N is the number of user defined columns in the fts3 table plus
-** two. If nCol is the number of user defined columns, then values of the
-** varints are set as follows:
-**
-** Varint 0: Total number of rows in the table.
-**
-** Varint 1..nCol: For each column, the total number of tokens stored in
-** the column for all rows of the table.
-**
-** Varint 1+nCol: The total size, in bytes, of all text values in all
-** columns of all rows of the table.
-**
-*/
-static void fts3UpdateDocTotals(
- int *pRC, /* The result code */
- Fts3Table *p, /* Table being updated */
- u32 *aSzIns, /* Size increases */
- u32 *aSzDel, /* Size decreases */
- int nChng /* Change in the number of documents */
-){
- char *pBlob; /* Storage for BLOB written into %_stat */
- int nBlob; /* Size of BLOB written into %_stat */
- u32 *a; /* Array of integers that becomes the BLOB */
- sqlite3_stmt *pStmt; /* Statement for reading and writing */
- int i; /* Loop counter */
- int rc; /* Result code from subfunctions */
-
- const int nStat = p->nColumn+2;
-
- if( *pRC ) return;
- a = sqlite3_malloc( (sizeof(u32)+10)*nStat );
- if( a==0 ){
- *pRC = SQLITE_NOMEM;
- return;
- }
- pBlob = (char*)&a[nStat];
- rc = fts3SqlStmt(p, SQL_SELECT_STAT, &pStmt, 0);
- if( rc ){
- sqlite3_free(a);
- *pRC = rc;
- return;
- }
- sqlite3_bind_int(pStmt, 1, FTS_STAT_DOCTOTAL);
- if( sqlite3_step(pStmt)==SQLITE_ROW ){
- fts3DecodeIntArray(nStat, a,
- sqlite3_column_blob(pStmt, 0),
- sqlite3_column_bytes(pStmt, 0));
- }else{
- memset(a, 0, sizeof(u32)*(nStat) );
- }
- rc = sqlite3_reset(pStmt);
- if( rc!=SQLITE_OK ){
- sqlite3_free(a);
- *pRC = rc;
- return;
- }
- if( nChng<0 && a[0]<(u32)(-nChng) ){
- a[0] = 0;
- }else{
- a[0] += nChng;
- }
- for(i=0; i<p->nColumn+1; i++){
- u32 x = a[i+1];
- if( x+aSzIns[i] < aSzDel[i] ){
- x = 0;
- }else{
- x = x + aSzIns[i] - aSzDel[i];
- }
- a[i+1] = x;
- }
- fts3EncodeIntArray(nStat, a, pBlob, &nBlob);
- rc = fts3SqlStmt(p, SQL_REPLACE_STAT, &pStmt, 0);
- if( rc ){
- sqlite3_free(a);
- *pRC = rc;
- return;
- }
- sqlite3_bind_int(pStmt, 1, FTS_STAT_DOCTOTAL);
- sqlite3_bind_blob(pStmt, 2, pBlob, nBlob, SQLITE_STATIC);
- sqlite3_step(pStmt);
- *pRC = sqlite3_reset(pStmt);
- sqlite3_free(a);
-}
-
-/*
-** Merge the entire database so that there is one segment for each
-** iIndex/iLangid combination.
-*/
-static int fts3DoOptimize(Fts3Table *p, int bReturnDone){
- int bSeenDone = 0;
- int rc;
- sqlite3_stmt *pAllLangid = 0;
-
- rc = fts3SqlStmt(p, SQL_SELECT_ALL_LANGID, &pAllLangid, 0);
- if( rc==SQLITE_OK ){
- int rc2;
- sqlite3_bind_int(pAllLangid, 1, p->nIndex);
- while( sqlite3_step(pAllLangid)==SQLITE_ROW ){
- int i;
- int iLangid = sqlite3_column_int(pAllLangid, 0);
- for(i=0; rc==SQLITE_OK && i<p->nIndex; i++){
- rc = fts3SegmentMerge(p, iLangid, i, FTS3_SEGCURSOR_ALL);
- if( rc==SQLITE_DONE ){
- bSeenDone = 1;
- rc = SQLITE_OK;
- }
- }
- }
- rc2 = sqlite3_reset(pAllLangid);
- if( rc==SQLITE_OK ) rc = rc2;
- }
-
- sqlite3Fts3SegmentsClose(p);
- sqlite3Fts3PendingTermsClear(p);
-
- return (rc==SQLITE_OK && bReturnDone && bSeenDone) ? SQLITE_DONE : rc;
-}
-
-/*
-** This function is called when the user executes the following statement:
-**
-** INSERT INTO <tbl>(<tbl>) VALUES('rebuild');
-**
-** The entire FTS index is discarded and rebuilt. If the table is one
-** created using the content=xxx option, then the new index is based on
-** the current contents of the xxx table. Otherwise, it is rebuilt based
-** on the contents of the %_content table.
-*/
-static int fts3DoRebuild(Fts3Table *p){
- int rc; /* Return Code */
-
- rc = fts3DeleteAll(p, 0);
- if( rc==SQLITE_OK ){
- u32 *aSz = 0;
- u32 *aSzIns = 0;
- u32 *aSzDel = 0;
- sqlite3_stmt *pStmt = 0;
- int nEntry = 0;
-
- /* Compose and prepare an SQL statement to loop through the content table */
- char *zSql = sqlite3_mprintf("SELECT %s" , p->zReadExprlist);
- if( !zSql ){
- rc = SQLITE_NOMEM;
- }else{
- rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, 0);
- sqlite3_free(zSql);
- }
-
- if( rc==SQLITE_OK ){
- int nByte = sizeof(u32) * (p->nColumn+1)*3;
- aSz = (u32 *)sqlite3_malloc(nByte);
- if( aSz==0 ){
- rc = SQLITE_NOMEM;
- }else{
- memset(aSz, 0, nByte);
- aSzIns = &aSz[p->nColumn+1];
- aSzDel = &aSzIns[p->nColumn+1];
- }
- }
-
- while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){
- int iCol;
- int iLangid = langidFromSelect(p, pStmt);
- rc = fts3PendingTermsDocid(p, iLangid, sqlite3_column_int64(pStmt, 0));
- memset(aSz, 0, sizeof(aSz[0]) * (p->nColumn+1));
- for(iCol=0; rc==SQLITE_OK && iCol<p->nColumn; iCol++){
- if( p->abNotindexed[iCol]==0 ){
- const char *z = (const char *) sqlite3_column_text(pStmt, iCol+1);
- rc = fts3PendingTermsAdd(p, iLangid, z, iCol, &aSz[iCol]);
- aSz[p->nColumn] += sqlite3_column_bytes(pStmt, iCol+1);
- }
- }
- if( p->bHasDocsize ){
- fts3InsertDocsize(&rc, p, aSz);
- }
- if( rc!=SQLITE_OK ){
- sqlite3_finalize(pStmt);
- pStmt = 0;
- }else{
- nEntry++;
- for(iCol=0; iCol<=p->nColumn; iCol++){
- aSzIns[iCol] += aSz[iCol];
- }
- }
- }
- if( p->bFts4 ){
- fts3UpdateDocTotals(&rc, p, aSzIns, aSzDel, nEntry);
- }
- sqlite3_free(aSz);
-
- if( pStmt ){
- int rc2 = sqlite3_finalize(pStmt);
- if( rc==SQLITE_OK ){
- rc = rc2;
- }
- }
- }
-
- return rc;
-}
-
-
-/*
-** This function opens a cursor used to read the input data for an
-** incremental merge operation. Specifically, it opens a cursor to scan
-** the oldest nSeg segments (idx=0 through idx=(nSeg-1)) in absolute
-** level iAbsLevel.
-*/
-static int fts3IncrmergeCsr(
- Fts3Table *p, /* FTS3 table handle */
- sqlite3_int64 iAbsLevel, /* Absolute level to open */
- int nSeg, /* Number of segments to merge */
- Fts3MultiSegReader *pCsr /* Cursor object to populate */
-){
- int rc; /* Return Code */
- sqlite3_stmt *pStmt = 0; /* Statement used to read %_segdir entry */
- int nByte; /* Bytes allocated at pCsr->apSegment[] */
-
- /* Allocate space for the Fts3MultiSegReader.aCsr[] array */
- memset(pCsr, 0, sizeof(*pCsr));
- nByte = sizeof(Fts3SegReader *) * nSeg;
- pCsr->apSegment = (Fts3SegReader **)sqlite3_malloc(nByte);
-
- if( pCsr->apSegment==0 ){
- rc = SQLITE_NOMEM;
- }else{
- memset(pCsr->apSegment, 0, nByte);
- rc = fts3SqlStmt(p, SQL_SELECT_LEVEL, &pStmt, 0);
- }
- if( rc==SQLITE_OK ){
- int i;
- int rc2;
- sqlite3_bind_int64(pStmt, 1, iAbsLevel);
- assert( pCsr->nSegment==0 );
- for(i=0; rc==SQLITE_OK && sqlite3_step(pStmt)==SQLITE_ROW && i<nSeg; i++){
- rc = sqlite3Fts3SegReaderNew(i, 0,
- sqlite3_column_int64(pStmt, 1), /* segdir.start_block */
- sqlite3_column_int64(pStmt, 2), /* segdir.leaves_end_block */
- sqlite3_column_int64(pStmt, 3), /* segdir.end_block */
- sqlite3_column_blob(pStmt, 4), /* segdir.root */
- sqlite3_column_bytes(pStmt, 4), /* segdir.root */
- &pCsr->apSegment[i]
- );
- pCsr->nSegment++;
- }
- rc2 = sqlite3_reset(pStmt);
- if( rc==SQLITE_OK ) rc = rc2;
- }
-
- return rc;
-}
-
-typedef struct IncrmergeWriter IncrmergeWriter;
-typedef struct NodeWriter NodeWriter;
-typedef struct Blob Blob;
-typedef struct NodeReader NodeReader;
-
-/*
-** An instance of the following structure is used as a dynamic buffer
-** to build up nodes or other blobs of data in.
-**
-** The function blobGrowBuffer() is used to extend the allocation.
-*/
-struct Blob {
- char *a; /* Pointer to allocation */
- int n; /* Number of valid bytes of data in a[] */
- int nAlloc; /* Allocated size of a[] (nAlloc>=n) */
-};
-
-/*
-** This structure is used to build up buffers containing segment b-tree
-** nodes (blocks).
-*/
-struct NodeWriter {
- sqlite3_int64 iBlock; /* Current block id */
- Blob key; /* Last key written to the current block */
- Blob block; /* Current block image */
-};
-
-/*
-** An object of this type contains the state required to create or append
-** to an appendable b-tree segment.
-*/
-struct IncrmergeWriter {
- int nLeafEst; /* Space allocated for leaf blocks */
- int nWork; /* Number of leaf pages flushed */
- sqlite3_int64 iAbsLevel; /* Absolute level of input segments */
- int iIdx; /* Index of *output* segment in iAbsLevel+1 */
- sqlite3_int64 iStart; /* Block number of first allocated block */
- sqlite3_int64 iEnd; /* Block number of last allocated block */
- sqlite3_int64 nLeafData; /* Bytes of leaf page data so far */
- u8 bNoLeafData; /* If true, store 0 for segment size */
- NodeWriter aNodeWriter[FTS_MAX_APPENDABLE_HEIGHT];
-};
-
-/*
-** An object of the following type is used to read data from a single
-** FTS segment node. See the following functions:
-**
-** nodeReaderInit()
-** nodeReaderNext()
-** nodeReaderRelease()
-*/
-struct NodeReader {
- const char *aNode;
- int nNode;
- int iOff; /* Current offset within aNode[] */
-
- /* Output variables. Containing the current node entry. */
- sqlite3_int64 iChild; /* Pointer to child node */
- Blob term; /* Current term */
- const char *aDoclist; /* Pointer to doclist */
- int nDoclist; /* Size of doclist in bytes */
-};
-
-/*
-** If *pRc is not SQLITE_OK when this function is called, it is a no-op.
-** Otherwise, if the allocation at pBlob->a is not already at least nMin
-** bytes in size, extend (realloc) it to be so.
-**
-** If an OOM error occurs, set *pRc to SQLITE_NOMEM and leave pBlob->a
-** unmodified. Otherwise, if the allocation succeeds, update pBlob->nAlloc
-** to reflect the new size of the pBlob->a[] buffer.
-*/
-static void blobGrowBuffer(Blob *pBlob, int nMin, int *pRc){
- if( *pRc==SQLITE_OK && nMin>pBlob->nAlloc ){
- int nAlloc = nMin;
- char *a = (char *)sqlite3_realloc(pBlob->a, nAlloc);
- if( a ){
- pBlob->nAlloc = nAlloc;
- pBlob->a = a;
- }else{
- *pRc = SQLITE_NOMEM;
- }
- }
-}
-
-/*
-** Attempt to advance the node-reader object passed as the first argument to
-** the next entry on the node.
-**
-** Return an error code if an error occurs (SQLITE_NOMEM is possible).
-** Otherwise return SQLITE_OK. If there is no next entry on the node
-** (e.g. because the current entry is the last) set NodeReader->aNode to
-** NULL to indicate EOF. Otherwise, populate the NodeReader structure output
-** variables for the new entry.
-*/
-static int nodeReaderNext(NodeReader *p){
- int bFirst = (p->term.n==0); /* True for first term on the node */
- int nPrefix = 0; /* Bytes to copy from previous term */
- int nSuffix = 0; /* Bytes to append to the prefix */
- int rc = SQLITE_OK; /* Return code */
-
- assert( p->aNode );
- if( p->iChild && bFirst==0 ) p->iChild++;
- if( p->iOff>=p->nNode ){
- /* EOF */
- p->aNode = 0;
- }else{
- if( bFirst==0 ){
- p->iOff += fts3GetVarint32(&p->aNode[p->iOff], &nPrefix);
- }
- p->iOff += fts3GetVarint32(&p->aNode[p->iOff], &nSuffix);
-
- blobGrowBuffer(&p->term, nPrefix+nSuffix, &rc);
- if( rc==SQLITE_OK ){
- memcpy(&p->term.a[nPrefix], &p->aNode[p->iOff], nSuffix);
- p->term.n = nPrefix+nSuffix;
- p->iOff += nSuffix;
- if( p->iChild==0 ){
- p->iOff += fts3GetVarint32(&p->aNode[p->iOff], &p->nDoclist);
- p->aDoclist = &p->aNode[p->iOff];
- p->iOff += p->nDoclist;
- }
- }
- }
-
- assert( p->iOff<=p->nNode );
-
- return rc;
-}
-
-/*
-** Release all dynamic resources held by node-reader object *p.
-*/
-static void nodeReaderRelease(NodeReader *p){
- sqlite3_free(p->term.a);
-}
-
-/*
-** Initialize a node-reader object to read the node in buffer aNode/nNode.
-**
-** If successful, SQLITE_OK is returned and the NodeReader object set to
-** point to the first entry on the node (if any). Otherwise, an SQLite
-** error code is returned.
-*/
-static int nodeReaderInit(NodeReader *p, const char *aNode, int nNode){
- memset(p, 0, sizeof(NodeReader));
- p->aNode = aNode;
- p->nNode = nNode;
-
- /* Figure out if this is a leaf or an internal node. */
- if( p->aNode[0] ){
- /* An internal node. */
- p->iOff = 1 + sqlite3Fts3GetVarint(&p->aNode[1], &p->iChild);
- }else{
- p->iOff = 1;
- }
-
- return nodeReaderNext(p);
-}
-
-/*
-** This function is called while writing an FTS segment each time a leaf o
-** node is finished and written to disk. The key (zTerm/nTerm) is guaranteed
-** to be greater than the largest key on the node just written, but smaller
-** than or equal to the first key that will be written to the next leaf
-** node.
-**
-** The block id of the leaf node just written to disk may be found in
-** (pWriter->aNodeWriter[0].iBlock) when this function is called.
-*/
-static int fts3IncrmergePush(
- Fts3Table *p, /* Fts3 table handle */
- IncrmergeWriter *pWriter, /* Writer object */
- const char *zTerm, /* Term to write to internal node */
- int nTerm /* Bytes at zTerm */
-){
- sqlite3_int64 iPtr = pWriter->aNodeWriter[0].iBlock;
- int iLayer;
-
- assert( nTerm>0 );
- for(iLayer=1; ALWAYS(iLayer<FTS_MAX_APPENDABLE_HEIGHT); iLayer++){
- sqlite3_int64 iNextPtr = 0;
- NodeWriter *pNode = &pWriter->aNodeWriter[iLayer];
- int rc = SQLITE_OK;
- int nPrefix;
- int nSuffix;
- int nSpace;
-
- /* Figure out how much space the key will consume if it is written to
- ** the current node of layer iLayer. Due to the prefix compression,
- ** the space required changes depending on which node the key is to
- ** be added to. */
- nPrefix = fts3PrefixCompress(pNode->key.a, pNode->key.n, zTerm, nTerm);
- nSuffix = nTerm - nPrefix;
- nSpace = sqlite3Fts3VarintLen(nPrefix);
- nSpace += sqlite3Fts3VarintLen(nSuffix) + nSuffix;
-
- if( pNode->key.n==0 || (pNode->block.n + nSpace)<=p->nNodeSize ){
- /* If the current node of layer iLayer contains zero keys, or if adding
- ** the key to it will not cause it to grow to larger than nNodeSize
- ** bytes in size, write the key here. */
-
- Blob *pBlk = &pNode->block;
- if( pBlk->n==0 ){
- blobGrowBuffer(pBlk, p->nNodeSize, &rc);
- if( rc==SQLITE_OK ){
- pBlk->a[0] = (char)iLayer;
- pBlk->n = 1 + sqlite3Fts3PutVarint(&pBlk->a[1], iPtr);
- }
- }
- blobGrowBuffer(pBlk, pBlk->n + nSpace, &rc);
- blobGrowBuffer(&pNode->key, nTerm, &rc);
-
- if( rc==SQLITE_OK ){
- if( pNode->key.n ){
- pBlk->n += sqlite3Fts3PutVarint(&pBlk->a[pBlk->n], nPrefix);
- }
- pBlk->n += sqlite3Fts3PutVarint(&pBlk->a[pBlk->n], nSuffix);
- memcpy(&pBlk->a[pBlk->n], &zTerm[nPrefix], nSuffix);
- pBlk->n += nSuffix;
-
- memcpy(pNode->key.a, zTerm, nTerm);
- pNode->key.n = nTerm;
- }
- }else{
- /* Otherwise, flush the current node of layer iLayer to disk.
- ** Then allocate a new, empty sibling node. The key will be written
- ** into the parent of this node. */
- rc = fts3WriteSegment(p, pNode->iBlock, pNode->block.a, pNode->block.n);
-
- assert( pNode->block.nAlloc>=p->nNodeSize );
- pNode->block.a[0] = (char)iLayer;
- pNode->block.n = 1 + sqlite3Fts3PutVarint(&pNode->block.a[1], iPtr+1);
-
- iNextPtr = pNode->iBlock;
- pNode->iBlock++;
- pNode->key.n = 0;
- }
-
- if( rc!=SQLITE_OK || iNextPtr==0 ) return rc;
- iPtr = iNextPtr;
- }
-
- assert( 0 );
- return 0;
-}
-
-/*
-** Append a term and (optionally) doclist to the FTS segment node currently
-** stored in blob *pNode. The node need not contain any terms, but the
-** header must be written before this function is called.
-**
-** A node header is a single 0x00 byte for a leaf node, or a height varint
-** followed by the left-hand-child varint for an internal node.
-**
-** The term to be appended is passed via arguments zTerm/nTerm. For a
-** leaf node, the doclist is passed as aDoclist/nDoclist. For an internal
-** node, both aDoclist and nDoclist must be passed 0.
-**
-** If the size of the value in blob pPrev is zero, then this is the first
-** term written to the node. Otherwise, pPrev contains a copy of the
-** previous term. Before this function returns, it is updated to contain a
-** copy of zTerm/nTerm.
-**
-** It is assumed that the buffer associated with pNode is already large
-** enough to accommodate the new entry. The buffer associated with pPrev
-** is extended by this function if requrired.
-**
-** If an error (i.e. OOM condition) occurs, an SQLite error code is
-** returned. Otherwise, SQLITE_OK.
-*/
-static int fts3AppendToNode(
- Blob *pNode, /* Current node image to append to */
- Blob *pPrev, /* Buffer containing previous term written */
- const char *zTerm, /* New term to write */
- int nTerm, /* Size of zTerm in bytes */
- const char *aDoclist, /* Doclist (or NULL) to write */
- int nDoclist /* Size of aDoclist in bytes */
-){
- int rc = SQLITE_OK; /* Return code */
- int bFirst = (pPrev->n==0); /* True if this is the first term written */
- int nPrefix; /* Size of term prefix in bytes */
- int nSuffix; /* Size of term suffix in bytes */
-
- /* Node must have already been started. There must be a doclist for a
- ** leaf node, and there must not be a doclist for an internal node. */
- assert( pNode->n>0 );
- assert( (pNode->a[0]=='\0')==(aDoclist!=0) );
-
- blobGrowBuffer(pPrev, nTerm, &rc);
- if( rc!=SQLITE_OK ) return rc;
-
- nPrefix = fts3PrefixCompress(pPrev->a, pPrev->n, zTerm, nTerm);
- nSuffix = nTerm - nPrefix;
- memcpy(pPrev->a, zTerm, nTerm);
- pPrev->n = nTerm;
-
- if( bFirst==0 ){
- pNode->n += sqlite3Fts3PutVarint(&pNode->a[pNode->n], nPrefix);
- }
- pNode->n += sqlite3Fts3PutVarint(&pNode->a[pNode->n], nSuffix);
- memcpy(&pNode->a[pNode->n], &zTerm[nPrefix], nSuffix);
- pNode->n += nSuffix;
-
- if( aDoclist ){
- pNode->n += sqlite3Fts3PutVarint(&pNode->a[pNode->n], nDoclist);
- memcpy(&pNode->a[pNode->n], aDoclist, nDoclist);
- pNode->n += nDoclist;
- }
-
- assert( pNode->n<=pNode->nAlloc );
-
- return SQLITE_OK;
-}
-
-/*
-** Append the current term and doclist pointed to by cursor pCsr to the
-** appendable b-tree segment opened for writing by pWriter.
-**
-** Return SQLITE_OK if successful, or an SQLite error code otherwise.
-*/
-static int fts3IncrmergeAppend(
- Fts3Table *p, /* Fts3 table handle */
- IncrmergeWriter *pWriter, /* Writer object */
- Fts3MultiSegReader *pCsr /* Cursor containing term and doclist */
-){
- const char *zTerm = pCsr->zTerm;
- int nTerm = pCsr->nTerm;
- const char *aDoclist = pCsr->aDoclist;
- int nDoclist = pCsr->nDoclist;
- int rc = SQLITE_OK; /* Return code */
- int nSpace; /* Total space in bytes required on leaf */
- int nPrefix; /* Size of prefix shared with previous term */
- int nSuffix; /* Size of suffix (nTerm - nPrefix) */
- NodeWriter *pLeaf; /* Object used to write leaf nodes */
-
- pLeaf = &pWriter->aNodeWriter[0];
- nPrefix = fts3PrefixCompress(pLeaf->key.a, pLeaf->key.n, zTerm, nTerm);
- nSuffix = nTerm - nPrefix;
-
- nSpace = sqlite3Fts3VarintLen(nPrefix);
- nSpace += sqlite3Fts3VarintLen(nSuffix) + nSuffix;
- nSpace += sqlite3Fts3VarintLen(nDoclist) + nDoclist;
-
- /* If the current block is not empty, and if adding this term/doclist
- ** to the current block would make it larger than Fts3Table.nNodeSize
- ** bytes, write this block out to the database. */
- if( pLeaf->block.n>0 && (pLeaf->block.n + nSpace)>p->nNodeSize ){
- rc = fts3WriteSegment(p, pLeaf->iBlock, pLeaf->block.a, pLeaf->block.n);
- pWriter->nWork++;
-
- /* Add the current term to the parent node. The term added to the
- ** parent must:
- **
- ** a) be greater than the largest term on the leaf node just written
- ** to the database (still available in pLeaf->key), and
- **
- ** b) be less than or equal to the term about to be added to the new
- ** leaf node (zTerm/nTerm).
- **
- ** In other words, it must be the prefix of zTerm 1 byte longer than
- ** the common prefix (if any) of zTerm and pWriter->zTerm.
- */
- if( rc==SQLITE_OK ){
- rc = fts3IncrmergePush(p, pWriter, zTerm, nPrefix+1);
- }
-
- /* Advance to the next output block */
- pLeaf->iBlock++;
- pLeaf->key.n = 0;
- pLeaf->block.n = 0;
-
- nSuffix = nTerm;
- nSpace = 1;
- nSpace += sqlite3Fts3VarintLen(nSuffix) + nSuffix;
- nSpace += sqlite3Fts3VarintLen(nDoclist) + nDoclist;
- }
-
- pWriter->nLeafData += nSpace;
- blobGrowBuffer(&pLeaf->block, pLeaf->block.n + nSpace, &rc);
- if( rc==SQLITE_OK ){
- if( pLeaf->block.n==0 ){
- pLeaf->block.n = 1;
- pLeaf->block.a[0] = '\0';
- }
- rc = fts3AppendToNode(
- &pLeaf->block, &pLeaf->key, zTerm, nTerm, aDoclist, nDoclist
- );
- }
-
- return rc;
-}
-
-/*
-** This function is called to release all dynamic resources held by the
-** merge-writer object pWriter, and if no error has occurred, to flush
-** all outstanding node buffers held by pWriter to disk.
-**
-** If *pRc is not SQLITE_OK when this function is called, then no attempt
-** is made to write any data to disk. Instead, this function serves only
-** to release outstanding resources.
-**
-** Otherwise, if *pRc is initially SQLITE_OK and an error occurs while
-** flushing buffers to disk, *pRc is set to an SQLite error code before
-** returning.
-*/
-static void fts3IncrmergeRelease(
- Fts3Table *p, /* FTS3 table handle */
- IncrmergeWriter *pWriter, /* Merge-writer object */
- int *pRc /* IN/OUT: Error code */
-){
- int i; /* Used to iterate through non-root layers */
- int iRoot; /* Index of root in pWriter->aNodeWriter */
- NodeWriter *pRoot; /* NodeWriter for root node */
- int rc = *pRc; /* Error code */
-
- /* Set iRoot to the index in pWriter->aNodeWriter[] of the output segment
- ** root node. If the segment fits entirely on a single leaf node, iRoot
- ** will be set to 0. If the root node is the parent of the leaves, iRoot
- ** will be 1. And so on. */
- for(iRoot=FTS_MAX_APPENDABLE_HEIGHT-1; iRoot>=0; iRoot--){
- NodeWriter *pNode = &pWriter->aNodeWriter[iRoot];
- if( pNode->block.n>0 ) break;
- assert( *pRc || pNode->block.nAlloc==0 );
- assert( *pRc || pNode->key.nAlloc==0 );
- sqlite3_free(pNode->block.a);
- sqlite3_free(pNode->key.a);
- }
-
- /* Empty output segment. This is a no-op. */
- if( iRoot<0 ) return;
-
- /* The entire output segment fits on a single node. Normally, this means
- ** the node would be stored as a blob in the "root" column of the %_segdir
- ** table. However, this is not permitted in this case. The problem is that
- ** space has already been reserved in the %_segments table, and so the
- ** start_block and end_block fields of the %_segdir table must be populated.
- ** And, by design or by accident, released versions of FTS cannot handle
- ** segments that fit entirely on the root node with start_block!=0.
- **
- ** Instead, create a synthetic root node that contains nothing but a
- ** pointer to the single content node. So that the segment consists of a
- ** single leaf and a single interior (root) node.
- **
- ** Todo: Better might be to defer allocating space in the %_segments
- ** table until we are sure it is needed.
- */
- if( iRoot==0 ){
- Blob *pBlock = &pWriter->aNodeWriter[1].block;
- blobGrowBuffer(pBlock, 1 + FTS3_VARINT_MAX, &rc);
- if( rc==SQLITE_OK ){
- pBlock->a[0] = 0x01;
- pBlock->n = 1 + sqlite3Fts3PutVarint(
- &pBlock->a[1], pWriter->aNodeWriter[0].iBlock
- );
- }
- iRoot = 1;
- }
- pRoot = &pWriter->aNodeWriter[iRoot];
-
- /* Flush all currently outstanding nodes to disk. */
- for(i=0; i<iRoot; i++){
- NodeWriter *pNode = &pWriter->aNodeWriter[i];
- if( pNode->block.n>0 && rc==SQLITE_OK ){
- rc = fts3WriteSegment(p, pNode->iBlock, pNode->block.a, pNode->block.n);
- }
- sqlite3_free(pNode->block.a);
- sqlite3_free(pNode->key.a);
- }
-
- /* Write the %_segdir record. */
- if( rc==SQLITE_OK ){
- rc = fts3WriteSegdir(p,
- pWriter->iAbsLevel+1, /* level */
- pWriter->iIdx, /* idx */
- pWriter->iStart, /* start_block */
- pWriter->aNodeWriter[0].iBlock, /* leaves_end_block */
- pWriter->iEnd, /* end_block */
- (pWriter->bNoLeafData==0 ? pWriter->nLeafData : 0), /* end_block */
- pRoot->block.a, pRoot->block.n /* root */
- );
- }
- sqlite3_free(pRoot->block.a);
- sqlite3_free(pRoot->key.a);
-
- *pRc = rc;
-}
-
-/*
-** Compare the term in buffer zLhs (size in bytes nLhs) with that in
-** zRhs (size in bytes nRhs) using memcmp. If one term is a prefix of
-** the other, it is considered to be smaller than the other.
-**
-** Return -ve if zLhs is smaller than zRhs, 0 if it is equal, or +ve
-** if it is greater.
-*/
-static int fts3TermCmp(
- const char *zLhs, int nLhs, /* LHS of comparison */
- const char *zRhs, int nRhs /* RHS of comparison */
-){
- int nCmp = MIN(nLhs, nRhs);
- int res;
-
- res = memcmp(zLhs, zRhs, nCmp);
- if( res==0 ) res = nLhs - nRhs;
-
- return res;
-}
-
-
-/*
-** Query to see if the entry in the %_segments table with blockid iEnd is
-** NULL. If no error occurs and the entry is NULL, set *pbRes 1 before
-** returning. Otherwise, set *pbRes to 0.
-**
-** Or, if an error occurs while querying the database, return an SQLite
-** error code. The final value of *pbRes is undefined in this case.
-**
-** This is used to test if a segment is an "appendable" segment. If it
-** is, then a NULL entry has been inserted into the %_segments table
-** with blockid %_segdir.end_block.
-*/
-static int fts3IsAppendable(Fts3Table *p, sqlite3_int64 iEnd, int *pbRes){
- int bRes = 0; /* Result to set *pbRes to */
- sqlite3_stmt *pCheck = 0; /* Statement to query database with */
- int rc; /* Return code */
-
- rc = fts3SqlStmt(p, SQL_SEGMENT_IS_APPENDABLE, &pCheck, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pCheck, 1, iEnd);
- if( SQLITE_ROW==sqlite3_step(pCheck) ) bRes = 1;
- rc = sqlite3_reset(pCheck);
- }
-
- *pbRes = bRes;
- return rc;
-}
-
-/*
-** This function is called when initializing an incremental-merge operation.
-** It checks if the existing segment with index value iIdx at absolute level
-** (iAbsLevel+1) can be appended to by the incremental merge. If it can, the
-** merge-writer object *pWriter is initialized to write to it.
-**
-** An existing segment can be appended to by an incremental merge if:
-**
-** * It was initially created as an appendable segment (with all required
-** space pre-allocated), and
-**
-** * The first key read from the input (arguments zKey and nKey) is
-** greater than the largest key currently stored in the potential
-** output segment.
-*/
-static int fts3IncrmergeLoad(
- Fts3Table *p, /* Fts3 table handle */
- sqlite3_int64 iAbsLevel, /* Absolute level of input segments */
- int iIdx, /* Index of candidate output segment */
- const char *zKey, /* First key to write */
- int nKey, /* Number of bytes in nKey */
- IncrmergeWriter *pWriter /* Populate this object */
-){
- int rc; /* Return code */
- sqlite3_stmt *pSelect = 0; /* SELECT to read %_segdir entry */
-
- rc = fts3SqlStmt(p, SQL_SELECT_SEGDIR, &pSelect, 0);
- if( rc==SQLITE_OK ){
- sqlite3_int64 iStart = 0; /* Value of %_segdir.start_block */
- sqlite3_int64 iLeafEnd = 0; /* Value of %_segdir.leaves_end_block */
- sqlite3_int64 iEnd = 0; /* Value of %_segdir.end_block */
- const char *aRoot = 0; /* Pointer to %_segdir.root buffer */
- int nRoot = 0; /* Size of aRoot[] in bytes */
- int rc2; /* Return code from sqlite3_reset() */
- int bAppendable = 0; /* Set to true if segment is appendable */
-
- /* Read the %_segdir entry for index iIdx absolute level (iAbsLevel+1) */
- sqlite3_bind_int64(pSelect, 1, iAbsLevel+1);
- sqlite3_bind_int(pSelect, 2, iIdx);
- if( sqlite3_step(pSelect)==SQLITE_ROW ){
- iStart = sqlite3_column_int64(pSelect, 1);
- iLeafEnd = sqlite3_column_int64(pSelect, 2);
- fts3ReadEndBlockField(pSelect, 3, &iEnd, &pWriter->nLeafData);
- if( pWriter->nLeafData<0 ){
- pWriter->nLeafData = pWriter->nLeafData * -1;
- }
- pWriter->bNoLeafData = (pWriter->nLeafData==0);
- nRoot = sqlite3_column_bytes(pSelect, 4);
- aRoot = sqlite3_column_blob(pSelect, 4);
- }else{
- return sqlite3_reset(pSelect);
- }
-
- /* Check for the zero-length marker in the %_segments table */
- rc = fts3IsAppendable(p, iEnd, &bAppendable);
-
- /* Check that zKey/nKey is larger than the largest key the candidate */
- if( rc==SQLITE_OK && bAppendable ){
- char *aLeaf = 0;
- int nLeaf = 0;
-
- rc = sqlite3Fts3ReadBlock(p, iLeafEnd, &aLeaf, &nLeaf, 0);
- if( rc==SQLITE_OK ){
- NodeReader reader;
- for(rc = nodeReaderInit(&reader, aLeaf, nLeaf);
- rc==SQLITE_OK && reader.aNode;
- rc = nodeReaderNext(&reader)
- ){
- assert( reader.aNode );
- }
- if( fts3TermCmp(zKey, nKey, reader.term.a, reader.term.n)<=0 ){
- bAppendable = 0;
- }
- nodeReaderRelease(&reader);
- }
- sqlite3_free(aLeaf);
- }
-
- if( rc==SQLITE_OK && bAppendable ){
- /* It is possible to append to this segment. Set up the IncrmergeWriter
- ** object to do so. */
- int i;
- int nHeight = (int)aRoot[0];
- NodeWriter *pNode;
-
- pWriter->nLeafEst = (int)((iEnd - iStart) + 1)/FTS_MAX_APPENDABLE_HEIGHT;
- pWriter->iStart = iStart;
- pWriter->iEnd = iEnd;
- pWriter->iAbsLevel = iAbsLevel;
- pWriter->iIdx = iIdx;
-
- for(i=nHeight+1; i<FTS_MAX_APPENDABLE_HEIGHT; i++){
- pWriter->aNodeWriter[i].iBlock = pWriter->iStart + i*pWriter->nLeafEst;
- }
-
- pNode = &pWriter->aNodeWriter[nHeight];
- pNode->iBlock = pWriter->iStart + pWriter->nLeafEst*nHeight;
- blobGrowBuffer(&pNode->block, MAX(nRoot, p->nNodeSize), &rc);
- if( rc==SQLITE_OK ){
- memcpy(pNode->block.a, aRoot, nRoot);
- pNode->block.n = nRoot;
- }
-
- for(i=nHeight; i>=0 && rc==SQLITE_OK; i--){
- NodeReader reader;
- pNode = &pWriter->aNodeWriter[i];
-
- rc = nodeReaderInit(&reader, pNode->block.a, pNode->block.n);
- while( reader.aNode && rc==SQLITE_OK ) rc = nodeReaderNext(&reader);
- blobGrowBuffer(&pNode->key, reader.term.n, &rc);
- if( rc==SQLITE_OK ){
- memcpy(pNode->key.a, reader.term.a, reader.term.n);
- pNode->key.n = reader.term.n;
- if( i>0 ){
- char *aBlock = 0;
- int nBlock = 0;
- pNode = &pWriter->aNodeWriter[i-1];
- pNode->iBlock = reader.iChild;
- rc = sqlite3Fts3ReadBlock(p, reader.iChild, &aBlock, &nBlock, 0);
- blobGrowBuffer(&pNode->block, MAX(nBlock, p->nNodeSize), &rc);
- if( rc==SQLITE_OK ){
- memcpy(pNode->block.a, aBlock, nBlock);
- pNode->block.n = nBlock;
- }
- sqlite3_free(aBlock);
- }
- }
- nodeReaderRelease(&reader);
- }
- }
-
- rc2 = sqlite3_reset(pSelect);
- if( rc==SQLITE_OK ) rc = rc2;
- }
-
- return rc;
-}
-
-/*
-** Determine the largest segment index value that exists within absolute
-** level iAbsLevel+1. If no error occurs, set *piIdx to this value plus
-** one before returning SQLITE_OK. Or, if there are no segments at all
-** within level iAbsLevel, set *piIdx to zero.
-**
-** If an error occurs, return an SQLite error code. The final value of
-** *piIdx is undefined in this case.
-*/
-static int fts3IncrmergeOutputIdx(
- Fts3Table *p, /* FTS Table handle */
- sqlite3_int64 iAbsLevel, /* Absolute index of input segments */
- int *piIdx /* OUT: Next free index at iAbsLevel+1 */
-){
- int rc;
- sqlite3_stmt *pOutputIdx = 0; /* SQL used to find output index */
-
- rc = fts3SqlStmt(p, SQL_NEXT_SEGMENT_INDEX, &pOutputIdx, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pOutputIdx, 1, iAbsLevel+1);
- sqlite3_step(pOutputIdx);
- *piIdx = sqlite3_column_int(pOutputIdx, 0);
- rc = sqlite3_reset(pOutputIdx);
- }
-
- return rc;
-}
-
-/*
-** Allocate an appendable output segment on absolute level iAbsLevel+1
-** with idx value iIdx.
-**
-** In the %_segdir table, a segment is defined by the values in three
-** columns:
-**
-** start_block
-** leaves_end_block
-** end_block
-**
-** When an appendable segment is allocated, it is estimated that the
-** maximum number of leaf blocks that may be required is the sum of the
-** number of leaf blocks consumed by the input segments, plus the number
-** of input segments, multiplied by two. This value is stored in stack
-** variable nLeafEst.
-**
-** A total of 16*nLeafEst blocks are allocated when an appendable segment
-** is created ((1 + end_block - start_block)==16*nLeafEst). The contiguous
-** array of leaf nodes starts at the first block allocated. The array
-** of interior nodes that are parents of the leaf nodes start at block
-** (start_block + (1 + end_block - start_block) / 16). And so on.
-**
-** In the actual code below, the value "16" is replaced with the
-** pre-processor macro FTS_MAX_APPENDABLE_HEIGHT.
-*/
-static int fts3IncrmergeWriter(
- Fts3Table *p, /* Fts3 table handle */
- sqlite3_int64 iAbsLevel, /* Absolute level of input segments */
- int iIdx, /* Index of new output segment */
- Fts3MultiSegReader *pCsr, /* Cursor that data will be read from */
- IncrmergeWriter *pWriter /* Populate this object */
-){
- int rc; /* Return Code */
- int i; /* Iterator variable */
- int nLeafEst = 0; /* Blocks allocated for leaf nodes */
- sqlite3_stmt *pLeafEst = 0; /* SQL used to determine nLeafEst */
- sqlite3_stmt *pFirstBlock = 0; /* SQL used to determine first block */
-
- /* Calculate nLeafEst. */
- rc = fts3SqlStmt(p, SQL_MAX_LEAF_NODE_ESTIMATE, &pLeafEst, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pLeafEst, 1, iAbsLevel);
- sqlite3_bind_int64(pLeafEst, 2, pCsr->nSegment);
- if( SQLITE_ROW==sqlite3_step(pLeafEst) ){
- nLeafEst = sqlite3_column_int(pLeafEst, 0);
- }
- rc = sqlite3_reset(pLeafEst);
- }
- if( rc!=SQLITE_OK ) return rc;
-
- /* Calculate the first block to use in the output segment */
- rc = fts3SqlStmt(p, SQL_NEXT_SEGMENTS_ID, &pFirstBlock, 0);
- if( rc==SQLITE_OK ){
- if( SQLITE_ROW==sqlite3_step(pFirstBlock) ){
- pWriter->iStart = sqlite3_column_int64(pFirstBlock, 0);
- pWriter->iEnd = pWriter->iStart - 1;
- pWriter->iEnd += nLeafEst * FTS_MAX_APPENDABLE_HEIGHT;
- }
- rc = sqlite3_reset(pFirstBlock);
- }
- if( rc!=SQLITE_OK ) return rc;
-
- /* Insert the marker in the %_segments table to make sure nobody tries
- ** to steal the space just allocated. This is also used to identify
- ** appendable segments. */
- rc = fts3WriteSegment(p, pWriter->iEnd, 0, 0);
- if( rc!=SQLITE_OK ) return rc;
-
- pWriter->iAbsLevel = iAbsLevel;
- pWriter->nLeafEst = nLeafEst;
- pWriter->iIdx = iIdx;
-
- /* Set up the array of NodeWriter objects */
- for(i=0; i<FTS_MAX_APPENDABLE_HEIGHT; i++){
- pWriter->aNodeWriter[i].iBlock = pWriter->iStart + i*pWriter->nLeafEst;
- }
- return SQLITE_OK;
-}
-
-/*
-** Remove an entry from the %_segdir table. This involves running the
-** following two statements:
-**
-** DELETE FROM %_segdir WHERE level = :iAbsLevel AND idx = :iIdx
-** UPDATE %_segdir SET idx = idx - 1 WHERE level = :iAbsLevel AND idx > :iIdx
-**
-** The DELETE statement removes the specific %_segdir level. The UPDATE
-** statement ensures that the remaining segments have contiguously allocated
-** idx values.
-*/
-static int fts3RemoveSegdirEntry(
- Fts3Table *p, /* FTS3 table handle */
- sqlite3_int64 iAbsLevel, /* Absolute level to delete from */
- int iIdx /* Index of %_segdir entry to delete */
-){
- int rc; /* Return code */
- sqlite3_stmt *pDelete = 0; /* DELETE statement */
-
- rc = fts3SqlStmt(p, SQL_DELETE_SEGDIR_ENTRY, &pDelete, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pDelete, 1, iAbsLevel);
- sqlite3_bind_int(pDelete, 2, iIdx);
- sqlite3_step(pDelete);
- rc = sqlite3_reset(pDelete);
- }
-
- return rc;
-}
-
-/*
-** One or more segments have just been removed from absolute level iAbsLevel.
-** Update the 'idx' values of the remaining segments in the level so that
-** the idx values are a contiguous sequence starting from 0.
-*/
-static int fts3RepackSegdirLevel(
- Fts3Table *p, /* FTS3 table handle */
- sqlite3_int64 iAbsLevel /* Absolute level to repack */
-){
- int rc; /* Return code */
- int *aIdx = 0; /* Array of remaining idx values */
- int nIdx = 0; /* Valid entries in aIdx[] */
- int nAlloc = 0; /* Allocated size of aIdx[] */
- int i; /* Iterator variable */
- sqlite3_stmt *pSelect = 0; /* Select statement to read idx values */
- sqlite3_stmt *pUpdate = 0; /* Update statement to modify idx values */
-
- rc = fts3SqlStmt(p, SQL_SELECT_INDEXES, &pSelect, 0);
- if( rc==SQLITE_OK ){
- int rc2;
- sqlite3_bind_int64(pSelect, 1, iAbsLevel);
- while( SQLITE_ROW==sqlite3_step(pSelect) ){
- if( nIdx>=nAlloc ){
- int *aNew;
- nAlloc += 16;
- aNew = sqlite3_realloc(aIdx, nAlloc*sizeof(int));
- if( !aNew ){
- rc = SQLITE_NOMEM;
- break;
- }
- aIdx = aNew;
- }
- aIdx[nIdx++] = sqlite3_column_int(pSelect, 0);
- }
- rc2 = sqlite3_reset(pSelect);
- if( rc==SQLITE_OK ) rc = rc2;
- }
-
- if( rc==SQLITE_OK ){
- rc = fts3SqlStmt(p, SQL_SHIFT_SEGDIR_ENTRY, &pUpdate, 0);
- }
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pUpdate, 2, iAbsLevel);
- }
-
- assert( p->bIgnoreSavepoint==0 );
- p->bIgnoreSavepoint = 1;
- for(i=0; rc==SQLITE_OK && i<nIdx; i++){
- if( aIdx[i]!=i ){
- sqlite3_bind_int(pUpdate, 3, aIdx[i]);
- sqlite3_bind_int(pUpdate, 1, i);
- sqlite3_step(pUpdate);
- rc = sqlite3_reset(pUpdate);
- }
- }
- p->bIgnoreSavepoint = 0;
-
- sqlite3_free(aIdx);
- return rc;
-}
-
-static void fts3StartNode(Blob *pNode, int iHeight, sqlite3_int64 iChild){
- pNode->a[0] = (char)iHeight;
- if( iChild ){
- assert( pNode->nAlloc>=1+sqlite3Fts3VarintLen(iChild) );
- pNode->n = 1 + sqlite3Fts3PutVarint(&pNode->a[1], iChild);
- }else{
- assert( pNode->nAlloc>=1 );
- pNode->n = 1;
- }
-}
-
-/*
-** The first two arguments are a pointer to and the size of a segment b-tree
-** node. The node may be a leaf or an internal node.
-**
-** This function creates a new node image in blob object *pNew by copying
-** all terms that are greater than or equal to zTerm/nTerm (for leaf nodes)
-** or greater than zTerm/nTerm (for internal nodes) from aNode/nNode.
-*/
-static int fts3TruncateNode(
- const char *aNode, /* Current node image */
- int nNode, /* Size of aNode in bytes */
- Blob *pNew, /* OUT: Write new node image here */
- const char *zTerm, /* Omit all terms smaller than this */
- int nTerm, /* Size of zTerm in bytes */
- sqlite3_int64 *piBlock /* OUT: Block number in next layer down */
-){
- NodeReader reader; /* Reader object */
- Blob prev = {0, 0, 0}; /* Previous term written to new node */
- int rc = SQLITE_OK; /* Return code */
- int bLeaf = aNode[0]=='\0'; /* True for a leaf node */
-
- /* Allocate required output space */
- blobGrowBuffer(pNew, nNode, &rc);
- if( rc!=SQLITE_OK ) return rc;
- pNew->n = 0;
-
- /* Populate new node buffer */
- for(rc = nodeReaderInit(&reader, aNode, nNode);
- rc==SQLITE_OK && reader.aNode;
- rc = nodeReaderNext(&reader)
- ){
- if( pNew->n==0 ){
- int res = fts3TermCmp(reader.term.a, reader.term.n, zTerm, nTerm);
- if( res<0 || (bLeaf==0 && res==0) ) continue;
- fts3StartNode(pNew, (int)aNode[0], reader.iChild);
- *piBlock = reader.iChild;
- }
- rc = fts3AppendToNode(
- pNew, &prev, reader.term.a, reader.term.n,
- reader.aDoclist, reader.nDoclist
- );
- if( rc!=SQLITE_OK ) break;
- }
- if( pNew->n==0 ){
- fts3StartNode(pNew, (int)aNode[0], reader.iChild);
- *piBlock = reader.iChild;
- }
- assert( pNew->n<=pNew->nAlloc );
-
- nodeReaderRelease(&reader);
- sqlite3_free(prev.a);
- return rc;
-}
-
-/*
-** Remove all terms smaller than zTerm/nTerm from segment iIdx in absolute
-** level iAbsLevel. This may involve deleting entries from the %_segments
-** table, and modifying existing entries in both the %_segments and %_segdir
-** tables.
-**
-** SQLITE_OK is returned if the segment is updated successfully. Or an
-** SQLite error code otherwise.
-*/
-static int fts3TruncateSegment(
- Fts3Table *p, /* FTS3 table handle */
- sqlite3_int64 iAbsLevel, /* Absolute level of segment to modify */
- int iIdx, /* Index within level of segment to modify */
- const char *zTerm, /* Remove terms smaller than this */
- int nTerm /* Number of bytes in buffer zTerm */
-){
- int rc = SQLITE_OK; /* Return code */
- Blob root = {0,0,0}; /* New root page image */
- Blob block = {0,0,0}; /* Buffer used for any other block */
- sqlite3_int64 iBlock = 0; /* Block id */
- sqlite3_int64 iNewStart = 0; /* New value for iStartBlock */
- sqlite3_int64 iOldStart = 0; /* Old value for iStartBlock */
- sqlite3_stmt *pFetch = 0; /* Statement used to fetch segdir */
-
- rc = fts3SqlStmt(p, SQL_SELECT_SEGDIR, &pFetch, 0);
- if( rc==SQLITE_OK ){
- int rc2; /* sqlite3_reset() return code */
- sqlite3_bind_int64(pFetch, 1, iAbsLevel);
- sqlite3_bind_int(pFetch, 2, iIdx);
- if( SQLITE_ROW==sqlite3_step(pFetch) ){
- const char *aRoot = sqlite3_column_blob(pFetch, 4);
- int nRoot = sqlite3_column_bytes(pFetch, 4);
- iOldStart = sqlite3_column_int64(pFetch, 1);
- rc = fts3TruncateNode(aRoot, nRoot, &root, zTerm, nTerm, &iBlock);
- }
- rc2 = sqlite3_reset(pFetch);
- if( rc==SQLITE_OK ) rc = rc2;
- }
-
- while( rc==SQLITE_OK && iBlock ){
- char *aBlock = 0;
- int nBlock = 0;
- iNewStart = iBlock;
-
- rc = sqlite3Fts3ReadBlock(p, iBlock, &aBlock, &nBlock, 0);
- if( rc==SQLITE_OK ){
- rc = fts3TruncateNode(aBlock, nBlock, &block, zTerm, nTerm, &iBlock);
- }
- if( rc==SQLITE_OK ){
- rc = fts3WriteSegment(p, iNewStart, block.a, block.n);
- }
- sqlite3_free(aBlock);
- }
-
- /* Variable iNewStart now contains the first valid leaf node. */
- if( rc==SQLITE_OK && iNewStart ){
- sqlite3_stmt *pDel = 0;
- rc = fts3SqlStmt(p, SQL_DELETE_SEGMENTS_RANGE, &pDel, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pDel, 1, iOldStart);
- sqlite3_bind_int64(pDel, 2, iNewStart-1);
- sqlite3_step(pDel);
- rc = sqlite3_reset(pDel);
- }
- }
-
- if( rc==SQLITE_OK ){
- sqlite3_stmt *pChomp = 0;
- rc = fts3SqlStmt(p, SQL_CHOMP_SEGDIR, &pChomp, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int64(pChomp, 1, iNewStart);
- sqlite3_bind_blob(pChomp, 2, root.a, root.n, SQLITE_STATIC);
- sqlite3_bind_int64(pChomp, 3, iAbsLevel);
- sqlite3_bind_int(pChomp, 4, iIdx);
- sqlite3_step(pChomp);
- rc = sqlite3_reset(pChomp);
- }
- }
-
- sqlite3_free(root.a);
- sqlite3_free(block.a);
- return rc;
-}
-
-/*
-** This function is called after an incrmental-merge operation has run to
-** merge (or partially merge) two or more segments from absolute level
-** iAbsLevel.
-**
-** Each input segment is either removed from the db completely (if all of
-** its data was copied to the output segment by the incrmerge operation)
-** or modified in place so that it no longer contains those entries that
-** have been duplicated in the output segment.
-*/
-static int fts3IncrmergeChomp(
- Fts3Table *p, /* FTS table handle */
- sqlite3_int64 iAbsLevel, /* Absolute level containing segments */
- Fts3MultiSegReader *pCsr, /* Chomp all segments opened by this cursor */
- int *pnRem /* Number of segments not deleted */
-){
- int i;
- int nRem = 0;
- int rc = SQLITE_OK;
-
- for(i=pCsr->nSegment-1; i>=0 && rc==SQLITE_OK; i--){
- Fts3SegReader *pSeg = 0;
- int j;
-
- /* Find the Fts3SegReader object with Fts3SegReader.iIdx==i. It is hiding
- ** somewhere in the pCsr->apSegment[] array. */
- for(j=0; ALWAYS(j<pCsr->nSegment); j++){
- pSeg = pCsr->apSegment[j];
- if( pSeg->iIdx==i ) break;
- }
- assert( j<pCsr->nSegment && pSeg->iIdx==i );
-
- if( pSeg->aNode==0 ){
- /* Seg-reader is at EOF. Remove the entire input segment. */
- rc = fts3DeleteSegment(p, pSeg);
- if( rc==SQLITE_OK ){
- rc = fts3RemoveSegdirEntry(p, iAbsLevel, pSeg->iIdx);
- }
- *pnRem = 0;
- }else{
- /* The incremental merge did not copy all the data from this
- ** segment to the upper level. The segment is modified in place
- ** so that it contains no keys smaller than zTerm/nTerm. */
- const char *zTerm = pSeg->zTerm;
- int nTerm = pSeg->nTerm;
- rc = fts3TruncateSegment(p, iAbsLevel, pSeg->iIdx, zTerm, nTerm);
- nRem++;
- }
- }
-
- if( rc==SQLITE_OK && nRem!=pCsr->nSegment ){
- rc = fts3RepackSegdirLevel(p, iAbsLevel);
- }
-
- *pnRem = nRem;
- return rc;
-}
-
-/*
-** Store an incr-merge hint in the database.
-*/
-static int fts3IncrmergeHintStore(Fts3Table *p, Blob *pHint){
- sqlite3_stmt *pReplace = 0;
- int rc; /* Return code */
-
- rc = fts3SqlStmt(p, SQL_REPLACE_STAT, &pReplace, 0);
- if( rc==SQLITE_OK ){
- sqlite3_bind_int(pReplace, 1, FTS_STAT_INCRMERGEHINT);
- sqlite3_bind_blob(pReplace, 2, pHint->a, pHint->n, SQLITE_STATIC);
- sqlite3_step(pReplace);
- rc = sqlite3_reset(pReplace);
- }
-
- return rc;
-}
-
-/*
-** Load an incr-merge hint from the database. The incr-merge hint, if one
-** exists, is stored in the rowid==1 row of the %_stat table.
-**
-** If successful, populate blob *pHint with the value read from the %_stat
-** table and return SQLITE_OK. Otherwise, if an error occurs, return an
-** SQLite error code.
-*/
-static int fts3IncrmergeHintLoad(Fts3Table *p, Blob *pHint){
- sqlite3_stmt *pSelect = 0;
- int rc;
-
- pHint->n = 0;
- rc = fts3SqlStmt(p, SQL_SELECT_STAT, &pSelect, 0);
- if( rc==SQLITE_OK ){
- int rc2;
- sqlite3_bind_int(pSelect, 1, FTS_STAT_INCRMERGEHINT);
- if( SQLITE_ROW==sqlite3_step(pSelect) ){
- const char *aHint = sqlite3_column_blob(pSelect, 0);
- int nHint = sqlite3_column_bytes(pSelect, 0);
- if( aHint ){
- blobGrowBuffer(pHint, nHint, &rc);
- if( rc==SQLITE_OK ){
- memcpy(pHint->a, aHint, nHint);
- pHint->n = nHint;
- }
- }
- }
- rc2 = sqlite3_reset(pSelect);
- if( rc==SQLITE_OK ) rc = rc2;
- }
-
- return rc;
-}
-
-/*
-** If *pRc is not SQLITE_OK when this function is called, it is a no-op.
-** Otherwise, append an entry to the hint stored in blob *pHint. Each entry
-** consists of two varints, the absolute level number of the input segments
-** and the number of input segments.
-**
-** If successful, leave *pRc set to SQLITE_OK and return. If an error occurs,
-** set *pRc to an SQLite error code before returning.
-*/
-static void fts3IncrmergeHintPush(
- Blob *pHint, /* Hint blob to append to */
- i64 iAbsLevel, /* First varint to store in hint */
- int nInput, /* Second varint to store in hint */
- int *pRc /* IN/OUT: Error code */
-){
- blobGrowBuffer(pHint, pHint->n + 2*FTS3_VARINT_MAX, pRc);
- if( *pRc==SQLITE_OK ){
- pHint->n += sqlite3Fts3PutVarint(&pHint->a[pHint->n], iAbsLevel);
- pHint->n += sqlite3Fts3PutVarint(&pHint->a[pHint->n], (i64)nInput);
- }
-}
-
-/*
-** Read the last entry (most recently pushed) from the hint blob *pHint
-** and then remove the entry. Write the two values read to *piAbsLevel and
-** *pnInput before returning.
-**
-** If no error occurs, return SQLITE_OK. If the hint blob in *pHint does
-** not contain at least two valid varints, return SQLITE_CORRUPT_VTAB.
-*/
-static int fts3IncrmergeHintPop(Blob *pHint, i64 *piAbsLevel, int *pnInput){
- const int nHint = pHint->n;
- int i;
-
- i = pHint->n-2;
- while( i>0 && (pHint->a[i-1] & 0x80) ) i--;
- while( i>0 && (pHint->a[i-1] & 0x80) ) i--;
-
- pHint->n = i;
- i += sqlite3Fts3GetVarint(&pHint->a[i], piAbsLevel);
- i += fts3GetVarint32(&pHint->a[i], pnInput);
- if( i!=nHint ) return SQLITE_CORRUPT_VTAB;
-
- return SQLITE_OK;
-}
-
-
-/*
-** Attempt an incremental merge that writes nMerge leaf blocks.
-**
-** Incremental merges happen nMin segments at a time. The segments
-** to be merged are the nMin oldest segments (the ones with the smallest
-** values for the _segdir.idx field) in the highest level that contains
-** at least nMin segments. Multiple merges might occur in an attempt to
-** write the quota of nMerge leaf blocks.
-*/
-int sqlite3Fts3Incrmerge(Fts3Table *p, int nMerge, int nMin){
- int rc; /* Return code */
- int nRem = nMerge; /* Number of leaf pages yet to be written */
- Fts3MultiSegReader *pCsr; /* Cursor used to read input data */
- Fts3SegFilter *pFilter; /* Filter used with cursor pCsr */
- IncrmergeWriter *pWriter; /* Writer object */
- int nSeg = 0; /* Number of input segments */
- sqlite3_int64 iAbsLevel = 0; /* Absolute level number to work on */
- Blob hint = {0, 0, 0}; /* Hint read from %_stat table */
- int bDirtyHint = 0; /* True if blob 'hint' has been modified */
-
- /* Allocate space for the cursor, filter and writer objects */
- const int nAlloc = sizeof(*pCsr) + sizeof(*pFilter) + sizeof(*pWriter);
- pWriter = (IncrmergeWriter *)sqlite3_malloc(nAlloc);
- if( !pWriter ) return SQLITE_NOMEM;
- pFilter = (Fts3SegFilter *)&pWriter[1];
- pCsr = (Fts3MultiSegReader *)&pFilter[1];
-
- rc = fts3IncrmergeHintLoad(p, &hint);
- while( rc==SQLITE_OK && nRem>0 ){
- const i64 nMod = FTS3_SEGDIR_MAXLEVEL * p->nIndex;
- sqlite3_stmt *pFindLevel = 0; /* SQL used to determine iAbsLevel */
- int bUseHint = 0; /* True if attempting to append */
- int iIdx = 0; /* Largest idx in level (iAbsLevel+1) */
-
- /* Search the %_segdir table for the absolute level with the smallest
- ** relative level number that contains at least nMin segments, if any.
- ** If one is found, set iAbsLevel to the absolute level number and
- ** nSeg to nMin. If no level with at least nMin segments can be found,
- ** set nSeg to -1.
- */
- rc = fts3SqlStmt(p, SQL_FIND_MERGE_LEVEL, &pFindLevel, 0);
- sqlite3_bind_int(pFindLevel, 1, nMin);
- if( sqlite3_step(pFindLevel)==SQLITE_ROW ){
- iAbsLevel = sqlite3_column_int64(pFindLevel, 0);
- nSeg = nMin;
- }else{
- nSeg = -1;
- }
- rc = sqlite3_reset(pFindLevel);
-
- /* If the hint read from the %_stat table is not empty, check if the
- ** last entry in it specifies a relative level smaller than or equal
- ** to the level identified by the block above (if any). If so, this
- ** iteration of the loop will work on merging at the hinted level.
- */
- if( rc==SQLITE_OK && hint.n ){
- int nHint = hint.n;
- sqlite3_int64 iHintAbsLevel = 0; /* Hint level */
- int nHintSeg = 0; /* Hint number of segments */
-
- rc = fts3IncrmergeHintPop(&hint, &iHintAbsLevel, &nHintSeg);
- if( nSeg<0 || (iAbsLevel % nMod) >= (iHintAbsLevel % nMod) ){
- iAbsLevel = iHintAbsLevel;
- nSeg = nHintSeg;
- bUseHint = 1;
- bDirtyHint = 1;
- }else{
- /* This undoes the effect of the HintPop() above - so that no entry
- ** is removed from the hint blob. */
- hint.n = nHint;
- }
- }
-
- /* If nSeg is less that zero, then there is no level with at least
- ** nMin segments and no hint in the %_stat table. No work to do.
- ** Exit early in this case. */
- if( nSeg<0 ) break;
-
- /* Open a cursor to iterate through the contents of the oldest nSeg
- ** indexes of absolute level iAbsLevel. If this cursor is opened using
- ** the 'hint' parameters, it is possible that there are less than nSeg
- ** segments available in level iAbsLevel. In this case, no work is
- ** done on iAbsLevel - fall through to the next iteration of the loop
- ** to start work on some other level. */
- memset(pWriter, 0, nAlloc);
- pFilter->flags = FTS3_SEGMENT_REQUIRE_POS;
-
- if( rc==SQLITE_OK ){
- rc = fts3IncrmergeOutputIdx(p, iAbsLevel, &iIdx);
- assert( bUseHint==1 || bUseHint==0 );
- if( iIdx==0 || (bUseHint && iIdx==1) ){
- int bIgnore = 0;
- rc = fts3SegmentIsMaxLevel(p, iAbsLevel+1, &bIgnore);
- if( bIgnore ){
- pFilter->flags |= FTS3_SEGMENT_IGNORE_EMPTY;
- }
- }
- }
-
- if( rc==SQLITE_OK ){
- rc = fts3IncrmergeCsr(p, iAbsLevel, nSeg, pCsr);
- }
- if( SQLITE_OK==rc && pCsr->nSegment==nSeg
- && SQLITE_OK==(rc = sqlite3Fts3SegReaderStart(p, pCsr, pFilter))
- && SQLITE_ROW==(rc = sqlite3Fts3SegReaderStep(p, pCsr))
- ){
- if( bUseHint && iIdx>0 ){
- const char *zKey = pCsr->zTerm;
- int nKey = pCsr->nTerm;
- rc = fts3IncrmergeLoad(p, iAbsLevel, iIdx-1, zKey, nKey, pWriter);
- }else{
- rc = fts3IncrmergeWriter(p, iAbsLevel, iIdx, pCsr, pWriter);
- }
-
- if( rc==SQLITE_OK && pWriter->nLeafEst ){
- fts3LogMerge(nSeg, iAbsLevel);
- do {
- rc = fts3IncrmergeAppend(p, pWriter, pCsr);
- if( rc==SQLITE_OK ) rc = sqlite3Fts3SegReaderStep(p, pCsr);
- if( pWriter->nWork>=nRem && rc==SQLITE_ROW ) rc = SQLITE_OK;
- }while( rc==SQLITE_ROW );
-
- /* Update or delete the input segments */
- if( rc==SQLITE_OK ){
- nRem -= (1 + pWriter->nWork);
- rc = fts3IncrmergeChomp(p, iAbsLevel, pCsr, &nSeg);
- if( nSeg!=0 ){
- bDirtyHint = 1;
- fts3IncrmergeHintPush(&hint, iAbsLevel, nSeg, &rc);
- }
- }
- }
-
- if( nSeg!=0 ){
- pWriter->nLeafData = pWriter->nLeafData * -1;
- }
- fts3IncrmergeRelease(p, pWriter, &rc);
- if( nSeg==0 && pWriter->bNoLeafData==0 ){
- fts3PromoteSegments(p, iAbsLevel+1, pWriter->nLeafData);
- }
- }
-
- sqlite3Fts3SegReaderFinish(pCsr);
- }
-
- /* Write the hint values into the %_stat table for the next incr-merger */
- if( bDirtyHint && rc==SQLITE_OK ){
- rc = fts3IncrmergeHintStore(p, &hint);
- }
-
- sqlite3_free(pWriter);
- sqlite3_free(hint.a);
- return rc;
-}
-
-/*
-** Convert the text beginning at *pz into an integer and return
-** its value. Advance *pz to point to the first character past
-** the integer.
-*/
-static int fts3Getint(const char **pz){
- const char *z = *pz;
- int i = 0;
- while( (*z)>='0' && (*z)<='9' ) i = 10*i + *(z++) - '0';
- *pz = z;
- return i;
-}
-
-/*
-** Process statements of the form:
-**
-** INSERT INTO table(table) VALUES('merge=A,B');
-**
-** A and B are integers that decode to be the number of leaf pages
-** written for the merge, and the minimum number of segments on a level
-** before it will be selected for a merge, respectively.
-*/
-static int fts3DoIncrmerge(
- Fts3Table *p, /* FTS3 table handle */
- const char *zParam /* Nul-terminated string containing "A,B" */
-){
- int rc;
- int nMin = (FTS3_MERGE_COUNT / 2);
- int nMerge = 0;
- const char *z = zParam;
-
- /* Read the first integer value */
- nMerge = fts3Getint(&z);
-
- /* If the first integer value is followed by a ',', read the second
- ** integer value. */
- if( z[0]==',' && z[1]!='\0' ){
- z++;
- nMin = fts3Getint(&z);
- }
-
- if( z[0]!='\0' || nMin<2 ){
- rc = SQLITE_ERROR;
- }else{
- rc = SQLITE_OK;
- if( !p->bHasStat ){
- assert( p->bFts4==0 );
- sqlite3Fts3CreateStatTable(&rc, p);
- }
- if( rc==SQLITE_OK ){
- rc = sqlite3Fts3Incrmerge(p, nMerge, nMin);
- }
- sqlite3Fts3SegmentsClose(p);
- }
- return rc;
-}
-
-/*
-** Process statements of the form:
-**
-** INSERT INTO table(table) VALUES('automerge=X');
-**
-** where X is an integer. X==0 means to turn automerge off. X!=0 means
-** turn it on. The setting is persistent.
-*/
-static int fts3DoAutoincrmerge(
- Fts3Table *p, /* FTS3 table handle */
- const char *zParam /* Nul-terminated string containing boolean */
-){
- int rc = SQLITE_OK;
- sqlite3_stmt *pStmt = 0;
- p->nAutoincrmerge = fts3Getint(&zParam);
- if( p->nAutoincrmerge==1 || p->nAutoincrmerge>FTS3_MERGE_COUNT ){
- p->nAutoincrmerge = 8;
- }
- if( !p->bHasStat ){
- assert( p->bFts4==0 );
- sqlite3Fts3CreateStatTable(&rc, p);
- if( rc ) return rc;
- }
- rc = fts3SqlStmt(p, SQL_REPLACE_STAT, &pStmt, 0);
- if( rc ) return rc;
- sqlite3_bind_int(pStmt, 1, FTS_STAT_AUTOINCRMERGE);
- sqlite3_bind_int(pStmt, 2, p->nAutoincrmerge);
- sqlite3_step(pStmt);
- rc = sqlite3_reset(pStmt);
- return rc;
-}
-
-/*
-** Return a 64-bit checksum for the FTS index entry specified by the
-** arguments to this function.
-*/
-static u64 fts3ChecksumEntry(
- const char *zTerm, /* Pointer to buffer containing term */
- int nTerm, /* Size of zTerm in bytes */
- int iLangid, /* Language id for current row */
- int iIndex, /* Index (0..Fts3Table.nIndex-1) */
- i64 iDocid, /* Docid for current row. */
- int iCol, /* Column number */
- int iPos /* Position */
-){
- int i;
- u64 ret = (u64)iDocid;
-
- ret += (ret<<3) + iLangid;
- ret += (ret<<3) + iIndex;
- ret += (ret<<3) + iCol;
- ret += (ret<<3) + iPos;
- for(i=0; i<nTerm; i++) ret += (ret<<3) + zTerm[i];
-
- return ret;
-}
-
-/*
-** Return a checksum of all entries in the FTS index that correspond to
-** language id iLangid. The checksum is calculated by XORing the checksums
-** of each individual entry (see fts3ChecksumEntry()) together.
-**
-** If successful, the checksum value is returned and *pRc set to SQLITE_OK.
-** Otherwise, if an error occurs, *pRc is set to an SQLite error code. The
-** return value is undefined in this case.
-*/
-static u64 fts3ChecksumIndex(
- Fts3Table *p, /* FTS3 table handle */
- int iLangid, /* Language id to return cksum for */
- int iIndex, /* Index to cksum (0..p->nIndex-1) */
- int *pRc /* OUT: Return code */
-){
- Fts3SegFilter filter;
- Fts3MultiSegReader csr;
- int rc;
- u64 cksum = 0;
-
- assert( *pRc==SQLITE_OK );
-
- memset(&filter, 0, sizeof(filter));
- memset(&csr, 0, sizeof(csr));
- filter.flags = FTS3_SEGMENT_REQUIRE_POS|FTS3_SEGMENT_IGNORE_EMPTY;
- filter.flags |= FTS3_SEGMENT_SCAN;
-
- rc = sqlite3Fts3SegReaderCursor(
- p, iLangid, iIndex, FTS3_SEGCURSOR_ALL, 0, 0, 0, 1,&csr
- );
- if( rc==SQLITE_OK ){
- rc = sqlite3Fts3SegReaderStart(p, &csr, &filter);
- }
-
- if( rc==SQLITE_OK ){
- while( SQLITE_ROW==(rc = sqlite3Fts3SegReaderStep(p, &csr)) ){
- char *pCsr = csr.aDoclist;
- char *pEnd = &pCsr[csr.nDoclist];
-
- i64 iDocid = 0;
- i64 iCol = 0;
- i64 iPos = 0;
-
- pCsr += sqlite3Fts3GetVarint(pCsr, &iDocid);
- while( pCsr<pEnd ){
- i64 iVal = 0;
- pCsr += sqlite3Fts3GetVarint(pCsr, &iVal);
- if( pCsr<pEnd ){
- if( iVal==0 || iVal==1 ){
- iCol = 0;
- iPos = 0;
- if( iVal ){
- pCsr += sqlite3Fts3GetVarint(pCsr, &iCol);
- }else{
- pCsr += sqlite3Fts3GetVarint(pCsr, &iVal);
- iDocid += iVal;
- }
- }else{
- iPos += (iVal - 2);
- cksum = cksum ^ fts3ChecksumEntry(
- csr.zTerm, csr.nTerm, iLangid, iIndex, iDocid,
- (int)iCol, (int)iPos
- );
- }
- }
- }
- }
- }
- sqlite3Fts3SegReaderFinish(&csr);
-
- *pRc = rc;
- return cksum;
-}
-
-/*
-** Check if the contents of the FTS index match the current contents of the
-** content table. If no error occurs and the contents do match, set *pbOk
-** to true and return SQLITE_OK. Or if the contents do not match, set *pbOk
-** to false before returning.
-**
-** If an error occurs (e.g. an OOM or IO error), return an SQLite error
-** code. The final value of *pbOk is undefined in this case.
-*/
-static int fts3IntegrityCheck(Fts3Table *p, int *pbOk){
- int rc = SQLITE_OK; /* Return code */
- u64 cksum1 = 0; /* Checksum based on FTS index contents */
- u64 cksum2 = 0; /* Checksum based on %_content contents */
- sqlite3_stmt *pAllLangid = 0; /* Statement to return all language-ids */
-
- /* This block calculates the checksum according to the FTS index. */
- rc = fts3SqlStmt(p, SQL_SELECT_ALL_LANGID, &pAllLangid, 0);
- if( rc==SQLITE_OK ){
- int rc2;
- sqlite3_bind_int(pAllLangid, 1, p->nIndex);
- while( rc==SQLITE_OK && sqlite3_step(pAllLangid)==SQLITE_ROW ){
- int iLangid = sqlite3_column_int(pAllLangid, 0);
- int i;
- for(i=0; i<p->nIndex; i++){
- cksum1 = cksum1 ^ fts3ChecksumIndex(p, iLangid, i, &rc);
- }
- }
- rc2 = sqlite3_reset(pAllLangid);
- if( rc==SQLITE_OK ) rc = rc2;
- }
-
- /* This block calculates the checksum according to the %_content table */
- rc = fts3SqlStmt(p, SQL_SELECT_ALL_LANGID, &pAllLangid, 0);
- if( rc==SQLITE_OK ){
- sqlite3_tokenizer_module const *pModule = p->pTokenizer->pModule;
- sqlite3_stmt *pStmt = 0;
- char *zSql;
-
- zSql = sqlite3_mprintf("SELECT %s" , p->zReadExprlist);
- if( !zSql ){
- rc = SQLITE_NOMEM;
- }else{
- rc = sqlite3_prepare_v2(p->db, zSql, -1, &pStmt, 0);
- sqlite3_free(zSql);
- }
-
- while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){
- i64 iDocid = sqlite3_column_int64(pStmt, 0);
- int iLang = langidFromSelect(p, pStmt);
- int iCol;
-
- for(iCol=0; rc==SQLITE_OK && iCol<p->nColumn; iCol++){
- if( p->abNotindexed[iCol]==0 ){
- const char *zText = (const char *)sqlite3_column_text(pStmt, iCol+1);
- int nText = sqlite3_column_bytes(pStmt, iCol+1);
- sqlite3_tokenizer_cursor *pT = 0;
-
- rc = sqlite3Fts3OpenTokenizer(p->pTokenizer, iLang, zText, nText,&pT);
- while( rc==SQLITE_OK ){
- char const *zToken; /* Buffer containing token */
- int nToken = 0; /* Number of bytes in token */
- int iDum1 = 0, iDum2 = 0; /* Dummy variables */
- int iPos = 0; /* Position of token in zText */
-
- rc = pModule->xNext(pT, &zToken, &nToken, &iDum1, &iDum2, &iPos);
- if( rc==SQLITE_OK ){
- int i;
- cksum2 = cksum2 ^ fts3ChecksumEntry(
- zToken, nToken, iLang, 0, iDocid, iCol, iPos
- );
- for(i=1; i<p->nIndex; i++){
- if( p->aIndex[i].nPrefix<=nToken ){
- cksum2 = cksum2 ^ fts3ChecksumEntry(
- zToken, p->aIndex[i].nPrefix, iLang, i, iDocid, iCol, iPos
- );
- }
- }
- }
- }
- if( pT ) pModule->xClose(pT);
- if( rc==SQLITE_DONE ) rc = SQLITE_OK;
- }
- }
- }
-
- sqlite3_finalize(pStmt);
- }
-
- *pbOk = (cksum1==cksum2);
- return rc;
-}
-
-/*
-** Run the integrity-check. If no error occurs and the current contents of
-** the FTS index are correct, return SQLITE_OK. Or, if the contents of the
-** FTS index are incorrect, return SQLITE_CORRUPT_VTAB.
-**
-** Or, if an error (e.g. an OOM or IO error) occurs, return an SQLite
-** error code.
-**
-** The integrity-check works as follows. For each token and indexed token
-** prefix in the document set, a 64-bit checksum is calculated (by code
-** in fts3ChecksumEntry()) based on the following:
-**
-** + The index number (0 for the main index, 1 for the first prefix
-** index etc.),
-** + The token (or token prefix) text itself,
-** + The language-id of the row it appears in,
-** + The docid of the row it appears in,
-** + The column it appears in, and
-** + The tokens position within that column.
-**
-** The checksums for all entries in the index are XORed together to create
-** a single checksum for the entire index.
-**
-** The integrity-check code calculates the same checksum in two ways:
-**
-** 1. By scanning the contents of the FTS index, and
-** 2. By scanning and tokenizing the content table.
-**
-** If the two checksums are identical, the integrity-check is deemed to have
-** passed.
-*/
-static int fts3DoIntegrityCheck(
- Fts3Table *p /* FTS3 table handle */
-){
- int rc;
- int bOk = 0;
- rc = fts3IntegrityCheck(p, &bOk);
- if( rc==SQLITE_OK && bOk==0 ) rc = SQLITE_CORRUPT_VTAB;
- return rc;
-}
-
-/*
-** Handle a 'special' INSERT of the form:
-**
-** "INSERT INTO tbl(tbl) VALUES(<expr>)"
-**
-** Argument pVal contains the result of <expr>. Currently the only
-** meaningful value to insert is the text 'optimize'.
-*/
-static int fts3SpecialInsert(Fts3Table *p, sqlite3_value *pVal){
- int rc; /* Return Code */
- const char *zVal = (const char *)sqlite3_value_text(pVal);
- int nVal = sqlite3_value_bytes(pVal);
-
- if( !zVal ){
- return SQLITE_NOMEM;
- }else if( nVal==8 && 0==sqlite3_strnicmp(zVal, "optimize", 8) ){
- rc = fts3DoOptimize(p, 0);
- }else if( nVal==7 && 0==sqlite3_strnicmp(zVal, "rebuild", 7) ){
- rc = fts3DoRebuild(p);
- }else if( nVal==15 && 0==sqlite3_strnicmp(zVal, "integrity-check", 15) ){
- rc = fts3DoIntegrityCheck(p);
- }else if( nVal>6 && 0==sqlite3_strnicmp(zVal, "merge=", 6) ){
- rc = fts3DoIncrmerge(p, &zVal[6]);
- }else if( nVal>10 && 0==sqlite3_strnicmp(zVal, "automerge=", 10) ){
- rc = fts3DoAutoincrmerge(p, &zVal[10]);
-#ifdef SQLITE_TEST
- }else if( nVal>9 && 0==sqlite3_strnicmp(zVal, "nodesize=", 9) ){
- p->nNodeSize = atoi(&zVal[9]);
- rc = SQLITE_OK;
- }else if( nVal>11 && 0==sqlite3_strnicmp(zVal, "maxpending=", 9) ){
- p->nMaxPendingData = atoi(&zVal[11]);
- rc = SQLITE_OK;
- }else if( nVal>21 && 0==sqlite3_strnicmp(zVal, "test-no-incr-doclist=", 21) ){
- p->bNoIncrDoclist = atoi(&zVal[21]);
- rc = SQLITE_OK;
-#endif
- }else{
- rc = SQLITE_ERROR;
- }
-
- return rc;
-}
-
-#ifndef SQLITE_DISABLE_FTS4_DEFERRED
-/*
-** Delete all cached deferred doclists. Deferred doclists are cached
-** (allocated) by the sqlite3Fts3CacheDeferredDoclists() function.
-*/
-void sqlite3Fts3FreeDeferredDoclists(Fts3Cursor *pCsr){
- Fts3DeferredToken *pDef;
- for(pDef=pCsr->pDeferred; pDef; pDef=pDef->pNext){
- fts3PendingListDelete(pDef->pList);
- pDef->pList = 0;
- }
-}
-
-/*
-** Free all entries in the pCsr->pDeffered list. Entries are added to
-** this list using sqlite3Fts3DeferToken().
-*/
-void sqlite3Fts3FreeDeferredTokens(Fts3Cursor *pCsr){
- Fts3DeferredToken *pDef;
- Fts3DeferredToken *pNext;
- for(pDef=pCsr->pDeferred; pDef; pDef=pNext){
- pNext = pDef->pNext;
- fts3PendingListDelete(pDef->pList);
- sqlite3_free(pDef);
- }
- pCsr->pDeferred = 0;
-}
-
-/*
-** Generate deferred-doclists for all tokens in the pCsr->pDeferred list
-** based on the row that pCsr currently points to.
-**
-** A deferred-doclist is like any other doclist with position information
-** included, except that it only contains entries for a single row of the
-** table, not for all rows.
-*/
-int sqlite3Fts3CacheDeferredDoclists(Fts3Cursor *pCsr){
- int rc = SQLITE_OK; /* Return code */
- if( pCsr->pDeferred ){
- int i; /* Used to iterate through table columns */
- sqlite3_int64 iDocid; /* Docid of the row pCsr points to */
- Fts3DeferredToken *pDef; /* Used to iterate through deferred tokens */
-
- Fts3Table *p = (Fts3Table *)pCsr->base.pVtab;
- sqlite3_tokenizer *pT = p->pTokenizer;
- sqlite3_tokenizer_module const *pModule = pT->pModule;
-
- assert( pCsr->isRequireSeek==0 );
- iDocid = sqlite3_column_int64(pCsr->pStmt, 0);
-
- for(i=0; i<p->nColumn && rc==SQLITE_OK; i++){
- if( p->abNotindexed[i]==0 ){
- const char *zText = (const char *)sqlite3_column_text(pCsr->pStmt, i+1);
- sqlite3_tokenizer_cursor *pTC = 0;
-
- rc = sqlite3Fts3OpenTokenizer(pT, pCsr->iLangid, zText, -1, &pTC);
- while( rc==SQLITE_OK ){
- char const *zToken; /* Buffer containing token */
- int nToken = 0; /* Number of bytes in token */
- int iDum1 = 0, iDum2 = 0; /* Dummy variables */
- int iPos = 0; /* Position of token in zText */
-
- rc = pModule->xNext(pTC, &zToken, &nToken, &iDum1, &iDum2, &iPos);
- for(pDef=pCsr->pDeferred; pDef && rc==SQLITE_OK; pDef=pDef->pNext){
- Fts3PhraseToken *pPT = pDef->pToken;
- if( (pDef->iCol>=p->nColumn || pDef->iCol==i)
- && (pPT->bFirst==0 || iPos==0)
- && (pPT->n==nToken || (pPT->isPrefix && pPT->n<nToken))
- && (0==memcmp(zToken, pPT->z, pPT->n))
- ){
- fts3PendingListAppend(&pDef->pList, iDocid, i, iPos, &rc);
- }
- }
- }
- if( pTC ) pModule->xClose(pTC);
- if( rc==SQLITE_DONE ) rc = SQLITE_OK;
- }
- }
-
- for(pDef=pCsr->pDeferred; pDef && rc==SQLITE_OK; pDef=pDef->pNext){
- if( pDef->pList ){
- rc = fts3PendingListAppendVarint(&pDef->pList, 0);
- }
- }
- }
-
- return rc;
-}
-
-int sqlite3Fts3DeferredTokenList(
- Fts3DeferredToken *p,
- char **ppData,
- int *pnData
-){
- char *pRet;
- int nSkip;
- sqlite3_int64 dummy;
-
- *ppData = 0;
- *pnData = 0;
-
- if( p->pList==0 ){
- return SQLITE_OK;
- }
-
- pRet = (char *)sqlite3_malloc(p->pList->nData);
- if( !pRet ) return SQLITE_NOMEM;
-
- nSkip = sqlite3Fts3GetVarint(p->pList->aData, &dummy);
- *pnData = p->pList->nData - nSkip;
- *ppData = pRet;
-
- memcpy(pRet, &p->pList->aData[nSkip], *pnData);
- return SQLITE_OK;
-}
-
-/*
-** Add an entry for token pToken to the pCsr->pDeferred list.
-*/
-int sqlite3Fts3DeferToken(
- Fts3Cursor *pCsr, /* Fts3 table cursor */
- Fts3PhraseToken *pToken, /* Token to defer */
- int iCol /* Column that token must appear in (or -1) */
-){
- Fts3DeferredToken *pDeferred;
- pDeferred = sqlite3_malloc(sizeof(*pDeferred));
- if( !pDeferred ){
- return SQLITE_NOMEM;
- }
- memset(pDeferred, 0, sizeof(*pDeferred));
- pDeferred->pToken = pToken;
- pDeferred->pNext = pCsr->pDeferred;
- pDeferred->iCol = iCol;
- pCsr->pDeferred = pDeferred;
-
- assert( pToken->pDeferred==0 );
- pToken->pDeferred = pDeferred;
-
- return SQLITE_OK;
-}
-#endif
-
-/*
-** SQLite value pRowid contains the rowid of a row that may or may not be
-** present in the FTS3 table. If it is, delete it and adjust the contents
-** of subsiduary data structures accordingly.
-*/
-static int fts3DeleteByRowid(
- Fts3Table *p,
- sqlite3_value *pRowid,
- int *pnChng, /* IN/OUT: Decrement if row is deleted */
- u32 *aSzDel
-){
- int rc = SQLITE_OK; /* Return code */
- int bFound = 0; /* True if *pRowid really is in the table */
-
- fts3DeleteTerms(&rc, p, pRowid, aSzDel, &bFound);
- if( bFound && rc==SQLITE_OK ){
- int isEmpty = 0; /* Deleting *pRowid leaves the table empty */
- rc = fts3IsEmpty(p, pRowid, &isEmpty);
- if( rc==SQLITE_OK ){
- if( isEmpty ){
- /* Deleting this row means the whole table is empty. In this case
- ** delete the contents of all three tables and throw away any
- ** data in the pendingTerms hash table. */
- rc = fts3DeleteAll(p, 1);
- *pnChng = 0;
- memset(aSzDel, 0, sizeof(u32) * (p->nColumn+1) * 2);
- }else{
- *pnChng = *pnChng - 1;
- if( p->zContentTbl==0 ){
- fts3SqlExec(&rc, p, SQL_DELETE_CONTENT, &pRowid);
- }
- if( p->bHasDocsize ){
- fts3SqlExec(&rc, p, SQL_DELETE_DOCSIZE, &pRowid);
- }
- }
- }
- }
-
- return rc;
-}
-
-/*
-** This function does the work for the xUpdate method of FTS3 virtual
-** tables. The schema of the virtual table being:
-**
-** CREATE TABLE <table name>(
-** <user columns>,
-** <table name> HIDDEN,
-** docid HIDDEN,
-** <langid> HIDDEN
-** );
-**
-**
-*/
-int sqlite3Fts3UpdateMethod(
- sqlite3_vtab *pVtab, /* FTS3 vtab object */
- 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 = 0; /* Sizes of deleted documents */
- int nChng = 0; /* Net change in number of documents */
- int bInsertDone = 0;
-
- /* At this point it must be known if the %_stat table exists or not.
- ** So bHasStat may not be 2. */
- assert( p->bHasStat==0 || p->bHasStat==1 );
-
- assert( p->pSegments==0 );
- assert(
- nArg==1 /* DELETE operations */
- || nArg==(2 + p->nColumn + 3) /* INSERT or UPDATE operations */
- );
-
- /* Check for a "special" INSERT operation. One of the form:
- **
- ** INSERT INTO xyz(xyz) VALUES('command');
- */
- if( nArg>1
- && sqlite3_value_type(apVal[0])==SQLITE_NULL
- && sqlite3_value_type(apVal[p->nColumn+2])!=SQLITE_NULL
- ){
- rc = fts3SpecialInsert(p, apVal[p->nColumn+2]);
- goto update_out;
- }
-
- if( nArg>1 && sqlite3_value_int(apVal[2 + p->nColumn + 2])<0 ){
- rc = SQLITE_CONSTRAINT;
- goto update_out;
- }
-
- /* Allocate space to hold the change in document sizes */
- aSzDel = sqlite3_malloc( sizeof(aSzDel[0])*(p->nColumn+1)*2 );
- if( aSzDel==0 ){
- rc = SQLITE_NOMEM;
- goto update_out;
- }
- aSzIns = &aSzDel[p->nColumn+1];
- memset(aSzDel, 0, sizeof(aSzDel[0])*(p->nColumn+1)*2);
-
- rc = fts3Writelock(p);
- if( rc!=SQLITE_OK ) goto update_out;
-
- /* If this is an INSERT operation, or an UPDATE that modifies the rowid
- ** value, then this operation requires constraint handling.
- **
- ** If the on-conflict mode is REPLACE, this means that the existing row
- ** should be deleted from the database before inserting the new row. Or,
- ** if the on-conflict mode is other than REPLACE, then this method must
- ** detect the conflict and return SQLITE_CONSTRAINT before beginning to
- ** modify the database file.
- */
- if( nArg>1 && p->zContentTbl==0 ){
- /* Find the value object that holds the new rowid value. */
- sqlite3_value *pNewRowid = apVal[3+p->nColumn];
- if( sqlite3_value_type(pNewRowid)==SQLITE_NULL ){
- pNewRowid = apVal[1];
- }
-
- if( sqlite3_value_type(pNewRowid)!=SQLITE_NULL && (
- sqlite3_value_type(apVal[0])==SQLITE_NULL
- || sqlite3_value_int64(apVal[0])!=sqlite3_value_int64(pNewRowid)
- )){
- /* The new rowid is not NULL (in this case the rowid will be
- ** automatically assigned and there is no chance of a conflict), and
- ** the statement is either an INSERT or an UPDATE that modifies the
- ** rowid column. So if the conflict mode is REPLACE, then delete any
- ** existing row with rowid=pNewRowid.
- **
- ** Or, if the conflict mode is not REPLACE, insert the new record into
- ** the %_content table. If we hit the duplicate rowid constraint (or any
- ** other error) while doing so, return immediately.
- **
- ** This branch may also run if pNewRowid contains a value that cannot
- ** be losslessly converted to an integer. In this case, the eventual
- ** call to fts3InsertData() (either just below or further on in this
- ** function) will return SQLITE_MISMATCH. If fts3DeleteByRowid is
- ** invoked, it will delete zero rows (since no row will have
- ** docid=$pNewRowid if $pNewRowid is not an integer value).
- */
- if( sqlite3_vtab_on_conflict(p->db)==SQLITE_REPLACE ){
- rc = fts3DeleteByRowid(p, pNewRowid, &nChng, aSzDel);
- }else{
- rc = fts3InsertData(p, apVal, pRowid);
- bInsertDone = 1;
- }
- }
- }
- if( rc!=SQLITE_OK ){
- goto update_out;
- }
-
- /* 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 ){
- int iLangid = sqlite3_value_int(apVal[2 + p->nColumn + 2]);
- if( bInsertDone==0 ){
- rc = fts3InsertData(p, apVal, pRowid);
- if( rc==SQLITE_CONSTRAINT && p->zContentTbl==0 ){
- rc = FTS_CORRUPT_VTAB;
- }
- }
- if( rc==SQLITE_OK && (!isRemove || *pRowid!=p->iPrevDocid ) ){
- rc = fts3PendingTermsDocid(p, iLangid, *pRowid);
- }
- if( rc==SQLITE_OK ){
- assert( p->iPrevDocid==*pRowid );
- rc = fts3InsertTerms(p, iLangid, apVal, aSzIns);
- }
- if( p->bHasDocsize ){
- fts3InsertDocsize(&rc, p, aSzIns);
- }
- nChng++;
- }
-
- if( p->bFts4 ){
- fts3UpdateDocTotals(&rc, p, aSzIns, aSzDel, nChng);
- }
-
- update_out:
- sqlite3_free(aSzDel);
- sqlite3Fts3SegmentsClose(p);
- return rc;
-}
-
-/*
-** Flush any data in the pending-terms hash table to disk. If successful,
-** merge all segments in the database (including the new segment, if
-** there was any data to flush) into a single segment.
-*/
-int sqlite3Fts3Optimize(Fts3Table *p){
- int rc;
- rc = sqlite3_exec(p->db, "SAVEPOINT fts3", 0, 0, 0);
- if( rc==SQLITE_OK ){
- rc = fts3DoOptimize(p, 1);
- if( rc==SQLITE_OK || rc==SQLITE_DONE ){
- int rc2 = sqlite3_exec(p->db, "RELEASE fts3", 0, 0, 0);
- if( rc2!=SQLITE_OK ) rc = rc2;
- }else{
- sqlite3_exec(p->db, "ROLLBACK TO fts3", 0, 0, 0);
- sqlite3_exec(p->db, "RELEASE fts3", 0, 0, 0);
- }
- }
- sqlite3Fts3SegmentsClose(p);
- return rc;
-}
-
-#endif

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