xref: /sqlite-3.40.0/ext/fts3/fts3Int.h (revision 38d69855)
1 /*
2 ** 2009 Nov 12
3 **
4 ** The author disclaims copyright to this source code.  In place of
5 ** a legal notice, here is a blessing:
6 **
7 **    May you do good and not evil.
8 **    May you find forgiveness for yourself and forgive others.
9 **    May you share freely, never taking more than you give.
10 **
11 ******************************************************************************
12 **
13 */
14 #ifndef _FTSINT_H
15 #define _FTSINT_H
16 
17 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
18 # define NDEBUG 1
19 #endif
20 
21 /* FTS3/FTS4 require virtual tables */
22 #ifdef SQLITE_OMIT_VIRTUALTABLE
23 # undef SQLITE_ENABLE_FTS3
24 # undef SQLITE_ENABLE_FTS4
25 #endif
26 
27 /*
28 ** FTS4 is really an extension for FTS3.  It is enabled using the
29 ** SQLITE_ENABLE_FTS3 macro.  But to avoid confusion we also all
30 ** the SQLITE_ENABLE_FTS4 macro to serve as an alisse for SQLITE_ENABLE_FTS3.
31 */
32 #if defined(SQLITE_ENABLE_FTS4) && !defined(SQLITE_ENABLE_FTS3)
33 # define SQLITE_ENABLE_FTS3
34 #endif
35 
36 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
37 
38 /* If not building as part of the core, include sqlite3ext.h. */
39 #ifndef SQLITE_CORE
40 # include "sqlite3ext.h"
41 SQLITE_EXTENSION_INIT3
42 #endif
43 
44 #include "sqlite3.h"
45 #include "fts3_tokenizer.h"
46 #include "fts3_hash.h"
47 
48 /*
49 ** This constant determines the maximum depth of an FTS expression tree
50 ** that the library will create and use. FTS uses recursion to perform
51 ** various operations on the query tree, so the disadvantage of a large
52 ** limit is that it may allow very large queries to use large amounts
53 ** of stack space (perhaps causing a stack overflow).
54 */
55 #ifndef SQLITE_FTS3_MAX_EXPR_DEPTH
56 # define SQLITE_FTS3_MAX_EXPR_DEPTH 12
57 #endif
58 
59 
60 /*
61 ** This constant controls how often segments are merged. Once there are
62 ** FTS3_MERGE_COUNT segments of level N, they are merged into a single
63 ** segment of level N+1.
64 */
65 #define FTS3_MERGE_COUNT 16
66 
67 /*
68 ** This is the maximum amount of data (in bytes) to store in the
69 ** Fts3Table.pendingTerms hash table. Normally, the hash table is
70 ** populated as documents are inserted/updated/deleted in a transaction
71 ** and used to create a new segment when the transaction is committed.
72 ** However if this limit is reached midway through a transaction, a new
73 ** segment is created and the hash table cleared immediately.
74 */
75 #define FTS3_MAX_PENDING_DATA (1*1024*1024)
76 
77 /*
78 ** Macro to return the number of elements in an array. SQLite has a
79 ** similar macro called ArraySize(). Use a different name to avoid
80 ** a collision when building an amalgamation with built-in FTS3.
81 */
82 #define SizeofArray(X) ((int)(sizeof(X)/sizeof(X[0])))
83 
84 
85 #ifndef MIN
86 # define MIN(x,y) ((x)<(y)?(x):(y))
87 #endif
88 #ifndef MAX
89 # define MAX(x,y) ((x)>(y)?(x):(y))
90 #endif
91 
92 /*
93 ** Maximum length of a varint encoded integer. The varint format is different
94 ** from that used by SQLite, so the maximum length is 10, not 9.
95 */
96 #define FTS3_VARINT_MAX 10
97 
98 /*
99 ** FTS4 virtual tables may maintain multiple indexes - one index of all terms
100 ** in the document set and zero or more prefix indexes. All indexes are stored
101 ** as one or more b+-trees in the %_segments and %_segdir tables.
102 **
103 ** It is possible to determine which index a b+-tree belongs to based on the
104 ** value stored in the "%_segdir.level" column. Given this value L, the index
105 ** that the b+-tree belongs to is (L<<10). In other words, all b+-trees with
106 ** level values between 0 and 1023 (inclusive) belong to index 0, all levels
107 ** between 1024 and 2047 to index 1, and so on.
108 **
109 ** It is considered impossible for an index to use more than 1024 levels. In
110 ** theory though this may happen, but only after at least
111 ** (FTS3_MERGE_COUNT^1024) separate flushes of the pending-terms tables.
112 */
113 #define FTS3_SEGDIR_MAXLEVEL      1024
114 #define FTS3_SEGDIR_MAXLEVEL_STR "1024"
115 
116 /*
117 ** The testcase() macro is only used by the amalgamation.  If undefined,
118 ** make it a no-op.
119 */
120 #ifndef testcase
121 # define testcase(X)
122 #endif
123 
124 /*
125 ** Terminator values for position-lists and column-lists.
126 */
127 #define POS_COLUMN  (1)     /* Column-list terminator */
128 #define POS_END     (0)     /* Position-list terminator */
129 
130 /*
131 ** This section provides definitions to allow the
132 ** FTS3 extension to be compiled outside of the
133 ** amalgamation.
134 */
135 #ifndef SQLITE_AMALGAMATION
136 /*
137 ** Macros indicating that conditional expressions are always true or
138 ** false.
139 */
140 #ifdef SQLITE_COVERAGE_TEST
141 # define ALWAYS(x) (1)
142 # define NEVER(X)  (0)
143 #elif defined(SQLITE_DEBUG)
144 # define ALWAYS(x) sqlite3Fts3Always((x)!=0)
145 # define NEVER(x) sqlite3Fts3Never((x)!=0)
146 int sqlite3Fts3Always(int b);
147 int sqlite3Fts3Never(int b);
148 #else
149 # define ALWAYS(x) (x)
150 # define NEVER(x)  (x)
151 #endif
152 
153 /*
154 ** Internal types used by SQLite.
155 */
156 typedef unsigned char u8;         /* 1-byte (or larger) unsigned integer */
157 typedef short int i16;            /* 2-byte (or larger) signed integer */
158 typedef unsigned int u32;         /* 4-byte unsigned integer */
159 typedef sqlite3_uint64 u64;       /* 8-byte unsigned integer */
160 typedef sqlite3_int64 i64;        /* 8-byte signed integer */
161 
162 /*
163 ** Macro used to suppress compiler warnings for unused parameters.
164 */
165 #define UNUSED_PARAMETER(x) (void)(x)
166 
167 /*
168 ** Activate assert() only if SQLITE_TEST is enabled.
169 */
170 #if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
171 # define NDEBUG 1
172 #endif
173 
174 /*
175 ** The TESTONLY macro is used to enclose variable declarations or
176 ** other bits of code that are needed to support the arguments
177 ** within testcase() and assert() macros.
178 */
179 #if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
180 # define TESTONLY(X)  X
181 #else
182 # define TESTONLY(X)
183 #endif
184 
185 #endif /* SQLITE_AMALGAMATION */
186 
187 #ifdef SQLITE_DEBUG
188 int sqlite3Fts3Corrupt(void);
189 # define FTS_CORRUPT_VTAB sqlite3Fts3Corrupt()
190 #else
191 # define FTS_CORRUPT_VTAB SQLITE_CORRUPT_VTAB
192 #endif
193 
194 typedef struct Fts3Table Fts3Table;
195 typedef struct Fts3Cursor Fts3Cursor;
196 typedef struct Fts3Expr Fts3Expr;
197 typedef struct Fts3Phrase Fts3Phrase;
198 typedef struct Fts3PhraseToken Fts3PhraseToken;
199 
200 typedef struct Fts3Doclist Fts3Doclist;
201 typedef struct Fts3SegFilter Fts3SegFilter;
202 typedef struct Fts3DeferredToken Fts3DeferredToken;
203 typedef struct Fts3SegReader Fts3SegReader;
204 typedef struct Fts3MultiSegReader Fts3MultiSegReader;
205 
206 typedef struct MatchinfoBuffer MatchinfoBuffer;
207 
208 /*
209 ** A connection to a fulltext index is an instance of the following
210 ** structure. The xCreate and xConnect methods create an instance
211 ** of this structure and xDestroy and xDisconnect free that instance.
212 ** All other methods receive a pointer to the structure as one of their
213 ** arguments.
214 */
215 struct Fts3Table {
216   sqlite3_vtab base;              /* Base class used by SQLite core */
217   sqlite3 *db;                    /* The database connection */
218   const char *zDb;                /* logical database name */
219   const char *zName;              /* virtual table name */
220   int nColumn;                    /* number of named columns in virtual table */
221   char **azColumn;                /* column names.  malloced */
222   u8 *abNotindexed;               /* True for 'notindexed' columns */
223   sqlite3_tokenizer *pTokenizer;  /* tokenizer for inserts and queries */
224   char *zContentTbl;              /* content=xxx option, or NULL */
225   char *zLanguageid;              /* languageid=xxx option, or NULL */
226   int nAutoincrmerge;             /* Value configured by 'automerge' */
227   u32 nLeafAdd;                   /* Number of leaf blocks added this trans */
228 
229   /* Precompiled statements used by the implementation. Each of these
230   ** statements is run and reset within a single virtual table API call.
231   */
232   sqlite3_stmt *aStmt[40];
233 
234   char *zReadExprlist;
235   char *zWriteExprlist;
236 
237   int nNodeSize;                  /* Soft limit for node size */
238   u8 bFts4;                       /* True for FTS4, false for FTS3 */
239   u8 bHasStat;                    /* True if %_stat table exists (2==unknown) */
240   u8 bHasDocsize;                 /* True if %_docsize table exists */
241   u8 bDescIdx;                    /* True if doclists are in reverse order */
242   u8 bIgnoreSavepoint;            /* True to ignore xSavepoint invocations */
243   int nPgsz;                      /* Page size for host database */
244   char *zSegmentsTbl;             /* Name of %_segments table */
245   sqlite3_blob *pSegments;        /* Blob handle open on %_segments table */
246 
247   /*
248   ** The following array of hash tables is used to buffer pending index
249   ** updates during transactions. All pending updates buffered at any one
250   ** time must share a common language-id (see the FTS4 langid= feature).
251   ** The current language id is stored in variable iPrevLangid.
252   **
253   ** A single FTS4 table may have multiple full-text indexes. For each index
254   ** there is an entry in the aIndex[] array. Index 0 is an index of all the
255   ** terms that appear in the document set. Each subsequent index in aIndex[]
256   ** is an index of prefixes of a specific length.
257   **
258   ** Variable nPendingData contains an estimate the memory consumed by the
259   ** pending data structures, including hash table overhead, but not including
260   ** malloc overhead.  When nPendingData exceeds nMaxPendingData, all hash
261   ** tables are flushed to disk. Variable iPrevDocid is the docid of the most
262   ** recently inserted record.
263   */
264   int nIndex;                     /* Size of aIndex[] */
265   struct Fts3Index {
266     int nPrefix;                  /* Prefix length (0 for main terms index) */
267     Fts3Hash hPending;            /* Pending terms table for this index */
268   } *aIndex;
269   int nMaxPendingData;            /* Max pending data before flush to disk */
270   int nPendingData;               /* Current bytes of pending data */
271   sqlite_int64 iPrevDocid;        /* Docid of most recently inserted document */
272   int iPrevLangid;                /* Langid of recently inserted document */
273   int bPrevDelete;                /* True if last operation was a delete */
274 
275 #if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
276   /* State variables used for validating that the transaction control
277   ** methods of the virtual table are called at appropriate times.  These
278   ** values do not contribute to FTS functionality; they are used for
279   ** verifying the operation of the SQLite core.
280   */
281   int inTransaction;     /* True after xBegin but before xCommit/xRollback */
282   int mxSavepoint;       /* Largest valid xSavepoint integer */
283 #endif
284 
285 #ifdef SQLITE_TEST
286   /* True to disable the incremental doclist optimization. This is controled
287   ** by special insert command 'test-no-incr-doclist'.  */
288   int bNoIncrDoclist;
289 #endif
290 };
291 
292 /*
293 ** When the core wants to read from the virtual table, it creates a
294 ** virtual table cursor (an instance of the following structure) using
295 ** the xOpen method. Cursors are destroyed using the xClose method.
296 */
297 struct Fts3Cursor {
298   sqlite3_vtab_cursor base;       /* Base class used by SQLite core */
299   i16 eSearch;                    /* Search strategy (see below) */
300   u8 isEof;                       /* True if at End Of Results */
301   u8 isRequireSeek;               /* True if must seek pStmt to %_content row */
302   sqlite3_stmt *pStmt;            /* Prepared statement in use by the cursor */
303   Fts3Expr *pExpr;                /* Parsed MATCH query string */
304   int iLangid;                    /* Language being queried for */
305   int nPhrase;                    /* Number of matchable phrases in query */
306   Fts3DeferredToken *pDeferred;   /* Deferred search tokens, if any */
307   sqlite3_int64 iPrevId;          /* Previous id read from aDoclist */
308   char *pNextId;                  /* Pointer into the body of aDoclist */
309   char *aDoclist;                 /* List of docids for full-text queries */
310   int nDoclist;                   /* Size of buffer at aDoclist */
311   u8 bDesc;                       /* True to sort in descending order */
312   int eEvalmode;                  /* An FTS3_EVAL_XX constant */
313   int nRowAvg;                    /* Average size of database rows, in pages */
314   sqlite3_int64 nDoc;             /* Documents in table */
315   i64 iMinDocid;                  /* Minimum docid to return */
316   i64 iMaxDocid;                  /* Maximum docid to return */
317   int isMatchinfoNeeded;          /* True when aMatchinfo[] needs filling in */
318   MatchinfoBuffer *pMIBuffer;     /* Buffer for matchinfo data */
319 };
320 
321 #define FTS3_EVAL_FILTER    0
322 #define FTS3_EVAL_NEXT      1
323 #define FTS3_EVAL_MATCHINFO 2
324 
325 /*
326 ** The Fts3Cursor.eSearch member is always set to one of the following.
327 ** Actualy, Fts3Cursor.eSearch can be greater than or equal to
328 ** FTS3_FULLTEXT_SEARCH.  If so, then Fts3Cursor.eSearch - 2 is the index
329 ** of the column to be searched.  For example, in
330 **
331 **     CREATE VIRTUAL TABLE ex1 USING fts3(a,b,c,d);
332 **     SELECT docid FROM ex1 WHERE b MATCH 'one two three';
333 **
334 ** Because the LHS of the MATCH operator is 2nd column "b",
335 ** Fts3Cursor.eSearch will be set to FTS3_FULLTEXT_SEARCH+1.  (+0 for a,
336 ** +1 for b, +2 for c, +3 for d.)  If the LHS of MATCH were "ex1"
337 ** indicating that all columns should be searched,
338 ** then eSearch would be set to FTS3_FULLTEXT_SEARCH+4.
339 */
340 #define FTS3_FULLSCAN_SEARCH 0    /* Linear scan of %_content table */
341 #define FTS3_DOCID_SEARCH    1    /* Lookup by rowid on %_content table */
342 #define FTS3_FULLTEXT_SEARCH 2    /* Full-text index search */
343 
344 /*
345 ** The lower 16-bits of the sqlite3_index_info.idxNum value set by
346 ** the xBestIndex() method contains the Fts3Cursor.eSearch value described
347 ** above. The upper 16-bits contain a combination of the following
348 ** bits, used to describe extra constraints on full-text searches.
349 */
350 #define FTS3_HAVE_LANGID    0x00010000      /* languageid=? */
351 #define FTS3_HAVE_DOCID_GE  0x00020000      /* docid>=? */
352 #define FTS3_HAVE_DOCID_LE  0x00040000      /* docid<=? */
353 
354 struct Fts3Doclist {
355   char *aAll;                    /* Array containing doclist (or NULL) */
356   int nAll;                      /* Size of a[] in bytes */
357   char *pNextDocid;              /* Pointer to next docid */
358 
359   sqlite3_int64 iDocid;          /* Current docid (if pList!=0) */
360   int bFreeList;                 /* True if pList should be sqlite3_free()d */
361   char *pList;                   /* Pointer to position list following iDocid */
362   int nList;                     /* Length of position list */
363 };
364 
365 /*
366 ** A "phrase" is a sequence of one or more tokens that must match in
367 ** sequence.  A single token is the base case and the most common case.
368 ** For a sequence of tokens contained in double-quotes (i.e. "one two three")
369 ** nToken will be the number of tokens in the string.
370 */
371 struct Fts3PhraseToken {
372   char *z;                        /* Text of the token */
373   int n;                          /* Number of bytes in buffer z */
374   int isPrefix;                   /* True if token ends with a "*" character */
375   int bFirst;                     /* True if token must appear at position 0 */
376 
377   /* Variables above this point are populated when the expression is
378   ** parsed (by code in fts3_expr.c). Below this point the variables are
379   ** used when evaluating the expression. */
380   Fts3DeferredToken *pDeferred;   /* Deferred token object for this token */
381   Fts3MultiSegReader *pSegcsr;    /* Segment-reader for this token */
382 };
383 
384 struct Fts3Phrase {
385   /* Cache of doclist for this phrase. */
386   Fts3Doclist doclist;
387   int bIncr;                 /* True if doclist is loaded incrementally */
388   int iDoclistToken;
389 
390   /* Used by sqlite3Fts3EvalPhrasePoslist() if this is a descendent of an
391   ** OR condition.  */
392   char *pOrPoslist;
393   i64 iOrDocid;
394 
395   /* Variables below this point are populated by fts3_expr.c when parsing
396   ** a MATCH expression. Everything above is part of the evaluation phase.
397   */
398   int nToken;                /* Number of tokens in the phrase */
399   int iColumn;               /* Index of column this phrase must match */
400   Fts3PhraseToken aToken[1]; /* One entry for each token in the phrase */
401 };
402 
403 /*
404 ** A tree of these objects forms the RHS of a MATCH operator.
405 **
406 ** If Fts3Expr.eType is FTSQUERY_PHRASE and isLoaded is true, then aDoclist
407 ** points to a malloced buffer, size nDoclist bytes, containing the results
408 ** of this phrase query in FTS3 doclist format. As usual, the initial
409 ** "Length" field found in doclists stored on disk is omitted from this
410 ** buffer.
411 **
412 ** Variable aMI is used only for FTSQUERY_NEAR nodes to store the global
413 ** matchinfo data. If it is not NULL, it points to an array of size nCol*3,
414 ** where nCol is the number of columns in the queried FTS table. The array
415 ** is populated as follows:
416 **
417 **   aMI[iCol*3 + 0] = Undefined
418 **   aMI[iCol*3 + 1] = Number of occurrences
419 **   aMI[iCol*3 + 2] = Number of rows containing at least one instance
420 **
421 ** The aMI array is allocated using sqlite3_malloc(). It should be freed
422 ** when the expression node is.
423 */
424 struct Fts3Expr {
425   int eType;                 /* One of the FTSQUERY_XXX values defined below */
426   int nNear;                 /* Valid if eType==FTSQUERY_NEAR */
427   Fts3Expr *pParent;         /* pParent->pLeft==this or pParent->pRight==this */
428   Fts3Expr *pLeft;           /* Left operand */
429   Fts3Expr *pRight;          /* Right operand */
430   Fts3Phrase *pPhrase;       /* Valid if eType==FTSQUERY_PHRASE */
431 
432   /* The following are used by the fts3_eval.c module. */
433   sqlite3_int64 iDocid;      /* Current docid */
434   u8 bEof;                   /* True this expression is at EOF already */
435   u8 bStart;                 /* True if iDocid is valid */
436   u8 bDeferred;              /* True if this expression is entirely deferred */
437 
438   /* The following are used by the fts3_snippet.c module. */
439   int iPhrase;               /* Index of this phrase in matchinfo() results */
440   u32 *aMI;                  /* See above */
441 };
442 
443 /*
444 ** Candidate values for Fts3Query.eType. Note that the order of the first
445 ** four values is in order of precedence when parsing expressions. For
446 ** example, the following:
447 **
448 **   "a OR b AND c NOT d NEAR e"
449 **
450 ** is equivalent to:
451 **
452 **   "a OR (b AND (c NOT (d NEAR e)))"
453 */
454 #define FTSQUERY_NEAR   1
455 #define FTSQUERY_NOT    2
456 #define FTSQUERY_AND    3
457 #define FTSQUERY_OR     4
458 #define FTSQUERY_PHRASE 5
459 
460 
461 /* fts3_write.c */
462 int sqlite3Fts3UpdateMethod(sqlite3_vtab*,int,sqlite3_value**,sqlite3_int64*);
463 int sqlite3Fts3PendingTermsFlush(Fts3Table *);
464 void sqlite3Fts3PendingTermsClear(Fts3Table *);
465 int sqlite3Fts3Optimize(Fts3Table *);
466 int sqlite3Fts3SegReaderNew(int, int, sqlite3_int64,
467   sqlite3_int64, sqlite3_int64, const char *, int, Fts3SegReader**);
468 int sqlite3Fts3SegReaderPending(
469   Fts3Table*,int,const char*,int,int,Fts3SegReader**);
470 void sqlite3Fts3SegReaderFree(Fts3SegReader *);
471 int sqlite3Fts3AllSegdirs(Fts3Table*, int, int, int, sqlite3_stmt **);
472 int sqlite3Fts3ReadBlock(Fts3Table*, sqlite3_int64, char **, int*, int*);
473 
474 int sqlite3Fts3SelectDoctotal(Fts3Table *, sqlite3_stmt **);
475 int sqlite3Fts3SelectDocsize(Fts3Table *, sqlite3_int64, sqlite3_stmt **);
476 
477 #ifndef SQLITE_DISABLE_FTS4_DEFERRED
478 void sqlite3Fts3FreeDeferredTokens(Fts3Cursor *);
479 int sqlite3Fts3DeferToken(Fts3Cursor *, Fts3PhraseToken *, int);
480 int sqlite3Fts3CacheDeferredDoclists(Fts3Cursor *);
481 void sqlite3Fts3FreeDeferredDoclists(Fts3Cursor *);
482 int sqlite3Fts3DeferredTokenList(Fts3DeferredToken *, char **, int *);
483 #else
484 # define sqlite3Fts3FreeDeferredTokens(x)
485 # define sqlite3Fts3DeferToken(x,y,z) SQLITE_OK
486 # define sqlite3Fts3CacheDeferredDoclists(x) SQLITE_OK
487 # define sqlite3Fts3FreeDeferredDoclists(x)
488 # define sqlite3Fts3DeferredTokenList(x,y,z) SQLITE_OK
489 #endif
490 
491 void sqlite3Fts3SegmentsClose(Fts3Table *);
492 int sqlite3Fts3MaxLevel(Fts3Table *, int *);
493 
494 /* Special values interpreted by sqlite3SegReaderCursor() */
495 #define FTS3_SEGCURSOR_PENDING        -1
496 #define FTS3_SEGCURSOR_ALL            -2
497 
498 int sqlite3Fts3SegReaderStart(Fts3Table*, Fts3MultiSegReader*, Fts3SegFilter*);
499 int sqlite3Fts3SegReaderStep(Fts3Table *, Fts3MultiSegReader *);
500 void sqlite3Fts3SegReaderFinish(Fts3MultiSegReader *);
501 
502 int sqlite3Fts3SegReaderCursor(Fts3Table *,
503     int, int, int, const char *, int, int, int, Fts3MultiSegReader *);
504 
505 /* Flags allowed as part of the 4th argument to SegmentReaderIterate() */
506 #define FTS3_SEGMENT_REQUIRE_POS   0x00000001
507 #define FTS3_SEGMENT_IGNORE_EMPTY  0x00000002
508 #define FTS3_SEGMENT_COLUMN_FILTER 0x00000004
509 #define FTS3_SEGMENT_PREFIX        0x00000008
510 #define FTS3_SEGMENT_SCAN          0x00000010
511 #define FTS3_SEGMENT_FIRST         0x00000020
512 
513 /* Type passed as 4th argument to SegmentReaderIterate() */
514 struct Fts3SegFilter {
515   const char *zTerm;
516   int nTerm;
517   int iCol;
518   int flags;
519 };
520 
521 struct Fts3MultiSegReader {
522   /* Used internally by sqlite3Fts3SegReaderXXX() calls */
523   Fts3SegReader **apSegment;      /* Array of Fts3SegReader objects */
524   int nSegment;                   /* Size of apSegment array */
525   int nAdvance;                   /* How many seg-readers to advance */
526   Fts3SegFilter *pFilter;         /* Pointer to filter object */
527   char *aBuffer;                  /* Buffer to merge doclists in */
528   int nBuffer;                    /* Allocated size of aBuffer[] in bytes */
529 
530   int iColFilter;                 /* If >=0, filter for this column */
531   int bRestart;
532 
533   /* Used by fts3.c only. */
534   int nCost;                      /* Cost of running iterator */
535   int bLookup;                    /* True if a lookup of a single entry. */
536 
537   /* Output values. Valid only after Fts3SegReaderStep() returns SQLITE_ROW. */
538   char *zTerm;                    /* Pointer to term buffer */
539   int nTerm;                      /* Size of zTerm in bytes */
540   char *aDoclist;                 /* Pointer to doclist buffer */
541   int nDoclist;                   /* Size of aDoclist[] in bytes */
542 };
543 
544 int sqlite3Fts3Incrmerge(Fts3Table*,int,int);
545 
546 #define fts3GetVarint32(p, piVal) (                                           \
547   (*(u8*)(p)&0x80) ? sqlite3Fts3GetVarint32(p, piVal) : (*piVal=*(u8*)(p), 1) \
548 )
549 
550 /* fts3.c */
551 void sqlite3Fts3ErrMsg(char**,const char*,...);
552 int sqlite3Fts3PutVarint(char *, sqlite3_int64);
553 int sqlite3Fts3GetVarint(const char *, sqlite_int64 *);
554 int sqlite3Fts3GetVarint32(const char *, int *);
555 int sqlite3Fts3VarintLen(sqlite3_uint64);
556 void sqlite3Fts3Dequote(char *);
557 void sqlite3Fts3DoclistPrev(int,char*,int,char**,sqlite3_int64*,int*,u8*);
558 int sqlite3Fts3EvalPhraseStats(Fts3Cursor *, Fts3Expr *, u32 *);
559 int sqlite3Fts3FirstFilter(sqlite3_int64, char *, int, char *);
560 void sqlite3Fts3CreateStatTable(int*, Fts3Table*);
561 int sqlite3Fts3EvalTestDeferred(Fts3Cursor *pCsr, int *pRc);
562 
563 /* fts3_tokenizer.c */
564 const char *sqlite3Fts3NextToken(const char *, int *);
565 int sqlite3Fts3InitHashTable(sqlite3 *, Fts3Hash *, const char *);
566 int sqlite3Fts3InitTokenizer(Fts3Hash *pHash, const char *,
567     sqlite3_tokenizer **, char **
568 );
569 int sqlite3Fts3IsIdChar(char);
570 
571 /* fts3_snippet.c */
572 void sqlite3Fts3Offsets(sqlite3_context*, Fts3Cursor*);
573 void sqlite3Fts3Snippet(sqlite3_context *, Fts3Cursor *, const char *,
574   const char *, const char *, int, int
575 );
576 void sqlite3Fts3Matchinfo(sqlite3_context *, Fts3Cursor *, const char *);
577 void sqlite3Fts3MIBufferFree(MatchinfoBuffer *p);
578 
579 /* fts3_expr.c */
580 int sqlite3Fts3ExprParse(sqlite3_tokenizer *, int,
581   char **, int, int, int, const char *, int, Fts3Expr **, char **
582 );
583 void sqlite3Fts3ExprFree(Fts3Expr *);
584 #ifdef SQLITE_TEST
585 int sqlite3Fts3ExprInitTestInterface(sqlite3 *db);
586 int sqlite3Fts3InitTerm(sqlite3 *db);
587 #endif
588 
589 int sqlite3Fts3OpenTokenizer(sqlite3_tokenizer *, int, const char *, int,
590   sqlite3_tokenizer_cursor **
591 );
592 
593 /* fts3_aux.c */
594 int sqlite3Fts3InitAux(sqlite3 *db);
595 
596 void sqlite3Fts3EvalPhraseCleanup(Fts3Phrase *);
597 
598 int sqlite3Fts3MsrIncrStart(
599     Fts3Table*, Fts3MultiSegReader*, int, const char*, int);
600 int sqlite3Fts3MsrIncrNext(
601     Fts3Table *, Fts3MultiSegReader *, sqlite3_int64 *, char **, int *);
602 int sqlite3Fts3EvalPhrasePoslist(Fts3Cursor *, Fts3Expr *, int iCol, char **);
603 int sqlite3Fts3MsrOvfl(Fts3Cursor *, Fts3MultiSegReader *, int *);
604 int sqlite3Fts3MsrIncrRestart(Fts3MultiSegReader *pCsr);
605 
606 /* fts3_tokenize_vtab.c */
607 int sqlite3Fts3InitTok(sqlite3*, Fts3Hash *);
608 
609 /* fts3_unicode2.c (functions generated by parsing unicode text files) */
610 #ifndef SQLITE_DISABLE_FTS3_UNICODE
611 int sqlite3FtsUnicodeFold(int, int);
612 int sqlite3FtsUnicodeIsalnum(int);
613 int sqlite3FtsUnicodeIsdiacritic(int);
614 #endif
615 
616 #endif /* !SQLITE_CORE || SQLITE_ENABLE_FTS3 */
617 #endif /* _FTSINT_H */
618