Finish refactoring of DomCodeToUsLayoutKeyboardCode().
[chromium-blink-merge.git] / third_party / sqlite / sqlite-src-3080704 / ext / fts3 / fts3_aux.c
blobc68b1a9d9be93f40b6ff81a0dddc0bfe7e0d4cfe
1 /*
2 ** 2011 Jan 27
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.
11 ******************************************************************************
14 #include "fts3Int.h"
15 #if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
17 #include <string.h>
18 #include <assert.h>
20 typedef struct Fts3auxTable Fts3auxTable;
21 typedef struct Fts3auxCursor Fts3auxCursor;
23 struct Fts3auxTable {
24 sqlite3_vtab base; /* Base class used by SQLite core */
25 Fts3Table *pFts3Tab;
28 struct Fts3auxCursor {
29 sqlite3_vtab_cursor base; /* Base class used by SQLite core */
30 Fts3MultiSegReader csr; /* Must be right after "base" */
31 Fts3SegFilter filter;
32 char *zStop;
33 int nStop; /* Byte-length of string zStop */
34 int iLangid; /* Language id to query */
35 int isEof; /* True if cursor is at EOF */
36 sqlite3_int64 iRowid; /* Current rowid */
38 int iCol; /* Current value of 'col' column */
39 int nStat; /* Size of aStat[] array */
40 struct Fts3auxColstats {
41 sqlite3_int64 nDoc; /* 'documents' values for current csr row */
42 sqlite3_int64 nOcc; /* 'occurrences' values for current csr row */
43 } *aStat;
47 ** Schema of the terms table.
49 #define FTS3_AUX_SCHEMA \
50 "CREATE TABLE x(term, col, documents, occurrences, languageid HIDDEN)"
53 ** This function does all the work for both the xConnect and xCreate methods.
54 ** These tables have no persistent representation of their own, so xConnect
55 ** and xCreate are identical operations.
57 static int fts3auxConnectMethod(
58 sqlite3 *db, /* Database connection */
59 void *pUnused, /* Unused */
60 int argc, /* Number of elements in argv array */
61 const char * const *argv, /* xCreate/xConnect argument array */
62 sqlite3_vtab **ppVtab, /* OUT: New sqlite3_vtab object */
63 char **pzErr /* OUT: sqlite3_malloc'd error message */
65 char const *zDb; /* Name of database (e.g. "main") */
66 char const *zFts3; /* Name of fts3 table */
67 int nDb; /* Result of strlen(zDb) */
68 int nFts3; /* Result of strlen(zFts3) */
69 int nByte; /* Bytes of space to allocate here */
70 int rc; /* value returned by declare_vtab() */
71 Fts3auxTable *p; /* Virtual table object to return */
73 UNUSED_PARAMETER(pUnused);
75 /* The user should invoke this in one of two forms:
77 ** CREATE VIRTUAL TABLE xxx USING fts4aux(fts4-table);
78 ** CREATE VIRTUAL TABLE xxx USING fts4aux(fts4-table-db, fts4-table);
80 if( argc!=4 && argc!=5 ) goto bad_args;
82 zDb = argv[1];
83 nDb = (int)strlen(zDb);
84 if( argc==5 ){
85 if( nDb==4 && 0==sqlite3_strnicmp("temp", zDb, 4) ){
86 zDb = argv[3];
87 nDb = (int)strlen(zDb);
88 zFts3 = argv[4];
89 }else{
90 goto bad_args;
92 }else{
93 zFts3 = argv[3];
95 nFts3 = (int)strlen(zFts3);
97 rc = sqlite3_declare_vtab(db, FTS3_AUX_SCHEMA);
98 if( rc!=SQLITE_OK ) return rc;
100 nByte = sizeof(Fts3auxTable) + sizeof(Fts3Table) + nDb + nFts3 + 2;
101 p = (Fts3auxTable *)sqlite3_malloc(nByte);
102 if( !p ) return SQLITE_NOMEM;
103 memset(p, 0, nByte);
105 p->pFts3Tab = (Fts3Table *)&p[1];
106 p->pFts3Tab->zDb = (char *)&p->pFts3Tab[1];
107 p->pFts3Tab->zName = &p->pFts3Tab->zDb[nDb+1];
108 p->pFts3Tab->db = db;
109 p->pFts3Tab->nIndex = 1;
111 memcpy((char *)p->pFts3Tab->zDb, zDb, nDb);
112 memcpy((char *)p->pFts3Tab->zName, zFts3, nFts3);
113 sqlite3Fts3Dequote((char *)p->pFts3Tab->zName);
115 *ppVtab = (sqlite3_vtab *)p;
116 return SQLITE_OK;
118 bad_args:
119 *pzErr = sqlite3_mprintf("invalid arguments to fts4aux constructor");
120 return SQLITE_ERROR;
124 ** This function does the work for both the xDisconnect and xDestroy methods.
125 ** These tables have no persistent representation of their own, so xDisconnect
126 ** and xDestroy are identical operations.
128 static int fts3auxDisconnectMethod(sqlite3_vtab *pVtab){
129 Fts3auxTable *p = (Fts3auxTable *)pVtab;
130 Fts3Table *pFts3 = p->pFts3Tab;
131 int i;
133 /* Free any prepared statements held */
134 for(i=0; i<SizeofArray(pFts3->aStmt); i++){
135 sqlite3_finalize(pFts3->aStmt[i]);
137 sqlite3_free(pFts3->zSegmentsTbl);
138 sqlite3_free(p);
139 return SQLITE_OK;
142 #define FTS4AUX_EQ_CONSTRAINT 1
143 #define FTS4AUX_GE_CONSTRAINT 2
144 #define FTS4AUX_LE_CONSTRAINT 4
147 ** xBestIndex - Analyze a WHERE and ORDER BY clause.
149 static int fts3auxBestIndexMethod(
150 sqlite3_vtab *pVTab,
151 sqlite3_index_info *pInfo
153 int i;
154 int iEq = -1;
155 int iGe = -1;
156 int iLe = -1;
157 int iLangid = -1;
158 int iNext = 1; /* Next free argvIndex value */
160 UNUSED_PARAMETER(pVTab);
162 /* This vtab delivers always results in "ORDER BY term ASC" order. */
163 if( pInfo->nOrderBy==1
164 && pInfo->aOrderBy[0].iColumn==0
165 && pInfo->aOrderBy[0].desc==0
167 pInfo->orderByConsumed = 1;
170 /* Search for equality and range constraints on the "term" column.
171 ** And equality constraints on the hidden "languageid" column. */
172 for(i=0; i<pInfo->nConstraint; i++){
173 if( pInfo->aConstraint[i].usable ){
174 int op = pInfo->aConstraint[i].op;
175 int iCol = pInfo->aConstraint[i].iColumn;
177 if( iCol==0 ){
178 if( op==SQLITE_INDEX_CONSTRAINT_EQ ) iEq = i;
179 if( op==SQLITE_INDEX_CONSTRAINT_LT ) iLe = i;
180 if( op==SQLITE_INDEX_CONSTRAINT_LE ) iLe = i;
181 if( op==SQLITE_INDEX_CONSTRAINT_GT ) iGe = i;
182 if( op==SQLITE_INDEX_CONSTRAINT_GE ) iGe = i;
184 if( iCol==4 ){
185 if( op==SQLITE_INDEX_CONSTRAINT_EQ ) iLangid = i;
190 if( iEq>=0 ){
191 pInfo->idxNum = FTS4AUX_EQ_CONSTRAINT;
192 pInfo->aConstraintUsage[iEq].argvIndex = iNext++;
193 pInfo->estimatedCost = 5;
194 }else{
195 pInfo->idxNum = 0;
196 pInfo->estimatedCost = 20000;
197 if( iGe>=0 ){
198 pInfo->idxNum += FTS4AUX_GE_CONSTRAINT;
199 pInfo->aConstraintUsage[iGe].argvIndex = iNext++;
200 pInfo->estimatedCost /= 2;
202 if( iLe>=0 ){
203 pInfo->idxNum += FTS4AUX_LE_CONSTRAINT;
204 pInfo->aConstraintUsage[iLe].argvIndex = iNext++;
205 pInfo->estimatedCost /= 2;
208 if( iLangid>=0 ){
209 pInfo->aConstraintUsage[iLangid].argvIndex = iNext++;
210 pInfo->estimatedCost--;
213 return SQLITE_OK;
217 ** xOpen - Open a cursor.
219 static int fts3auxOpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
220 Fts3auxCursor *pCsr; /* Pointer to cursor object to return */
222 UNUSED_PARAMETER(pVTab);
224 pCsr = (Fts3auxCursor *)sqlite3_malloc(sizeof(Fts3auxCursor));
225 if( !pCsr ) return SQLITE_NOMEM;
226 memset(pCsr, 0, sizeof(Fts3auxCursor));
228 *ppCsr = (sqlite3_vtab_cursor *)pCsr;
229 return SQLITE_OK;
233 ** xClose - Close a cursor.
235 static int fts3auxCloseMethod(sqlite3_vtab_cursor *pCursor){
236 Fts3Table *pFts3 = ((Fts3auxTable *)pCursor->pVtab)->pFts3Tab;
237 Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
239 sqlite3Fts3SegmentsClose(pFts3);
240 sqlite3Fts3SegReaderFinish(&pCsr->csr);
241 sqlite3_free((void *)pCsr->filter.zTerm);
242 sqlite3_free(pCsr->zStop);
243 sqlite3_free(pCsr->aStat);
244 sqlite3_free(pCsr);
245 return SQLITE_OK;
248 static int fts3auxGrowStatArray(Fts3auxCursor *pCsr, int nSize){
249 if( nSize>pCsr->nStat ){
250 struct Fts3auxColstats *aNew;
251 aNew = (struct Fts3auxColstats *)sqlite3_realloc(pCsr->aStat,
252 sizeof(struct Fts3auxColstats) * nSize
254 if( aNew==0 ) return SQLITE_NOMEM;
255 memset(&aNew[pCsr->nStat], 0,
256 sizeof(struct Fts3auxColstats) * (nSize - pCsr->nStat)
258 pCsr->aStat = aNew;
259 pCsr->nStat = nSize;
261 return SQLITE_OK;
265 ** xNext - Advance the cursor to the next row, if any.
267 static int fts3auxNextMethod(sqlite3_vtab_cursor *pCursor){
268 Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
269 Fts3Table *pFts3 = ((Fts3auxTable *)pCursor->pVtab)->pFts3Tab;
270 int rc;
272 /* Increment our pretend rowid value. */
273 pCsr->iRowid++;
275 for(pCsr->iCol++; pCsr->iCol<pCsr->nStat; pCsr->iCol++){
276 if( pCsr->aStat[pCsr->iCol].nDoc>0 ) return SQLITE_OK;
279 rc = sqlite3Fts3SegReaderStep(pFts3, &pCsr->csr);
280 if( rc==SQLITE_ROW ){
281 int i = 0;
282 int nDoclist = pCsr->csr.nDoclist;
283 char *aDoclist = pCsr->csr.aDoclist;
284 int iCol;
286 int eState = 0;
288 if( pCsr->zStop ){
289 int n = (pCsr->nStop<pCsr->csr.nTerm) ? pCsr->nStop : pCsr->csr.nTerm;
290 int mc = memcmp(pCsr->zStop, pCsr->csr.zTerm, n);
291 if( mc<0 || (mc==0 && pCsr->csr.nTerm>pCsr->nStop) ){
292 pCsr->isEof = 1;
293 return SQLITE_OK;
297 if( fts3auxGrowStatArray(pCsr, 2) ) return SQLITE_NOMEM;
298 memset(pCsr->aStat, 0, sizeof(struct Fts3auxColstats) * pCsr->nStat);
299 iCol = 0;
301 while( i<nDoclist ){
302 sqlite3_int64 v = 0;
304 i += sqlite3Fts3GetVarint(&aDoclist[i], &v);
305 switch( eState ){
306 /* State 0. In this state the integer just read was a docid. */
307 case 0:
308 pCsr->aStat[0].nDoc++;
309 eState = 1;
310 iCol = 0;
311 break;
313 /* State 1. In this state we are expecting either a 1, indicating
314 ** that the following integer will be a column number, or the
315 ** start of a position list for column 0.
317 ** The only difference between state 1 and state 2 is that if the
318 ** integer encountered in state 1 is not 0 or 1, then we need to
319 ** increment the column 0 "nDoc" count for this term.
321 case 1:
322 assert( iCol==0 );
323 if( v>1 ){
324 pCsr->aStat[1].nDoc++;
326 eState = 2;
327 /* fall through */
329 case 2:
330 if( v==0 ){ /* 0x00. Next integer will be a docid. */
331 eState = 0;
332 }else if( v==1 ){ /* 0x01. Next integer will be a column number. */
333 eState = 3;
334 }else{ /* 2 or greater. A position. */
335 pCsr->aStat[iCol+1].nOcc++;
336 pCsr->aStat[0].nOcc++;
338 break;
340 /* State 3. The integer just read is a column number. */
341 default: assert( eState==3 );
342 iCol = (int)v;
343 if( fts3auxGrowStatArray(pCsr, iCol+2) ) return SQLITE_NOMEM;
344 pCsr->aStat[iCol+1].nDoc++;
345 eState = 2;
346 break;
350 pCsr->iCol = 0;
351 rc = SQLITE_OK;
352 }else{
353 pCsr->isEof = 1;
355 return rc;
359 ** xFilter - Initialize a cursor to point at the start of its data.
361 static int fts3auxFilterMethod(
362 sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
363 int idxNum, /* Strategy index */
364 const char *idxStr, /* Unused */
365 int nVal, /* Number of elements in apVal */
366 sqlite3_value **apVal /* Arguments for the indexing scheme */
368 Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
369 Fts3Table *pFts3 = ((Fts3auxTable *)pCursor->pVtab)->pFts3Tab;
370 int rc;
371 int isScan = 0;
372 int iLangVal = 0; /* Language id to query */
374 int iEq = -1; /* Index of term=? value in apVal */
375 int iGe = -1; /* Index of term>=? value in apVal */
376 int iLe = -1; /* Index of term<=? value in apVal */
377 int iLangid = -1; /* Index of languageid=? value in apVal */
378 int iNext = 0;
380 UNUSED_PARAMETER(nVal);
381 UNUSED_PARAMETER(idxStr);
383 assert( idxStr==0 );
384 assert( idxNum==FTS4AUX_EQ_CONSTRAINT || idxNum==0
385 || idxNum==FTS4AUX_LE_CONSTRAINT || idxNum==FTS4AUX_GE_CONSTRAINT
386 || idxNum==(FTS4AUX_LE_CONSTRAINT|FTS4AUX_GE_CONSTRAINT)
389 if( idxNum==FTS4AUX_EQ_CONSTRAINT ){
390 iEq = iNext++;
391 }else{
392 isScan = 1;
393 if( idxNum & FTS4AUX_GE_CONSTRAINT ){
394 iGe = iNext++;
396 if( idxNum & FTS4AUX_LE_CONSTRAINT ){
397 iLe = iNext++;
400 if( iNext<nVal ){
401 iLangid = iNext++;
404 /* In case this cursor is being reused, close and zero it. */
405 testcase(pCsr->filter.zTerm);
406 sqlite3Fts3SegReaderFinish(&pCsr->csr);
407 sqlite3_free((void *)pCsr->filter.zTerm);
408 sqlite3_free(pCsr->aStat);
409 memset(&pCsr->csr, 0, ((u8*)&pCsr[1]) - (u8*)&pCsr->csr);
411 pCsr->filter.flags = FTS3_SEGMENT_REQUIRE_POS|FTS3_SEGMENT_IGNORE_EMPTY;
412 if( isScan ) pCsr->filter.flags |= FTS3_SEGMENT_SCAN;
414 if( iEq>=0 || iGe>=0 ){
415 const unsigned char *zStr = sqlite3_value_text(apVal[0]);
416 assert( (iEq==0 && iGe==-1) || (iEq==-1 && iGe==0) );
417 if( zStr ){
418 pCsr->filter.zTerm = sqlite3_mprintf("%s", zStr);
419 pCsr->filter.nTerm = sqlite3_value_bytes(apVal[0]);
420 if( pCsr->filter.zTerm==0 ) return SQLITE_NOMEM;
424 if( iLe>=0 ){
425 pCsr->zStop = sqlite3_mprintf("%s", sqlite3_value_text(apVal[iLe]));
426 pCsr->nStop = sqlite3_value_bytes(apVal[iLe]);
427 if( pCsr->zStop==0 ) return SQLITE_NOMEM;
430 if( iLangid>=0 ){
431 iLangVal = sqlite3_value_int(apVal[iLangid]);
433 /* If the user specified a negative value for the languageid, use zero
434 ** instead. This works, as the "languageid=?" constraint will also
435 ** be tested by the VDBE layer. The test will always be false (since
436 ** this module will not return a row with a negative languageid), and
437 ** so the overall query will return zero rows. */
438 if( iLangVal<0 ) iLangVal = 0;
440 pCsr->iLangid = iLangVal;
442 rc = sqlite3Fts3SegReaderCursor(pFts3, iLangVal, 0, FTS3_SEGCURSOR_ALL,
443 pCsr->filter.zTerm, pCsr->filter.nTerm, 0, isScan, &pCsr->csr
445 if( rc==SQLITE_OK ){
446 rc = sqlite3Fts3SegReaderStart(pFts3, &pCsr->csr, &pCsr->filter);
449 if( rc==SQLITE_OK ) rc = fts3auxNextMethod(pCursor);
450 return rc;
454 ** xEof - Return true if the cursor is at EOF, or false otherwise.
456 static int fts3auxEofMethod(sqlite3_vtab_cursor *pCursor){
457 Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
458 return pCsr->isEof;
462 ** xColumn - Return a column value.
464 static int fts3auxColumnMethod(
465 sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
466 sqlite3_context *pCtx, /* Context for sqlite3_result_xxx() calls */
467 int iCol /* Index of column to read value from */
469 Fts3auxCursor *p = (Fts3auxCursor *)pCursor;
471 assert( p->isEof==0 );
472 switch( iCol ){
473 case 0: /* term */
474 sqlite3_result_text(pCtx, p->csr.zTerm, p->csr.nTerm, SQLITE_TRANSIENT);
475 break;
477 case 1: /* col */
478 if( p->iCol ){
479 sqlite3_result_int(pCtx, p->iCol-1);
480 }else{
481 sqlite3_result_text(pCtx, "*", -1, SQLITE_STATIC);
483 break;
485 case 2: /* documents */
486 sqlite3_result_int64(pCtx, p->aStat[p->iCol].nDoc);
487 break;
489 case 3: /* occurrences */
490 sqlite3_result_int64(pCtx, p->aStat[p->iCol].nOcc);
491 break;
493 default: /* languageid */
494 assert( iCol==4 );
495 sqlite3_result_int(pCtx, p->iLangid);
496 break;
499 return SQLITE_OK;
503 ** xRowid - Return the current rowid for the cursor.
505 static int fts3auxRowidMethod(
506 sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
507 sqlite_int64 *pRowid /* OUT: Rowid value */
509 Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
510 *pRowid = pCsr->iRowid;
511 return SQLITE_OK;
515 ** Register the fts3aux module with database connection db. Return SQLITE_OK
516 ** if successful or an error code if sqlite3_create_module() fails.
518 int sqlite3Fts3InitAux(sqlite3 *db){
519 static const sqlite3_module fts3aux_module = {
520 0, /* iVersion */
521 fts3auxConnectMethod, /* xCreate */
522 fts3auxConnectMethod, /* xConnect */
523 fts3auxBestIndexMethod, /* xBestIndex */
524 fts3auxDisconnectMethod, /* xDisconnect */
525 fts3auxDisconnectMethod, /* xDestroy */
526 fts3auxOpenMethod, /* xOpen */
527 fts3auxCloseMethod, /* xClose */
528 fts3auxFilterMethod, /* xFilter */
529 fts3auxNextMethod, /* xNext */
530 fts3auxEofMethod, /* xEof */
531 fts3auxColumnMethod, /* xColumn */
532 fts3auxRowidMethod, /* xRowid */
533 0, /* xUpdate */
534 0, /* xBegin */
535 0, /* xSync */
536 0, /* xCommit */
537 0, /* xRollback */
538 0, /* xFindFunction */
539 0, /* xRename */
540 0, /* xSavepoint */
541 0, /* xRelease */
542 0 /* xRollbackTo */
544 int rc; /* Return code */
546 rc = sqlite3_create_module(db, "fts4aux", &fts3aux_module, 0);
547 return rc;
550 #endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */