1 | /*------------------------------------------------------------------------- |
2 | * |
3 | * tsquery.c |
4 | * I/O functions for tsquery |
5 | * |
6 | * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group |
7 | * |
8 | * |
9 | * IDENTIFICATION |
10 | * src/backend/utils/adt/tsquery.c |
11 | * |
12 | *------------------------------------------------------------------------- |
13 | */ |
14 | |
15 | #include "postgres.h" |
16 | |
17 | #include "libpq/pqformat.h" |
18 | #include "miscadmin.h" |
19 | #include "tsearch/ts_type.h" |
20 | #include "tsearch/ts_locale.h" |
21 | #include "tsearch/ts_utils.h" |
22 | #include "utils/builtins.h" |
23 | #include "utils/memutils.h" |
24 | #include "utils/pg_crc.h" |
25 | |
26 | /* FTS operator priorities, see ts_type.h */ |
27 | const int tsearch_op_priority[OP_COUNT] = |
28 | { |
29 | 4, /* OP_NOT */ |
30 | 2, /* OP_AND */ |
31 | 1, /* OP_OR */ |
32 | 3 /* OP_PHRASE */ |
33 | }; |
34 | |
35 | /* |
36 | * parser's states |
37 | */ |
38 | typedef enum |
39 | { |
40 | WAITOPERAND = 1, |
41 | WAITOPERATOR = 2, |
42 | WAITFIRSTOPERAND = 3 |
43 | } ts_parserstate; |
44 | |
45 | /* |
46 | * token types for parsing |
47 | */ |
48 | typedef enum |
49 | { |
50 | PT_END = 0, |
51 | PT_ERR = 1, |
52 | PT_VAL = 2, |
53 | PT_OPR = 3, |
54 | PT_OPEN = 4, |
55 | PT_CLOSE = 5 |
56 | } ts_tokentype; |
57 | |
58 | /* |
59 | * get token from query string |
60 | * |
61 | * *operator is filled in with OP_* when return values is PT_OPR, |
62 | * but *weight could contain a distance value in case of phrase operator. |
63 | * *strval, *lenval and *weight are filled in when return value is PT_VAL |
64 | * |
65 | */ |
66 | typedef ts_tokentype (*ts_tokenizer) (TSQueryParserState state, int8 *operator, |
67 | int *lenval, char **strval, |
68 | int16 *weight, bool *prefix); |
69 | |
70 | struct TSQueryParserStateData |
71 | { |
72 | /* Tokenizer used for parsing tsquery */ |
73 | ts_tokenizer gettoken; |
74 | |
75 | /* State of tokenizer function */ |
76 | char *buffer; /* entire string we are scanning */ |
77 | char *buf; /* current scan point */ |
78 | int count; /* nesting count, incremented by (, |
79 | * decremented by ) */ |
80 | bool in_quotes; /* phrase in quotes "" */ |
81 | ts_parserstate state; |
82 | |
83 | /* polish (prefix) notation in list, filled in by push* functions */ |
84 | List *polstr; |
85 | |
86 | /* |
87 | * Strings from operands are collected in op. curop is a pointer to the |
88 | * end of used space of op. |
89 | */ |
90 | char *op; |
91 | char *curop; |
92 | int lenop; /* allocated size of op */ |
93 | int sumlen; /* used size of op */ |
94 | |
95 | /* state for value's parser */ |
96 | TSVectorParseState valstate; |
97 | }; |
98 | |
99 | /* |
100 | * subroutine to parse the modifiers (weight and prefix flag currently) |
101 | * part, like ':AB*' of a query. |
102 | */ |
103 | static char * |
104 | get_modifiers(char *buf, int16 *weight, bool *prefix) |
105 | { |
106 | *weight = 0; |
107 | *prefix = false; |
108 | |
109 | if (!t_iseq(buf, ':')) |
110 | return buf; |
111 | |
112 | buf++; |
113 | while (*buf && pg_mblen(buf) == 1) |
114 | { |
115 | switch (*buf) |
116 | { |
117 | case 'a': |
118 | case 'A': |
119 | *weight |= 1 << 3; |
120 | break; |
121 | case 'b': |
122 | case 'B': |
123 | *weight |= 1 << 2; |
124 | break; |
125 | case 'c': |
126 | case 'C': |
127 | *weight |= 1 << 1; |
128 | break; |
129 | case 'd': |
130 | case 'D': |
131 | *weight |= 1; |
132 | break; |
133 | case '*': |
134 | *prefix = true; |
135 | break; |
136 | default: |
137 | return buf; |
138 | } |
139 | buf++; |
140 | } |
141 | |
142 | return buf; |
143 | } |
144 | |
145 | /* |
146 | * Parse phrase operator. The operator |
147 | * may take the following forms: |
148 | * |
149 | * a <N> b (distance is exactly N lexemes) |
150 | * a <-> b (default distance = 1) |
151 | * |
152 | * The buffer should begin with '<' char |
153 | */ |
154 | static bool |
155 | parse_phrase_operator(TSQueryParserState pstate, int16 *distance) |
156 | { |
157 | enum |
158 | { |
159 | PHRASE_OPEN = 0, |
160 | PHRASE_DIST, |
161 | PHRASE_CLOSE, |
162 | PHRASE_FINISH |
163 | } state = PHRASE_OPEN; |
164 | char *ptr = pstate->buf; |
165 | char *endptr; |
166 | long l = 1; /* default distance */ |
167 | |
168 | while (*ptr) |
169 | { |
170 | switch (state) |
171 | { |
172 | case PHRASE_OPEN: |
173 | if (t_iseq(ptr, '<')) |
174 | { |
175 | state = PHRASE_DIST; |
176 | ptr++; |
177 | } |
178 | else |
179 | return false; |
180 | break; |
181 | |
182 | case PHRASE_DIST: |
183 | if (t_iseq(ptr, '-')) |
184 | { |
185 | state = PHRASE_CLOSE; |
186 | ptr++; |
187 | continue; |
188 | } |
189 | |
190 | if (!t_isdigit(ptr)) |
191 | return false; |
192 | |
193 | errno = 0; |
194 | l = strtol(ptr, &endptr, 10); |
195 | if (ptr == endptr) |
196 | return false; |
197 | else if (errno == ERANGE || l < 0 || l > MAXENTRYPOS) |
198 | ereport(ERROR, |
199 | (errcode(ERRCODE_INVALID_PARAMETER_VALUE), |
200 | errmsg("distance in phrase operator should not be greater than %d" , |
201 | MAXENTRYPOS))); |
202 | else |
203 | { |
204 | state = PHRASE_CLOSE; |
205 | ptr = endptr; |
206 | } |
207 | break; |
208 | |
209 | case PHRASE_CLOSE: |
210 | if (t_iseq(ptr, '>')) |
211 | { |
212 | state = PHRASE_FINISH; |
213 | ptr++; |
214 | } |
215 | else |
216 | return false; |
217 | break; |
218 | |
219 | case PHRASE_FINISH: |
220 | *distance = (int16) l; |
221 | pstate->buf = ptr; |
222 | return true; |
223 | } |
224 | } |
225 | |
226 | return false; |
227 | } |
228 | |
229 | /* |
230 | * Parse OR operator used in websearch_to_tsquery(), returns true if we |
231 | * believe that "OR" literal could be an operator OR |
232 | */ |
233 | static bool |
234 | parse_or_operator(TSQueryParserState pstate) |
235 | { |
236 | char *ptr = pstate->buf; |
237 | |
238 | if (pstate->in_quotes) |
239 | return false; |
240 | |
241 | /* it should begin with "OR" literal */ |
242 | if (pg_strncasecmp(ptr, "or" , 2) != 0) |
243 | return false; |
244 | |
245 | ptr += 2; |
246 | |
247 | /* |
248 | * it shouldn't be a part of any word but somewhere later it should be |
249 | * some operand |
250 | */ |
251 | if (*ptr == '\0') /* no operand */ |
252 | return false; |
253 | |
254 | /* it shouldn't be a part of any word */ |
255 | if (t_iseq(ptr, '-') || t_iseq(ptr, '_') || t_isalpha(ptr) || t_isdigit(ptr)) |
256 | return false; |
257 | |
258 | for (;;) |
259 | { |
260 | ptr += pg_mblen(ptr); |
261 | |
262 | if (*ptr == '\0') /* got end of string without operand */ |
263 | return false; |
264 | |
265 | /* |
266 | * Suppose, we found an operand, but could be a not correct operand. |
267 | * So we still treat OR literal as operation with possibly incorrect |
268 | * operand and will not search it as lexeme |
269 | */ |
270 | if (!t_isspace(ptr)) |
271 | break; |
272 | } |
273 | |
274 | pstate->buf += 2; |
275 | return true; |
276 | } |
277 | |
278 | static ts_tokentype |
279 | gettoken_query_standard(TSQueryParserState state, int8 *operator, |
280 | int *lenval, char **strval, |
281 | int16 *weight, bool *prefix) |
282 | { |
283 | *weight = 0; |
284 | *prefix = false; |
285 | |
286 | while (true) |
287 | { |
288 | switch (state->state) |
289 | { |
290 | case WAITFIRSTOPERAND: |
291 | case WAITOPERAND: |
292 | if (t_iseq(state->buf, '!')) |
293 | { |
294 | state->buf++; |
295 | state->state = WAITOPERAND; |
296 | *operator = OP_NOT; |
297 | return PT_OPR; |
298 | } |
299 | else if (t_iseq(state->buf, '(')) |
300 | { |
301 | state->buf++; |
302 | state->state = WAITOPERAND; |
303 | state->count++; |
304 | return PT_OPEN; |
305 | } |
306 | else if (t_iseq(state->buf, ':')) |
307 | { |
308 | ereport(ERROR, |
309 | (errcode(ERRCODE_SYNTAX_ERROR), |
310 | errmsg("syntax error in tsquery: \"%s\"" , |
311 | state->buffer))); |
312 | } |
313 | else if (!t_isspace(state->buf)) |
314 | { |
315 | /* |
316 | * We rely on the tsvector parser to parse the value for |
317 | * us |
318 | */ |
319 | reset_tsvector_parser(state->valstate, state->buf); |
320 | if (gettoken_tsvector(state->valstate, strval, lenval, |
321 | NULL, NULL, &state->buf)) |
322 | { |
323 | state->buf = get_modifiers(state->buf, weight, prefix); |
324 | state->state = WAITOPERATOR; |
325 | return PT_VAL; |
326 | } |
327 | else if (state->state == WAITFIRSTOPERAND) |
328 | { |
329 | return PT_END; |
330 | } |
331 | else |
332 | ereport(ERROR, |
333 | (errcode(ERRCODE_SYNTAX_ERROR), |
334 | errmsg("no operand in tsquery: \"%s\"" , |
335 | state->buffer))); |
336 | } |
337 | break; |
338 | |
339 | case WAITOPERATOR: |
340 | if (t_iseq(state->buf, '&')) |
341 | { |
342 | state->buf++; |
343 | state->state = WAITOPERAND; |
344 | *operator = OP_AND; |
345 | return PT_OPR; |
346 | } |
347 | else if (t_iseq(state->buf, '|')) |
348 | { |
349 | state->buf++; |
350 | state->state = WAITOPERAND; |
351 | *operator = OP_OR; |
352 | return PT_OPR; |
353 | } |
354 | else if (parse_phrase_operator(state, weight)) |
355 | { |
356 | /* weight var is used as storage for distance */ |
357 | state->state = WAITOPERAND; |
358 | *operator = OP_PHRASE; |
359 | return PT_OPR; |
360 | } |
361 | else if (t_iseq(state->buf, ')')) |
362 | { |
363 | state->buf++; |
364 | state->count--; |
365 | return (state->count < 0) ? PT_ERR : PT_CLOSE; |
366 | } |
367 | else if (*state->buf == '\0') |
368 | { |
369 | return (state->count) ? PT_ERR : PT_END; |
370 | } |
371 | else if (!t_isspace(state->buf)) |
372 | { |
373 | return PT_ERR; |
374 | } |
375 | break; |
376 | } |
377 | |
378 | state->buf += pg_mblen(state->buf); |
379 | } |
380 | } |
381 | |
382 | static ts_tokentype |
383 | gettoken_query_websearch(TSQueryParserState state, int8 *operator, |
384 | int *lenval, char **strval, |
385 | int16 *weight, bool *prefix) |
386 | { |
387 | *weight = 0; |
388 | *prefix = false; |
389 | |
390 | while (true) |
391 | { |
392 | switch (state->state) |
393 | { |
394 | case WAITFIRSTOPERAND: |
395 | case WAITOPERAND: |
396 | if (t_iseq(state->buf, '-')) |
397 | { |
398 | state->buf++; |
399 | state->state = WAITOPERAND; |
400 | |
401 | if (state->in_quotes) |
402 | continue; |
403 | |
404 | *operator = OP_NOT; |
405 | return PT_OPR; |
406 | } |
407 | else if (t_iseq(state->buf, '"')) |
408 | { |
409 | state->buf++; |
410 | |
411 | if (!state->in_quotes) |
412 | { |
413 | state->state = WAITOPERAND; |
414 | |
415 | if (strchr(state->buf, '"')) |
416 | { |
417 | /* quoted text should be ordered <-> */ |
418 | state->in_quotes = true; |
419 | return PT_OPEN; |
420 | } |
421 | |
422 | /* web search tolerates missing quotes */ |
423 | continue; |
424 | } |
425 | else |
426 | { |
427 | /* we have to provide an operand */ |
428 | state->in_quotes = false; |
429 | state->state = WAITOPERATOR; |
430 | pushStop(state); |
431 | return PT_CLOSE; |
432 | } |
433 | } |
434 | else if (ISOPERATOR(state->buf)) |
435 | { |
436 | /* or else gettoken_tsvector() will raise an error */ |
437 | state->buf++; |
438 | state->state = WAITOPERAND; |
439 | continue; |
440 | } |
441 | else if (!t_isspace(state->buf)) |
442 | { |
443 | /* |
444 | * We rely on the tsvector parser to parse the value for |
445 | * us |
446 | */ |
447 | reset_tsvector_parser(state->valstate, state->buf); |
448 | if (gettoken_tsvector(state->valstate, strval, lenval, |
449 | NULL, NULL, &state->buf)) |
450 | { |
451 | state->state = WAITOPERATOR; |
452 | return PT_VAL; |
453 | } |
454 | else if (state->state == WAITFIRSTOPERAND) |
455 | { |
456 | return PT_END; |
457 | } |
458 | else |
459 | { |
460 | /* finally, we have to provide an operand */ |
461 | pushStop(state); |
462 | return PT_END; |
463 | } |
464 | } |
465 | break; |
466 | |
467 | case WAITOPERATOR: |
468 | if (t_iseq(state->buf, '"')) |
469 | { |
470 | if (!state->in_quotes) |
471 | { |
472 | /* |
473 | * put implicit AND after an operand and handle this |
474 | * quote in WAITOPERAND |
475 | */ |
476 | state->state = WAITOPERAND; |
477 | *operator = OP_AND; |
478 | return PT_OPR; |
479 | } |
480 | else |
481 | { |
482 | state->buf++; |
483 | |
484 | /* just close quotes */ |
485 | state->in_quotes = false; |
486 | return PT_CLOSE; |
487 | } |
488 | } |
489 | else if (parse_or_operator(state)) |
490 | { |
491 | state->state = WAITOPERAND; |
492 | *operator = OP_OR; |
493 | return PT_OPR; |
494 | } |
495 | else if (*state->buf == '\0') |
496 | { |
497 | return PT_END; |
498 | } |
499 | else if (!t_isspace(state->buf)) |
500 | { |
501 | if (state->in_quotes) |
502 | { |
503 | /* put implicit <-> after an operand */ |
504 | *operator = OP_PHRASE; |
505 | *weight = 1; |
506 | } |
507 | else |
508 | { |
509 | /* put implicit AND after an operand */ |
510 | *operator = OP_AND; |
511 | } |
512 | |
513 | state->state = WAITOPERAND; |
514 | return PT_OPR; |
515 | } |
516 | break; |
517 | } |
518 | |
519 | state->buf += pg_mblen(state->buf); |
520 | } |
521 | } |
522 | |
523 | static ts_tokentype |
524 | gettoken_query_plain(TSQueryParserState state, int8 *operator, |
525 | int *lenval, char **strval, |
526 | int16 *weight, bool *prefix) |
527 | { |
528 | *weight = 0; |
529 | *prefix = false; |
530 | |
531 | if (*state->buf == '\0') |
532 | return PT_END; |
533 | |
534 | *strval = state->buf; |
535 | *lenval = strlen(state->buf); |
536 | state->buf += *lenval; |
537 | state->count++; |
538 | return PT_VAL; |
539 | } |
540 | |
541 | /* |
542 | * Push an operator to state->polstr |
543 | */ |
544 | void |
545 | pushOperator(TSQueryParserState state, int8 oper, int16 distance) |
546 | { |
547 | QueryOperator *tmp; |
548 | |
549 | Assert(oper == OP_NOT || oper == OP_AND || oper == OP_OR || oper == OP_PHRASE); |
550 | |
551 | tmp = (QueryOperator *) palloc0(sizeof(QueryOperator)); |
552 | tmp->type = QI_OPR; |
553 | tmp->oper = oper; |
554 | tmp->distance = (oper == OP_PHRASE) ? distance : 0; |
555 | /* left is filled in later with findoprnd */ |
556 | |
557 | state->polstr = lcons(tmp, state->polstr); |
558 | } |
559 | |
560 | static void |
561 | pushValue_internal(TSQueryParserState state, pg_crc32 valcrc, int distance, int lenval, int weight, bool prefix) |
562 | { |
563 | QueryOperand *tmp; |
564 | |
565 | if (distance >= MAXSTRPOS) |
566 | ereport(ERROR, |
567 | (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), |
568 | errmsg("value is too big in tsquery: \"%s\"" , |
569 | state->buffer))); |
570 | if (lenval >= MAXSTRLEN) |
571 | ereport(ERROR, |
572 | (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), |
573 | errmsg("operand is too long in tsquery: \"%s\"" , |
574 | state->buffer))); |
575 | |
576 | tmp = (QueryOperand *) palloc0(sizeof(QueryOperand)); |
577 | tmp->type = QI_VAL; |
578 | tmp->weight = weight; |
579 | tmp->prefix = prefix; |
580 | tmp->valcrc = (int32) valcrc; |
581 | tmp->length = lenval; |
582 | tmp->distance = distance; |
583 | |
584 | state->polstr = lcons(tmp, state->polstr); |
585 | } |
586 | |
587 | /* |
588 | * Push an operand to state->polstr. |
589 | * |
590 | * strval must point to a string equal to state->curop. lenval is the length |
591 | * of the string. |
592 | */ |
593 | void |
594 | pushValue(TSQueryParserState state, char *strval, int lenval, int16 weight, bool prefix) |
595 | { |
596 | pg_crc32 valcrc; |
597 | |
598 | if (lenval >= MAXSTRLEN) |
599 | ereport(ERROR, |
600 | (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), |
601 | errmsg("word is too long in tsquery: \"%s\"" , |
602 | state->buffer))); |
603 | |
604 | INIT_LEGACY_CRC32(valcrc); |
605 | COMP_LEGACY_CRC32(valcrc, strval, lenval); |
606 | FIN_LEGACY_CRC32(valcrc); |
607 | pushValue_internal(state, valcrc, state->curop - state->op, lenval, weight, prefix); |
608 | |
609 | /* append the value string to state.op, enlarging buffer if needed first */ |
610 | while (state->curop - state->op + lenval + 1 >= state->lenop) |
611 | { |
612 | int used = state->curop - state->op; |
613 | |
614 | state->lenop *= 2; |
615 | state->op = (char *) repalloc((void *) state->op, state->lenop); |
616 | state->curop = state->op + used; |
617 | } |
618 | memcpy((void *) state->curop, (void *) strval, lenval); |
619 | state->curop += lenval; |
620 | *(state->curop) = '\0'; |
621 | state->curop++; |
622 | state->sumlen += lenval + 1 /* \0 */ ; |
623 | } |
624 | |
625 | |
626 | /* |
627 | * Push a stopword placeholder to state->polstr |
628 | */ |
629 | void |
630 | pushStop(TSQueryParserState state) |
631 | { |
632 | QueryOperand *tmp; |
633 | |
634 | tmp = (QueryOperand *) palloc0(sizeof(QueryOperand)); |
635 | tmp->type = QI_VALSTOP; |
636 | |
637 | state->polstr = lcons(tmp, state->polstr); |
638 | } |
639 | |
640 | |
641 | #define STACKDEPTH 32 |
642 | |
643 | typedef struct OperatorElement |
644 | { |
645 | int8 op; |
646 | int16 distance; |
647 | } OperatorElement; |
648 | |
649 | static void |
650 | pushOpStack(OperatorElement *stack, int *lenstack, int8 op, int16 distance) |
651 | { |
652 | if (*lenstack == STACKDEPTH) /* internal error */ |
653 | elog(ERROR, "tsquery stack too small" ); |
654 | |
655 | stack[*lenstack].op = op; |
656 | stack[*lenstack].distance = distance; |
657 | |
658 | (*lenstack)++; |
659 | } |
660 | |
661 | static void |
662 | cleanOpStack(TSQueryParserState state, |
663 | OperatorElement *stack, int *lenstack, int8 op) |
664 | { |
665 | int opPriority = OP_PRIORITY(op); |
666 | |
667 | while (*lenstack) |
668 | { |
669 | /* NOT is right associative unlike to others */ |
670 | if ((op != OP_NOT && opPriority > OP_PRIORITY(stack[*lenstack - 1].op)) || |
671 | (op == OP_NOT && opPriority >= OP_PRIORITY(stack[*lenstack - 1].op))) |
672 | break; |
673 | |
674 | (*lenstack)--; |
675 | pushOperator(state, stack[*lenstack].op, |
676 | stack[*lenstack].distance); |
677 | } |
678 | } |
679 | |
680 | /* |
681 | * Make polish (prefix) notation of query. |
682 | * |
683 | * See parse_tsquery for explanation of pushval. |
684 | */ |
685 | static void |
686 | makepol(TSQueryParserState state, |
687 | PushFunction pushval, |
688 | Datum opaque) |
689 | { |
690 | int8 operator = 0; |
691 | ts_tokentype type; |
692 | int lenval = 0; |
693 | char *strval = NULL; |
694 | OperatorElement opstack[STACKDEPTH]; |
695 | int lenstack = 0; |
696 | int16 weight = 0; |
697 | bool prefix; |
698 | |
699 | /* since this function recurses, it could be driven to stack overflow */ |
700 | check_stack_depth(); |
701 | |
702 | while ((type = state->gettoken(state, &operator, |
703 | &lenval, &strval, |
704 | &weight, &prefix)) != PT_END) |
705 | { |
706 | switch (type) |
707 | { |
708 | case PT_VAL: |
709 | pushval(opaque, state, strval, lenval, weight, prefix); |
710 | break; |
711 | case PT_OPR: |
712 | cleanOpStack(state, opstack, &lenstack, operator); |
713 | pushOpStack(opstack, &lenstack, operator, weight); |
714 | break; |
715 | case PT_OPEN: |
716 | makepol(state, pushval, opaque); |
717 | break; |
718 | case PT_CLOSE: |
719 | cleanOpStack(state, opstack, &lenstack, OP_OR /* lowest */ ); |
720 | return; |
721 | case PT_ERR: |
722 | default: |
723 | ereport(ERROR, |
724 | (errcode(ERRCODE_SYNTAX_ERROR), |
725 | errmsg("syntax error in tsquery: \"%s\"" , |
726 | state->buffer))); |
727 | } |
728 | } |
729 | |
730 | cleanOpStack(state, opstack, &lenstack, OP_OR /* lowest */ ); |
731 | } |
732 | |
733 | static void |
734 | findoprnd_recurse(QueryItem *ptr, uint32 *pos, int nnodes, bool *needcleanup) |
735 | { |
736 | /* since this function recurses, it could be driven to stack overflow. */ |
737 | check_stack_depth(); |
738 | |
739 | if (*pos >= nnodes) |
740 | elog(ERROR, "malformed tsquery: operand not found" ); |
741 | |
742 | if (ptr[*pos].type == QI_VAL) |
743 | { |
744 | (*pos)++; |
745 | } |
746 | else if (ptr[*pos].type == QI_VALSTOP) |
747 | { |
748 | *needcleanup = true; /* we'll have to remove stop words */ |
749 | (*pos)++; |
750 | } |
751 | else |
752 | { |
753 | Assert(ptr[*pos].type == QI_OPR); |
754 | |
755 | if (ptr[*pos].qoperator.oper == OP_NOT) |
756 | { |
757 | ptr[*pos].qoperator.left = 1; /* fixed offset */ |
758 | (*pos)++; |
759 | |
760 | /* process the only argument */ |
761 | findoprnd_recurse(ptr, pos, nnodes, needcleanup); |
762 | } |
763 | else |
764 | { |
765 | QueryOperator *curitem = &ptr[*pos].qoperator; |
766 | int tmp = *pos; /* save current position */ |
767 | |
768 | Assert(curitem->oper == OP_AND || |
769 | curitem->oper == OP_OR || |
770 | curitem->oper == OP_PHRASE); |
771 | |
772 | (*pos)++; |
773 | |
774 | /* process RIGHT argument */ |
775 | findoprnd_recurse(ptr, pos, nnodes, needcleanup); |
776 | |
777 | curitem->left = *pos - tmp; /* set LEFT arg's offset */ |
778 | |
779 | /* process LEFT argument */ |
780 | findoprnd_recurse(ptr, pos, nnodes, needcleanup); |
781 | } |
782 | } |
783 | } |
784 | |
785 | |
786 | /* |
787 | * Fill in the left-fields previously left unfilled. |
788 | * The input QueryItems must be in polish (prefix) notation. |
789 | * Also, set *needcleanup to true if there are any QI_VALSTOP nodes. |
790 | */ |
791 | static void |
792 | findoprnd(QueryItem *ptr, int size, bool *needcleanup) |
793 | { |
794 | uint32 pos; |
795 | |
796 | *needcleanup = false; |
797 | pos = 0; |
798 | findoprnd_recurse(ptr, &pos, size, needcleanup); |
799 | |
800 | if (pos != size) |
801 | elog(ERROR, "malformed tsquery: extra nodes" ); |
802 | } |
803 | |
804 | |
805 | /* |
806 | * Each value (operand) in the query is passed to pushval. pushval can |
807 | * transform the simple value to an arbitrarily complex expression using |
808 | * pushValue and pushOperator. It must push a single value with pushValue, |
809 | * a complete expression with all operands, or a stopword placeholder |
810 | * with pushStop, otherwise the prefix notation representation will be broken, |
811 | * having an operator with no operand. |
812 | * |
813 | * opaque is passed on to pushval as is, pushval can use it to store its |
814 | * private state. |
815 | */ |
816 | TSQuery |
817 | parse_tsquery(char *buf, |
818 | PushFunction pushval, |
819 | Datum opaque, |
820 | int flags) |
821 | { |
822 | struct TSQueryParserStateData state; |
823 | int i; |
824 | TSQuery query; |
825 | int commonlen; |
826 | QueryItem *ptr; |
827 | ListCell *cell; |
828 | bool needcleanup; |
829 | int tsv_flags = P_TSV_OPR_IS_DELIM | P_TSV_IS_TSQUERY; |
830 | |
831 | /* plain should not be used with web */ |
832 | Assert((flags & (P_TSQ_PLAIN | P_TSQ_WEB)) != (P_TSQ_PLAIN | P_TSQ_WEB)); |
833 | |
834 | /* select suitable tokenizer */ |
835 | if (flags & P_TSQ_PLAIN) |
836 | state.gettoken = gettoken_query_plain; |
837 | else if (flags & P_TSQ_WEB) |
838 | { |
839 | state.gettoken = gettoken_query_websearch; |
840 | tsv_flags |= P_TSV_IS_WEB; |
841 | } |
842 | else |
843 | state.gettoken = gettoken_query_standard; |
844 | |
845 | /* init state */ |
846 | state.buffer = buf; |
847 | state.buf = buf; |
848 | state.count = 0; |
849 | state.in_quotes = false; |
850 | state.state = WAITFIRSTOPERAND; |
851 | state.polstr = NIL; |
852 | |
853 | /* init value parser's state */ |
854 | state.valstate = init_tsvector_parser(state.buffer, tsv_flags); |
855 | |
856 | /* init list of operand */ |
857 | state.sumlen = 0; |
858 | state.lenop = 64; |
859 | state.curop = state.op = (char *) palloc(state.lenop); |
860 | *(state.curop) = '\0'; |
861 | |
862 | /* parse query & make polish notation (postfix, but in reverse order) */ |
863 | makepol(&state, pushval, opaque); |
864 | |
865 | close_tsvector_parser(state.valstate); |
866 | |
867 | if (list_length(state.polstr) == 0) |
868 | { |
869 | ereport(NOTICE, |
870 | (errmsg("text-search query doesn't contain lexemes: \"%s\"" , |
871 | state.buffer))); |
872 | query = (TSQuery) palloc(HDRSIZETQ); |
873 | SET_VARSIZE(query, HDRSIZETQ); |
874 | query->size = 0; |
875 | return query; |
876 | } |
877 | |
878 | if (TSQUERY_TOO_BIG(list_length(state.polstr), state.sumlen)) |
879 | ereport(ERROR, |
880 | (errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED), |
881 | errmsg("tsquery is too large" ))); |
882 | commonlen = COMPUTESIZE(list_length(state.polstr), state.sumlen); |
883 | |
884 | /* Pack the QueryItems in the final TSQuery struct to return to caller */ |
885 | query = (TSQuery) palloc0(commonlen); |
886 | SET_VARSIZE(query, commonlen); |
887 | query->size = list_length(state.polstr); |
888 | ptr = GETQUERY(query); |
889 | |
890 | /* Copy QueryItems to TSQuery */ |
891 | i = 0; |
892 | foreach(cell, state.polstr) |
893 | { |
894 | QueryItem *item = (QueryItem *) lfirst(cell); |
895 | |
896 | switch (item->type) |
897 | { |
898 | case QI_VAL: |
899 | memcpy(&ptr[i], item, sizeof(QueryOperand)); |
900 | break; |
901 | case QI_VALSTOP: |
902 | ptr[i].type = QI_VALSTOP; |
903 | break; |
904 | case QI_OPR: |
905 | memcpy(&ptr[i], item, sizeof(QueryOperator)); |
906 | break; |
907 | default: |
908 | elog(ERROR, "unrecognized QueryItem type: %d" , item->type); |
909 | } |
910 | i++; |
911 | } |
912 | |
913 | /* Copy all the operand strings to TSQuery */ |
914 | memcpy((void *) GETOPERAND(query), (void *) state.op, state.sumlen); |
915 | pfree(state.op); |
916 | |
917 | /* |
918 | * Set left operand pointers for every operator. While we're at it, |
919 | * detect whether there are any QI_VALSTOP nodes. |
920 | */ |
921 | findoprnd(ptr, query->size, &needcleanup); |
922 | |
923 | /* |
924 | * If there are QI_VALSTOP nodes, delete them and simplify the tree. |
925 | */ |
926 | if (needcleanup) |
927 | query = cleanup_tsquery_stopwords(query); |
928 | |
929 | return query; |
930 | } |
931 | |
932 | static void |
933 | pushval_asis(Datum opaque, TSQueryParserState state, char *strval, int lenval, |
934 | int16 weight, bool prefix) |
935 | { |
936 | pushValue(state, strval, lenval, weight, prefix); |
937 | } |
938 | |
939 | /* |
940 | * in without morphology |
941 | */ |
942 | Datum |
943 | tsqueryin(PG_FUNCTION_ARGS) |
944 | { |
945 | char *in = PG_GETARG_CSTRING(0); |
946 | |
947 | PG_RETURN_TSQUERY(parse_tsquery(in, pushval_asis, PointerGetDatum(NULL), 0)); |
948 | } |
949 | |
950 | /* |
951 | * out function |
952 | */ |
953 | typedef struct |
954 | { |
955 | QueryItem *curpol; |
956 | char *buf; |
957 | char *cur; |
958 | char *op; |
959 | int buflen; |
960 | } INFIX; |
961 | |
962 | /* Makes sure inf->buf is large enough for adding 'addsize' bytes */ |
963 | #define RESIZEBUF(inf, addsize) \ |
964 | while( ( (inf)->cur - (inf)->buf ) + (addsize) + 1 >= (inf)->buflen ) \ |
965 | { \ |
966 | int len = (inf)->cur - (inf)->buf; \ |
967 | (inf)->buflen *= 2; \ |
968 | (inf)->buf = (char*) repalloc( (void*)(inf)->buf, (inf)->buflen ); \ |
969 | (inf)->cur = (inf)->buf + len; \ |
970 | } |
971 | |
972 | /* |
973 | * recursively traverse the tree and |
974 | * print it in infix (human-readable) form |
975 | */ |
976 | static void |
977 | infix(INFIX *in, int parentPriority, bool rightPhraseOp) |
978 | { |
979 | /* since this function recurses, it could be driven to stack overflow. */ |
980 | check_stack_depth(); |
981 | |
982 | if (in->curpol->type == QI_VAL) |
983 | { |
984 | QueryOperand *curpol = &in->curpol->qoperand; |
985 | char *op = in->op + curpol->distance; |
986 | int clen; |
987 | |
988 | RESIZEBUF(in, curpol->length * (pg_database_encoding_max_length() + 1) + 2 + 6); |
989 | *(in->cur) = '\''; |
990 | in->cur++; |
991 | while (*op) |
992 | { |
993 | if (t_iseq(op, '\'')) |
994 | { |
995 | *(in->cur) = '\''; |
996 | in->cur++; |
997 | } |
998 | else if (t_iseq(op, '\\')) |
999 | { |
1000 | *(in->cur) = '\\'; |
1001 | in->cur++; |
1002 | } |
1003 | COPYCHAR(in->cur, op); |
1004 | |
1005 | clen = pg_mblen(op); |
1006 | op += clen; |
1007 | in->cur += clen; |
1008 | } |
1009 | *(in->cur) = '\''; |
1010 | in->cur++; |
1011 | if (curpol->weight || curpol->prefix) |
1012 | { |
1013 | *(in->cur) = ':'; |
1014 | in->cur++; |
1015 | if (curpol->prefix) |
1016 | { |
1017 | *(in->cur) = '*'; |
1018 | in->cur++; |
1019 | } |
1020 | if (curpol->weight & (1 << 3)) |
1021 | { |
1022 | *(in->cur) = 'A'; |
1023 | in->cur++; |
1024 | } |
1025 | if (curpol->weight & (1 << 2)) |
1026 | { |
1027 | *(in->cur) = 'B'; |
1028 | in->cur++; |
1029 | } |
1030 | if (curpol->weight & (1 << 1)) |
1031 | { |
1032 | *(in->cur) = 'C'; |
1033 | in->cur++; |
1034 | } |
1035 | if (curpol->weight & 1) |
1036 | { |
1037 | *(in->cur) = 'D'; |
1038 | in->cur++; |
1039 | } |
1040 | } |
1041 | *(in->cur) = '\0'; |
1042 | in->curpol++; |
1043 | } |
1044 | else if (in->curpol->qoperator.oper == OP_NOT) |
1045 | { |
1046 | int priority = QO_PRIORITY(in->curpol); |
1047 | |
1048 | if (priority < parentPriority) |
1049 | { |
1050 | RESIZEBUF(in, 2); |
1051 | sprintf(in->cur, "( " ); |
1052 | in->cur = strchr(in->cur, '\0'); |
1053 | } |
1054 | RESIZEBUF(in, 1); |
1055 | *(in->cur) = '!'; |
1056 | in->cur++; |
1057 | *(in->cur) = '\0'; |
1058 | in->curpol++; |
1059 | |
1060 | infix(in, priority, false); |
1061 | if (priority < parentPriority) |
1062 | { |
1063 | RESIZEBUF(in, 2); |
1064 | sprintf(in->cur, " )" ); |
1065 | in->cur = strchr(in->cur, '\0'); |
1066 | } |
1067 | } |
1068 | else |
1069 | { |
1070 | int8 op = in->curpol->qoperator.oper; |
1071 | int priority = QO_PRIORITY(in->curpol); |
1072 | int16 distance = in->curpol->qoperator.distance; |
1073 | INFIX nrm; |
1074 | bool needParenthesis = false; |
1075 | |
1076 | in->curpol++; |
1077 | if (priority < parentPriority || |
1078 | /* phrase operator depends on order */ |
1079 | (op == OP_PHRASE && rightPhraseOp)) |
1080 | { |
1081 | needParenthesis = true; |
1082 | RESIZEBUF(in, 2); |
1083 | sprintf(in->cur, "( " ); |
1084 | in->cur = strchr(in->cur, '\0'); |
1085 | } |
1086 | |
1087 | nrm.curpol = in->curpol; |
1088 | nrm.op = in->op; |
1089 | nrm.buflen = 16; |
1090 | nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen); |
1091 | |
1092 | /* get right operand */ |
1093 | infix(&nrm, priority, (op == OP_PHRASE)); |
1094 | |
1095 | /* get & print left operand */ |
1096 | in->curpol = nrm.curpol; |
1097 | infix(in, priority, false); |
1098 | |
1099 | /* print operator & right operand */ |
1100 | RESIZEBUF(in, 3 + (2 + 10 /* distance */ ) + (nrm.cur - nrm.buf)); |
1101 | switch (op) |
1102 | { |
1103 | case OP_OR: |
1104 | sprintf(in->cur, " | %s" , nrm.buf); |
1105 | break; |
1106 | case OP_AND: |
1107 | sprintf(in->cur, " & %s" , nrm.buf); |
1108 | break; |
1109 | case OP_PHRASE: |
1110 | if (distance != 1) |
1111 | sprintf(in->cur, " <%d> %s" , distance, nrm.buf); |
1112 | else |
1113 | sprintf(in->cur, " <-> %s" , nrm.buf); |
1114 | break; |
1115 | default: |
1116 | /* OP_NOT is handled in above if-branch */ |
1117 | elog(ERROR, "unrecognized operator type: %d" , op); |
1118 | } |
1119 | in->cur = strchr(in->cur, '\0'); |
1120 | pfree(nrm.buf); |
1121 | |
1122 | if (needParenthesis) |
1123 | { |
1124 | RESIZEBUF(in, 2); |
1125 | sprintf(in->cur, " )" ); |
1126 | in->cur = strchr(in->cur, '\0'); |
1127 | } |
1128 | } |
1129 | } |
1130 | |
1131 | Datum |
1132 | tsqueryout(PG_FUNCTION_ARGS) |
1133 | { |
1134 | TSQuery query = PG_GETARG_TSQUERY(0); |
1135 | INFIX nrm; |
1136 | |
1137 | if (query->size == 0) |
1138 | { |
1139 | char *b = palloc(1); |
1140 | |
1141 | *b = '\0'; |
1142 | PG_RETURN_POINTER(b); |
1143 | } |
1144 | nrm.curpol = GETQUERY(query); |
1145 | nrm.buflen = 32; |
1146 | nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen); |
1147 | *(nrm.cur) = '\0'; |
1148 | nrm.op = GETOPERAND(query); |
1149 | infix(&nrm, -1 /* lowest priority */ , false); |
1150 | |
1151 | PG_FREE_IF_COPY(query, 0); |
1152 | PG_RETURN_CSTRING(nrm.buf); |
1153 | } |
1154 | |
1155 | /* |
1156 | * Binary Input / Output functions. The binary format is as follows: |
1157 | * |
1158 | * uint32 number of operators/operands in the query |
1159 | * |
1160 | * Followed by the operators and operands, in prefix notation. For each |
1161 | * operand: |
1162 | * |
1163 | * uint8 type, QI_VAL |
1164 | * uint8 weight |
1165 | * operand text in client encoding, null-terminated |
1166 | * uint8 prefix |
1167 | * |
1168 | * For each operator: |
1169 | * uint8 type, QI_OPR |
1170 | * uint8 operator, one of OP_AND, OP_PHRASE OP_OR, OP_NOT. |
1171 | * uint16 distance (only for OP_PHRASE) |
1172 | */ |
1173 | Datum |
1174 | tsquerysend(PG_FUNCTION_ARGS) |
1175 | { |
1176 | TSQuery query = PG_GETARG_TSQUERY(0); |
1177 | StringInfoData buf; |
1178 | int i; |
1179 | QueryItem *item = GETQUERY(query); |
1180 | |
1181 | pq_begintypsend(&buf); |
1182 | |
1183 | pq_sendint32(&buf, query->size); |
1184 | for (i = 0; i < query->size; i++) |
1185 | { |
1186 | pq_sendint8(&buf, item->type); |
1187 | |
1188 | switch (item->type) |
1189 | { |
1190 | case QI_VAL: |
1191 | pq_sendint8(&buf, item->qoperand.weight); |
1192 | pq_sendint8(&buf, item->qoperand.prefix); |
1193 | pq_sendstring(&buf, GETOPERAND(query) + item->qoperand.distance); |
1194 | break; |
1195 | case QI_OPR: |
1196 | pq_sendint8(&buf, item->qoperator.oper); |
1197 | if (item->qoperator.oper == OP_PHRASE) |
1198 | pq_sendint16(&buf, item->qoperator.distance); |
1199 | break; |
1200 | default: |
1201 | elog(ERROR, "unrecognized tsquery node type: %d" , item->type); |
1202 | } |
1203 | item++; |
1204 | } |
1205 | |
1206 | PG_FREE_IF_COPY(query, 0); |
1207 | |
1208 | PG_RETURN_BYTEA_P(pq_endtypsend(&buf)); |
1209 | } |
1210 | |
1211 | Datum |
1212 | tsqueryrecv(PG_FUNCTION_ARGS) |
1213 | { |
1214 | StringInfo buf = (StringInfo) PG_GETARG_POINTER(0); |
1215 | TSQuery query; |
1216 | int i, |
1217 | len; |
1218 | QueryItem *item; |
1219 | int datalen; |
1220 | char *ptr; |
1221 | uint32 size; |
1222 | const char **operands; |
1223 | bool needcleanup; |
1224 | |
1225 | size = pq_getmsgint(buf, sizeof(uint32)); |
1226 | if (size > (MaxAllocSize / sizeof(QueryItem))) |
1227 | elog(ERROR, "invalid size of tsquery" ); |
1228 | |
1229 | /* Allocate space to temporarily hold operand strings */ |
1230 | operands = palloc(size * sizeof(char *)); |
1231 | |
1232 | /* Allocate space for all the QueryItems. */ |
1233 | len = HDRSIZETQ + sizeof(QueryItem) * size; |
1234 | query = (TSQuery) palloc0(len); |
1235 | query->size = size; |
1236 | item = GETQUERY(query); |
1237 | |
1238 | datalen = 0; |
1239 | for (i = 0; i < size; i++) |
1240 | { |
1241 | item->type = (int8) pq_getmsgint(buf, sizeof(int8)); |
1242 | |
1243 | if (item->type == QI_VAL) |
1244 | { |
1245 | size_t val_len; /* length after recoding to server |
1246 | * encoding */ |
1247 | uint8 weight; |
1248 | uint8 prefix; |
1249 | const char *val; |
1250 | pg_crc32 valcrc; |
1251 | |
1252 | weight = (uint8) pq_getmsgint(buf, sizeof(uint8)); |
1253 | prefix = (uint8) pq_getmsgint(buf, sizeof(uint8)); |
1254 | val = pq_getmsgstring(buf); |
1255 | val_len = strlen(val); |
1256 | |
1257 | /* Sanity checks */ |
1258 | |
1259 | if (weight > 0xF) |
1260 | elog(ERROR, "invalid tsquery: invalid weight bitmap" ); |
1261 | |
1262 | if (val_len > MAXSTRLEN) |
1263 | elog(ERROR, "invalid tsquery: operand too long" ); |
1264 | |
1265 | if (datalen > MAXSTRPOS) |
1266 | elog(ERROR, "invalid tsquery: total operand length exceeded" ); |
1267 | |
1268 | /* Looks valid. */ |
1269 | |
1270 | INIT_LEGACY_CRC32(valcrc); |
1271 | COMP_LEGACY_CRC32(valcrc, val, val_len); |
1272 | FIN_LEGACY_CRC32(valcrc); |
1273 | |
1274 | item->qoperand.weight = weight; |
1275 | item->qoperand.prefix = (prefix) ? true : false; |
1276 | item->qoperand.valcrc = (int32) valcrc; |
1277 | item->qoperand.length = val_len; |
1278 | item->qoperand.distance = datalen; |
1279 | |
1280 | /* |
1281 | * Operand strings are copied to the final struct after this loop; |
1282 | * here we just collect them to an array |
1283 | */ |
1284 | operands[i] = val; |
1285 | |
1286 | datalen += val_len + 1; /* + 1 for the '\0' terminator */ |
1287 | } |
1288 | else if (item->type == QI_OPR) |
1289 | { |
1290 | int8 oper; |
1291 | |
1292 | oper = (int8) pq_getmsgint(buf, sizeof(int8)); |
1293 | if (oper != OP_NOT && oper != OP_OR && oper != OP_AND && oper != OP_PHRASE) |
1294 | elog(ERROR, "invalid tsquery: unrecognized operator type %d" , |
1295 | (int) oper); |
1296 | if (i == size - 1) |
1297 | elog(ERROR, "invalid pointer to right operand" ); |
1298 | |
1299 | item->qoperator.oper = oper; |
1300 | if (oper == OP_PHRASE) |
1301 | item->qoperator.distance = (int16) pq_getmsgint(buf, sizeof(int16)); |
1302 | } |
1303 | else |
1304 | elog(ERROR, "unrecognized tsquery node type: %d" , item->type); |
1305 | |
1306 | item++; |
1307 | } |
1308 | |
1309 | /* Enlarge buffer to make room for the operand values. */ |
1310 | query = (TSQuery) repalloc(query, len + datalen); |
1311 | item = GETQUERY(query); |
1312 | ptr = GETOPERAND(query); |
1313 | |
1314 | /* |
1315 | * Fill in the left-pointers. Checks that the tree is well-formed as a |
1316 | * side-effect. |
1317 | */ |
1318 | findoprnd(item, size, &needcleanup); |
1319 | |
1320 | /* Can't have found any QI_VALSTOP nodes */ |
1321 | Assert(!needcleanup); |
1322 | |
1323 | /* Copy operands to output struct */ |
1324 | for (i = 0; i < size; i++) |
1325 | { |
1326 | if (item->type == QI_VAL) |
1327 | { |
1328 | memcpy(ptr, operands[i], item->qoperand.length + 1); |
1329 | ptr += item->qoperand.length + 1; |
1330 | } |
1331 | item++; |
1332 | } |
1333 | |
1334 | pfree(operands); |
1335 | |
1336 | Assert(ptr - GETOPERAND(query) == datalen); |
1337 | |
1338 | SET_VARSIZE(query, len + datalen); |
1339 | |
1340 | PG_RETURN_TSQUERY(query); |
1341 | } |
1342 | |
1343 | /* |
1344 | * debug function, used only for view query |
1345 | * which will be executed in non-leaf pages in index |
1346 | */ |
1347 | Datum |
1348 | tsquerytree(PG_FUNCTION_ARGS) |
1349 | { |
1350 | TSQuery query = PG_GETARG_TSQUERY(0); |
1351 | INFIX nrm; |
1352 | text *res; |
1353 | QueryItem *q; |
1354 | int len; |
1355 | |
1356 | if (query->size == 0) |
1357 | { |
1358 | res = (text *) palloc(VARHDRSZ); |
1359 | SET_VARSIZE(res, VARHDRSZ); |
1360 | PG_RETURN_POINTER(res); |
1361 | } |
1362 | |
1363 | q = clean_NOT(GETQUERY(query), &len); |
1364 | |
1365 | if (!q) |
1366 | { |
1367 | res = cstring_to_text("T" ); |
1368 | } |
1369 | else |
1370 | { |
1371 | nrm.curpol = q; |
1372 | nrm.buflen = 32; |
1373 | nrm.cur = nrm.buf = (char *) palloc(sizeof(char) * nrm.buflen); |
1374 | *(nrm.cur) = '\0'; |
1375 | nrm.op = GETOPERAND(query); |
1376 | infix(&nrm, -1, false); |
1377 | res = cstring_to_text_with_len(nrm.buf, nrm.cur - nrm.buf); |
1378 | pfree(q); |
1379 | } |
1380 | |
1381 | PG_FREE_IF_COPY(query, 0); |
1382 | |
1383 | PG_RETURN_TEXT_P(res); |
1384 | } |
1385 | |