1 | /*------------------------------------------------------------------------- |
2 | * |
3 | * dict_thesaurus.c |
4 | * Thesaurus dictionary: phrase to phrase substitution |
5 | * |
6 | * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group |
7 | * |
8 | * |
9 | * IDENTIFICATION |
10 | * src/backend/tsearch/dict_thesaurus.c |
11 | * |
12 | *------------------------------------------------------------------------- |
13 | */ |
14 | #include "postgres.h" |
15 | |
16 | #include "catalog/namespace.h" |
17 | #include "commands/defrem.h" |
18 | #include "tsearch/ts_cache.h" |
19 | #include "tsearch/ts_locale.h" |
20 | #include "tsearch/ts_utils.h" |
21 | #include "utils/builtins.h" |
22 | #include "utils/regproc.h" |
23 | |
24 | |
25 | /* |
26 | * Temporary we use TSLexeme.flags for inner use... |
27 | */ |
28 | #define DT_USEASIS 0x1000 |
29 | |
30 | typedef struct LexemeInfo |
31 | { |
32 | uint32 idsubst; /* entry's number in DictThesaurus->subst */ |
33 | uint16 posinsubst; /* pos info in entry */ |
34 | uint16 tnvariant; /* total num lexemes in one variant */ |
35 | struct LexemeInfo *nextentry; |
36 | struct LexemeInfo *nextvariant; |
37 | } LexemeInfo; |
38 | |
39 | typedef struct |
40 | { |
41 | char *lexeme; |
42 | LexemeInfo *entries; |
43 | } TheLexeme; |
44 | |
45 | typedef struct |
46 | { |
47 | uint16 lastlexeme; /* number lexemes to substitute */ |
48 | uint16 reslen; |
49 | TSLexeme *res; /* prepared substituted result */ |
50 | } TheSubstitute; |
51 | |
52 | typedef struct |
53 | { |
54 | /* subdictionary to normalize lexemes */ |
55 | Oid subdictOid; |
56 | TSDictionaryCacheEntry *subdict; |
57 | |
58 | /* Array to search lexeme by exact match */ |
59 | TheLexeme *wrds; |
60 | int nwrds; /* current number of words */ |
61 | int ntwrds; /* allocated array length */ |
62 | |
63 | /* |
64 | * Storage of substituted result, n-th element is for n-th expression |
65 | */ |
66 | TheSubstitute *subst; |
67 | int nsubst; |
68 | } DictThesaurus; |
69 | |
70 | |
71 | static void |
72 | newLexeme(DictThesaurus *d, char *b, char *e, uint32 idsubst, uint16 posinsubst) |
73 | { |
74 | TheLexeme *ptr; |
75 | |
76 | if (d->nwrds >= d->ntwrds) |
77 | { |
78 | if (d->ntwrds == 0) |
79 | { |
80 | d->ntwrds = 16; |
81 | d->wrds = (TheLexeme *) palloc(sizeof(TheLexeme) * d->ntwrds); |
82 | } |
83 | else |
84 | { |
85 | d->ntwrds *= 2; |
86 | d->wrds = (TheLexeme *) repalloc(d->wrds, sizeof(TheLexeme) * d->ntwrds); |
87 | } |
88 | } |
89 | |
90 | ptr = d->wrds + d->nwrds; |
91 | d->nwrds++; |
92 | |
93 | ptr->lexeme = palloc(e - b + 1); |
94 | |
95 | memcpy(ptr->lexeme, b, e - b); |
96 | ptr->lexeme[e - b] = '\0'; |
97 | |
98 | ptr->entries = (LexemeInfo *) palloc(sizeof(LexemeInfo)); |
99 | |
100 | ptr->entries->nextentry = NULL; |
101 | ptr->entries->idsubst = idsubst; |
102 | ptr->entries->posinsubst = posinsubst; |
103 | } |
104 | |
105 | static void |
106 | addWrd(DictThesaurus *d, char *b, char *e, uint32 idsubst, uint16 nwrd, uint16 posinsubst, bool useasis) |
107 | { |
108 | static int nres = 0; |
109 | static int ntres = 0; |
110 | TheSubstitute *ptr; |
111 | |
112 | if (nwrd == 0) |
113 | { |
114 | nres = ntres = 0; |
115 | |
116 | if (idsubst >= d->nsubst) |
117 | { |
118 | if (d->nsubst == 0) |
119 | { |
120 | d->nsubst = 16; |
121 | d->subst = (TheSubstitute *) palloc(sizeof(TheSubstitute) * d->nsubst); |
122 | } |
123 | else |
124 | { |
125 | d->nsubst *= 2; |
126 | d->subst = (TheSubstitute *) repalloc(d->subst, sizeof(TheSubstitute) * d->nsubst); |
127 | } |
128 | } |
129 | } |
130 | |
131 | ptr = d->subst + idsubst; |
132 | |
133 | ptr->lastlexeme = posinsubst - 1; |
134 | |
135 | if (nres + 1 >= ntres) |
136 | { |
137 | if (ntres == 0) |
138 | { |
139 | ntres = 2; |
140 | ptr->res = (TSLexeme *) palloc(sizeof(TSLexeme) * ntres); |
141 | } |
142 | else |
143 | { |
144 | ntres *= 2; |
145 | ptr->res = (TSLexeme *) repalloc(ptr->res, sizeof(TSLexeme) * ntres); |
146 | } |
147 | } |
148 | |
149 | ptr->res[nres].lexeme = palloc(e - b + 1); |
150 | memcpy(ptr->res[nres].lexeme, b, e - b); |
151 | ptr->res[nres].lexeme[e - b] = '\0'; |
152 | |
153 | ptr->res[nres].nvariant = nwrd; |
154 | if (useasis) |
155 | ptr->res[nres].flags = DT_USEASIS; |
156 | else |
157 | ptr->res[nres].flags = 0; |
158 | |
159 | ptr->res[++nres].lexeme = NULL; |
160 | } |
161 | |
162 | #define TR_WAITLEX 1 |
163 | #define TR_INLEX 2 |
164 | #define TR_WAITSUBS 3 |
165 | #define TR_INSUBS 4 |
166 | |
167 | static void |
168 | thesaurusRead(const char *filename, DictThesaurus *d) |
169 | { |
170 | tsearch_readline_state trst; |
171 | uint32 idsubst = 0; |
172 | bool useasis = false; |
173 | char *line; |
174 | |
175 | filename = get_tsearch_config_filename(filename, "ths" ); |
176 | if (!tsearch_readline_begin(&trst, filename)) |
177 | ereport(ERROR, |
178 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
179 | errmsg("could not open thesaurus file \"%s\": %m" , |
180 | filename))); |
181 | |
182 | while ((line = tsearch_readline(&trst)) != NULL) |
183 | { |
184 | char *ptr; |
185 | int state = TR_WAITLEX; |
186 | char *beginwrd = NULL; |
187 | uint32 posinsubst = 0; |
188 | uint32 nwrd = 0; |
189 | |
190 | ptr = line; |
191 | |
192 | /* is it a comment? */ |
193 | while (*ptr && t_isspace(ptr)) |
194 | ptr += pg_mblen(ptr); |
195 | |
196 | if (t_iseq(ptr, '#') || *ptr == '\0' || |
197 | t_iseq(ptr, '\n') || t_iseq(ptr, '\r')) |
198 | { |
199 | pfree(line); |
200 | continue; |
201 | } |
202 | |
203 | while (*ptr) |
204 | { |
205 | if (state == TR_WAITLEX) |
206 | { |
207 | if (t_iseq(ptr, ':')) |
208 | { |
209 | if (posinsubst == 0) |
210 | ereport(ERROR, |
211 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
212 | errmsg("unexpected delimiter" ))); |
213 | state = TR_WAITSUBS; |
214 | } |
215 | else if (!t_isspace(ptr)) |
216 | { |
217 | beginwrd = ptr; |
218 | state = TR_INLEX; |
219 | } |
220 | } |
221 | else if (state == TR_INLEX) |
222 | { |
223 | if (t_iseq(ptr, ':')) |
224 | { |
225 | newLexeme(d, beginwrd, ptr, idsubst, posinsubst++); |
226 | state = TR_WAITSUBS; |
227 | } |
228 | else if (t_isspace(ptr)) |
229 | { |
230 | newLexeme(d, beginwrd, ptr, idsubst, posinsubst++); |
231 | state = TR_WAITLEX; |
232 | } |
233 | } |
234 | else if (state == TR_WAITSUBS) |
235 | { |
236 | if (t_iseq(ptr, '*')) |
237 | { |
238 | useasis = true; |
239 | state = TR_INSUBS; |
240 | beginwrd = ptr + pg_mblen(ptr); |
241 | } |
242 | else if (t_iseq(ptr, '\\')) |
243 | { |
244 | useasis = false; |
245 | state = TR_INSUBS; |
246 | beginwrd = ptr + pg_mblen(ptr); |
247 | } |
248 | else if (!t_isspace(ptr)) |
249 | { |
250 | useasis = false; |
251 | beginwrd = ptr; |
252 | state = TR_INSUBS; |
253 | } |
254 | } |
255 | else if (state == TR_INSUBS) |
256 | { |
257 | if (t_isspace(ptr)) |
258 | { |
259 | if (ptr == beginwrd) |
260 | ereport(ERROR, |
261 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
262 | errmsg("unexpected end of line or lexeme" ))); |
263 | addWrd(d, beginwrd, ptr, idsubst, nwrd++, posinsubst, useasis); |
264 | state = TR_WAITSUBS; |
265 | } |
266 | } |
267 | else |
268 | elog(ERROR, "unrecognized thesaurus state: %d" , state); |
269 | |
270 | ptr += pg_mblen(ptr); |
271 | } |
272 | |
273 | if (state == TR_INSUBS) |
274 | { |
275 | if (ptr == beginwrd) |
276 | ereport(ERROR, |
277 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
278 | errmsg("unexpected end of line or lexeme" ))); |
279 | addWrd(d, beginwrd, ptr, idsubst, nwrd++, posinsubst, useasis); |
280 | } |
281 | |
282 | idsubst++; |
283 | |
284 | if (!(nwrd && posinsubst)) |
285 | ereport(ERROR, |
286 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
287 | errmsg("unexpected end of line" ))); |
288 | |
289 | /* |
290 | * Note: currently, tsearch_readline can't return lines exceeding 4KB, |
291 | * so overflow of the word counts is impossible. But that may not |
292 | * always be true, so let's check. |
293 | */ |
294 | if (nwrd != (uint16) nwrd || posinsubst != (uint16) posinsubst) |
295 | ereport(ERROR, |
296 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
297 | errmsg("too many lexemes in thesaurus entry" ))); |
298 | |
299 | pfree(line); |
300 | } |
301 | |
302 | d->nsubst = idsubst; |
303 | |
304 | tsearch_readline_end(&trst); |
305 | } |
306 | |
307 | static TheLexeme * |
308 | addCompiledLexeme(TheLexeme *newwrds, int *nnw, int *tnm, TSLexeme *lexeme, LexemeInfo *src, uint16 tnvariant) |
309 | { |
310 | if (*nnw >= *tnm) |
311 | { |
312 | *tnm *= 2; |
313 | newwrds = (TheLexeme *) repalloc(newwrds, sizeof(TheLexeme) * *tnm); |
314 | } |
315 | |
316 | newwrds[*nnw].entries = (LexemeInfo *) palloc(sizeof(LexemeInfo)); |
317 | |
318 | if (lexeme && lexeme->lexeme) |
319 | { |
320 | newwrds[*nnw].lexeme = pstrdup(lexeme->lexeme); |
321 | newwrds[*nnw].entries->tnvariant = tnvariant; |
322 | } |
323 | else |
324 | { |
325 | newwrds[*nnw].lexeme = NULL; |
326 | newwrds[*nnw].entries->tnvariant = 1; |
327 | } |
328 | |
329 | newwrds[*nnw].entries->idsubst = src->idsubst; |
330 | newwrds[*nnw].entries->posinsubst = src->posinsubst; |
331 | |
332 | newwrds[*nnw].entries->nextentry = NULL; |
333 | |
334 | (*nnw)++; |
335 | return newwrds; |
336 | } |
337 | |
338 | static int |
339 | cmpLexemeInfo(LexemeInfo *a, LexemeInfo *b) |
340 | { |
341 | if (a == NULL || b == NULL) |
342 | return 0; |
343 | |
344 | if (a->idsubst == b->idsubst) |
345 | { |
346 | if (a->posinsubst == b->posinsubst) |
347 | { |
348 | if (a->tnvariant == b->tnvariant) |
349 | return 0; |
350 | |
351 | return (a->tnvariant > b->tnvariant) ? 1 : -1; |
352 | } |
353 | |
354 | return (a->posinsubst > b->posinsubst) ? 1 : -1; |
355 | } |
356 | |
357 | return (a->idsubst > b->idsubst) ? 1 : -1; |
358 | } |
359 | |
360 | static int |
361 | cmpLexeme(const TheLexeme *a, const TheLexeme *b) |
362 | { |
363 | if (a->lexeme == NULL) |
364 | { |
365 | if (b->lexeme == NULL) |
366 | return 0; |
367 | else |
368 | return 1; |
369 | } |
370 | else if (b->lexeme == NULL) |
371 | return -1; |
372 | |
373 | return strcmp(a->lexeme, b->lexeme); |
374 | } |
375 | |
376 | static int |
377 | cmpLexemeQ(const void *a, const void *b) |
378 | { |
379 | return cmpLexeme((const TheLexeme *) a, (const TheLexeme *) b); |
380 | } |
381 | |
382 | static int |
383 | cmpTheLexeme(const void *a, const void *b) |
384 | { |
385 | const TheLexeme *la = (const TheLexeme *) a; |
386 | const TheLexeme *lb = (const TheLexeme *) b; |
387 | int res; |
388 | |
389 | if ((res = cmpLexeme(la, lb)) != 0) |
390 | return res; |
391 | |
392 | return -cmpLexemeInfo(la->entries, lb->entries); |
393 | } |
394 | |
395 | static void |
396 | compileTheLexeme(DictThesaurus *d) |
397 | { |
398 | int i, |
399 | nnw = 0, |
400 | tnm = 16; |
401 | TheLexeme *newwrds = (TheLexeme *) palloc(sizeof(TheLexeme) * tnm), |
402 | *ptrwrds; |
403 | |
404 | for (i = 0; i < d->nwrds; i++) |
405 | { |
406 | TSLexeme *ptr; |
407 | |
408 | if (strcmp(d->wrds[i].lexeme, "?" ) == 0) /* Is stop word marker? */ |
409 | newwrds = addCompiledLexeme(newwrds, &nnw, &tnm, NULL, d->wrds[i].entries, 0); |
410 | else |
411 | { |
412 | ptr = (TSLexeme *) DatumGetPointer(FunctionCall4(&(d->subdict->lexize), |
413 | PointerGetDatum(d->subdict->dictData), |
414 | PointerGetDatum(d->wrds[i].lexeme), |
415 | Int32GetDatum(strlen(d->wrds[i].lexeme)), |
416 | PointerGetDatum(NULL))); |
417 | |
418 | if (!ptr) |
419 | ereport(ERROR, |
420 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
421 | errmsg("thesaurus sample word \"%s\" isn't recognized by subdictionary (rule %d)" , |
422 | d->wrds[i].lexeme, |
423 | d->wrds[i].entries->idsubst + 1))); |
424 | else if (!(ptr->lexeme)) |
425 | ereport(ERROR, |
426 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
427 | errmsg("thesaurus sample word \"%s\" is a stop word (rule %d)" , |
428 | d->wrds[i].lexeme, |
429 | d->wrds[i].entries->idsubst + 1), |
430 | errhint("Use \"?\" to represent a stop word within a sample phrase." ))); |
431 | else |
432 | { |
433 | while (ptr->lexeme) |
434 | { |
435 | TSLexeme *remptr = ptr + 1; |
436 | int tnvar = 1; |
437 | int curvar = ptr->nvariant; |
438 | |
439 | /* compute n words in one variant */ |
440 | while (remptr->lexeme) |
441 | { |
442 | if (remptr->nvariant != (remptr - 1)->nvariant) |
443 | break; |
444 | tnvar++; |
445 | remptr++; |
446 | } |
447 | |
448 | remptr = ptr; |
449 | while (remptr->lexeme && remptr->nvariant == curvar) |
450 | { |
451 | newwrds = addCompiledLexeme(newwrds, &nnw, &tnm, remptr, d->wrds[i].entries, tnvar); |
452 | remptr++; |
453 | } |
454 | |
455 | ptr = remptr; |
456 | } |
457 | } |
458 | } |
459 | |
460 | pfree(d->wrds[i].lexeme); |
461 | pfree(d->wrds[i].entries); |
462 | } |
463 | |
464 | if (d->wrds) |
465 | pfree(d->wrds); |
466 | d->wrds = newwrds; |
467 | d->nwrds = nnw; |
468 | d->ntwrds = tnm; |
469 | |
470 | if (d->nwrds > 1) |
471 | { |
472 | qsort(d->wrds, d->nwrds, sizeof(TheLexeme), cmpTheLexeme); |
473 | |
474 | /* uniq */ |
475 | newwrds = d->wrds; |
476 | ptrwrds = d->wrds + 1; |
477 | while (ptrwrds - d->wrds < d->nwrds) |
478 | { |
479 | if (cmpLexeme(ptrwrds, newwrds) == 0) |
480 | { |
481 | if (cmpLexemeInfo(ptrwrds->entries, newwrds->entries)) |
482 | { |
483 | ptrwrds->entries->nextentry = newwrds->entries; |
484 | newwrds->entries = ptrwrds->entries; |
485 | } |
486 | else |
487 | pfree(ptrwrds->entries); |
488 | |
489 | if (ptrwrds->lexeme) |
490 | pfree(ptrwrds->lexeme); |
491 | } |
492 | else |
493 | { |
494 | newwrds++; |
495 | *newwrds = *ptrwrds; |
496 | } |
497 | |
498 | ptrwrds++; |
499 | } |
500 | |
501 | d->nwrds = newwrds - d->wrds + 1; |
502 | d->wrds = (TheLexeme *) repalloc(d->wrds, sizeof(TheLexeme) * d->nwrds); |
503 | } |
504 | } |
505 | |
506 | static void |
507 | compileTheSubstitute(DictThesaurus *d) |
508 | { |
509 | int i; |
510 | |
511 | for (i = 0; i < d->nsubst; i++) |
512 | { |
513 | TSLexeme *rem = d->subst[i].res, |
514 | *outptr, |
515 | *inptr; |
516 | int n = 2; |
517 | |
518 | outptr = d->subst[i].res = (TSLexeme *) palloc(sizeof(TSLexeme) * n); |
519 | outptr->lexeme = NULL; |
520 | inptr = rem; |
521 | |
522 | while (inptr && inptr->lexeme) |
523 | { |
524 | TSLexeme *lexized, |
525 | tmplex[2]; |
526 | |
527 | if (inptr->flags & DT_USEASIS) |
528 | { /* do not lexize */ |
529 | tmplex[0] = *inptr; |
530 | tmplex[0].flags = 0; |
531 | tmplex[1].lexeme = NULL; |
532 | lexized = tmplex; |
533 | } |
534 | else |
535 | { |
536 | lexized = (TSLexeme *) DatumGetPointer( |
537 | FunctionCall4( |
538 | &(d->subdict->lexize), |
539 | PointerGetDatum(d->subdict->dictData), |
540 | PointerGetDatum(inptr->lexeme), |
541 | Int32GetDatum(strlen(inptr->lexeme)), |
542 | PointerGetDatum(NULL) |
543 | ) |
544 | ); |
545 | } |
546 | |
547 | if (lexized && lexized->lexeme) |
548 | { |
549 | int toset = (lexized->lexeme && outptr != d->subst[i].res) ? (outptr - d->subst[i].res) : -1; |
550 | |
551 | while (lexized->lexeme) |
552 | { |
553 | if (outptr - d->subst[i].res + 1 >= n) |
554 | { |
555 | int diff = outptr - d->subst[i].res; |
556 | |
557 | n *= 2; |
558 | d->subst[i].res = (TSLexeme *) repalloc(d->subst[i].res, sizeof(TSLexeme) * n); |
559 | outptr = d->subst[i].res + diff; |
560 | } |
561 | |
562 | *outptr = *lexized; |
563 | outptr->lexeme = pstrdup(lexized->lexeme); |
564 | |
565 | outptr++; |
566 | lexized++; |
567 | } |
568 | |
569 | if (toset > 0) |
570 | d->subst[i].res[toset].flags |= TSL_ADDPOS; |
571 | } |
572 | else if (lexized) |
573 | { |
574 | ereport(ERROR, |
575 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
576 | errmsg("thesaurus substitute word \"%s\" is a stop word (rule %d)" , |
577 | inptr->lexeme, i + 1))); |
578 | } |
579 | else |
580 | { |
581 | ereport(ERROR, |
582 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
583 | errmsg("thesaurus substitute word \"%s\" isn't recognized by subdictionary (rule %d)" , |
584 | inptr->lexeme, i + 1))); |
585 | } |
586 | |
587 | if (inptr->lexeme) |
588 | pfree(inptr->lexeme); |
589 | inptr++; |
590 | } |
591 | |
592 | if (outptr == d->subst[i].res) |
593 | ereport(ERROR, |
594 | (errcode(ERRCODE_CONFIG_FILE_ERROR), |
595 | errmsg("thesaurus substitute phrase is empty (rule %d)" , |
596 | i + 1))); |
597 | |
598 | d->subst[i].reslen = outptr - d->subst[i].res; |
599 | |
600 | pfree(rem); |
601 | } |
602 | } |
603 | |
604 | Datum |
605 | thesaurus_init(PG_FUNCTION_ARGS) |
606 | { |
607 | List *dictoptions = (List *) PG_GETARG_POINTER(0); |
608 | DictThesaurus *d; |
609 | char *subdictname = NULL; |
610 | bool fileloaded = false; |
611 | ListCell *l; |
612 | |
613 | d = (DictThesaurus *) palloc0(sizeof(DictThesaurus)); |
614 | |
615 | foreach(l, dictoptions) |
616 | { |
617 | DefElem *defel = (DefElem *) lfirst(l); |
618 | |
619 | if (strcmp(defel->defname, "dictfile" ) == 0) |
620 | { |
621 | if (fileloaded) |
622 | ereport(ERROR, |
623 | (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
624 | errmsg("multiple DictFile parameters" ))); |
625 | thesaurusRead(defGetString(defel), d); |
626 | fileloaded = true; |
627 | } |
628 | else if (strcmp(defel->defname, "dictionary" ) == 0) |
629 | { |
630 | if (subdictname) |
631 | ereport(ERROR, |
632 | (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
633 | errmsg("multiple Dictionary parameters" ))); |
634 | subdictname = pstrdup(defGetString(defel)); |
635 | } |
636 | else |
637 | { |
638 | ereport(ERROR, |
639 | (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
640 | errmsg("unrecognized Thesaurus parameter: \"%s\"" , |
641 | defel->defname))); |
642 | } |
643 | } |
644 | |
645 | if (!fileloaded) |
646 | ereport(ERROR, |
647 | (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
648 | errmsg("missing DictFile parameter" ))); |
649 | if (!subdictname) |
650 | ereport(ERROR, |
651 | (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
652 | errmsg("missing Dictionary parameter" ))); |
653 | |
654 | d->subdictOid = get_ts_dict_oid(stringToQualifiedNameList(subdictname), false); |
655 | d->subdict = lookup_ts_dictionary_cache(d->subdictOid); |
656 | |
657 | compileTheLexeme(d); |
658 | compileTheSubstitute(d); |
659 | |
660 | PG_RETURN_POINTER(d); |
661 | } |
662 | |
663 | static LexemeInfo * |
664 | findTheLexeme(DictThesaurus *d, char *lexeme) |
665 | { |
666 | TheLexeme key, |
667 | *res; |
668 | |
669 | if (d->nwrds == 0) |
670 | return NULL; |
671 | |
672 | key.lexeme = lexeme; |
673 | key.entries = NULL; |
674 | |
675 | res = bsearch(&key, d->wrds, d->nwrds, sizeof(TheLexeme), cmpLexemeQ); |
676 | |
677 | if (res == NULL) |
678 | return NULL; |
679 | return res->entries; |
680 | } |
681 | |
682 | static bool |
683 | matchIdSubst(LexemeInfo *stored, uint32 idsubst) |
684 | { |
685 | bool res = true; |
686 | |
687 | if (stored) |
688 | { |
689 | res = false; |
690 | |
691 | for (; stored; stored = stored->nextvariant) |
692 | if (stored->idsubst == idsubst) |
693 | { |
694 | res = true; |
695 | break; |
696 | } |
697 | } |
698 | |
699 | return res; |
700 | } |
701 | |
702 | static LexemeInfo * |
703 | findVariant(LexemeInfo *in, LexemeInfo *stored, uint16 curpos, LexemeInfo **newin, int newn) |
704 | { |
705 | for (;;) |
706 | { |
707 | int i; |
708 | LexemeInfo *ptr = newin[0]; |
709 | |
710 | for (i = 0; i < newn; i++) |
711 | { |
712 | while (newin[i] && newin[i]->idsubst < ptr->idsubst) |
713 | newin[i] = newin[i]->nextentry; |
714 | |
715 | if (newin[i] == NULL) |
716 | return in; |
717 | |
718 | if (newin[i]->idsubst > ptr->idsubst) |
719 | { |
720 | ptr = newin[i]; |
721 | i = -1; |
722 | continue; |
723 | } |
724 | |
725 | while (newin[i]->idsubst == ptr->idsubst) |
726 | { |
727 | if (newin[i]->posinsubst == curpos && newin[i]->tnvariant == newn) |
728 | { |
729 | ptr = newin[i]; |
730 | break; |
731 | } |
732 | |
733 | newin[i] = newin[i]->nextentry; |
734 | if (newin[i] == NULL) |
735 | return in; |
736 | } |
737 | |
738 | if (newin[i]->idsubst != ptr->idsubst) |
739 | { |
740 | ptr = newin[i]; |
741 | i = -1; |
742 | continue; |
743 | } |
744 | } |
745 | |
746 | if (i == newn && matchIdSubst(stored, ptr->idsubst) && (in == NULL || !matchIdSubst(in, ptr->idsubst))) |
747 | { /* found */ |
748 | |
749 | ptr->nextvariant = in; |
750 | in = ptr; |
751 | } |
752 | |
753 | /* step forward */ |
754 | for (i = 0; i < newn; i++) |
755 | newin[i] = newin[i]->nextentry; |
756 | } |
757 | } |
758 | |
759 | static TSLexeme * |
760 | copyTSLexeme(TheSubstitute *ts) |
761 | { |
762 | TSLexeme *res; |
763 | uint16 i; |
764 | |
765 | res = (TSLexeme *) palloc(sizeof(TSLexeme) * (ts->reslen + 1)); |
766 | for (i = 0; i < ts->reslen; i++) |
767 | { |
768 | res[i] = ts->res[i]; |
769 | res[i].lexeme = pstrdup(ts->res[i].lexeme); |
770 | } |
771 | |
772 | res[ts->reslen].lexeme = NULL; |
773 | |
774 | return res; |
775 | } |
776 | |
777 | static TSLexeme * |
778 | checkMatch(DictThesaurus *d, LexemeInfo *info, uint16 curpos, bool *moreres) |
779 | { |
780 | *moreres = false; |
781 | while (info) |
782 | { |
783 | Assert(info->idsubst < d->nsubst); |
784 | if (info->nextvariant) |
785 | *moreres = true; |
786 | if (d->subst[info->idsubst].lastlexeme == curpos) |
787 | return copyTSLexeme(d->subst + info->idsubst); |
788 | info = info->nextvariant; |
789 | } |
790 | |
791 | return NULL; |
792 | } |
793 | |
794 | Datum |
795 | thesaurus_lexize(PG_FUNCTION_ARGS) |
796 | { |
797 | DictThesaurus *d = (DictThesaurus *) PG_GETARG_POINTER(0); |
798 | DictSubState *dstate = (DictSubState *) PG_GETARG_POINTER(3); |
799 | TSLexeme *res = NULL; |
800 | LexemeInfo *stored, |
801 | *info = NULL; |
802 | uint16 curpos = 0; |
803 | bool moreres = false; |
804 | |
805 | if (PG_NARGS() != 4 || dstate == NULL) |
806 | elog(ERROR, "forbidden call of thesaurus or nested call" ); |
807 | |
808 | if (dstate->isend) |
809 | PG_RETURN_POINTER(NULL); |
810 | stored = (LexemeInfo *) dstate->private_state; |
811 | |
812 | if (stored) |
813 | curpos = stored->posinsubst + 1; |
814 | |
815 | if (!d->subdict->isvalid) |
816 | d->subdict = lookup_ts_dictionary_cache(d->subdictOid); |
817 | |
818 | res = (TSLexeme *) DatumGetPointer(FunctionCall4(&(d->subdict->lexize), |
819 | PointerGetDatum(d->subdict->dictData), |
820 | PG_GETARG_DATUM(1), |
821 | PG_GETARG_DATUM(2), |
822 | PointerGetDatum(NULL))); |
823 | |
824 | if (res && res->lexeme) |
825 | { |
826 | TSLexeme *ptr = res, |
827 | *basevar; |
828 | |
829 | while (ptr->lexeme) |
830 | { |
831 | uint16 nv = ptr->nvariant; |
832 | uint16 i, |
833 | nlex = 0; |
834 | LexemeInfo **infos; |
835 | |
836 | basevar = ptr; |
837 | while (ptr->lexeme && nv == ptr->nvariant) |
838 | { |
839 | nlex++; |
840 | ptr++; |
841 | } |
842 | |
843 | infos = (LexemeInfo **) palloc(sizeof(LexemeInfo *) * nlex); |
844 | for (i = 0; i < nlex; i++) |
845 | if ((infos[i] = findTheLexeme(d, basevar[i].lexeme)) == NULL) |
846 | break; |
847 | |
848 | if (i < nlex) |
849 | { |
850 | /* no chance to find */ |
851 | pfree(infos); |
852 | continue; |
853 | } |
854 | |
855 | info = findVariant(info, stored, curpos, infos, nlex); |
856 | } |
857 | } |
858 | else if (res) |
859 | { /* stop-word */ |
860 | LexemeInfo *infos = findTheLexeme(d, NULL); |
861 | |
862 | info = findVariant(NULL, stored, curpos, &infos, 1); |
863 | } |
864 | else |
865 | { |
866 | info = NULL; /* word isn't recognized */ |
867 | } |
868 | |
869 | dstate->private_state = (void *) info; |
870 | |
871 | if (!info) |
872 | { |
873 | dstate->getnext = false; |
874 | PG_RETURN_POINTER(NULL); |
875 | } |
876 | |
877 | if ((res = checkMatch(d, info, curpos, &moreres)) != NULL) |
878 | { |
879 | dstate->getnext = moreres; |
880 | PG_RETURN_POINTER(res); |
881 | } |
882 | |
883 | dstate->getnext = true; |
884 | |
885 | PG_RETURN_POINTER(NULL); |
886 | } |
887 | |