1 /*
2 * regexp.c: generic and extensible Regular Expression engine
3 *
4 * Basically designed with the purpose of compiling regexps for
5 * the variety of validation/shemas mechanisms now available in
6 * XML related specifications these include:
7 * - XML-1.0 DTD validation
8 * - XML Schemas structure part 1
9 * - XML Schemas Datatypes part 2 especially Appendix F
10 * - RELAX-NG/TREX i.e. the counter proposal
11 *
12 * See Copyright for the status of this software.
13 *
14 * Daniel Veillard <veillard@redhat.com>
15 */
16
17 #define IN_LIBXML
18 #include "libxml.h"
19
20 #ifdef LIBXML_REGEXP_ENABLED
21
22 /* #define DEBUG_ERR */
23
24 #include <stdio.h>
25 #include <string.h>
26 #ifdef HAVE_LIMITS_H
27 #include <limits.h>
28 #endif
29
30 #include <libxml/tree.h>
31 #include <libxml/parserInternals.h>
32 #include <libxml/xmlregexp.h>
33 #include <libxml/xmlautomata.h>
34 #include <libxml/xmlunicode.h>
35
36 #ifndef INT_MAX
37 #define INT_MAX 123456789 /* easy to flag and big enough for our needs */
38 #endif
39
40 /* #define DEBUG_REGEXP_GRAPH */
41 /* #define DEBUG_REGEXP_EXEC */
42 /* #define DEBUG_PUSH */
43 /* #define DEBUG_COMPACTION */
44
45 #define MAX_PUSH 10000000
46
47 #define ERROR(str) \
48 ctxt->error = XML_REGEXP_COMPILE_ERROR; \
49 xmlRegexpErrCompile(ctxt, str);
50 #define NEXT ctxt->cur++
51 #define CUR (*(ctxt->cur))
52 #define NXT(index) (ctxt->cur[index])
53
54 #define CUR_SCHAR(s, l) xmlStringCurrentChar(NULL, s, &l)
55 #define NEXTL(l) ctxt->cur += l;
56 #define XML_REG_STRING_SEPARATOR '|'
57 /*
58 * Need PREV to check on a '-' within a Character Group. May only be used
59 * when it's guaranteed that cur is not at the beginning of ctxt->string!
60 */
61 #define PREV (ctxt->cur[-1])
62
63 /**
64 * TODO:
65 *
66 * macro to flag unimplemented blocks
67 */
68 #define TODO \
69 xmlGenericError(xmlGenericErrorContext, \
70 "Unimplemented block at %s:%d\n", \
71 __FILE__, __LINE__);
72
73 /************************************************************************
74 * *
75 * Datatypes and structures *
76 * *
77 ************************************************************************/
78
79 /*
80 * Note: the order of the enums below is significant, do not shuffle
81 */
82 typedef enum {
83 XML_REGEXP_EPSILON = 1,
84 XML_REGEXP_CHARVAL,
85 XML_REGEXP_RANGES,
86 XML_REGEXP_SUBREG, /* used for () sub regexps */
87 XML_REGEXP_STRING,
88 XML_REGEXP_ANYCHAR, /* . */
89 XML_REGEXP_ANYSPACE, /* \s */
90 XML_REGEXP_NOTSPACE, /* \S */
91 XML_REGEXP_INITNAME, /* \l */
92 XML_REGEXP_NOTINITNAME, /* \L */
93 XML_REGEXP_NAMECHAR, /* \c */
94 XML_REGEXP_NOTNAMECHAR, /* \C */
95 XML_REGEXP_DECIMAL, /* \d */
96 XML_REGEXP_NOTDECIMAL, /* \D */
97 XML_REGEXP_REALCHAR, /* \w */
98 XML_REGEXP_NOTREALCHAR, /* \W */
99 XML_REGEXP_LETTER = 100,
100 XML_REGEXP_LETTER_UPPERCASE,
101 XML_REGEXP_LETTER_LOWERCASE,
102 XML_REGEXP_LETTER_TITLECASE,
103 XML_REGEXP_LETTER_MODIFIER,
104 XML_REGEXP_LETTER_OTHERS,
105 XML_REGEXP_MARK,
106 XML_REGEXP_MARK_NONSPACING,
107 XML_REGEXP_MARK_SPACECOMBINING,
108 XML_REGEXP_MARK_ENCLOSING,
109 XML_REGEXP_NUMBER,
110 XML_REGEXP_NUMBER_DECIMAL,
111 XML_REGEXP_NUMBER_LETTER,
112 XML_REGEXP_NUMBER_OTHERS,
113 XML_REGEXP_PUNCT,
114 XML_REGEXP_PUNCT_CONNECTOR,
115 XML_REGEXP_PUNCT_DASH,
116 XML_REGEXP_PUNCT_OPEN,
117 XML_REGEXP_PUNCT_CLOSE,
118 XML_REGEXP_PUNCT_INITQUOTE,
119 XML_REGEXP_PUNCT_FINQUOTE,
120 XML_REGEXP_PUNCT_OTHERS,
121 XML_REGEXP_SEPAR,
122 XML_REGEXP_SEPAR_SPACE,
123 XML_REGEXP_SEPAR_LINE,
124 XML_REGEXP_SEPAR_PARA,
125 XML_REGEXP_SYMBOL,
126 XML_REGEXP_SYMBOL_MATH,
127 XML_REGEXP_SYMBOL_CURRENCY,
128 XML_REGEXP_SYMBOL_MODIFIER,
129 XML_REGEXP_SYMBOL_OTHERS,
130 XML_REGEXP_OTHER,
131 XML_REGEXP_OTHER_CONTROL,
132 XML_REGEXP_OTHER_FORMAT,
133 XML_REGEXP_OTHER_PRIVATE,
134 XML_REGEXP_OTHER_NA,
135 XML_REGEXP_BLOCK_NAME
136 } xmlRegAtomType;
137
138 typedef enum {
139 XML_REGEXP_QUANT_EPSILON = 1,
140 XML_REGEXP_QUANT_ONCE,
141 XML_REGEXP_QUANT_OPT,
142 XML_REGEXP_QUANT_MULT,
143 XML_REGEXP_QUANT_PLUS,
144 XML_REGEXP_QUANT_ONCEONLY,
145 XML_REGEXP_QUANT_ALL,
146 XML_REGEXP_QUANT_RANGE
147 } xmlRegQuantType;
148
149 typedef enum {
150 XML_REGEXP_START_STATE = 1,
151 XML_REGEXP_FINAL_STATE,
152 XML_REGEXP_TRANS_STATE,
153 XML_REGEXP_SINK_STATE,
154 XML_REGEXP_UNREACH_STATE
155 } xmlRegStateType;
156
157 typedef enum {
158 XML_REGEXP_MARK_NORMAL = 0,
159 XML_REGEXP_MARK_START,
160 XML_REGEXP_MARK_VISITED
161 } xmlRegMarkedType;
162
163 typedef struct _xmlRegRange xmlRegRange;
164 typedef xmlRegRange *xmlRegRangePtr;
165
166 struct _xmlRegRange {
167 int neg; /* 0 normal, 1 not, 2 exclude */
168 xmlRegAtomType type;
169 int start;
170 int end;
171 xmlChar *blockName;
172 };
173
174 typedef struct _xmlRegAtom xmlRegAtom;
175 typedef xmlRegAtom *xmlRegAtomPtr;
176
177 typedef struct _xmlAutomataState xmlRegState;
178 typedef xmlRegState *xmlRegStatePtr;
179
180 struct _xmlRegAtom {
181 int no;
182 xmlRegAtomType type;
183 xmlRegQuantType quant;
184 int min;
185 int max;
186
187 void *valuep;
188 void *valuep2;
189 int neg;
190 int codepoint;
191 xmlRegStatePtr start;
192 xmlRegStatePtr start0;
193 xmlRegStatePtr stop;
194 int maxRanges;
195 int nbRanges;
196 xmlRegRangePtr *ranges;
197 void *data;
198 };
199
200 typedef struct _xmlRegCounter xmlRegCounter;
201 typedef xmlRegCounter *xmlRegCounterPtr;
202
203 struct _xmlRegCounter {
204 int min;
205 int max;
206 };
207
208 typedef struct _xmlRegTrans xmlRegTrans;
209 typedef xmlRegTrans *xmlRegTransPtr;
210
211 struct _xmlRegTrans {
212 xmlRegAtomPtr atom;
213 int to;
214 int counter;
215 int count;
216 int nd;
217 };
218
219 struct _xmlAutomataState {
220 xmlRegStateType type;
221 xmlRegMarkedType mark;
222 xmlRegMarkedType reached;
223 int no;
224 int maxTrans;
225 int nbTrans;
226 xmlRegTrans *trans;
227 /* knowing states ponting to us can speed things up */
228 int maxTransTo;
229 int nbTransTo;
230 int *transTo;
231 };
232
233 typedef struct _xmlAutomata xmlRegParserCtxt;
234 typedef xmlRegParserCtxt *xmlRegParserCtxtPtr;
235
236 struct _xmlAutomata {
237 xmlChar *string;
238 xmlChar *cur;
239
240 int error;
241 int neg;
242
243 xmlRegStatePtr start;
244 xmlRegStatePtr end;
245 xmlRegStatePtr state;
246
247 xmlRegAtomPtr atom;
248
249 int maxAtoms;
250 int nbAtoms;
251 xmlRegAtomPtr *atoms;
252
253 int maxStates;
254 int nbStates;
255 xmlRegStatePtr *states;
256
257 int maxCounters;
258 int nbCounters;
259 xmlRegCounter *counters;
260
261 int determinist;
262 int negs;
263 };
264
265 struct _xmlRegexp {
266 xmlChar *string;
267 int nbStates;
268 xmlRegStatePtr *states;
269 int nbAtoms;
270 xmlRegAtomPtr *atoms;
271 int nbCounters;
272 xmlRegCounter *counters;
273 int determinist;
274 /*
275 * That's the compact form for determinists automatas
276 */
277 int nbstates;
278 int *compact;
279 void **transdata;
280 int nbstrings;
281 xmlChar **stringMap;
282 };
283
284 typedef struct _xmlRegExecRollback xmlRegExecRollback;
285 typedef xmlRegExecRollback *xmlRegExecRollbackPtr;
286
287 struct _xmlRegExecRollback {
288 xmlRegStatePtr state;/* the current state */
289 int index; /* the index in the input stack */
290 int nextbranch; /* the next transition to explore in that state */
291 int *counts; /* save the automata state if it has some */
292 };
293
294 typedef struct _xmlRegInputToken xmlRegInputToken;
295 typedef xmlRegInputToken *xmlRegInputTokenPtr;
296
297 struct _xmlRegInputToken {
298 xmlChar *value;
299 void *data;
300 };
301
302 struct _xmlRegExecCtxt {
303 int status; /* execution status != 0 indicate an error */
304 int determinist; /* did we find an indeterministic behaviour */
305 xmlRegexpPtr comp; /* the compiled regexp */
306 xmlRegExecCallbacks callback;
307 void *data;
308
309 xmlRegStatePtr state;/* the current state */
310 int transno; /* the current transition on that state */
311 int transcount; /* the number of chars in char counted transitions */
312
313 /*
314 * A stack of rollback states
315 */
316 int maxRollbacks;
317 int nbRollbacks;
318 xmlRegExecRollback *rollbacks;
319
320 /*
321 * The state of the automata if any
322 */
323 int *counts;
324
325 /*
326 * The input stack
327 */
328 int inputStackMax;
329 int inputStackNr;
330 int index;
331 int *charStack;
332 const xmlChar *inputString; /* when operating on characters */
333 xmlRegInputTokenPtr inputStack;/* when operating on strings */
334
335 /*
336 * error handling
337 */
338 int errStateNo; /* the error state number */
339 xmlRegStatePtr errState; /* the error state */
340 xmlChar *errString; /* the string raising the error */
341 int *errCounts; /* counters at the error state */
342 int nbPush;
343 };
344
345 #define REGEXP_ALL_COUNTER 0x123456
346 #define REGEXP_ALL_LAX_COUNTER 0x123457
347
348 static void xmlFAParseRegExp(xmlRegParserCtxtPtr ctxt, int top);
349 static void xmlRegFreeState(xmlRegStatePtr state);
350 static void xmlRegFreeAtom(xmlRegAtomPtr atom);
351 static int xmlRegStrEqualWildcard(const xmlChar *expStr, const xmlChar *valStr);
352 static int xmlRegCheckCharacter(xmlRegAtomPtr atom, int codepoint);
353 static int xmlRegCheckCharacterRange(xmlRegAtomType type, int codepoint,
354 int neg, int start, int end, const xmlChar *blockName);
355
356 /************************************************************************
357 * *
358 * Regexp memory error handler *
359 * *
360 ************************************************************************/
361 /**
362 * xmlRegexpErrMemory:
363 * @extra: extra information
364 *
365 * Handle an out of memory condition
366 */
367 static void
xmlRegexpErrMemory(xmlRegParserCtxtPtr ctxt,const char * extra)368 xmlRegexpErrMemory(xmlRegParserCtxtPtr ctxt, const char *extra)
369 {
370 const char *regexp = NULL;
371 if (ctxt != NULL) {
372 regexp = (const char *) ctxt->string;
373 ctxt->error = XML_ERR_NO_MEMORY;
374 }
375 __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_REGEXP,
376 XML_ERR_NO_MEMORY, XML_ERR_FATAL, NULL, 0, extra,
377 regexp, NULL, 0, 0,
378 "Memory allocation failed : %s\n", extra);
379 }
380
381 /**
382 * xmlRegexpErrCompile:
383 * @extra: extra information
384 *
385 * Handle a compilation failure
386 */
387 static void
xmlRegexpErrCompile(xmlRegParserCtxtPtr ctxt,const char * extra)388 xmlRegexpErrCompile(xmlRegParserCtxtPtr ctxt, const char *extra)
389 {
390 const char *regexp = NULL;
391 int idx = 0;
392
393 if (ctxt != NULL) {
394 regexp = (const char *) ctxt->string;
395 idx = ctxt->cur - ctxt->string;
396 ctxt->error = XML_REGEXP_COMPILE_ERROR;
397 }
398 __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_REGEXP,
399 XML_REGEXP_COMPILE_ERROR, XML_ERR_FATAL, NULL, 0, extra,
400 regexp, NULL, idx, 0,
401 "failed to compile: %s\n", extra);
402 }
403
404 /************************************************************************
405 * *
406 * Allocation/Deallocation *
407 * *
408 ************************************************************************/
409
410 static int xmlFAComputesDeterminism(xmlRegParserCtxtPtr ctxt);
411 /**
412 * xmlRegEpxFromParse:
413 * @ctxt: the parser context used to build it
414 *
415 * Allocate a new regexp and fill it with the result from the parser
416 *
417 * Returns the new regexp or NULL in case of error
418 */
419 static xmlRegexpPtr
xmlRegEpxFromParse(xmlRegParserCtxtPtr ctxt)420 xmlRegEpxFromParse(xmlRegParserCtxtPtr ctxt) {
421 xmlRegexpPtr ret;
422
423 ret = (xmlRegexpPtr) xmlMalloc(sizeof(xmlRegexp));
424 if (ret == NULL) {
425 xmlRegexpErrMemory(ctxt, "compiling regexp");
426 return(NULL);
427 }
428 memset(ret, 0, sizeof(xmlRegexp));
429 ret->string = ctxt->string;
430 ret->nbStates = ctxt->nbStates;
431 ret->states = ctxt->states;
432 ret->nbAtoms = ctxt->nbAtoms;
433 ret->atoms = ctxt->atoms;
434 ret->nbCounters = ctxt->nbCounters;
435 ret->counters = ctxt->counters;
436 ret->determinist = ctxt->determinist;
437 if (ret->determinist == -1) {
438 xmlRegexpIsDeterminist(ret);
439 }
440
441 if ((ret->determinist != 0) &&
442 (ret->nbCounters == 0) &&
443 (ctxt->negs == 0) &&
444 (ret->atoms != NULL) &&
445 (ret->atoms[0] != NULL) &&
446 (ret->atoms[0]->type == XML_REGEXP_STRING)) {
447 int i, j, nbstates = 0, nbatoms = 0;
448 int *stateRemap;
449 int *stringRemap;
450 int *transitions;
451 void **transdata;
452 xmlChar **stringMap;
453 xmlChar *value;
454
455 /*
456 * Switch to a compact representation
457 * 1/ counting the effective number of states left
458 * 2/ counting the unique number of atoms, and check that
459 * they are all of the string type
460 * 3/ build a table state x atom for the transitions
461 */
462
463 stateRemap = xmlMalloc(ret->nbStates * sizeof(int));
464 if (stateRemap == NULL) {
465 xmlRegexpErrMemory(ctxt, "compiling regexp");
466 xmlFree(ret);
467 return(NULL);
468 }
469 for (i = 0;i < ret->nbStates;i++) {
470 if (ret->states[i] != NULL) {
471 stateRemap[i] = nbstates;
472 nbstates++;
473 } else {
474 stateRemap[i] = -1;
475 }
476 }
477 #ifdef DEBUG_COMPACTION
478 printf("Final: %d states\n", nbstates);
479 #endif
480 stringMap = xmlMalloc(ret->nbAtoms * sizeof(char *));
481 if (stringMap == NULL) {
482 xmlRegexpErrMemory(ctxt, "compiling regexp");
483 xmlFree(stateRemap);
484 xmlFree(ret);
485 return(NULL);
486 }
487 stringRemap = xmlMalloc(ret->nbAtoms * sizeof(int));
488 if (stringRemap == NULL) {
489 xmlRegexpErrMemory(ctxt, "compiling regexp");
490 xmlFree(stringMap);
491 xmlFree(stateRemap);
492 xmlFree(ret);
493 return(NULL);
494 }
495 for (i = 0;i < ret->nbAtoms;i++) {
496 if ((ret->atoms[i]->type == XML_REGEXP_STRING) &&
497 (ret->atoms[i]->quant == XML_REGEXP_QUANT_ONCE)) {
498 value = ret->atoms[i]->valuep;
499 for (j = 0;j < nbatoms;j++) {
500 if (xmlStrEqual(stringMap[j], value)) {
501 stringRemap[i] = j;
502 break;
503 }
504 }
505 if (j >= nbatoms) {
506 stringRemap[i] = nbatoms;
507 stringMap[nbatoms] = xmlStrdup(value);
508 if (stringMap[nbatoms] == NULL) {
509 for (i = 0;i < nbatoms;i++)
510 xmlFree(stringMap[i]);
511 xmlFree(stringRemap);
512 xmlFree(stringMap);
513 xmlFree(stateRemap);
514 xmlFree(ret);
515 return(NULL);
516 }
517 nbatoms++;
518 }
519 } else {
520 xmlFree(stateRemap);
521 xmlFree(stringRemap);
522 for (i = 0;i < nbatoms;i++)
523 xmlFree(stringMap[i]);
524 xmlFree(stringMap);
525 xmlFree(ret);
526 return(NULL);
527 }
528 }
529 #ifdef DEBUG_COMPACTION
530 printf("Final: %d atoms\n", nbatoms);
531 #endif
532 transitions = (int *) xmlMalloc((nbstates + 1) *
533 (nbatoms + 1) * sizeof(int));
534 if (transitions == NULL) {
535 xmlFree(stateRemap);
536 xmlFree(stringRemap);
537 xmlFree(stringMap);
538 xmlFree(ret);
539 return(NULL);
540 }
541 memset(transitions, 0, (nbstates + 1) * (nbatoms + 1) * sizeof(int));
542
543 /*
544 * Allocate the transition table. The first entry for each
545 * state corresponds to the state type.
546 */
547 transdata = NULL;
548
549 for (i = 0;i < ret->nbStates;i++) {
550 int stateno, atomno, targetno, prev;
551 xmlRegStatePtr state;
552 xmlRegTransPtr trans;
553
554 stateno = stateRemap[i];
555 if (stateno == -1)
556 continue;
557 state = ret->states[i];
558
559 transitions[stateno * (nbatoms + 1)] = state->type;
560
561 for (j = 0;j < state->nbTrans;j++) {
562 trans = &(state->trans[j]);
563 if ((trans->to == -1) || (trans->atom == NULL))
564 continue;
565 atomno = stringRemap[trans->atom->no];
566 if ((trans->atom->data != NULL) && (transdata == NULL)) {
567 transdata = (void **) xmlMalloc(nbstates * nbatoms *
568 sizeof(void *));
569 if (transdata != NULL)
570 memset(transdata, 0,
571 nbstates * nbatoms * sizeof(void *));
572 else {
573 xmlRegexpErrMemory(ctxt, "compiling regexp");
574 break;
575 }
576 }
577 targetno = stateRemap[trans->to];
578 /*
579 * if the same atom can generate transitions to 2 different
580 * states then it means the automata is not determinist and
581 * the compact form can't be used !
582 */
583 prev = transitions[stateno * (nbatoms + 1) + atomno + 1];
584 if (prev != 0) {
585 if (prev != targetno + 1) {
586 ret->determinist = 0;
587 #ifdef DEBUG_COMPACTION
588 printf("Indet: state %d trans %d, atom %d to %d : %d to %d\n",
589 i, j, trans->atom->no, trans->to, atomno, targetno);
590 printf(" previous to is %d\n", prev);
591 #endif
592 if (transdata != NULL)
593 xmlFree(transdata);
594 xmlFree(transitions);
595 xmlFree(stateRemap);
596 xmlFree(stringRemap);
597 for (i = 0;i < nbatoms;i++)
598 xmlFree(stringMap[i]);
599 xmlFree(stringMap);
600 goto not_determ;
601 }
602 } else {
603 #if 0
604 printf("State %d trans %d: atom %d to %d : %d to %d\n",
605 i, j, trans->atom->no, trans->to, atomno, targetno);
606 #endif
607 transitions[stateno * (nbatoms + 1) + atomno + 1] =
608 targetno + 1; /* to avoid 0 */
609 if (transdata != NULL)
610 transdata[stateno * nbatoms + atomno] =
611 trans->atom->data;
612 }
613 }
614 }
615 ret->determinist = 1;
616 #ifdef DEBUG_COMPACTION
617 /*
618 * Debug
619 */
620 for (i = 0;i < nbstates;i++) {
621 for (j = 0;j < nbatoms + 1;j++) {
622 printf("%02d ", transitions[i * (nbatoms + 1) + j]);
623 }
624 printf("\n");
625 }
626 printf("\n");
627 #endif
628 /*
629 * Cleanup of the old data
630 */
631 if (ret->states != NULL) {
632 for (i = 0;i < ret->nbStates;i++)
633 xmlRegFreeState(ret->states[i]);
634 xmlFree(ret->states);
635 }
636 ret->states = NULL;
637 ret->nbStates = 0;
638 if (ret->atoms != NULL) {
639 for (i = 0;i < ret->nbAtoms;i++)
640 xmlRegFreeAtom(ret->atoms[i]);
641 xmlFree(ret->atoms);
642 }
643 ret->atoms = NULL;
644 ret->nbAtoms = 0;
645
646 ret->compact = transitions;
647 ret->transdata = transdata;
648 ret->stringMap = stringMap;
649 ret->nbstrings = nbatoms;
650 ret->nbstates = nbstates;
651 xmlFree(stateRemap);
652 xmlFree(stringRemap);
653 }
654 not_determ:
655 ctxt->string = NULL;
656 ctxt->nbStates = 0;
657 ctxt->states = NULL;
658 ctxt->nbAtoms = 0;
659 ctxt->atoms = NULL;
660 ctxt->nbCounters = 0;
661 ctxt->counters = NULL;
662 return(ret);
663 }
664
665 /**
666 * xmlRegNewParserCtxt:
667 * @string: the string to parse
668 *
669 * Allocate a new regexp parser context
670 *
671 * Returns the new context or NULL in case of error
672 */
673 static xmlRegParserCtxtPtr
xmlRegNewParserCtxt(const xmlChar * string)674 xmlRegNewParserCtxt(const xmlChar *string) {
675 xmlRegParserCtxtPtr ret;
676
677 ret = (xmlRegParserCtxtPtr) xmlMalloc(sizeof(xmlRegParserCtxt));
678 if (ret == NULL)
679 return(NULL);
680 memset(ret, 0, sizeof(xmlRegParserCtxt));
681 if (string != NULL)
682 ret->string = xmlStrdup(string);
683 ret->cur = ret->string;
684 ret->neg = 0;
685 ret->negs = 0;
686 ret->error = 0;
687 ret->determinist = -1;
688 return(ret);
689 }
690
691 /**
692 * xmlRegNewRange:
693 * @ctxt: the regexp parser context
694 * @neg: is that negative
695 * @type: the type of range
696 * @start: the start codepoint
697 * @end: the end codepoint
698 *
699 * Allocate a new regexp range
700 *
701 * Returns the new range or NULL in case of error
702 */
703 static xmlRegRangePtr
xmlRegNewRange(xmlRegParserCtxtPtr ctxt,int neg,xmlRegAtomType type,int start,int end)704 xmlRegNewRange(xmlRegParserCtxtPtr ctxt,
705 int neg, xmlRegAtomType type, int start, int end) {
706 xmlRegRangePtr ret;
707
708 ret = (xmlRegRangePtr) xmlMalloc(sizeof(xmlRegRange));
709 if (ret == NULL) {
710 xmlRegexpErrMemory(ctxt, "allocating range");
711 return(NULL);
712 }
713 ret->neg = neg;
714 ret->type = type;
715 ret->start = start;
716 ret->end = end;
717 return(ret);
718 }
719
720 /**
721 * xmlRegFreeRange:
722 * @range: the regexp range
723 *
724 * Free a regexp range
725 */
726 static void
xmlRegFreeRange(xmlRegRangePtr range)727 xmlRegFreeRange(xmlRegRangePtr range) {
728 if (range == NULL)
729 return;
730
731 if (range->blockName != NULL)
732 xmlFree(range->blockName);
733 xmlFree(range);
734 }
735
736 /**
737 * xmlRegCopyRange:
738 * @range: the regexp range
739 *
740 * Copy a regexp range
741 *
742 * Returns the new copy or NULL in case of error.
743 */
744 static xmlRegRangePtr
xmlRegCopyRange(xmlRegParserCtxtPtr ctxt,xmlRegRangePtr range)745 xmlRegCopyRange(xmlRegParserCtxtPtr ctxt, xmlRegRangePtr range) {
746 xmlRegRangePtr ret;
747
748 if (range == NULL)
749 return(NULL);
750
751 ret = xmlRegNewRange(ctxt, range->neg, range->type, range->start,
752 range->end);
753 if (ret == NULL)
754 return(NULL);
755 if (range->blockName != NULL) {
756 ret->blockName = xmlStrdup(range->blockName);
757 if (ret->blockName == NULL) {
758 xmlRegexpErrMemory(ctxt, "allocating range");
759 xmlRegFreeRange(ret);
760 return(NULL);
761 }
762 }
763 return(ret);
764 }
765
766 /**
767 * xmlRegNewAtom:
768 * @ctxt: the regexp parser context
769 * @type: the type of atom
770 *
771 * Allocate a new atom
772 *
773 * Returns the new atom or NULL in case of error
774 */
775 static xmlRegAtomPtr
xmlRegNewAtom(xmlRegParserCtxtPtr ctxt,xmlRegAtomType type)776 xmlRegNewAtom(xmlRegParserCtxtPtr ctxt, xmlRegAtomType type) {
777 xmlRegAtomPtr ret;
778
779 ret = (xmlRegAtomPtr) xmlMalloc(sizeof(xmlRegAtom));
780 if (ret == NULL) {
781 xmlRegexpErrMemory(ctxt, "allocating atom");
782 return(NULL);
783 }
784 memset(ret, 0, sizeof(xmlRegAtom));
785 ret->type = type;
786 ret->quant = XML_REGEXP_QUANT_ONCE;
787 ret->min = 0;
788 ret->max = 0;
789 return(ret);
790 }
791
792 /**
793 * xmlRegFreeAtom:
794 * @atom: the regexp atom
795 *
796 * Free a regexp atom
797 */
798 static void
xmlRegFreeAtom(xmlRegAtomPtr atom)799 xmlRegFreeAtom(xmlRegAtomPtr atom) {
800 int i;
801
802 if (atom == NULL)
803 return;
804
805 for (i = 0;i < atom->nbRanges;i++)
806 xmlRegFreeRange(atom->ranges[i]);
807 if (atom->ranges != NULL)
808 xmlFree(atom->ranges);
809 if ((atom->type == XML_REGEXP_STRING) && (atom->valuep != NULL))
810 xmlFree(atom->valuep);
811 if ((atom->type == XML_REGEXP_STRING) && (atom->valuep2 != NULL))
812 xmlFree(atom->valuep2);
813 if ((atom->type == XML_REGEXP_BLOCK_NAME) && (atom->valuep != NULL))
814 xmlFree(atom->valuep);
815 xmlFree(atom);
816 }
817
818 /**
819 * xmlRegCopyAtom:
820 * @ctxt: the regexp parser context
821 * @atom: the oiginal atom
822 *
823 * Allocate a new regexp range
824 *
825 * Returns the new atom or NULL in case of error
826 */
827 static xmlRegAtomPtr
xmlRegCopyAtom(xmlRegParserCtxtPtr ctxt,xmlRegAtomPtr atom)828 xmlRegCopyAtom(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom) {
829 xmlRegAtomPtr ret;
830
831 ret = (xmlRegAtomPtr) xmlMalloc(sizeof(xmlRegAtom));
832 if (ret == NULL) {
833 xmlRegexpErrMemory(ctxt, "copying atom");
834 return(NULL);
835 }
836 memset(ret, 0, sizeof(xmlRegAtom));
837 ret->type = atom->type;
838 ret->quant = atom->quant;
839 ret->min = atom->min;
840 ret->max = atom->max;
841 if (atom->nbRanges > 0) {
842 int i;
843
844 ret->ranges = (xmlRegRangePtr *) xmlMalloc(sizeof(xmlRegRangePtr) *
845 atom->nbRanges);
846 if (ret->ranges == NULL) {
847 xmlRegexpErrMemory(ctxt, "copying atom");
848 goto error;
849 }
850 for (i = 0;i < atom->nbRanges;i++) {
851 ret->ranges[i] = xmlRegCopyRange(ctxt, atom->ranges[i]);
852 if (ret->ranges[i] == NULL)
853 goto error;
854 ret->nbRanges = i + 1;
855 }
856 }
857 return(ret);
858
859 error:
860 xmlRegFreeAtom(ret);
861 return(NULL);
862 }
863
864 static xmlRegStatePtr
xmlRegNewState(xmlRegParserCtxtPtr ctxt)865 xmlRegNewState(xmlRegParserCtxtPtr ctxt) {
866 xmlRegStatePtr ret;
867
868 ret = (xmlRegStatePtr) xmlMalloc(sizeof(xmlRegState));
869 if (ret == NULL) {
870 xmlRegexpErrMemory(ctxt, "allocating state");
871 return(NULL);
872 }
873 memset(ret, 0, sizeof(xmlRegState));
874 ret->type = XML_REGEXP_TRANS_STATE;
875 ret->mark = XML_REGEXP_MARK_NORMAL;
876 return(ret);
877 }
878
879 /**
880 * xmlRegFreeState:
881 * @state: the regexp state
882 *
883 * Free a regexp state
884 */
885 static void
xmlRegFreeState(xmlRegStatePtr state)886 xmlRegFreeState(xmlRegStatePtr state) {
887 if (state == NULL)
888 return;
889
890 if (state->trans != NULL)
891 xmlFree(state->trans);
892 if (state->transTo != NULL)
893 xmlFree(state->transTo);
894 xmlFree(state);
895 }
896
897 /**
898 * xmlRegFreeParserCtxt:
899 * @ctxt: the regexp parser context
900 *
901 * Free a regexp parser context
902 */
903 static void
xmlRegFreeParserCtxt(xmlRegParserCtxtPtr ctxt)904 xmlRegFreeParserCtxt(xmlRegParserCtxtPtr ctxt) {
905 int i;
906 if (ctxt == NULL)
907 return;
908
909 if (ctxt->string != NULL)
910 xmlFree(ctxt->string);
911 if (ctxt->states != NULL) {
912 for (i = 0;i < ctxt->nbStates;i++)
913 xmlRegFreeState(ctxt->states[i]);
914 xmlFree(ctxt->states);
915 }
916 if (ctxt->atoms != NULL) {
917 for (i = 0;i < ctxt->nbAtoms;i++)
918 xmlRegFreeAtom(ctxt->atoms[i]);
919 xmlFree(ctxt->atoms);
920 }
921 if (ctxt->counters != NULL)
922 xmlFree(ctxt->counters);
923 xmlFree(ctxt);
924 }
925
926 /************************************************************************
927 * *
928 * Display of Data structures *
929 * *
930 ************************************************************************/
931
932 static void
xmlRegPrintAtomType(FILE * output,xmlRegAtomType type)933 xmlRegPrintAtomType(FILE *output, xmlRegAtomType type) {
934 switch (type) {
935 case XML_REGEXP_EPSILON:
936 fprintf(output, "epsilon "); break;
937 case XML_REGEXP_CHARVAL:
938 fprintf(output, "charval "); break;
939 case XML_REGEXP_RANGES:
940 fprintf(output, "ranges "); break;
941 case XML_REGEXP_SUBREG:
942 fprintf(output, "subexpr "); break;
943 case XML_REGEXP_STRING:
944 fprintf(output, "string "); break;
945 case XML_REGEXP_ANYCHAR:
946 fprintf(output, "anychar "); break;
947 case XML_REGEXP_ANYSPACE:
948 fprintf(output, "anyspace "); break;
949 case XML_REGEXP_NOTSPACE:
950 fprintf(output, "notspace "); break;
951 case XML_REGEXP_INITNAME:
952 fprintf(output, "initname "); break;
953 case XML_REGEXP_NOTINITNAME:
954 fprintf(output, "notinitname "); break;
955 case XML_REGEXP_NAMECHAR:
956 fprintf(output, "namechar "); break;
957 case XML_REGEXP_NOTNAMECHAR:
958 fprintf(output, "notnamechar "); break;
959 case XML_REGEXP_DECIMAL:
960 fprintf(output, "decimal "); break;
961 case XML_REGEXP_NOTDECIMAL:
962 fprintf(output, "notdecimal "); break;
963 case XML_REGEXP_REALCHAR:
964 fprintf(output, "realchar "); break;
965 case XML_REGEXP_NOTREALCHAR:
966 fprintf(output, "notrealchar "); break;
967 case XML_REGEXP_LETTER:
968 fprintf(output, "LETTER "); break;
969 case XML_REGEXP_LETTER_UPPERCASE:
970 fprintf(output, "LETTER_UPPERCASE "); break;
971 case XML_REGEXP_LETTER_LOWERCASE:
972 fprintf(output, "LETTER_LOWERCASE "); break;
973 case XML_REGEXP_LETTER_TITLECASE:
974 fprintf(output, "LETTER_TITLECASE "); break;
975 case XML_REGEXP_LETTER_MODIFIER:
976 fprintf(output, "LETTER_MODIFIER "); break;
977 case XML_REGEXP_LETTER_OTHERS:
978 fprintf(output, "LETTER_OTHERS "); break;
979 case XML_REGEXP_MARK:
980 fprintf(output, "MARK "); break;
981 case XML_REGEXP_MARK_NONSPACING:
982 fprintf(output, "MARK_NONSPACING "); break;
983 case XML_REGEXP_MARK_SPACECOMBINING:
984 fprintf(output, "MARK_SPACECOMBINING "); break;
985 case XML_REGEXP_MARK_ENCLOSING:
986 fprintf(output, "MARK_ENCLOSING "); break;
987 case XML_REGEXP_NUMBER:
988 fprintf(output, "NUMBER "); break;
989 case XML_REGEXP_NUMBER_DECIMAL:
990 fprintf(output, "NUMBER_DECIMAL "); break;
991 case XML_REGEXP_NUMBER_LETTER:
992 fprintf(output, "NUMBER_LETTER "); break;
993 case XML_REGEXP_NUMBER_OTHERS:
994 fprintf(output, "NUMBER_OTHERS "); break;
995 case XML_REGEXP_PUNCT:
996 fprintf(output, "PUNCT "); break;
997 case XML_REGEXP_PUNCT_CONNECTOR:
998 fprintf(output, "PUNCT_CONNECTOR "); break;
999 case XML_REGEXP_PUNCT_DASH:
1000 fprintf(output, "PUNCT_DASH "); break;
1001 case XML_REGEXP_PUNCT_OPEN:
1002 fprintf(output, "PUNCT_OPEN "); break;
1003 case XML_REGEXP_PUNCT_CLOSE:
1004 fprintf(output, "PUNCT_CLOSE "); break;
1005 case XML_REGEXP_PUNCT_INITQUOTE:
1006 fprintf(output, "PUNCT_INITQUOTE "); break;
1007 case XML_REGEXP_PUNCT_FINQUOTE:
1008 fprintf(output, "PUNCT_FINQUOTE "); break;
1009 case XML_REGEXP_PUNCT_OTHERS:
1010 fprintf(output, "PUNCT_OTHERS "); break;
1011 case XML_REGEXP_SEPAR:
1012 fprintf(output, "SEPAR "); break;
1013 case XML_REGEXP_SEPAR_SPACE:
1014 fprintf(output, "SEPAR_SPACE "); break;
1015 case XML_REGEXP_SEPAR_LINE:
1016 fprintf(output, "SEPAR_LINE "); break;
1017 case XML_REGEXP_SEPAR_PARA:
1018 fprintf(output, "SEPAR_PARA "); break;
1019 case XML_REGEXP_SYMBOL:
1020 fprintf(output, "SYMBOL "); break;
1021 case XML_REGEXP_SYMBOL_MATH:
1022 fprintf(output, "SYMBOL_MATH "); break;
1023 case XML_REGEXP_SYMBOL_CURRENCY:
1024 fprintf(output, "SYMBOL_CURRENCY "); break;
1025 case XML_REGEXP_SYMBOL_MODIFIER:
1026 fprintf(output, "SYMBOL_MODIFIER "); break;
1027 case XML_REGEXP_SYMBOL_OTHERS:
1028 fprintf(output, "SYMBOL_OTHERS "); break;
1029 case XML_REGEXP_OTHER:
1030 fprintf(output, "OTHER "); break;
1031 case XML_REGEXP_OTHER_CONTROL:
1032 fprintf(output, "OTHER_CONTROL "); break;
1033 case XML_REGEXP_OTHER_FORMAT:
1034 fprintf(output, "OTHER_FORMAT "); break;
1035 case XML_REGEXP_OTHER_PRIVATE:
1036 fprintf(output, "OTHER_PRIVATE "); break;
1037 case XML_REGEXP_OTHER_NA:
1038 fprintf(output, "OTHER_NA "); break;
1039 case XML_REGEXP_BLOCK_NAME:
1040 fprintf(output, "BLOCK "); break;
1041 }
1042 }
1043
1044 static void
xmlRegPrintQuantType(FILE * output,xmlRegQuantType type)1045 xmlRegPrintQuantType(FILE *output, xmlRegQuantType type) {
1046 switch (type) {
1047 case XML_REGEXP_QUANT_EPSILON:
1048 fprintf(output, "epsilon "); break;
1049 case XML_REGEXP_QUANT_ONCE:
1050 fprintf(output, "once "); break;
1051 case XML_REGEXP_QUANT_OPT:
1052 fprintf(output, "? "); break;
1053 case XML_REGEXP_QUANT_MULT:
1054 fprintf(output, "* "); break;
1055 case XML_REGEXP_QUANT_PLUS:
1056 fprintf(output, "+ "); break;
1057 case XML_REGEXP_QUANT_RANGE:
1058 fprintf(output, "range "); break;
1059 case XML_REGEXP_QUANT_ONCEONLY:
1060 fprintf(output, "onceonly "); break;
1061 case XML_REGEXP_QUANT_ALL:
1062 fprintf(output, "all "); break;
1063 }
1064 }
1065 static void
xmlRegPrintRange(FILE * output,xmlRegRangePtr range)1066 xmlRegPrintRange(FILE *output, xmlRegRangePtr range) {
1067 fprintf(output, " range: ");
1068 if (range->neg)
1069 fprintf(output, "negative ");
1070 xmlRegPrintAtomType(output, range->type);
1071 fprintf(output, "%c - %c\n", range->start, range->end);
1072 }
1073
1074 static void
xmlRegPrintAtom(FILE * output,xmlRegAtomPtr atom)1075 xmlRegPrintAtom(FILE *output, xmlRegAtomPtr atom) {
1076 fprintf(output, " atom: ");
1077 if (atom == NULL) {
1078 fprintf(output, "NULL\n");
1079 return;
1080 }
1081 if (atom->neg)
1082 fprintf(output, "not ");
1083 xmlRegPrintAtomType(output, atom->type);
1084 xmlRegPrintQuantType(output, atom->quant);
1085 if (atom->quant == XML_REGEXP_QUANT_RANGE)
1086 fprintf(output, "%d-%d ", atom->min, atom->max);
1087 if (atom->type == XML_REGEXP_STRING)
1088 fprintf(output, "'%s' ", (char *) atom->valuep);
1089 if (atom->type == XML_REGEXP_CHARVAL)
1090 fprintf(output, "char %c\n", atom->codepoint);
1091 else if (atom->type == XML_REGEXP_RANGES) {
1092 int i;
1093 fprintf(output, "%d entries\n", atom->nbRanges);
1094 for (i = 0; i < atom->nbRanges;i++)
1095 xmlRegPrintRange(output, atom->ranges[i]);
1096 } else if (atom->type == XML_REGEXP_SUBREG) {
1097 fprintf(output, "start %d end %d\n", atom->start->no, atom->stop->no);
1098 } else {
1099 fprintf(output, "\n");
1100 }
1101 }
1102
1103 static void
xmlRegPrintTrans(FILE * output,xmlRegTransPtr trans)1104 xmlRegPrintTrans(FILE *output, xmlRegTransPtr trans) {
1105 fprintf(output, " trans: ");
1106 if (trans == NULL) {
1107 fprintf(output, "NULL\n");
1108 return;
1109 }
1110 if (trans->to < 0) {
1111 fprintf(output, "removed\n");
1112 return;
1113 }
1114 if (trans->nd != 0) {
1115 if (trans->nd == 2)
1116 fprintf(output, "last not determinist, ");
1117 else
1118 fprintf(output, "not determinist, ");
1119 }
1120 if (trans->counter >= 0) {
1121 fprintf(output, "counted %d, ", trans->counter);
1122 }
1123 if (trans->count == REGEXP_ALL_COUNTER) {
1124 fprintf(output, "all transition, ");
1125 } else if (trans->count >= 0) {
1126 fprintf(output, "count based %d, ", trans->count);
1127 }
1128 if (trans->atom == NULL) {
1129 fprintf(output, "epsilon to %d\n", trans->to);
1130 return;
1131 }
1132 if (trans->atom->type == XML_REGEXP_CHARVAL)
1133 fprintf(output, "char %c ", trans->atom->codepoint);
1134 fprintf(output, "atom %d, to %d\n", trans->atom->no, trans->to);
1135 }
1136
1137 static void
xmlRegPrintState(FILE * output,xmlRegStatePtr state)1138 xmlRegPrintState(FILE *output, xmlRegStatePtr state) {
1139 int i;
1140
1141 fprintf(output, " state: ");
1142 if (state == NULL) {
1143 fprintf(output, "NULL\n");
1144 return;
1145 }
1146 if (state->type == XML_REGEXP_START_STATE)
1147 fprintf(output, "START ");
1148 if (state->type == XML_REGEXP_FINAL_STATE)
1149 fprintf(output, "FINAL ");
1150
1151 fprintf(output, "%d, %d transitions:\n", state->no, state->nbTrans);
1152 for (i = 0;i < state->nbTrans; i++) {
1153 xmlRegPrintTrans(output, &(state->trans[i]));
1154 }
1155 }
1156
1157 #ifdef DEBUG_REGEXP_GRAPH
1158 static void
xmlRegPrintCtxt(FILE * output,xmlRegParserCtxtPtr ctxt)1159 xmlRegPrintCtxt(FILE *output, xmlRegParserCtxtPtr ctxt) {
1160 int i;
1161
1162 fprintf(output, " ctxt: ");
1163 if (ctxt == NULL) {
1164 fprintf(output, "NULL\n");
1165 return;
1166 }
1167 fprintf(output, "'%s' ", ctxt->string);
1168 if (ctxt->error)
1169 fprintf(output, "error ");
1170 if (ctxt->neg)
1171 fprintf(output, "neg ");
1172 fprintf(output, "\n");
1173 fprintf(output, "%d atoms:\n", ctxt->nbAtoms);
1174 for (i = 0;i < ctxt->nbAtoms; i++) {
1175 fprintf(output, " %02d ", i);
1176 xmlRegPrintAtom(output, ctxt->atoms[i]);
1177 }
1178 if (ctxt->atom != NULL) {
1179 fprintf(output, "current atom:\n");
1180 xmlRegPrintAtom(output, ctxt->atom);
1181 }
1182 fprintf(output, "%d states:", ctxt->nbStates);
1183 if (ctxt->start != NULL)
1184 fprintf(output, " start: %d", ctxt->start->no);
1185 if (ctxt->end != NULL)
1186 fprintf(output, " end: %d", ctxt->end->no);
1187 fprintf(output, "\n");
1188 for (i = 0;i < ctxt->nbStates; i++) {
1189 xmlRegPrintState(output, ctxt->states[i]);
1190 }
1191 fprintf(output, "%d counters:\n", ctxt->nbCounters);
1192 for (i = 0;i < ctxt->nbCounters; i++) {
1193 fprintf(output, " %d: min %d max %d\n", i, ctxt->counters[i].min,
1194 ctxt->counters[i].max);
1195 }
1196 }
1197 #endif
1198
1199 /************************************************************************
1200 * *
1201 * Finite Automata structures manipulations *
1202 * *
1203 ************************************************************************/
1204
1205 static void
xmlRegAtomAddRange(xmlRegParserCtxtPtr ctxt,xmlRegAtomPtr atom,int neg,xmlRegAtomType type,int start,int end,xmlChar * blockName)1206 xmlRegAtomAddRange(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom,
1207 int neg, xmlRegAtomType type, int start, int end,
1208 xmlChar *blockName) {
1209 xmlRegRangePtr range;
1210
1211 if (atom == NULL) {
1212 ERROR("add range: atom is NULL");
1213 return;
1214 }
1215 if (atom->type != XML_REGEXP_RANGES) {
1216 ERROR("add range: atom is not ranges");
1217 return;
1218 }
1219 if (atom->maxRanges == 0) {
1220 atom->maxRanges = 4;
1221 atom->ranges = (xmlRegRangePtr *) xmlMalloc(atom->maxRanges *
1222 sizeof(xmlRegRangePtr));
1223 if (atom->ranges == NULL) {
1224 xmlRegexpErrMemory(ctxt, "adding ranges");
1225 atom->maxRanges = 0;
1226 return;
1227 }
1228 } else if (atom->nbRanges >= atom->maxRanges) {
1229 xmlRegRangePtr *tmp;
1230 atom->maxRanges *= 2;
1231 tmp = (xmlRegRangePtr *) xmlRealloc(atom->ranges, atom->maxRanges *
1232 sizeof(xmlRegRangePtr));
1233 if (tmp == NULL) {
1234 xmlRegexpErrMemory(ctxt, "adding ranges");
1235 atom->maxRanges /= 2;
1236 return;
1237 }
1238 atom->ranges = tmp;
1239 }
1240 range = xmlRegNewRange(ctxt, neg, type, start, end);
1241 if (range == NULL)
1242 return;
1243 range->blockName = blockName;
1244 atom->ranges[atom->nbRanges++] = range;
1245
1246 }
1247
1248 static int
xmlRegGetCounter(xmlRegParserCtxtPtr ctxt)1249 xmlRegGetCounter(xmlRegParserCtxtPtr ctxt) {
1250 if (ctxt->maxCounters == 0) {
1251 ctxt->maxCounters = 4;
1252 ctxt->counters = (xmlRegCounter *) xmlMalloc(ctxt->maxCounters *
1253 sizeof(xmlRegCounter));
1254 if (ctxt->counters == NULL) {
1255 xmlRegexpErrMemory(ctxt, "allocating counter");
1256 ctxt->maxCounters = 0;
1257 return(-1);
1258 }
1259 } else if (ctxt->nbCounters >= ctxt->maxCounters) {
1260 xmlRegCounter *tmp;
1261 ctxt->maxCounters *= 2;
1262 tmp = (xmlRegCounter *) xmlRealloc(ctxt->counters, ctxt->maxCounters *
1263 sizeof(xmlRegCounter));
1264 if (tmp == NULL) {
1265 xmlRegexpErrMemory(ctxt, "allocating counter");
1266 ctxt->maxCounters /= 2;
1267 return(-1);
1268 }
1269 ctxt->counters = tmp;
1270 }
1271 ctxt->counters[ctxt->nbCounters].min = -1;
1272 ctxt->counters[ctxt->nbCounters].max = -1;
1273 return(ctxt->nbCounters++);
1274 }
1275
1276 static int
xmlRegAtomPush(xmlRegParserCtxtPtr ctxt,xmlRegAtomPtr atom)1277 xmlRegAtomPush(xmlRegParserCtxtPtr ctxt, xmlRegAtomPtr atom) {
1278 if (atom == NULL) {
1279 ERROR("atom push: atom is NULL");
1280 return(-1);
1281 }
1282 if (ctxt->maxAtoms == 0) {
1283 ctxt->maxAtoms = 4;
1284 ctxt->atoms = (xmlRegAtomPtr *) xmlMalloc(ctxt->maxAtoms *
1285 sizeof(xmlRegAtomPtr));
1286 if (ctxt->atoms == NULL) {
1287 xmlRegexpErrMemory(ctxt, "pushing atom");
1288 ctxt->maxAtoms = 0;
1289 return(-1);
1290 }
1291 } else if (ctxt->nbAtoms >= ctxt->maxAtoms) {
1292 xmlRegAtomPtr *tmp;
1293 ctxt->maxAtoms *= 2;
1294 tmp = (xmlRegAtomPtr *) xmlRealloc(ctxt->atoms, ctxt->maxAtoms *
1295 sizeof(xmlRegAtomPtr));
1296 if (tmp == NULL) {
1297 xmlRegexpErrMemory(ctxt, "allocating counter");
1298 ctxt->maxAtoms /= 2;
1299 return(-1);
1300 }
1301 ctxt->atoms = tmp;
1302 }
1303 atom->no = ctxt->nbAtoms;
1304 ctxt->atoms[ctxt->nbAtoms++] = atom;
1305 return(0);
1306 }
1307
1308 static void
xmlRegStateAddTransTo(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr target,int from)1309 xmlRegStateAddTransTo(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr target,
1310 int from) {
1311 if (target->maxTransTo == 0) {
1312 target->maxTransTo = 8;
1313 target->transTo = (int *) xmlMalloc(target->maxTransTo *
1314 sizeof(int));
1315 if (target->transTo == NULL) {
1316 xmlRegexpErrMemory(ctxt, "adding transition");
1317 target->maxTransTo = 0;
1318 return;
1319 }
1320 } else if (target->nbTransTo >= target->maxTransTo) {
1321 int *tmp;
1322 target->maxTransTo *= 2;
1323 tmp = (int *) xmlRealloc(target->transTo, target->maxTransTo *
1324 sizeof(int));
1325 if (tmp == NULL) {
1326 xmlRegexpErrMemory(ctxt, "adding transition");
1327 target->maxTransTo /= 2;
1328 return;
1329 }
1330 target->transTo = tmp;
1331 }
1332 target->transTo[target->nbTransTo] = from;
1333 target->nbTransTo++;
1334 }
1335
1336 static void
xmlRegStateAddTrans(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr state,xmlRegAtomPtr atom,xmlRegStatePtr target,int counter,int count)1337 xmlRegStateAddTrans(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state,
1338 xmlRegAtomPtr atom, xmlRegStatePtr target,
1339 int counter, int count) {
1340
1341 int nrtrans;
1342
1343 if (state == NULL) {
1344 ERROR("add state: state is NULL");
1345 return;
1346 }
1347 if (target == NULL) {
1348 ERROR("add state: target is NULL");
1349 return;
1350 }
1351 /*
1352 * Other routines follow the philosophy 'When in doubt, add a transition'
1353 * so we check here whether such a transition is already present and, if
1354 * so, silently ignore this request.
1355 */
1356
1357 for (nrtrans = state->nbTrans - 1; nrtrans >= 0; nrtrans--) {
1358 xmlRegTransPtr trans = &(state->trans[nrtrans]);
1359 if ((trans->atom == atom) &&
1360 (trans->to == target->no) &&
1361 (trans->counter == counter) &&
1362 (trans->count == count)) {
1363 #ifdef DEBUG_REGEXP_GRAPH
1364 printf("Ignoring duplicate transition from %d to %d\n",
1365 state->no, target->no);
1366 #endif
1367 return;
1368 }
1369 }
1370
1371 if (state->maxTrans == 0) {
1372 state->maxTrans = 8;
1373 state->trans = (xmlRegTrans *) xmlMalloc(state->maxTrans *
1374 sizeof(xmlRegTrans));
1375 if (state->trans == NULL) {
1376 xmlRegexpErrMemory(ctxt, "adding transition");
1377 state->maxTrans = 0;
1378 return;
1379 }
1380 } else if (state->nbTrans >= state->maxTrans) {
1381 xmlRegTrans *tmp;
1382 state->maxTrans *= 2;
1383 tmp = (xmlRegTrans *) xmlRealloc(state->trans, state->maxTrans *
1384 sizeof(xmlRegTrans));
1385 if (tmp == NULL) {
1386 xmlRegexpErrMemory(ctxt, "adding transition");
1387 state->maxTrans /= 2;
1388 return;
1389 }
1390 state->trans = tmp;
1391 }
1392 #ifdef DEBUG_REGEXP_GRAPH
1393 printf("Add trans from %d to %d ", state->no, target->no);
1394 if (count == REGEXP_ALL_COUNTER)
1395 printf("all transition\n");
1396 else if (count >= 0)
1397 printf("count based %d\n", count);
1398 else if (counter >= 0)
1399 printf("counted %d\n", counter);
1400 else if (atom == NULL)
1401 printf("epsilon transition\n");
1402 else if (atom != NULL)
1403 xmlRegPrintAtom(stdout, atom);
1404 #endif
1405
1406 state->trans[state->nbTrans].atom = atom;
1407 state->trans[state->nbTrans].to = target->no;
1408 state->trans[state->nbTrans].counter = counter;
1409 state->trans[state->nbTrans].count = count;
1410 state->trans[state->nbTrans].nd = 0;
1411 state->nbTrans++;
1412 xmlRegStateAddTransTo(ctxt, target, state->no);
1413 }
1414
1415 static int
xmlRegStatePush(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr state)1416 xmlRegStatePush(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state) {
1417 if (state == NULL) return(-1);
1418 if (ctxt->maxStates == 0) {
1419 ctxt->maxStates = 4;
1420 ctxt->states = (xmlRegStatePtr *) xmlMalloc(ctxt->maxStates *
1421 sizeof(xmlRegStatePtr));
1422 if (ctxt->states == NULL) {
1423 xmlRegexpErrMemory(ctxt, "adding state");
1424 ctxt->maxStates = 0;
1425 return(-1);
1426 }
1427 } else if (ctxt->nbStates >= ctxt->maxStates) {
1428 xmlRegStatePtr *tmp;
1429 ctxt->maxStates *= 2;
1430 tmp = (xmlRegStatePtr *) xmlRealloc(ctxt->states, ctxt->maxStates *
1431 sizeof(xmlRegStatePtr));
1432 if (tmp == NULL) {
1433 xmlRegexpErrMemory(ctxt, "adding state");
1434 ctxt->maxStates /= 2;
1435 return(-1);
1436 }
1437 ctxt->states = tmp;
1438 }
1439 state->no = ctxt->nbStates;
1440 ctxt->states[ctxt->nbStates++] = state;
1441 return(0);
1442 }
1443
1444 /**
1445 * xmlFAGenerateAllTransition:
1446 * @ctxt: a regexp parser context
1447 * @from: the from state
1448 * @to: the target state or NULL for building a new one
1449 * @lax:
1450 *
1451 */
1452 static void
xmlFAGenerateAllTransition(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr from,xmlRegStatePtr to,int lax)1453 xmlFAGenerateAllTransition(xmlRegParserCtxtPtr ctxt,
1454 xmlRegStatePtr from, xmlRegStatePtr to,
1455 int lax) {
1456 if (to == NULL) {
1457 to = xmlRegNewState(ctxt);
1458 xmlRegStatePush(ctxt, to);
1459 ctxt->state = to;
1460 }
1461 if (lax)
1462 xmlRegStateAddTrans(ctxt, from, NULL, to, -1, REGEXP_ALL_LAX_COUNTER);
1463 else
1464 xmlRegStateAddTrans(ctxt, from, NULL, to, -1, REGEXP_ALL_COUNTER);
1465 }
1466
1467 /**
1468 * xmlFAGenerateEpsilonTransition:
1469 * @ctxt: a regexp parser context
1470 * @from: the from state
1471 * @to: the target state or NULL for building a new one
1472 *
1473 */
1474 static void
xmlFAGenerateEpsilonTransition(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr from,xmlRegStatePtr to)1475 xmlFAGenerateEpsilonTransition(xmlRegParserCtxtPtr ctxt,
1476 xmlRegStatePtr from, xmlRegStatePtr to) {
1477 if (to == NULL) {
1478 to = xmlRegNewState(ctxt);
1479 xmlRegStatePush(ctxt, to);
1480 ctxt->state = to;
1481 }
1482 xmlRegStateAddTrans(ctxt, from, NULL, to, -1, -1);
1483 }
1484
1485 /**
1486 * xmlFAGenerateCountedEpsilonTransition:
1487 * @ctxt: a regexp parser context
1488 * @from: the from state
1489 * @to: the target state or NULL for building a new one
1490 * counter: the counter for that transition
1491 *
1492 */
1493 static void
xmlFAGenerateCountedEpsilonTransition(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr from,xmlRegStatePtr to,int counter)1494 xmlFAGenerateCountedEpsilonTransition(xmlRegParserCtxtPtr ctxt,
1495 xmlRegStatePtr from, xmlRegStatePtr to, int counter) {
1496 if (to == NULL) {
1497 to = xmlRegNewState(ctxt);
1498 xmlRegStatePush(ctxt, to);
1499 ctxt->state = to;
1500 }
1501 xmlRegStateAddTrans(ctxt, from, NULL, to, counter, -1);
1502 }
1503
1504 /**
1505 * xmlFAGenerateCountedTransition:
1506 * @ctxt: a regexp parser context
1507 * @from: the from state
1508 * @to: the target state or NULL for building a new one
1509 * counter: the counter for that transition
1510 *
1511 */
1512 static void
xmlFAGenerateCountedTransition(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr from,xmlRegStatePtr to,int counter)1513 xmlFAGenerateCountedTransition(xmlRegParserCtxtPtr ctxt,
1514 xmlRegStatePtr from, xmlRegStatePtr to, int counter) {
1515 if (to == NULL) {
1516 to = xmlRegNewState(ctxt);
1517 xmlRegStatePush(ctxt, to);
1518 ctxt->state = to;
1519 }
1520 xmlRegStateAddTrans(ctxt, from, NULL, to, -1, counter);
1521 }
1522
1523 /**
1524 * xmlFAGenerateTransitions:
1525 * @ctxt: a regexp parser context
1526 * @from: the from state
1527 * @to: the target state or NULL for building a new one
1528 * @atom: the atom generating the transition
1529 *
1530 * Returns 0 if success and -1 in case of error.
1531 */
1532 static int
xmlFAGenerateTransitions(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr from,xmlRegStatePtr to,xmlRegAtomPtr atom)1533 xmlFAGenerateTransitions(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr from,
1534 xmlRegStatePtr to, xmlRegAtomPtr atom) {
1535 xmlRegStatePtr end;
1536
1537 if (atom == NULL) {
1538 ERROR("genrate transition: atom == NULL");
1539 return(-1);
1540 }
1541 if (atom->type == XML_REGEXP_SUBREG) {
1542 /*
1543 * this is a subexpression handling one should not need to
1544 * create a new node except for XML_REGEXP_QUANT_RANGE.
1545 */
1546 if (xmlRegAtomPush(ctxt, atom) < 0) {
1547 return(-1);
1548 }
1549 if ((to != NULL) && (atom->stop != to) &&
1550 (atom->quant != XML_REGEXP_QUANT_RANGE)) {
1551 /*
1552 * Generate an epsilon transition to link to the target
1553 */
1554 xmlFAGenerateEpsilonTransition(ctxt, atom->stop, to);
1555 #ifdef DV
1556 } else if ((to == NULL) && (atom->quant != XML_REGEXP_QUANT_RANGE) &&
1557 (atom->quant != XML_REGEXP_QUANT_ONCE)) {
1558 to = xmlRegNewState(ctxt);
1559 xmlRegStatePush(ctxt, to);
1560 ctxt->state = to;
1561 xmlFAGenerateEpsilonTransition(ctxt, atom->stop, to);
1562 #endif
1563 }
1564 switch (atom->quant) {
1565 case XML_REGEXP_QUANT_OPT:
1566 atom->quant = XML_REGEXP_QUANT_ONCE;
1567 /*
1568 * transition done to the state after end of atom.
1569 * 1. set transition from atom start to new state
1570 * 2. set transition from atom end to this state.
1571 */
1572 xmlFAGenerateEpsilonTransition(ctxt, atom->start, 0);
1573 xmlFAGenerateEpsilonTransition(ctxt, atom->stop, ctxt->state);
1574 break;
1575 case XML_REGEXP_QUANT_MULT:
1576 atom->quant = XML_REGEXP_QUANT_ONCE;
1577 xmlFAGenerateEpsilonTransition(ctxt, atom->start, atom->stop);
1578 xmlFAGenerateEpsilonTransition(ctxt, atom->stop, atom->start);
1579 break;
1580 case XML_REGEXP_QUANT_PLUS:
1581 atom->quant = XML_REGEXP_QUANT_ONCE;
1582 xmlFAGenerateEpsilonTransition(ctxt, atom->stop, atom->start);
1583 break;
1584 case XML_REGEXP_QUANT_RANGE: {
1585 int counter;
1586 xmlRegStatePtr inter, newstate;
1587
1588 /*
1589 * create the final state now if needed
1590 */
1591 if (to != NULL) {
1592 newstate = to;
1593 } else {
1594 newstate = xmlRegNewState(ctxt);
1595 xmlRegStatePush(ctxt, newstate);
1596 }
1597
1598 /*
1599 * The principle here is to use counted transition
1600 * to avoid explosion in the number of states in the
1601 * graph. This is clearly more complex but should not
1602 * be exploitable at runtime.
1603 */
1604 if ((atom->min == 0) && (atom->start0 == NULL)) {
1605 xmlRegAtomPtr copy;
1606 /*
1607 * duplicate a transition based on atom to count next
1608 * occurences after 1. We cannot loop to atom->start
1609 * directly because we need an epsilon transition to
1610 * newstate.
1611 */
1612 /* ???? For some reason it seems we never reach that
1613 case, I suppose this got optimized out before when
1614 building the automata */
1615 copy = xmlRegCopyAtom(ctxt, atom);
1616 if (copy == NULL)
1617 return(-1);
1618 copy->quant = XML_REGEXP_QUANT_ONCE;
1619 copy->min = 0;
1620 copy->max = 0;
1621
1622 if (xmlFAGenerateTransitions(ctxt, atom->start, NULL, copy)
1623 < 0)
1624 return(-1);
1625 inter = ctxt->state;
1626 counter = xmlRegGetCounter(ctxt);
1627 ctxt->counters[counter].min = atom->min - 1;
1628 ctxt->counters[counter].max = atom->max - 1;
1629 /* count the number of times we see it again */
1630 xmlFAGenerateCountedEpsilonTransition(ctxt, inter,
1631 atom->stop, counter);
1632 /* allow a way out based on the count */
1633 xmlFAGenerateCountedTransition(ctxt, inter,
1634 newstate, counter);
1635 /* and also allow a direct exit for 0 */
1636 xmlFAGenerateEpsilonTransition(ctxt, atom->start,
1637 newstate);
1638 } else {
1639 /*
1640 * either we need the atom at least once or there
1641 * is an atom->start0 allowing to easilly plug the
1642 * epsilon transition.
1643 */
1644 counter = xmlRegGetCounter(ctxt);
1645 ctxt->counters[counter].min = atom->min - 1;
1646 ctxt->counters[counter].max = atom->max - 1;
1647 /* count the number of times we see it again */
1648 xmlFAGenerateCountedEpsilonTransition(ctxt, atom->stop,
1649 atom->start, counter);
1650 /* allow a way out based on the count */
1651 xmlFAGenerateCountedTransition(ctxt, atom->stop,
1652 newstate, counter);
1653 /* and if needed allow a direct exit for 0 */
1654 if (atom->min == 0)
1655 xmlFAGenerateEpsilonTransition(ctxt, atom->start0,
1656 newstate);
1657
1658 }
1659 atom->min = 0;
1660 atom->max = 0;
1661 atom->quant = XML_REGEXP_QUANT_ONCE;
1662 ctxt->state = newstate;
1663 }
1664 default:
1665 break;
1666 }
1667 return(0);
1668 }
1669 if ((atom->min == 0) && (atom->max == 0) &&
1670 (atom->quant == XML_REGEXP_QUANT_RANGE)) {
1671 /*
1672 * we can discard the atom and generate an epsilon transition instead
1673 */
1674 if (to == NULL) {
1675 to = xmlRegNewState(ctxt);
1676 if (to != NULL)
1677 xmlRegStatePush(ctxt, to);
1678 else {
1679 return(-1);
1680 }
1681 }
1682 xmlFAGenerateEpsilonTransition(ctxt, from, to);
1683 ctxt->state = to;
1684 xmlRegFreeAtom(atom);
1685 return(0);
1686 }
1687 if (to == NULL) {
1688 to = xmlRegNewState(ctxt);
1689 if (to != NULL)
1690 xmlRegStatePush(ctxt, to);
1691 else {
1692 return(-1);
1693 }
1694 }
1695 end = to;
1696 if ((atom->quant == XML_REGEXP_QUANT_MULT) ||
1697 (atom->quant == XML_REGEXP_QUANT_PLUS)) {
1698 /*
1699 * Do not pollute the target state by adding transitions from
1700 * it as it is likely to be the shared target of multiple branches.
1701 * So isolate with an epsilon transition.
1702 */
1703 xmlRegStatePtr tmp;
1704
1705 tmp = xmlRegNewState(ctxt);
1706 if (tmp != NULL)
1707 xmlRegStatePush(ctxt, tmp);
1708 else {
1709 return(-1);
1710 }
1711 xmlFAGenerateEpsilonTransition(ctxt, tmp, to);
1712 to = tmp;
1713 }
1714 if (xmlRegAtomPush(ctxt, atom) < 0) {
1715 return(-1);
1716 }
1717 xmlRegStateAddTrans(ctxt, from, atom, to, -1, -1);
1718 ctxt->state = end;
1719 switch (atom->quant) {
1720 case XML_REGEXP_QUANT_OPT:
1721 atom->quant = XML_REGEXP_QUANT_ONCE;
1722 xmlFAGenerateEpsilonTransition(ctxt, from, to);
1723 break;
1724 case XML_REGEXP_QUANT_MULT:
1725 atom->quant = XML_REGEXP_QUANT_ONCE;
1726 xmlFAGenerateEpsilonTransition(ctxt, from, to);
1727 xmlRegStateAddTrans(ctxt, to, atom, to, -1, -1);
1728 break;
1729 case XML_REGEXP_QUANT_PLUS:
1730 atom->quant = XML_REGEXP_QUANT_ONCE;
1731 xmlRegStateAddTrans(ctxt, to, atom, to, -1, -1);
1732 break;
1733 case XML_REGEXP_QUANT_RANGE:
1734 #if DV_test
1735 if (atom->min == 0) {
1736 xmlFAGenerateEpsilonTransition(ctxt, from, to);
1737 }
1738 #endif
1739 break;
1740 default:
1741 break;
1742 }
1743 return(0);
1744 }
1745
1746 /**
1747 * xmlFAReduceEpsilonTransitions:
1748 * @ctxt: a regexp parser context
1749 * @fromnr: the from state
1750 * @tonr: the to state
1751 * @counter: should that transition be associated to a counted
1752 *
1753 */
1754 static void
xmlFAReduceEpsilonTransitions(xmlRegParserCtxtPtr ctxt,int fromnr,int tonr,int counter)1755 xmlFAReduceEpsilonTransitions(xmlRegParserCtxtPtr ctxt, int fromnr,
1756 int tonr, int counter) {
1757 int transnr;
1758 xmlRegStatePtr from;
1759 xmlRegStatePtr to;
1760
1761 #ifdef DEBUG_REGEXP_GRAPH
1762 printf("xmlFAReduceEpsilonTransitions(%d, %d)\n", fromnr, tonr);
1763 #endif
1764 from = ctxt->states[fromnr];
1765 if (from == NULL)
1766 return;
1767 to = ctxt->states[tonr];
1768 if (to == NULL)
1769 return;
1770 if ((to->mark == XML_REGEXP_MARK_START) ||
1771 (to->mark == XML_REGEXP_MARK_VISITED))
1772 return;
1773
1774 to->mark = XML_REGEXP_MARK_VISITED;
1775 if (to->type == XML_REGEXP_FINAL_STATE) {
1776 #ifdef DEBUG_REGEXP_GRAPH
1777 printf("State %d is final, so %d becomes final\n", tonr, fromnr);
1778 #endif
1779 from->type = XML_REGEXP_FINAL_STATE;
1780 }
1781 for (transnr = 0;transnr < to->nbTrans;transnr++) {
1782 if (to->trans[transnr].to < 0)
1783 continue;
1784 if (to->trans[transnr].atom == NULL) {
1785 /*
1786 * Don't remove counted transitions
1787 * Don't loop either
1788 */
1789 if (to->trans[transnr].to != fromnr) {
1790 if (to->trans[transnr].count >= 0) {
1791 int newto = to->trans[transnr].to;
1792
1793 xmlRegStateAddTrans(ctxt, from, NULL,
1794 ctxt->states[newto],
1795 -1, to->trans[transnr].count);
1796 } else {
1797 #ifdef DEBUG_REGEXP_GRAPH
1798 printf("Found epsilon trans %d from %d to %d\n",
1799 transnr, tonr, to->trans[transnr].to);
1800 #endif
1801 if (to->trans[transnr].counter >= 0) {
1802 xmlFAReduceEpsilonTransitions(ctxt, fromnr,
1803 to->trans[transnr].to,
1804 to->trans[transnr].counter);
1805 } else {
1806 xmlFAReduceEpsilonTransitions(ctxt, fromnr,
1807 to->trans[transnr].to,
1808 counter);
1809 }
1810 }
1811 }
1812 } else {
1813 int newto = to->trans[transnr].to;
1814
1815 if (to->trans[transnr].counter >= 0) {
1816 xmlRegStateAddTrans(ctxt, from, to->trans[transnr].atom,
1817 ctxt->states[newto],
1818 to->trans[transnr].counter, -1);
1819 } else {
1820 xmlRegStateAddTrans(ctxt, from, to->trans[transnr].atom,
1821 ctxt->states[newto], counter, -1);
1822 }
1823 }
1824 }
1825 to->mark = XML_REGEXP_MARK_NORMAL;
1826 }
1827
1828 /**
1829 * xmlFAEliminateSimpleEpsilonTransitions:
1830 * @ctxt: a regexp parser context
1831 *
1832 * Eliminating general epsilon transitions can get costly in the general
1833 * algorithm due to the large amount of generated new transitions and
1834 * associated comparisons. However for simple epsilon transition used just
1835 * to separate building blocks when generating the automata this can be
1836 * reduced to state elimination:
1837 * - if there exists an epsilon from X to Y
1838 * - if there is no other transition from X
1839 * then X and Y are semantically equivalent and X can be eliminated
1840 * If X is the start state then make Y the start state, else replace the
1841 * target of all transitions to X by transitions to Y.
1842 */
1843 static void
xmlFAEliminateSimpleEpsilonTransitions(xmlRegParserCtxtPtr ctxt)1844 xmlFAEliminateSimpleEpsilonTransitions(xmlRegParserCtxtPtr ctxt) {
1845 int statenr, i, j, newto;
1846 xmlRegStatePtr state, tmp;
1847
1848 for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
1849 state = ctxt->states[statenr];
1850 if (state == NULL)
1851 continue;
1852 if (state->nbTrans != 1)
1853 continue;
1854 if (state->type == XML_REGEXP_UNREACH_STATE)
1855 continue;
1856 /* is the only transition out a basic transition */
1857 if ((state->trans[0].atom == NULL) &&
1858 (state->trans[0].to >= 0) &&
1859 (state->trans[0].to != statenr) &&
1860 (state->trans[0].counter < 0) &&
1861 (state->trans[0].count < 0)) {
1862 newto = state->trans[0].to;
1863
1864 if (state->type == XML_REGEXP_START_STATE) {
1865 #ifdef DEBUG_REGEXP_GRAPH
1866 printf("Found simple epsilon trans from start %d to %d\n",
1867 statenr, newto);
1868 #endif
1869 } else {
1870 #ifdef DEBUG_REGEXP_GRAPH
1871 printf("Found simple epsilon trans from %d to %d\n",
1872 statenr, newto);
1873 #endif
1874 for (i = 0;i < state->nbTransTo;i++) {
1875 tmp = ctxt->states[state->transTo[i]];
1876 for (j = 0;j < tmp->nbTrans;j++) {
1877 if (tmp->trans[j].to == statenr) {
1878 #ifdef DEBUG_REGEXP_GRAPH
1879 printf("Changed transition %d on %d to go to %d\n",
1880 j, tmp->no, newto);
1881 #endif
1882 tmp->trans[j].to = -1;
1883 xmlRegStateAddTrans(ctxt, tmp, tmp->trans[j].atom,
1884 ctxt->states[newto],
1885 tmp->trans[j].counter,
1886 tmp->trans[j].count);
1887 }
1888 }
1889 }
1890 if (state->type == XML_REGEXP_FINAL_STATE)
1891 ctxt->states[newto]->type = XML_REGEXP_FINAL_STATE;
1892 /* eliminate the transition completely */
1893 state->nbTrans = 0;
1894
1895 state->type = XML_REGEXP_UNREACH_STATE;
1896
1897 }
1898
1899 }
1900 }
1901 }
1902 /**
1903 * xmlFAEliminateEpsilonTransitions:
1904 * @ctxt: a regexp parser context
1905 *
1906 */
1907 static void
xmlFAEliminateEpsilonTransitions(xmlRegParserCtxtPtr ctxt)1908 xmlFAEliminateEpsilonTransitions(xmlRegParserCtxtPtr ctxt) {
1909 int statenr, transnr;
1910 xmlRegStatePtr state;
1911 int has_epsilon;
1912
1913 if (ctxt->states == NULL) return;
1914
1915 /*
1916 * Eliminate simple epsilon transition and the associated unreachable
1917 * states.
1918 */
1919 xmlFAEliminateSimpleEpsilonTransitions(ctxt);
1920 for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
1921 state = ctxt->states[statenr];
1922 if ((state != NULL) && (state->type == XML_REGEXP_UNREACH_STATE)) {
1923 #ifdef DEBUG_REGEXP_GRAPH
1924 printf("Removed unreachable state %d\n", statenr);
1925 #endif
1926 xmlRegFreeState(state);
1927 ctxt->states[statenr] = NULL;
1928 }
1929 }
1930
1931 has_epsilon = 0;
1932
1933 /*
1934 * Build the completed transitions bypassing the epsilons
1935 * Use a marking algorithm to avoid loops
1936 * Mark sink states too.
1937 * Process from the latests states backward to the start when
1938 * there is long cascading epsilon chains this minimize the
1939 * recursions and transition compares when adding the new ones
1940 */
1941 for (statenr = ctxt->nbStates - 1;statenr >= 0;statenr--) {
1942 state = ctxt->states[statenr];
1943 if (state == NULL)
1944 continue;
1945 if ((state->nbTrans == 0) &&
1946 (state->type != XML_REGEXP_FINAL_STATE)) {
1947 state->type = XML_REGEXP_SINK_STATE;
1948 }
1949 for (transnr = 0;transnr < state->nbTrans;transnr++) {
1950 if ((state->trans[transnr].atom == NULL) &&
1951 (state->trans[transnr].to >= 0)) {
1952 if (state->trans[transnr].to == statenr) {
1953 state->trans[transnr].to = -1;
1954 #ifdef DEBUG_REGEXP_GRAPH
1955 printf("Removed loopback epsilon trans %d on %d\n",
1956 transnr, statenr);
1957 #endif
1958 } else if (state->trans[transnr].count < 0) {
1959 int newto = state->trans[transnr].to;
1960
1961 #ifdef DEBUG_REGEXP_GRAPH
1962 printf("Found epsilon trans %d from %d to %d\n",
1963 transnr, statenr, newto);
1964 #endif
1965 has_epsilon = 1;
1966 state->trans[transnr].to = -2;
1967 state->mark = XML_REGEXP_MARK_START;
1968 xmlFAReduceEpsilonTransitions(ctxt, statenr,
1969 newto, state->trans[transnr].counter);
1970 state->mark = XML_REGEXP_MARK_NORMAL;
1971 #ifdef DEBUG_REGEXP_GRAPH
1972 } else {
1973 printf("Found counted transition %d on %d\n",
1974 transnr, statenr);
1975 #endif
1976 }
1977 }
1978 }
1979 }
1980 /*
1981 * Eliminate the epsilon transitions
1982 */
1983 if (has_epsilon) {
1984 for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
1985 state = ctxt->states[statenr];
1986 if (state == NULL)
1987 continue;
1988 for (transnr = 0;transnr < state->nbTrans;transnr++) {
1989 xmlRegTransPtr trans = &(state->trans[transnr]);
1990 if ((trans->atom == NULL) &&
1991 (trans->count < 0) &&
1992 (trans->to >= 0)) {
1993 trans->to = -1;
1994 }
1995 }
1996 }
1997 }
1998
1999 /*
2000 * Use this pass to detect unreachable states too
2001 */
2002 for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
2003 state = ctxt->states[statenr];
2004 if (state != NULL)
2005 state->reached = XML_REGEXP_MARK_NORMAL;
2006 }
2007 state = ctxt->states[0];
2008 if (state != NULL)
2009 state->reached = XML_REGEXP_MARK_START;
2010 while (state != NULL) {
2011 xmlRegStatePtr target = NULL;
2012 state->reached = XML_REGEXP_MARK_VISITED;
2013 /*
2014 * Mark all states reachable from the current reachable state
2015 */
2016 for (transnr = 0;transnr < state->nbTrans;transnr++) {
2017 if ((state->trans[transnr].to >= 0) &&
2018 ((state->trans[transnr].atom != NULL) ||
2019 (state->trans[transnr].count >= 0))) {
2020 int newto = state->trans[transnr].to;
2021
2022 if (ctxt->states[newto] == NULL)
2023 continue;
2024 if (ctxt->states[newto]->reached == XML_REGEXP_MARK_NORMAL) {
2025 ctxt->states[newto]->reached = XML_REGEXP_MARK_START;
2026 target = ctxt->states[newto];
2027 }
2028 }
2029 }
2030
2031 /*
2032 * find the next accessible state not explored
2033 */
2034 if (target == NULL) {
2035 for (statenr = 1;statenr < ctxt->nbStates;statenr++) {
2036 state = ctxt->states[statenr];
2037 if ((state != NULL) && (state->reached ==
2038 XML_REGEXP_MARK_START)) {
2039 target = state;
2040 break;
2041 }
2042 }
2043 }
2044 state = target;
2045 }
2046 for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
2047 state = ctxt->states[statenr];
2048 if ((state != NULL) && (state->reached == XML_REGEXP_MARK_NORMAL)) {
2049 #ifdef DEBUG_REGEXP_GRAPH
2050 printf("Removed unreachable state %d\n", statenr);
2051 #endif
2052 xmlRegFreeState(state);
2053 ctxt->states[statenr] = NULL;
2054 }
2055 }
2056
2057 }
2058
2059 static int
xmlFACompareRanges(xmlRegRangePtr range1,xmlRegRangePtr range2)2060 xmlFACompareRanges(xmlRegRangePtr range1, xmlRegRangePtr range2) {
2061 int ret = 0;
2062
2063 if ((range1->type == XML_REGEXP_RANGES) ||
2064 (range2->type == XML_REGEXP_RANGES) ||
2065 (range2->type == XML_REGEXP_SUBREG) ||
2066 (range1->type == XML_REGEXP_SUBREG) ||
2067 (range1->type == XML_REGEXP_STRING) ||
2068 (range2->type == XML_REGEXP_STRING))
2069 return(-1);
2070
2071 /* put them in order */
2072 if (range1->type > range2->type) {
2073 xmlRegRangePtr tmp;
2074
2075 tmp = range1;
2076 range1 = range2;
2077 range2 = tmp;
2078 }
2079 if ((range1->type == XML_REGEXP_ANYCHAR) ||
2080 (range2->type == XML_REGEXP_ANYCHAR)) {
2081 ret = 1;
2082 } else if ((range1->type == XML_REGEXP_EPSILON) ||
2083 (range2->type == XML_REGEXP_EPSILON)) {
2084 return(0);
2085 } else if (range1->type == range2->type) {
2086 if ((range1->type != XML_REGEXP_CHARVAL) ||
2087 (range1->end < range2->start) ||
2088 (range2->end < range1->start))
2089 ret = 1;
2090 else
2091 ret = 0;
2092 } else if (range1->type == XML_REGEXP_CHARVAL) {
2093 int codepoint;
2094 int neg = 0;
2095
2096 /*
2097 * just check all codepoints in the range for acceptance,
2098 * this is usually way cheaper since done only once at
2099 * compilation than testing over and over at runtime or
2100 * pushing too many states when evaluating.
2101 */
2102 if (((range1->neg == 0) && (range2->neg != 0)) ||
2103 ((range1->neg != 0) && (range2->neg == 0)))
2104 neg = 1;
2105
2106 for (codepoint = range1->start;codepoint <= range1->end ;codepoint++) {
2107 ret = xmlRegCheckCharacterRange(range2->type, codepoint,
2108 0, range2->start, range2->end,
2109 range2->blockName);
2110 if (ret < 0)
2111 return(-1);
2112 if (((neg == 1) && (ret == 0)) ||
2113 ((neg == 0) && (ret == 1)))
2114 return(1);
2115 }
2116 return(0);
2117 } else if ((range1->type == XML_REGEXP_BLOCK_NAME) ||
2118 (range2->type == XML_REGEXP_BLOCK_NAME)) {
2119 if (range1->type == range2->type) {
2120 ret = xmlStrEqual(range1->blockName, range2->blockName);
2121 } else {
2122 /*
2123 * comparing a block range with anything else is way
2124 * too costly, and maintining the table is like too much
2125 * memory too, so let's force the automata to save state
2126 * here.
2127 */
2128 return(1);
2129 }
2130 } else if ((range1->type < XML_REGEXP_LETTER) ||
2131 (range2->type < XML_REGEXP_LETTER)) {
2132 if ((range1->type == XML_REGEXP_ANYSPACE) &&
2133 (range2->type == XML_REGEXP_NOTSPACE))
2134 ret = 0;
2135 else if ((range1->type == XML_REGEXP_INITNAME) &&
2136 (range2->type == XML_REGEXP_NOTINITNAME))
2137 ret = 0;
2138 else if ((range1->type == XML_REGEXP_NAMECHAR) &&
2139 (range2->type == XML_REGEXP_NOTNAMECHAR))
2140 ret = 0;
2141 else if ((range1->type == XML_REGEXP_DECIMAL) &&
2142 (range2->type == XML_REGEXP_NOTDECIMAL))
2143 ret = 0;
2144 else if ((range1->type == XML_REGEXP_REALCHAR) &&
2145 (range2->type == XML_REGEXP_NOTREALCHAR))
2146 ret = 0;
2147 else {
2148 /* same thing to limit complexity */
2149 return(1);
2150 }
2151 } else {
2152 ret = 0;
2153 /* range1->type < range2->type here */
2154 switch (range1->type) {
2155 case XML_REGEXP_LETTER:
2156 /* all disjoint except in the subgroups */
2157 if ((range2->type == XML_REGEXP_LETTER_UPPERCASE) ||
2158 (range2->type == XML_REGEXP_LETTER_LOWERCASE) ||
2159 (range2->type == XML_REGEXP_LETTER_TITLECASE) ||
2160 (range2->type == XML_REGEXP_LETTER_MODIFIER) ||
2161 (range2->type == XML_REGEXP_LETTER_OTHERS))
2162 ret = 1;
2163 break;
2164 case XML_REGEXP_MARK:
2165 if ((range2->type == XML_REGEXP_MARK_NONSPACING) ||
2166 (range2->type == XML_REGEXP_MARK_SPACECOMBINING) ||
2167 (range2->type == XML_REGEXP_MARK_ENCLOSING))
2168 ret = 1;
2169 break;
2170 case XML_REGEXP_NUMBER:
2171 if ((range2->type == XML_REGEXP_NUMBER_DECIMAL) ||
2172 (range2->type == XML_REGEXP_NUMBER_LETTER) ||
2173 (range2->type == XML_REGEXP_NUMBER_OTHERS))
2174 ret = 1;
2175 break;
2176 case XML_REGEXP_PUNCT:
2177 if ((range2->type == XML_REGEXP_PUNCT_CONNECTOR) ||
2178 (range2->type == XML_REGEXP_PUNCT_DASH) ||
2179 (range2->type == XML_REGEXP_PUNCT_OPEN) ||
2180 (range2->type == XML_REGEXP_PUNCT_CLOSE) ||
2181 (range2->type == XML_REGEXP_PUNCT_INITQUOTE) ||
2182 (range2->type == XML_REGEXP_PUNCT_FINQUOTE) ||
2183 (range2->type == XML_REGEXP_PUNCT_OTHERS))
2184 ret = 1;
2185 break;
2186 case XML_REGEXP_SEPAR:
2187 if ((range2->type == XML_REGEXP_SEPAR_SPACE) ||
2188 (range2->type == XML_REGEXP_SEPAR_LINE) ||
2189 (range2->type == XML_REGEXP_SEPAR_PARA))
2190 ret = 1;
2191 break;
2192 case XML_REGEXP_SYMBOL:
2193 if ((range2->type == XML_REGEXP_SYMBOL_MATH) ||
2194 (range2->type == XML_REGEXP_SYMBOL_CURRENCY) ||
2195 (range2->type == XML_REGEXP_SYMBOL_MODIFIER) ||
2196 (range2->type == XML_REGEXP_SYMBOL_OTHERS))
2197 ret = 1;
2198 break;
2199 case XML_REGEXP_OTHER:
2200 if ((range2->type == XML_REGEXP_OTHER_CONTROL) ||
2201 (range2->type == XML_REGEXP_OTHER_FORMAT) ||
2202 (range2->type == XML_REGEXP_OTHER_PRIVATE))
2203 ret = 1;
2204 break;
2205 default:
2206 if ((range2->type >= XML_REGEXP_LETTER) &&
2207 (range2->type < XML_REGEXP_BLOCK_NAME))
2208 ret = 0;
2209 else {
2210 /* safety net ! */
2211 return(1);
2212 }
2213 }
2214 }
2215 if (((range1->neg == 0) && (range2->neg != 0)) ||
2216 ((range1->neg != 0) && (range2->neg == 0)))
2217 ret = !ret;
2218 return(1);
2219 }
2220
2221 /**
2222 * xmlFACompareAtomTypes:
2223 * @type1: an atom type
2224 * @type2: an atom type
2225 *
2226 * Compares two atoms type to check whether they intersect in some ways,
2227 * this is used by xmlFACompareAtoms only
2228 *
2229 * Returns 1 if they may intersect and 0 otherwise
2230 */
2231 static int
xmlFACompareAtomTypes(xmlRegAtomType type1,xmlRegAtomType type2)2232 xmlFACompareAtomTypes(xmlRegAtomType type1, xmlRegAtomType type2) {
2233 if ((type1 == XML_REGEXP_EPSILON) ||
2234 (type1 == XML_REGEXP_CHARVAL) ||
2235 (type1 == XML_REGEXP_RANGES) ||
2236 (type1 == XML_REGEXP_SUBREG) ||
2237 (type1 == XML_REGEXP_STRING) ||
2238 (type1 == XML_REGEXP_ANYCHAR))
2239 return(1);
2240 if ((type2 == XML_REGEXP_EPSILON) ||
2241 (type2 == XML_REGEXP_CHARVAL) ||
2242 (type2 == XML_REGEXP_RANGES) ||
2243 (type2 == XML_REGEXP_SUBREG) ||
2244 (type2 == XML_REGEXP_STRING) ||
2245 (type2 == XML_REGEXP_ANYCHAR))
2246 return(1);
2247
2248 if (type1 == type2) return(1);
2249
2250 /* simplify subsequent compares by making sure type1 < type2 */
2251 if (type1 > type2) {
2252 xmlRegAtomType tmp = type1;
2253 type1 = type2;
2254 type2 = tmp;
2255 }
2256 switch (type1) {
2257 case XML_REGEXP_ANYSPACE: /* \s */
2258 /* can't be a letter, number, mark, pontuation, symbol */
2259 if ((type2 == XML_REGEXP_NOTSPACE) ||
2260 ((type2 >= XML_REGEXP_LETTER) &&
2261 (type2 <= XML_REGEXP_LETTER_OTHERS)) ||
2262 ((type2 >= XML_REGEXP_NUMBER) &&
2263 (type2 <= XML_REGEXP_NUMBER_OTHERS)) ||
2264 ((type2 >= XML_REGEXP_MARK) &&
2265 (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
2266 ((type2 >= XML_REGEXP_PUNCT) &&
2267 (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
2268 ((type2 >= XML_REGEXP_SYMBOL) &&
2269 (type2 <= XML_REGEXP_SYMBOL_OTHERS))
2270 ) return(0);
2271 break;
2272 case XML_REGEXP_NOTSPACE: /* \S */
2273 break;
2274 case XML_REGEXP_INITNAME: /* \l */
2275 /* can't be a number, mark, separator, pontuation, symbol or other */
2276 if ((type2 == XML_REGEXP_NOTINITNAME) ||
2277 ((type2 >= XML_REGEXP_NUMBER) &&
2278 (type2 <= XML_REGEXP_NUMBER_OTHERS)) ||
2279 ((type2 >= XML_REGEXP_MARK) &&
2280 (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
2281 ((type2 >= XML_REGEXP_SEPAR) &&
2282 (type2 <= XML_REGEXP_SEPAR_PARA)) ||
2283 ((type2 >= XML_REGEXP_PUNCT) &&
2284 (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
2285 ((type2 >= XML_REGEXP_SYMBOL) &&
2286 (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
2287 ((type2 >= XML_REGEXP_OTHER) &&
2288 (type2 <= XML_REGEXP_OTHER_NA))
2289 ) return(0);
2290 break;
2291 case XML_REGEXP_NOTINITNAME: /* \L */
2292 break;
2293 case XML_REGEXP_NAMECHAR: /* \c */
2294 /* can't be a mark, separator, pontuation, symbol or other */
2295 if ((type2 == XML_REGEXP_NOTNAMECHAR) ||
2296 ((type2 >= XML_REGEXP_MARK) &&
2297 (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
2298 ((type2 >= XML_REGEXP_PUNCT) &&
2299 (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
2300 ((type2 >= XML_REGEXP_SEPAR) &&
2301 (type2 <= XML_REGEXP_SEPAR_PARA)) ||
2302 ((type2 >= XML_REGEXP_SYMBOL) &&
2303 (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
2304 ((type2 >= XML_REGEXP_OTHER) &&
2305 (type2 <= XML_REGEXP_OTHER_NA))
2306 ) return(0);
2307 break;
2308 case XML_REGEXP_NOTNAMECHAR: /* \C */
2309 break;
2310 case XML_REGEXP_DECIMAL: /* \d */
2311 /* can't be a letter, mark, separator, pontuation, symbol or other */
2312 if ((type2 == XML_REGEXP_NOTDECIMAL) ||
2313 (type2 == XML_REGEXP_REALCHAR) ||
2314 ((type2 >= XML_REGEXP_LETTER) &&
2315 (type2 <= XML_REGEXP_LETTER_OTHERS)) ||
2316 ((type2 >= XML_REGEXP_MARK) &&
2317 (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
2318 ((type2 >= XML_REGEXP_PUNCT) &&
2319 (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
2320 ((type2 >= XML_REGEXP_SEPAR) &&
2321 (type2 <= XML_REGEXP_SEPAR_PARA)) ||
2322 ((type2 >= XML_REGEXP_SYMBOL) &&
2323 (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
2324 ((type2 >= XML_REGEXP_OTHER) &&
2325 (type2 <= XML_REGEXP_OTHER_NA))
2326 )return(0);
2327 break;
2328 case XML_REGEXP_NOTDECIMAL: /* \D */
2329 break;
2330 case XML_REGEXP_REALCHAR: /* \w */
2331 /* can't be a mark, separator, pontuation, symbol or other */
2332 if ((type2 == XML_REGEXP_NOTDECIMAL) ||
2333 ((type2 >= XML_REGEXP_MARK) &&
2334 (type2 <= XML_REGEXP_MARK_ENCLOSING)) ||
2335 ((type2 >= XML_REGEXP_PUNCT) &&
2336 (type2 <= XML_REGEXP_PUNCT_OTHERS)) ||
2337 ((type2 >= XML_REGEXP_SEPAR) &&
2338 (type2 <= XML_REGEXP_SEPAR_PARA)) ||
2339 ((type2 >= XML_REGEXP_SYMBOL) &&
2340 (type2 <= XML_REGEXP_SYMBOL_OTHERS)) ||
2341 ((type2 >= XML_REGEXP_OTHER) &&
2342 (type2 <= XML_REGEXP_OTHER_NA))
2343 )return(0);
2344 break;
2345 case XML_REGEXP_NOTREALCHAR: /* \W */
2346 break;
2347 /*
2348 * at that point we know both type 1 and type2 are from
2349 * character categories are ordered and are different,
2350 * it becomes simple because this is a partition
2351 */
2352 case XML_REGEXP_LETTER:
2353 if (type2 <= XML_REGEXP_LETTER_OTHERS)
2354 return(1);
2355 return(0);
2356 case XML_REGEXP_LETTER_UPPERCASE:
2357 case XML_REGEXP_LETTER_LOWERCASE:
2358 case XML_REGEXP_LETTER_TITLECASE:
2359 case XML_REGEXP_LETTER_MODIFIER:
2360 case XML_REGEXP_LETTER_OTHERS:
2361 return(0);
2362 case XML_REGEXP_MARK:
2363 if (type2 <= XML_REGEXP_MARK_ENCLOSING)
2364 return(1);
2365 return(0);
2366 case XML_REGEXP_MARK_NONSPACING:
2367 case XML_REGEXP_MARK_SPACECOMBINING:
2368 case XML_REGEXP_MARK_ENCLOSING:
2369 return(0);
2370 case XML_REGEXP_NUMBER:
2371 if (type2 <= XML_REGEXP_NUMBER_OTHERS)
2372 return(1);
2373 return(0);
2374 case XML_REGEXP_NUMBER_DECIMAL:
2375 case XML_REGEXP_NUMBER_LETTER:
2376 case XML_REGEXP_NUMBER_OTHERS:
2377 return(0);
2378 case XML_REGEXP_PUNCT:
2379 if (type2 <= XML_REGEXP_PUNCT_OTHERS)
2380 return(1);
2381 return(0);
2382 case XML_REGEXP_PUNCT_CONNECTOR:
2383 case XML_REGEXP_PUNCT_DASH:
2384 case XML_REGEXP_PUNCT_OPEN:
2385 case XML_REGEXP_PUNCT_CLOSE:
2386 case XML_REGEXP_PUNCT_INITQUOTE:
2387 case XML_REGEXP_PUNCT_FINQUOTE:
2388 case XML_REGEXP_PUNCT_OTHERS:
2389 return(0);
2390 case XML_REGEXP_SEPAR:
2391 if (type2 <= XML_REGEXP_SEPAR_PARA)
2392 return(1);
2393 return(0);
2394 case XML_REGEXP_SEPAR_SPACE:
2395 case XML_REGEXP_SEPAR_LINE:
2396 case XML_REGEXP_SEPAR_PARA:
2397 return(0);
2398 case XML_REGEXP_SYMBOL:
2399 if (type2 <= XML_REGEXP_SYMBOL_OTHERS)
2400 return(1);
2401 return(0);
2402 case XML_REGEXP_SYMBOL_MATH:
2403 case XML_REGEXP_SYMBOL_CURRENCY:
2404 case XML_REGEXP_SYMBOL_MODIFIER:
2405 case XML_REGEXP_SYMBOL_OTHERS:
2406 return(0);
2407 case XML_REGEXP_OTHER:
2408 if (type2 <= XML_REGEXP_OTHER_NA)
2409 return(1);
2410 return(0);
2411 case XML_REGEXP_OTHER_CONTROL:
2412 case XML_REGEXP_OTHER_FORMAT:
2413 case XML_REGEXP_OTHER_PRIVATE:
2414 case XML_REGEXP_OTHER_NA:
2415 return(0);
2416 default:
2417 break;
2418 }
2419 return(1);
2420 }
2421
2422 /**
2423 * xmlFAEqualAtoms:
2424 * @atom1: an atom
2425 * @atom2: an atom
2426 *
2427 * Compares two atoms to check whether they are the same exactly
2428 * this is used to remove equivalent transitions
2429 *
2430 * Returns 1 if same and 0 otherwise
2431 */
2432 static int
xmlFAEqualAtoms(xmlRegAtomPtr atom1,xmlRegAtomPtr atom2)2433 xmlFAEqualAtoms(xmlRegAtomPtr atom1, xmlRegAtomPtr atom2) {
2434 int ret = 0;
2435
2436 if (atom1 == atom2)
2437 return(1);
2438 if ((atom1 == NULL) || (atom2 == NULL))
2439 return(0);
2440
2441 if (atom1->type != atom2->type)
2442 return(0);
2443 switch (atom1->type) {
2444 case XML_REGEXP_EPSILON:
2445 ret = 0;
2446 break;
2447 case XML_REGEXP_STRING:
2448 ret = xmlStrEqual((xmlChar *)atom1->valuep,
2449 (xmlChar *)atom2->valuep);
2450 break;
2451 case XML_REGEXP_CHARVAL:
2452 ret = (atom1->codepoint == atom2->codepoint);
2453 break;
2454 case XML_REGEXP_RANGES:
2455 /* too hard to do in the general case */
2456 ret = 0;
2457 default:
2458 break;
2459 }
2460 return(ret);
2461 }
2462
2463 /**
2464 * xmlFACompareAtoms:
2465 * @atom1: an atom
2466 * @atom2: an atom
2467 *
2468 * Compares two atoms to check whether they intersect in some ways,
2469 * this is used by xmlFAComputesDeterminism and xmlFARecurseDeterminism only
2470 *
2471 * Returns 1 if yes and 0 otherwise
2472 */
2473 static int
xmlFACompareAtoms(xmlRegAtomPtr atom1,xmlRegAtomPtr atom2)2474 xmlFACompareAtoms(xmlRegAtomPtr atom1, xmlRegAtomPtr atom2) {
2475 int ret = 1;
2476
2477 if (atom1 == atom2)
2478 return(1);
2479 if ((atom1 == NULL) || (atom2 == NULL))
2480 return(0);
2481
2482 if ((atom1->type == XML_REGEXP_ANYCHAR) ||
2483 (atom2->type == XML_REGEXP_ANYCHAR))
2484 return(1);
2485
2486 if (atom1->type > atom2->type) {
2487 xmlRegAtomPtr tmp;
2488 tmp = atom1;
2489 atom1 = atom2;
2490 atom2 = tmp;
2491 }
2492 if (atom1->type != atom2->type) {
2493 ret = xmlFACompareAtomTypes(atom1->type, atom2->type);
2494 /* if they can't intersect at the type level break now */
2495 if (ret == 0)
2496 return(0);
2497 }
2498 switch (atom1->type) {
2499 case XML_REGEXP_STRING:
2500 ret = xmlRegStrEqualWildcard((xmlChar *)atom1->valuep,
2501 (xmlChar *)atom2->valuep);
2502 break;
2503 case XML_REGEXP_EPSILON:
2504 goto not_determinist;
2505 case XML_REGEXP_CHARVAL:
2506 if (atom2->type == XML_REGEXP_CHARVAL) {
2507 ret = (atom1->codepoint == atom2->codepoint);
2508 } else {
2509 ret = xmlRegCheckCharacter(atom2, atom1->codepoint);
2510 if (ret < 0)
2511 ret = 1;
2512 }
2513 break;
2514 case XML_REGEXP_RANGES:
2515 if (atom2->type == XML_REGEXP_RANGES) {
2516 int i, j, res;
2517 xmlRegRangePtr r1, r2;
2518
2519 /*
2520 * need to check that none of the ranges eventually matches
2521 */
2522 for (i = 0;i < atom1->nbRanges;i++) {
2523 for (j = 0;j < atom2->nbRanges;j++) {
2524 r1 = atom1->ranges[i];
2525 r2 = atom2->ranges[j];
2526 res = xmlFACompareRanges(r1, r2);
2527 if (res == 1) {
2528 ret = 1;
2529 goto done;
2530 }
2531 }
2532 }
2533 ret = 0;
2534 }
2535 break;
2536 default:
2537 goto not_determinist;
2538 }
2539 done:
2540 if (atom1->neg != atom2->neg) {
2541 ret = !ret;
2542 }
2543 if (ret == 0)
2544 return(0);
2545 not_determinist:
2546 return(1);
2547 }
2548
2549 /**
2550 * xmlFARecurseDeterminism:
2551 * @ctxt: a regexp parser context
2552 *
2553 * Check whether the associated regexp is determinist,
2554 * should be called after xmlFAEliminateEpsilonTransitions()
2555 *
2556 */
2557 static int
xmlFARecurseDeterminism(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr state,int to,xmlRegAtomPtr atom)2558 xmlFARecurseDeterminism(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr state,
2559 int to, xmlRegAtomPtr atom) {
2560 int ret = 1;
2561 int res;
2562 int transnr, nbTrans;
2563 xmlRegTransPtr t1;
2564
2565 if (state == NULL)
2566 return(ret);
2567 /*
2568 * don't recurse on transitions potentially added in the course of
2569 * the elimination.
2570 */
2571 nbTrans = state->nbTrans;
2572 for (transnr = 0;transnr < nbTrans;transnr++) {
2573 t1 = &(state->trans[transnr]);
2574 /*
2575 * check transitions conflicting with the one looked at
2576 */
2577 if (t1->atom == NULL) {
2578 if (t1->to < 0)
2579 continue;
2580 res = xmlFARecurseDeterminism(ctxt, ctxt->states[t1->to],
2581 to, atom);
2582 if (res == 0) {
2583 ret = 0;
2584 /* t1->nd = 1; */
2585 }
2586 continue;
2587 }
2588 if (t1->to != to)
2589 continue;
2590 if (xmlFACompareAtoms(t1->atom, atom)) {
2591 ret = 0;
2592 /* mark the transition as non-deterministic */
2593 t1->nd = 1;
2594 }
2595 }
2596 return(ret);
2597 }
2598
2599 /**
2600 * xmlFAComputesDeterminism:
2601 * @ctxt: a regexp parser context
2602 *
2603 * Check whether the associated regexp is determinist,
2604 * should be called after xmlFAEliminateEpsilonTransitions()
2605 *
2606 */
2607 static int
xmlFAComputesDeterminism(xmlRegParserCtxtPtr ctxt)2608 xmlFAComputesDeterminism(xmlRegParserCtxtPtr ctxt) {
2609 int statenr, transnr;
2610 xmlRegStatePtr state;
2611 xmlRegTransPtr t1, t2, last;
2612 int i;
2613 int ret = 1;
2614
2615 #ifdef DEBUG_REGEXP_GRAPH
2616 printf("xmlFAComputesDeterminism\n");
2617 xmlRegPrintCtxt(stdout, ctxt);
2618 #endif
2619 if (ctxt->determinist != -1)
2620 return(ctxt->determinist);
2621
2622 /*
2623 * First cleanup the automata removing cancelled transitions
2624 */
2625 for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
2626 state = ctxt->states[statenr];
2627 if (state == NULL)
2628 continue;
2629 if (state->nbTrans < 2)
2630 continue;
2631 for (transnr = 0;transnr < state->nbTrans;transnr++) {
2632 t1 = &(state->trans[transnr]);
2633 /*
2634 * Determinism checks in case of counted or all transitions
2635 * will have to be handled separately
2636 */
2637 if (t1->atom == NULL) {
2638 /* t1->nd = 1; */
2639 continue;
2640 }
2641 if (t1->to == -1) /* eliminated */
2642 continue;
2643 for (i = 0;i < transnr;i++) {
2644 t2 = &(state->trans[i]);
2645 if (t2->to == -1) /* eliminated */
2646 continue;
2647 if (t2->atom != NULL) {
2648 if (t1->to == t2->to) {
2649 if (xmlFAEqualAtoms(t1->atom, t2->atom))
2650 t2->to = -1; /* eliminated */
2651 }
2652 }
2653 }
2654 }
2655 }
2656
2657 /*
2658 * Check for all states that there aren't 2 transitions
2659 * with the same atom and a different target.
2660 */
2661 for (statenr = 0;statenr < ctxt->nbStates;statenr++) {
2662 state = ctxt->states[statenr];
2663 if (state == NULL)
2664 continue;
2665 if (state->nbTrans < 2)
2666 continue;
2667 last = NULL;
2668 for (transnr = 0;transnr < state->nbTrans;transnr++) {
2669 t1 = &(state->trans[transnr]);
2670 /*
2671 * Determinism checks in case of counted or all transitions
2672 * will have to be handled separately
2673 */
2674 if (t1->atom == NULL) {
2675 continue;
2676 }
2677 if (t1->to == -1) /* eliminated */
2678 continue;
2679 for (i = 0;i < transnr;i++) {
2680 t2 = &(state->trans[i]);
2681 if (t2->to == -1) /* eliminated */
2682 continue;
2683 if (t2->atom != NULL) {
2684 /* not determinist ! */
2685 if (xmlFACompareAtoms(t1->atom, t2->atom)) {
2686 ret = 0;
2687 /* mark the transitions as non-deterministic ones */
2688 t1->nd = 1;
2689 t2->nd = 1;
2690 last = t1;
2691 }
2692 } else if (t1->to != -1) {
2693 /*
2694 * do the closure in case of remaining specific
2695 * epsilon transitions like choices or all
2696 */
2697 ret = xmlFARecurseDeterminism(ctxt, ctxt->states[t1->to],
2698 t2->to, t2->atom);
2699 /* don't shortcut the computation so all non deterministic
2700 transition get marked down
2701 if (ret == 0)
2702 return(0);
2703 */
2704 if (ret == 0) {
2705 t1->nd = 1;
2706 /* t2->nd = 1; */
2707 last = t1;
2708 }
2709 }
2710 }
2711 /* don't shortcut the computation so all non deterministic
2712 transition get marked down
2713 if (ret == 0)
2714 break; */
2715 }
2716
2717 /*
2718 * mark specifically the last non-deterministic transition
2719 * from a state since there is no need to set-up rollback
2720 * from it
2721 */
2722 if (last != NULL) {
2723 last->nd = 2;
2724 }
2725
2726 /* don't shortcut the computation so all non deterministic
2727 transition get marked down
2728 if (ret == 0)
2729 break; */
2730 }
2731
2732 ctxt->determinist = ret;
2733 return(ret);
2734 }
2735
2736 /************************************************************************
2737 * *
2738 * Routines to check input against transition atoms *
2739 * *
2740 ************************************************************************/
2741
2742 static int
xmlRegCheckCharacterRange(xmlRegAtomType type,int codepoint,int neg,int start,int end,const xmlChar * blockName)2743 xmlRegCheckCharacterRange(xmlRegAtomType type, int codepoint, int neg,
2744 int start, int end, const xmlChar *blockName) {
2745 int ret = 0;
2746
2747 switch (type) {
2748 case XML_REGEXP_STRING:
2749 case XML_REGEXP_SUBREG:
2750 case XML_REGEXP_RANGES:
2751 case XML_REGEXP_EPSILON:
2752 return(-1);
2753 case XML_REGEXP_ANYCHAR:
2754 ret = ((codepoint != '\n') && (codepoint != '\r'));
2755 break;
2756 case XML_REGEXP_CHARVAL:
2757 ret = ((codepoint >= start) && (codepoint <= end));
2758 break;
2759 case XML_REGEXP_NOTSPACE:
2760 neg = !neg;
2761 case XML_REGEXP_ANYSPACE:
2762 ret = ((codepoint == '\n') || (codepoint == '\r') ||
2763 (codepoint == '\t') || (codepoint == ' '));
2764 break;
2765 case XML_REGEXP_NOTINITNAME:
2766 neg = !neg;
2767 case XML_REGEXP_INITNAME:
2768 ret = (IS_LETTER(codepoint) ||
2769 (codepoint == '_') || (codepoint == ':'));
2770 break;
2771 case XML_REGEXP_NOTNAMECHAR:
2772 neg = !neg;
2773 case XML_REGEXP_NAMECHAR:
2774 ret = (IS_LETTER(codepoint) || IS_DIGIT(codepoint) ||
2775 (codepoint == '.') || (codepoint == '-') ||
2776 (codepoint == '_') || (codepoint == ':') ||
2777 IS_COMBINING(codepoint) || IS_EXTENDER(codepoint));
2778 break;
2779 case XML_REGEXP_NOTDECIMAL:
2780 neg = !neg;
2781 case XML_REGEXP_DECIMAL:
2782 ret = xmlUCSIsCatNd(codepoint);
2783 break;
2784 case XML_REGEXP_REALCHAR:
2785 neg = !neg;
2786 case XML_REGEXP_NOTREALCHAR:
2787 ret = xmlUCSIsCatP(codepoint);
2788 if (ret == 0)
2789 ret = xmlUCSIsCatZ(codepoint);
2790 if (ret == 0)
2791 ret = xmlUCSIsCatC(codepoint);
2792 break;
2793 case XML_REGEXP_LETTER:
2794 ret = xmlUCSIsCatL(codepoint);
2795 break;
2796 case XML_REGEXP_LETTER_UPPERCASE:
2797 ret = xmlUCSIsCatLu(codepoint);
2798 break;
2799 case XML_REGEXP_LETTER_LOWERCASE:
2800 ret = xmlUCSIsCatLl(codepoint);
2801 break;
2802 case XML_REGEXP_LETTER_TITLECASE:
2803 ret = xmlUCSIsCatLt(codepoint);
2804 break;
2805 case XML_REGEXP_LETTER_MODIFIER:
2806 ret = xmlUCSIsCatLm(codepoint);
2807 break;
2808 case XML_REGEXP_LETTER_OTHERS:
2809 ret = xmlUCSIsCatLo(codepoint);
2810 break;
2811 case XML_REGEXP_MARK:
2812 ret = xmlUCSIsCatM(codepoint);
2813 break;
2814 case XML_REGEXP_MARK_NONSPACING:
2815 ret = xmlUCSIsCatMn(codepoint);
2816 break;
2817 case XML_REGEXP_MARK_SPACECOMBINING:
2818 ret = xmlUCSIsCatMc(codepoint);
2819 break;
2820 case XML_REGEXP_MARK_ENCLOSING:
2821 ret = xmlUCSIsCatMe(codepoint);
2822 break;
2823 case XML_REGEXP_NUMBER:
2824 ret = xmlUCSIsCatN(codepoint);
2825 break;
2826 case XML_REGEXP_NUMBER_DECIMAL:
2827 ret = xmlUCSIsCatNd(codepoint);
2828 break;
2829 case XML_REGEXP_NUMBER_LETTER:
2830 ret = xmlUCSIsCatNl(codepoint);
2831 break;
2832 case XML_REGEXP_NUMBER_OTHERS:
2833 ret = xmlUCSIsCatNo(codepoint);
2834 break;
2835 case XML_REGEXP_PUNCT:
2836 ret = xmlUCSIsCatP(codepoint);
2837 break;
2838 case XML_REGEXP_PUNCT_CONNECTOR:
2839 ret = xmlUCSIsCatPc(codepoint);
2840 break;
2841 case XML_REGEXP_PUNCT_DASH:
2842 ret = xmlUCSIsCatPd(codepoint);
2843 break;
2844 case XML_REGEXP_PUNCT_OPEN:
2845 ret = xmlUCSIsCatPs(codepoint);
2846 break;
2847 case XML_REGEXP_PUNCT_CLOSE:
2848 ret = xmlUCSIsCatPe(codepoint);
2849 break;
2850 case XML_REGEXP_PUNCT_INITQUOTE:
2851 ret = xmlUCSIsCatPi(codepoint);
2852 break;
2853 case XML_REGEXP_PUNCT_FINQUOTE:
2854 ret = xmlUCSIsCatPf(codepoint);
2855 break;
2856 case XML_REGEXP_PUNCT_OTHERS:
2857 ret = xmlUCSIsCatPo(codepoint);
2858 break;
2859 case XML_REGEXP_SEPAR:
2860 ret = xmlUCSIsCatZ(codepoint);
2861 break;
2862 case XML_REGEXP_SEPAR_SPACE:
2863 ret = xmlUCSIsCatZs(codepoint);
2864 break;
2865 case XML_REGEXP_SEPAR_LINE:
2866 ret = xmlUCSIsCatZl(codepoint);
2867 break;
2868 case XML_REGEXP_SEPAR_PARA:
2869 ret = xmlUCSIsCatZp(codepoint);
2870 break;
2871 case XML_REGEXP_SYMBOL:
2872 ret = xmlUCSIsCatS(codepoint);
2873 break;
2874 case XML_REGEXP_SYMBOL_MATH:
2875 ret = xmlUCSIsCatSm(codepoint);
2876 break;
2877 case XML_REGEXP_SYMBOL_CURRENCY:
2878 ret = xmlUCSIsCatSc(codepoint);
2879 break;
2880 case XML_REGEXP_SYMBOL_MODIFIER:
2881 ret = xmlUCSIsCatSk(codepoint);
2882 break;
2883 case XML_REGEXP_SYMBOL_OTHERS:
2884 ret = xmlUCSIsCatSo(codepoint);
2885 break;
2886 case XML_REGEXP_OTHER:
2887 ret = xmlUCSIsCatC(codepoint);
2888 break;
2889 case XML_REGEXP_OTHER_CONTROL:
2890 ret = xmlUCSIsCatCc(codepoint);
2891 break;
2892 case XML_REGEXP_OTHER_FORMAT:
2893 ret = xmlUCSIsCatCf(codepoint);
2894 break;
2895 case XML_REGEXP_OTHER_PRIVATE:
2896 ret = xmlUCSIsCatCo(codepoint);
2897 break;
2898 case XML_REGEXP_OTHER_NA:
2899 /* ret = xmlUCSIsCatCn(codepoint); */
2900 /* Seems it doesn't exist anymore in recent Unicode releases */
2901 ret = 0;
2902 break;
2903 case XML_REGEXP_BLOCK_NAME:
2904 ret = xmlUCSIsBlock(codepoint, (const char *) blockName);
2905 break;
2906 }
2907 if (neg)
2908 return(!ret);
2909 return(ret);
2910 }
2911
2912 static int
xmlRegCheckCharacter(xmlRegAtomPtr atom,int codepoint)2913 xmlRegCheckCharacter(xmlRegAtomPtr atom, int codepoint) {
2914 int i, ret = 0;
2915 xmlRegRangePtr range;
2916
2917 if ((atom == NULL) || (!IS_CHAR(codepoint)))
2918 return(-1);
2919
2920 switch (atom->type) {
2921 case XML_REGEXP_SUBREG:
2922 case XML_REGEXP_EPSILON:
2923 return(-1);
2924 case XML_REGEXP_CHARVAL:
2925 return(codepoint == atom->codepoint);
2926 case XML_REGEXP_RANGES: {
2927 int accept = 0;
2928
2929 for (i = 0;i < atom->nbRanges;i++) {
2930 range = atom->ranges[i];
2931 if (range->neg == 2) {
2932 ret = xmlRegCheckCharacterRange(range->type, codepoint,
2933 0, range->start, range->end,
2934 range->blockName);
2935 if (ret != 0)
2936 return(0); /* excluded char */
2937 } else if (range->neg) {
2938 ret = xmlRegCheckCharacterRange(range->type, codepoint,
2939 0, range->start, range->end,
2940 range->blockName);
2941 if (ret == 0)
2942 accept = 1;
2943 else
2944 return(0);
2945 } else {
2946 ret = xmlRegCheckCharacterRange(range->type, codepoint,
2947 0, range->start, range->end,
2948 range->blockName);
2949 if (ret != 0)
2950 accept = 1; /* might still be excluded */
2951 }
2952 }
2953 return(accept);
2954 }
2955 case XML_REGEXP_STRING:
2956 printf("TODO: XML_REGEXP_STRING\n");
2957 return(-1);
2958 case XML_REGEXP_ANYCHAR:
2959 case XML_REGEXP_ANYSPACE:
2960 case XML_REGEXP_NOTSPACE:
2961 case XML_REGEXP_INITNAME:
2962 case XML_REGEXP_NOTINITNAME:
2963 case XML_REGEXP_NAMECHAR:
2964 case XML_REGEXP_NOTNAMECHAR:
2965 case XML_REGEXP_DECIMAL:
2966 case XML_REGEXP_NOTDECIMAL:
2967 case XML_REGEXP_REALCHAR:
2968 case XML_REGEXP_NOTREALCHAR:
2969 case XML_REGEXP_LETTER:
2970 case XML_REGEXP_LETTER_UPPERCASE:
2971 case XML_REGEXP_LETTER_LOWERCASE:
2972 case XML_REGEXP_LETTER_TITLECASE:
2973 case XML_REGEXP_LETTER_MODIFIER:
2974 case XML_REGEXP_LETTER_OTHERS:
2975 case XML_REGEXP_MARK:
2976 case XML_REGEXP_MARK_NONSPACING:
2977 case XML_REGEXP_MARK_SPACECOMBINING:
2978 case XML_REGEXP_MARK_ENCLOSING:
2979 case XML_REGEXP_NUMBER:
2980 case XML_REGEXP_NUMBER_DECIMAL:
2981 case XML_REGEXP_NUMBER_LETTER:
2982 case XML_REGEXP_NUMBER_OTHERS:
2983 case XML_REGEXP_PUNCT:
2984 case XML_REGEXP_PUNCT_CONNECTOR:
2985 case XML_REGEXP_PUNCT_DASH:
2986 case XML_REGEXP_PUNCT_OPEN:
2987 case XML_REGEXP_PUNCT_CLOSE:
2988 case XML_REGEXP_PUNCT_INITQUOTE:
2989 case XML_REGEXP_PUNCT_FINQUOTE:
2990 case XML_REGEXP_PUNCT_OTHERS:
2991 case XML_REGEXP_SEPAR:
2992 case XML_REGEXP_SEPAR_SPACE:
2993 case XML_REGEXP_SEPAR_LINE:
2994 case XML_REGEXP_SEPAR_PARA:
2995 case XML_REGEXP_SYMBOL:
2996 case XML_REGEXP_SYMBOL_MATH:
2997 case XML_REGEXP_SYMBOL_CURRENCY:
2998 case XML_REGEXP_SYMBOL_MODIFIER:
2999 case XML_REGEXP_SYMBOL_OTHERS:
3000 case XML_REGEXP_OTHER:
3001 case XML_REGEXP_OTHER_CONTROL:
3002 case XML_REGEXP_OTHER_FORMAT:
3003 case XML_REGEXP_OTHER_PRIVATE:
3004 case XML_REGEXP_OTHER_NA:
3005 case XML_REGEXP_BLOCK_NAME:
3006 ret = xmlRegCheckCharacterRange(atom->type, codepoint, 0, 0, 0,
3007 (const xmlChar *)atom->valuep);
3008 if (atom->neg)
3009 ret = !ret;
3010 break;
3011 }
3012 return(ret);
3013 }
3014
3015 /************************************************************************
3016 * *
3017 * Saving and restoring state of an execution context *
3018 * *
3019 ************************************************************************/
3020
3021 #ifdef DEBUG_REGEXP_EXEC
3022 static void
xmlFARegDebugExec(xmlRegExecCtxtPtr exec)3023 xmlFARegDebugExec(xmlRegExecCtxtPtr exec) {
3024 printf("state: %d:%d:idx %d", exec->state->no, exec->transno, exec->index);
3025 if (exec->inputStack != NULL) {
3026 int i;
3027 printf(": ");
3028 for (i = 0;(i < 3) && (i < exec->inputStackNr);i++)
3029 printf("%s ", (const char *)
3030 exec->inputStack[exec->inputStackNr - (i + 1)].value);
3031 } else {
3032 printf(": %s", &(exec->inputString[exec->index]));
3033 }
3034 printf("\n");
3035 }
3036 #endif
3037
3038 static void
xmlFARegExecSave(xmlRegExecCtxtPtr exec)3039 xmlFARegExecSave(xmlRegExecCtxtPtr exec) {
3040 #ifdef DEBUG_REGEXP_EXEC
3041 printf("saving ");
3042 exec->transno++;
3043 xmlFARegDebugExec(exec);
3044 exec->transno--;
3045 #endif
3046 #ifdef MAX_PUSH
3047 if (exec->nbPush > MAX_PUSH) {
3048 return;
3049 }
3050 exec->nbPush++;
3051 #endif
3052
3053 if (exec->maxRollbacks == 0) {
3054 exec->maxRollbacks = 4;
3055 exec->rollbacks = (xmlRegExecRollback *) xmlMalloc(exec->maxRollbacks *
3056 sizeof(xmlRegExecRollback));
3057 if (exec->rollbacks == NULL) {
3058 xmlRegexpErrMemory(NULL, "saving regexp");
3059 exec->maxRollbacks = 0;
3060 return;
3061 }
3062 memset(exec->rollbacks, 0,
3063 exec->maxRollbacks * sizeof(xmlRegExecRollback));
3064 } else if (exec->nbRollbacks >= exec->maxRollbacks) {
3065 xmlRegExecRollback *tmp;
3066 int len = exec->maxRollbacks;
3067
3068 exec->maxRollbacks *= 2;
3069 tmp = (xmlRegExecRollback *) xmlRealloc(exec->rollbacks,
3070 exec->maxRollbacks * sizeof(xmlRegExecRollback));
3071 if (tmp == NULL) {
3072 xmlRegexpErrMemory(NULL, "saving regexp");
3073 exec->maxRollbacks /= 2;
3074 return;
3075 }
3076 exec->rollbacks = tmp;
3077 tmp = &exec->rollbacks[len];
3078 memset(tmp, 0, (exec->maxRollbacks - len) * sizeof(xmlRegExecRollback));
3079 }
3080 exec->rollbacks[exec->nbRollbacks].state = exec->state;
3081 exec->rollbacks[exec->nbRollbacks].index = exec->index;
3082 exec->rollbacks[exec->nbRollbacks].nextbranch = exec->transno + 1;
3083 if (exec->comp->nbCounters > 0) {
3084 if (exec->rollbacks[exec->nbRollbacks].counts == NULL) {
3085 exec->rollbacks[exec->nbRollbacks].counts = (int *)
3086 xmlMalloc(exec->comp->nbCounters * sizeof(int));
3087 if (exec->rollbacks[exec->nbRollbacks].counts == NULL) {
3088 xmlRegexpErrMemory(NULL, "saving regexp");
3089 exec->status = -5;
3090 return;
3091 }
3092 }
3093 memcpy(exec->rollbacks[exec->nbRollbacks].counts, exec->counts,
3094 exec->comp->nbCounters * sizeof(int));
3095 }
3096 exec->nbRollbacks++;
3097 }
3098
3099 static void
xmlFARegExecRollBack(xmlRegExecCtxtPtr exec)3100 xmlFARegExecRollBack(xmlRegExecCtxtPtr exec) {
3101 if (exec->nbRollbacks <= 0) {
3102 exec->status = -1;
3103 #ifdef DEBUG_REGEXP_EXEC
3104 printf("rollback failed on empty stack\n");
3105 #endif
3106 return;
3107 }
3108 exec->nbRollbacks--;
3109 exec->state = exec->rollbacks[exec->nbRollbacks].state;
3110 exec->index = exec->rollbacks[exec->nbRollbacks].index;
3111 exec->transno = exec->rollbacks[exec->nbRollbacks].nextbranch;
3112 if (exec->comp->nbCounters > 0) {
3113 if (exec->rollbacks[exec->nbRollbacks].counts == NULL) {
3114 fprintf(stderr, "exec save: allocation failed");
3115 exec->status = -6;
3116 return;
3117 }
3118 memcpy(exec->counts, exec->rollbacks[exec->nbRollbacks].counts,
3119 exec->comp->nbCounters * sizeof(int));
3120 }
3121
3122 #ifdef DEBUG_REGEXP_EXEC
3123 printf("restored ");
3124 xmlFARegDebugExec(exec);
3125 #endif
3126 }
3127
3128 /************************************************************************
3129 * *
3130 * Verifier, running an input against a compiled regexp *
3131 * *
3132 ************************************************************************/
3133
3134 static int
xmlFARegExec(xmlRegexpPtr comp,const xmlChar * content)3135 xmlFARegExec(xmlRegexpPtr comp, const xmlChar *content) {
3136 xmlRegExecCtxt execval;
3137 xmlRegExecCtxtPtr exec = &execval;
3138 int ret, codepoint = 0, len, deter;
3139
3140 exec->inputString = content;
3141 exec->index = 0;
3142 exec->nbPush = 0;
3143 exec->determinist = 1;
3144 exec->maxRollbacks = 0;
3145 exec->nbRollbacks = 0;
3146 exec->rollbacks = NULL;
3147 exec->status = 0;
3148 exec->comp = comp;
3149 exec->state = comp->states[0];
3150 exec->transno = 0;
3151 exec->transcount = 0;
3152 exec->inputStack = NULL;
3153 exec->inputStackMax = 0;
3154 if (comp->nbCounters > 0) {
3155 exec->counts = (int *) xmlMalloc(comp->nbCounters * sizeof(int));
3156 if (exec->counts == NULL) {
3157 xmlRegexpErrMemory(NULL, "running regexp");
3158 return(-1);
3159 }
3160 memset(exec->counts, 0, comp->nbCounters * sizeof(int));
3161 } else
3162 exec->counts = NULL;
3163 while ((exec->status == 0) &&
3164 ((exec->inputString[exec->index] != 0) ||
3165 ((exec->state != NULL) &&
3166 (exec->state->type != XML_REGEXP_FINAL_STATE)))) {
3167 xmlRegTransPtr trans;
3168 xmlRegAtomPtr atom;
3169
3170 /*
3171 * If end of input on non-terminal state, rollback, however we may
3172 * still have epsilon like transition for counted transitions
3173 * on counters, in that case don't break too early. Additionally,
3174 * if we are working on a range like "AB{0,2}", where B is not present,
3175 * we don't want to break.
3176 */
3177 len = 1;
3178 if ((exec->inputString[exec->index] == 0) && (exec->counts == NULL)) {
3179 /*
3180 * if there is a transition, we must check if
3181 * atom allows minOccurs of 0
3182 */
3183 if (exec->transno < exec->state->nbTrans) {
3184 trans = &exec->state->trans[exec->transno];
3185 if (trans->to >=0) {
3186 atom = trans->atom;
3187 if (!((atom->min == 0) && (atom->max > 0)))
3188 goto rollback;
3189 }
3190 } else
3191 goto rollback;
3192 }
3193
3194 exec->transcount = 0;
3195 for (;exec->transno < exec->state->nbTrans;exec->transno++) {
3196 trans = &exec->state->trans[exec->transno];
3197 if (trans->to < 0)
3198 continue;
3199 atom = trans->atom;
3200 ret = 0;
3201 deter = 1;
3202 if (trans->count >= 0) {
3203 int count;
3204 xmlRegCounterPtr counter;
3205
3206 if (exec->counts == NULL) {
3207 exec->status = -1;
3208 goto error;
3209 }
3210 /*
3211 * A counted transition.
3212 */
3213
3214 count = exec->counts[trans->count];
3215 counter = &exec->comp->counters[trans->count];
3216 #ifdef DEBUG_REGEXP_EXEC
3217 printf("testing count %d: val %d, min %d, max %d\n",
3218 trans->count, count, counter->min, counter->max);
3219 #endif
3220 ret = ((count >= counter->min) && (count <= counter->max));
3221 if ((ret) && (counter->min != counter->max))
3222 deter = 0;
3223 } else if (atom == NULL) {
3224 fprintf(stderr, "epsilon transition left at runtime\n");
3225 exec->status = -2;
3226 break;
3227 } else if (exec->inputString[exec->index] != 0) {
3228 codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len);
3229 ret = xmlRegCheckCharacter(atom, codepoint);
3230 if ((ret == 1) && (atom->min >= 0) && (atom->max > 0)) {
3231 xmlRegStatePtr to = comp->states[trans->to];
3232
3233 /*
3234 * this is a multiple input sequence
3235 * If there is a counter associated increment it now.
3236 * before potentially saving and rollback
3237 * do not increment if the counter is already over the
3238 * maximum limit in which case get to next transition
3239 */
3240 if (trans->counter >= 0) {
3241 xmlRegCounterPtr counter;
3242
3243 if ((exec->counts == NULL) ||
3244 (exec->comp == NULL) ||
3245 (exec->comp->counters == NULL)) {
3246 exec->status = -1;
3247 goto error;
3248 }
3249 counter = &exec->comp->counters[trans->counter];
3250 if (exec->counts[trans->counter] >= counter->max)
3251 continue; /* for loop on transitions */
3252
3253 #ifdef DEBUG_REGEXP_EXEC
3254 printf("Increasing count %d\n", trans->counter);
3255 #endif
3256 exec->counts[trans->counter]++;
3257 }
3258 if (exec->state->nbTrans > exec->transno + 1) {
3259 xmlFARegExecSave(exec);
3260 }
3261 exec->transcount = 1;
3262 do {
3263 /*
3264 * Try to progress as much as possible on the input
3265 */
3266 if (exec->transcount == atom->max) {
3267 break;
3268 }
3269 exec->index += len;
3270 /*
3271 * End of input: stop here
3272 */
3273 if (exec->inputString[exec->index] == 0) {
3274 exec->index -= len;
3275 break;
3276 }
3277 if (exec->transcount >= atom->min) {
3278 int transno = exec->transno;
3279 xmlRegStatePtr state = exec->state;
3280
3281 /*
3282 * The transition is acceptable save it
3283 */
3284 exec->transno = -1; /* trick */
3285 exec->state = to;
3286 xmlFARegExecSave(exec);
3287 exec->transno = transno;
3288 exec->state = state;
3289 }
3290 codepoint = CUR_SCHAR(&(exec->inputString[exec->index]),
3291 len);
3292 ret = xmlRegCheckCharacter(atom, codepoint);
3293 exec->transcount++;
3294 } while (ret == 1);
3295 if (exec->transcount < atom->min)
3296 ret = 0;
3297
3298 /*
3299 * If the last check failed but one transition was found
3300 * possible, rollback
3301 */
3302 if (ret < 0)
3303 ret = 0;
3304 if (ret == 0) {
3305 goto rollback;
3306 }
3307 if (trans->counter >= 0) {
3308 if (exec->counts == NULL) {
3309 exec->status = -1;
3310 goto error;
3311 }
3312 #ifdef DEBUG_REGEXP_EXEC
3313 printf("Decreasing count %d\n", trans->counter);
3314 #endif
3315 exec->counts[trans->counter]--;
3316 }
3317 } else if ((ret == 0) && (atom->min == 0) && (atom->max > 0)) {
3318 /*
3319 * we don't match on the codepoint, but minOccurs of 0
3320 * says that's ok. Setting len to 0 inhibits stepping
3321 * over the codepoint.
3322 */
3323 exec->transcount = 1;
3324 len = 0;
3325 ret = 1;
3326 }
3327 } else if ((atom->min == 0) && (atom->max > 0)) {
3328 /* another spot to match when minOccurs is 0 */
3329 exec->transcount = 1;
3330 len = 0;
3331 ret = 1;
3332 }
3333 if (ret == 1) {
3334 if ((trans->nd == 1) ||
3335 ((trans->count >= 0) && (deter == 0) &&
3336 (exec->state->nbTrans > exec->transno + 1))) {
3337 #ifdef DEBUG_REGEXP_EXEC
3338 if (trans->nd == 1)
3339 printf("Saving on nd transition atom %d for %c at %d\n",
3340 trans->atom->no, codepoint, exec->index);
3341 else
3342 printf("Saving on counted transition count %d for %c at %d\n",
3343 trans->count, codepoint, exec->index);
3344 #endif
3345 xmlFARegExecSave(exec);
3346 }
3347 if (trans->counter >= 0) {
3348 xmlRegCounterPtr counter;
3349
3350 /* make sure we don't go over the counter maximum value */
3351 if ((exec->counts == NULL) ||
3352 (exec->comp == NULL) ||
3353 (exec->comp->counters == NULL)) {
3354 exec->status = -1;
3355 goto error;
3356 }
3357 counter = &exec->comp->counters[trans->counter];
3358 if (exec->counts[trans->counter] >= counter->max)
3359 continue; /* for loop on transitions */
3360 #ifdef DEBUG_REGEXP_EXEC
3361 printf("Increasing count %d\n", trans->counter);
3362 #endif
3363 exec->counts[trans->counter]++;
3364 }
3365 if ((trans->count >= 0) &&
3366 (trans->count < REGEXP_ALL_COUNTER)) {
3367 if (exec->counts == NULL) {
3368 exec->status = -1;
3369 goto error;
3370 }
3371 #ifdef DEBUG_REGEXP_EXEC
3372 printf("resetting count %d on transition\n",
3373 trans->count);
3374 #endif
3375 exec->counts[trans->count] = 0;
3376 }
3377 #ifdef DEBUG_REGEXP_EXEC
3378 printf("entering state %d\n", trans->to);
3379 #endif
3380 exec->state = comp->states[trans->to];
3381 exec->transno = 0;
3382 if (trans->atom != NULL) {
3383 exec->index += len;
3384 }
3385 goto progress;
3386 } else if (ret < 0) {
3387 exec->status = -4;
3388 break;
3389 }
3390 }
3391 if ((exec->transno != 0) || (exec->state->nbTrans == 0)) {
3392 rollback:
3393 /*
3394 * Failed to find a way out
3395 */
3396 exec->determinist = 0;
3397 #ifdef DEBUG_REGEXP_EXEC
3398 printf("rollback from state %d on %d:%c\n", exec->state->no,
3399 codepoint,codepoint);
3400 #endif
3401 xmlFARegExecRollBack(exec);
3402 }
3403 progress:
3404 continue;
3405 }
3406 error:
3407 if (exec->rollbacks != NULL) {
3408 if (exec->counts != NULL) {
3409 int i;
3410
3411 for (i = 0;i < exec->maxRollbacks;i++)
3412 if (exec->rollbacks[i].counts != NULL)
3413 xmlFree(exec->rollbacks[i].counts);
3414 }
3415 xmlFree(exec->rollbacks);
3416 }
3417 if (exec->counts != NULL)
3418 xmlFree(exec->counts);
3419 if (exec->status == 0)
3420 return(1);
3421 if (exec->status == -1) {
3422 if (exec->nbPush > MAX_PUSH)
3423 return(-1);
3424 return(0);
3425 }
3426 return(exec->status);
3427 }
3428
3429 /************************************************************************
3430 * *
3431 * Progressive interface to the verifier one atom at a time *
3432 * *
3433 ************************************************************************/
3434 #ifdef DEBUG_ERR
3435 static void testerr(xmlRegExecCtxtPtr exec);
3436 #endif
3437
3438 /**
3439 * xmlRegNewExecCtxt:
3440 * @comp: a precompiled regular expression
3441 * @callback: a callback function used for handling progresses in the
3442 * automata matching phase
3443 * @data: the context data associated to the callback in this context
3444 *
3445 * Build a context used for progressive evaluation of a regexp.
3446 *
3447 * Returns the new context
3448 */
3449 xmlRegExecCtxtPtr
xmlRegNewExecCtxt(xmlRegexpPtr comp,xmlRegExecCallbacks callback,void * data)3450 xmlRegNewExecCtxt(xmlRegexpPtr comp, xmlRegExecCallbacks callback, void *data) {
3451 xmlRegExecCtxtPtr exec;
3452
3453 if (comp == NULL)
3454 return(NULL);
3455 if ((comp->compact == NULL) && (comp->states == NULL))
3456 return(NULL);
3457 exec = (xmlRegExecCtxtPtr) xmlMalloc(sizeof(xmlRegExecCtxt));
3458 if (exec == NULL) {
3459 xmlRegexpErrMemory(NULL, "creating execution context");
3460 return(NULL);
3461 }
3462 memset(exec, 0, sizeof(xmlRegExecCtxt));
3463 exec->inputString = NULL;
3464 exec->index = 0;
3465 exec->determinist = 1;
3466 exec->maxRollbacks = 0;
3467 exec->nbRollbacks = 0;
3468 exec->rollbacks = NULL;
3469 exec->status = 0;
3470 exec->comp = comp;
3471 if (comp->compact == NULL)
3472 exec->state = comp->states[0];
3473 exec->transno = 0;
3474 exec->transcount = 0;
3475 exec->callback = callback;
3476 exec->data = data;
3477 if (comp->nbCounters > 0) {
3478 /*
3479 * For error handling, exec->counts is allocated twice the size
3480 * the second half is used to store the data in case of rollback
3481 */
3482 exec->counts = (int *) xmlMalloc(comp->nbCounters * sizeof(int)
3483 * 2);
3484 if (exec->counts == NULL) {
3485 xmlRegexpErrMemory(NULL, "creating execution context");
3486 xmlFree(exec);
3487 return(NULL);
3488 }
3489 memset(exec->counts, 0, comp->nbCounters * sizeof(int) * 2);
3490 exec->errCounts = &exec->counts[comp->nbCounters];
3491 } else {
3492 exec->counts = NULL;
3493 exec->errCounts = NULL;
3494 }
3495 exec->inputStackMax = 0;
3496 exec->inputStackNr = 0;
3497 exec->inputStack = NULL;
3498 exec->errStateNo = -1;
3499 exec->errString = NULL;
3500 exec->nbPush = 0;
3501 return(exec);
3502 }
3503
3504 /**
3505 * xmlRegFreeExecCtxt:
3506 * @exec: a regular expression evaulation context
3507 *
3508 * Free the structures associated to a regular expression evaulation context.
3509 */
3510 void
xmlRegFreeExecCtxt(xmlRegExecCtxtPtr exec)3511 xmlRegFreeExecCtxt(xmlRegExecCtxtPtr exec) {
3512 if (exec == NULL)
3513 return;
3514
3515 if (exec->rollbacks != NULL) {
3516 if (exec->counts != NULL) {
3517 int i;
3518
3519 for (i = 0;i < exec->maxRollbacks;i++)
3520 if (exec->rollbacks[i].counts != NULL)
3521 xmlFree(exec->rollbacks[i].counts);
3522 }
3523 xmlFree(exec->rollbacks);
3524 }
3525 if (exec->counts != NULL)
3526 xmlFree(exec->counts);
3527 if (exec->inputStack != NULL) {
3528 int i;
3529
3530 for (i = 0;i < exec->inputStackNr;i++) {
3531 if (exec->inputStack[i].value != NULL)
3532 xmlFree(exec->inputStack[i].value);
3533 }
3534 xmlFree(exec->inputStack);
3535 }
3536 if (exec->errString != NULL)
3537 xmlFree(exec->errString);
3538 xmlFree(exec);
3539 }
3540
3541 static void
xmlFARegExecSaveInputString(xmlRegExecCtxtPtr exec,const xmlChar * value,void * data)3542 xmlFARegExecSaveInputString(xmlRegExecCtxtPtr exec, const xmlChar *value,
3543 void *data) {
3544 #ifdef DEBUG_PUSH
3545 printf("saving value: %d:%s\n", exec->inputStackNr, value);
3546 #endif
3547 if (exec->inputStackMax == 0) {
3548 exec->inputStackMax = 4;
3549 exec->inputStack = (xmlRegInputTokenPtr)
3550 xmlMalloc(exec->inputStackMax * sizeof(xmlRegInputToken));
3551 if (exec->inputStack == NULL) {
3552 xmlRegexpErrMemory(NULL, "pushing input string");
3553 exec->inputStackMax = 0;
3554 return;
3555 }
3556 } else if (exec->inputStackNr + 1 >= exec->inputStackMax) {
3557 xmlRegInputTokenPtr tmp;
3558
3559 exec->inputStackMax *= 2;
3560 tmp = (xmlRegInputTokenPtr) xmlRealloc(exec->inputStack,
3561 exec->inputStackMax * sizeof(xmlRegInputToken));
3562 if (tmp == NULL) {
3563 xmlRegexpErrMemory(NULL, "pushing input string");
3564 exec->inputStackMax /= 2;
3565 return;
3566 }
3567 exec->inputStack = tmp;
3568 }
3569 exec->inputStack[exec->inputStackNr].value = xmlStrdup(value);
3570 exec->inputStack[exec->inputStackNr].data = data;
3571 exec->inputStackNr++;
3572 exec->inputStack[exec->inputStackNr].value = NULL;
3573 exec->inputStack[exec->inputStackNr].data = NULL;
3574 }
3575
3576 /**
3577 * xmlRegStrEqualWildcard:
3578 * @expStr: the string to be evaluated
3579 * @valStr: the validation string
3580 *
3581 * Checks if both strings are equal or have the same content. "*"
3582 * can be used as a wildcard in @valStr; "|" is used as a seperator of
3583 * substrings in both @expStr and @valStr.
3584 *
3585 * Returns 1 if the comparison is satisfied and the number of substrings
3586 * is equal, 0 otherwise.
3587 */
3588
3589 static int
xmlRegStrEqualWildcard(const xmlChar * expStr,const xmlChar * valStr)3590 xmlRegStrEqualWildcard(const xmlChar *expStr, const xmlChar *valStr) {
3591 if (expStr == valStr) return(1);
3592 if (expStr == NULL) return(0);
3593 if (valStr == NULL) return(0);
3594 do {
3595 /*
3596 * Eval if we have a wildcard for the current item.
3597 */
3598 if (*expStr != *valStr) {
3599 /* if one of them starts with a wildcard make valStr be it */
3600 if (*valStr == '*') {
3601 const xmlChar *tmp;
3602
3603 tmp = valStr;
3604 valStr = expStr;
3605 expStr = tmp;
3606 }
3607 if ((*valStr != 0) && (*expStr != 0) && (*expStr++ == '*')) {
3608 do {
3609 if (*valStr == XML_REG_STRING_SEPARATOR)
3610 break;
3611 valStr++;
3612 } while (*valStr != 0);
3613 continue;
3614 } else
3615 return(0);
3616 }
3617 expStr++;
3618 valStr++;
3619 } while (*valStr != 0);
3620 if (*expStr != 0)
3621 return (0);
3622 else
3623 return (1);
3624 }
3625
3626 /**
3627 * xmlRegCompactPushString:
3628 * @exec: a regexp execution context
3629 * @comp: the precompiled exec with a compact table
3630 * @value: a string token input
3631 * @data: data associated to the token to reuse in callbacks
3632 *
3633 * Push one input token in the execution context
3634 *
3635 * Returns: 1 if the regexp reached a final state, 0 if non-final, and
3636 * a negative value in case of error.
3637 */
3638 static int
xmlRegCompactPushString(xmlRegExecCtxtPtr exec,xmlRegexpPtr comp,const xmlChar * value,void * data)3639 xmlRegCompactPushString(xmlRegExecCtxtPtr exec,
3640 xmlRegexpPtr comp,
3641 const xmlChar *value,
3642 void *data) {
3643 int state = exec->index;
3644 int i, target;
3645
3646 if ((comp == NULL) || (comp->compact == NULL) || (comp->stringMap == NULL))
3647 return(-1);
3648
3649 if (value == NULL) {
3650 /*
3651 * are we at a final state ?
3652 */
3653 if (comp->compact[state * (comp->nbstrings + 1)] ==
3654 XML_REGEXP_FINAL_STATE)
3655 return(1);
3656 return(0);
3657 }
3658
3659 #ifdef DEBUG_PUSH
3660 printf("value pushed: %s\n", value);
3661 #endif
3662
3663 /*
3664 * Examine all outside transitions from current state
3665 */
3666 for (i = 0;i < comp->nbstrings;i++) {
3667 target = comp->compact[state * (comp->nbstrings + 1) + i + 1];
3668 if ((target > 0) && (target <= comp->nbstates)) {
3669 target--; /* to avoid 0 */
3670 if (xmlRegStrEqualWildcard(comp->stringMap[i], value)) {
3671 exec->index = target;
3672 if ((exec->callback != NULL) && (comp->transdata != NULL)) {
3673 exec->callback(exec->data, value,
3674 comp->transdata[state * comp->nbstrings + i], data);
3675 }
3676 #ifdef DEBUG_PUSH
3677 printf("entering state %d\n", target);
3678 #endif
3679 if (comp->compact[target * (comp->nbstrings + 1)] ==
3680 XML_REGEXP_SINK_STATE)
3681 goto error;
3682
3683 if (comp->compact[target * (comp->nbstrings + 1)] ==
3684 XML_REGEXP_FINAL_STATE)
3685 return(1);
3686 return(0);
3687 }
3688 }
3689 }
3690 /*
3691 * Failed to find an exit transition out from current state for the
3692 * current token
3693 */
3694 #ifdef DEBUG_PUSH
3695 printf("failed to find a transition for %s on state %d\n", value, state);
3696 #endif
3697 error:
3698 if (exec->errString != NULL)
3699 xmlFree(exec->errString);
3700 exec->errString = xmlStrdup(value);
3701 exec->errStateNo = state;
3702 exec->status = -1;
3703 #ifdef DEBUG_ERR
3704 testerr(exec);
3705 #endif
3706 return(-1);
3707 }
3708
3709 /**
3710 * xmlRegExecPushStringInternal:
3711 * @exec: a regexp execution context or NULL to indicate the end
3712 * @value: a string token input
3713 * @data: data associated to the token to reuse in callbacks
3714 * @compound: value was assembled from 2 strings
3715 *
3716 * Push one input token in the execution context
3717 *
3718 * Returns: 1 if the regexp reached a final state, 0 if non-final, and
3719 * a negative value in case of error.
3720 */
3721 static int
xmlRegExecPushStringInternal(xmlRegExecCtxtPtr exec,const xmlChar * value,void * data,int compound)3722 xmlRegExecPushStringInternal(xmlRegExecCtxtPtr exec, const xmlChar *value,
3723 void *data, int compound) {
3724 xmlRegTransPtr trans;
3725 xmlRegAtomPtr atom;
3726 int ret;
3727 int final = 0;
3728 int progress = 1;
3729
3730 if (exec == NULL)
3731 return(-1);
3732 if (exec->comp == NULL)
3733 return(-1);
3734 if (exec->status != 0)
3735 return(exec->status);
3736
3737 if (exec->comp->compact != NULL)
3738 return(xmlRegCompactPushString(exec, exec->comp, value, data));
3739
3740 if (value == NULL) {
3741 if (exec->state->type == XML_REGEXP_FINAL_STATE)
3742 return(1);
3743 final = 1;
3744 }
3745
3746 #ifdef DEBUG_PUSH
3747 printf("value pushed: %s\n", value);
3748 #endif
3749 /*
3750 * If we have an active rollback stack push the new value there
3751 * and get back to where we were left
3752 */
3753 if ((value != NULL) && (exec->inputStackNr > 0)) {
3754 xmlFARegExecSaveInputString(exec, value, data);
3755 value = exec->inputStack[exec->index].value;
3756 data = exec->inputStack[exec->index].data;
3757 #ifdef DEBUG_PUSH
3758 printf("value loaded: %s\n", value);
3759 #endif
3760 }
3761
3762 while ((exec->status == 0) &&
3763 ((value != NULL) ||
3764 ((final == 1) &&
3765 (exec->state->type != XML_REGEXP_FINAL_STATE)))) {
3766
3767 /*
3768 * End of input on non-terminal state, rollback, however we may
3769 * still have epsilon like transition for counted transitions
3770 * on counters, in that case don't break too early.
3771 */
3772 if ((value == NULL) && (exec->counts == NULL))
3773 goto rollback;
3774
3775 exec->transcount = 0;
3776 for (;exec->transno < exec->state->nbTrans;exec->transno++) {
3777 trans = &exec->state->trans[exec->transno];
3778 if (trans->to < 0)
3779 continue;
3780 atom = trans->atom;
3781 ret = 0;
3782 if (trans->count == REGEXP_ALL_LAX_COUNTER) {
3783 int i;
3784 int count;
3785 xmlRegTransPtr t;
3786 xmlRegCounterPtr counter;
3787
3788 ret = 0;
3789
3790 #ifdef DEBUG_PUSH
3791 printf("testing all lax %d\n", trans->count);
3792 #endif
3793 /*
3794 * Check all counted transitions from the current state
3795 */
3796 if ((value == NULL) && (final)) {
3797 ret = 1;
3798 } else if (value != NULL) {
3799 for (i = 0;i < exec->state->nbTrans;i++) {
3800 t = &exec->state->trans[i];
3801 if ((t->counter < 0) || (t == trans))
3802 continue;
3803 counter = &exec->comp->counters[t->counter];
3804 count = exec->counts[t->counter];
3805 if ((count < counter->max) &&
3806 (t->atom != NULL) &&
3807 (xmlStrEqual(value, t->atom->valuep))) {
3808 ret = 0;
3809 break;
3810 }
3811 if ((count >= counter->min) &&
3812 (count < counter->max) &&
3813 (t->atom != NULL) &&
3814 (xmlStrEqual(value, t->atom->valuep))) {
3815 ret = 1;
3816 break;
3817 }
3818 }
3819 }
3820 } else if (trans->count == REGEXP_ALL_COUNTER) {
3821 int i;
3822 int count;
3823 xmlRegTransPtr t;
3824 xmlRegCounterPtr counter;
3825
3826 ret = 1;
3827
3828 #ifdef DEBUG_PUSH
3829 printf("testing all %d\n", trans->count);
3830 #endif
3831 /*
3832 * Check all counted transitions from the current state
3833 */
3834 for (i = 0;i < exec->state->nbTrans;i++) {
3835 t = &exec->state->trans[i];
3836 if ((t->counter < 0) || (t == trans))
3837 continue;
3838 counter = &exec->comp->counters[t->counter];
3839 count = exec->counts[t->counter];
3840 if ((count < counter->min) || (count > counter->max)) {
3841 ret = 0;
3842 break;
3843 }
3844 }
3845 } else if (trans->count >= 0) {
3846 int count;
3847 xmlRegCounterPtr counter;
3848
3849 /*
3850 * A counted transition.
3851 */
3852
3853 count = exec->counts[trans->count];
3854 counter = &exec->comp->counters[trans->count];
3855 #ifdef DEBUG_PUSH
3856 printf("testing count %d: val %d, min %d, max %d\n",
3857 trans->count, count, counter->min, counter->max);
3858 #endif
3859 ret = ((count >= counter->min) && (count <= counter->max));
3860 } else if (atom == NULL) {
3861 fprintf(stderr, "epsilon transition left at runtime\n");
3862 exec->status = -2;
3863 break;
3864 } else if (value != NULL) {
3865 ret = xmlRegStrEqualWildcard(atom->valuep, value);
3866 if (atom->neg) {
3867 ret = !ret;
3868 if (!compound)
3869 ret = 0;
3870 }
3871 if ((ret == 1) && (trans->counter >= 0)) {
3872 xmlRegCounterPtr counter;
3873 int count;
3874
3875 count = exec->counts[trans->counter];
3876 counter = &exec->comp->counters[trans->counter];
3877 if (count >= counter->max)
3878 ret = 0;
3879 }
3880
3881 if ((ret == 1) && (atom->min > 0) && (atom->max > 0)) {
3882 xmlRegStatePtr to = exec->comp->states[trans->to];
3883
3884 /*
3885 * this is a multiple input sequence
3886 */
3887 if (exec->state->nbTrans > exec->transno + 1) {
3888 if (exec->inputStackNr <= 0) {
3889 xmlFARegExecSaveInputString(exec, value, data);
3890 }
3891 xmlFARegExecSave(exec);
3892 }
3893 exec->transcount = 1;
3894 do {
3895 /*
3896 * Try to progress as much as possible on the input
3897 */
3898 if (exec->transcount == atom->max) {
3899 break;
3900 }
3901 exec->index++;
3902 value = exec->inputStack[exec->index].value;
3903 data = exec->inputStack[exec->index].data;
3904 #ifdef DEBUG_PUSH
3905 printf("value loaded: %s\n", value);
3906 #endif
3907
3908 /*
3909 * End of input: stop here
3910 */
3911 if (value == NULL) {
3912 exec->index --;
3913 break;
3914 }
3915 if (exec->transcount >= atom->min) {
3916 int transno = exec->transno;
3917 xmlRegStatePtr state = exec->state;
3918
3919 /*
3920 * The transition is acceptable save it
3921 */
3922 exec->transno = -1; /* trick */
3923 exec->state = to;
3924 if (exec->inputStackNr <= 0) {
3925 xmlFARegExecSaveInputString(exec, value, data);
3926 }
3927 xmlFARegExecSave(exec);
3928 exec->transno = transno;
3929 exec->state = state;
3930 }
3931 ret = xmlStrEqual(value, atom->valuep);
3932 exec->transcount++;
3933 } while (ret == 1);
3934 if (exec->transcount < atom->min)
3935 ret = 0;
3936
3937 /*
3938 * If the last check failed but one transition was found
3939 * possible, rollback
3940 */
3941 if (ret < 0)
3942 ret = 0;
3943 if (ret == 0) {
3944 goto rollback;
3945 }
3946 }
3947 }
3948 if (ret == 1) {
3949 if ((exec->callback != NULL) && (atom != NULL) &&
3950 (data != NULL)) {
3951 exec->callback(exec->data, atom->valuep,
3952 atom->data, data);
3953 }
3954 if (exec->state->nbTrans > exec->transno + 1) {
3955 if (exec->inputStackNr <= 0) {
3956 xmlFARegExecSaveInputString(exec, value, data);
3957 }
3958 xmlFARegExecSave(exec);
3959 }
3960 if (trans->counter >= 0) {
3961 #ifdef DEBUG_PUSH
3962 printf("Increasing count %d\n", trans->counter);
3963 #endif
3964 exec->counts[trans->counter]++;
3965 }
3966 if ((trans->count >= 0) &&
3967 (trans->count < REGEXP_ALL_COUNTER)) {
3968 #ifdef DEBUG_REGEXP_EXEC
3969 printf("resetting count %d on transition\n",
3970 trans->count);
3971 #endif
3972 exec->counts[trans->count] = 0;
3973 }
3974 #ifdef DEBUG_PUSH
3975 printf("entering state %d\n", trans->to);
3976 #endif
3977 if ((exec->comp->states[trans->to] != NULL) &&
3978 (exec->comp->states[trans->to]->type ==
3979 XML_REGEXP_SINK_STATE)) {
3980 /*
3981 * entering a sink state, save the current state as error
3982 * state.
3983 */
3984 if (exec->errString != NULL)
3985 xmlFree(exec->errString);
3986 exec->errString = xmlStrdup(value);
3987 exec->errState = exec->state;
3988 memcpy(exec->errCounts, exec->counts,
3989 exec->comp->nbCounters * sizeof(int));
3990 }
3991 exec->state = exec->comp->states[trans->to];
3992 exec->transno = 0;
3993 if (trans->atom != NULL) {
3994 if (exec->inputStack != NULL) {
3995 exec->index++;
3996 if (exec->index < exec->inputStackNr) {
3997 value = exec->inputStack[exec->index].value;
3998 data = exec->inputStack[exec->index].data;
3999 #ifdef DEBUG_PUSH
4000 printf("value loaded: %s\n", value);
4001 #endif
4002 } else {
4003 value = NULL;
4004 data = NULL;
4005 #ifdef DEBUG_PUSH
4006 printf("end of input\n");
4007 #endif
4008 }
4009 } else {
4010 value = NULL;
4011 data = NULL;
4012 #ifdef DEBUG_PUSH
4013 printf("end of input\n");
4014 #endif
4015 }
4016 }
4017 goto progress;
4018 } else if (ret < 0) {
4019 exec->status = -4;
4020 break;
4021 }
4022 }
4023 if ((exec->transno != 0) || (exec->state->nbTrans == 0)) {
4024 rollback:
4025 /*
4026 * if we didn't yet rollback on the current input
4027 * store the current state as the error state.
4028 */
4029 if ((progress) && (exec->state != NULL) &&
4030 (exec->state->type != XML_REGEXP_SINK_STATE)) {
4031 progress = 0;
4032 if (exec->errString != NULL)
4033 xmlFree(exec->errString);
4034 exec->errString = xmlStrdup(value);
4035 exec->errState = exec->state;
4036 memcpy(exec->errCounts, exec->counts,
4037 exec->comp->nbCounters * sizeof(int));
4038 }
4039
4040 /*
4041 * Failed to find a way out
4042 */
4043 exec->determinist = 0;
4044 xmlFARegExecRollBack(exec);
4045 if (exec->status == 0) {
4046 value = exec->inputStack[exec->index].value;
4047 data = exec->inputStack[exec->index].data;
4048 #ifdef DEBUG_PUSH
4049 printf("value loaded: %s\n", value);
4050 #endif
4051 }
4052 }
4053 continue;
4054 progress:
4055 progress = 1;
4056 continue;
4057 }
4058 if (exec->status == 0) {
4059 return(exec->state->type == XML_REGEXP_FINAL_STATE);
4060 }
4061 #ifdef DEBUG_ERR
4062 if (exec->status < 0) {
4063 testerr(exec);
4064 }
4065 #endif
4066 return(exec->status);
4067 }
4068
4069 /**
4070 * xmlRegExecPushString:
4071 * @exec: a regexp execution context or NULL to indicate the end
4072 * @value: a string token input
4073 * @data: data associated to the token to reuse in callbacks
4074 *
4075 * Push one input token in the execution context
4076 *
4077 * Returns: 1 if the regexp reached a final state, 0 if non-final, and
4078 * a negative value in case of error.
4079 */
4080 int
xmlRegExecPushString(xmlRegExecCtxtPtr exec,const xmlChar * value,void * data)4081 xmlRegExecPushString(xmlRegExecCtxtPtr exec, const xmlChar *value,
4082 void *data) {
4083 return(xmlRegExecPushStringInternal(exec, value, data, 0));
4084 }
4085
4086 /**
4087 * xmlRegExecPushString2:
4088 * @exec: a regexp execution context or NULL to indicate the end
4089 * @value: the first string token input
4090 * @value2: the second string token input
4091 * @data: data associated to the token to reuse in callbacks
4092 *
4093 * Push one input token in the execution context
4094 *
4095 * Returns: 1 if the regexp reached a final state, 0 if non-final, and
4096 * a negative value in case of error.
4097 */
4098 int
xmlRegExecPushString2(xmlRegExecCtxtPtr exec,const xmlChar * value,const xmlChar * value2,void * data)4099 xmlRegExecPushString2(xmlRegExecCtxtPtr exec, const xmlChar *value,
4100 const xmlChar *value2, void *data) {
4101 xmlChar buf[150];
4102 int lenn, lenp, ret;
4103 xmlChar *str;
4104
4105 if (exec == NULL)
4106 return(-1);
4107 if (exec->comp == NULL)
4108 return(-1);
4109 if (exec->status != 0)
4110 return(exec->status);
4111
4112 if (value2 == NULL)
4113 return(xmlRegExecPushString(exec, value, data));
4114
4115 lenn = strlen((char *) value2);
4116 lenp = strlen((char *) value);
4117
4118 if (150 < lenn + lenp + 2) {
4119 str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
4120 if (str == NULL) {
4121 exec->status = -1;
4122 return(-1);
4123 }
4124 } else {
4125 str = buf;
4126 }
4127 memcpy(&str[0], value, lenp);
4128 str[lenp] = XML_REG_STRING_SEPARATOR;
4129 memcpy(&str[lenp + 1], value2, lenn);
4130 str[lenn + lenp + 1] = 0;
4131
4132 if (exec->comp->compact != NULL)
4133 ret = xmlRegCompactPushString(exec, exec->comp, str, data);
4134 else
4135 ret = xmlRegExecPushStringInternal(exec, str, data, 1);
4136
4137 if (str != buf)
4138 xmlFree(str);
4139 return(ret);
4140 }
4141
4142 /**
4143 * xmlRegExecGetValues:
4144 * @exec: a regexp execution context
4145 * @err: error extraction or normal one
4146 * @nbval: pointer to the number of accepted values IN/OUT
4147 * @nbneg: return number of negative transitions
4148 * @values: pointer to the array of acceptable values
4149 * @terminal: return value if this was a terminal state
4150 *
4151 * Extract informations from the regexp execution, internal routine to
4152 * implement xmlRegExecNextValues() and xmlRegExecErrInfo()
4153 *
4154 * Returns: 0 in case of success or -1 in case of error.
4155 */
4156 static int
xmlRegExecGetValues(xmlRegExecCtxtPtr exec,int err,int * nbval,int * nbneg,xmlChar ** values,int * terminal)4157 xmlRegExecGetValues(xmlRegExecCtxtPtr exec, int err,
4158 int *nbval, int *nbneg,
4159 xmlChar **values, int *terminal) {
4160 int maxval;
4161 int nb = 0;
4162
4163 if ((exec == NULL) || (nbval == NULL) || (nbneg == NULL) ||
4164 (values == NULL) || (*nbval <= 0))
4165 return(-1);
4166
4167 maxval = *nbval;
4168 *nbval = 0;
4169 *nbneg = 0;
4170 if ((exec->comp != NULL) && (exec->comp->compact != NULL)) {
4171 xmlRegexpPtr comp;
4172 int target, i, state;
4173
4174 comp = exec->comp;
4175
4176 if (err) {
4177 if (exec->errStateNo == -1) return(-1);
4178 state = exec->errStateNo;
4179 } else {
4180 state = exec->index;
4181 }
4182 if (terminal != NULL) {
4183 if (comp->compact[state * (comp->nbstrings + 1)] ==
4184 XML_REGEXP_FINAL_STATE)
4185 *terminal = 1;
4186 else
4187 *terminal = 0;
4188 }
4189 for (i = 0;(i < comp->nbstrings) && (nb < maxval);i++) {
4190 target = comp->compact[state * (comp->nbstrings + 1) + i + 1];
4191 if ((target > 0) && (target <= comp->nbstates) &&
4192 (comp->compact[(target - 1) * (comp->nbstrings + 1)] !=
4193 XML_REGEXP_SINK_STATE)) {
4194 values[nb++] = comp->stringMap[i];
4195 (*nbval)++;
4196 }
4197 }
4198 for (i = 0;(i < comp->nbstrings) && (nb < maxval);i++) {
4199 target = comp->compact[state * (comp->nbstrings + 1) + i + 1];
4200 if ((target > 0) && (target <= comp->nbstates) &&
4201 (comp->compact[(target - 1) * (comp->nbstrings + 1)] ==
4202 XML_REGEXP_SINK_STATE)) {
4203 values[nb++] = comp->stringMap[i];
4204 (*nbneg)++;
4205 }
4206 }
4207 } else {
4208 int transno;
4209 xmlRegTransPtr trans;
4210 xmlRegAtomPtr atom;
4211 xmlRegStatePtr state;
4212
4213 if (terminal != NULL) {
4214 if (exec->state->type == XML_REGEXP_FINAL_STATE)
4215 *terminal = 1;
4216 else
4217 *terminal = 0;
4218 }
4219
4220 if (err) {
4221 if (exec->errState == NULL) return(-1);
4222 state = exec->errState;
4223 } else {
4224 if (exec->state == NULL) return(-1);
4225 state = exec->state;
4226 }
4227 for (transno = 0;
4228 (transno < state->nbTrans) && (nb < maxval);
4229 transno++) {
4230 trans = &state->trans[transno];
4231 if (trans->to < 0)
4232 continue;
4233 atom = trans->atom;
4234 if ((atom == NULL) || (atom->valuep == NULL))
4235 continue;
4236 if (trans->count == REGEXP_ALL_LAX_COUNTER) {
4237 /* this should not be reached but ... */
4238 TODO;
4239 } else if (trans->count == REGEXP_ALL_COUNTER) {
4240 /* this should not be reached but ... */
4241 TODO;
4242 } else if (trans->counter >= 0) {
4243 xmlRegCounterPtr counter = NULL;
4244 int count;
4245
4246 if (err)
4247 count = exec->errCounts[trans->counter];
4248 else
4249 count = exec->counts[trans->counter];
4250 if (exec->comp != NULL)
4251 counter = &exec->comp->counters[trans->counter];
4252 if ((counter == NULL) || (count < counter->max)) {
4253 if (atom->neg)
4254 values[nb++] = (xmlChar *) atom->valuep2;
4255 else
4256 values[nb++] = (xmlChar *) atom->valuep;
4257 (*nbval)++;
4258 }
4259 } else {
4260 if ((exec->comp->states[trans->to] != NULL) &&
4261 (exec->comp->states[trans->to]->type !=
4262 XML_REGEXP_SINK_STATE)) {
4263 if (atom->neg)
4264 values[nb++] = (xmlChar *) atom->valuep2;
4265 else
4266 values[nb++] = (xmlChar *) atom->valuep;
4267 (*nbval)++;
4268 }
4269 }
4270 }
4271 for (transno = 0;
4272 (transno < state->nbTrans) && (nb < maxval);
4273 transno++) {
4274 trans = &state->trans[transno];
4275 if (trans->to < 0)
4276 continue;
4277 atom = trans->atom;
4278 if ((atom == NULL) || (atom->valuep == NULL))
4279 continue;
4280 if (trans->count == REGEXP_ALL_LAX_COUNTER) {
4281 continue;
4282 } else if (trans->count == REGEXP_ALL_COUNTER) {
4283 continue;
4284 } else if (trans->counter >= 0) {
4285 continue;
4286 } else {
4287 if ((exec->comp->states[trans->to] != NULL) &&
4288 (exec->comp->states[trans->to]->type ==
4289 XML_REGEXP_SINK_STATE)) {
4290 if (atom->neg)
4291 values[nb++] = (xmlChar *) atom->valuep2;
4292 else
4293 values[nb++] = (xmlChar *) atom->valuep;
4294 (*nbneg)++;
4295 }
4296 }
4297 }
4298 }
4299 return(0);
4300 }
4301
4302 /**
4303 * xmlRegExecNextValues:
4304 * @exec: a regexp execution context
4305 * @nbval: pointer to the number of accepted values IN/OUT
4306 * @nbneg: return number of negative transitions
4307 * @values: pointer to the array of acceptable values
4308 * @terminal: return value if this was a terminal state
4309 *
4310 * Extract informations from the regexp execution,
4311 * the parameter @values must point to an array of @nbval string pointers
4312 * on return nbval will contain the number of possible strings in that
4313 * state and the @values array will be updated with them. The string values
4314 * returned will be freed with the @exec context and don't need to be
4315 * deallocated.
4316 *
4317 * Returns: 0 in case of success or -1 in case of error.
4318 */
4319 int
xmlRegExecNextValues(xmlRegExecCtxtPtr exec,int * nbval,int * nbneg,xmlChar ** values,int * terminal)4320 xmlRegExecNextValues(xmlRegExecCtxtPtr exec, int *nbval, int *nbneg,
4321 xmlChar **values, int *terminal) {
4322 return(xmlRegExecGetValues(exec, 0, nbval, nbneg, values, terminal));
4323 }
4324
4325 /**
4326 * xmlRegExecErrInfo:
4327 * @exec: a regexp execution context generating an error
4328 * @string: return value for the error string
4329 * @nbval: pointer to the number of accepted values IN/OUT
4330 * @nbneg: return number of negative transitions
4331 * @values: pointer to the array of acceptable values
4332 * @terminal: return value if this was a terminal state
4333 *
4334 * Extract error informations from the regexp execution, the parameter
4335 * @string will be updated with the value pushed and not accepted,
4336 * the parameter @values must point to an array of @nbval string pointers
4337 * on return nbval will contain the number of possible strings in that
4338 * state and the @values array will be updated with them. The string values
4339 * returned will be freed with the @exec context and don't need to be
4340 * deallocated.
4341 *
4342 * Returns: 0 in case of success or -1 in case of error.
4343 */
4344 int
xmlRegExecErrInfo(xmlRegExecCtxtPtr exec,const xmlChar ** string,int * nbval,int * nbneg,xmlChar ** values,int * terminal)4345 xmlRegExecErrInfo(xmlRegExecCtxtPtr exec, const xmlChar **string,
4346 int *nbval, int *nbneg, xmlChar **values, int *terminal) {
4347 if (exec == NULL)
4348 return(-1);
4349 if (string != NULL) {
4350 if (exec->status != 0)
4351 *string = exec->errString;
4352 else
4353 *string = NULL;
4354 }
4355 return(xmlRegExecGetValues(exec, 1, nbval, nbneg, values, terminal));
4356 }
4357
4358 #ifdef DEBUG_ERR
testerr(xmlRegExecCtxtPtr exec)4359 static void testerr(xmlRegExecCtxtPtr exec) {
4360 const xmlChar *string;
4361 xmlChar *values[5];
4362 int nb = 5;
4363 int nbneg;
4364 int terminal;
4365 xmlRegExecErrInfo(exec, &string, &nb, &nbneg, &values[0], &terminal);
4366 }
4367 #endif
4368
4369 #if 0
4370 static int
4371 xmlRegExecPushChar(xmlRegExecCtxtPtr exec, int UCS) {
4372 xmlRegTransPtr trans;
4373 xmlRegAtomPtr atom;
4374 int ret;
4375 int codepoint, len;
4376
4377 if (exec == NULL)
4378 return(-1);
4379 if (exec->status != 0)
4380 return(exec->status);
4381
4382 while ((exec->status == 0) &&
4383 ((exec->inputString[exec->index] != 0) ||
4384 (exec->state->type != XML_REGEXP_FINAL_STATE))) {
4385
4386 /*
4387 * End of input on non-terminal state, rollback, however we may
4388 * still have epsilon like transition for counted transitions
4389 * on counters, in that case don't break too early.
4390 */
4391 if ((exec->inputString[exec->index] == 0) && (exec->counts == NULL))
4392 goto rollback;
4393
4394 exec->transcount = 0;
4395 for (;exec->transno < exec->state->nbTrans;exec->transno++) {
4396 trans = &exec->state->trans[exec->transno];
4397 if (trans->to < 0)
4398 continue;
4399 atom = trans->atom;
4400 ret = 0;
4401 if (trans->count >= 0) {
4402 int count;
4403 xmlRegCounterPtr counter;
4404
4405 /*
4406 * A counted transition.
4407 */
4408
4409 count = exec->counts[trans->count];
4410 counter = &exec->comp->counters[trans->count];
4411 #ifdef DEBUG_REGEXP_EXEC
4412 printf("testing count %d: val %d, min %d, max %d\n",
4413 trans->count, count, counter->min, counter->max);
4414 #endif
4415 ret = ((count >= counter->min) && (count <= counter->max));
4416 } else if (atom == NULL) {
4417 fprintf(stderr, "epsilon transition left at runtime\n");
4418 exec->status = -2;
4419 break;
4420 } else if (exec->inputString[exec->index] != 0) {
4421 codepoint = CUR_SCHAR(&(exec->inputString[exec->index]), len);
4422 ret = xmlRegCheckCharacter(atom, codepoint);
4423 if ((ret == 1) && (atom->min > 0) && (atom->max > 0)) {
4424 xmlRegStatePtr to = exec->comp->states[trans->to];
4425
4426 /*
4427 * this is a multiple input sequence
4428 */
4429 if (exec->state->nbTrans > exec->transno + 1) {
4430 xmlFARegExecSave(exec);
4431 }
4432 exec->transcount = 1;
4433 do {
4434 /*
4435 * Try to progress as much as possible on the input
4436 */
4437 if (exec->transcount == atom->max) {
4438 break;
4439 }
4440 exec->index += len;
4441 /*
4442 * End of input: stop here
4443 */
4444 if (exec->inputString[exec->index] == 0) {
4445 exec->index -= len;
4446 break;
4447 }
4448 if (exec->transcount >= atom->min) {
4449 int transno = exec->transno;
4450 xmlRegStatePtr state = exec->state;
4451
4452 /*
4453 * The transition is acceptable save it
4454 */
4455 exec->transno = -1; /* trick */
4456 exec->state = to;
4457 xmlFARegExecSave(exec);
4458 exec->transno = transno;
4459 exec->state = state;
4460 }
4461 codepoint = CUR_SCHAR(&(exec->inputString[exec->index]),
4462 len);
4463 ret = xmlRegCheckCharacter(atom, codepoint);
4464 exec->transcount++;
4465 } while (ret == 1);
4466 if (exec->transcount < atom->min)
4467 ret = 0;
4468
4469 /*
4470 * If the last check failed but one transition was found
4471 * possible, rollback
4472 */
4473 if (ret < 0)
4474 ret = 0;
4475 if (ret == 0) {
4476 goto rollback;
4477 }
4478 }
4479 }
4480 if (ret == 1) {
4481 if (exec->state->nbTrans > exec->transno + 1) {
4482 xmlFARegExecSave(exec);
4483 }
4484 /*
4485 * restart count for expressions like this ((abc){2})*
4486 */
4487 if (trans->count >= 0) {
4488 #ifdef DEBUG_REGEXP_EXEC
4489 printf("Reset count %d\n", trans->count);
4490 #endif
4491 exec->counts[trans->count] = 0;
4492 }
4493 if (trans->counter >= 0) {
4494 #ifdef DEBUG_REGEXP_EXEC
4495 printf("Increasing count %d\n", trans->counter);
4496 #endif
4497 exec->counts[trans->counter]++;
4498 }
4499 #ifdef DEBUG_REGEXP_EXEC
4500 printf("entering state %d\n", trans->to);
4501 #endif
4502 exec->state = exec->comp->states[trans->to];
4503 exec->transno = 0;
4504 if (trans->atom != NULL) {
4505 exec->index += len;
4506 }
4507 goto progress;
4508 } else if (ret < 0) {
4509 exec->status = -4;
4510 break;
4511 }
4512 }
4513 if ((exec->transno != 0) || (exec->state->nbTrans == 0)) {
4514 rollback:
4515 /*
4516 * Failed to find a way out
4517 */
4518 exec->determinist = 0;
4519 xmlFARegExecRollBack(exec);
4520 }
4521 progress:
4522 continue;
4523 }
4524 }
4525 #endif
4526 /************************************************************************
4527 * *
4528 * Parser for the Schemas Datatype Regular Expressions *
4529 * http://www.w3.org/TR/2001/REC-xmlschema-2-20010502/#regexs *
4530 * *
4531 ************************************************************************/
4532
4533 /**
4534 * xmlFAIsChar:
4535 * @ctxt: a regexp parser context
4536 *
4537 * [10] Char ::= [^.\?*+()|#x5B#x5D]
4538 */
4539 static int
xmlFAIsChar(xmlRegParserCtxtPtr ctxt)4540 xmlFAIsChar(xmlRegParserCtxtPtr ctxt) {
4541 int cur;
4542 int len;
4543
4544 cur = CUR_SCHAR(ctxt->cur, len);
4545 if ((cur == '.') || (cur == '\\') || (cur == '?') ||
4546 (cur == '*') || (cur == '+') || (cur == '(') ||
4547 (cur == ')') || (cur == '|') || (cur == 0x5B) ||
4548 (cur == 0x5D) || (cur == 0))
4549 return(-1);
4550 return(cur);
4551 }
4552
4553 /**
4554 * xmlFAParseCharProp:
4555 * @ctxt: a regexp parser context
4556 *
4557 * [27] charProp ::= IsCategory | IsBlock
4558 * [28] IsCategory ::= Letters | Marks | Numbers | Punctuation |
4559 * Separators | Symbols | Others
4560 * [29] Letters ::= 'L' [ultmo]?
4561 * [30] Marks ::= 'M' [nce]?
4562 * [31] Numbers ::= 'N' [dlo]?
4563 * [32] Punctuation ::= 'P' [cdseifo]?
4564 * [33] Separators ::= 'Z' [slp]?
4565 * [34] Symbols ::= 'S' [mcko]?
4566 * [35] Others ::= 'C' [cfon]?
4567 * [36] IsBlock ::= 'Is' [a-zA-Z0-9#x2D]+
4568 */
4569 static void
xmlFAParseCharProp(xmlRegParserCtxtPtr ctxt)4570 xmlFAParseCharProp(xmlRegParserCtxtPtr ctxt) {
4571 int cur;
4572 xmlRegAtomType type = (xmlRegAtomType) 0;
4573 xmlChar *blockName = NULL;
4574
4575 cur = CUR;
4576 if (cur == 'L') {
4577 NEXT;
4578 cur = CUR;
4579 if (cur == 'u') {
4580 NEXT;
4581 type = XML_REGEXP_LETTER_UPPERCASE;
4582 } else if (cur == 'l') {
4583 NEXT;
4584 type = XML_REGEXP_LETTER_LOWERCASE;
4585 } else if (cur == 't') {
4586 NEXT;
4587 type = XML_REGEXP_LETTER_TITLECASE;
4588 } else if (cur == 'm') {
4589 NEXT;
4590 type = XML_REGEXP_LETTER_MODIFIER;
4591 } else if (cur == 'o') {
4592 NEXT;
4593 type = XML_REGEXP_LETTER_OTHERS;
4594 } else {
4595 type = XML_REGEXP_LETTER;
4596 }
4597 } else if (cur == 'M') {
4598 NEXT;
4599 cur = CUR;
4600 if (cur == 'n') {
4601 NEXT;
4602 /* nonspacing */
4603 type = XML_REGEXP_MARK_NONSPACING;
4604 } else if (cur == 'c') {
4605 NEXT;
4606 /* spacing combining */
4607 type = XML_REGEXP_MARK_SPACECOMBINING;
4608 } else if (cur == 'e') {
4609 NEXT;
4610 /* enclosing */
4611 type = XML_REGEXP_MARK_ENCLOSING;
4612 } else {
4613 /* all marks */
4614 type = XML_REGEXP_MARK;
4615 }
4616 } else if (cur == 'N') {
4617 NEXT;
4618 cur = CUR;
4619 if (cur == 'd') {
4620 NEXT;
4621 /* digital */
4622 type = XML_REGEXP_NUMBER_DECIMAL;
4623 } else if (cur == 'l') {
4624 NEXT;
4625 /* letter */
4626 type = XML_REGEXP_NUMBER_LETTER;
4627 } else if (cur == 'o') {
4628 NEXT;
4629 /* other */
4630 type = XML_REGEXP_NUMBER_OTHERS;
4631 } else {
4632 /* all numbers */
4633 type = XML_REGEXP_NUMBER;
4634 }
4635 } else if (cur == 'P') {
4636 NEXT;
4637 cur = CUR;
4638 if (cur == 'c') {
4639 NEXT;
4640 /* connector */
4641 type = XML_REGEXP_PUNCT_CONNECTOR;
4642 } else if (cur == 'd') {
4643 NEXT;
4644 /* dash */
4645 type = XML_REGEXP_PUNCT_DASH;
4646 } else if (cur == 's') {
4647 NEXT;
4648 /* open */
4649 type = XML_REGEXP_PUNCT_OPEN;
4650 } else if (cur == 'e') {
4651 NEXT;
4652 /* close */
4653 type = XML_REGEXP_PUNCT_CLOSE;
4654 } else if (cur == 'i') {
4655 NEXT;
4656 /* initial quote */
4657 type = XML_REGEXP_PUNCT_INITQUOTE;
4658 } else if (cur == 'f') {
4659 NEXT;
4660 /* final quote */
4661 type = XML_REGEXP_PUNCT_FINQUOTE;
4662 } else if (cur == 'o') {
4663 NEXT;
4664 /* other */
4665 type = XML_REGEXP_PUNCT_OTHERS;
4666 } else {
4667 /* all punctuation */
4668 type = XML_REGEXP_PUNCT;
4669 }
4670 } else if (cur == 'Z') {
4671 NEXT;
4672 cur = CUR;
4673 if (cur == 's') {
4674 NEXT;
4675 /* space */
4676 type = XML_REGEXP_SEPAR_SPACE;
4677 } else if (cur == 'l') {
4678 NEXT;
4679 /* line */
4680 type = XML_REGEXP_SEPAR_LINE;
4681 } else if (cur == 'p') {
4682 NEXT;
4683 /* paragraph */
4684 type = XML_REGEXP_SEPAR_PARA;
4685 } else {
4686 /* all separators */
4687 type = XML_REGEXP_SEPAR;
4688 }
4689 } else if (cur == 'S') {
4690 NEXT;
4691 cur = CUR;
4692 if (cur == 'm') {
4693 NEXT;
4694 type = XML_REGEXP_SYMBOL_MATH;
4695 /* math */
4696 } else if (cur == 'c') {
4697 NEXT;
4698 type = XML_REGEXP_SYMBOL_CURRENCY;
4699 /* currency */
4700 } else if (cur == 'k') {
4701 NEXT;
4702 type = XML_REGEXP_SYMBOL_MODIFIER;
4703 /* modifiers */
4704 } else if (cur == 'o') {
4705 NEXT;
4706 type = XML_REGEXP_SYMBOL_OTHERS;
4707 /* other */
4708 } else {
4709 /* all symbols */
4710 type = XML_REGEXP_SYMBOL;
4711 }
4712 } else if (cur == 'C') {
4713 NEXT;
4714 cur = CUR;
4715 if (cur == 'c') {
4716 NEXT;
4717 /* control */
4718 type = XML_REGEXP_OTHER_CONTROL;
4719 } else if (cur == 'f') {
4720 NEXT;
4721 /* format */
4722 type = XML_REGEXP_OTHER_FORMAT;
4723 } else if (cur == 'o') {
4724 NEXT;
4725 /* private use */
4726 type = XML_REGEXP_OTHER_PRIVATE;
4727 } else if (cur == 'n') {
4728 NEXT;
4729 /* not assigned */
4730 type = XML_REGEXP_OTHER_NA;
4731 } else {
4732 /* all others */
4733 type = XML_REGEXP_OTHER;
4734 }
4735 } else if (cur == 'I') {
4736 const xmlChar *start;
4737 NEXT;
4738 cur = CUR;
4739 if (cur != 's') {
4740 ERROR("IsXXXX expected");
4741 return;
4742 }
4743 NEXT;
4744 start = ctxt->cur;
4745 cur = CUR;
4746 if (((cur >= 'a') && (cur <= 'z')) ||
4747 ((cur >= 'A') && (cur <= 'Z')) ||
4748 ((cur >= '0') && (cur <= '9')) ||
4749 (cur == 0x2D)) {
4750 NEXT;
4751 cur = CUR;
4752 while (((cur >= 'a') && (cur <= 'z')) ||
4753 ((cur >= 'A') && (cur <= 'Z')) ||
4754 ((cur >= '0') && (cur <= '9')) ||
4755 (cur == 0x2D)) {
4756 NEXT;
4757 cur = CUR;
4758 }
4759 }
4760 type = XML_REGEXP_BLOCK_NAME;
4761 blockName = xmlStrndup(start, ctxt->cur - start);
4762 } else {
4763 ERROR("Unknown char property");
4764 return;
4765 }
4766 if (ctxt->atom == NULL) {
4767 ctxt->atom = xmlRegNewAtom(ctxt, type);
4768 if (ctxt->atom != NULL)
4769 ctxt->atom->valuep = blockName;
4770 } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
4771 xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
4772 type, 0, 0, blockName);
4773 }
4774 }
4775
4776 /**
4777 * xmlFAParseCharClassEsc:
4778 * @ctxt: a regexp parser context
4779 *
4780 * [23] charClassEsc ::= ( SingleCharEsc | MultiCharEsc | catEsc | complEsc )
4781 * [24] SingleCharEsc ::= '\' [nrt\|.?*+(){}#x2D#x5B#x5D#x5E]
4782 * [25] catEsc ::= '\p{' charProp '}'
4783 * [26] complEsc ::= '\P{' charProp '}'
4784 * [37] MultiCharEsc ::= '.' | ('\' [sSiIcCdDwW])
4785 */
4786 static void
xmlFAParseCharClassEsc(xmlRegParserCtxtPtr ctxt)4787 xmlFAParseCharClassEsc(xmlRegParserCtxtPtr ctxt) {
4788 int cur;
4789
4790 if (CUR == '.') {
4791 if (ctxt->atom == NULL) {
4792 ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_ANYCHAR);
4793 } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
4794 xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
4795 XML_REGEXP_ANYCHAR, 0, 0, NULL);
4796 }
4797 NEXT;
4798 return;
4799 }
4800 if (CUR != '\\') {
4801 ERROR("Escaped sequence: expecting \\");
4802 return;
4803 }
4804 NEXT;
4805 cur = CUR;
4806 if (cur == 'p') {
4807 NEXT;
4808 if (CUR != '{') {
4809 ERROR("Expecting '{'");
4810 return;
4811 }
4812 NEXT;
4813 xmlFAParseCharProp(ctxt);
4814 if (CUR != '}') {
4815 ERROR("Expecting '}'");
4816 return;
4817 }
4818 NEXT;
4819 } else if (cur == 'P') {
4820 NEXT;
4821 if (CUR != '{') {
4822 ERROR("Expecting '{'");
4823 return;
4824 }
4825 NEXT;
4826 xmlFAParseCharProp(ctxt);
4827 ctxt->atom->neg = 1;
4828 if (CUR != '}') {
4829 ERROR("Expecting '}'");
4830 return;
4831 }
4832 NEXT;
4833 } else if ((cur == 'n') || (cur == 'r') || (cur == 't') || (cur == '\\') ||
4834 (cur == '|') || (cur == '.') || (cur == '?') || (cur == '*') ||
4835 (cur == '+') || (cur == '(') || (cur == ')') || (cur == '{') ||
4836 (cur == '}') || (cur == 0x2D) || (cur == 0x5B) || (cur == 0x5D) ||
4837 (cur == 0x5E)) {
4838 if (ctxt->atom == NULL) {
4839 ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_CHARVAL);
4840 if (ctxt->atom != NULL) {
4841 switch (cur) {
4842 case 'n':
4843 ctxt->atom->codepoint = '\n';
4844 break;
4845 case 'r':
4846 ctxt->atom->codepoint = '\r';
4847 break;
4848 case 't':
4849 ctxt->atom->codepoint = '\t';
4850 break;
4851 default:
4852 ctxt->atom->codepoint = cur;
4853 }
4854 }
4855 } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
4856 xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
4857 XML_REGEXP_CHARVAL, cur, cur, NULL);
4858 }
4859 NEXT;
4860 } else if ((cur == 's') || (cur == 'S') || (cur == 'i') || (cur == 'I') ||
4861 (cur == 'c') || (cur == 'C') || (cur == 'd') || (cur == 'D') ||
4862 (cur == 'w') || (cur == 'W')) {
4863 xmlRegAtomType type = XML_REGEXP_ANYSPACE;
4864
4865 switch (cur) {
4866 case 's':
4867 type = XML_REGEXP_ANYSPACE;
4868 break;
4869 case 'S':
4870 type = XML_REGEXP_NOTSPACE;
4871 break;
4872 case 'i':
4873 type = XML_REGEXP_INITNAME;
4874 break;
4875 case 'I':
4876 type = XML_REGEXP_NOTINITNAME;
4877 break;
4878 case 'c':
4879 type = XML_REGEXP_NAMECHAR;
4880 break;
4881 case 'C':
4882 type = XML_REGEXP_NOTNAMECHAR;
4883 break;
4884 case 'd':
4885 type = XML_REGEXP_DECIMAL;
4886 break;
4887 case 'D':
4888 type = XML_REGEXP_NOTDECIMAL;
4889 break;
4890 case 'w':
4891 type = XML_REGEXP_REALCHAR;
4892 break;
4893 case 'W':
4894 type = XML_REGEXP_NOTREALCHAR;
4895 break;
4896 }
4897 NEXT;
4898 if (ctxt->atom == NULL) {
4899 ctxt->atom = xmlRegNewAtom(ctxt, type);
4900 } else if (ctxt->atom->type == XML_REGEXP_RANGES) {
4901 xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
4902 type, 0, 0, NULL);
4903 }
4904 } else {
4905 ERROR("Wrong escape sequence, misuse of character '\\'");
4906 }
4907 }
4908
4909 /**
4910 * xmlFAParseCharRange:
4911 * @ctxt: a regexp parser context
4912 *
4913 * [17] charRange ::= seRange | XmlCharRef | XmlCharIncDash
4914 * [18] seRange ::= charOrEsc '-' charOrEsc
4915 * [20] charOrEsc ::= XmlChar | SingleCharEsc
4916 * [21] XmlChar ::= [^\#x2D#x5B#x5D]
4917 * [22] XmlCharIncDash ::= [^\#x5B#x5D]
4918 */
4919 static void
xmlFAParseCharRange(xmlRegParserCtxtPtr ctxt)4920 xmlFAParseCharRange(xmlRegParserCtxtPtr ctxt) {
4921 int cur, len;
4922 int start = -1;
4923 int end = -1;
4924
4925 if (CUR == '\0') {
4926 ERROR("Expecting ']'");
4927 return;
4928 }
4929
4930 cur = CUR;
4931 if (cur == '\\') {
4932 NEXT;
4933 cur = CUR;
4934 switch (cur) {
4935 case 'n': start = 0xA; break;
4936 case 'r': start = 0xD; break;
4937 case 't': start = 0x9; break;
4938 case '\\': case '|': case '.': case '-': case '^': case '?':
4939 case '*': case '+': case '{': case '}': case '(': case ')':
4940 case '[': case ']':
4941 start = cur; break;
4942 default:
4943 ERROR("Invalid escape value");
4944 return;
4945 }
4946 end = start;
4947 len = 1;
4948 } else if ((cur != 0x5B) && (cur != 0x5D)) {
4949 end = start = CUR_SCHAR(ctxt->cur, len);
4950 } else {
4951 ERROR("Expecting a char range");
4952 return;
4953 }
4954 /*
4955 * Since we are "inside" a range, we can assume ctxt->cur is past
4956 * the start of ctxt->string, and PREV should be safe
4957 */
4958 if ((start == '-') && (NXT(1) != ']') && (PREV != '[') && (PREV != '^')) {
4959 NEXTL(len);
4960 return;
4961 }
4962 NEXTL(len);
4963 cur = CUR;
4964 if ((cur != '-') || (NXT(1) == ']')) {
4965 xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
4966 XML_REGEXP_CHARVAL, start, end, NULL);
4967 return;
4968 }
4969 NEXT;
4970 cur = CUR;
4971 if (cur == '\\') {
4972 NEXT;
4973 cur = CUR;
4974 switch (cur) {
4975 case 'n': end = 0xA; break;
4976 case 'r': end = 0xD; break;
4977 case 't': end = 0x9; break;
4978 case '\\': case '|': case '.': case '-': case '^': case '?':
4979 case '*': case '+': case '{': case '}': case '(': case ')':
4980 case '[': case ']':
4981 end = cur; break;
4982 default:
4983 ERROR("Invalid escape value");
4984 return;
4985 }
4986 len = 1;
4987 } else if ((cur != 0x5B) && (cur != 0x5D)) {
4988 end = CUR_SCHAR(ctxt->cur, len);
4989 } else {
4990 ERROR("Expecting the end of a char range");
4991 return;
4992 }
4993 NEXTL(len);
4994 /* TODO check that the values are acceptable character ranges for XML */
4995 if (end < start) {
4996 ERROR("End of range is before start of range");
4997 } else {
4998 xmlRegAtomAddRange(ctxt, ctxt->atom, ctxt->neg,
4999 XML_REGEXP_CHARVAL, start, end, NULL);
5000 }
5001 return;
5002 }
5003
5004 /**
5005 * xmlFAParsePosCharGroup:
5006 * @ctxt: a regexp parser context
5007 *
5008 * [14] posCharGroup ::= ( charRange | charClassEsc )+
5009 */
5010 static void
xmlFAParsePosCharGroup(xmlRegParserCtxtPtr ctxt)5011 xmlFAParsePosCharGroup(xmlRegParserCtxtPtr ctxt) {
5012 do {
5013 if (CUR == '\\') {
5014 xmlFAParseCharClassEsc(ctxt);
5015 } else {
5016 xmlFAParseCharRange(ctxt);
5017 }
5018 } while ((CUR != ']') && (CUR != '^') && (CUR != '-') &&
5019 (CUR != 0) && (ctxt->error == 0));
5020 }
5021
5022 /**
5023 * xmlFAParseCharGroup:
5024 * @ctxt: a regexp parser context
5025 *
5026 * [13] charGroup ::= posCharGroup | negCharGroup | charClassSub
5027 * [15] negCharGroup ::= '^' posCharGroup
5028 * [16] charClassSub ::= ( posCharGroup | negCharGroup ) '-' charClassExpr
5029 * [12] charClassExpr ::= '[' charGroup ']'
5030 */
5031 static void
xmlFAParseCharGroup(xmlRegParserCtxtPtr ctxt)5032 xmlFAParseCharGroup(xmlRegParserCtxtPtr ctxt) {
5033 int n = ctxt->neg;
5034 while ((CUR != ']') && (ctxt->error == 0)) {
5035 if (CUR == '^') {
5036 int neg = ctxt->neg;
5037
5038 NEXT;
5039 ctxt->neg = !ctxt->neg;
5040 xmlFAParsePosCharGroup(ctxt);
5041 ctxt->neg = neg;
5042 } else if ((CUR == '-') && (NXT(1) == '[')) {
5043 int neg = ctxt->neg;
5044 ctxt->neg = 2;
5045 NEXT; /* eat the '-' */
5046 NEXT; /* eat the '[' */
5047 xmlFAParseCharGroup(ctxt);
5048 if (CUR == ']') {
5049 NEXT;
5050 } else {
5051 ERROR("charClassExpr: ']' expected");
5052 break;
5053 }
5054 ctxt->neg = neg;
5055 break;
5056 } else if (CUR != ']') {
5057 xmlFAParsePosCharGroup(ctxt);
5058 }
5059 }
5060 ctxt->neg = n;
5061 }
5062
5063 /**
5064 * xmlFAParseCharClass:
5065 * @ctxt: a regexp parser context
5066 *
5067 * [11] charClass ::= charClassEsc | charClassExpr
5068 * [12] charClassExpr ::= '[' charGroup ']'
5069 */
5070 static void
xmlFAParseCharClass(xmlRegParserCtxtPtr ctxt)5071 xmlFAParseCharClass(xmlRegParserCtxtPtr ctxt) {
5072 if (CUR == '[') {
5073 NEXT;
5074 ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_RANGES);
5075 if (ctxt->atom == NULL)
5076 return;
5077 xmlFAParseCharGroup(ctxt);
5078 if (CUR == ']') {
5079 NEXT;
5080 } else {
5081 ERROR("xmlFAParseCharClass: ']' expected");
5082 }
5083 } else {
5084 xmlFAParseCharClassEsc(ctxt);
5085 }
5086 }
5087
5088 /**
5089 * xmlFAParseQuantExact:
5090 * @ctxt: a regexp parser context
5091 *
5092 * [8] QuantExact ::= [0-9]+
5093 *
5094 * Returns 0 if success or -1 in case of error
5095 */
5096 static int
xmlFAParseQuantExact(xmlRegParserCtxtPtr ctxt)5097 xmlFAParseQuantExact(xmlRegParserCtxtPtr ctxt) {
5098 int ret = 0;
5099 int ok = 0;
5100
5101 while ((CUR >= '0') && (CUR <= '9')) {
5102 ret = ret * 10 + (CUR - '0');
5103 ok = 1;
5104 NEXT;
5105 }
5106 if (ok != 1) {
5107 return(-1);
5108 }
5109 return(ret);
5110 }
5111
5112 /**
5113 * xmlFAParseQuantifier:
5114 * @ctxt: a regexp parser context
5115 *
5116 * [4] quantifier ::= [?*+] | ( '{' quantity '}' )
5117 * [5] quantity ::= quantRange | quantMin | QuantExact
5118 * [6] quantRange ::= QuantExact ',' QuantExact
5119 * [7] quantMin ::= QuantExact ','
5120 * [8] QuantExact ::= [0-9]+
5121 */
5122 static int
xmlFAParseQuantifier(xmlRegParserCtxtPtr ctxt)5123 xmlFAParseQuantifier(xmlRegParserCtxtPtr ctxt) {
5124 int cur;
5125
5126 cur = CUR;
5127 if ((cur == '?') || (cur == '*') || (cur == '+')) {
5128 if (ctxt->atom != NULL) {
5129 if (cur == '?')
5130 ctxt->atom->quant = XML_REGEXP_QUANT_OPT;
5131 else if (cur == '*')
5132 ctxt->atom->quant = XML_REGEXP_QUANT_MULT;
5133 else if (cur == '+')
5134 ctxt->atom->quant = XML_REGEXP_QUANT_PLUS;
5135 }
5136 NEXT;
5137 return(1);
5138 }
5139 if (cur == '{') {
5140 int min = 0, max = 0;
5141
5142 NEXT;
5143 cur = xmlFAParseQuantExact(ctxt);
5144 if (cur >= 0)
5145 min = cur;
5146 if (CUR == ',') {
5147 NEXT;
5148 if (CUR == '}')
5149 max = INT_MAX;
5150 else {
5151 cur = xmlFAParseQuantExact(ctxt);
5152 if (cur >= 0)
5153 max = cur;
5154 else {
5155 ERROR("Improper quantifier");
5156 }
5157 }
5158 }
5159 if (CUR == '}') {
5160 NEXT;
5161 } else {
5162 ERROR("Unterminated quantifier");
5163 }
5164 if (max == 0)
5165 max = min;
5166 if (ctxt->atom != NULL) {
5167 ctxt->atom->quant = XML_REGEXP_QUANT_RANGE;
5168 ctxt->atom->min = min;
5169 ctxt->atom->max = max;
5170 }
5171 return(1);
5172 }
5173 return(0);
5174 }
5175
5176 /**
5177 * xmlFAParseAtom:
5178 * @ctxt: a regexp parser context
5179 *
5180 * [9] atom ::= Char | charClass | ( '(' regExp ')' )
5181 */
5182 static int
xmlFAParseAtom(xmlRegParserCtxtPtr ctxt)5183 xmlFAParseAtom(xmlRegParserCtxtPtr ctxt) {
5184 int codepoint, len;
5185
5186 codepoint = xmlFAIsChar(ctxt);
5187 if (codepoint > 0) {
5188 ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_CHARVAL);
5189 if (ctxt->atom == NULL)
5190 return(-1);
5191 codepoint = CUR_SCHAR(ctxt->cur, len);
5192 ctxt->atom->codepoint = codepoint;
5193 NEXTL(len);
5194 return(1);
5195 } else if (CUR == '|') {
5196 return(0);
5197 } else if (CUR == 0) {
5198 return(0);
5199 } else if (CUR == ')') {
5200 return(0);
5201 } else if (CUR == '(') {
5202 xmlRegStatePtr start, oldend, start0;
5203
5204 NEXT;
5205 /*
5206 * this extra Epsilon transition is needed if we count with 0 allowed
5207 * unfortunately this can't be known at that point
5208 */
5209 xmlFAGenerateEpsilonTransition(ctxt, ctxt->state, NULL);
5210 start0 = ctxt->state;
5211 xmlFAGenerateEpsilonTransition(ctxt, ctxt->state, NULL);
5212 start = ctxt->state;
5213 oldend = ctxt->end;
5214 ctxt->end = NULL;
5215 ctxt->atom = NULL;
5216 xmlFAParseRegExp(ctxt, 0);
5217 if (CUR == ')') {
5218 NEXT;
5219 } else {
5220 ERROR("xmlFAParseAtom: expecting ')'");
5221 }
5222 ctxt->atom = xmlRegNewAtom(ctxt, XML_REGEXP_SUBREG);
5223 if (ctxt->atom == NULL)
5224 return(-1);
5225 ctxt->atom->start = start;
5226 ctxt->atom->start0 = start0;
5227 ctxt->atom->stop = ctxt->state;
5228 ctxt->end = oldend;
5229 return(1);
5230 } else if ((CUR == '[') || (CUR == '\\') || (CUR == '.')) {
5231 xmlFAParseCharClass(ctxt);
5232 return(1);
5233 }
5234 return(0);
5235 }
5236
5237 /**
5238 * xmlFAParsePiece:
5239 * @ctxt: a regexp parser context
5240 *
5241 * [3] piece ::= atom quantifier?
5242 */
5243 static int
xmlFAParsePiece(xmlRegParserCtxtPtr ctxt)5244 xmlFAParsePiece(xmlRegParserCtxtPtr ctxt) {
5245 int ret;
5246
5247 ctxt->atom = NULL;
5248 ret = xmlFAParseAtom(ctxt);
5249 if (ret == 0)
5250 return(0);
5251 if (ctxt->atom == NULL) {
5252 ERROR("internal: no atom generated");
5253 }
5254 xmlFAParseQuantifier(ctxt);
5255 return(1);
5256 }
5257
5258 /**
5259 * xmlFAParseBranch:
5260 * @ctxt: a regexp parser context
5261 * @to: optional target to the end of the branch
5262 *
5263 * @to is used to optimize by removing duplicate path in automata
5264 * in expressions like (a|b)(c|d)
5265 *
5266 * [2] branch ::= piece*
5267 */
5268 static int
xmlFAParseBranch(xmlRegParserCtxtPtr ctxt,xmlRegStatePtr to)5269 xmlFAParseBranch(xmlRegParserCtxtPtr ctxt, xmlRegStatePtr to) {
5270 xmlRegStatePtr previous;
5271 int ret;
5272
5273 previous = ctxt->state;
5274 ret = xmlFAParsePiece(ctxt);
5275 if (ret != 0) {
5276 if (xmlFAGenerateTransitions(ctxt, previous,
5277 (CUR=='|' || CUR==')') ? to : NULL, ctxt->atom) < 0)
5278 return(-1);
5279 previous = ctxt->state;
5280 ctxt->atom = NULL;
5281 }
5282 while ((ret != 0) && (ctxt->error == 0)) {
5283 ret = xmlFAParsePiece(ctxt);
5284 if (ret != 0) {
5285 if (xmlFAGenerateTransitions(ctxt, previous,
5286 (CUR=='|' || CUR==')') ? to : NULL, ctxt->atom) < 0)
5287 return(-1);
5288 previous = ctxt->state;
5289 ctxt->atom = NULL;
5290 }
5291 }
5292 return(0);
5293 }
5294
5295 /**
5296 * xmlFAParseRegExp:
5297 * @ctxt: a regexp parser context
5298 * @top: is this the top-level expression ?
5299 *
5300 * [1] regExp ::= branch ( '|' branch )*
5301 */
5302 static void
xmlFAParseRegExp(xmlRegParserCtxtPtr ctxt,int top)5303 xmlFAParseRegExp(xmlRegParserCtxtPtr ctxt, int top) {
5304 xmlRegStatePtr start, end;
5305
5306 /* if not top start should have been generated by an epsilon trans */
5307 start = ctxt->state;
5308 ctxt->end = NULL;
5309 xmlFAParseBranch(ctxt, NULL);
5310 if (top) {
5311 #ifdef DEBUG_REGEXP_GRAPH
5312 printf("State %d is final\n", ctxt->state->no);
5313 #endif
5314 ctxt->state->type = XML_REGEXP_FINAL_STATE;
5315 }
5316 if (CUR != '|') {
5317 ctxt->end = ctxt->state;
5318 return;
5319 }
5320 end = ctxt->state;
5321 while ((CUR == '|') && (ctxt->error == 0)) {
5322 NEXT;
5323 ctxt->state = start;
5324 ctxt->end = NULL;
5325 xmlFAParseBranch(ctxt, end);
5326 }
5327 if (!top) {
5328 ctxt->state = end;
5329 ctxt->end = end;
5330 }
5331 }
5332
5333 /************************************************************************
5334 * *
5335 * The basic API *
5336 * *
5337 ************************************************************************/
5338
5339 /**
5340 * xmlRegexpPrint:
5341 * @output: the file for the output debug
5342 * @regexp: the compiled regexp
5343 *
5344 * Print the content of the compiled regular expression
5345 */
5346 void
xmlRegexpPrint(FILE * output,xmlRegexpPtr regexp)5347 xmlRegexpPrint(FILE *output, xmlRegexpPtr regexp) {
5348 int i;
5349
5350 if (output == NULL)
5351 return;
5352 fprintf(output, " regexp: ");
5353 if (regexp == NULL) {
5354 fprintf(output, "NULL\n");
5355 return;
5356 }
5357 fprintf(output, "'%s' ", regexp->string);
5358 fprintf(output, "\n");
5359 fprintf(output, "%d atoms:\n", regexp->nbAtoms);
5360 for (i = 0;i < regexp->nbAtoms; i++) {
5361 fprintf(output, " %02d ", i);
5362 xmlRegPrintAtom(output, regexp->atoms[i]);
5363 }
5364 fprintf(output, "%d states:", regexp->nbStates);
5365 fprintf(output, "\n");
5366 for (i = 0;i < regexp->nbStates; i++) {
5367 xmlRegPrintState(output, regexp->states[i]);
5368 }
5369 fprintf(output, "%d counters:\n", regexp->nbCounters);
5370 for (i = 0;i < regexp->nbCounters; i++) {
5371 fprintf(output, " %d: min %d max %d\n", i, regexp->counters[i].min,
5372 regexp->counters[i].max);
5373 }
5374 }
5375
5376 /**
5377 * xmlRegexpCompile:
5378 * @regexp: a regular expression string
5379 *
5380 * Parses a regular expression conforming to XML Schemas Part 2 Datatype
5381 * Appendix F and builds an automata suitable for testing strings against
5382 * that regular expression
5383 *
5384 * Returns the compiled expression or NULL in case of error
5385 */
5386 xmlRegexpPtr
xmlRegexpCompile(const xmlChar * regexp)5387 xmlRegexpCompile(const xmlChar *regexp) {
5388 xmlRegexpPtr ret;
5389 xmlRegParserCtxtPtr ctxt;
5390
5391 ctxt = xmlRegNewParserCtxt(regexp);
5392 if (ctxt == NULL)
5393 return(NULL);
5394
5395 /* initialize the parser */
5396 ctxt->end = NULL;
5397 ctxt->start = ctxt->state = xmlRegNewState(ctxt);
5398 xmlRegStatePush(ctxt, ctxt->start);
5399
5400 /* parse the expression building an automata */
5401 xmlFAParseRegExp(ctxt, 1);
5402 if (CUR != 0) {
5403 ERROR("xmlFAParseRegExp: extra characters");
5404 }
5405 if (ctxt->error != 0) {
5406 xmlRegFreeParserCtxt(ctxt);
5407 return(NULL);
5408 }
5409 ctxt->end = ctxt->state;
5410 ctxt->start->type = XML_REGEXP_START_STATE;
5411 ctxt->end->type = XML_REGEXP_FINAL_STATE;
5412
5413 /* remove the Epsilon except for counted transitions */
5414 xmlFAEliminateEpsilonTransitions(ctxt);
5415
5416
5417 if (ctxt->error != 0) {
5418 xmlRegFreeParserCtxt(ctxt);
5419 return(NULL);
5420 }
5421 ret = xmlRegEpxFromParse(ctxt);
5422 xmlRegFreeParserCtxt(ctxt);
5423 return(ret);
5424 }
5425
5426 /**
5427 * xmlRegexpExec:
5428 * @comp: the compiled regular expression
5429 * @content: the value to check against the regular expression
5430 *
5431 * Check if the regular expression generates the value
5432 *
5433 * Returns 1 if it matches, 0 if not and a negative value in case of error
5434 */
5435 int
xmlRegexpExec(xmlRegexpPtr comp,const xmlChar * content)5436 xmlRegexpExec(xmlRegexpPtr comp, const xmlChar *content) {
5437 if ((comp == NULL) || (content == NULL))
5438 return(-1);
5439 return(xmlFARegExec(comp, content));
5440 }
5441
5442 /**
5443 * xmlRegexpIsDeterminist:
5444 * @comp: the compiled regular expression
5445 *
5446 * Check if the regular expression is determinist
5447 *
5448 * Returns 1 if it yes, 0 if not and a negative value in case of error
5449 */
5450 int
xmlRegexpIsDeterminist(xmlRegexpPtr comp)5451 xmlRegexpIsDeterminist(xmlRegexpPtr comp) {
5452 xmlAutomataPtr am;
5453 int ret;
5454
5455 if (comp == NULL)
5456 return(-1);
5457 if (comp->determinist != -1)
5458 return(comp->determinist);
5459
5460 am = xmlNewAutomata();
5461 if (am->states != NULL) {
5462 int i;
5463
5464 for (i = 0;i < am->nbStates;i++)
5465 xmlRegFreeState(am->states[i]);
5466 xmlFree(am->states);
5467 }
5468 am->nbAtoms = comp->nbAtoms;
5469 am->atoms = comp->atoms;
5470 am->nbStates = comp->nbStates;
5471 am->states = comp->states;
5472 am->determinist = -1;
5473 ret = xmlFAComputesDeterminism(am);
5474 am->atoms = NULL;
5475 am->states = NULL;
5476 xmlFreeAutomata(am);
5477 return(ret);
5478 }
5479
5480 /**
5481 * xmlRegFreeRegexp:
5482 * @regexp: the regexp
5483 *
5484 * Free a regexp
5485 */
5486 void
xmlRegFreeRegexp(xmlRegexpPtr regexp)5487 xmlRegFreeRegexp(xmlRegexpPtr regexp) {
5488 int i;
5489 if (regexp == NULL)
5490 return;
5491
5492 if (regexp->string != NULL)
5493 xmlFree(regexp->string);
5494 if (regexp->states != NULL) {
5495 for (i = 0;i < regexp->nbStates;i++)
5496 xmlRegFreeState(regexp->states[i]);
5497 xmlFree(regexp->states);
5498 }
5499 if (regexp->atoms != NULL) {
5500 for (i = 0;i < regexp->nbAtoms;i++)
5501 xmlRegFreeAtom(regexp->atoms[i]);
5502 xmlFree(regexp->atoms);
5503 }
5504 if (regexp->counters != NULL)
5505 xmlFree(regexp->counters);
5506 if (regexp->compact != NULL)
5507 xmlFree(regexp->compact);
5508 if (regexp->transdata != NULL)
5509 xmlFree(regexp->transdata);
5510 if (regexp->stringMap != NULL) {
5511 for (i = 0; i < regexp->nbstrings;i++)
5512 xmlFree(regexp->stringMap[i]);
5513 xmlFree(regexp->stringMap);
5514 }
5515
5516 xmlFree(regexp);
5517 }
5518
5519 #ifdef LIBXML_AUTOMATA_ENABLED
5520 /************************************************************************
5521 * *
5522 * The Automata interface *
5523 * *
5524 ************************************************************************/
5525
5526 /**
5527 * xmlNewAutomata:
5528 *
5529 * Create a new automata
5530 *
5531 * Returns the new object or NULL in case of failure
5532 */
5533 xmlAutomataPtr
xmlNewAutomata(void)5534 xmlNewAutomata(void) {
5535 xmlAutomataPtr ctxt;
5536
5537 ctxt = xmlRegNewParserCtxt(NULL);
5538 if (ctxt == NULL)
5539 return(NULL);
5540
5541 /* initialize the parser */
5542 ctxt->end = NULL;
5543 ctxt->start = ctxt->state = xmlRegNewState(ctxt);
5544 if (ctxt->start == NULL) {
5545 xmlFreeAutomata(ctxt);
5546 return(NULL);
5547 }
5548 ctxt->start->type = XML_REGEXP_START_STATE;
5549 if (xmlRegStatePush(ctxt, ctxt->start) < 0) {
5550 xmlRegFreeState(ctxt->start);
5551 xmlFreeAutomata(ctxt);
5552 return(NULL);
5553 }
5554
5555 return(ctxt);
5556 }
5557
5558 /**
5559 * xmlFreeAutomata:
5560 * @am: an automata
5561 *
5562 * Free an automata
5563 */
5564 void
xmlFreeAutomata(xmlAutomataPtr am)5565 xmlFreeAutomata(xmlAutomataPtr am) {
5566 if (am == NULL)
5567 return;
5568 xmlRegFreeParserCtxt(am);
5569 }
5570
5571 /**
5572 * xmlAutomataGetInitState:
5573 * @am: an automata
5574 *
5575 * Initial state lookup
5576 *
5577 * Returns the initial state of the automata
5578 */
5579 xmlAutomataStatePtr
xmlAutomataGetInitState(xmlAutomataPtr am)5580 xmlAutomataGetInitState(xmlAutomataPtr am) {
5581 if (am == NULL)
5582 return(NULL);
5583 return(am->start);
5584 }
5585
5586 /**
5587 * xmlAutomataSetFinalState:
5588 * @am: an automata
5589 * @state: a state in this automata
5590 *
5591 * Makes that state a final state
5592 *
5593 * Returns 0 or -1 in case of error
5594 */
5595 int
xmlAutomataSetFinalState(xmlAutomataPtr am,xmlAutomataStatePtr state)5596 xmlAutomataSetFinalState(xmlAutomataPtr am, xmlAutomataStatePtr state) {
5597 if ((am == NULL) || (state == NULL))
5598 return(-1);
5599 state->type = XML_REGEXP_FINAL_STATE;
5600 return(0);
5601 }
5602
5603 /**
5604 * xmlAutomataNewTransition:
5605 * @am: an automata
5606 * @from: the starting point of the transition
5607 * @to: the target point of the transition or NULL
5608 * @token: the input string associated to that transition
5609 * @data: data passed to the callback function if the transition is activated
5610 *
5611 * If @to is NULL, this creates first a new target state in the automata
5612 * and then adds a transition from the @from state to the target state
5613 * activated by the value of @token
5614 *
5615 * Returns the target state or NULL in case of error
5616 */
5617 xmlAutomataStatePtr
xmlAutomataNewTransition(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,const xmlChar * token,void * data)5618 xmlAutomataNewTransition(xmlAutomataPtr am, xmlAutomataStatePtr from,
5619 xmlAutomataStatePtr to, const xmlChar *token,
5620 void *data) {
5621 xmlRegAtomPtr atom;
5622
5623 if ((am == NULL) || (from == NULL) || (token == NULL))
5624 return(NULL);
5625 atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
5626 if (atom == NULL)
5627 return(NULL);
5628 atom->data = data;
5629 if (atom == NULL)
5630 return(NULL);
5631 atom->valuep = xmlStrdup(token);
5632
5633 if (xmlFAGenerateTransitions(am, from, to, atom) < 0) {
5634 xmlRegFreeAtom(atom);
5635 return(NULL);
5636 }
5637 if (to == NULL)
5638 return(am->state);
5639 return(to);
5640 }
5641
5642 /**
5643 * xmlAutomataNewTransition2:
5644 * @am: an automata
5645 * @from: the starting point of the transition
5646 * @to: the target point of the transition or NULL
5647 * @token: the first input string associated to that transition
5648 * @token2: the second input string associated to that transition
5649 * @data: data passed to the callback function if the transition is activated
5650 *
5651 * If @to is NULL, this creates first a new target state in the automata
5652 * and then adds a transition from the @from state to the target state
5653 * activated by the value of @token
5654 *
5655 * Returns the target state or NULL in case of error
5656 */
5657 xmlAutomataStatePtr
xmlAutomataNewTransition2(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,const xmlChar * token,const xmlChar * token2,void * data)5658 xmlAutomataNewTransition2(xmlAutomataPtr am, xmlAutomataStatePtr from,
5659 xmlAutomataStatePtr to, const xmlChar *token,
5660 const xmlChar *token2, void *data) {
5661 xmlRegAtomPtr atom;
5662
5663 if ((am == NULL) || (from == NULL) || (token == NULL))
5664 return(NULL);
5665 atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
5666 if (atom == NULL)
5667 return(NULL);
5668 atom->data = data;
5669 if ((token2 == NULL) || (*token2 == 0)) {
5670 atom->valuep = xmlStrdup(token);
5671 } else {
5672 int lenn, lenp;
5673 xmlChar *str;
5674
5675 lenn = strlen((char *) token2);
5676 lenp = strlen((char *) token);
5677
5678 str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
5679 if (str == NULL) {
5680 xmlRegFreeAtom(atom);
5681 return(NULL);
5682 }
5683 memcpy(&str[0], token, lenp);
5684 str[lenp] = '|';
5685 memcpy(&str[lenp + 1], token2, lenn);
5686 str[lenn + lenp + 1] = 0;
5687
5688 atom->valuep = str;
5689 }
5690
5691 if (xmlFAGenerateTransitions(am, from, to, atom) < 0) {
5692 xmlRegFreeAtom(atom);
5693 return(NULL);
5694 }
5695 if (to == NULL)
5696 return(am->state);
5697 return(to);
5698 }
5699
5700 /**
5701 * xmlAutomataNewNegTrans:
5702 * @am: an automata
5703 * @from: the starting point of the transition
5704 * @to: the target point of the transition or NULL
5705 * @token: the first input string associated to that transition
5706 * @token2: the second input string associated to that transition
5707 * @data: data passed to the callback function if the transition is activated
5708 *
5709 * If @to is NULL, this creates first a new target state in the automata
5710 * and then adds a transition from the @from state to the target state
5711 * activated by any value except (@token,@token2)
5712 * Note that if @token2 is not NULL, then (X, NULL) won't match to follow
5713 # the semantic of XSD ##other
5714 *
5715 * Returns the target state or NULL in case of error
5716 */
5717 xmlAutomataStatePtr
xmlAutomataNewNegTrans(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,const xmlChar * token,const xmlChar * token2,void * data)5718 xmlAutomataNewNegTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
5719 xmlAutomataStatePtr to, const xmlChar *token,
5720 const xmlChar *token2, void *data) {
5721 xmlRegAtomPtr atom;
5722 xmlChar err_msg[200];
5723
5724 if ((am == NULL) || (from == NULL) || (token == NULL))
5725 return(NULL);
5726 atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
5727 if (atom == NULL)
5728 return(NULL);
5729 atom->data = data;
5730 atom->neg = 1;
5731 if ((token2 == NULL) || (*token2 == 0)) {
5732 atom->valuep = xmlStrdup(token);
5733 } else {
5734 int lenn, lenp;
5735 xmlChar *str;
5736
5737 lenn = strlen((char *) token2);
5738 lenp = strlen((char *) token);
5739
5740 str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
5741 if (str == NULL) {
5742 xmlRegFreeAtom(atom);
5743 return(NULL);
5744 }
5745 memcpy(&str[0], token, lenp);
5746 str[lenp] = '|';
5747 memcpy(&str[lenp + 1], token2, lenn);
5748 str[lenn + lenp + 1] = 0;
5749
5750 atom->valuep = str;
5751 }
5752 snprintf((char *) err_msg, 199, "not %s", (const char *) atom->valuep);
5753 err_msg[199] = 0;
5754 atom->valuep2 = xmlStrdup(err_msg);
5755
5756 if (xmlFAGenerateTransitions(am, from, to, atom) < 0) {
5757 xmlRegFreeAtom(atom);
5758 return(NULL);
5759 }
5760 am->negs++;
5761 if (to == NULL)
5762 return(am->state);
5763 return(to);
5764 }
5765
5766 /**
5767 * xmlAutomataNewCountTrans2:
5768 * @am: an automata
5769 * @from: the starting point of the transition
5770 * @to: the target point of the transition or NULL
5771 * @token: the input string associated to that transition
5772 * @token2: the second input string associated to that transition
5773 * @min: the minimum successive occurences of token
5774 * @max: the maximum successive occurences of token
5775 * @data: data associated to the transition
5776 *
5777 * If @to is NULL, this creates first a new target state in the automata
5778 * and then adds a transition from the @from state to the target state
5779 * activated by a succession of input of value @token and @token2 and
5780 * whose number is between @min and @max
5781 *
5782 * Returns the target state or NULL in case of error
5783 */
5784 xmlAutomataStatePtr
xmlAutomataNewCountTrans2(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,const xmlChar * token,const xmlChar * token2,int min,int max,void * data)5785 xmlAutomataNewCountTrans2(xmlAutomataPtr am, xmlAutomataStatePtr from,
5786 xmlAutomataStatePtr to, const xmlChar *token,
5787 const xmlChar *token2,
5788 int min, int max, void *data) {
5789 xmlRegAtomPtr atom;
5790 int counter;
5791
5792 if ((am == NULL) || (from == NULL) || (token == NULL))
5793 return(NULL);
5794 if (min < 0)
5795 return(NULL);
5796 if ((max < min) || (max < 1))
5797 return(NULL);
5798 atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
5799 if (atom == NULL)
5800 return(NULL);
5801 if ((token2 == NULL) || (*token2 == 0)) {
5802 atom->valuep = xmlStrdup(token);
5803 } else {
5804 int lenn, lenp;
5805 xmlChar *str;
5806
5807 lenn = strlen((char *) token2);
5808 lenp = strlen((char *) token);
5809
5810 str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
5811 if (str == NULL) {
5812 xmlRegFreeAtom(atom);
5813 return(NULL);
5814 }
5815 memcpy(&str[0], token, lenp);
5816 str[lenp] = '|';
5817 memcpy(&str[lenp + 1], token2, lenn);
5818 str[lenn + lenp + 1] = 0;
5819
5820 atom->valuep = str;
5821 }
5822 atom->data = data;
5823 if (min == 0)
5824 atom->min = 1;
5825 else
5826 atom->min = min;
5827 atom->max = max;
5828
5829 /*
5830 * associate a counter to the transition.
5831 */
5832 counter = xmlRegGetCounter(am);
5833 am->counters[counter].min = min;
5834 am->counters[counter].max = max;
5835
5836 /* xmlFAGenerateTransitions(am, from, to, atom); */
5837 if (to == NULL) {
5838 to = xmlRegNewState(am);
5839 xmlRegStatePush(am, to);
5840 }
5841 xmlRegStateAddTrans(am, from, atom, to, counter, -1);
5842 xmlRegAtomPush(am, atom);
5843 am->state = to;
5844
5845 if (to == NULL)
5846 to = am->state;
5847 if (to == NULL)
5848 return(NULL);
5849 if (min == 0)
5850 xmlFAGenerateEpsilonTransition(am, from, to);
5851 return(to);
5852 }
5853
5854 /**
5855 * xmlAutomataNewCountTrans:
5856 * @am: an automata
5857 * @from: the starting point of the transition
5858 * @to: the target point of the transition or NULL
5859 * @token: the input string associated to that transition
5860 * @min: the minimum successive occurences of token
5861 * @max: the maximum successive occurences of token
5862 * @data: data associated to the transition
5863 *
5864 * If @to is NULL, this creates first a new target state in the automata
5865 * and then adds a transition from the @from state to the target state
5866 * activated by a succession of input of value @token and whose number
5867 * is between @min and @max
5868 *
5869 * Returns the target state or NULL in case of error
5870 */
5871 xmlAutomataStatePtr
xmlAutomataNewCountTrans(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,const xmlChar * token,int min,int max,void * data)5872 xmlAutomataNewCountTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
5873 xmlAutomataStatePtr to, const xmlChar *token,
5874 int min, int max, void *data) {
5875 xmlRegAtomPtr atom;
5876 int counter;
5877
5878 if ((am == NULL) || (from == NULL) || (token == NULL))
5879 return(NULL);
5880 if (min < 0)
5881 return(NULL);
5882 if ((max < min) || (max < 1))
5883 return(NULL);
5884 atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
5885 if (atom == NULL)
5886 return(NULL);
5887 atom->valuep = xmlStrdup(token);
5888 atom->data = data;
5889 if (min == 0)
5890 atom->min = 1;
5891 else
5892 atom->min = min;
5893 atom->max = max;
5894
5895 /*
5896 * associate a counter to the transition.
5897 */
5898 counter = xmlRegGetCounter(am);
5899 am->counters[counter].min = min;
5900 am->counters[counter].max = max;
5901
5902 /* xmlFAGenerateTransitions(am, from, to, atom); */
5903 if (to == NULL) {
5904 to = xmlRegNewState(am);
5905 xmlRegStatePush(am, to);
5906 }
5907 xmlRegStateAddTrans(am, from, atom, to, counter, -1);
5908 xmlRegAtomPush(am, atom);
5909 am->state = to;
5910
5911 if (to == NULL)
5912 to = am->state;
5913 if (to == NULL)
5914 return(NULL);
5915 if (min == 0)
5916 xmlFAGenerateEpsilonTransition(am, from, to);
5917 return(to);
5918 }
5919
5920 /**
5921 * xmlAutomataNewOnceTrans2:
5922 * @am: an automata
5923 * @from: the starting point of the transition
5924 * @to: the target point of the transition or NULL
5925 * @token: the input string associated to that transition
5926 * @token2: the second input string associated to that transition
5927 * @min: the minimum successive occurences of token
5928 * @max: the maximum successive occurences of token
5929 * @data: data associated to the transition
5930 *
5931 * If @to is NULL, this creates first a new target state in the automata
5932 * and then adds a transition from the @from state to the target state
5933 * activated by a succession of input of value @token and @token2 and whose
5934 * number is between @min and @max, moreover that transition can only be
5935 * crossed once.
5936 *
5937 * Returns the target state or NULL in case of error
5938 */
5939 xmlAutomataStatePtr
xmlAutomataNewOnceTrans2(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,const xmlChar * token,const xmlChar * token2,int min,int max,void * data)5940 xmlAutomataNewOnceTrans2(xmlAutomataPtr am, xmlAutomataStatePtr from,
5941 xmlAutomataStatePtr to, const xmlChar *token,
5942 const xmlChar *token2,
5943 int min, int max, void *data) {
5944 xmlRegAtomPtr atom;
5945 int counter;
5946
5947 if ((am == NULL) || (from == NULL) || (token == NULL))
5948 return(NULL);
5949 if (min < 1)
5950 return(NULL);
5951 if ((max < min) || (max < 1))
5952 return(NULL);
5953 atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
5954 if (atom == NULL)
5955 return(NULL);
5956 if ((token2 == NULL) || (*token2 == 0)) {
5957 atom->valuep = xmlStrdup(token);
5958 } else {
5959 int lenn, lenp;
5960 xmlChar *str;
5961
5962 lenn = strlen((char *) token2);
5963 lenp = strlen((char *) token);
5964
5965 str = (xmlChar *) xmlMallocAtomic(lenn + lenp + 2);
5966 if (str == NULL) {
5967 xmlRegFreeAtom(atom);
5968 return(NULL);
5969 }
5970 memcpy(&str[0], token, lenp);
5971 str[lenp] = '|';
5972 memcpy(&str[lenp + 1], token2, lenn);
5973 str[lenn + lenp + 1] = 0;
5974
5975 atom->valuep = str;
5976 }
5977 atom->data = data;
5978 atom->quant = XML_REGEXP_QUANT_ONCEONLY;
5979 atom->min = min;
5980 atom->max = max;
5981 /*
5982 * associate a counter to the transition.
5983 */
5984 counter = xmlRegGetCounter(am);
5985 am->counters[counter].min = 1;
5986 am->counters[counter].max = 1;
5987
5988 /* xmlFAGenerateTransitions(am, from, to, atom); */
5989 if (to == NULL) {
5990 to = xmlRegNewState(am);
5991 xmlRegStatePush(am, to);
5992 }
5993 xmlRegStateAddTrans(am, from, atom, to, counter, -1);
5994 xmlRegAtomPush(am, atom);
5995 am->state = to;
5996 return(to);
5997 }
5998
5999
6000
6001 /**
6002 * xmlAutomataNewOnceTrans:
6003 * @am: an automata
6004 * @from: the starting point of the transition
6005 * @to: the target point of the transition or NULL
6006 * @token: the input string associated to that transition
6007 * @min: the minimum successive occurences of token
6008 * @max: the maximum successive occurences of token
6009 * @data: data associated to the transition
6010 *
6011 * If @to is NULL, this creates first a new target state in the automata
6012 * and then adds a transition from the @from state to the target state
6013 * activated by a succession of input of value @token and whose number
6014 * is between @min and @max, moreover that transition can only be crossed
6015 * once.
6016 *
6017 * Returns the target state or NULL in case of error
6018 */
6019 xmlAutomataStatePtr
xmlAutomataNewOnceTrans(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,const xmlChar * token,int min,int max,void * data)6020 xmlAutomataNewOnceTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
6021 xmlAutomataStatePtr to, const xmlChar *token,
6022 int min, int max, void *data) {
6023 xmlRegAtomPtr atom;
6024 int counter;
6025
6026 if ((am == NULL) || (from == NULL) || (token == NULL))
6027 return(NULL);
6028 if (min < 1)
6029 return(NULL);
6030 if ((max < min) || (max < 1))
6031 return(NULL);
6032 atom = xmlRegNewAtom(am, XML_REGEXP_STRING);
6033 if (atom == NULL)
6034 return(NULL);
6035 atom->valuep = xmlStrdup(token);
6036 atom->data = data;
6037 atom->quant = XML_REGEXP_QUANT_ONCEONLY;
6038 atom->min = min;
6039 atom->max = max;
6040 /*
6041 * associate a counter to the transition.
6042 */
6043 counter = xmlRegGetCounter(am);
6044 am->counters[counter].min = 1;
6045 am->counters[counter].max = 1;
6046
6047 /* xmlFAGenerateTransitions(am, from, to, atom); */
6048 if (to == NULL) {
6049 to = xmlRegNewState(am);
6050 xmlRegStatePush(am, to);
6051 }
6052 xmlRegStateAddTrans(am, from, atom, to, counter, -1);
6053 xmlRegAtomPush(am, atom);
6054 am->state = to;
6055 return(to);
6056 }
6057
6058 /**
6059 * xmlAutomataNewState:
6060 * @am: an automata
6061 *
6062 * Create a new disconnected state in the automata
6063 *
6064 * Returns the new state or NULL in case of error
6065 */
6066 xmlAutomataStatePtr
xmlAutomataNewState(xmlAutomataPtr am)6067 xmlAutomataNewState(xmlAutomataPtr am) {
6068 xmlAutomataStatePtr to;
6069
6070 if (am == NULL)
6071 return(NULL);
6072 to = xmlRegNewState(am);
6073 xmlRegStatePush(am, to);
6074 return(to);
6075 }
6076
6077 /**
6078 * xmlAutomataNewEpsilon:
6079 * @am: an automata
6080 * @from: the starting point of the transition
6081 * @to: the target point of the transition or NULL
6082 *
6083 * If @to is NULL, this creates first a new target state in the automata
6084 * and then adds an epsilon transition from the @from state to the
6085 * target state
6086 *
6087 * Returns the target state or NULL in case of error
6088 */
6089 xmlAutomataStatePtr
xmlAutomataNewEpsilon(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to)6090 xmlAutomataNewEpsilon(xmlAutomataPtr am, xmlAutomataStatePtr from,
6091 xmlAutomataStatePtr to) {
6092 if ((am == NULL) || (from == NULL))
6093 return(NULL);
6094 xmlFAGenerateEpsilonTransition(am, from, to);
6095 if (to == NULL)
6096 return(am->state);
6097 return(to);
6098 }
6099
6100 /**
6101 * xmlAutomataNewAllTrans:
6102 * @am: an automata
6103 * @from: the starting point of the transition
6104 * @to: the target point of the transition or NULL
6105 * @lax: allow to transition if not all all transitions have been activated
6106 *
6107 * If @to is NULL, this creates first a new target state in the automata
6108 * and then adds a an ALL transition from the @from state to the
6109 * target state. That transition is an epsilon transition allowed only when
6110 * all transitions from the @from node have been activated.
6111 *
6112 * Returns the target state or NULL in case of error
6113 */
6114 xmlAutomataStatePtr
xmlAutomataNewAllTrans(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,int lax)6115 xmlAutomataNewAllTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
6116 xmlAutomataStatePtr to, int lax) {
6117 if ((am == NULL) || (from == NULL))
6118 return(NULL);
6119 xmlFAGenerateAllTransition(am, from, to, lax);
6120 if (to == NULL)
6121 return(am->state);
6122 return(to);
6123 }
6124
6125 /**
6126 * xmlAutomataNewCounter:
6127 * @am: an automata
6128 * @min: the minimal value on the counter
6129 * @max: the maximal value on the counter
6130 *
6131 * Create a new counter
6132 *
6133 * Returns the counter number or -1 in case of error
6134 */
6135 int
xmlAutomataNewCounter(xmlAutomataPtr am,int min,int max)6136 xmlAutomataNewCounter(xmlAutomataPtr am, int min, int max) {
6137 int ret;
6138
6139 if (am == NULL)
6140 return(-1);
6141
6142 ret = xmlRegGetCounter(am);
6143 if (ret < 0)
6144 return(-1);
6145 am->counters[ret].min = min;
6146 am->counters[ret].max = max;
6147 return(ret);
6148 }
6149
6150 /**
6151 * xmlAutomataNewCountedTrans:
6152 * @am: an automata
6153 * @from: the starting point of the transition
6154 * @to: the target point of the transition or NULL
6155 * @counter: the counter associated to that transition
6156 *
6157 * If @to is NULL, this creates first a new target state in the automata
6158 * and then adds an epsilon transition from the @from state to the target state
6159 * which will increment the counter provided
6160 *
6161 * Returns the target state or NULL in case of error
6162 */
6163 xmlAutomataStatePtr
xmlAutomataNewCountedTrans(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,int counter)6164 xmlAutomataNewCountedTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
6165 xmlAutomataStatePtr to, int counter) {
6166 if ((am == NULL) || (from == NULL) || (counter < 0))
6167 return(NULL);
6168 xmlFAGenerateCountedEpsilonTransition(am, from, to, counter);
6169 if (to == NULL)
6170 return(am->state);
6171 return(to);
6172 }
6173
6174 /**
6175 * xmlAutomataNewCounterTrans:
6176 * @am: an automata
6177 * @from: the starting point of the transition
6178 * @to: the target point of the transition or NULL
6179 * @counter: the counter associated to that transition
6180 *
6181 * If @to is NULL, this creates first a new target state in the automata
6182 * and then adds an epsilon transition from the @from state to the target state
6183 * which will be allowed only if the counter is within the right range.
6184 *
6185 * Returns the target state or NULL in case of error
6186 */
6187 xmlAutomataStatePtr
xmlAutomataNewCounterTrans(xmlAutomataPtr am,xmlAutomataStatePtr from,xmlAutomataStatePtr to,int counter)6188 xmlAutomataNewCounterTrans(xmlAutomataPtr am, xmlAutomataStatePtr from,
6189 xmlAutomataStatePtr to, int counter) {
6190 if ((am == NULL) || (from == NULL) || (counter < 0))
6191 return(NULL);
6192 xmlFAGenerateCountedTransition(am, from, to, counter);
6193 if (to == NULL)
6194 return(am->state);
6195 return(to);
6196 }
6197
6198 /**
6199 * xmlAutomataCompile:
6200 * @am: an automata
6201 *
6202 * Compile the automata into a Reg Exp ready for being executed.
6203 * The automata should be free after this point.
6204 *
6205 * Returns the compiled regexp or NULL in case of error
6206 */
6207 xmlRegexpPtr
xmlAutomataCompile(xmlAutomataPtr am)6208 xmlAutomataCompile(xmlAutomataPtr am) {
6209 xmlRegexpPtr ret;
6210
6211 if ((am == NULL) || (am->error != 0)) return(NULL);
6212 xmlFAEliminateEpsilonTransitions(am);
6213 /* xmlFAComputesDeterminism(am); */
6214 ret = xmlRegEpxFromParse(am);
6215
6216 return(ret);
6217 }
6218
6219 /**
6220 * xmlAutomataIsDeterminist:
6221 * @am: an automata
6222 *
6223 * Checks if an automata is determinist.
6224 *
6225 * Returns 1 if true, 0 if not, and -1 in case of error
6226 */
6227 int
xmlAutomataIsDeterminist(xmlAutomataPtr am)6228 xmlAutomataIsDeterminist(xmlAutomataPtr am) {
6229 int ret;
6230
6231 if (am == NULL)
6232 return(-1);
6233
6234 ret = xmlFAComputesDeterminism(am);
6235 return(ret);
6236 }
6237 #endif /* LIBXML_AUTOMATA_ENABLED */
6238
6239 #ifdef LIBXML_EXPR_ENABLED
6240 /************************************************************************
6241 * *
6242 * Formal Expression handling code *
6243 * *
6244 ************************************************************************/
6245 /************************************************************************
6246 * *
6247 * Expression handling context *
6248 * *
6249 ************************************************************************/
6250
6251 struct _xmlExpCtxt {
6252 xmlDictPtr dict;
6253 xmlExpNodePtr *table;
6254 int size;
6255 int nbElems;
6256 int nb_nodes;
6257 const char *expr;
6258 const char *cur;
6259 int nb_cons;
6260 int tabSize;
6261 };
6262
6263 /**
6264 * xmlExpNewCtxt:
6265 * @maxNodes: the maximum number of nodes
6266 * @dict: optional dictionnary to use internally
6267 *
6268 * Creates a new context for manipulating expressions
6269 *
6270 * Returns the context or NULL in case of error
6271 */
6272 xmlExpCtxtPtr
xmlExpNewCtxt(int maxNodes,xmlDictPtr dict)6273 xmlExpNewCtxt(int maxNodes, xmlDictPtr dict) {
6274 xmlExpCtxtPtr ret;
6275 int size = 256;
6276
6277 if (maxNodes <= 4096)
6278 maxNodes = 4096;
6279
6280 ret = (xmlExpCtxtPtr) xmlMalloc(sizeof(xmlExpCtxt));
6281 if (ret == NULL)
6282 return(NULL);
6283 memset(ret, 0, sizeof(xmlExpCtxt));
6284 ret->size = size;
6285 ret->nbElems = 0;
6286 ret->table = xmlMalloc(size * sizeof(xmlExpNodePtr));
6287 if (ret->table == NULL) {
6288 xmlFree(ret);
6289 return(NULL);
6290 }
6291 memset(ret->table, 0, size * sizeof(xmlExpNodePtr));
6292 if (dict == NULL) {
6293 ret->dict = xmlDictCreate();
6294 if (ret->dict == NULL) {
6295 xmlFree(ret->table);
6296 xmlFree(ret);
6297 return(NULL);
6298 }
6299 } else {
6300 ret->dict = dict;
6301 xmlDictReference(ret->dict);
6302 }
6303 return(ret);
6304 }
6305
6306 /**
6307 * xmlExpFreeCtxt:
6308 * @ctxt: an expression context
6309 *
6310 * Free an expression context
6311 */
6312 void
xmlExpFreeCtxt(xmlExpCtxtPtr ctxt)6313 xmlExpFreeCtxt(xmlExpCtxtPtr ctxt) {
6314 if (ctxt == NULL)
6315 return;
6316 xmlDictFree(ctxt->dict);
6317 if (ctxt->table != NULL)
6318 xmlFree(ctxt->table);
6319 xmlFree(ctxt);
6320 }
6321
6322 /************************************************************************
6323 * *
6324 * Structure associated to an expression node *
6325 * *
6326 ************************************************************************/
6327 #define MAX_NODES 10000
6328
6329 /* #define DEBUG_DERIV */
6330
6331 /*
6332 * TODO:
6333 * - Wildcards
6334 * - public API for creation
6335 *
6336 * Started
6337 * - regression testing
6338 *
6339 * Done
6340 * - split into module and test tool
6341 * - memleaks
6342 */
6343
6344 typedef enum {
6345 XML_EXP_NILABLE = (1 << 0)
6346 } xmlExpNodeInfo;
6347
6348 #define IS_NILLABLE(node) ((node)->info & XML_EXP_NILABLE)
6349
6350 struct _xmlExpNode {
6351 unsigned char type;/* xmlExpNodeType */
6352 unsigned char info;/* OR of xmlExpNodeInfo */
6353 unsigned short key; /* the hash key */
6354 unsigned int ref; /* The number of references */
6355 int c_max; /* the maximum length it can consume */
6356 xmlExpNodePtr exp_left;
6357 xmlExpNodePtr next;/* the next node in the hash table or free list */
6358 union {
6359 struct {
6360 int f_min;
6361 int f_max;
6362 } count;
6363 struct {
6364 xmlExpNodePtr f_right;
6365 } children;
6366 const xmlChar *f_str;
6367 } field;
6368 };
6369
6370 #define exp_min field.count.f_min
6371 #define exp_max field.count.f_max
6372 /* #define exp_left field.children.f_left */
6373 #define exp_right field.children.f_right
6374 #define exp_str field.f_str
6375
6376 static xmlExpNodePtr xmlExpNewNode(xmlExpCtxtPtr ctxt, xmlExpNodeType type);
6377 static xmlExpNode forbiddenExpNode = {
6378 XML_EXP_FORBID, 0, 0, 0, 0, NULL, NULL, {{ 0, 0}}
6379 };
6380 xmlExpNodePtr forbiddenExp = &forbiddenExpNode;
6381 static xmlExpNode emptyExpNode = {
6382 XML_EXP_EMPTY, 1, 0, 0, 0, NULL, NULL, {{ 0, 0}}
6383 };
6384 xmlExpNodePtr emptyExp = &emptyExpNode;
6385
6386 /************************************************************************
6387 * *
6388 * The custom hash table for unicity and canonicalization *
6389 * of sub-expressions pointers *
6390 * *
6391 ************************************************************************/
6392 /*
6393 * xmlExpHashNameComputeKey:
6394 * Calculate the hash key for a token
6395 */
6396 static unsigned short
xmlExpHashNameComputeKey(const xmlChar * name)6397 xmlExpHashNameComputeKey(const xmlChar *name) {
6398 unsigned short value = 0L;
6399 char ch;
6400
6401 if (name != NULL) {
6402 value += 30 * (*name);
6403 while ((ch = *name++) != 0) {
6404 value = value ^ ((value << 5) + (value >> 3) + (unsigned short)ch);
6405 }
6406 }
6407 return (value);
6408 }
6409
6410 /*
6411 * xmlExpHashComputeKey:
6412 * Calculate the hash key for a compound expression
6413 */
6414 static unsigned short
xmlExpHashComputeKey(xmlExpNodeType type,xmlExpNodePtr left,xmlExpNodePtr right)6415 xmlExpHashComputeKey(xmlExpNodeType type, xmlExpNodePtr left,
6416 xmlExpNodePtr right) {
6417 unsigned long value;
6418 unsigned short ret;
6419
6420 switch (type) {
6421 case XML_EXP_SEQ:
6422 value = left->key;
6423 value += right->key;
6424 value *= 3;
6425 ret = (unsigned short) value;
6426 break;
6427 case XML_EXP_OR:
6428 value = left->key;
6429 value += right->key;
6430 value *= 7;
6431 ret = (unsigned short) value;
6432 break;
6433 case XML_EXP_COUNT:
6434 value = left->key;
6435 value += right->key;
6436 ret = (unsigned short) value;
6437 break;
6438 default:
6439 ret = 0;
6440 }
6441 return(ret);
6442 }
6443
6444
6445 static xmlExpNodePtr
xmlExpNewNode(xmlExpCtxtPtr ctxt,xmlExpNodeType type)6446 xmlExpNewNode(xmlExpCtxtPtr ctxt, xmlExpNodeType type) {
6447 xmlExpNodePtr ret;
6448
6449 if (ctxt->nb_nodes >= MAX_NODES)
6450 return(NULL);
6451 ret = (xmlExpNodePtr) xmlMalloc(sizeof(xmlExpNode));
6452 if (ret == NULL)
6453 return(NULL);
6454 memset(ret, 0, sizeof(xmlExpNode));
6455 ret->type = type;
6456 ret->next = NULL;
6457 ctxt->nb_nodes++;
6458 ctxt->nb_cons++;
6459 return(ret);
6460 }
6461
6462 /**
6463 * xmlExpHashGetEntry:
6464 * @table: the hash table
6465 *
6466 * Get the unique entry from the hash table. The entry is created if
6467 * needed. @left and @right are consumed, i.e. their ref count will
6468 * be decremented by the operation.
6469 *
6470 * Returns the pointer or NULL in case of error
6471 */
6472 static xmlExpNodePtr
xmlExpHashGetEntry(xmlExpCtxtPtr ctxt,xmlExpNodeType type,xmlExpNodePtr left,xmlExpNodePtr right,const xmlChar * name,int min,int max)6473 xmlExpHashGetEntry(xmlExpCtxtPtr ctxt, xmlExpNodeType type,
6474 xmlExpNodePtr left, xmlExpNodePtr right,
6475 const xmlChar *name, int min, int max) {
6476 unsigned short kbase, key;
6477 xmlExpNodePtr entry;
6478 xmlExpNodePtr insert;
6479
6480 if (ctxt == NULL)
6481 return(NULL);
6482
6483 /*
6484 * Check for duplicate and insertion location.
6485 */
6486 if (type == XML_EXP_ATOM) {
6487 kbase = xmlExpHashNameComputeKey(name);
6488 } else if (type == XML_EXP_COUNT) {
6489 /* COUNT reduction rule 1 */
6490 /* a{1} -> a */
6491 if (min == max) {
6492 if (min == 1) {
6493 return(left);
6494 }
6495 if (min == 0) {
6496 xmlExpFree(ctxt, left);
6497 return(emptyExp);
6498 }
6499 }
6500 if (min < 0) {
6501 xmlExpFree(ctxt, left);
6502 return(forbiddenExp);
6503 }
6504 if (max == -1)
6505 kbase = min + 79;
6506 else
6507 kbase = max - min;
6508 kbase += left->key;
6509 } else if (type == XML_EXP_OR) {
6510 /* Forbid reduction rules */
6511 if (left->type == XML_EXP_FORBID) {
6512 xmlExpFree(ctxt, left);
6513 return(right);
6514 }
6515 if (right->type == XML_EXP_FORBID) {
6516 xmlExpFree(ctxt, right);
6517 return(left);
6518 }
6519
6520 /* OR reduction rule 1 */
6521 /* a | a reduced to a */
6522 if (left == right) {
6523 left->ref--;
6524 return(left);
6525 }
6526 /* OR canonicalization rule 1 */
6527 /* linearize (a | b) | c into a | (b | c) */
6528 if ((left->type == XML_EXP_OR) && (right->type != XML_EXP_OR)) {
6529 xmlExpNodePtr tmp = left;
6530 left = right;
6531 right = tmp;
6532 }
6533 /* OR reduction rule 2 */
6534 /* a | (a | b) and b | (a | b) are reduced to a | b */
6535 if (right->type == XML_EXP_OR) {
6536 if ((left == right->exp_left) ||
6537 (left == right->exp_right)) {
6538 xmlExpFree(ctxt, left);
6539 return(right);
6540 }
6541 }
6542 /* OR canonicalization rule 2 */
6543 /* linearize (a | b) | c into a | (b | c) */
6544 if (left->type == XML_EXP_OR) {
6545 xmlExpNodePtr tmp;
6546
6547 /* OR canonicalization rule 2 */
6548 if ((left->exp_right->type != XML_EXP_OR) &&
6549 (left->exp_right->key < left->exp_left->key)) {
6550 tmp = left->exp_right;
6551 left->exp_right = left->exp_left;
6552 left->exp_left = tmp;
6553 }
6554 left->exp_right->ref++;
6555 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left->exp_right, right,
6556 NULL, 0, 0);
6557 left->exp_left->ref++;
6558 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left->exp_left, tmp,
6559 NULL, 0, 0);
6560
6561 xmlExpFree(ctxt, left);
6562 return(tmp);
6563 }
6564 if (right->type == XML_EXP_OR) {
6565 /* Ordering in the tree */
6566 /* C | (A | B) -> A | (B | C) */
6567 if (left->key > right->exp_right->key) {
6568 xmlExpNodePtr tmp;
6569 right->exp_right->ref++;
6570 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_right,
6571 left, NULL, 0, 0);
6572 right->exp_left->ref++;
6573 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_left,
6574 tmp, NULL, 0, 0);
6575 xmlExpFree(ctxt, right);
6576 return(tmp);
6577 }
6578 /* Ordering in the tree */
6579 /* B | (A | C) -> A | (B | C) */
6580 if (left->key > right->exp_left->key) {
6581 xmlExpNodePtr tmp;
6582 right->exp_right->ref++;
6583 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, left,
6584 right->exp_right, NULL, 0, 0);
6585 right->exp_left->ref++;
6586 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_OR, right->exp_left,
6587 tmp, NULL, 0, 0);
6588 xmlExpFree(ctxt, right);
6589 return(tmp);
6590 }
6591 }
6592 /* we know both types are != XML_EXP_OR here */
6593 else if (left->key > right->key) {
6594 xmlExpNodePtr tmp = left;
6595 left = right;
6596 right = tmp;
6597 }
6598 kbase = xmlExpHashComputeKey(type, left, right);
6599 } else if (type == XML_EXP_SEQ) {
6600 /* Forbid reduction rules */
6601 if (left->type == XML_EXP_FORBID) {
6602 xmlExpFree(ctxt, right);
6603 return(left);
6604 }
6605 if (right->type == XML_EXP_FORBID) {
6606 xmlExpFree(ctxt, left);
6607 return(right);
6608 }
6609 /* Empty reduction rules */
6610 if (right->type == XML_EXP_EMPTY) {
6611 return(left);
6612 }
6613 if (left->type == XML_EXP_EMPTY) {
6614 return(right);
6615 }
6616 kbase = xmlExpHashComputeKey(type, left, right);
6617 } else
6618 return(NULL);
6619
6620 key = kbase % ctxt->size;
6621 if (ctxt->table[key] != NULL) {
6622 for (insert = ctxt->table[key]; insert != NULL;
6623 insert = insert->next) {
6624 if ((insert->key == kbase) &&
6625 (insert->type == type)) {
6626 if (type == XML_EXP_ATOM) {
6627 if (name == insert->exp_str) {
6628 insert->ref++;
6629 return(insert);
6630 }
6631 } else if (type == XML_EXP_COUNT) {
6632 if ((insert->exp_min == min) && (insert->exp_max == max) &&
6633 (insert->exp_left == left)) {
6634 insert->ref++;
6635 left->ref--;
6636 return(insert);
6637 }
6638 } else if ((insert->exp_left == left) &&
6639 (insert->exp_right == right)) {
6640 insert->ref++;
6641 left->ref--;
6642 right->ref--;
6643 return(insert);
6644 }
6645 }
6646 }
6647 }
6648
6649 entry = xmlExpNewNode(ctxt, type);
6650 if (entry == NULL)
6651 return(NULL);
6652 entry->key = kbase;
6653 if (type == XML_EXP_ATOM) {
6654 entry->exp_str = name;
6655 entry->c_max = 1;
6656 } else if (type == XML_EXP_COUNT) {
6657 entry->exp_min = min;
6658 entry->exp_max = max;
6659 entry->exp_left = left;
6660 if ((min == 0) || (IS_NILLABLE(left)))
6661 entry->info |= XML_EXP_NILABLE;
6662 if (max < 0)
6663 entry->c_max = -1;
6664 else
6665 entry->c_max = max * entry->exp_left->c_max;
6666 } else {
6667 entry->exp_left = left;
6668 entry->exp_right = right;
6669 if (type == XML_EXP_OR) {
6670 if ((IS_NILLABLE(left)) || (IS_NILLABLE(right)))
6671 entry->info |= XML_EXP_NILABLE;
6672 if ((entry->exp_left->c_max == -1) ||
6673 (entry->exp_right->c_max == -1))
6674 entry->c_max = -1;
6675 else if (entry->exp_left->c_max > entry->exp_right->c_max)
6676 entry->c_max = entry->exp_left->c_max;
6677 else
6678 entry->c_max = entry->exp_right->c_max;
6679 } else {
6680 if ((IS_NILLABLE(left)) && (IS_NILLABLE(right)))
6681 entry->info |= XML_EXP_NILABLE;
6682 if ((entry->exp_left->c_max == -1) ||
6683 (entry->exp_right->c_max == -1))
6684 entry->c_max = -1;
6685 else
6686 entry->c_max = entry->exp_left->c_max + entry->exp_right->c_max;
6687 }
6688 }
6689 entry->ref = 1;
6690 if (ctxt->table[key] != NULL)
6691 entry->next = ctxt->table[key];
6692
6693 ctxt->table[key] = entry;
6694 ctxt->nbElems++;
6695
6696 return(entry);
6697 }
6698
6699 /**
6700 * xmlExpFree:
6701 * @ctxt: the expression context
6702 * @exp: the expression
6703 *
6704 * Dereference the expression
6705 */
6706 void
xmlExpFree(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp)6707 xmlExpFree(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp) {
6708 if ((exp == NULL) || (exp == forbiddenExp) || (exp == emptyExp))
6709 return;
6710 exp->ref--;
6711 if (exp->ref == 0) {
6712 unsigned short key;
6713
6714 /* Unlink it first from the hash table */
6715 key = exp->key % ctxt->size;
6716 if (ctxt->table[key] == exp) {
6717 ctxt->table[key] = exp->next;
6718 } else {
6719 xmlExpNodePtr tmp;
6720
6721 tmp = ctxt->table[key];
6722 while (tmp != NULL) {
6723 if (tmp->next == exp) {
6724 tmp->next = exp->next;
6725 break;
6726 }
6727 tmp = tmp->next;
6728 }
6729 }
6730
6731 if ((exp->type == XML_EXP_SEQ) || (exp->type == XML_EXP_OR)) {
6732 xmlExpFree(ctxt, exp->exp_left);
6733 xmlExpFree(ctxt, exp->exp_right);
6734 } else if (exp->type == XML_EXP_COUNT) {
6735 xmlExpFree(ctxt, exp->exp_left);
6736 }
6737 xmlFree(exp);
6738 ctxt->nb_nodes--;
6739 }
6740 }
6741
6742 /**
6743 * xmlExpRef:
6744 * @exp: the expression
6745 *
6746 * Increase the reference count of the expression
6747 */
6748 void
xmlExpRef(xmlExpNodePtr exp)6749 xmlExpRef(xmlExpNodePtr exp) {
6750 if (exp != NULL)
6751 exp->ref++;
6752 }
6753
6754 /**
6755 * xmlExpNewAtom:
6756 * @ctxt: the expression context
6757 * @name: the atom name
6758 * @len: the atom name lenght in byte (or -1);
6759 *
6760 * Get the atom associated to this name from that context
6761 *
6762 * Returns the node or NULL in case of error
6763 */
6764 xmlExpNodePtr
xmlExpNewAtom(xmlExpCtxtPtr ctxt,const xmlChar * name,int len)6765 xmlExpNewAtom(xmlExpCtxtPtr ctxt, const xmlChar *name, int len) {
6766 if ((ctxt == NULL) || (name == NULL))
6767 return(NULL);
6768 name = xmlDictLookup(ctxt->dict, name, len);
6769 if (name == NULL)
6770 return(NULL);
6771 return(xmlExpHashGetEntry(ctxt, XML_EXP_ATOM, NULL, NULL, name, 0, 0));
6772 }
6773
6774 /**
6775 * xmlExpNewOr:
6776 * @ctxt: the expression context
6777 * @left: left expression
6778 * @right: right expression
6779 *
6780 * Get the atom associated to the choice @left | @right
6781 * Note that @left and @right are consumed in the operation, to keep
6782 * an handle on them use xmlExpRef() and use xmlExpFree() to release them,
6783 * this is true even in case of failure (unless ctxt == NULL).
6784 *
6785 * Returns the node or NULL in case of error
6786 */
6787 xmlExpNodePtr
xmlExpNewOr(xmlExpCtxtPtr ctxt,xmlExpNodePtr left,xmlExpNodePtr right)6788 xmlExpNewOr(xmlExpCtxtPtr ctxt, xmlExpNodePtr left, xmlExpNodePtr right) {
6789 if (ctxt == NULL)
6790 return(NULL);
6791 if ((left == NULL) || (right == NULL)) {
6792 xmlExpFree(ctxt, left);
6793 xmlExpFree(ctxt, right);
6794 return(NULL);
6795 }
6796 return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, left, right, NULL, 0, 0));
6797 }
6798
6799 /**
6800 * xmlExpNewSeq:
6801 * @ctxt: the expression context
6802 * @left: left expression
6803 * @right: right expression
6804 *
6805 * Get the atom associated to the sequence @left , @right
6806 * Note that @left and @right are consumed in the operation, to keep
6807 * an handle on them use xmlExpRef() and use xmlExpFree() to release them,
6808 * this is true even in case of failure (unless ctxt == NULL).
6809 *
6810 * Returns the node or NULL in case of error
6811 */
6812 xmlExpNodePtr
xmlExpNewSeq(xmlExpCtxtPtr ctxt,xmlExpNodePtr left,xmlExpNodePtr right)6813 xmlExpNewSeq(xmlExpCtxtPtr ctxt, xmlExpNodePtr left, xmlExpNodePtr right) {
6814 if (ctxt == NULL)
6815 return(NULL);
6816 if ((left == NULL) || (right == NULL)) {
6817 xmlExpFree(ctxt, left);
6818 xmlExpFree(ctxt, right);
6819 return(NULL);
6820 }
6821 return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, left, right, NULL, 0, 0));
6822 }
6823
6824 /**
6825 * xmlExpNewRange:
6826 * @ctxt: the expression context
6827 * @subset: the expression to be repeated
6828 * @min: the lower bound for the repetition
6829 * @max: the upper bound for the repetition, -1 means infinite
6830 *
6831 * Get the atom associated to the range (@subset){@min, @max}
6832 * Note that @subset is consumed in the operation, to keep
6833 * an handle on it use xmlExpRef() and use xmlExpFree() to release it,
6834 * this is true even in case of failure (unless ctxt == NULL).
6835 *
6836 * Returns the node or NULL in case of error
6837 */
6838 xmlExpNodePtr
xmlExpNewRange(xmlExpCtxtPtr ctxt,xmlExpNodePtr subset,int min,int max)6839 xmlExpNewRange(xmlExpCtxtPtr ctxt, xmlExpNodePtr subset, int min, int max) {
6840 if (ctxt == NULL)
6841 return(NULL);
6842 if ((subset == NULL) || (min < 0) || (max < -1) ||
6843 ((max >= 0) && (min > max))) {
6844 xmlExpFree(ctxt, subset);
6845 return(NULL);
6846 }
6847 return(xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, subset,
6848 NULL, NULL, min, max));
6849 }
6850
6851 /************************************************************************
6852 * *
6853 * Public API for operations on expressions *
6854 * *
6855 ************************************************************************/
6856
6857 static int
xmlExpGetLanguageInt(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,const xmlChar ** list,int len,int nb)6858 xmlExpGetLanguageInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
6859 const xmlChar**list, int len, int nb) {
6860 int tmp, tmp2;
6861 tail:
6862 switch (exp->type) {
6863 case XML_EXP_EMPTY:
6864 return(0);
6865 case XML_EXP_ATOM:
6866 for (tmp = 0;tmp < nb;tmp++)
6867 if (list[tmp] == exp->exp_str)
6868 return(0);
6869 if (nb >= len)
6870 return(-2);
6871 list[nb++] = exp->exp_str;
6872 return(1);
6873 case XML_EXP_COUNT:
6874 exp = exp->exp_left;
6875 goto tail;
6876 case XML_EXP_SEQ:
6877 case XML_EXP_OR:
6878 tmp = xmlExpGetLanguageInt(ctxt, exp->exp_left, list, len, nb);
6879 if (tmp < 0)
6880 return(tmp);
6881 tmp2 = xmlExpGetLanguageInt(ctxt, exp->exp_right, list, len,
6882 nb + tmp);
6883 if (tmp2 < 0)
6884 return(tmp2);
6885 return(tmp + tmp2);
6886 }
6887 return(-1);
6888 }
6889
6890 /**
6891 * xmlExpGetLanguage:
6892 * @ctxt: the expression context
6893 * @exp: the expression
6894 * @langList: where to store the tokens
6895 * @len: the allocated lenght of @list
6896 *
6897 * Find all the strings used in @exp and store them in @list
6898 *
6899 * Returns the number of unique strings found, -1 in case of errors and
6900 * -2 if there is more than @len strings
6901 */
6902 int
xmlExpGetLanguage(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,const xmlChar ** langList,int len)6903 xmlExpGetLanguage(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
6904 const xmlChar**langList, int len) {
6905 if ((ctxt == NULL) || (exp == NULL) || (langList == NULL) || (len <= 0))
6906 return(-1);
6907 return(xmlExpGetLanguageInt(ctxt, exp, langList, len, 0));
6908 }
6909
6910 static int
xmlExpGetStartInt(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,const xmlChar ** list,int len,int nb)6911 xmlExpGetStartInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
6912 const xmlChar**list, int len, int nb) {
6913 int tmp, tmp2;
6914 tail:
6915 switch (exp->type) {
6916 case XML_EXP_FORBID:
6917 return(0);
6918 case XML_EXP_EMPTY:
6919 return(0);
6920 case XML_EXP_ATOM:
6921 for (tmp = 0;tmp < nb;tmp++)
6922 if (list[tmp] == exp->exp_str)
6923 return(0);
6924 if (nb >= len)
6925 return(-2);
6926 list[nb++] = exp->exp_str;
6927 return(1);
6928 case XML_EXP_COUNT:
6929 exp = exp->exp_left;
6930 goto tail;
6931 case XML_EXP_SEQ:
6932 tmp = xmlExpGetStartInt(ctxt, exp->exp_left, list, len, nb);
6933 if (tmp < 0)
6934 return(tmp);
6935 if (IS_NILLABLE(exp->exp_left)) {
6936 tmp2 = xmlExpGetStartInt(ctxt, exp->exp_right, list, len,
6937 nb + tmp);
6938 if (tmp2 < 0)
6939 return(tmp2);
6940 tmp += tmp2;
6941 }
6942 return(tmp);
6943 case XML_EXP_OR:
6944 tmp = xmlExpGetStartInt(ctxt, exp->exp_left, list, len, nb);
6945 if (tmp < 0)
6946 return(tmp);
6947 tmp2 = xmlExpGetStartInt(ctxt, exp->exp_right, list, len,
6948 nb + tmp);
6949 if (tmp2 < 0)
6950 return(tmp2);
6951 return(tmp + tmp2);
6952 }
6953 return(-1);
6954 }
6955
6956 /**
6957 * xmlExpGetStart:
6958 * @ctxt: the expression context
6959 * @exp: the expression
6960 * @tokList: where to store the tokens
6961 * @len: the allocated lenght of @list
6962 *
6963 * Find all the strings that appears at the start of the languages
6964 * accepted by @exp and store them in @list. E.g. for (a, b) | c
6965 * it will return the list [a, c]
6966 *
6967 * Returns the number of unique strings found, -1 in case of errors and
6968 * -2 if there is more than @len strings
6969 */
6970 int
xmlExpGetStart(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,const xmlChar ** tokList,int len)6971 xmlExpGetStart(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
6972 const xmlChar**tokList, int len) {
6973 if ((ctxt == NULL) || (exp == NULL) || (tokList == NULL) || (len <= 0))
6974 return(-1);
6975 return(xmlExpGetStartInt(ctxt, exp, tokList, len, 0));
6976 }
6977
6978 /**
6979 * xmlExpIsNillable:
6980 * @exp: the expression
6981 *
6982 * Finds if the expression is nillable, i.e. if it accepts the empty sequqnce
6983 *
6984 * Returns 1 if nillable, 0 if not and -1 in case of error
6985 */
6986 int
xmlExpIsNillable(xmlExpNodePtr exp)6987 xmlExpIsNillable(xmlExpNodePtr exp) {
6988 if (exp == NULL)
6989 return(-1);
6990 return(IS_NILLABLE(exp) != 0);
6991 }
6992
6993 static xmlExpNodePtr
xmlExpStringDeriveInt(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,const xmlChar * str)6994 xmlExpStringDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, const xmlChar *str)
6995 {
6996 xmlExpNodePtr ret;
6997
6998 switch (exp->type) {
6999 case XML_EXP_EMPTY:
7000 return(forbiddenExp);
7001 case XML_EXP_FORBID:
7002 return(forbiddenExp);
7003 case XML_EXP_ATOM:
7004 if (exp->exp_str == str) {
7005 #ifdef DEBUG_DERIV
7006 printf("deriv atom: equal => Empty\n");
7007 #endif
7008 ret = emptyExp;
7009 } else {
7010 #ifdef DEBUG_DERIV
7011 printf("deriv atom: mismatch => forbid\n");
7012 #endif
7013 /* TODO wildcards here */
7014 ret = forbiddenExp;
7015 }
7016 return(ret);
7017 case XML_EXP_OR: {
7018 xmlExpNodePtr tmp;
7019
7020 #ifdef DEBUG_DERIV
7021 printf("deriv or: => or(derivs)\n");
7022 #endif
7023 tmp = xmlExpStringDeriveInt(ctxt, exp->exp_left, str);
7024 if (tmp == NULL) {
7025 return(NULL);
7026 }
7027 ret = xmlExpStringDeriveInt(ctxt, exp->exp_right, str);
7028 if (ret == NULL) {
7029 xmlExpFree(ctxt, tmp);
7030 return(NULL);
7031 }
7032 ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, tmp, ret,
7033 NULL, 0, 0);
7034 return(ret);
7035 }
7036 case XML_EXP_SEQ:
7037 #ifdef DEBUG_DERIV
7038 printf("deriv seq: starting with left\n");
7039 #endif
7040 ret = xmlExpStringDeriveInt(ctxt, exp->exp_left, str);
7041 if (ret == NULL) {
7042 return(NULL);
7043 } else if (ret == forbiddenExp) {
7044 if (IS_NILLABLE(exp->exp_left)) {
7045 #ifdef DEBUG_DERIV
7046 printf("deriv seq: left failed but nillable\n");
7047 #endif
7048 ret = xmlExpStringDeriveInt(ctxt, exp->exp_right, str);
7049 }
7050 } else {
7051 #ifdef DEBUG_DERIV
7052 printf("deriv seq: left match => sequence\n");
7053 #endif
7054 exp->exp_right->ref++;
7055 ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, exp->exp_right,
7056 NULL, 0, 0);
7057 }
7058 return(ret);
7059 case XML_EXP_COUNT: {
7060 int min, max;
7061 xmlExpNodePtr tmp;
7062
7063 if (exp->exp_max == 0)
7064 return(forbiddenExp);
7065 ret = xmlExpStringDeriveInt(ctxt, exp->exp_left, str);
7066 if (ret == NULL)
7067 return(NULL);
7068 if (ret == forbiddenExp) {
7069 #ifdef DEBUG_DERIV
7070 printf("deriv count: pattern mismatch => forbid\n");
7071 #endif
7072 return(ret);
7073 }
7074 if (exp->exp_max == 1)
7075 return(ret);
7076 if (exp->exp_max < 0) /* unbounded */
7077 max = -1;
7078 else
7079 max = exp->exp_max - 1;
7080 if (exp->exp_min > 0)
7081 min = exp->exp_min - 1;
7082 else
7083 min = 0;
7084 exp->exp_left->ref++;
7085 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left, NULL,
7086 NULL, min, max);
7087 if (ret == emptyExp) {
7088 #ifdef DEBUG_DERIV
7089 printf("deriv count: match to empty => new count\n");
7090 #endif
7091 return(tmp);
7092 }
7093 #ifdef DEBUG_DERIV
7094 printf("deriv count: match => sequence with new count\n");
7095 #endif
7096 return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, tmp,
7097 NULL, 0, 0));
7098 }
7099 }
7100 return(NULL);
7101 }
7102
7103 /**
7104 * xmlExpStringDerive:
7105 * @ctxt: the expression context
7106 * @exp: the expression
7107 * @str: the string
7108 * @len: the string len in bytes if available
7109 *
7110 * Do one step of Brzozowski derivation of the expression @exp with
7111 * respect to the input string
7112 *
7113 * Returns the resulting expression or NULL in case of internal error
7114 */
7115 xmlExpNodePtr
xmlExpStringDerive(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,const xmlChar * str,int len)7116 xmlExpStringDerive(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
7117 const xmlChar *str, int len) {
7118 const xmlChar *input;
7119
7120 if ((exp == NULL) || (ctxt == NULL) || (str == NULL)) {
7121 return(NULL);
7122 }
7123 /*
7124 * check the string is in the dictionnary, if yes use an interned
7125 * copy, otherwise we know it's not an acceptable input
7126 */
7127 input = xmlDictExists(ctxt->dict, str, len);
7128 if (input == NULL) {
7129 return(forbiddenExp);
7130 }
7131 return(xmlExpStringDeriveInt(ctxt, exp, input));
7132 }
7133
7134 static int
xmlExpCheckCard(xmlExpNodePtr exp,xmlExpNodePtr sub)7135 xmlExpCheckCard(xmlExpNodePtr exp, xmlExpNodePtr sub) {
7136 int ret = 1;
7137
7138 if (sub->c_max == -1) {
7139 if (exp->c_max != -1)
7140 ret = 0;
7141 } else if ((exp->c_max >= 0) && (exp->c_max < sub->c_max)) {
7142 ret = 0;
7143 }
7144 #if 0
7145 if ((IS_NILLABLE(sub)) && (!IS_NILLABLE(exp)))
7146 ret = 0;
7147 #endif
7148 return(ret);
7149 }
7150
7151 static xmlExpNodePtr xmlExpExpDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp,
7152 xmlExpNodePtr sub);
7153 /**
7154 * xmlExpDivide:
7155 * @ctxt: the expressions context
7156 * @exp: the englobing expression
7157 * @sub: the subexpression
7158 * @mult: the multiple expression
7159 * @remain: the remain from the derivation of the multiple
7160 *
7161 * Check if exp is a multiple of sub, i.e. if there is a finite number n
7162 * so that sub{n} subsume exp
7163 *
7164 * Returns the multiple value if successful, 0 if it is not a multiple
7165 * and -1 in case of internel error.
7166 */
7167
7168 static int
xmlExpDivide(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,xmlExpNodePtr sub,xmlExpNodePtr * mult,xmlExpNodePtr * remain)7169 xmlExpDivide(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub,
7170 xmlExpNodePtr *mult, xmlExpNodePtr *remain) {
7171 int i;
7172 xmlExpNodePtr tmp, tmp2;
7173
7174 if (mult != NULL) *mult = NULL;
7175 if (remain != NULL) *remain = NULL;
7176 if (exp->c_max == -1) return(0);
7177 if (IS_NILLABLE(exp) && (!IS_NILLABLE(sub))) return(0);
7178
7179 for (i = 1;i <= exp->c_max;i++) {
7180 sub->ref++;
7181 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT,
7182 sub, NULL, NULL, i, i);
7183 if (tmp == NULL) {
7184 return(-1);
7185 }
7186 if (!xmlExpCheckCard(tmp, exp)) {
7187 xmlExpFree(ctxt, tmp);
7188 continue;
7189 }
7190 tmp2 = xmlExpExpDeriveInt(ctxt, tmp, exp);
7191 if (tmp2 == NULL) {
7192 xmlExpFree(ctxt, tmp);
7193 return(-1);
7194 }
7195 if ((tmp2 != forbiddenExp) && (IS_NILLABLE(tmp2))) {
7196 if (remain != NULL)
7197 *remain = tmp2;
7198 else
7199 xmlExpFree(ctxt, tmp2);
7200 if (mult != NULL)
7201 *mult = tmp;
7202 else
7203 xmlExpFree(ctxt, tmp);
7204 #ifdef DEBUG_DERIV
7205 printf("Divide succeeded %d\n", i);
7206 #endif
7207 return(i);
7208 }
7209 xmlExpFree(ctxt, tmp);
7210 xmlExpFree(ctxt, tmp2);
7211 }
7212 #ifdef DEBUG_DERIV
7213 printf("Divide failed\n");
7214 #endif
7215 return(0);
7216 }
7217
7218 /**
7219 * xmlExpExpDeriveInt:
7220 * @ctxt: the expressions context
7221 * @exp: the englobing expression
7222 * @sub: the subexpression
7223 *
7224 * Try to do a step of Brzozowski derivation but at a higher level
7225 * the input being a subexpression.
7226 *
7227 * Returns the resulting expression or NULL in case of internal error
7228 */
7229 static xmlExpNodePtr
xmlExpExpDeriveInt(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,xmlExpNodePtr sub)7230 xmlExpExpDeriveInt(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) {
7231 xmlExpNodePtr ret, tmp, tmp2, tmp3;
7232 const xmlChar **tab;
7233 int len, i;
7234
7235 /*
7236 * In case of equality and if the expression can only consume a finite
7237 * amount, then the derivation is empty
7238 */
7239 if ((exp == sub) && (exp->c_max >= 0)) {
7240 #ifdef DEBUG_DERIV
7241 printf("Equal(exp, sub) and finite -> Empty\n");
7242 #endif
7243 return(emptyExp);
7244 }
7245 /*
7246 * decompose sub sequence first
7247 */
7248 if (sub->type == XML_EXP_EMPTY) {
7249 #ifdef DEBUG_DERIV
7250 printf("Empty(sub) -> Empty\n");
7251 #endif
7252 exp->ref++;
7253 return(exp);
7254 }
7255 if (sub->type == XML_EXP_SEQ) {
7256 #ifdef DEBUG_DERIV
7257 printf("Seq(sub) -> decompose\n");
7258 #endif
7259 tmp = xmlExpExpDeriveInt(ctxt, exp, sub->exp_left);
7260 if (tmp == NULL)
7261 return(NULL);
7262 if (tmp == forbiddenExp)
7263 return(tmp);
7264 ret = xmlExpExpDeriveInt(ctxt, tmp, sub->exp_right);
7265 xmlExpFree(ctxt, tmp);
7266 return(ret);
7267 }
7268 if (sub->type == XML_EXP_OR) {
7269 #ifdef DEBUG_DERIV
7270 printf("Or(sub) -> decompose\n");
7271 #endif
7272 tmp = xmlExpExpDeriveInt(ctxt, exp, sub->exp_left);
7273 if (tmp == forbiddenExp)
7274 return(tmp);
7275 if (tmp == NULL)
7276 return(NULL);
7277 ret = xmlExpExpDeriveInt(ctxt, exp, sub->exp_right);
7278 if ((ret == NULL) || (ret == forbiddenExp)) {
7279 xmlExpFree(ctxt, tmp);
7280 return(ret);
7281 }
7282 return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, tmp, ret, NULL, 0, 0));
7283 }
7284 if (!xmlExpCheckCard(exp, sub)) {
7285 #ifdef DEBUG_DERIV
7286 printf("CheckCard(exp, sub) failed -> Forbid\n");
7287 #endif
7288 return(forbiddenExp);
7289 }
7290 switch (exp->type) {
7291 case XML_EXP_EMPTY:
7292 if (sub == emptyExp)
7293 return(emptyExp);
7294 #ifdef DEBUG_DERIV
7295 printf("Empty(exp) -> Forbid\n");
7296 #endif
7297 return(forbiddenExp);
7298 case XML_EXP_FORBID:
7299 #ifdef DEBUG_DERIV
7300 printf("Forbid(exp) -> Forbid\n");
7301 #endif
7302 return(forbiddenExp);
7303 case XML_EXP_ATOM:
7304 if (sub->type == XML_EXP_ATOM) {
7305 /* TODO: handle wildcards */
7306 if (exp->exp_str == sub->exp_str) {
7307 #ifdef DEBUG_DERIV
7308 printf("Atom match -> Empty\n");
7309 #endif
7310 return(emptyExp);
7311 }
7312 #ifdef DEBUG_DERIV
7313 printf("Atom mismatch -> Forbid\n");
7314 #endif
7315 return(forbiddenExp);
7316 }
7317 if ((sub->type == XML_EXP_COUNT) &&
7318 (sub->exp_max == 1) &&
7319 (sub->exp_left->type == XML_EXP_ATOM)) {
7320 /* TODO: handle wildcards */
7321 if (exp->exp_str == sub->exp_left->exp_str) {
7322 #ifdef DEBUG_DERIV
7323 printf("Atom match -> Empty\n");
7324 #endif
7325 return(emptyExp);
7326 }
7327 #ifdef DEBUG_DERIV
7328 printf("Atom mismatch -> Forbid\n");
7329 #endif
7330 return(forbiddenExp);
7331 }
7332 #ifdef DEBUG_DERIV
7333 printf("Compex exp vs Atom -> Forbid\n");
7334 #endif
7335 return(forbiddenExp);
7336 case XML_EXP_SEQ:
7337 /* try to get the sequence consumed only if possible */
7338 if (xmlExpCheckCard(exp->exp_left, sub)) {
7339 /* See if the sequence can be consumed directly */
7340 #ifdef DEBUG_DERIV
7341 printf("Seq trying left only\n");
7342 #endif
7343 ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub);
7344 if ((ret != forbiddenExp) && (ret != NULL)) {
7345 #ifdef DEBUG_DERIV
7346 printf("Seq trying left only worked\n");
7347 #endif
7348 /*
7349 * TODO: assumption here that we are determinist
7350 * i.e. we won't get to a nillable exp left
7351 * subset which could be matched by the right
7352 * part too.
7353 * e.g.: (a | b)+,(a | c) and 'a+,a'
7354 */
7355 exp->exp_right->ref++;
7356 return(xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret,
7357 exp->exp_right, NULL, 0, 0));
7358 }
7359 #ifdef DEBUG_DERIV
7360 } else {
7361 printf("Seq: left too short\n");
7362 #endif
7363 }
7364 /* Try instead to decompose */
7365 if (sub->type == XML_EXP_COUNT) {
7366 int min, max;
7367
7368 #ifdef DEBUG_DERIV
7369 printf("Seq: sub is a count\n");
7370 #endif
7371 ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub->exp_left);
7372 if (ret == NULL)
7373 return(NULL);
7374 if (ret != forbiddenExp) {
7375 #ifdef DEBUG_DERIV
7376 printf("Seq , Count match on left\n");
7377 #endif
7378 if (sub->exp_max < 0)
7379 max = -1;
7380 else
7381 max = sub->exp_max -1;
7382 if (sub->exp_min > 0)
7383 min = sub->exp_min -1;
7384 else
7385 min = 0;
7386 exp->exp_right->ref++;
7387 tmp = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret,
7388 exp->exp_right, NULL, 0, 0);
7389 if (tmp == NULL)
7390 return(NULL);
7391
7392 sub->exp_left->ref++;
7393 tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT,
7394 sub->exp_left, NULL, NULL, min, max);
7395 if (tmp2 == NULL) {
7396 xmlExpFree(ctxt, tmp);
7397 return(NULL);
7398 }
7399 ret = xmlExpExpDeriveInt(ctxt, tmp, tmp2);
7400 xmlExpFree(ctxt, tmp);
7401 xmlExpFree(ctxt, tmp2);
7402 return(ret);
7403 }
7404 }
7405 /* we made no progress on structured operations */
7406 break;
7407 case XML_EXP_OR:
7408 #ifdef DEBUG_DERIV
7409 printf("Or , trying both side\n");
7410 #endif
7411 ret = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub);
7412 if (ret == NULL)
7413 return(NULL);
7414 tmp = xmlExpExpDeriveInt(ctxt, exp->exp_right, sub);
7415 if (tmp == NULL) {
7416 xmlExpFree(ctxt, ret);
7417 return(NULL);
7418 }
7419 return(xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, tmp, NULL, 0, 0));
7420 case XML_EXP_COUNT: {
7421 int min, max;
7422
7423 if (sub->type == XML_EXP_COUNT) {
7424 /*
7425 * Try to see if the loop is completely subsumed
7426 */
7427 tmp = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub->exp_left);
7428 if (tmp == NULL)
7429 return(NULL);
7430 if (tmp == forbiddenExp) {
7431 int mult;
7432
7433 #ifdef DEBUG_DERIV
7434 printf("Count, Count inner don't subsume\n");
7435 #endif
7436 mult = xmlExpDivide(ctxt, sub->exp_left, exp->exp_left,
7437 NULL, &tmp);
7438 if (mult <= 0) {
7439 #ifdef DEBUG_DERIV
7440 printf("Count, Count not multiple => forbidden\n");
7441 #endif
7442 return(forbiddenExp);
7443 }
7444 if (sub->exp_max == -1) {
7445 max = -1;
7446 if (exp->exp_max == -1) {
7447 if (exp->exp_min <= sub->exp_min * mult)
7448 min = 0;
7449 else
7450 min = exp->exp_min - sub->exp_min * mult;
7451 } else {
7452 #ifdef DEBUG_DERIV
7453 printf("Count, Count finite can't subsume infinite\n");
7454 #endif
7455 xmlExpFree(ctxt, tmp);
7456 return(forbiddenExp);
7457 }
7458 } else {
7459 if (exp->exp_max == -1) {
7460 #ifdef DEBUG_DERIV
7461 printf("Infinite loop consume mult finite loop\n");
7462 #endif
7463 if (exp->exp_min > sub->exp_min * mult) {
7464 max = -1;
7465 min = exp->exp_min - sub->exp_min * mult;
7466 } else {
7467 max = -1;
7468 min = 0;
7469 }
7470 } else {
7471 if (exp->exp_max < sub->exp_max * mult) {
7472 #ifdef DEBUG_DERIV
7473 printf("loops max mult mismatch => forbidden\n");
7474 #endif
7475 xmlExpFree(ctxt, tmp);
7476 return(forbiddenExp);
7477 }
7478 if (sub->exp_max * mult > exp->exp_min)
7479 min = 0;
7480 else
7481 min = exp->exp_min - sub->exp_max * mult;
7482 max = exp->exp_max - sub->exp_max * mult;
7483 }
7484 }
7485 } else if (!IS_NILLABLE(tmp)) {
7486 /*
7487 * TODO: loop here to try to grow if working on finite
7488 * blocks.
7489 */
7490 #ifdef DEBUG_DERIV
7491 printf("Count, Count remain not nillable => forbidden\n");
7492 #endif
7493 xmlExpFree(ctxt, tmp);
7494 return(forbiddenExp);
7495 } else if (sub->exp_max == -1) {
7496 if (exp->exp_max == -1) {
7497 if (exp->exp_min <= sub->exp_min) {
7498 #ifdef DEBUG_DERIV
7499 printf("Infinite loops Okay => COUNT(0,Inf)\n");
7500 #endif
7501 max = -1;
7502 min = 0;
7503 } else {
7504 #ifdef DEBUG_DERIV
7505 printf("Infinite loops min => Count(X,Inf)\n");
7506 #endif
7507 max = -1;
7508 min = exp->exp_min - sub->exp_min;
7509 }
7510 } else if (exp->exp_min > sub->exp_min) {
7511 #ifdef DEBUG_DERIV
7512 printf("loops min mismatch 1 => forbidden ???\n");
7513 #endif
7514 xmlExpFree(ctxt, tmp);
7515 return(forbiddenExp);
7516 } else {
7517 max = -1;
7518 min = 0;
7519 }
7520 } else {
7521 if (exp->exp_max == -1) {
7522 #ifdef DEBUG_DERIV
7523 printf("Infinite loop consume finite loop\n");
7524 #endif
7525 if (exp->exp_min > sub->exp_min) {
7526 max = -1;
7527 min = exp->exp_min - sub->exp_min;
7528 } else {
7529 max = -1;
7530 min = 0;
7531 }
7532 } else {
7533 if (exp->exp_max < sub->exp_max) {
7534 #ifdef DEBUG_DERIV
7535 printf("loops max mismatch => forbidden\n");
7536 #endif
7537 xmlExpFree(ctxt, tmp);
7538 return(forbiddenExp);
7539 }
7540 if (sub->exp_max > exp->exp_min)
7541 min = 0;
7542 else
7543 min = exp->exp_min - sub->exp_max;
7544 max = exp->exp_max - sub->exp_max;
7545 }
7546 }
7547 #ifdef DEBUG_DERIV
7548 printf("loops match => SEQ(COUNT())\n");
7549 #endif
7550 exp->exp_left->ref++;
7551 tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left,
7552 NULL, NULL, min, max);
7553 if (tmp2 == NULL) {
7554 return(NULL);
7555 }
7556 ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, tmp, tmp2,
7557 NULL, 0, 0);
7558 return(ret);
7559 }
7560 tmp = xmlExpExpDeriveInt(ctxt, exp->exp_left, sub);
7561 if (tmp == NULL)
7562 return(NULL);
7563 if (tmp == forbiddenExp) {
7564 #ifdef DEBUG_DERIV
7565 printf("loop mismatch => forbidden\n");
7566 #endif
7567 return(forbiddenExp);
7568 }
7569 if (exp->exp_min > 0)
7570 min = exp->exp_min - 1;
7571 else
7572 min = 0;
7573 if (exp->exp_max < 0)
7574 max = -1;
7575 else
7576 max = exp->exp_max - 1;
7577
7578 #ifdef DEBUG_DERIV
7579 printf("loop match => SEQ(COUNT())\n");
7580 #endif
7581 exp->exp_left->ref++;
7582 tmp2 = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, exp->exp_left,
7583 NULL, NULL, min, max);
7584 if (tmp2 == NULL)
7585 return(NULL);
7586 ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, tmp, tmp2,
7587 NULL, 0, 0);
7588 return(ret);
7589 }
7590 }
7591
7592 #ifdef DEBUG_DERIV
7593 printf("Fallback to derivative\n");
7594 #endif
7595 if (IS_NILLABLE(sub)) {
7596 if (!(IS_NILLABLE(exp)))
7597 return(forbiddenExp);
7598 else
7599 ret = emptyExp;
7600 } else
7601 ret = NULL;
7602 /*
7603 * here the structured derivation made no progress so
7604 * we use the default token based derivation to force one more step
7605 */
7606 if (ctxt->tabSize == 0)
7607 ctxt->tabSize = 40;
7608
7609 tab = (const xmlChar **) xmlMalloc(ctxt->tabSize *
7610 sizeof(const xmlChar *));
7611 if (tab == NULL) {
7612 return(NULL);
7613 }
7614
7615 /*
7616 * collect all the strings accepted by the subexpression on input
7617 */
7618 len = xmlExpGetStartInt(ctxt, sub, tab, ctxt->tabSize, 0);
7619 while (len < 0) {
7620 const xmlChar **temp;
7621 temp = (const xmlChar **) xmlRealloc((xmlChar **) tab, ctxt->tabSize * 2 *
7622 sizeof(const xmlChar *));
7623 if (temp == NULL) {
7624 xmlFree((xmlChar **) tab);
7625 return(NULL);
7626 }
7627 tab = temp;
7628 ctxt->tabSize *= 2;
7629 len = xmlExpGetStartInt(ctxt, sub, tab, ctxt->tabSize, 0);
7630 }
7631 for (i = 0;i < len;i++) {
7632 tmp = xmlExpStringDeriveInt(ctxt, exp, tab[i]);
7633 if ((tmp == NULL) || (tmp == forbiddenExp)) {
7634 xmlExpFree(ctxt, ret);
7635 xmlFree((xmlChar **) tab);
7636 return(tmp);
7637 }
7638 tmp2 = xmlExpStringDeriveInt(ctxt, sub, tab[i]);
7639 if ((tmp2 == NULL) || (tmp2 == forbiddenExp)) {
7640 xmlExpFree(ctxt, tmp);
7641 xmlExpFree(ctxt, ret);
7642 xmlFree((xmlChar **) tab);
7643 return(tmp);
7644 }
7645 tmp3 = xmlExpExpDeriveInt(ctxt, tmp, tmp2);
7646 xmlExpFree(ctxt, tmp);
7647 xmlExpFree(ctxt, tmp2);
7648
7649 if ((tmp3 == NULL) || (tmp3 == forbiddenExp)) {
7650 xmlExpFree(ctxt, ret);
7651 xmlFree((xmlChar **) tab);
7652 return(tmp3);
7653 }
7654
7655 if (ret == NULL)
7656 ret = tmp3;
7657 else {
7658 ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, tmp3, NULL, 0, 0);
7659 if (ret == NULL) {
7660 xmlFree((xmlChar **) tab);
7661 return(NULL);
7662 }
7663 }
7664 }
7665 xmlFree((xmlChar **) tab);
7666 return(ret);
7667 }
7668
7669 /**
7670 * xmlExpExpDerive:
7671 * @ctxt: the expressions context
7672 * @exp: the englobing expression
7673 * @sub: the subexpression
7674 *
7675 * Evaluates the expression resulting from @exp consuming a sub expression @sub
7676 * Based on algebraic derivation and sometimes direct Brzozowski derivation
7677 * it usually tatkes less than linear time and can handle expressions generating
7678 * infinite languages.
7679 *
7680 * Returns the resulting expression or NULL in case of internal error, the
7681 * result must be freed
7682 */
7683 xmlExpNodePtr
xmlExpExpDerive(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,xmlExpNodePtr sub)7684 xmlExpExpDerive(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) {
7685 if ((exp == NULL) || (ctxt == NULL) || (sub == NULL))
7686 return(NULL);
7687
7688 /*
7689 * O(1) speedups
7690 */
7691 if (IS_NILLABLE(sub) && (!IS_NILLABLE(exp))) {
7692 #ifdef DEBUG_DERIV
7693 printf("Sub nillable and not exp : can't subsume\n");
7694 #endif
7695 return(forbiddenExp);
7696 }
7697 if (xmlExpCheckCard(exp, sub) == 0) {
7698 #ifdef DEBUG_DERIV
7699 printf("sub generate longuer sequances than exp : can't subsume\n");
7700 #endif
7701 return(forbiddenExp);
7702 }
7703 return(xmlExpExpDeriveInt(ctxt, exp, sub));
7704 }
7705
7706 /**
7707 * xmlExpSubsume:
7708 * @ctxt: the expressions context
7709 * @exp: the englobing expression
7710 * @sub: the subexpression
7711 *
7712 * Check whether @exp accepts all the languages accexpted by @sub
7713 * the input being a subexpression.
7714 *
7715 * Returns 1 if true 0 if false and -1 in case of failure.
7716 */
7717 int
xmlExpSubsume(xmlExpCtxtPtr ctxt,xmlExpNodePtr exp,xmlExpNodePtr sub)7718 xmlExpSubsume(xmlExpCtxtPtr ctxt, xmlExpNodePtr exp, xmlExpNodePtr sub) {
7719 xmlExpNodePtr tmp;
7720
7721 if ((exp == NULL) || (ctxt == NULL) || (sub == NULL))
7722 return(-1);
7723
7724 /*
7725 * TODO: speedup by checking the language of sub is a subset of the
7726 * language of exp
7727 */
7728 /*
7729 * O(1) speedups
7730 */
7731 if (IS_NILLABLE(sub) && (!IS_NILLABLE(exp))) {
7732 #ifdef DEBUG_DERIV
7733 printf("Sub nillable and not exp : can't subsume\n");
7734 #endif
7735 return(0);
7736 }
7737 if (xmlExpCheckCard(exp, sub) == 0) {
7738 #ifdef DEBUG_DERIV
7739 printf("sub generate longuer sequances than exp : can't subsume\n");
7740 #endif
7741 return(0);
7742 }
7743 tmp = xmlExpExpDeriveInt(ctxt, exp, sub);
7744 #ifdef DEBUG_DERIV
7745 printf("Result derivation :\n");
7746 PRINT_EXP(tmp);
7747 #endif
7748 if (tmp == NULL)
7749 return(-1);
7750 if (tmp == forbiddenExp)
7751 return(0);
7752 if (tmp == emptyExp)
7753 return(1);
7754 if ((tmp != NULL) && (IS_NILLABLE(tmp))) {
7755 xmlExpFree(ctxt, tmp);
7756 return(1);
7757 }
7758 xmlExpFree(ctxt, tmp);
7759 return(0);
7760 }
7761
7762 /************************************************************************
7763 * *
7764 * Parsing expression *
7765 * *
7766 ************************************************************************/
7767
7768 static xmlExpNodePtr xmlExpParseExpr(xmlExpCtxtPtr ctxt);
7769
7770 #undef CUR
7771 #define CUR (*ctxt->cur)
7772 #undef NEXT
7773 #define NEXT ctxt->cur++;
7774 #undef IS_BLANK
7775 #define IS_BLANK(c) ((c == ' ') || (c == '\n') || (c == '\r') || (c == '\t'))
7776 #define SKIP_BLANKS while (IS_BLANK(*ctxt->cur)) ctxt->cur++;
7777
7778 static int
xmlExpParseNumber(xmlExpCtxtPtr ctxt)7779 xmlExpParseNumber(xmlExpCtxtPtr ctxt) {
7780 int ret = 0;
7781
7782 SKIP_BLANKS
7783 if (CUR == '*') {
7784 NEXT
7785 return(-1);
7786 }
7787 if ((CUR < '0') || (CUR > '9'))
7788 return(-1);
7789 while ((CUR >= '0') && (CUR <= '9')) {
7790 ret = ret * 10 + (CUR - '0');
7791 NEXT
7792 }
7793 return(ret);
7794 }
7795
7796 static xmlExpNodePtr
xmlExpParseOr(xmlExpCtxtPtr ctxt)7797 xmlExpParseOr(xmlExpCtxtPtr ctxt) {
7798 const char *base;
7799 xmlExpNodePtr ret;
7800 const xmlChar *val;
7801
7802 SKIP_BLANKS
7803 base = ctxt->cur;
7804 if (*ctxt->cur == '(') {
7805 NEXT
7806 ret = xmlExpParseExpr(ctxt);
7807 SKIP_BLANKS
7808 if (*ctxt->cur != ')') {
7809 fprintf(stderr, "unbalanced '(' : %s\n", base);
7810 xmlExpFree(ctxt, ret);
7811 return(NULL);
7812 }
7813 NEXT;
7814 SKIP_BLANKS
7815 goto parse_quantifier;
7816 }
7817 while ((CUR != 0) && (!(IS_BLANK(CUR))) && (CUR != '(') &&
7818 (CUR != ')') && (CUR != '|') && (CUR != ',') && (CUR != '{') &&
7819 (CUR != '*') && (CUR != '+') && (CUR != '?') && (CUR != '}'))
7820 NEXT;
7821 val = xmlDictLookup(ctxt->dict, BAD_CAST base, ctxt->cur - base);
7822 if (val == NULL)
7823 return(NULL);
7824 ret = xmlExpHashGetEntry(ctxt, XML_EXP_ATOM, NULL, NULL, val, 0, 0);
7825 if (ret == NULL)
7826 return(NULL);
7827 SKIP_BLANKS
7828 parse_quantifier:
7829 if (CUR == '{') {
7830 int min, max;
7831
7832 NEXT
7833 min = xmlExpParseNumber(ctxt);
7834 if (min < 0) {
7835 xmlExpFree(ctxt, ret);
7836 return(NULL);
7837 }
7838 SKIP_BLANKS
7839 if (CUR == ',') {
7840 NEXT
7841 max = xmlExpParseNumber(ctxt);
7842 SKIP_BLANKS
7843 } else
7844 max = min;
7845 if (CUR != '}') {
7846 xmlExpFree(ctxt, ret);
7847 return(NULL);
7848 }
7849 NEXT
7850 ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
7851 min, max);
7852 SKIP_BLANKS
7853 } else if (CUR == '?') {
7854 NEXT
7855 ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
7856 0, 1);
7857 SKIP_BLANKS
7858 } else if (CUR == '+') {
7859 NEXT
7860 ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
7861 1, -1);
7862 SKIP_BLANKS
7863 } else if (CUR == '*') {
7864 NEXT
7865 ret = xmlExpHashGetEntry(ctxt, XML_EXP_COUNT, ret, NULL, NULL,
7866 0, -1);
7867 SKIP_BLANKS
7868 }
7869 return(ret);
7870 }
7871
7872
7873 static xmlExpNodePtr
xmlExpParseSeq(xmlExpCtxtPtr ctxt)7874 xmlExpParseSeq(xmlExpCtxtPtr ctxt) {
7875 xmlExpNodePtr ret, right;
7876
7877 ret = xmlExpParseOr(ctxt);
7878 SKIP_BLANKS
7879 while (CUR == '|') {
7880 NEXT
7881 right = xmlExpParseOr(ctxt);
7882 if (right == NULL) {
7883 xmlExpFree(ctxt, ret);
7884 return(NULL);
7885 }
7886 ret = xmlExpHashGetEntry(ctxt, XML_EXP_OR, ret, right, NULL, 0, 0);
7887 if (ret == NULL)
7888 return(NULL);
7889 }
7890 return(ret);
7891 }
7892
7893 static xmlExpNodePtr
xmlExpParseExpr(xmlExpCtxtPtr ctxt)7894 xmlExpParseExpr(xmlExpCtxtPtr ctxt) {
7895 xmlExpNodePtr ret, right;
7896
7897 ret = xmlExpParseSeq(ctxt);
7898 SKIP_BLANKS
7899 while (CUR == ',') {
7900 NEXT
7901 right = xmlExpParseSeq(ctxt);
7902 if (right == NULL) {
7903 xmlExpFree(ctxt, ret);
7904 return(NULL);
7905 }
7906 ret = xmlExpHashGetEntry(ctxt, XML_EXP_SEQ, ret, right, NULL, 0, 0);
7907 if (ret == NULL)
7908 return(NULL);
7909 }
7910 return(ret);
7911 }
7912
7913 /**
7914 * xmlExpParse:
7915 * @ctxt: the expressions context
7916 * @expr: the 0 terminated string
7917 *
7918 * Minimal parser for regexps, it understand the following constructs
7919 * - string terminals
7920 * - choice operator |
7921 * - sequence operator ,
7922 * - subexpressions (...)
7923 * - usual cardinality operators + * and ?
7924 * - finite sequences { min, max }
7925 * - infinite sequences { min, * }
7926 * There is minimal checkings made especially no checking on strings values
7927 *
7928 * Returns a new expression or NULL in case of failure
7929 */
7930 xmlExpNodePtr
xmlExpParse(xmlExpCtxtPtr ctxt,const char * expr)7931 xmlExpParse(xmlExpCtxtPtr ctxt, const char *expr) {
7932 xmlExpNodePtr ret;
7933
7934 ctxt->expr = expr;
7935 ctxt->cur = expr;
7936
7937 ret = xmlExpParseExpr(ctxt);
7938 SKIP_BLANKS
7939 if (*ctxt->cur != 0) {
7940 xmlExpFree(ctxt, ret);
7941 return(NULL);
7942 }
7943 return(ret);
7944 }
7945
7946 static void
xmlExpDumpInt(xmlBufferPtr buf,xmlExpNodePtr expr,int glob)7947 xmlExpDumpInt(xmlBufferPtr buf, xmlExpNodePtr expr, int glob) {
7948 xmlExpNodePtr c;
7949
7950 if (expr == NULL) return;
7951 if (glob) xmlBufferWriteChar(buf, "(");
7952 switch (expr->type) {
7953 case XML_EXP_EMPTY:
7954 xmlBufferWriteChar(buf, "empty");
7955 break;
7956 case XML_EXP_FORBID:
7957 xmlBufferWriteChar(buf, "forbidden");
7958 break;
7959 case XML_EXP_ATOM:
7960 xmlBufferWriteCHAR(buf, expr->exp_str);
7961 break;
7962 case XML_EXP_SEQ:
7963 c = expr->exp_left;
7964 if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
7965 xmlExpDumpInt(buf, c, 1);
7966 else
7967 xmlExpDumpInt(buf, c, 0);
7968 xmlBufferWriteChar(buf, " , ");
7969 c = expr->exp_right;
7970 if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
7971 xmlExpDumpInt(buf, c, 1);
7972 else
7973 xmlExpDumpInt(buf, c, 0);
7974 break;
7975 case XML_EXP_OR:
7976 c = expr->exp_left;
7977 if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
7978 xmlExpDumpInt(buf, c, 1);
7979 else
7980 xmlExpDumpInt(buf, c, 0);
7981 xmlBufferWriteChar(buf, " | ");
7982 c = expr->exp_right;
7983 if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
7984 xmlExpDumpInt(buf, c, 1);
7985 else
7986 xmlExpDumpInt(buf, c, 0);
7987 break;
7988 case XML_EXP_COUNT: {
7989 char rep[40];
7990
7991 c = expr->exp_left;
7992 if ((c->type == XML_EXP_SEQ) || (c->type == XML_EXP_OR))
7993 xmlExpDumpInt(buf, c, 1);
7994 else
7995 xmlExpDumpInt(buf, c, 0);
7996 if ((expr->exp_min == 0) && (expr->exp_max == 1)) {
7997 rep[0] = '?';
7998 rep[1] = 0;
7999 } else if ((expr->exp_min == 0) && (expr->exp_max == -1)) {
8000 rep[0] = '*';
8001 rep[1] = 0;
8002 } else if ((expr->exp_min == 1) && (expr->exp_max == -1)) {
8003 rep[0] = '+';
8004 rep[1] = 0;
8005 } else if (expr->exp_max == expr->exp_min) {
8006 snprintf(rep, 39, "{%d}", expr->exp_min);
8007 } else if (expr->exp_max < 0) {
8008 snprintf(rep, 39, "{%d,inf}", expr->exp_min);
8009 } else {
8010 snprintf(rep, 39, "{%d,%d}", expr->exp_min, expr->exp_max);
8011 }
8012 rep[39] = 0;
8013 xmlBufferWriteChar(buf, rep);
8014 break;
8015 }
8016 default:
8017 fprintf(stderr, "Error in tree\n");
8018 }
8019 if (glob)
8020 xmlBufferWriteChar(buf, ")");
8021 }
8022 /**
8023 * xmlExpDump:
8024 * @buf: a buffer to receive the output
8025 * @expr: the compiled expression
8026 *
8027 * Serialize the expression as compiled to the buffer
8028 */
8029 void
xmlExpDump(xmlBufferPtr buf,xmlExpNodePtr expr)8030 xmlExpDump(xmlBufferPtr buf, xmlExpNodePtr expr) {
8031 if ((buf == NULL) || (expr == NULL))
8032 return;
8033 xmlExpDumpInt(buf, expr, 0);
8034 }
8035
8036 /**
8037 * xmlExpMaxToken:
8038 * @expr: a compiled expression
8039 *
8040 * Indicate the maximum number of input a expression can accept
8041 *
8042 * Returns the maximum length or -1 in case of error
8043 */
8044 int
xmlExpMaxToken(xmlExpNodePtr expr)8045 xmlExpMaxToken(xmlExpNodePtr expr) {
8046 if (expr == NULL)
8047 return(-1);
8048 return(expr->c_max);
8049 }
8050
8051 /**
8052 * xmlExpCtxtNbNodes:
8053 * @ctxt: an expression context
8054 *
8055 * Debugging facility provides the number of allocated nodes at a that point
8056 *
8057 * Returns the number of nodes in use or -1 in case of error
8058 */
8059 int
xmlExpCtxtNbNodes(xmlExpCtxtPtr ctxt)8060 xmlExpCtxtNbNodes(xmlExpCtxtPtr ctxt) {
8061 if (ctxt == NULL)
8062 return(-1);
8063 return(ctxt->nb_nodes);
8064 }
8065
8066 /**
8067 * xmlExpCtxtNbCons:
8068 * @ctxt: an expression context
8069 *
8070 * Debugging facility provides the number of allocated nodes over lifetime
8071 *
8072 * Returns the number of nodes ever allocated or -1 in case of error
8073 */
8074 int
xmlExpCtxtNbCons(xmlExpCtxtPtr ctxt)8075 xmlExpCtxtNbCons(xmlExpCtxtPtr ctxt) {
8076 if (ctxt == NULL)
8077 return(-1);
8078 return(ctxt->nb_cons);
8079 }
8080
8081 #endif /* LIBXML_EXPR_ENABLED */
8082 #define bottom_xmlregexp
8083 #include "elfgcchack.h"
8084 #endif /* LIBXML_REGEXP_ENABLED */
8085