2 * Copyright (c) 1995, the EUROPAGATE consortium (see below).
4 * The EUROPAGATE consortium members are:
6 * University College Dublin
7 * Danmarks Teknologiske Videnscenter
8 * An Chomhairle Leabharlanna
9 * Consejo Superior de Investigaciones Cientificas
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12 * its documentation, in whole or in part, for any purpose, is hereby granted,
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47 * \brief Implements parsing of a CCL FIND query.
49 * This source file implements parsing of a CCL Query (ISO8777).
50 * The parser uses predictive parsing, but it does several tokens
51 * of lookahead in the handling of relational operations.. So
52 * it's not really pure.
56 /* CCL find (to rpn conversion)
59 * $Id: cclfind.c,v 1.10 2007-04-26 09:11:56 adam Exp $
63 * Revision 1.16 1996/01/08 08:41:13 adam
64 * Removed unused function.
66 * Revision 1.15 1995/07/20 08:14:34 adam
67 * Qualifiers were observed too often. Instead tokens are treated as
68 * qualifiers only when separated by comma.
70 * Revision 1.14 1995/05/16 09:39:26 adam
73 * Revision 1.13 1995/04/17 09:31:42 adam
74 * Improved handling of qualifiers. Aliases or reserved words.
76 * Revision 1.12 1995/03/20 15:27:43 adam
79 * Revision 1.11 1995/02/23 08:31:59 adam
82 * Revision 1.9 1995/02/16 13:20:06 adam
85 * Revision 1.8 1995/02/14 19:59:42 adam
86 * Removed a syntax error.
88 * Revision 1.7 1995/02/14 19:55:10 adam
89 * Header files ccl.h/cclp.h are gone! They have been merged an
90 * moved to ../include/ccl.h.
91 * Node kind(s) in ccl_rpn_node have changed names.
93 * Revision 1.6 1995/02/14 16:20:55 adam
94 * Qualifiers are read from a file now.
96 * Revision 1.5 1995/02/14 14:12:41 adam
97 * Ranges for ordered qualfiers implemented (e.g. pd=1980-1990).
99 * Revision 1.4 1995/02/14 13:16:29 adam
100 * Left and/or right truncation implemented.
102 * Revision 1.3 1995/02/14 10:25:56 adam
103 * The constructions 'qualifier rel term ...' implemented.
105 * Revision 1.2 1995/02/13 15:15:07 adam
106 * Added handling of qualifiers. Not finished yet.
108 * Revision 1.1 1995/02/13 12:35:20 adam
109 * First version of CCL. Qualifiers aren't handled yet.
118 /* returns type of current lookahead */
119 #define KIND (cclp->look_token->kind)
121 /* move one token forward */
122 #define ADVANCE cclp->look_token = cclp->look_token->next
125 * qual_val_type: test for existance of attribute type/value pair.
126 * qa: Attribute array
127 * type: Type of attribute to search for
128 * value: Value of attribute to seach for
129 * return: 1 if found; 0 otherwise.
131 static int qual_val_type (struct ccl_rpn_attr **qa, int type, int value,
135 struct ccl_rpn_attr *q;
139 for (i = 0; (q=qa[i]); i++)
142 if (q->type == type && q->kind == CCL_RPN_ATTR_NUMERIC &&
143 q->value.numeric == value)
155 * strxcat: concatenate strings.
156 * n: Null-terminated Destination string
157 * src: Source string to be appended (not null-terminated)
158 * len: Length of source string.
160 static void strxcat (char *n, const char *src, int len)
170 * copy_token_name: Return copy of CCL token name
171 * tp: Pointer to token info.
172 * return: malloc(3) allocated copy of token name.
174 static char *copy_token_name (struct ccl_token *tp)
176 char *str = (char *)xmalloc (tp->len + 1);
178 memcpy (str, tp->name, tp->len);
184 * mk_node: Create RPN node.
185 * kind: Type of node.
186 * return: pointer to allocated node.
188 static struct ccl_rpn_node *mk_node (int kind)
190 struct ccl_rpn_node *p;
191 p = (struct ccl_rpn_node *)xmalloc (sizeof(*p));
198 * ccl_rpn_delete: Delete RPN tree.
199 * rpn: Pointer to tree.
201 void ccl_rpn_delete (struct ccl_rpn_node *rpn)
203 struct ccl_rpn_attr *attr, *attr1;
211 ccl_rpn_delete (rpn->u.p[0]);
212 ccl_rpn_delete (rpn->u.p[1]);
215 xfree (rpn->u.t.term);
216 for (attr = rpn->u.t.attr_list; attr; attr = attr1)
219 if (attr->kind == CCL_RPN_ATTR_STRING)
220 xfree(attr->value.str);
227 xfree (rpn->u.setname);
230 ccl_rpn_delete (rpn->u.p[0]);
231 ccl_rpn_delete (rpn->u.p[1]);
232 ccl_rpn_delete (rpn->u.p[2]);
238 static struct ccl_rpn_node *find_spec (CCL_parser cclp,
239 struct ccl_rpn_attr **qa);
241 static int is_term_ok (int look, int *list)
243 for (;*list >= 0; list++)
249 static struct ccl_rpn_node *search_terms (CCL_parser cclp,
250 struct ccl_rpn_attr **qa);
252 static struct ccl_rpn_attr *add_attr_node (struct ccl_rpn_node *p,
253 const char *set, int type)
255 struct ccl_rpn_attr *n;
257 n = (struct ccl_rpn_attr *)xmalloc (sizeof(*n));
260 n->set = xstrdup(set);
264 n->next = p->u.t.attr_list;
265 p->u.t.attr_list = n;
267 n->kind = CCL_RPN_ATTR_NUMERIC;
268 n->value.numeric = 0;
273 * add_attr_numeric: Add attribute (type/value) to RPN term node.
274 * p: RPN node of type term.
275 * type: Type of attribute
276 * value: Value of attribute
277 * set: Attribute set name
279 static void add_attr_numeric (struct ccl_rpn_node *p, const char *set,
282 struct ccl_rpn_attr *n;
284 n = add_attr_node(p, set, type);
285 n->kind = CCL_RPN_ATTR_NUMERIC;
286 n->value.numeric = value;
289 static void add_attr_string (struct ccl_rpn_node *p, const char *set,
290 int type, char *value)
292 struct ccl_rpn_attr *n;
294 n = add_attr_node(p, set, type);
295 n->kind = CCL_RPN_ATTR_STRING;
296 n->value.str = xstrdup(value);
301 * search_term: Parse CCL search term.
303 * qa: Qualifier attributes already applied.
304 * term_list: tokens we accept as terms in context
305 * multi: whether we accept "multiple" tokens
306 * return: pointer to node(s); NULL on error.
308 static struct ccl_rpn_node *search_term_x (CCL_parser cclp,
309 struct ccl_rpn_attr **qa,
310 int *term_list, int multi)
312 struct ccl_rpn_node *p_top = 0;
313 struct ccl_token *lookahead = cclp->look_token;
317 const char *truncation_aliases;
320 ccl_qual_search_special(cclp->bibset, "truncation");
321 if (!truncation_aliases)
322 truncation_aliases = "?";
324 if (qual_val_type (qa, CCL_BIB1_STR, CCL_BIB1_STR_AND_LIST, 0))
326 if (qual_val_type (qa, CCL_BIB1_STR, CCL_BIB1_STR_OR_LIST, 0))
330 struct ccl_rpn_node *p;
336 int relation_value = -1;
337 int position_value = -1;
338 int structure_value = -1;
339 int truncation_value = -1;
340 int completeness_value = -1;
343 if (and_list || or_list || !multi)
346 /* ignore commas when dealing with and-lists .. */
347 if (and_list && lookahead && lookahead->kind == CCL_TOK_COMMA)
349 lookahead = lookahead->next;
353 /* go through each TERM token. If no truncation attribute is yet
354 met, then look for left/right truncation markers (?) and
355 set left_trunc/right_trunc/mid_trunc accordingly */
356 for (no = 0; no < max && is_term_ok(lookahead->kind, term_list); no++)
358 for (i = 0; i<lookahead->len; i++)
359 if (lookahead->name[i] == ' ')
361 else if (strchr(truncation_aliases, lookahead->name[i]))
363 if (no == 0 && i == 0 && lookahead->len >= 1)
365 else if (!is_term_ok(lookahead->next->kind, term_list) &&
366 i == lookahead->len-1 && i >= 1)
371 len += 1+lookahead->len+lookahead->ws_prefix_len;
372 lookahead = lookahead->next;
376 break; /* no more terms . stop . */
382 p = mk_node (CCL_RPN_OR);
384 p = mk_node (CCL_RPN_AND);
386 p = mk_node (CCL_RPN_AND);
391 /* create the term node, but wait a moment before adding the term */
392 p = mk_node (CCL_RPN_TERM);
393 p->u.t.attr_list = NULL;
396 /* make the top node point to us.. */
403 /* go through all attributes and add them to the attribute list */
404 for (i=0; qa && qa[i]; i++)
406 struct ccl_rpn_attr *attr;
408 for (attr = qa[i]; attr; attr = attr->next)
411 case CCL_RPN_ATTR_STRING:
412 add_attr_string(p, attr->set, attr->type,
415 case CCL_RPN_ATTR_NUMERIC:
416 if (attr->value.numeric > 0)
417 { /* deal only with REAL attributes (positive) */
421 if (relation_value != -1)
423 relation_value = attr->value.numeric;
426 if (position_value != -1)
428 position_value = attr->value.numeric;
431 if (structure_value != -1)
433 structure_value = attr->value.numeric;
436 if (truncation_value != -1)
438 truncation_value = attr->value.numeric;
439 left_trunc = right_trunc = mid_trunc = 0;
442 if (completeness_value != -1)
444 completeness_value = attr->value.numeric;
447 add_attr_numeric(p, attr->set, attr->type,
448 attr->value.numeric);
452 /* len now holds the number of characters in the RPN term */
453 /* no holds the number of CCL tokens (1 or more) */
455 if (structure_value == -1 &&
456 qual_val_type (qa, CCL_BIB1_STR, CCL_BIB1_STR_WP, &attset))
457 { /* no structure attribute met. Apply either structure attribute
458 WORD or PHRASE depending on number of CCL tokens */
459 if (no == 1 && no_spaces == 0)
460 add_attr_numeric (p, attset, CCL_BIB1_STR, 2);
462 add_attr_numeric (p, attset, CCL_BIB1_STR, 1);
465 /* make the RPN token */
466 p->u.t.term = (char *)xmalloc (len);
467 ccl_assert (p->u.t.term);
468 p->u.t.term[0] = '\0';
469 for (i = 0; i<no; i++)
471 const char *src_str = cclp->look_token->name;
472 int src_len = cclp->look_token->len;
474 if (i == 0 && left_trunc)
479 if (i == no-1 && right_trunc)
481 if (i && cclp->look_token->ws_prefix_len)
483 size_t len = strlen(p->u.t.term);
484 memcpy(p->u.t.term + len, cclp->look_token->ws_prefix_buf,
485 cclp->look_token->ws_prefix_len);
486 p->u.t.term[len + cclp->look_token->ws_prefix_len] = '\0';
488 strxcat (p->u.t.term, src_str, src_len);
491 if (left_trunc && right_trunc)
493 if (!qual_val_type (qa, CCL_BIB1_TRU, CCL_BIB1_TRU_CAN_BOTH,
496 cclp->error_code = CCL_ERR_TRUNC_NOT_BOTH;
500 add_attr_numeric (p, attset, CCL_BIB1_TRU, 3);
502 else if (right_trunc)
504 if (!qual_val_type (qa, CCL_BIB1_TRU, CCL_BIB1_TRU_CAN_RIGHT,
507 cclp->error_code = CCL_ERR_TRUNC_NOT_RIGHT;
511 add_attr_numeric (p, attset, CCL_BIB1_TRU, 1);
515 if (!qual_val_type (qa, CCL_BIB1_TRU, CCL_BIB1_TRU_CAN_LEFT,
518 cclp->error_code = CCL_ERR_TRUNC_NOT_LEFT;
522 add_attr_numeric (p, attset, CCL_BIB1_TRU, 2);
526 if (qual_val_type (qa, CCL_BIB1_TRU, CCL_BIB1_TRU_CAN_NONE,
528 add_attr_numeric (p, attset, CCL_BIB1_TRU, 100);
534 cclp->error_code = CCL_ERR_TERM_EXPECTED;
538 static struct ccl_rpn_node *search_term (CCL_parser cclp,
539 struct ccl_rpn_attr **qa)
541 static int list[] = {CCL_TOK_TERM, CCL_TOK_COMMA, -1};
542 return search_term_x(cclp, qa, list, 0);
546 struct ccl_rpn_node *qualifiers_order (CCL_parser cclp,
547 struct ccl_rpn_attr **ap, char *attset)
550 struct ccl_rpn_node *p;
552 if (cclp->look_token->len == 1)
554 if (cclp->look_token->name[0] == '<')
556 else if (cclp->look_token->name[0] == '=')
558 else if (cclp->look_token->name[0] == '>')
561 else if (cclp->look_token->len == 2)
563 if (!memcmp (cclp->look_token->name, "<=", 2))
565 else if (!memcmp (cclp->look_token->name, ">=", 2))
567 else if (!memcmp (cclp->look_token->name, "<>", 2))
572 cclp->error_code = CCL_ERR_BAD_RELATION;
575 ADVANCE; /* skip relation */
577 qual_val_type(ap, CCL_BIB1_REL, CCL_BIB1_REL_PORDER, 0))
579 /* allow - inside term and treat it as range _always_ */
580 /* relation is =. Extract "embedded" - to separate terms */
581 if (KIND == CCL_TOK_TERM)
584 for (i = 0; i<cclp->look_token->len; i++)
586 if (cclp->look_token->name[i] == '-')
590 if (cclp->look_token->len > 1 && i == 0)
592 struct ccl_token *ntoken = ccl_token_add (cclp->look_token);
594 ntoken->kind = CCL_TOK_TERM;
595 ntoken->name = cclp->look_token->name + 1;
596 ntoken->len = cclp->look_token->len - 1;
598 cclp->look_token->len = 1;
599 cclp->look_token->name = "-";
601 else if (cclp->look_token->len > 1 && i == cclp->look_token->len-1)
603 struct ccl_token *ntoken = ccl_token_add (cclp->look_token);
605 ntoken->kind = CCL_TOK_TERM;
609 (cclp->look_token->len)--;
611 else if (cclp->look_token->len > 2 && i < cclp->look_token->len)
613 struct ccl_token *ntoken1 = ccl_token_add (cclp->look_token);
614 struct ccl_token *ntoken2 = ccl_token_add (ntoken1);
616 ntoken1->kind = CCL_TOK_TERM; /* generate - */
620 ntoken2->kind = CCL_TOK_TERM; /* generate yy */
621 ntoken2->name = cclp->look_token->name + (i+1);
622 ntoken2->len = cclp->look_token->len - (i+1);
624 cclp->look_token->len = i; /* adjust xx */
626 else if (i == cclp->look_token->len &&
627 cclp->look_token->next &&
628 cclp->look_token->next->kind == CCL_TOK_TERM &&
629 cclp->look_token->next->len > 1 &&
630 cclp->look_token->next->name[0] == '-')
633 /* we _know_ that xx does not have - in it */
634 struct ccl_token *ntoken = ccl_token_add (cclp->look_token);
636 ntoken->kind = CCL_TOK_TERM; /* generate - */
640 (ntoken->next->name)++; /* adjust yy */
641 (ntoken->next->len)--;
647 KIND == CCL_TOK_TERM &&
648 cclp->look_token->next && cclp->look_token->next->len == 1 &&
649 cclp->look_token->next->name[0] == '-')
651 struct ccl_rpn_node *p1;
652 if (!(p1 = search_term (cclp, ap)))
654 ADVANCE; /* skip '-' */
655 if (KIND == CCL_TOK_TERM) /* = term - term ? */
657 struct ccl_rpn_node *p2;
659 if (!(p2 = search_term (cclp, ap)))
664 p = mk_node (CCL_RPN_AND);
666 add_attr_numeric (p1, attset, CCL_BIB1_REL, 4);
668 add_attr_numeric (p2, attset, CCL_BIB1_REL, 2);
673 add_attr_numeric (p1, attset, CCL_BIB1_REL, 4);
678 cclp->look_token->len == 1 &&
679 cclp->look_token->name[0] == '-') /* = - term ? */
682 if (!(p = search_term (cclp, ap)))
684 add_attr_numeric (p, attset, CCL_BIB1_REL, 2);
687 else if (KIND == CCL_TOK_LP)
690 if (!(p = find_spec (cclp, ap)))
692 if (KIND != CCL_TOK_RP)
694 cclp->error_code = CCL_ERR_RP_EXPECTED;
703 if (!(p = search_terms (cclp, ap)))
705 add_attr_numeric (p, attset, CCL_BIB1_REL, rel);
708 cclp->error_code = CCL_ERR_TERM_EXPECTED;
713 struct ccl_rpn_node *qualifiers2 (CCL_parser cclp, struct ccl_rpn_attr **ap)
716 struct ccl_rpn_node *p;
718 if (qual_val_type(ap, CCL_BIB1_REL, CCL_BIB1_REL_ORDER, &attset)
719 || qual_val_type(ap, CCL_BIB1_REL, CCL_BIB1_REL_PORDER, &attset))
720 return qualifiers_order(cclp, ap, attset);
722 /* unordered relation */
723 if (KIND != CCL_TOK_EQ)
725 cclp->error_code = CCL_ERR_EQ_EXPECTED;
729 if (KIND == CCL_TOK_LP)
732 if (!(p = find_spec (cclp, ap)))
736 if (KIND != CCL_TOK_RP)
738 cclp->error_code = CCL_ERR_RP_EXPECTED;
745 p = search_terms (cclp, ap);
750 * qualifiers1: Parse CCL qualifiers and search terms.
752 * la: Token pointer to RELATION token.
753 * qa: Qualifier attributes already applied.
754 * return: pointer to node(s); NULL on error.
756 static struct ccl_rpn_node *qualifiers1 (CCL_parser cclp, struct ccl_token *la,
757 struct ccl_rpn_attr **qa)
759 struct ccl_token *lookahead = cclp->look_token;
760 struct ccl_token *look_start = cclp->look_token;
761 struct ccl_rpn_attr **ap;
762 struct ccl_rpn_node *node = 0;
763 const char *field_str;
771 cclp->error_code = CCL_ERR_DOUBLE_QUAL;
775 for (lookahead = cclp->look_token; lookahead != la;
776 lookahead=lookahead->next)
779 for (i=0; qa[i]; i++)
781 ap = (struct ccl_rpn_attr **)xmalloc ((no ? (no+1) : 2) * sizeof(*ap));
784 field_str = ccl_qual_search_special(cclp->bibset, "field");
787 if (!strcmp (field_str, "or"))
789 else if (!strcmp (field_str, "merge"))
794 /* consider each field separately and OR */
795 lookahead = look_start;
796 while (lookahead != la)
800 while ((ap[0] = ccl_qual_search (cclp, lookahead->name,
801 lookahead->len, seq)) != 0)
803 struct ccl_rpn_node *node_sub;
804 cclp->look_token = la;
806 node_sub = qualifiers2(cclp, ap);
809 ccl_rpn_delete (node);
815 struct ccl_rpn_node *node_this = mk_node(CCL_RPN_OR);
816 node_this->u.p[0] = node;
817 node_this->u.p[1] = node_sub;
826 cclp->look_token = lookahead;
827 cclp->error_code = CCL_ERR_UNKNOWN_QUAL;
831 lookahead = lookahead->next;
832 if (lookahead->kind == CCL_TOK_COMMA)
833 lookahead = lookahead->next;
838 /* merge attributes from ALL fields - including inherited ones */
841 struct ccl_rpn_node *node_sub;
843 lookahead = look_start;
844 for (i = 0; lookahead != la; i++)
846 ap[i] = ccl_qual_search (cclp, lookahead->name,
847 lookahead->len, seq);
850 if (!ap[i] && seq > 0)
851 ap[i] = ccl_qual_search (cclp, lookahead->name,
855 cclp->look_token = lookahead;
856 cclp->error_code = CCL_ERR_UNKNOWN_QUAL;
860 lookahead = lookahead->next;
861 if (lookahead->kind == CCL_TOK_COMMA)
862 lookahead = lookahead->next;
866 struct ccl_rpn_attr **qa0 = qa;
876 cclp->look_token = lookahead;
878 node_sub = qualifiers2(cclp, ap);
881 ccl_rpn_delete (node);
886 struct ccl_rpn_node *node_this = mk_node(CCL_RPN_OR);
887 node_this->u.p[0] = node;
888 node_this->u.p[1] = node_sub;
902 * search_terms: Parse CCL search terms - including proximity.
904 * qa: Qualifier attributes already applied.
905 * return: pointer to node(s); NULL on error.
907 static struct ccl_rpn_node *search_terms (CCL_parser cclp,
908 struct ccl_rpn_attr **qa)
910 static int list[] = {
911 CCL_TOK_TERM, CCL_TOK_COMMA,CCL_TOK_EQ, CCL_TOK_REL, CCL_TOK_SET, -1};
912 struct ccl_rpn_node *p1, *p2, *pn;
913 p1 = search_term_x (cclp, qa, list, 1);
918 if (KIND == CCL_TOK_PROX)
920 struct ccl_rpn_node *p_prox = 0;
921 /* ! word order specified */
922 /* % word order not specified */
923 p_prox = mk_node(CCL_RPN_TERM);
924 p_prox->u.t.term = (char *) xmalloc(1 + cclp->look_token->len);
925 memcpy(p_prox->u.t.term, cclp->look_token->name,
926 cclp->look_token->len);
927 p_prox->u.t.term[cclp->look_token->len] = 0;
928 p_prox->u.t.attr_list = 0;
931 p2 = search_term_x (cclp, qa, list, 1);
937 pn = mk_node (CCL_RPN_PROX);
943 else if (is_term_ok(KIND, list))
945 p2 = search_term_x (cclp, qa, list, 1);
951 pn = mk_node (CCL_RPN_PROX);
964 * search_elements: Parse CCL search elements
966 * qa: Qualifier attributes already applied.
967 * return: pointer to node(s); NULL on error.
969 static struct ccl_rpn_node *search_elements (CCL_parser cclp,
970 struct ccl_rpn_attr **qa)
972 struct ccl_rpn_node *p1;
973 struct ccl_token *lookahead;
974 if (KIND == CCL_TOK_LP)
977 p1 = find_spec (cclp, qa);
980 if (KIND != CCL_TOK_RP)
982 cclp->error_code = CCL_ERR_RP_EXPECTED;
989 else if (KIND == CCL_TOK_SET)
992 if (KIND == CCL_TOK_EQ)
994 if (KIND != CCL_TOK_TERM)
996 cclp->error_code = CCL_ERR_SETNAME_EXPECTED;
999 p1 = mk_node (CCL_RPN_SET);
1000 p1->u.setname = copy_token_name (cclp->look_token);
1004 lookahead = cclp->look_token;
1006 while (lookahead->kind==CCL_TOK_TERM)
1008 lookahead = lookahead->next;
1009 if (lookahead->kind == CCL_TOK_REL || lookahead->kind == CCL_TOK_EQ)
1010 return qualifiers1 (cclp, lookahead, qa);
1011 if (lookahead->kind != CCL_TOK_COMMA)
1013 lookahead = lookahead->next;
1016 return search_terms (cclp, qa);
1019 struct ccl_rpn_attr *qa[2];
1020 struct ccl_rpn_node *node = 0;
1022 lookahead = cclp->look_token;
1025 for(seq = 0; ;seq++)
1027 struct ccl_rpn_node *node_sub;
1028 qa[0] = ccl_qual_search(cclp, "term", 4, seq);
1032 cclp->look_token = lookahead;
1034 node_sub = search_terms (cclp, qa);
1037 ccl_rpn_delete (node);
1042 struct ccl_rpn_node *node_this = mk_node(CCL_RPN_OR);
1043 node_this->u.p[0] = node;
1044 node_this->u.p[1] = node_sub;
1045 node_this->u.p[2] = 0;
1052 node = search_terms (cclp, 0);
1058 * find_spec: Parse CCL find specification
1060 * qa: Qualifier attributes already applied.
1061 * return: pointer to node(s); NULL on error.
1063 static struct ccl_rpn_node *find_spec (CCL_parser cclp,
1064 struct ccl_rpn_attr **qa)
1066 struct ccl_rpn_node *p1, *p2, *pn;
1067 if (!(p1 = search_elements (cclp, qa)))
1075 p2 = search_elements (cclp, qa);
1078 ccl_rpn_delete (p1);
1081 pn = mk_node (CCL_RPN_AND);
1089 p2 = search_elements (cclp, qa);
1092 ccl_rpn_delete (p1);
1095 pn = mk_node (CCL_RPN_OR);
1103 p2 = search_elements (cclp, qa);
1106 ccl_rpn_delete (p1);
1109 pn = mk_node (CCL_RPN_NOT);
1121 struct ccl_rpn_node *ccl_parser_find_str(CCL_parser cclp, const char *str)
1123 struct ccl_rpn_node *p;
1124 struct ccl_token *list = ccl_parser_tokenize(cclp, str);
1125 p = ccl_parser_find_token(cclp, list);
1126 ccl_token_del(list);
1130 struct ccl_rpn_node *ccl_parser_find_token(CCL_parser cclp,
1131 struct ccl_token *list)
1133 struct ccl_rpn_node *p;
1135 cclp->look_token = list;
1136 p = find_spec (cclp, NULL);
1137 if (p && KIND != CCL_TOK_EOL)
1139 if (KIND == CCL_TOK_RP)
1140 cclp->error_code = CCL_ERR_BAD_RP;
1142 cclp->error_code = CCL_ERR_OP_EXPECTED;
1146 cclp->error_pos = cclp->look_token->name;
1148 cclp->error_code = CCL_ERR_OK;
1150 cclp->error_code = cclp->error_code;
1155 * ccl_find_str: Parse CCL find - string representation
1156 * bibset: Bibset to be used for the parsing
1157 * str: String to be parsed
1158 * error: Pointer to integer. Holds error no. on completion.
1159 * pos: Pointer to char position. Holds approximate error position.
1160 * return: RPN tree on successful completion; NULL otherwise.
1162 struct ccl_rpn_node *ccl_find_str(CCL_bibset bibset, const char *str,
1163 int *error, int *pos)
1165 CCL_parser cclp = ccl_parser_create (bibset);
1166 struct ccl_token *list;
1167 struct ccl_rpn_node *p;
1169 list = ccl_parser_tokenize (cclp, str);
1170 p = ccl_parser_find_token(cclp, list);
1172 *error = cclp->error_code;
1174 *pos = cclp->error_pos - str;
1175 ccl_parser_destroy (cclp);
1176 ccl_token_del (list);
1182 * indent-tabs-mode: nil
1184 * vim: shiftwidth=4 tabstop=8 expandtab