Index: third_party/sqlite/sqlite-src-3080704/ext/fts1/fts1.c |
diff --git a/third_party/sqlite/sqlite-src-3080704/ext/fts1/fts1.c b/third_party/sqlite/sqlite-src-3080704/ext/fts1/fts1.c |
deleted file mode 100644 |
index 482cf759ba1d176e004dc0c33ab08a6cc8297665..0000000000000000000000000000000000000000 |
--- a/third_party/sqlite/sqlite-src-3080704/ext/fts1/fts1.c |
+++ /dev/null |
@@ -1,3348 +0,0 @@ |
-/* fts1 has a design flaw which can lead to database corruption (see |
-** below). It is recommended not to use it any longer, instead use |
-** fts3 (or higher). If you believe that your use of fts1 is safe, |
-** add -DSQLITE_ENABLE_BROKEN_FTS1=1 to your CFLAGS. |
-*/ |
-#if (!defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS1)) \ |
- && !defined(SQLITE_ENABLE_BROKEN_FTS1) |
-#error fts1 has a design flaw and has been deprecated. |
-#endif |
-/* The flaw is that fts1 uses the content table's unaliased rowid as |
-** the unique docid. fts1 embeds the rowid in the index it builds, |
-** and expects the rowid to not change. The SQLite VACUUM operation |
-** will renumber such rowids, thereby breaking fts1. If you are using |
-** fts1 in a system which has disabled VACUUM, then you can continue |
-** to use it safely. Note that PRAGMA auto_vacuum does NOT disable |
-** VACUUM, though systems using auto_vacuum are unlikely to invoke |
-** VACUUM. |
-** |
-** fts1 should be safe even across VACUUM if you only insert documents |
-** and never delete. |
-*/ |
- |
-/* The author disclaims copyright to this source code. |
- * |
- * This is an SQLite module implementing full-text search. |
- */ |
- |
-/* |
-** The code in this file is only compiled if: |
-** |
-** * The FTS1 module is being built as an extension |
-** (in which case SQLITE_CORE is not defined), or |
-** |
-** * The FTS1 module is being built into the core of |
-** SQLite (in which case SQLITE_ENABLE_FTS1 is defined). |
-*/ |
-#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS1) |
- |
-#if defined(SQLITE_ENABLE_FTS1) && !defined(SQLITE_CORE) |
-# define SQLITE_CORE 1 |
-#endif |
- |
-#include <assert.h> |
-#include <stdlib.h> |
-#include <stdio.h> |
-#include <string.h> |
-#include <ctype.h> |
- |
-#include "fts1.h" |
-#include "fts1_hash.h" |
-#include "fts1_tokenizer.h" |
-#include "sqlite3.h" |
-#include "sqlite3ext.h" |
-SQLITE_EXTENSION_INIT1 |
- |
- |
-#if 0 |
-# define TRACE(A) printf A; fflush(stdout) |
-#else |
-# define TRACE(A) |
-#endif |
- |
-/* utility functions */ |
- |
-typedef struct StringBuffer { |
- int len; /* length, not including null terminator */ |
- int alloced; /* Space allocated for s[] */ |
- char *s; /* Content of the string */ |
-} StringBuffer; |
- |
-static void initStringBuffer(StringBuffer *sb){ |
- sb->len = 0; |
- sb->alloced = 100; |
- sb->s = malloc(100); |
- sb->s[0] = '\0'; |
-} |
- |
-static void nappend(StringBuffer *sb, const char *zFrom, int nFrom){ |
- if( sb->len + nFrom >= sb->alloced ){ |
- sb->alloced = sb->len + nFrom + 100; |
- sb->s = realloc(sb->s, sb->alloced+1); |
- if( sb->s==0 ){ |
- initStringBuffer(sb); |
- return; |
- } |
- } |
- memcpy(sb->s + sb->len, zFrom, nFrom); |
- sb->len += nFrom; |
- sb->s[sb->len] = 0; |
-} |
-static void append(StringBuffer *sb, const char *zFrom){ |
- nappend(sb, zFrom, strlen(zFrom)); |
-} |
- |
-/* We encode variable-length integers in little-endian order using seven bits |
- * per byte as follows: |
-** |
-** KEY: |
-** A = 0xxxxxxx 7 bits of data and one flag bit |
-** B = 1xxxxxxx 7 bits of data and one flag bit |
-** |
-** 7 bits - A |
-** 14 bits - BA |
-** 21 bits - BBA |
-** and so on. |
-*/ |
- |
-/* We may need up to VARINT_MAX bytes to store an encoded 64-bit integer. */ |
-#define VARINT_MAX 10 |
- |
-/* Write a 64-bit variable-length integer to memory starting at p[0]. |
- * The length of data written will be between 1 and VARINT_MAX bytes. |
- * The number of bytes written is returned. */ |
-static int putVarint(char *p, sqlite_int64 v){ |
- unsigned char *q = (unsigned char *) p; |
- sqlite_uint64 vu = v; |
- do{ |
- *q++ = (unsigned char) ((vu & 0x7f) | 0x80); |
- vu >>= 7; |
- }while( vu!=0 ); |
- q[-1] &= 0x7f; /* turn off high bit in final byte */ |
- assert( q - (unsigned char *)p <= VARINT_MAX ); |
- return (int) (q - (unsigned char *)p); |
-} |
- |
-/* Read a 64-bit variable-length integer from memory starting at p[0]. |
- * Return the number of bytes read, or 0 on error. |
- * The value is stored in *v. */ |
-static int getVarint(const char *p, sqlite_int64 *v){ |
- const unsigned char *q = (const unsigned char *) p; |
- sqlite_uint64 x = 0, y = 1; |
- while( (*q & 0x80) == 0x80 ){ |
- x += y * (*q++ & 0x7f); |
- y <<= 7; |
- if( q - (unsigned char *)p >= VARINT_MAX ){ /* bad data */ |
- assert( 0 ); |
- return 0; |
- } |
- } |
- x += y * (*q++); |
- *v = (sqlite_int64) x; |
- return (int) (q - (unsigned char *)p); |
-} |
- |
-static int getVarint32(const char *p, int *pi){ |
- sqlite_int64 i; |
- int ret = getVarint(p, &i); |
- *pi = (int) i; |
- assert( *pi==i ); |
- return ret; |
-} |
- |
-/*** Document lists *** |
- * |
- * A document list holds a sorted list of varint-encoded document IDs. |
- * |
- * A doclist with type DL_POSITIONS_OFFSETS is stored like this: |
- * |
- * array { |
- * varint docid; |
- * array { |
- * varint position; (delta from previous position plus POS_BASE) |
- * varint startOffset; (delta from previous startOffset) |
- * varint endOffset; (delta from startOffset) |
- * } |
- * } |
- * |
- * Here, array { X } means zero or more occurrences of X, adjacent in memory. |
- * |
- * A position list may hold positions for text in multiple columns. A position |
- * POS_COLUMN is followed by a varint containing the index of the column for |
- * following positions in the list. Any positions appearing before any |
- * occurrences of POS_COLUMN are for column 0. |
- * |
- * A doclist with type DL_POSITIONS is like the above, but holds only docids |
- * and positions without offset information. |
- * |
- * A doclist with type DL_DOCIDS is like the above, but holds only docids |
- * without positions or offset information. |
- * |
- * On disk, every document list has positions and offsets, so we don't bother |
- * to serialize a doclist's type. |
- * |
- * We don't yet delta-encode document IDs; doing so will probably be a |
- * modest win. |
- * |
- * NOTE(shess) I've thought of a slightly (1%) better offset encoding. |
- * After the first offset, estimate the next offset by using the |
- * current token position and the previous token position and offset, |
- * offset to handle some variance. So the estimate would be |
- * (iPosition*w->iStartOffset/w->iPosition-64), which is delta-encoded |
- * as normal. Offsets more than 64 chars from the estimate are |
- * encoded as the delta to the previous start offset + 128. An |
- * additional tiny increment can be gained by using the end offset of |
- * the previous token to make the estimate a tiny bit more precise. |
-*/ |
- |
-/* It is not safe to call isspace(), tolower(), or isalnum() on |
-** hi-bit-set characters. This is the same solution used in the |
-** tokenizer. |
-*/ |
-/* TODO(shess) The snippet-generation code should be using the |
-** tokenizer-generated tokens rather than doing its own local |
-** tokenization. |
-*/ |
-/* TODO(shess) Is __isascii() a portable version of (c&0x80)==0? */ |
-static int safe_isspace(char c){ |
- return (c&0x80)==0 ? isspace(c) : 0; |
-} |
-static int safe_tolower(char c){ |
- return (c&0x80)==0 ? tolower(c) : c; |
-} |
-static int safe_isalnum(char c){ |
- return (c&0x80)==0 ? isalnum(c) : 0; |
-} |
- |
-typedef enum DocListType { |
- DL_DOCIDS, /* docids only */ |
- DL_POSITIONS, /* docids + positions */ |
- DL_POSITIONS_OFFSETS /* docids + positions + offsets */ |
-} DocListType; |
- |
-/* |
-** By default, only positions and not offsets are stored in the doclists. |
-** To change this so that offsets are stored too, compile with |
-** |
-** -DDL_DEFAULT=DL_POSITIONS_OFFSETS |
-** |
-*/ |
-#ifndef DL_DEFAULT |
-# define DL_DEFAULT DL_POSITIONS |
-#endif |
- |
-typedef struct DocList { |
- char *pData; |
- int nData; |
- DocListType iType; |
- int iLastColumn; /* the last column written */ |
- int iLastPos; /* the last position written */ |
- int iLastOffset; /* the last start offset written */ |
-} DocList; |
- |
-enum { |
- POS_END = 0, /* end of this position list */ |
- POS_COLUMN, /* followed by new column number */ |
- POS_BASE |
-}; |
- |
-/* Initialize a new DocList to hold the given data. */ |
-static void docListInit(DocList *d, DocListType iType, |
- const char *pData, int nData){ |
- d->nData = nData; |
- if( nData>0 ){ |
- d->pData = malloc(nData); |
- memcpy(d->pData, pData, nData); |
- } else { |
- d->pData = NULL; |
- } |
- d->iType = iType; |
- d->iLastColumn = 0; |
- d->iLastPos = d->iLastOffset = 0; |
-} |
- |
-/* Create a new dynamically-allocated DocList. */ |
-static DocList *docListNew(DocListType iType){ |
- DocList *d = (DocList *) malloc(sizeof(DocList)); |
- docListInit(d, iType, 0, 0); |
- return d; |
-} |
- |
-static void docListDestroy(DocList *d){ |
- free(d->pData); |
-#ifndef NDEBUG |
- memset(d, 0x55, sizeof(*d)); |
-#endif |
-} |
- |
-static void docListDelete(DocList *d){ |
- docListDestroy(d); |
- free(d); |
-} |
- |
-static char *docListEnd(DocList *d){ |
- return d->pData + d->nData; |
-} |
- |
-/* Append a varint to a DocList's data. */ |
-static void appendVarint(DocList *d, sqlite_int64 i){ |
- char c[VARINT_MAX]; |
- int n = putVarint(c, i); |
- d->pData = realloc(d->pData, d->nData + n); |
- memcpy(d->pData + d->nData, c, n); |
- d->nData += n; |
-} |
- |
-static void docListAddDocid(DocList *d, sqlite_int64 iDocid){ |
- appendVarint(d, iDocid); |
- if( d->iType>=DL_POSITIONS ){ |
- appendVarint(d, POS_END); /* initially empty position list */ |
- d->iLastColumn = 0; |
- d->iLastPos = d->iLastOffset = 0; |
- } |
-} |
- |
-/* helper function for docListAddPos and docListAddPosOffset */ |
-static void addPos(DocList *d, int iColumn, int iPos){ |
- assert( d->nData>0 ); |
- --d->nData; /* remove previous terminator */ |
- if( iColumn!=d->iLastColumn ){ |
- assert( iColumn>d->iLastColumn ); |
- appendVarint(d, POS_COLUMN); |
- appendVarint(d, iColumn); |
- d->iLastColumn = iColumn; |
- d->iLastPos = d->iLastOffset = 0; |
- } |
- assert( iPos>=d->iLastPos ); |
- appendVarint(d, iPos-d->iLastPos+POS_BASE); |
- d->iLastPos = iPos; |
-} |
- |
-/* Add a position to the last position list in a doclist. */ |
-static void docListAddPos(DocList *d, int iColumn, int iPos){ |
- assert( d->iType==DL_POSITIONS ); |
- addPos(d, iColumn, iPos); |
- appendVarint(d, POS_END); /* add new terminator */ |
-} |
- |
-/* |
-** Add a position and starting and ending offsets to a doclist. |
-** |
-** If the doclist is setup to handle only positions, then insert |
-** the position only and ignore the offsets. |
-*/ |
-static void docListAddPosOffset( |
- DocList *d, /* Doclist under construction */ |
- int iColumn, /* Column the inserted term is part of */ |
- int iPos, /* Position of the inserted term */ |
- int iStartOffset, /* Starting offset of inserted term */ |
- int iEndOffset /* Ending offset of inserted term */ |
-){ |
- assert( d->iType>=DL_POSITIONS ); |
- addPos(d, iColumn, iPos); |
- if( d->iType==DL_POSITIONS_OFFSETS ){ |
- assert( iStartOffset>=d->iLastOffset ); |
- appendVarint(d, iStartOffset-d->iLastOffset); |
- d->iLastOffset = iStartOffset; |
- assert( iEndOffset>=iStartOffset ); |
- appendVarint(d, iEndOffset-iStartOffset); |
- } |
- appendVarint(d, POS_END); /* add new terminator */ |
-} |
- |
-/* |
-** A DocListReader object is a cursor into a doclist. Initialize |
-** the cursor to the beginning of the doclist by calling readerInit(). |
-** Then use routines |
-** |
-** peekDocid() |
-** readDocid() |
-** readPosition() |
-** skipPositionList() |
-** and so forth... |
-** |
-** to read information out of the doclist. When we reach the end |
-** of the doclist, atEnd() returns TRUE. |
-*/ |
-typedef struct DocListReader { |
- DocList *pDoclist; /* The document list we are stepping through */ |
- char *p; /* Pointer to next unread byte in the doclist */ |
- int iLastColumn; |
- int iLastPos; /* the last position read, or -1 when not in a position list */ |
-} DocListReader; |
- |
-/* |
-** Initialize the DocListReader r to point to the beginning of pDoclist. |
-*/ |
-static void readerInit(DocListReader *r, DocList *pDoclist){ |
- r->pDoclist = pDoclist; |
- if( pDoclist!=NULL ){ |
- r->p = pDoclist->pData; |
- } |
- r->iLastColumn = -1; |
- r->iLastPos = -1; |
-} |
- |
-/* |
-** Return TRUE if we have reached then end of pReader and there is |
-** nothing else left to read. |
-*/ |
-static int atEnd(DocListReader *pReader){ |
- return pReader->pDoclist==0 || (pReader->p >= docListEnd(pReader->pDoclist)); |
-} |
- |
-/* Peek at the next docid without advancing the read pointer. |
-*/ |
-static sqlite_int64 peekDocid(DocListReader *pReader){ |
- sqlite_int64 ret; |
- assert( !atEnd(pReader) ); |
- assert( pReader->iLastPos==-1 ); |
- getVarint(pReader->p, &ret); |
- return ret; |
-} |
- |
-/* Read the next docid. See also nextDocid(). |
-*/ |
-static sqlite_int64 readDocid(DocListReader *pReader){ |
- sqlite_int64 ret; |
- assert( !atEnd(pReader) ); |
- assert( pReader->iLastPos==-1 ); |
- pReader->p += getVarint(pReader->p, &ret); |
- if( pReader->pDoclist->iType>=DL_POSITIONS ){ |
- pReader->iLastColumn = 0; |
- pReader->iLastPos = 0; |
- } |
- return ret; |
-} |
- |
-/* Read the next position and column index from a position list. |
- * Returns the position, or -1 at the end of the list. */ |
-static int readPosition(DocListReader *pReader, int *iColumn){ |
- int i; |
- int iType = pReader->pDoclist->iType; |
- |
- if( pReader->iLastPos==-1 ){ |
- return -1; |
- } |
- assert( !atEnd(pReader) ); |
- |
- if( iType<DL_POSITIONS ){ |
- return -1; |
- } |
- pReader->p += getVarint32(pReader->p, &i); |
- if( i==POS_END ){ |
- pReader->iLastColumn = pReader->iLastPos = -1; |
- *iColumn = -1; |
- return -1; |
- } |
- if( i==POS_COLUMN ){ |
- pReader->p += getVarint32(pReader->p, &pReader->iLastColumn); |
- pReader->iLastPos = 0; |
- pReader->p += getVarint32(pReader->p, &i); |
- assert( i>=POS_BASE ); |
- } |
- pReader->iLastPos += ((int) i)-POS_BASE; |
- if( iType>=DL_POSITIONS_OFFSETS ){ |
- /* Skip over offsets, ignoring them for now. */ |
- int iStart, iEnd; |
- pReader->p += getVarint32(pReader->p, &iStart); |
- pReader->p += getVarint32(pReader->p, &iEnd); |
- } |
- *iColumn = pReader->iLastColumn; |
- return pReader->iLastPos; |
-} |
- |
-/* Skip past the end of a position list. */ |
-static void skipPositionList(DocListReader *pReader){ |
- DocList *p = pReader->pDoclist; |
- if( p && p->iType>=DL_POSITIONS ){ |
- int iColumn; |
- while( readPosition(pReader, &iColumn)!=-1 ){} |
- } |
-} |
- |
-/* Skip over a docid, including its position list if the doclist has |
- * positions. */ |
-static void skipDocument(DocListReader *pReader){ |
- readDocid(pReader); |
- skipPositionList(pReader); |
-} |
- |
-/* Skip past all docids which are less than [iDocid]. Returns 1 if a docid |
- * matching [iDocid] was found. */ |
-static int skipToDocid(DocListReader *pReader, sqlite_int64 iDocid){ |
- sqlite_int64 d = 0; |
- while( !atEnd(pReader) && (d=peekDocid(pReader))<iDocid ){ |
- skipDocument(pReader); |
- } |
- return !atEnd(pReader) && d==iDocid; |
-} |
- |
-/* Return the first document in a document list. |
-*/ |
-static sqlite_int64 firstDocid(DocList *d){ |
- DocListReader r; |
- readerInit(&r, d); |
- return readDocid(&r); |
-} |
- |
-#ifdef SQLITE_DEBUG |
-/* |
-** This routine is used for debugging purpose only. |
-** |
-** Write the content of a doclist to standard output. |
-*/ |
-static void printDoclist(DocList *p){ |
- DocListReader r; |
- const char *zSep = ""; |
- |
- readerInit(&r, p); |
- while( !atEnd(&r) ){ |
- sqlite_int64 docid = readDocid(&r); |
- if( docid==0 ){ |
- skipPositionList(&r); |
- continue; |
- } |
- printf("%s%lld", zSep, docid); |
- zSep = ","; |
- if( p->iType>=DL_POSITIONS ){ |
- int iPos, iCol; |
- const char *zDiv = ""; |
- printf("("); |
- while( (iPos = readPosition(&r, &iCol))>=0 ){ |
- printf("%s%d:%d", zDiv, iCol, iPos); |
- zDiv = ":"; |
- } |
- printf(")"); |
- } |
- } |
- printf("\n"); |
- fflush(stdout); |
-} |
-#endif /* SQLITE_DEBUG */ |
- |
-/* Trim the given doclist to contain only positions in column |
- * [iRestrictColumn]. */ |
-static void docListRestrictColumn(DocList *in, int iRestrictColumn){ |
- DocListReader r; |
- DocList out; |
- |
- assert( in->iType>=DL_POSITIONS ); |
- readerInit(&r, in); |
- docListInit(&out, DL_POSITIONS, NULL, 0); |
- |
- while( !atEnd(&r) ){ |
- sqlite_int64 iDocid = readDocid(&r); |
- int iPos, iColumn; |
- |
- docListAddDocid(&out, iDocid); |
- while( (iPos = readPosition(&r, &iColumn)) != -1 ){ |
- if( iColumn==iRestrictColumn ){ |
- docListAddPos(&out, iColumn, iPos); |
- } |
- } |
- } |
- |
- docListDestroy(in); |
- *in = out; |
-} |
- |
-/* Trim the given doclist by discarding any docids without any remaining |
- * positions. */ |
-static void docListDiscardEmpty(DocList *in) { |
- DocListReader r; |
- DocList out; |
- |
- /* TODO: It would be nice to implement this operation in place; that |
- * could save a significant amount of memory in queries with long doclists. */ |
- assert( in->iType>=DL_POSITIONS ); |
- readerInit(&r, in); |
- docListInit(&out, DL_POSITIONS, NULL, 0); |
- |
- while( !atEnd(&r) ){ |
- sqlite_int64 iDocid = readDocid(&r); |
- int match = 0; |
- int iPos, iColumn; |
- while( (iPos = readPosition(&r, &iColumn)) != -1 ){ |
- if( !match ){ |
- docListAddDocid(&out, iDocid); |
- match = 1; |
- } |
- docListAddPos(&out, iColumn, iPos); |
- } |
- } |
- |
- docListDestroy(in); |
- *in = out; |
-} |
- |
-/* Helper function for docListUpdate() and docListAccumulate(). |
-** Splices a doclist element into the doclist represented by r, |
-** leaving r pointing after the newly spliced element. |
-*/ |
-static void docListSpliceElement(DocListReader *r, sqlite_int64 iDocid, |
- const char *pSource, int nSource){ |
- DocList *d = r->pDoclist; |
- char *pTarget; |
- int nTarget, found; |
- |
- found = skipToDocid(r, iDocid); |
- |
- /* Describe slice in d to place pSource/nSource. */ |
- pTarget = r->p; |
- if( found ){ |
- skipDocument(r); |
- nTarget = r->p-pTarget; |
- }else{ |
- nTarget = 0; |
- } |
- |
- /* The sense of the following is that there are three possibilities. |
- ** If nTarget==nSource, we should not move any memory nor realloc. |
- ** If nTarget>nSource, trim target and realloc. |
- ** If nTarget<nSource, realloc then expand target. |
- */ |
- if( nTarget>nSource ){ |
- memmove(pTarget+nSource, pTarget+nTarget, docListEnd(d)-(pTarget+nTarget)); |
- } |
- if( nTarget!=nSource ){ |
- int iDoclist = pTarget-d->pData; |
- d->pData = realloc(d->pData, d->nData+nSource-nTarget); |
- pTarget = d->pData+iDoclist; |
- } |
- if( nTarget<nSource ){ |
- memmove(pTarget+nSource, pTarget+nTarget, docListEnd(d)-(pTarget+nTarget)); |
- } |
- |
- memcpy(pTarget, pSource, nSource); |
- d->nData += nSource-nTarget; |
- r->p = pTarget+nSource; |
-} |
- |
-/* Insert/update pUpdate into the doclist. */ |
-static void docListUpdate(DocList *d, DocList *pUpdate){ |
- DocListReader reader; |
- |
- assert( d!=NULL && pUpdate!=NULL ); |
- assert( d->iType==pUpdate->iType); |
- |
- readerInit(&reader, d); |
- docListSpliceElement(&reader, firstDocid(pUpdate), |
- pUpdate->pData, pUpdate->nData); |
-} |
- |
-/* Propagate elements from pUpdate to pAcc, overwriting elements with |
-** matching docids. |
-*/ |
-static void docListAccumulate(DocList *pAcc, DocList *pUpdate){ |
- DocListReader accReader, updateReader; |
- |
- /* Handle edge cases where one doclist is empty. */ |
- assert( pAcc!=NULL ); |
- if( pUpdate==NULL || pUpdate->nData==0 ) return; |
- if( pAcc->nData==0 ){ |
- pAcc->pData = malloc(pUpdate->nData); |
- memcpy(pAcc->pData, pUpdate->pData, pUpdate->nData); |
- pAcc->nData = pUpdate->nData; |
- return; |
- } |
- |
- readerInit(&accReader, pAcc); |
- readerInit(&updateReader, pUpdate); |
- |
- while( !atEnd(&updateReader) ){ |
- char *pSource = updateReader.p; |
- sqlite_int64 iDocid = readDocid(&updateReader); |
- skipPositionList(&updateReader); |
- docListSpliceElement(&accReader, iDocid, pSource, updateReader.p-pSource); |
- } |
-} |
- |
-/* |
-** Read the next docid off of pIn. Return 0 if we reach the end. |
-* |
-* TODO: This assumes that docids are never 0, but they may actually be 0 since |
-* users can choose docids when inserting into a full-text table. Fix this. |
-*/ |
-static sqlite_int64 nextDocid(DocListReader *pIn){ |
- skipPositionList(pIn); |
- return atEnd(pIn) ? 0 : readDocid(pIn); |
-} |
- |
-/* |
-** pLeft and pRight are two DocListReaders that are pointing to |
-** positions lists of the same document: iDocid. |
-** |
-** If there are no instances in pLeft or pRight where the position |
-** of pLeft is one less than the position of pRight, then this |
-** routine adds nothing to pOut. |
-** |
-** If there are one or more instances where positions from pLeft |
-** are exactly one less than positions from pRight, then add a new |
-** document record to pOut. If pOut wants to hold positions, then |
-** include the positions from pRight that are one more than a |
-** position in pLeft. In other words: pRight.iPos==pLeft.iPos+1. |
-** |
-** pLeft and pRight are left pointing at the next document record. |
-*/ |
-static void mergePosList( |
- DocListReader *pLeft, /* Left position list */ |
- DocListReader *pRight, /* Right position list */ |
- sqlite_int64 iDocid, /* The docid from pLeft and pRight */ |
- DocList *pOut /* Write the merged document record here */ |
-){ |
- int iLeftCol, iLeftPos = readPosition(pLeft, &iLeftCol); |
- int iRightCol, iRightPos = readPosition(pRight, &iRightCol); |
- int match = 0; |
- |
- /* Loop until we've reached the end of both position lists. */ |
- while( iLeftPos!=-1 && iRightPos!=-1 ){ |
- if( iLeftCol==iRightCol && iLeftPos+1==iRightPos ){ |
- if( !match ){ |
- docListAddDocid(pOut, iDocid); |
- match = 1; |
- } |
- if( pOut->iType>=DL_POSITIONS ){ |
- docListAddPos(pOut, iRightCol, iRightPos); |
- } |
- iLeftPos = readPosition(pLeft, &iLeftCol); |
- iRightPos = readPosition(pRight, &iRightCol); |
- }else if( iRightCol<iLeftCol || |
- (iRightCol==iLeftCol && iRightPos<iLeftPos+1) ){ |
- iRightPos = readPosition(pRight, &iRightCol); |
- }else{ |
- iLeftPos = readPosition(pLeft, &iLeftCol); |
- } |
- } |
- if( iLeftPos>=0 ) skipPositionList(pLeft); |
- if( iRightPos>=0 ) skipPositionList(pRight); |
-} |
- |
-/* We have two doclists: pLeft and pRight. |
-** Write the phrase intersection of these two doclists into pOut. |
-** |
-** A phrase intersection means that two documents only match |
-** if pLeft.iPos+1==pRight.iPos. |
-** |
-** The output pOut may or may not contain positions. If pOut |
-** does contain positions, they are the positions of pRight. |
-*/ |
-static void docListPhraseMerge( |
- DocList *pLeft, /* Doclist resulting from the words on the left */ |
- DocList *pRight, /* Doclist for the next word to the right */ |
- DocList *pOut /* Write the combined doclist here */ |
-){ |
- DocListReader left, right; |
- sqlite_int64 docidLeft, docidRight; |
- |
- readerInit(&left, pLeft); |
- readerInit(&right, pRight); |
- docidLeft = nextDocid(&left); |
- docidRight = nextDocid(&right); |
- |
- while( docidLeft>0 && docidRight>0 ){ |
- if( docidLeft<docidRight ){ |
- docidLeft = nextDocid(&left); |
- }else if( docidRight<docidLeft ){ |
- docidRight = nextDocid(&right); |
- }else{ |
- mergePosList(&left, &right, docidLeft, pOut); |
- docidLeft = nextDocid(&left); |
- docidRight = nextDocid(&right); |
- } |
- } |
-} |
- |
-/* We have two doclists: pLeft and pRight. |
-** Write the intersection of these two doclists into pOut. |
-** Only docids are matched. Position information is ignored. |
-** |
-** The output pOut never holds positions. |
-*/ |
-static void docListAndMerge( |
- DocList *pLeft, /* Doclist resulting from the words on the left */ |
- DocList *pRight, /* Doclist for the next word to the right */ |
- DocList *pOut /* Write the combined doclist here */ |
-){ |
- DocListReader left, right; |
- sqlite_int64 docidLeft, docidRight; |
- |
- assert( pOut->iType<DL_POSITIONS ); |
- |
- readerInit(&left, pLeft); |
- readerInit(&right, pRight); |
- docidLeft = nextDocid(&left); |
- docidRight = nextDocid(&right); |
- |
- while( docidLeft>0 && docidRight>0 ){ |
- if( docidLeft<docidRight ){ |
- docidLeft = nextDocid(&left); |
- }else if( docidRight<docidLeft ){ |
- docidRight = nextDocid(&right); |
- }else{ |
- docListAddDocid(pOut, docidLeft); |
- docidLeft = nextDocid(&left); |
- docidRight = nextDocid(&right); |
- } |
- } |
-} |
- |
-/* We have two doclists: pLeft and pRight. |
-** Write the union of these two doclists into pOut. |
-** Only docids are matched. Position information is ignored. |
-** |
-** The output pOut never holds positions. |
-*/ |
-static void docListOrMerge( |
- DocList *pLeft, /* Doclist resulting from the words on the left */ |
- DocList *pRight, /* Doclist for the next word to the right */ |
- DocList *pOut /* Write the combined doclist here */ |
-){ |
- DocListReader left, right; |
- sqlite_int64 docidLeft, docidRight, priorLeft; |
- |
- readerInit(&left, pLeft); |
- readerInit(&right, pRight); |
- docidLeft = nextDocid(&left); |
- docidRight = nextDocid(&right); |
- |
- while( docidLeft>0 && docidRight>0 ){ |
- if( docidLeft<=docidRight ){ |
- docListAddDocid(pOut, docidLeft); |
- }else{ |
- docListAddDocid(pOut, docidRight); |
- } |
- priorLeft = docidLeft; |
- if( docidLeft<=docidRight ){ |
- docidLeft = nextDocid(&left); |
- } |
- if( docidRight>0 && docidRight<=priorLeft ){ |
- docidRight = nextDocid(&right); |
- } |
- } |
- while( docidLeft>0 ){ |
- docListAddDocid(pOut, docidLeft); |
- docidLeft = nextDocid(&left); |
- } |
- while( docidRight>0 ){ |
- docListAddDocid(pOut, docidRight); |
- docidRight = nextDocid(&right); |
- } |
-} |
- |
-/* We have two doclists: pLeft and pRight. |
-** Write into pOut all documents that occur in pLeft but not |
-** in pRight. |
-** |
-** Only docids are matched. Position information is ignored. |
-** |
-** The output pOut never holds positions. |
-*/ |
-static void docListExceptMerge( |
- DocList *pLeft, /* Doclist resulting from the words on the left */ |
- DocList *pRight, /* Doclist for the next word to the right */ |
- DocList *pOut /* Write the combined doclist here */ |
-){ |
- DocListReader left, right; |
- sqlite_int64 docidLeft, docidRight, priorLeft; |
- |
- readerInit(&left, pLeft); |
- readerInit(&right, pRight); |
- docidLeft = nextDocid(&left); |
- docidRight = nextDocid(&right); |
- |
- while( docidLeft>0 && docidRight>0 ){ |
- priorLeft = docidLeft; |
- if( docidLeft<docidRight ){ |
- docListAddDocid(pOut, docidLeft); |
- } |
- if( docidLeft<=docidRight ){ |
- docidLeft = nextDocid(&left); |
- } |
- if( docidRight>0 && docidRight<=priorLeft ){ |
- docidRight = nextDocid(&right); |
- } |
- } |
- while( docidLeft>0 ){ |
- docListAddDocid(pOut, docidLeft); |
- docidLeft = nextDocid(&left); |
- } |
-} |
- |
-static char *string_dup_n(const char *s, int n){ |
- char *str = malloc(n + 1); |
- memcpy(str, s, n); |
- str[n] = '\0'; |
- return str; |
-} |
- |
-/* Duplicate a string; the caller must free() the returned string. |
- * (We don't use strdup() since it is not part of the standard C library and |
- * may not be available everywhere.) */ |
-static char *string_dup(const char *s){ |
- return string_dup_n(s, strlen(s)); |
-} |
- |
-/* Format a string, replacing each occurrence of the % character with |
- * zDb.zName. This may be more convenient than sqlite_mprintf() |
- * when one string is used repeatedly in a format string. |
- * The caller must free() the returned string. */ |
-static char *string_format(const char *zFormat, |
- const char *zDb, const char *zName){ |
- const char *p; |
- size_t len = 0; |
- size_t nDb = strlen(zDb); |
- size_t nName = strlen(zName); |
- size_t nFullTableName = nDb+1+nName; |
- char *result; |
- char *r; |
- |
- /* first compute length needed */ |
- for(p = zFormat ; *p ; ++p){ |
- len += (*p=='%' ? nFullTableName : 1); |
- } |
- len += 1; /* for null terminator */ |
- |
- r = result = malloc(len); |
- for(p = zFormat; *p; ++p){ |
- if( *p=='%' ){ |
- memcpy(r, zDb, nDb); |
- r += nDb; |
- *r++ = '.'; |
- memcpy(r, zName, nName); |
- r += nName; |
- } else { |
- *r++ = *p; |
- } |
- } |
- *r++ = '\0'; |
- assert( r == result + len ); |
- return result; |
-} |
- |
-static int sql_exec(sqlite3 *db, const char *zDb, const char *zName, |
- const char *zFormat){ |
- char *zCommand = string_format(zFormat, zDb, zName); |
- int rc; |
- TRACE(("FTS1 sql: %s\n", zCommand)); |
- rc = sqlite3_exec(db, zCommand, NULL, 0, NULL); |
- free(zCommand); |
- return rc; |
-} |
- |
-static int sql_prepare(sqlite3 *db, const char *zDb, const char *zName, |
- sqlite3_stmt **ppStmt, const char *zFormat){ |
- char *zCommand = string_format(zFormat, zDb, zName); |
- int rc; |
- TRACE(("FTS1 prepare: %s\n", zCommand)); |
- rc = sqlite3_prepare(db, zCommand, -1, ppStmt, NULL); |
- free(zCommand); |
- return rc; |
-} |
- |
-/* end utility functions */ |
- |
-/* Forward reference */ |
-typedef struct fulltext_vtab fulltext_vtab; |
- |
-/* A single term in a query is represented by an instances of |
-** the following structure. |
-*/ |
-typedef struct QueryTerm { |
- short int nPhrase; /* How many following terms are part of the same phrase */ |
- short int iPhrase; /* This is the i-th term of a phrase. */ |
- short int iColumn; /* Column of the index that must match this term */ |
- signed char isOr; /* this term is preceded by "OR" */ |
- signed char isNot; /* this term is preceded by "-" */ |
- char *pTerm; /* text of the term. '\000' terminated. malloced */ |
- int nTerm; /* Number of bytes in pTerm[] */ |
-} QueryTerm; |
- |
- |
-/* A query string is parsed into a Query structure. |
- * |
- * We could, in theory, allow query strings to be complicated |
- * nested expressions with precedence determined by parentheses. |
- * But none of the major search engines do this. (Perhaps the |
- * feeling is that an parenthesized expression is two complex of |
- * an idea for the average user to grasp.) Taking our lead from |
- * the major search engines, we will allow queries to be a list |
- * of terms (with an implied AND operator) or phrases in double-quotes, |
- * with a single optional "-" before each non-phrase term to designate |
- * negation and an optional OR connector. |
- * |
- * OR binds more tightly than the implied AND, which is what the |
- * major search engines seem to do. So, for example: |
- * |
- * [one two OR three] ==> one AND (two OR three) |
- * [one OR two three] ==> (one OR two) AND three |
- * |
- * A "-" before a term matches all entries that lack that term. |
- * The "-" must occur immediately before the term with in intervening |
- * space. This is how the search engines do it. |
- * |
- * A NOT term cannot be the right-hand operand of an OR. If this |
- * occurs in the query string, the NOT is ignored: |
- * |
- * [one OR -two] ==> one OR two |
- * |
- */ |
-typedef struct Query { |
- fulltext_vtab *pFts; /* The full text index */ |
- int nTerms; /* Number of terms in the query */ |
- QueryTerm *pTerms; /* Array of terms. Space obtained from malloc() */ |
- int nextIsOr; /* Set the isOr flag on the next inserted term */ |
- int nextColumn; /* Next word parsed must be in this column */ |
- int dfltColumn; /* The default column */ |
-} Query; |
- |
- |
-/* |
-** An instance of the following structure keeps track of generated |
-** matching-word offset information and snippets. |
-*/ |
-typedef struct Snippet { |
- int nMatch; /* Total number of matches */ |
- int nAlloc; /* Space allocated for aMatch[] */ |
- struct snippetMatch { /* One entry for each matching term */ |
- char snStatus; /* Status flag for use while constructing snippets */ |
- short int iCol; /* The column that contains the match */ |
- short int iTerm; /* The index in Query.pTerms[] of the matching term */ |
- short int nByte; /* Number of bytes in the term */ |
- int iStart; /* The offset to the first character of the term */ |
- } *aMatch; /* Points to space obtained from malloc */ |
- char *zOffset; /* Text rendering of aMatch[] */ |
- int nOffset; /* strlen(zOffset) */ |
- char *zSnippet; /* Snippet text */ |
- int nSnippet; /* strlen(zSnippet) */ |
-} Snippet; |
- |
- |
-typedef enum QueryType { |
- QUERY_GENERIC, /* table scan */ |
- QUERY_ROWID, /* lookup by rowid */ |
- QUERY_FULLTEXT /* QUERY_FULLTEXT + [i] is a full-text search for column i*/ |
-} QueryType; |
- |
-/* TODO(shess) CHUNK_MAX controls how much data we allow in segment 0 |
-** before we start aggregating into larger segments. Lower CHUNK_MAX |
-** means that for a given input we have more individual segments per |
-** term, which means more rows in the table and a bigger index (due to |
-** both more rows and bigger rowids). But it also reduces the average |
-** cost of adding new elements to the segment 0 doclist, and it seems |
-** to reduce the number of pages read and written during inserts. 256 |
-** was chosen by measuring insertion times for a certain input (first |
-** 10k documents of Enron corpus), though including query performance |
-** in the decision may argue for a larger value. |
-*/ |
-#define CHUNK_MAX 256 |
- |
-typedef enum fulltext_statement { |
- CONTENT_INSERT_STMT, |
- CONTENT_SELECT_STMT, |
- CONTENT_UPDATE_STMT, |
- CONTENT_DELETE_STMT, |
- |
- TERM_SELECT_STMT, |
- TERM_SELECT_ALL_STMT, |
- TERM_INSERT_STMT, |
- TERM_UPDATE_STMT, |
- TERM_DELETE_STMT, |
- |
- MAX_STMT /* Always at end! */ |
-} fulltext_statement; |
- |
-/* These must exactly match the enum above. */ |
-/* TODO(adam): Is there some risk that a statement (in particular, |
-** pTermSelectStmt) will be used in two cursors at once, e.g. if a |
-** query joins a virtual table to itself? If so perhaps we should |
-** move some of these to the cursor object. |
-*/ |
-static const char *const fulltext_zStatement[MAX_STMT] = { |
- /* CONTENT_INSERT */ NULL, /* generated in contentInsertStatement() */ |
- /* CONTENT_SELECT */ "select * from %_content where rowid = ?", |
- /* CONTENT_UPDATE */ NULL, /* generated in contentUpdateStatement() */ |
- /* CONTENT_DELETE */ "delete from %_content where rowid = ?", |
- |
- /* TERM_SELECT */ |
- "select rowid, doclist from %_term where term = ? and segment = ?", |
- /* TERM_SELECT_ALL */ |
- "select doclist from %_term where term = ? order by segment", |
- /* TERM_INSERT */ |
- "insert into %_term (rowid, term, segment, doclist) values (?, ?, ?, ?)", |
- /* TERM_UPDATE */ "update %_term set doclist = ? where rowid = ?", |
- /* TERM_DELETE */ "delete from %_term where rowid = ?", |
-}; |
- |
-/* |
-** A connection to a fulltext index is an instance of the following |
-** structure. The xCreate and xConnect methods create an instance |
-** of this structure and xDestroy and xDisconnect free that instance. |
-** All other methods receive a pointer to the structure as one of their |
-** arguments. |
-*/ |
-struct fulltext_vtab { |
- sqlite3_vtab base; /* Base class used by SQLite core */ |
- sqlite3 *db; /* The database connection */ |
- const char *zDb; /* logical database name */ |
- const char *zName; /* virtual table name */ |
- int nColumn; /* number of columns in virtual table */ |
- char **azColumn; /* column names. malloced */ |
- char **azContentColumn; /* column names in content table; malloced */ |
- sqlite3_tokenizer *pTokenizer; /* tokenizer for inserts and queries */ |
- |
- /* Precompiled statements which we keep as long as the table is |
- ** open. |
- */ |
- sqlite3_stmt *pFulltextStatements[MAX_STMT]; |
-}; |
- |
-/* |
-** When the core wants to do a query, it create a cursor using a |
-** call to xOpen. This structure is an instance of a cursor. It |
-** is destroyed by xClose. |
-*/ |
-typedef struct fulltext_cursor { |
- sqlite3_vtab_cursor base; /* Base class used by SQLite core */ |
- QueryType iCursorType; /* Copy of sqlite3_index_info.idxNum */ |
- sqlite3_stmt *pStmt; /* Prepared statement in use by the cursor */ |
- int eof; /* True if at End Of Results */ |
- Query q; /* Parsed query string */ |
- Snippet snippet; /* Cached snippet for the current row */ |
- int iColumn; /* Column being searched */ |
- DocListReader result; /* used when iCursorType == QUERY_FULLTEXT */ |
-} fulltext_cursor; |
- |
-static struct fulltext_vtab *cursor_vtab(fulltext_cursor *c){ |
- return (fulltext_vtab *) c->base.pVtab; |
-} |
- |
-static const sqlite3_module fulltextModule; /* forward declaration */ |
- |
-/* Append a list of strings separated by commas to a StringBuffer. */ |
-static void appendList(StringBuffer *sb, int nString, char **azString){ |
- int i; |
- for(i=0; i<nString; ++i){ |
- if( i>0 ) append(sb, ", "); |
- append(sb, azString[i]); |
- } |
-} |
- |
-/* Return a dynamically generated statement of the form |
- * insert into %_content (rowid, ...) values (?, ...) |
- */ |
-static const char *contentInsertStatement(fulltext_vtab *v){ |
- StringBuffer sb; |
- int i; |
- |
- initStringBuffer(&sb); |
- append(&sb, "insert into %_content (rowid, "); |
- appendList(&sb, v->nColumn, v->azContentColumn); |
- append(&sb, ") values (?"); |
- for(i=0; i<v->nColumn; ++i) |
- append(&sb, ", ?"); |
- append(&sb, ")"); |
- return sb.s; |
-} |
- |
-/* Return a dynamically generated statement of the form |
- * update %_content set [col_0] = ?, [col_1] = ?, ... |
- * where rowid = ? |
- */ |
-static const char *contentUpdateStatement(fulltext_vtab *v){ |
- StringBuffer sb; |
- int i; |
- |
- initStringBuffer(&sb); |
- append(&sb, "update %_content set "); |
- for(i=0; i<v->nColumn; ++i) { |
- if( i>0 ){ |
- append(&sb, ", "); |
- } |
- append(&sb, v->azContentColumn[i]); |
- append(&sb, " = ?"); |
- } |
- append(&sb, " where rowid = ?"); |
- return sb.s; |
-} |
- |
-/* Puts a freshly-prepared statement determined by iStmt in *ppStmt. |
-** If the indicated statement has never been prepared, it is prepared |
-** and cached, otherwise the cached version is reset. |
-*/ |
-static int sql_get_statement(fulltext_vtab *v, fulltext_statement iStmt, |
- sqlite3_stmt **ppStmt){ |
- assert( iStmt<MAX_STMT ); |
- if( v->pFulltextStatements[iStmt]==NULL ){ |
- const char *zStmt; |
- int rc; |
- switch( iStmt ){ |
- case CONTENT_INSERT_STMT: |
- zStmt = contentInsertStatement(v); break; |
- case CONTENT_UPDATE_STMT: |
- zStmt = contentUpdateStatement(v); break; |
- default: |
- zStmt = fulltext_zStatement[iStmt]; |
- } |
- rc = sql_prepare(v->db, v->zDb, v->zName, &v->pFulltextStatements[iStmt], |
- zStmt); |
- if( zStmt != fulltext_zStatement[iStmt]) free((void *) zStmt); |
- if( rc!=SQLITE_OK ) return rc; |
- } else { |
- int rc = sqlite3_reset(v->pFulltextStatements[iStmt]); |
- if( rc!=SQLITE_OK ) return rc; |
- } |
- |
- *ppStmt = v->pFulltextStatements[iStmt]; |
- return SQLITE_OK; |
-} |
- |
-/* Step the indicated statement, handling errors SQLITE_BUSY (by |
-** retrying) and SQLITE_SCHEMA (by re-preparing and transferring |
-** bindings to the new statement). |
-** TODO(adam): We should extend this function so that it can work with |
-** statements declared locally, not only globally cached statements. |
-*/ |
-static int sql_step_statement(fulltext_vtab *v, fulltext_statement iStmt, |
- sqlite3_stmt **ppStmt){ |
- int rc; |
- sqlite3_stmt *s = *ppStmt; |
- assert( iStmt<MAX_STMT ); |
- assert( s==v->pFulltextStatements[iStmt] ); |
- |
- while( (rc=sqlite3_step(s))!=SQLITE_DONE && rc!=SQLITE_ROW ){ |
- if( rc==SQLITE_BUSY ) continue; |
- if( rc!=SQLITE_ERROR ) return rc; |
- |
- /* If an SQLITE_SCHEMA error has occurred, then finalizing this |
- * statement is going to delete the fulltext_vtab structure. If |
- * the statement just executed is in the pFulltextStatements[] |
- * array, it will be finalized twice. So remove it before |
- * calling sqlite3_finalize(). |
- */ |
- v->pFulltextStatements[iStmt] = NULL; |
- rc = sqlite3_finalize(s); |
- break; |
- } |
- return rc; |
- |
- err: |
- sqlite3_finalize(s); |
- return rc; |
-} |
- |
-/* Like sql_step_statement(), but convert SQLITE_DONE to SQLITE_OK. |
-** Useful for statements like UPDATE, where we expect no results. |
-*/ |
-static int sql_single_step_statement(fulltext_vtab *v, |
- fulltext_statement iStmt, |
- sqlite3_stmt **ppStmt){ |
- int rc = sql_step_statement(v, iStmt, ppStmt); |
- return (rc==SQLITE_DONE) ? SQLITE_OK : rc; |
-} |
- |
-/* insert into %_content (rowid, ...) values ([rowid], [pValues]) */ |
-static int content_insert(fulltext_vtab *v, sqlite3_value *rowid, |
- sqlite3_value **pValues){ |
- sqlite3_stmt *s; |
- int i; |
- int rc = sql_get_statement(v, CONTENT_INSERT_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_value(s, 1, rowid); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- for(i=0; i<v->nColumn; ++i){ |
- rc = sqlite3_bind_value(s, 2+i, pValues[i]); |
- if( rc!=SQLITE_OK ) return rc; |
- } |
- |
- return sql_single_step_statement(v, CONTENT_INSERT_STMT, &s); |
-} |
- |
-/* update %_content set col0 = pValues[0], col1 = pValues[1], ... |
- * where rowid = [iRowid] */ |
-static int content_update(fulltext_vtab *v, sqlite3_value **pValues, |
- sqlite_int64 iRowid){ |
- sqlite3_stmt *s; |
- int i; |
- int rc = sql_get_statement(v, CONTENT_UPDATE_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- for(i=0; i<v->nColumn; ++i){ |
- rc = sqlite3_bind_value(s, 1+i, pValues[i]); |
- if( rc!=SQLITE_OK ) return rc; |
- } |
- |
- rc = sqlite3_bind_int64(s, 1+v->nColumn, iRowid); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- return sql_single_step_statement(v, CONTENT_UPDATE_STMT, &s); |
-} |
- |
-static void freeStringArray(int nString, const char **pString){ |
- int i; |
- |
- for (i=0 ; i < nString ; ++i) { |
- if( pString[i]!=NULL ) free((void *) pString[i]); |
- } |
- free((void *) pString); |
-} |
- |
-/* select * from %_content where rowid = [iRow] |
- * The caller must delete the returned array and all strings in it. |
- * null fields will be NULL in the returned array. |
- * |
- * TODO: Perhaps we should return pointer/length strings here for consistency |
- * with other code which uses pointer/length. */ |
-static int content_select(fulltext_vtab *v, sqlite_int64 iRow, |
- const char ***pValues){ |
- sqlite3_stmt *s; |
- const char **values; |
- int i; |
- int rc; |
- |
- *pValues = NULL; |
- |
- rc = sql_get_statement(v, CONTENT_SELECT_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_int64(s, 1, iRow); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sql_step_statement(v, CONTENT_SELECT_STMT, &s); |
- if( rc!=SQLITE_ROW ) return rc; |
- |
- values = (const char **) malloc(v->nColumn * sizeof(const char *)); |
- for(i=0; i<v->nColumn; ++i){ |
- if( sqlite3_column_type(s, i)==SQLITE_NULL ){ |
- values[i] = NULL; |
- }else{ |
- values[i] = string_dup((char*)sqlite3_column_text(s, i)); |
- } |
- } |
- |
- /* We expect only one row. We must execute another sqlite3_step() |
- * to complete the iteration; otherwise the table will remain locked. */ |
- rc = sqlite3_step(s); |
- if( rc==SQLITE_DONE ){ |
- *pValues = values; |
- return SQLITE_OK; |
- } |
- |
- freeStringArray(v->nColumn, values); |
- return rc; |
-} |
- |
-/* delete from %_content where rowid = [iRow ] */ |
-static int content_delete(fulltext_vtab *v, sqlite_int64 iRow){ |
- sqlite3_stmt *s; |
- int rc = sql_get_statement(v, CONTENT_DELETE_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_int64(s, 1, iRow); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- return sql_single_step_statement(v, CONTENT_DELETE_STMT, &s); |
-} |
- |
-/* select rowid, doclist from %_term |
- * where term = [pTerm] and segment = [iSegment] |
- * If found, returns SQLITE_ROW; the caller must free the |
- * returned doclist. If no rows found, returns SQLITE_DONE. */ |
-static int term_select(fulltext_vtab *v, const char *pTerm, int nTerm, |
- int iSegment, |
- sqlite_int64 *rowid, DocList *out){ |
- sqlite3_stmt *s; |
- int rc = sql_get_statement(v, TERM_SELECT_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_text(s, 1, pTerm, nTerm, SQLITE_STATIC); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_int(s, 2, iSegment); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sql_step_statement(v, TERM_SELECT_STMT, &s); |
- if( rc!=SQLITE_ROW ) return rc; |
- |
- *rowid = sqlite3_column_int64(s, 0); |
- docListInit(out, DL_DEFAULT, |
- sqlite3_column_blob(s, 1), sqlite3_column_bytes(s, 1)); |
- |
- /* We expect only one row. We must execute another sqlite3_step() |
- * to complete the iteration; otherwise the table will remain locked. */ |
- rc = sqlite3_step(s); |
- return rc==SQLITE_DONE ? SQLITE_ROW : rc; |
-} |
- |
-/* Load the segment doclists for term pTerm and merge them in |
-** appropriate order into out. Returns SQLITE_OK if successful. If |
-** there are no segments for pTerm, successfully returns an empty |
-** doclist in out. |
-** |
-** Each document consists of 1 or more "columns". The number of |
-** columns is v->nColumn. If iColumn==v->nColumn, then return |
-** position information about all columns. If iColumn<v->nColumn, |
-** then only return position information about the iColumn-th column |
-** (where the first column is 0). |
-*/ |
-static int term_select_all( |
- fulltext_vtab *v, /* The fulltext index we are querying against */ |
- int iColumn, /* If <nColumn, only look at the iColumn-th column */ |
- const char *pTerm, /* The term whose posting lists we want */ |
- int nTerm, /* Number of bytes in pTerm */ |
- DocList *out /* Write the resulting doclist here */ |
-){ |
- DocList doclist; |
- sqlite3_stmt *s; |
- int rc = sql_get_statement(v, TERM_SELECT_ALL_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_text(s, 1, pTerm, nTerm, SQLITE_STATIC); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- docListInit(&doclist, DL_DEFAULT, 0, 0); |
- |
- /* TODO(shess) Handle schema and busy errors. */ |
- while( (rc=sql_step_statement(v, TERM_SELECT_ALL_STMT, &s))==SQLITE_ROW ){ |
- DocList old; |
- |
- /* TODO(shess) If we processed doclists from oldest to newest, we |
- ** could skip the malloc() involved with the following call. For |
- ** now, I'd rather keep this logic similar to index_insert_term(). |
- ** We could additionally drop elements when we see deletes, but |
- ** that would require a distinct version of docListAccumulate(). |
- */ |
- docListInit(&old, DL_DEFAULT, |
- sqlite3_column_blob(s, 0), sqlite3_column_bytes(s, 0)); |
- |
- if( iColumn<v->nColumn ){ /* querying a single column */ |
- docListRestrictColumn(&old, iColumn); |
- } |
- |
- /* doclist contains the newer data, so write it over old. Then |
- ** steal accumulated result for doclist. |
- */ |
- docListAccumulate(&old, &doclist); |
- docListDestroy(&doclist); |
- doclist = old; |
- } |
- if( rc!=SQLITE_DONE ){ |
- docListDestroy(&doclist); |
- return rc; |
- } |
- |
- docListDiscardEmpty(&doclist); |
- *out = doclist; |
- return SQLITE_OK; |
-} |
- |
-/* insert into %_term (rowid, term, segment, doclist) |
- values ([piRowid], [pTerm], [iSegment], [doclist]) |
-** Lets sqlite select rowid if piRowid is NULL, else uses *piRowid. |
-** |
-** NOTE(shess) piRowid is IN, with values of "space of int64" plus |
-** null, it is not used to pass data back to the caller. |
-*/ |
-static int term_insert(fulltext_vtab *v, sqlite_int64 *piRowid, |
- const char *pTerm, int nTerm, |
- int iSegment, DocList *doclist){ |
- sqlite3_stmt *s; |
- int rc = sql_get_statement(v, TERM_INSERT_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- if( piRowid==NULL ){ |
- rc = sqlite3_bind_null(s, 1); |
- }else{ |
- rc = sqlite3_bind_int64(s, 1, *piRowid); |
- } |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_text(s, 2, pTerm, nTerm, SQLITE_STATIC); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_int(s, 3, iSegment); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_blob(s, 4, doclist->pData, doclist->nData, SQLITE_STATIC); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- return sql_single_step_statement(v, TERM_INSERT_STMT, &s); |
-} |
- |
-/* update %_term set doclist = [doclist] where rowid = [rowid] */ |
-static int term_update(fulltext_vtab *v, sqlite_int64 rowid, |
- DocList *doclist){ |
- sqlite3_stmt *s; |
- int rc = sql_get_statement(v, TERM_UPDATE_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_blob(s, 1, doclist->pData, doclist->nData, SQLITE_STATIC); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_int64(s, 2, rowid); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- return sql_single_step_statement(v, TERM_UPDATE_STMT, &s); |
-} |
- |
-static int term_delete(fulltext_vtab *v, sqlite_int64 rowid){ |
- sqlite3_stmt *s; |
- int rc = sql_get_statement(v, TERM_DELETE_STMT, &s); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = sqlite3_bind_int64(s, 1, rowid); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- return sql_single_step_statement(v, TERM_DELETE_STMT, &s); |
-} |
- |
-/* |
-** Free the memory used to contain a fulltext_vtab structure. |
-*/ |
-static void fulltext_vtab_destroy(fulltext_vtab *v){ |
- int iStmt, i; |
- |
- TRACE(("FTS1 Destroy %p\n", v)); |
- for( iStmt=0; iStmt<MAX_STMT; iStmt++ ){ |
- if( v->pFulltextStatements[iStmt]!=NULL ){ |
- sqlite3_finalize(v->pFulltextStatements[iStmt]); |
- v->pFulltextStatements[iStmt] = NULL; |
- } |
- } |
- |
- if( v->pTokenizer!=NULL ){ |
- v->pTokenizer->pModule->xDestroy(v->pTokenizer); |
- v->pTokenizer = NULL; |
- } |
- |
- free(v->azColumn); |
- for(i = 0; i < v->nColumn; ++i) { |
- sqlite3_free(v->azContentColumn[i]); |
- } |
- free(v->azContentColumn); |
- free(v); |
-} |
- |
-/* |
-** Token types for parsing the arguments to xConnect or xCreate. |
-*/ |
-#define TOKEN_EOF 0 /* End of file */ |
-#define TOKEN_SPACE 1 /* Any kind of whitespace */ |
-#define TOKEN_ID 2 /* An identifier */ |
-#define TOKEN_STRING 3 /* A string literal */ |
-#define TOKEN_PUNCT 4 /* A single punctuation character */ |
- |
-/* |
-** If X is a character that can be used in an identifier then |
-** IdChar(X) will be true. Otherwise it is false. |
-** |
-** For ASCII, any character with the high-order bit set is |
-** allowed in an identifier. For 7-bit characters, |
-** sqlite3IsIdChar[X] must be 1. |
-** |
-** Ticket #1066. the SQL standard does not allow '$' in the |
-** middle of identfiers. But many SQL implementations do. |
-** SQLite will allow '$' in identifiers for compatibility. |
-** But the feature is undocumented. |
-*/ |
-static const char isIdChar[] = { |
-/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */ |
- 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 2x */ |
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 3x */ |
- 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 4x */ |
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, /* 5x */ |
- 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 6x */ |
- 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, /* 7x */ |
-}; |
-#define IdChar(C) (((c=C)&0x80)!=0 || (c>0x1f && isIdChar[c-0x20])) |
- |
- |
-/* |
-** Return the length of the token that begins at z[0]. |
-** Store the token type in *tokenType before returning. |
-*/ |
-static int getToken(const char *z, int *tokenType){ |
- int i, c; |
- switch( *z ){ |
- case 0: { |
- *tokenType = TOKEN_EOF; |
- return 0; |
- } |
- case ' ': case '\t': case '\n': case '\f': case '\r': { |
- for(i=1; safe_isspace(z[i]); i++){} |
- *tokenType = TOKEN_SPACE; |
- return i; |
- } |
- case '`': |
- case '\'': |
- case '"': { |
- int delim = z[0]; |
- for(i=1; (c=z[i])!=0; i++){ |
- if( c==delim ){ |
- if( z[i+1]==delim ){ |
- i++; |
- }else{ |
- break; |
- } |
- } |
- } |
- *tokenType = TOKEN_STRING; |
- return i + (c!=0); |
- } |
- case '[': { |
- for(i=1, c=z[0]; c!=']' && (c=z[i])!=0; i++){} |
- *tokenType = TOKEN_ID; |
- return i; |
- } |
- default: { |
- if( !IdChar(*z) ){ |
- break; |
- } |
- for(i=1; IdChar(z[i]); i++){} |
- *tokenType = TOKEN_ID; |
- return i; |
- } |
- } |
- *tokenType = TOKEN_PUNCT; |
- return 1; |
-} |
- |
-/* |
-** A token extracted from a string is an instance of the following |
-** structure. |
-*/ |
-typedef struct Token { |
- const char *z; /* Pointer to token text. Not '\000' terminated */ |
- short int n; /* Length of the token text in bytes. */ |
-} Token; |
- |
-/* |
-** Given a input string (which is really one of the argv[] parameters |
-** passed into xConnect or xCreate) split the string up into tokens. |
-** Return an array of pointers to '\000' terminated strings, one string |
-** for each non-whitespace token. |
-** |
-** The returned array is terminated by a single NULL pointer. |
-** |
-** Space to hold the returned array is obtained from a single |
-** malloc and should be freed by passing the return value to free(). |
-** The individual strings within the token list are all a part of |
-** the single memory allocation and will all be freed at once. |
-*/ |
-static char **tokenizeString(const char *z, int *pnToken){ |
- int nToken = 0; |
- Token *aToken = malloc( strlen(z) * sizeof(aToken[0]) ); |
- int n = 1; |
- int e, i; |
- int totalSize = 0; |
- char **azToken; |
- char *zCopy; |
- while( n>0 ){ |
- n = getToken(z, &e); |
- if( e!=TOKEN_SPACE ){ |
- aToken[nToken].z = z; |
- aToken[nToken].n = n; |
- nToken++; |
- totalSize += n+1; |
- } |
- z += n; |
- } |
- azToken = (char**)malloc( nToken*sizeof(char*) + totalSize ); |
- zCopy = (char*)&azToken[nToken]; |
- nToken--; |
- for(i=0; i<nToken; i++){ |
- azToken[i] = zCopy; |
- n = aToken[i].n; |
- memcpy(zCopy, aToken[i].z, n); |
- zCopy[n] = 0; |
- zCopy += n+1; |
- } |
- azToken[nToken] = 0; |
- free(aToken); |
- *pnToken = nToken; |
- return azToken; |
-} |
- |
-/* |
-** Convert an SQL-style quoted string into a normal string by removing |
-** the quote characters. The conversion is done in-place. If the |
-** input does not begin with a quote character, then this routine |
-** is a no-op. |
-** |
-** Examples: |
-** |
-** "abc" becomes abc |
-** 'xyz' becomes xyz |
-** [pqr] becomes pqr |
-** `mno` becomes mno |
-*/ |
-static void dequoteString(char *z){ |
- int quote; |
- int i, j; |
- if( z==0 ) return; |
- quote = z[0]; |
- switch( quote ){ |
- case '\'': break; |
- case '"': break; |
- case '`': break; /* For MySQL compatibility */ |
- case '[': quote = ']'; break; /* For MS SqlServer compatibility */ |
- default: return; |
- } |
- for(i=1, j=0; z[i]; i++){ |
- if( z[i]==quote ){ |
- if( z[i+1]==quote ){ |
- z[j++] = quote; |
- i++; |
- }else{ |
- z[j++] = 0; |
- break; |
- } |
- }else{ |
- z[j++] = z[i]; |
- } |
- } |
-} |
- |
-/* |
-** The input azIn is a NULL-terminated list of tokens. Remove the first |
-** token and all punctuation tokens. Remove the quotes from |
-** around string literal tokens. |
-** |
-** Example: |
-** |
-** input: tokenize chinese ( 'simplifed' , 'mixed' ) |
-** output: chinese simplifed mixed |
-** |
-** Another example: |
-** |
-** input: delimiters ( '[' , ']' , '...' ) |
-** output: [ ] ... |
-*/ |
-static void tokenListToIdList(char **azIn){ |
- int i, j; |
- if( azIn ){ |
- for(i=0, j=-1; azIn[i]; i++){ |
- if( safe_isalnum(azIn[i][0]) || azIn[i][1] ){ |
- dequoteString(azIn[i]); |
- if( j>=0 ){ |
- azIn[j] = azIn[i]; |
- } |
- j++; |
- } |
- } |
- azIn[j] = 0; |
- } |
-} |
- |
- |
-/* |
-** Find the first alphanumeric token in the string zIn. Null-terminate |
-** this token. Remove any quotation marks. And return a pointer to |
-** the result. |
-*/ |
-static char *firstToken(char *zIn, char **pzTail){ |
- int n, ttype; |
- while(1){ |
- n = getToken(zIn, &ttype); |
- if( ttype==TOKEN_SPACE ){ |
- zIn += n; |
- }else if( ttype==TOKEN_EOF ){ |
- *pzTail = zIn; |
- return 0; |
- }else{ |
- zIn[n] = 0; |
- *pzTail = &zIn[1]; |
- dequoteString(zIn); |
- return zIn; |
- } |
- } |
- /*NOTREACHED*/ |
-} |
- |
-/* Return true if... |
-** |
-** * s begins with the string t, ignoring case |
-** * s is longer than t |
-** * The first character of s beyond t is not a alphanumeric |
-** |
-** Ignore leading space in *s. |
-** |
-** To put it another way, return true if the first token of |
-** s[] is t[]. |
-*/ |
-static int startsWith(const char *s, const char *t){ |
- while( safe_isspace(*s) ){ s++; } |
- while( *t ){ |
- if( safe_tolower(*s++)!=safe_tolower(*t++) ) return 0; |
- } |
- return *s!='_' && !safe_isalnum(*s); |
-} |
- |
-/* |
-** An instance of this structure defines the "spec" of a |
-** full text index. This structure is populated by parseSpec |
-** and use by fulltextConnect and fulltextCreate. |
-*/ |
-typedef struct TableSpec { |
- const char *zDb; /* Logical database name */ |
- const char *zName; /* Name of the full-text index */ |
- int nColumn; /* Number of columns to be indexed */ |
- char **azColumn; /* Original names of columns to be indexed */ |
- char **azContentColumn; /* Column names for %_content */ |
- char **azTokenizer; /* Name of tokenizer and its arguments */ |
-} TableSpec; |
- |
-/* |
-** Reclaim all of the memory used by a TableSpec |
-*/ |
-static void clearTableSpec(TableSpec *p) { |
- free(p->azColumn); |
- free(p->azContentColumn); |
- free(p->azTokenizer); |
-} |
- |
-/* Parse a CREATE VIRTUAL TABLE statement, which looks like this: |
- * |
- * CREATE VIRTUAL TABLE email |
- * USING fts1(subject, body, tokenize mytokenizer(myarg)) |
- * |
- * We return parsed information in a TableSpec structure. |
- * |
- */ |
-static int parseSpec(TableSpec *pSpec, int argc, const char *const*argv, |
- char**pzErr){ |
- int i, n; |
- char *z, *zDummy; |
- char **azArg; |
- const char *zTokenizer = 0; /* argv[] entry describing the tokenizer */ |
- |
- assert( argc>=3 ); |
- /* Current interface: |
- ** argv[0] - module name |
- ** argv[1] - database name |
- ** argv[2] - table name |
- ** argv[3..] - columns, optionally followed by tokenizer specification |
- ** and snippet delimiters specification. |
- */ |
- |
- /* Make a copy of the complete argv[][] array in a single allocation. |
- ** The argv[][] array is read-only and transient. We can write to the |
- ** copy in order to modify things and the copy is persistent. |
- */ |
- memset(pSpec, 0, sizeof(*pSpec)); |
- for(i=n=0; i<argc; i++){ |
- n += strlen(argv[i]) + 1; |
- } |
- azArg = malloc( sizeof(char*)*argc + n ); |
- if( azArg==0 ){ |
- return SQLITE_NOMEM; |
- } |
- z = (char*)&azArg[argc]; |
- for(i=0; i<argc; i++){ |
- azArg[i] = z; |
- strcpy(z, argv[i]); |
- z += strlen(z)+1; |
- } |
- |
- /* Identify the column names and the tokenizer and delimiter arguments |
- ** in the argv[][] array. |
- */ |
- pSpec->zDb = azArg[1]; |
- pSpec->zName = azArg[2]; |
- pSpec->nColumn = 0; |
- pSpec->azColumn = azArg; |
- zTokenizer = "tokenize simple"; |
- for(i=3; i<argc; ++i){ |
- if( startsWith(azArg[i],"tokenize") ){ |
- zTokenizer = azArg[i]; |
- }else{ |
- z = azArg[pSpec->nColumn] = firstToken(azArg[i], &zDummy); |
- pSpec->nColumn++; |
- } |
- } |
- if( pSpec->nColumn==0 ){ |
- azArg[0] = "content"; |
- pSpec->nColumn = 1; |
- } |
- |
- /* |
- ** Construct the list of content column names. |
- ** |
- ** Each content column name will be of the form cNNAAAA |
- ** where NN is the column number and AAAA is the sanitized |
- ** column name. "sanitized" means that special characters are |
- ** converted to "_". The cNN prefix guarantees that all column |
- ** names are unique. |
- ** |
- ** The AAAA suffix is not strictly necessary. It is included |
- ** for the convenience of people who might examine the generated |
- ** %_content table and wonder what the columns are used for. |
- */ |
- pSpec->azContentColumn = malloc( pSpec->nColumn * sizeof(char *) ); |
- if( pSpec->azContentColumn==0 ){ |
- clearTableSpec(pSpec); |
- return SQLITE_NOMEM; |
- } |
- for(i=0; i<pSpec->nColumn; i++){ |
- char *p; |
- pSpec->azContentColumn[i] = sqlite3_mprintf("c%d%s", i, azArg[i]); |
- for (p = pSpec->azContentColumn[i]; *p ; ++p) { |
- if( !safe_isalnum(*p) ) *p = '_'; |
- } |
- } |
- |
- /* |
- ** Parse the tokenizer specification string. |
- */ |
- pSpec->azTokenizer = tokenizeString(zTokenizer, &n); |
- tokenListToIdList(pSpec->azTokenizer); |
- |
- return SQLITE_OK; |
-} |
- |
-/* |
-** Generate a CREATE TABLE statement that describes the schema of |
-** the virtual table. Return a pointer to this schema string. |
-** |
-** Space is obtained from sqlite3_mprintf() and should be freed |
-** using sqlite3_free(). |
-*/ |
-static char *fulltextSchema( |
- int nColumn, /* Number of columns */ |
- const char *const* azColumn, /* List of columns */ |
- const char *zTableName /* Name of the table */ |
-){ |
- int i; |
- char *zSchema, *zNext; |
- const char *zSep = "("; |
- zSchema = sqlite3_mprintf("CREATE TABLE x"); |
- for(i=0; i<nColumn; i++){ |
- zNext = sqlite3_mprintf("%s%s%Q", zSchema, zSep, azColumn[i]); |
- sqlite3_free(zSchema); |
- zSchema = zNext; |
- zSep = ","; |
- } |
- zNext = sqlite3_mprintf("%s,%Q)", zSchema, zTableName); |
- sqlite3_free(zSchema); |
- return zNext; |
-} |
- |
-/* |
-** Build a new sqlite3_vtab structure that will describe the |
-** fulltext index defined by spec. |
-*/ |
-static int constructVtab( |
- sqlite3 *db, /* The SQLite database connection */ |
- TableSpec *spec, /* Parsed spec information from parseSpec() */ |
- sqlite3_vtab **ppVTab, /* Write the resulting vtab structure here */ |
- char **pzErr /* Write any error message here */ |
-){ |
- int rc; |
- int n; |
- fulltext_vtab *v = 0; |
- const sqlite3_tokenizer_module *m = NULL; |
- char *schema; |
- |
- v = (fulltext_vtab *) malloc(sizeof(fulltext_vtab)); |
- if( v==0 ) return SQLITE_NOMEM; |
- memset(v, 0, sizeof(*v)); |
- /* sqlite will initialize v->base */ |
- v->db = db; |
- v->zDb = spec->zDb; /* Freed when azColumn is freed */ |
- v->zName = spec->zName; /* Freed when azColumn is freed */ |
- v->nColumn = spec->nColumn; |
- v->azContentColumn = spec->azContentColumn; |
- spec->azContentColumn = 0; |
- v->azColumn = spec->azColumn; |
- spec->azColumn = 0; |
- |
- if( spec->azTokenizer==0 ){ |
- return SQLITE_NOMEM; |
- } |
- /* TODO(shess) For now, add new tokenizers as else if clauses. */ |
- if( spec->azTokenizer[0]==0 || startsWith(spec->azTokenizer[0], "simple") ){ |
- sqlite3Fts1SimpleTokenizerModule(&m); |
- }else if( startsWith(spec->azTokenizer[0], "porter") ){ |
- sqlite3Fts1PorterTokenizerModule(&m); |
- }else{ |
- *pzErr = sqlite3_mprintf("unknown tokenizer: %s", spec->azTokenizer[0]); |
- rc = SQLITE_ERROR; |
- goto err; |
- } |
- for(n=0; spec->azTokenizer[n]; n++){} |
- if( n ){ |
- rc = m->xCreate(n-1, (const char*const*)&spec->azTokenizer[1], |
- &v->pTokenizer); |
- }else{ |
- rc = m->xCreate(0, 0, &v->pTokenizer); |
- } |
- if( rc!=SQLITE_OK ) goto err; |
- v->pTokenizer->pModule = m; |
- |
- /* TODO: verify the existence of backing tables foo_content, foo_term */ |
- |
- schema = fulltextSchema(v->nColumn, (const char*const*)v->azColumn, |
- spec->zName); |
- rc = sqlite3_declare_vtab(db, schema); |
- sqlite3_free(schema); |
- if( rc!=SQLITE_OK ) goto err; |
- |
- memset(v->pFulltextStatements, 0, sizeof(v->pFulltextStatements)); |
- |
- *ppVTab = &v->base; |
- TRACE(("FTS1 Connect %p\n", v)); |
- |
- return rc; |
- |
-err: |
- fulltext_vtab_destroy(v); |
- return rc; |
-} |
- |
-static int fulltextConnect( |
- sqlite3 *db, |
- void *pAux, |
- int argc, const char *const*argv, |
- sqlite3_vtab **ppVTab, |
- char **pzErr |
-){ |
- TableSpec spec; |
- int rc = parseSpec(&spec, argc, argv, pzErr); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = constructVtab(db, &spec, ppVTab, pzErr); |
- clearTableSpec(&spec); |
- return rc; |
-} |
- |
- /* The %_content table holds the text of each document, with |
- ** the rowid used as the docid. |
- ** |
- ** The %_term table maps each term to a document list blob |
- ** containing elements sorted by ascending docid, each element |
- ** encoded as: |
- ** |
- ** docid varint-encoded |
- ** token elements: |
- ** position+1 varint-encoded as delta from previous position |
- ** start offset varint-encoded as delta from previous start offset |
- ** end offset varint-encoded as delta from start offset |
- ** |
- ** The sentinel position of 0 indicates the end of the token list. |
- ** |
- ** Additionally, doclist blobs are chunked into multiple segments, |
- ** using segment to order the segments. New elements are added to |
- ** the segment at segment 0, until it exceeds CHUNK_MAX. Then |
- ** segment 0 is deleted, and the doclist is inserted at segment 1. |
- ** If there is already a doclist at segment 1, the segment 0 doclist |
- ** is merged with it, the segment 1 doclist is deleted, and the |
- ** merged doclist is inserted at segment 2, repeating those |
- ** operations until an insert succeeds. |
- ** |
- ** Since this structure doesn't allow us to update elements in place |
- ** in case of deletion or update, these are simply written to |
- ** segment 0 (with an empty token list in case of deletion), with |
- ** docListAccumulate() taking care to retain lower-segment |
- ** information in preference to higher-segment information. |
- */ |
- /* TODO(shess) Provide a VACUUM type operation which both removes |
- ** deleted elements which are no longer necessary, and duplicated |
- ** elements. I suspect this will probably not be necessary in |
- ** practice, though. |
- */ |
-static int fulltextCreate(sqlite3 *db, void *pAux, |
- int argc, const char * const *argv, |
- sqlite3_vtab **ppVTab, char **pzErr){ |
- int rc; |
- TableSpec spec; |
- StringBuffer schema; |
- TRACE(("FTS1 Create\n")); |
- |
- rc = parseSpec(&spec, argc, argv, pzErr); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- initStringBuffer(&schema); |
- append(&schema, "CREATE TABLE %_content("); |
- appendList(&schema, spec.nColumn, spec.azContentColumn); |
- append(&schema, ")"); |
- rc = sql_exec(db, spec.zDb, spec.zName, schema.s); |
- free(schema.s); |
- if( rc!=SQLITE_OK ) goto out; |
- |
- rc = sql_exec(db, spec.zDb, spec.zName, |
- "create table %_term(term text, segment integer, doclist blob, " |
- "primary key(term, segment));"); |
- if( rc!=SQLITE_OK ) goto out; |
- |
- rc = constructVtab(db, &spec, ppVTab, pzErr); |
- |
-out: |
- clearTableSpec(&spec); |
- return rc; |
-} |
- |
-/* Decide how to handle an SQL query. */ |
-static int fulltextBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){ |
- int i; |
- TRACE(("FTS1 BestIndex\n")); |
- |
- for(i=0; i<pInfo->nConstraint; ++i){ |
- const struct sqlite3_index_constraint *pConstraint; |
- pConstraint = &pInfo->aConstraint[i]; |
- if( pConstraint->usable ) { |
- if( pConstraint->iColumn==-1 && |
- pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){ |
- pInfo->idxNum = QUERY_ROWID; /* lookup by rowid */ |
- TRACE(("FTS1 QUERY_ROWID\n")); |
- } else if( pConstraint->iColumn>=0 && |
- pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH ){ |
- /* full-text search */ |
- pInfo->idxNum = QUERY_FULLTEXT + pConstraint->iColumn; |
- TRACE(("FTS1 QUERY_FULLTEXT %d\n", pConstraint->iColumn)); |
- } else continue; |
- |
- pInfo->aConstraintUsage[i].argvIndex = 1; |
- pInfo->aConstraintUsage[i].omit = 1; |
- |
- /* An arbitrary value for now. |
- * TODO: Perhaps rowid matches should be considered cheaper than |
- * full-text searches. */ |
- pInfo->estimatedCost = 1.0; |
- |
- return SQLITE_OK; |
- } |
- } |
- pInfo->idxNum = QUERY_GENERIC; |
- return SQLITE_OK; |
-} |
- |
-static int fulltextDisconnect(sqlite3_vtab *pVTab){ |
- TRACE(("FTS1 Disconnect %p\n", pVTab)); |
- fulltext_vtab_destroy((fulltext_vtab *)pVTab); |
- return SQLITE_OK; |
-} |
- |
-static int fulltextDestroy(sqlite3_vtab *pVTab){ |
- fulltext_vtab *v = (fulltext_vtab *)pVTab; |
- int rc; |
- |
- TRACE(("FTS1 Destroy %p\n", pVTab)); |
- rc = sql_exec(v->db, v->zDb, v->zName, |
- "drop table if exists %_content;" |
- "drop table if exists %_term;" |
- ); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- fulltext_vtab_destroy((fulltext_vtab *)pVTab); |
- return SQLITE_OK; |
-} |
- |
-static int fulltextOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){ |
- fulltext_cursor *c; |
- |
- c = (fulltext_cursor *) calloc(sizeof(fulltext_cursor), 1); |
- /* sqlite will initialize c->base */ |
- *ppCursor = &c->base; |
- TRACE(("FTS1 Open %p: %p\n", pVTab, c)); |
- |
- return SQLITE_OK; |
-} |
- |
- |
-/* Free all of the dynamically allocated memory held by *q |
-*/ |
-static void queryClear(Query *q){ |
- int i; |
- for(i = 0; i < q->nTerms; ++i){ |
- free(q->pTerms[i].pTerm); |
- } |
- free(q->pTerms); |
- memset(q, 0, sizeof(*q)); |
-} |
- |
-/* Free all of the dynamically allocated memory held by the |
-** Snippet |
-*/ |
-static void snippetClear(Snippet *p){ |
- free(p->aMatch); |
- free(p->zOffset); |
- free(p->zSnippet); |
- memset(p, 0, sizeof(*p)); |
-} |
-/* |
-** Append a single entry to the p->aMatch[] log. |
-*/ |
-static void snippetAppendMatch( |
- Snippet *p, /* Append the entry to this snippet */ |
- int iCol, int iTerm, /* The column and query term */ |
- int iStart, int nByte /* Offset and size of the match */ |
-){ |
- int i; |
- struct snippetMatch *pMatch; |
- if( p->nMatch+1>=p->nAlloc ){ |
- p->nAlloc = p->nAlloc*2 + 10; |
- p->aMatch = realloc(p->aMatch, p->nAlloc*sizeof(p->aMatch[0]) ); |
- if( p->aMatch==0 ){ |
- p->nMatch = 0; |
- p->nAlloc = 0; |
- return; |
- } |
- } |
- i = p->nMatch++; |
- pMatch = &p->aMatch[i]; |
- pMatch->iCol = iCol; |
- pMatch->iTerm = iTerm; |
- pMatch->iStart = iStart; |
- pMatch->nByte = nByte; |
-} |
- |
-/* |
-** Sizing information for the circular buffer used in snippetOffsetsOfColumn() |
-*/ |
-#define FTS1_ROTOR_SZ (32) |
-#define FTS1_ROTOR_MASK (FTS1_ROTOR_SZ-1) |
- |
-/* |
-** Add entries to pSnippet->aMatch[] for every match that occurs against |
-** document zDoc[0..nDoc-1] which is stored in column iColumn. |
-*/ |
-static void snippetOffsetsOfColumn( |
- Query *pQuery, |
- Snippet *pSnippet, |
- int iColumn, |
- const char *zDoc, |
- int nDoc |
-){ |
- const sqlite3_tokenizer_module *pTModule; /* The tokenizer module */ |
- sqlite3_tokenizer *pTokenizer; /* The specific tokenizer */ |
- sqlite3_tokenizer_cursor *pTCursor; /* Tokenizer cursor */ |
- fulltext_vtab *pVtab; /* The full text index */ |
- int nColumn; /* Number of columns in the index */ |
- const QueryTerm *aTerm; /* Query string terms */ |
- int nTerm; /* Number of query string terms */ |
- int i, j; /* Loop counters */ |
- int rc; /* Return code */ |
- unsigned int match, prevMatch; /* Phrase search bitmasks */ |
- const char *zToken; /* Next token from the tokenizer */ |
- int nToken; /* Size of zToken */ |
- int iBegin, iEnd, iPos; /* Offsets of beginning and end */ |
- |
- /* The following variables keep a circular buffer of the last |
- ** few tokens */ |
- unsigned int iRotor = 0; /* Index of current token */ |
- int iRotorBegin[FTS1_ROTOR_SZ]; /* Beginning offset of token */ |
- int iRotorLen[FTS1_ROTOR_SZ]; /* Length of token */ |
- |
- pVtab = pQuery->pFts; |
- nColumn = pVtab->nColumn; |
- pTokenizer = pVtab->pTokenizer; |
- pTModule = pTokenizer->pModule; |
- rc = pTModule->xOpen(pTokenizer, zDoc, nDoc, &pTCursor); |
- if( rc ) return; |
- pTCursor->pTokenizer = pTokenizer; |
- aTerm = pQuery->pTerms; |
- nTerm = pQuery->nTerms; |
- if( nTerm>=FTS1_ROTOR_SZ ){ |
- nTerm = FTS1_ROTOR_SZ - 1; |
- } |
- prevMatch = 0; |
- while(1){ |
- rc = pTModule->xNext(pTCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos); |
- if( rc ) break; |
- iRotorBegin[iRotor&FTS1_ROTOR_MASK] = iBegin; |
- iRotorLen[iRotor&FTS1_ROTOR_MASK] = iEnd-iBegin; |
- match = 0; |
- for(i=0; i<nTerm; i++){ |
- int iCol; |
- iCol = aTerm[i].iColumn; |
- if( iCol>=0 && iCol<nColumn && iCol!=iColumn ) continue; |
- if( aTerm[i].nTerm!=nToken ) continue; |
- if( memcmp(aTerm[i].pTerm, zToken, nToken) ) continue; |
- if( aTerm[i].iPhrase>1 && (prevMatch & (1<<i))==0 ) continue; |
- match |= 1<<i; |
- if( i==nTerm-1 || aTerm[i+1].iPhrase==1 ){ |
- for(j=aTerm[i].iPhrase-1; j>=0; j--){ |
- int k = (iRotor-j) & FTS1_ROTOR_MASK; |
- snippetAppendMatch(pSnippet, iColumn, i-j, |
- iRotorBegin[k], iRotorLen[k]); |
- } |
- } |
- } |
- prevMatch = match<<1; |
- iRotor++; |
- } |
- pTModule->xClose(pTCursor); |
-} |
- |
- |
-/* |
-** Compute all offsets for the current row of the query. |
-** If the offsets have already been computed, this routine is a no-op. |
-*/ |
-static void snippetAllOffsets(fulltext_cursor *p){ |
- int nColumn; |
- int iColumn, i; |
- int iFirst, iLast; |
- fulltext_vtab *pFts; |
- |
- if( p->snippet.nMatch ) return; |
- if( p->q.nTerms==0 ) return; |
- pFts = p->q.pFts; |
- nColumn = pFts->nColumn; |
- iColumn = p->iCursorType - QUERY_FULLTEXT; |
- if( iColumn<0 || iColumn>=nColumn ){ |
- iFirst = 0; |
- iLast = nColumn-1; |
- }else{ |
- iFirst = iColumn; |
- iLast = iColumn; |
- } |
- for(i=iFirst; i<=iLast; i++){ |
- const char *zDoc; |
- int nDoc; |
- zDoc = (const char*)sqlite3_column_text(p->pStmt, i+1); |
- nDoc = sqlite3_column_bytes(p->pStmt, i+1); |
- snippetOffsetsOfColumn(&p->q, &p->snippet, i, zDoc, nDoc); |
- } |
-} |
- |
-/* |
-** Convert the information in the aMatch[] array of the snippet |
-** into the string zOffset[0..nOffset-1]. |
-*/ |
-static void snippetOffsetText(Snippet *p){ |
- int i; |
- int cnt = 0; |
- StringBuffer sb; |
- char zBuf[200]; |
- if( p->zOffset ) return; |
- initStringBuffer(&sb); |
- for(i=0; i<p->nMatch; i++){ |
- struct snippetMatch *pMatch = &p->aMatch[i]; |
- zBuf[0] = ' '; |
- sqlite3_snprintf(sizeof(zBuf)-1, &zBuf[cnt>0], "%d %d %d %d", |
- pMatch->iCol, pMatch->iTerm, pMatch->iStart, pMatch->nByte); |
- append(&sb, zBuf); |
- cnt++; |
- } |
- p->zOffset = sb.s; |
- p->nOffset = sb.len; |
-} |
- |
-/* |
-** zDoc[0..nDoc-1] is phrase of text. aMatch[0..nMatch-1] are a set |
-** of matching words some of which might be in zDoc. zDoc is column |
-** number iCol. |
-** |
-** iBreak is suggested spot in zDoc where we could begin or end an |
-** excerpt. Return a value similar to iBreak but possibly adjusted |
-** to be a little left or right so that the break point is better. |
-*/ |
-static int wordBoundary( |
- int iBreak, /* The suggested break point */ |
- const char *zDoc, /* Document text */ |
- int nDoc, /* Number of bytes in zDoc[] */ |
- struct snippetMatch *aMatch, /* Matching words */ |
- int nMatch, /* Number of entries in aMatch[] */ |
- int iCol /* The column number for zDoc[] */ |
-){ |
- int i; |
- if( iBreak<=10 ){ |
- return 0; |
- } |
- if( iBreak>=nDoc-10 ){ |
- return nDoc; |
- } |
- for(i=0; i<nMatch && aMatch[i].iCol<iCol; i++){} |
- while( i<nMatch && aMatch[i].iStart+aMatch[i].nByte<iBreak ){ i++; } |
- if( i<nMatch ){ |
- if( aMatch[i].iStart<iBreak+10 ){ |
- return aMatch[i].iStart; |
- } |
- if( i>0 && aMatch[i-1].iStart+aMatch[i-1].nByte>=iBreak ){ |
- return aMatch[i-1].iStart; |
- } |
- } |
- for(i=1; i<=10; i++){ |
- if( safe_isspace(zDoc[iBreak-i]) ){ |
- return iBreak - i + 1; |
- } |
- if( safe_isspace(zDoc[iBreak+i]) ){ |
- return iBreak + i + 1; |
- } |
- } |
- return iBreak; |
-} |
- |
-/* |
-** If the StringBuffer does not end in white space, add a single |
-** space character to the end. |
-*/ |
-static void appendWhiteSpace(StringBuffer *p){ |
- if( p->len==0 ) return; |
- if( safe_isspace(p->s[p->len-1]) ) return; |
- append(p, " "); |
-} |
- |
-/* |
-** Remove white space from teh end of the StringBuffer |
-*/ |
-static void trimWhiteSpace(StringBuffer *p){ |
- while( p->len>0 && safe_isspace(p->s[p->len-1]) ){ |
- p->len--; |
- } |
-} |
- |
- |
- |
-/* |
-** Allowed values for Snippet.aMatch[].snStatus |
-*/ |
-#define SNIPPET_IGNORE 0 /* It is ok to omit this match from the snippet */ |
-#define SNIPPET_DESIRED 1 /* We want to include this match in the snippet */ |
- |
-/* |
-** Generate the text of a snippet. |
-*/ |
-static void snippetText( |
- fulltext_cursor *pCursor, /* The cursor we need the snippet for */ |
- const char *zStartMark, /* Markup to appear before each match */ |
- const char *zEndMark, /* Markup to appear after each match */ |
- const char *zEllipsis /* Ellipsis mark */ |
-){ |
- int i, j; |
- struct snippetMatch *aMatch; |
- int nMatch; |
- int nDesired; |
- StringBuffer sb; |
- int tailCol; |
- int tailOffset; |
- int iCol; |
- int nDoc; |
- const char *zDoc; |
- int iStart, iEnd; |
- int tailEllipsis = 0; |
- int iMatch; |
- |
- |
- free(pCursor->snippet.zSnippet); |
- pCursor->snippet.zSnippet = 0; |
- aMatch = pCursor->snippet.aMatch; |
- nMatch = pCursor->snippet.nMatch; |
- initStringBuffer(&sb); |
- |
- for(i=0; i<nMatch; i++){ |
- aMatch[i].snStatus = SNIPPET_IGNORE; |
- } |
- nDesired = 0; |
- for(i=0; i<pCursor->q.nTerms; i++){ |
- for(j=0; j<nMatch; j++){ |
- if( aMatch[j].iTerm==i ){ |
- aMatch[j].snStatus = SNIPPET_DESIRED; |
- nDesired++; |
- break; |
- } |
- } |
- } |
- |
- iMatch = 0; |
- tailCol = -1; |
- tailOffset = 0; |
- for(i=0; i<nMatch && nDesired>0; i++){ |
- if( aMatch[i].snStatus!=SNIPPET_DESIRED ) continue; |
- nDesired--; |
- iCol = aMatch[i].iCol; |
- zDoc = (const char*)sqlite3_column_text(pCursor->pStmt, iCol+1); |
- nDoc = sqlite3_column_bytes(pCursor->pStmt, iCol+1); |
- iStart = aMatch[i].iStart - 40; |
- iStart = wordBoundary(iStart, zDoc, nDoc, aMatch, nMatch, iCol); |
- if( iStart<=10 ){ |
- iStart = 0; |
- } |
- if( iCol==tailCol && iStart<=tailOffset+20 ){ |
- iStart = tailOffset; |
- } |
- if( (iCol!=tailCol && tailCol>=0) || iStart!=tailOffset ){ |
- trimWhiteSpace(&sb); |
- appendWhiteSpace(&sb); |
- append(&sb, zEllipsis); |
- appendWhiteSpace(&sb); |
- } |
- iEnd = aMatch[i].iStart + aMatch[i].nByte + 40; |
- iEnd = wordBoundary(iEnd, zDoc, nDoc, aMatch, nMatch, iCol); |
- if( iEnd>=nDoc-10 ){ |
- iEnd = nDoc; |
- tailEllipsis = 0; |
- }else{ |
- tailEllipsis = 1; |
- } |
- while( iMatch<nMatch && aMatch[iMatch].iCol<iCol ){ iMatch++; } |
- while( iStart<iEnd ){ |
- while( iMatch<nMatch && aMatch[iMatch].iStart<iStart |
- && aMatch[iMatch].iCol<=iCol ){ |
- iMatch++; |
- } |
- if( iMatch<nMatch && aMatch[iMatch].iStart<iEnd |
- && aMatch[iMatch].iCol==iCol ){ |
- nappend(&sb, &zDoc[iStart], aMatch[iMatch].iStart - iStart); |
- iStart = aMatch[iMatch].iStart; |
- append(&sb, zStartMark); |
- nappend(&sb, &zDoc[iStart], aMatch[iMatch].nByte); |
- append(&sb, zEndMark); |
- iStart += aMatch[iMatch].nByte; |
- for(j=iMatch+1; j<nMatch; j++){ |
- if( aMatch[j].iTerm==aMatch[iMatch].iTerm |
- && aMatch[j].snStatus==SNIPPET_DESIRED ){ |
- nDesired--; |
- aMatch[j].snStatus = SNIPPET_IGNORE; |
- } |
- } |
- }else{ |
- nappend(&sb, &zDoc[iStart], iEnd - iStart); |
- iStart = iEnd; |
- } |
- } |
- tailCol = iCol; |
- tailOffset = iEnd; |
- } |
- trimWhiteSpace(&sb); |
- if( tailEllipsis ){ |
- appendWhiteSpace(&sb); |
- append(&sb, zEllipsis); |
- } |
- pCursor->snippet.zSnippet = sb.s; |
- pCursor->snippet.nSnippet = sb.len; |
-} |
- |
- |
-/* |
-** Close the cursor. For additional information see the documentation |
-** on the xClose method of the virtual table interface. |
-*/ |
-static int fulltextClose(sqlite3_vtab_cursor *pCursor){ |
- fulltext_cursor *c = (fulltext_cursor *) pCursor; |
- TRACE(("FTS1 Close %p\n", c)); |
- sqlite3_finalize(c->pStmt); |
- queryClear(&c->q); |
- snippetClear(&c->snippet); |
- if( c->result.pDoclist!=NULL ){ |
- docListDelete(c->result.pDoclist); |
- } |
- free(c); |
- return SQLITE_OK; |
-} |
- |
-static int fulltextNext(sqlite3_vtab_cursor *pCursor){ |
- fulltext_cursor *c = (fulltext_cursor *) pCursor; |
- sqlite_int64 iDocid; |
- int rc; |
- |
- TRACE(("FTS1 Next %p\n", pCursor)); |
- snippetClear(&c->snippet); |
- if( c->iCursorType < QUERY_FULLTEXT ){ |
- /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */ |
- rc = sqlite3_step(c->pStmt); |
- switch( rc ){ |
- case SQLITE_ROW: |
- c->eof = 0; |
- return SQLITE_OK; |
- case SQLITE_DONE: |
- c->eof = 1; |
- return SQLITE_OK; |
- default: |
- c->eof = 1; |
- return rc; |
- } |
- } else { /* full-text query */ |
- rc = sqlite3_reset(c->pStmt); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- iDocid = nextDocid(&c->result); |
- if( iDocid==0 ){ |
- c->eof = 1; |
- return SQLITE_OK; |
- } |
- rc = sqlite3_bind_int64(c->pStmt, 1, iDocid); |
- if( rc!=SQLITE_OK ) return rc; |
- /* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */ |
- rc = sqlite3_step(c->pStmt); |
- if( rc==SQLITE_ROW ){ /* the case we expect */ |
- c->eof = 0; |
- return SQLITE_OK; |
- } |
- /* an error occurred; abort */ |
- return rc==SQLITE_DONE ? SQLITE_ERROR : rc; |
- } |
-} |
- |
- |
-/* Return a DocList corresponding to the query term *pTerm. If *pTerm |
-** is the first term of a phrase query, go ahead and evaluate the phrase |
-** query and return the doclist for the entire phrase query. |
-** |
-** The result is stored in pTerm->doclist. |
-*/ |
-static int docListOfTerm( |
- fulltext_vtab *v, /* The full text index */ |
- int iColumn, /* column to restrict to. No restrition if >=nColumn */ |
- QueryTerm *pQTerm, /* Term we are looking for, or 1st term of a phrase */ |
- DocList **ppResult /* Write the result here */ |
-){ |
- DocList *pLeft, *pRight, *pNew; |
- int i, rc; |
- |
- pLeft = docListNew(DL_POSITIONS); |
- rc = term_select_all(v, iColumn, pQTerm->pTerm, pQTerm->nTerm, pLeft); |
- if( rc ){ |
- docListDelete(pLeft); |
- return rc; |
- } |
- for(i=1; i<=pQTerm->nPhrase; i++){ |
- pRight = docListNew(DL_POSITIONS); |
- rc = term_select_all(v, iColumn, pQTerm[i].pTerm, pQTerm[i].nTerm, pRight); |
- if( rc ){ |
- docListDelete(pLeft); |
- return rc; |
- } |
- pNew = docListNew(i<pQTerm->nPhrase ? DL_POSITIONS : DL_DOCIDS); |
- docListPhraseMerge(pLeft, pRight, pNew); |
- docListDelete(pLeft); |
- docListDelete(pRight); |
- pLeft = pNew; |
- } |
- *ppResult = pLeft; |
- return SQLITE_OK; |
-} |
- |
-/* Add a new term pTerm[0..nTerm-1] to the query *q. |
-*/ |
-static void queryAdd(Query *q, const char *pTerm, int nTerm){ |
- QueryTerm *t; |
- ++q->nTerms; |
- q->pTerms = realloc(q->pTerms, q->nTerms * sizeof(q->pTerms[0])); |
- if( q->pTerms==0 ){ |
- q->nTerms = 0; |
- return; |
- } |
- t = &q->pTerms[q->nTerms - 1]; |
- memset(t, 0, sizeof(*t)); |
- t->pTerm = malloc(nTerm+1); |
- memcpy(t->pTerm, pTerm, nTerm); |
- t->pTerm[nTerm] = 0; |
- t->nTerm = nTerm; |
- t->isOr = q->nextIsOr; |
- q->nextIsOr = 0; |
- t->iColumn = q->nextColumn; |
- q->nextColumn = q->dfltColumn; |
-} |
- |
-/* |
-** Check to see if the string zToken[0...nToken-1] matches any |
-** column name in the virtual table. If it does, |
-** return the zero-indexed column number. If not, return -1. |
-*/ |
-static int checkColumnSpecifier( |
- fulltext_vtab *pVtab, /* The virtual table */ |
- const char *zToken, /* Text of the token */ |
- int nToken /* Number of characters in the token */ |
-){ |
- int i; |
- for(i=0; i<pVtab->nColumn; i++){ |
- if( memcmp(pVtab->azColumn[i], zToken, nToken)==0 |
- && pVtab->azColumn[i][nToken]==0 ){ |
- return i; |
- } |
- } |
- return -1; |
-} |
- |
-/* |
-** Parse the text at pSegment[0..nSegment-1]. Add additional terms |
-** to the query being assemblied in pQuery. |
-** |
-** inPhrase is true if pSegment[0..nSegement-1] is contained within |
-** double-quotes. If inPhrase is true, then the first term |
-** is marked with the number of terms in the phrase less one and |
-** OR and "-" syntax is ignored. If inPhrase is false, then every |
-** term found is marked with nPhrase=0 and OR and "-" syntax is significant. |
-*/ |
-static int tokenizeSegment( |
- sqlite3_tokenizer *pTokenizer, /* The tokenizer to use */ |
- const char *pSegment, int nSegment, /* Query expression being parsed */ |
- int inPhrase, /* True if within "..." */ |
- Query *pQuery /* Append results here */ |
-){ |
- const sqlite3_tokenizer_module *pModule = pTokenizer->pModule; |
- sqlite3_tokenizer_cursor *pCursor; |
- int firstIndex = pQuery->nTerms; |
- int iCol; |
- int nTerm = 1; |
- |
- int rc = pModule->xOpen(pTokenizer, pSegment, nSegment, &pCursor); |
- if( rc!=SQLITE_OK ) return rc; |
- pCursor->pTokenizer = pTokenizer; |
- |
- while( 1 ){ |
- const char *pToken; |
- int nToken, iBegin, iEnd, iPos; |
- |
- rc = pModule->xNext(pCursor, |
- &pToken, &nToken, |
- &iBegin, &iEnd, &iPos); |
- if( rc!=SQLITE_OK ) break; |
- if( !inPhrase && |
- pSegment[iEnd]==':' && |
- (iCol = checkColumnSpecifier(pQuery->pFts, pToken, nToken))>=0 ){ |
- pQuery->nextColumn = iCol; |
- continue; |
- } |
- if( !inPhrase && pQuery->nTerms>0 && nToken==2 |
- && pSegment[iBegin]=='O' && pSegment[iBegin+1]=='R' ){ |
- pQuery->nextIsOr = 1; |
- continue; |
- } |
- queryAdd(pQuery, pToken, nToken); |
- if( !inPhrase && iBegin>0 && pSegment[iBegin-1]=='-' ){ |
- pQuery->pTerms[pQuery->nTerms-1].isNot = 1; |
- } |
- pQuery->pTerms[pQuery->nTerms-1].iPhrase = nTerm; |
- if( inPhrase ){ |
- nTerm++; |
- } |
- } |
- |
- if( inPhrase && pQuery->nTerms>firstIndex ){ |
- pQuery->pTerms[firstIndex].nPhrase = pQuery->nTerms - firstIndex - 1; |
- } |
- |
- return pModule->xClose(pCursor); |
-} |
- |
-/* Parse a query string, yielding a Query object pQuery. |
-** |
-** The calling function will need to queryClear() to clean up |
-** the dynamically allocated memory held by pQuery. |
-*/ |
-static int parseQuery( |
- fulltext_vtab *v, /* The fulltext index */ |
- const char *zInput, /* Input text of the query string */ |
- int nInput, /* Size of the input text */ |
- int dfltColumn, /* Default column of the index to match against */ |
- Query *pQuery /* Write the parse results here. */ |
-){ |
- int iInput, inPhrase = 0; |
- |
- if( zInput==0 ) nInput = 0; |
- if( nInput<0 ) nInput = strlen(zInput); |
- pQuery->nTerms = 0; |
- pQuery->pTerms = NULL; |
- pQuery->nextIsOr = 0; |
- pQuery->nextColumn = dfltColumn; |
- pQuery->dfltColumn = dfltColumn; |
- pQuery->pFts = v; |
- |
- for(iInput=0; iInput<nInput; ++iInput){ |
- int i; |
- for(i=iInput; i<nInput && zInput[i]!='"'; ++i){} |
- if( i>iInput ){ |
- tokenizeSegment(v->pTokenizer, zInput+iInput, i-iInput, inPhrase, |
- pQuery); |
- } |
- iInput = i; |
- if( i<nInput ){ |
- assert( zInput[i]=='"' ); |
- inPhrase = !inPhrase; |
- } |
- } |
- |
- if( inPhrase ){ |
- /* unmatched quote */ |
- queryClear(pQuery); |
- return SQLITE_ERROR; |
- } |
- return SQLITE_OK; |
-} |
- |
-/* Perform a full-text query using the search expression in |
-** zInput[0..nInput-1]. Return a list of matching documents |
-** in pResult. |
-** |
-** Queries must match column iColumn. Or if iColumn>=nColumn |
-** they are allowed to match against any column. |
-*/ |
-static int fulltextQuery( |
- fulltext_vtab *v, /* The full text index */ |
- int iColumn, /* Match against this column by default */ |
- const char *zInput, /* The query string */ |
- int nInput, /* Number of bytes in zInput[] */ |
- DocList **pResult, /* Write the result doclist here */ |
- Query *pQuery /* Put parsed query string here */ |
-){ |
- int i, iNext, rc; |
- DocList *pLeft = NULL; |
- DocList *pRight, *pNew, *pOr; |
- int nNot = 0; |
- QueryTerm *aTerm; |
- |
- rc = parseQuery(v, zInput, nInput, iColumn, pQuery); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- /* Merge AND terms. */ |
- aTerm = pQuery->pTerms; |
- for(i = 0; i<pQuery->nTerms; i=iNext){ |
- if( aTerm[i].isNot ){ |
- /* Handle all NOT terms in a separate pass */ |
- nNot++; |
- iNext = i + aTerm[i].nPhrase+1; |
- continue; |
- } |
- iNext = i + aTerm[i].nPhrase + 1; |
- rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &pRight); |
- if( rc ){ |
- queryClear(pQuery); |
- return rc; |
- } |
- while( iNext<pQuery->nTerms && aTerm[iNext].isOr ){ |
- rc = docListOfTerm(v, aTerm[iNext].iColumn, &aTerm[iNext], &pOr); |
- iNext += aTerm[iNext].nPhrase + 1; |
- if( rc ){ |
- queryClear(pQuery); |
- return rc; |
- } |
- pNew = docListNew(DL_DOCIDS); |
- docListOrMerge(pRight, pOr, pNew); |
- docListDelete(pRight); |
- docListDelete(pOr); |
- pRight = pNew; |
- } |
- if( pLeft==0 ){ |
- pLeft = pRight; |
- }else{ |
- pNew = docListNew(DL_DOCIDS); |
- docListAndMerge(pLeft, pRight, pNew); |
- docListDelete(pRight); |
- docListDelete(pLeft); |
- pLeft = pNew; |
- } |
- } |
- |
- if( nNot && pLeft==0 ){ |
- /* We do not yet know how to handle a query of only NOT terms */ |
- return SQLITE_ERROR; |
- } |
- |
- /* Do the EXCEPT terms */ |
- for(i=0; i<pQuery->nTerms; i += aTerm[i].nPhrase + 1){ |
- if( !aTerm[i].isNot ) continue; |
- rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &pRight); |
- if( rc ){ |
- queryClear(pQuery); |
- docListDelete(pLeft); |
- return rc; |
- } |
- pNew = docListNew(DL_DOCIDS); |
- docListExceptMerge(pLeft, pRight, pNew); |
- docListDelete(pRight); |
- docListDelete(pLeft); |
- pLeft = pNew; |
- } |
- |
- *pResult = pLeft; |
- return rc; |
-} |
- |
-/* |
-** This is the xFilter interface for the virtual table. See |
-** the virtual table xFilter method documentation for additional |
-** information. |
-** |
-** If idxNum==QUERY_GENERIC then do a full table scan against |
-** the %_content table. |
-** |
-** If idxNum==QUERY_ROWID then do a rowid lookup for a single entry |
-** in the %_content table. |
-** |
-** If idxNum>=QUERY_FULLTEXT then use the full text index. The |
-** column on the left-hand side of the MATCH operator is column |
-** number idxNum-QUERY_FULLTEXT, 0 indexed. argv[0] is the right-hand |
-** side of the MATCH operator. |
-*/ |
-/* TODO(shess) Upgrade the cursor initialization and destruction to |
-** account for fulltextFilter() being called multiple times on the |
-** same cursor. The current solution is very fragile. Apply fix to |
-** fts2 as appropriate. |
-*/ |
-static int fulltextFilter( |
- sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */ |
- int idxNum, const char *idxStr, /* Which indexing scheme to use */ |
- int argc, sqlite3_value **argv /* Arguments for the indexing scheme */ |
-){ |
- fulltext_cursor *c = (fulltext_cursor *) pCursor; |
- fulltext_vtab *v = cursor_vtab(c); |
- int rc; |
- char *zSql; |
- |
- TRACE(("FTS1 Filter %p\n",pCursor)); |
- |
- zSql = sqlite3_mprintf("select rowid, * from %%_content %s", |
- idxNum==QUERY_GENERIC ? "" : "where rowid=?"); |
- sqlite3_finalize(c->pStmt); |
- rc = sql_prepare(v->db, v->zDb, v->zName, &c->pStmt, zSql); |
- sqlite3_free(zSql); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- c->iCursorType = idxNum; |
- switch( idxNum ){ |
- case QUERY_GENERIC: |
- break; |
- |
- case QUERY_ROWID: |
- rc = sqlite3_bind_int64(c->pStmt, 1, sqlite3_value_int64(argv[0])); |
- if( rc!=SQLITE_OK ) return rc; |
- break; |
- |
- default: /* full-text search */ |
- { |
- const char *zQuery = (const char *)sqlite3_value_text(argv[0]); |
- DocList *pResult; |
- assert( idxNum<=QUERY_FULLTEXT+v->nColumn); |
- assert( argc==1 ); |
- queryClear(&c->q); |
- rc = fulltextQuery(v, idxNum-QUERY_FULLTEXT, zQuery, -1, &pResult, &c->q); |
- if( rc!=SQLITE_OK ) return rc; |
- if( c->result.pDoclist!=NULL ) docListDelete(c->result.pDoclist); |
- readerInit(&c->result, pResult); |
- break; |
- } |
- } |
- |
- return fulltextNext(pCursor); |
-} |
- |
-/* This is the xEof method of the virtual table. The SQLite core |
-** calls this routine to find out if it has reached the end of |
-** a query's results set. |
-*/ |
-static int fulltextEof(sqlite3_vtab_cursor *pCursor){ |
- fulltext_cursor *c = (fulltext_cursor *) pCursor; |
- return c->eof; |
-} |
- |
-/* This is the xColumn method of the virtual table. The SQLite |
-** core calls this method during a query when it needs the value |
-** of a column from the virtual table. This method needs to use |
-** one of the sqlite3_result_*() routines to store the requested |
-** value back in the pContext. |
-*/ |
-static int fulltextColumn(sqlite3_vtab_cursor *pCursor, |
- sqlite3_context *pContext, int idxCol){ |
- fulltext_cursor *c = (fulltext_cursor *) pCursor; |
- fulltext_vtab *v = cursor_vtab(c); |
- |
- if( idxCol<v->nColumn ){ |
- sqlite3_value *pVal = sqlite3_column_value(c->pStmt, idxCol+1); |
- sqlite3_result_value(pContext, pVal); |
- }else if( idxCol==v->nColumn ){ |
- /* The extra column whose name is the same as the table. |
- ** Return a blob which is a pointer to the cursor |
- */ |
- sqlite3_result_blob(pContext, &c, sizeof(c), SQLITE_TRANSIENT); |
- } |
- return SQLITE_OK; |
-} |
- |
-/* This is the xRowid method. The SQLite core calls this routine to |
-** retrive the rowid for the current row of the result set. The |
-** rowid should be written to *pRowid. |
-*/ |
-static int fulltextRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){ |
- fulltext_cursor *c = (fulltext_cursor *) pCursor; |
- |
- *pRowid = sqlite3_column_int64(c->pStmt, 0); |
- return SQLITE_OK; |
-} |
- |
-/* Add all terms in [zText] to the given hash table. If [iColumn] > 0, |
- * we also store positions and offsets in the hash table using the given |
- * column number. */ |
-static int buildTerms(fulltext_vtab *v, fts1Hash *terms, sqlite_int64 iDocid, |
- const char *zText, int iColumn){ |
- sqlite3_tokenizer *pTokenizer = v->pTokenizer; |
- sqlite3_tokenizer_cursor *pCursor; |
- const char *pToken; |
- int nTokenBytes; |
- int iStartOffset, iEndOffset, iPosition; |
- int rc; |
- |
- rc = pTokenizer->pModule->xOpen(pTokenizer, zText, -1, &pCursor); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- pCursor->pTokenizer = pTokenizer; |
- while( SQLITE_OK==pTokenizer->pModule->xNext(pCursor, |
- &pToken, &nTokenBytes, |
- &iStartOffset, &iEndOffset, |
- &iPosition) ){ |
- DocList *p; |
- |
- /* Positions can't be negative; we use -1 as a terminator internally. */ |
- if( iPosition<0 ){ |
- pTokenizer->pModule->xClose(pCursor); |
- return SQLITE_ERROR; |
- } |
- |
- p = fts1HashFind(terms, pToken, nTokenBytes); |
- if( p==NULL ){ |
- p = docListNew(DL_DEFAULT); |
- docListAddDocid(p, iDocid); |
- fts1HashInsert(terms, pToken, nTokenBytes, p); |
- } |
- if( iColumn>=0 ){ |
- docListAddPosOffset(p, iColumn, iPosition, iStartOffset, iEndOffset); |
- } |
- } |
- |
- /* TODO(shess) Check return? Should this be able to cause errors at |
- ** this point? Actually, same question about sqlite3_finalize(), |
- ** though one could argue that failure there means that the data is |
- ** not durable. *ponder* |
- */ |
- pTokenizer->pModule->xClose(pCursor); |
- return rc; |
-} |
- |
-/* Update the %_terms table to map the term [pTerm] to the given rowid. */ |
-static int index_insert_term(fulltext_vtab *v, const char *pTerm, int nTerm, |
- DocList *d){ |
- sqlite_int64 iIndexRow; |
- DocList doclist; |
- int iSegment = 0, rc; |
- |
- rc = term_select(v, pTerm, nTerm, iSegment, &iIndexRow, &doclist); |
- if( rc==SQLITE_DONE ){ |
- docListInit(&doclist, DL_DEFAULT, 0, 0); |
- docListUpdate(&doclist, d); |
- /* TODO(shess) Consider length(doclist)>CHUNK_MAX? */ |
- rc = term_insert(v, NULL, pTerm, nTerm, iSegment, &doclist); |
- goto err; |
- } |
- if( rc!=SQLITE_ROW ) return SQLITE_ERROR; |
- |
- docListUpdate(&doclist, d); |
- if( doclist.nData<=CHUNK_MAX ){ |
- rc = term_update(v, iIndexRow, &doclist); |
- goto err; |
- } |
- |
- /* Doclist doesn't fit, delete what's there, and accumulate |
- ** forward. |
- */ |
- rc = term_delete(v, iIndexRow); |
- if( rc!=SQLITE_OK ) goto err; |
- |
- /* Try to insert the doclist into a higher segment bucket. On |
- ** failure, accumulate existing doclist with the doclist from that |
- ** bucket, and put results in the next bucket. |
- */ |
- iSegment++; |
- while( (rc=term_insert(v, &iIndexRow, pTerm, nTerm, iSegment, |
- &doclist))!=SQLITE_OK ){ |
- sqlite_int64 iSegmentRow; |
- DocList old; |
- int rc2; |
- |
- /* Retain old error in case the term_insert() error was really an |
- ** error rather than a bounced insert. |
- */ |
- rc2 = term_select(v, pTerm, nTerm, iSegment, &iSegmentRow, &old); |
- if( rc2!=SQLITE_ROW ) goto err; |
- |
- rc = term_delete(v, iSegmentRow); |
- if( rc!=SQLITE_OK ) goto err; |
- |
- /* Reusing lowest-number deleted row keeps the index smaller. */ |
- if( iSegmentRow<iIndexRow ) iIndexRow = iSegmentRow; |
- |
- /* doclist contains the newer data, so accumulate it over old. |
- ** Then steal accumulated data for doclist. |
- */ |
- docListAccumulate(&old, &doclist); |
- docListDestroy(&doclist); |
- doclist = old; |
- |
- iSegment++; |
- } |
- |
- err: |
- docListDestroy(&doclist); |
- return rc; |
-} |
- |
-/* Add doclists for all terms in [pValues] to the hash table [terms]. */ |
-static int insertTerms(fulltext_vtab *v, fts1Hash *terms, sqlite_int64 iRowid, |
- sqlite3_value **pValues){ |
- int i; |
- for(i = 0; i < v->nColumn ; ++i){ |
- char *zText = (char*)sqlite3_value_text(pValues[i]); |
- int rc = buildTerms(v, terms, iRowid, zText, i); |
- if( rc!=SQLITE_OK ) return rc; |
- } |
- return SQLITE_OK; |
-} |
- |
-/* Add empty doclists for all terms in the given row's content to the hash |
- * table [pTerms]. */ |
-static int deleteTerms(fulltext_vtab *v, fts1Hash *pTerms, sqlite_int64 iRowid){ |
- const char **pValues; |
- int i; |
- |
- int rc = content_select(v, iRowid, &pValues); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- for(i = 0 ; i < v->nColumn; ++i) { |
- rc = buildTerms(v, pTerms, iRowid, pValues[i], -1); |
- if( rc!=SQLITE_OK ) break; |
- } |
- |
- freeStringArray(v->nColumn, pValues); |
- return SQLITE_OK; |
-} |
- |
-/* Insert a row into the %_content table; set *piRowid to be the ID of the |
- * new row. Fill [pTerms] with new doclists for the %_term table. */ |
-static int index_insert(fulltext_vtab *v, sqlite3_value *pRequestRowid, |
- sqlite3_value **pValues, |
- sqlite_int64 *piRowid, fts1Hash *pTerms){ |
- int rc; |
- |
- rc = content_insert(v, pRequestRowid, pValues); /* execute an SQL INSERT */ |
- if( rc!=SQLITE_OK ) return rc; |
- *piRowid = sqlite3_last_insert_rowid(v->db); |
- return insertTerms(v, pTerms, *piRowid, pValues); |
-} |
- |
-/* Delete a row from the %_content table; fill [pTerms] with empty doclists |
- * to be written to the %_term table. */ |
-static int index_delete(fulltext_vtab *v, sqlite_int64 iRow, fts1Hash *pTerms){ |
- int rc = deleteTerms(v, pTerms, iRow); |
- if( rc!=SQLITE_OK ) return rc; |
- return content_delete(v, iRow); /* execute an SQL DELETE */ |
-} |
- |
-/* Update a row in the %_content table; fill [pTerms] with new doclists for the |
- * %_term table. */ |
-static int index_update(fulltext_vtab *v, sqlite_int64 iRow, |
- sqlite3_value **pValues, fts1Hash *pTerms){ |
- /* Generate an empty doclist for each term that previously appeared in this |
- * row. */ |
- int rc = deleteTerms(v, pTerms, iRow); |
- if( rc!=SQLITE_OK ) return rc; |
- |
- rc = content_update(v, pValues, iRow); /* execute an SQL UPDATE */ |
- if( rc!=SQLITE_OK ) return rc; |
- |
- /* Now add positions for terms which appear in the updated row. */ |
- return insertTerms(v, pTerms, iRow, pValues); |
-} |
- |
-/* This function implements the xUpdate callback; it is the top-level entry |
- * point for inserting, deleting or updating a row in a full-text table. */ |
-static int fulltextUpdate(sqlite3_vtab *pVtab, int nArg, sqlite3_value **ppArg, |
- sqlite_int64 *pRowid){ |
- fulltext_vtab *v = (fulltext_vtab *) pVtab; |
- fts1Hash terms; /* maps term string -> PosList */ |
- int rc; |
- fts1HashElem *e; |
- |
- TRACE(("FTS1 Update %p\n", pVtab)); |
- |
- fts1HashInit(&terms, FTS1_HASH_STRING, 1); |
- |
- if( nArg<2 ){ |
- rc = index_delete(v, sqlite3_value_int64(ppArg[0]), &terms); |
- } else if( sqlite3_value_type(ppArg[0]) != SQLITE_NULL ){ |
- /* An update: |
- * ppArg[0] = old rowid |
- * ppArg[1] = new rowid |
- * ppArg[2..2+v->nColumn-1] = values |
- * ppArg[2+v->nColumn] = value for magic column (we ignore this) |
- */ |
- sqlite_int64 rowid = sqlite3_value_int64(ppArg[0]); |
- if( sqlite3_value_type(ppArg[1]) != SQLITE_INTEGER || |
- sqlite3_value_int64(ppArg[1]) != rowid ){ |
- rc = SQLITE_ERROR; /* we don't allow changing the rowid */ |
- } else { |
- assert( nArg==2+v->nColumn+1); |
- rc = index_update(v, rowid, &ppArg[2], &terms); |
- } |
- } else { |
- /* An insert: |
- * ppArg[1] = requested rowid |
- * ppArg[2..2+v->nColumn-1] = values |
- * ppArg[2+v->nColumn] = value for magic column (we ignore this) |
- */ |
- assert( nArg==2+v->nColumn+1); |
- rc = index_insert(v, ppArg[1], &ppArg[2], pRowid, &terms); |
- } |
- |
- if( rc==SQLITE_OK ){ |
- /* Write updated doclists to disk. */ |
- for(e=fts1HashFirst(&terms); e; e=fts1HashNext(e)){ |
- DocList *p = fts1HashData(e); |
- rc = index_insert_term(v, fts1HashKey(e), fts1HashKeysize(e), p); |
- if( rc!=SQLITE_OK ) break; |
- } |
- } |
- |
- /* clean up */ |
- for(e=fts1HashFirst(&terms); e; e=fts1HashNext(e)){ |
- DocList *p = fts1HashData(e); |
- docListDelete(p); |
- } |
- fts1HashClear(&terms); |
- |
- return rc; |
-} |
- |
-/* |
-** Implementation of the snippet() function for FTS1 |
-*/ |
-static void snippetFunc( |
- sqlite3_context *pContext, |
- int argc, |
- sqlite3_value **argv |
-){ |
- fulltext_cursor *pCursor; |
- if( argc<1 ) return; |
- if( sqlite3_value_type(argv[0])!=SQLITE_BLOB || |
- sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){ |
- sqlite3_result_error(pContext, "illegal first argument to html_snippet",-1); |
- }else{ |
- const char *zStart = "<b>"; |
- const char *zEnd = "</b>"; |
- const char *zEllipsis = "<b>...</b>"; |
- memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor)); |
- if( argc>=2 ){ |
- zStart = (const char*)sqlite3_value_text(argv[1]); |
- if( argc>=3 ){ |
- zEnd = (const char*)sqlite3_value_text(argv[2]); |
- if( argc>=4 ){ |
- zEllipsis = (const char*)sqlite3_value_text(argv[3]); |
- } |
- } |
- } |
- snippetAllOffsets(pCursor); |
- snippetText(pCursor, zStart, zEnd, zEllipsis); |
- sqlite3_result_text(pContext, pCursor->snippet.zSnippet, |
- pCursor->snippet.nSnippet, SQLITE_STATIC); |
- } |
-} |
- |
-/* |
-** Implementation of the offsets() function for FTS1 |
-*/ |
-static void snippetOffsetsFunc( |
- sqlite3_context *pContext, |
- int argc, |
- sqlite3_value **argv |
-){ |
- fulltext_cursor *pCursor; |
- if( argc<1 ) return; |
- if( sqlite3_value_type(argv[0])!=SQLITE_BLOB || |
- sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){ |
- sqlite3_result_error(pContext, "illegal first argument to offsets",-1); |
- }else{ |
- memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor)); |
- snippetAllOffsets(pCursor); |
- snippetOffsetText(&pCursor->snippet); |
- sqlite3_result_text(pContext, |
- pCursor->snippet.zOffset, pCursor->snippet.nOffset, |
- SQLITE_STATIC); |
- } |
-} |
- |
-/* |
-** This routine implements the xFindFunction method for the FTS1 |
-** virtual table. |
-*/ |
-static int fulltextFindFunction( |
- sqlite3_vtab *pVtab, |
- int nArg, |
- const char *zName, |
- void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), |
- void **ppArg |
-){ |
- if( strcmp(zName,"snippet")==0 ){ |
- *pxFunc = snippetFunc; |
- return 1; |
- }else if( strcmp(zName,"offsets")==0 ){ |
- *pxFunc = snippetOffsetsFunc; |
- return 1; |
- } |
- return 0; |
-} |
- |
-/* |
-** Rename an fts1 table. |
-*/ |
-static int fulltextRename( |
- sqlite3_vtab *pVtab, |
- const char *zName |
-){ |
- fulltext_vtab *p = (fulltext_vtab *)pVtab; |
- int rc = SQLITE_NOMEM; |
- char *zSql = sqlite3_mprintf( |
- "ALTER TABLE %Q.'%q_content' RENAME TO '%q_content';" |
- "ALTER TABLE %Q.'%q_term' RENAME TO '%q_term';" |
- , p->zDb, p->zName, zName |
- , p->zDb, p->zName, zName |
- ); |
- if( zSql ){ |
- rc = sqlite3_exec(p->db, zSql, 0, 0, 0); |
- sqlite3_free(zSql); |
- } |
- return rc; |
-} |
- |
-static const sqlite3_module fulltextModule = { |
- /* iVersion */ 0, |
- /* xCreate */ fulltextCreate, |
- /* xConnect */ fulltextConnect, |
- /* xBestIndex */ fulltextBestIndex, |
- /* xDisconnect */ fulltextDisconnect, |
- /* xDestroy */ fulltextDestroy, |
- /* xOpen */ fulltextOpen, |
- /* xClose */ fulltextClose, |
- /* xFilter */ fulltextFilter, |
- /* xNext */ fulltextNext, |
- /* xEof */ fulltextEof, |
- /* xColumn */ fulltextColumn, |
- /* xRowid */ fulltextRowid, |
- /* xUpdate */ fulltextUpdate, |
- /* xBegin */ 0, |
- /* xSync */ 0, |
- /* xCommit */ 0, |
- /* xRollback */ 0, |
- /* xFindFunction */ fulltextFindFunction, |
- /* xRename */ fulltextRename, |
-}; |
- |
-int sqlite3Fts1Init(sqlite3 *db){ |
- sqlite3_overload_function(db, "snippet", -1); |
- sqlite3_overload_function(db, "offsets", -1); |
- return sqlite3_create_module(db, "fts1", &fulltextModule, 0); |
-} |
- |
-#if !SQLITE_CORE |
-#ifdef _WIN32 |
-__declspec(dllexport) |
-#endif |
-int sqlite3_fts1_init(sqlite3 *db, char **pzErrMsg, |
- const sqlite3_api_routines *pApi){ |
- SQLITE_EXTENSION_INIT2(pApi) |
- return sqlite3Fts1Init(db); |
-} |
-#endif |
- |
-#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS1) */ |