1 /*
2  * pattern.c: Implemetation of selectors for nodes
3  *
4  * Reference:
5  *   http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/
6  *   to some extent
7  *   http://www.w3.org/TR/1999/REC-xml-19991116
8  *
9  * See Copyright for the status of this software.
10  *
11  * daniel@veillard.com
12  */
13 
14 /*
15  * TODO:
16  * - compilation flags to check for specific syntaxes
17  *   using flags of xmlPatterncompile()
18  * - making clear how pattern starting with / or . need to be handled,
19  *   currently push(NULL, NULL) means a reset of the streaming context
20  *   and indicating we are on / (the document node), probably need
21  *   something similar for .
22  * - get rid of the "compile" starting with lowercase
23  * - DONE (2006-05-16): get rid of the Strdup/Strndup in case of dictionary
24  */
25 
26 #define IN_LIBXML
27 #include "libxml.h"
28 
29 #include <string.h>
30 #include <libxml/xmlmemory.h>
31 #include <libxml/tree.h>
32 #include <libxml/hash.h>
33 #include <libxml/dict.h>
34 #include <libxml/xmlerror.h>
35 #include <libxml/parserInternals.h>
36 #include <libxml/pattern.h>
37 
38 #ifdef LIBXML_PATTERN_ENABLED
39 
40 /* #define DEBUG_STREAMING */
41 
42 #ifdef ERROR
43 #undef ERROR
44 #endif
45 #define ERROR(a, b, c, d)
46 #define ERROR5(a, b, c, d, e)
47 
48 #define XML_STREAM_STEP_DESC	1
49 #define XML_STREAM_STEP_FINAL	2
50 #define XML_STREAM_STEP_ROOT	4
51 #define XML_STREAM_STEP_ATTR	8
52 #define XML_STREAM_STEP_NODE	16
53 #define XML_STREAM_STEP_IN_SET	32
54 
55 /*
56 * NOTE: Those private flags (XML_STREAM_xxx) are used
57 *   in _xmlStreamCtxt->flag. They extend the public
58 *   xmlPatternFlags, so be carefull not to interfere with the
59 *   reserved values for xmlPatternFlags.
60 */
61 #define XML_STREAM_FINAL_IS_ANY_NODE 1<<14
62 #define XML_STREAM_FROM_ROOT 1<<15
63 #define XML_STREAM_DESC 1<<16
64 
65 /*
66 * XML_STREAM_ANY_NODE is used for comparison against
67 * xmlElementType enums, to indicate a node of any type.
68 */
69 #define XML_STREAM_ANY_NODE 100
70 
71 #define XML_PATTERN_NOTPATTERN  (XML_PATTERN_XPATH | \
72 				 XML_PATTERN_XSSEL | \
73 				 XML_PATTERN_XSFIELD)
74 
75 #define XML_STREAM_XS_IDC(c) ((c)->flags & \
76     (XML_PATTERN_XSSEL | XML_PATTERN_XSFIELD))
77 
78 #define XML_STREAM_XS_IDC_SEL(c) ((c)->flags & XML_PATTERN_XSSEL)
79 
80 #define XML_STREAM_XS_IDC_FIELD(c) ((c)->flags & XML_PATTERN_XSFIELD)
81 
82 #define XML_PAT_COPY_NSNAME(c, r, nsname) \
83     if ((c)->comp->dict) \
84 	r = (xmlChar *) xmlDictLookup((c)->comp->dict, BAD_CAST nsname, -1); \
85     else r = xmlStrdup(BAD_CAST nsname);
86 
87 #define XML_PAT_FREE_STRING(c, r) if ((c)->comp->dict == NULL) xmlFree(r);
88 
89 typedef struct _xmlStreamStep xmlStreamStep;
90 typedef xmlStreamStep *xmlStreamStepPtr;
91 struct _xmlStreamStep {
92     int flags;			/* properties of that step */
93     const xmlChar *name;	/* first string value if NULL accept all */
94     const xmlChar *ns;		/* second string value */
95     int nodeType;		/* type of node */
96 };
97 
98 typedef struct _xmlStreamComp xmlStreamComp;
99 typedef xmlStreamComp *xmlStreamCompPtr;
100 struct _xmlStreamComp {
101     xmlDict *dict;		/* the dictionary if any */
102     int nbStep;			/* number of steps in the automata */
103     int maxStep;		/* allocated number of steps */
104     xmlStreamStepPtr steps;	/* the array of steps */
105     int flags;
106 };
107 
108 struct _xmlStreamCtxt {
109     struct _xmlStreamCtxt *next;/* link to next sub pattern if | */
110     xmlStreamCompPtr comp;	/* the compiled stream */
111     int nbState;		/* number of states in the automata */
112     int maxState;		/* allocated number of states */
113     int level;			/* how deep are we ? */
114     int *states;		/* the array of step indexes */
115     int flags;			/* validation options */
116     int blockLevel;
117 };
118 
119 static void xmlFreeStreamComp(xmlStreamCompPtr comp);
120 
121 /*
122  * Types are private:
123  */
124 
125 typedef enum {
126     XML_OP_END=0,
127     XML_OP_ROOT,
128     XML_OP_ELEM,
129     XML_OP_CHILD,
130     XML_OP_ATTR,
131     XML_OP_PARENT,
132     XML_OP_ANCESTOR,
133     XML_OP_NS,
134     XML_OP_ALL
135 } xmlPatOp;
136 
137 
138 typedef struct _xmlStepState xmlStepState;
139 typedef xmlStepState *xmlStepStatePtr;
140 struct _xmlStepState {
141     int step;
142     xmlNodePtr node;
143 };
144 
145 typedef struct _xmlStepStates xmlStepStates;
146 typedef xmlStepStates *xmlStepStatesPtr;
147 struct _xmlStepStates {
148     int nbstates;
149     int maxstates;
150     xmlStepStatePtr states;
151 };
152 
153 typedef struct _xmlStepOp xmlStepOp;
154 typedef xmlStepOp *xmlStepOpPtr;
155 struct _xmlStepOp {
156     xmlPatOp op;
157     const xmlChar *value;
158     const xmlChar *value2; /* The namespace name */
159 };
160 
161 #define PAT_FROM_ROOT	(1<<8)
162 #define PAT_FROM_CUR	(1<<9)
163 
164 struct _xmlPattern {
165     void *data;		/* the associated template */
166     xmlDictPtr dict;		/* the optional dictionary */
167     struct _xmlPattern *next;	/* next pattern if | is used */
168     const xmlChar *pattern;	/* the pattern */
169     int flags;			/* flags */
170     int nbStep;
171     int maxStep;
172     xmlStepOpPtr steps;        /* ops for computation */
173     xmlStreamCompPtr stream;	/* the streaming data if any */
174 };
175 
176 typedef struct _xmlPatParserContext xmlPatParserContext;
177 typedef xmlPatParserContext *xmlPatParserContextPtr;
178 struct _xmlPatParserContext {
179     const xmlChar *cur;			/* the current char being parsed */
180     const xmlChar *base;		/* the full expression */
181     int	           error;		/* error code */
182     xmlDictPtr     dict;		/* the dictionary if any */
183     xmlPatternPtr  comp;		/* the result */
184     xmlNodePtr     elem;		/* the current node if any */
185     const xmlChar **namespaces;		/* the namespaces definitions */
186     int   nb_namespaces;		/* the number of namespaces */
187 };
188 
189 /************************************************************************
190  *									*
191  *			Type functions					*
192  *									*
193  ************************************************************************/
194 
195 /**
196  * xmlNewPattern:
197  *
198  * Create a new XSLT Pattern
199  *
200  * Returns the newly allocated xmlPatternPtr or NULL in case of error
201  */
202 static xmlPatternPtr
xmlNewPattern(void)203 xmlNewPattern(void) {
204     xmlPatternPtr cur;
205 
206     cur = (xmlPatternPtr) xmlMalloc(sizeof(xmlPattern));
207     if (cur == NULL) {
208 	ERROR(NULL, NULL, NULL,
209 		"xmlNewPattern : malloc failed\n");
210 	return(NULL);
211     }
212     memset(cur, 0, sizeof(xmlPattern));
213     cur->maxStep = 10;
214     cur->steps = (xmlStepOpPtr) xmlMalloc(cur->maxStep * sizeof(xmlStepOp));
215     if (cur->steps == NULL) {
216         xmlFree(cur);
217 	ERROR(NULL, NULL, NULL,
218 		"xmlNewPattern : malloc failed\n");
219 	return(NULL);
220     }
221     return(cur);
222 }
223 
224 /**
225  * xmlFreePattern:
226  * @comp:  an XSLT comp
227  *
228  * Free up the memory allocated by @comp
229  */
230 void
xmlFreePattern(xmlPatternPtr comp)231 xmlFreePattern(xmlPatternPtr comp) {
232     xmlStepOpPtr op;
233     int i;
234 
235     if (comp == NULL)
236 	return;
237     if (comp->next != NULL)
238         xmlFreePattern(comp->next);
239     if (comp->stream != NULL)
240         xmlFreeStreamComp(comp->stream);
241     if (comp->pattern != NULL)
242 	xmlFree((xmlChar *)comp->pattern);
243     if (comp->steps != NULL) {
244         if (comp->dict == NULL) {
245 	    for (i = 0;i < comp->nbStep;i++) {
246 		op = &comp->steps[i];
247 		if (op->value != NULL)
248 		    xmlFree((xmlChar *) op->value);
249 		if (op->value2 != NULL)
250 		    xmlFree((xmlChar *) op->value2);
251 	    }
252 	}
253 	xmlFree(comp->steps);
254     }
255     if (comp->dict != NULL)
256         xmlDictFree(comp->dict);
257 
258     memset(comp, -1, sizeof(xmlPattern));
259     xmlFree(comp);
260 }
261 
262 /**
263  * xmlFreePatternList:
264  * @comp:  an XSLT comp list
265  *
266  * Free up the memory allocated by all the elements of @comp
267  */
268 void
xmlFreePatternList(xmlPatternPtr comp)269 xmlFreePatternList(xmlPatternPtr comp) {
270     xmlPatternPtr cur;
271 
272     while (comp != NULL) {
273 	cur = comp;
274 	comp = comp->next;
275 	cur->next = NULL;
276 	xmlFreePattern(cur);
277     }
278 }
279 
280 /**
281  * xmlNewPatParserContext:
282  * @pattern:  the pattern context
283  * @dict:  the inherited dictionary or NULL
284  * @namespaces: the prefix definitions, array of [URI, prefix] terminated
285  *              with [NULL, NULL] or NULL if no namespace is used
286  *
287  * Create a new XML pattern parser context
288  *
289  * Returns the newly allocated xmlPatParserContextPtr or NULL in case of error
290  */
291 static xmlPatParserContextPtr
xmlNewPatParserContext(const xmlChar * pattern,xmlDictPtr dict,const xmlChar ** namespaces)292 xmlNewPatParserContext(const xmlChar *pattern, xmlDictPtr dict,
293                        const xmlChar **namespaces) {
294     xmlPatParserContextPtr cur;
295 
296     if (pattern == NULL)
297         return(NULL);
298 
299     cur = (xmlPatParserContextPtr) xmlMalloc(sizeof(xmlPatParserContext));
300     if (cur == NULL) {
301 	ERROR(NULL, NULL, NULL,
302 		"xmlNewPatParserContext : malloc failed\n");
303 	return(NULL);
304     }
305     memset(cur, 0, sizeof(xmlPatParserContext));
306     cur->dict = dict;
307     cur->cur = pattern;
308     cur->base = pattern;
309     if (namespaces != NULL) {
310         int i;
311         for (i = 0;namespaces[2 * i] != NULL;i++)
312             ;
313         cur->nb_namespaces = i;
314     } else {
315         cur->nb_namespaces = 0;
316     }
317     cur->namespaces = namespaces;
318     return(cur);
319 }
320 
321 /**
322  * xmlFreePatParserContext:
323  * @ctxt:  an XSLT parser context
324  *
325  * Free up the memory allocated by @ctxt
326  */
327 static void
xmlFreePatParserContext(xmlPatParserContextPtr ctxt)328 xmlFreePatParserContext(xmlPatParserContextPtr ctxt) {
329     if (ctxt == NULL)
330 	return;
331     memset(ctxt, -1, sizeof(xmlPatParserContext));
332     xmlFree(ctxt);
333 }
334 
335 /**
336  * xmlPatternAdd:
337  * @comp:  the compiled match expression
338  * @op:  an op
339  * @value:  the first value
340  * @value2:  the second value
341  *
342  * Add a step to an XSLT Compiled Match
343  *
344  * Returns -1 in case of failure, 0 otherwise.
345  */
346 static int
xmlPatternAdd(xmlPatParserContextPtr ctxt ATTRIBUTE_UNUSED,xmlPatternPtr comp,xmlPatOp op,xmlChar * value,xmlChar * value2)347 xmlPatternAdd(xmlPatParserContextPtr ctxt ATTRIBUTE_UNUSED,
348                 xmlPatternPtr comp,
349                 xmlPatOp op, xmlChar * value, xmlChar * value2)
350 {
351     if (comp->nbStep >= comp->maxStep) {
352         xmlStepOpPtr temp;
353 	temp = (xmlStepOpPtr) xmlRealloc(comp->steps, comp->maxStep * 2 *
354 	                                 sizeof(xmlStepOp));
355         if (temp == NULL) {
356 	    ERROR(ctxt, NULL, NULL,
357 			     "xmlPatternAdd: realloc failed\n");
358 	    return (-1);
359 	}
360 	comp->steps = temp;
361 	comp->maxStep *= 2;
362     }
363     comp->steps[comp->nbStep].op = op;
364     comp->steps[comp->nbStep].value = value;
365     comp->steps[comp->nbStep].value2 = value2;
366     comp->nbStep++;
367     return (0);
368 }
369 
370 #if 0
371 /**
372  * xsltSwapTopPattern:
373  * @comp:  the compiled match expression
374  *
375  * reverse the two top steps.
376  */
377 static void
378 xsltSwapTopPattern(xmlPatternPtr comp) {
379     int i;
380     int j = comp->nbStep - 1;
381 
382     if (j > 0) {
383 	register const xmlChar *tmp;
384 	register xmlPatOp op;
385 	i = j - 1;
386 	tmp = comp->steps[i].value;
387 	comp->steps[i].value = comp->steps[j].value;
388 	comp->steps[j].value = tmp;
389 	tmp = comp->steps[i].value2;
390 	comp->steps[i].value2 = comp->steps[j].value2;
391 	comp->steps[j].value2 = tmp;
392 	op = comp->steps[i].op;
393 	comp->steps[i].op = comp->steps[j].op;
394 	comp->steps[j].op = op;
395     }
396 }
397 #endif
398 
399 /**
400  * xmlReversePattern:
401  * @comp:  the compiled match expression
402  *
403  * reverse all the stack of expressions
404  *
405  * returns 0 in case of success and -1 in case of error.
406  */
407 static int
xmlReversePattern(xmlPatternPtr comp)408 xmlReversePattern(xmlPatternPtr comp) {
409     int i, j;
410 
411     /*
412      * remove the leading // for //a or .//a
413      */
414     if ((comp->nbStep > 0) && (comp->steps[0].op == XML_OP_ANCESTOR)) {
415         for (i = 0, j = 1;j < comp->nbStep;i++,j++) {
416 	    comp->steps[i].value = comp->steps[j].value;
417 	    comp->steps[i].value2 = comp->steps[j].value2;
418 	    comp->steps[i].op = comp->steps[j].op;
419 	}
420 	comp->nbStep--;
421     }
422     if (comp->nbStep >= comp->maxStep) {
423         xmlStepOpPtr temp;
424 	temp = (xmlStepOpPtr) xmlRealloc(comp->steps, comp->maxStep * 2 *
425 	                                 sizeof(xmlStepOp));
426         if (temp == NULL) {
427 	    ERROR(ctxt, NULL, NULL,
428 			     "xmlReversePattern: realloc failed\n");
429 	    return (-1);
430 	}
431 	comp->steps = temp;
432 	comp->maxStep *= 2;
433     }
434     i = 0;
435     j = comp->nbStep - 1;
436     while (j > i) {
437 	register const xmlChar *tmp;
438 	register xmlPatOp op;
439 	tmp = comp->steps[i].value;
440 	comp->steps[i].value = comp->steps[j].value;
441 	comp->steps[j].value = tmp;
442 	tmp = comp->steps[i].value2;
443 	comp->steps[i].value2 = comp->steps[j].value2;
444 	comp->steps[j].value2 = tmp;
445 	op = comp->steps[i].op;
446 	comp->steps[i].op = comp->steps[j].op;
447 	comp->steps[j].op = op;
448 	j--;
449 	i++;
450     }
451     comp->steps[comp->nbStep].value = NULL;
452     comp->steps[comp->nbStep].value2 = NULL;
453     comp->steps[comp->nbStep++].op = XML_OP_END;
454     return(0);
455 }
456 
457 /************************************************************************
458  *									*
459  *		The interpreter for the precompiled patterns		*
460  *									*
461  ************************************************************************/
462 
463 static int
xmlPatPushState(xmlStepStates * states,int step,xmlNodePtr node)464 xmlPatPushState(xmlStepStates *states, int step, xmlNodePtr node) {
465     if ((states->states == NULL) || (states->maxstates <= 0)) {
466         states->maxstates = 4;
467 	states->nbstates = 0;
468 	states->states = xmlMalloc(4 * sizeof(xmlStepState));
469     }
470     else if (states->maxstates <= states->nbstates) {
471         xmlStepState *tmp;
472 
473 	tmp = (xmlStepStatePtr) xmlRealloc(states->states,
474 			       2 * states->maxstates * sizeof(xmlStepState));
475 	if (tmp == NULL)
476 	    return(-1);
477 	states->states = tmp;
478 	states->maxstates *= 2;
479     }
480     states->states[states->nbstates].step = step;
481     states->states[states->nbstates++].node = node;
482 #if 0
483     fprintf(stderr, "Push: %d, %s\n", step, node->name);
484 #endif
485     return(0);
486 }
487 
488 /**
489  * xmlPatMatch:
490  * @comp: the precompiled pattern
491  * @node: a node
492  *
493  * Test whether the node matches the pattern
494  *
495  * Returns 1 if it matches, 0 if it doesn't and -1 in case of failure
496  */
497 static int
xmlPatMatch(xmlPatternPtr comp,xmlNodePtr node)498 xmlPatMatch(xmlPatternPtr comp, xmlNodePtr node) {
499     int i;
500     xmlStepOpPtr step;
501     xmlStepStates states = {0, 0, NULL}; /* // may require backtrack */
502 
503     if ((comp == NULL) || (node == NULL)) return(-1);
504     i = 0;
505 restart:
506     for (;i < comp->nbStep;i++) {
507 	step = &comp->steps[i];
508 	switch (step->op) {
509             case XML_OP_END:
510 		goto found;
511             case XML_OP_ROOT:
512 		if (node->type == XML_NAMESPACE_DECL)
513 		    goto rollback;
514 		node = node->parent;
515 		if ((node->type == XML_DOCUMENT_NODE) ||
516 #ifdef LIBXML_DOCB_ENABLED
517 		    (node->type == XML_DOCB_DOCUMENT_NODE) ||
518 #endif
519 		    (node->type == XML_HTML_DOCUMENT_NODE))
520 		    continue;
521 		goto rollback;
522             case XML_OP_ELEM:
523 		if (node->type != XML_ELEMENT_NODE)
524 		    goto rollback;
525 		if (step->value == NULL)
526 		    continue;
527 		if (step->value[0] != node->name[0])
528 		    goto rollback;
529 		if (!xmlStrEqual(step->value, node->name))
530 		    goto rollback;
531 
532 		/* Namespace test */
533 		if (node->ns == NULL) {
534 		    if (step->value2 != NULL)
535 			goto rollback;
536 		} else if (node->ns->href != NULL) {
537 		    if (step->value2 == NULL)
538 			goto rollback;
539 		    if (!xmlStrEqual(step->value2, node->ns->href))
540 			goto rollback;
541 		}
542 		continue;
543             case XML_OP_CHILD: {
544 		xmlNodePtr lst;
545 
546 		if ((node->type != XML_ELEMENT_NODE) &&
547 		    (node->type != XML_DOCUMENT_NODE) &&
548 #ifdef LIBXML_DOCB_ENABLED
549 		    (node->type != XML_DOCB_DOCUMENT_NODE) &&
550 #endif
551 		    (node->type != XML_HTML_DOCUMENT_NODE))
552 		    goto rollback;
553 
554 		lst = node->children;
555 
556 		if (step->value != NULL) {
557 		    while (lst != NULL) {
558 			if ((lst->type == XML_ELEMENT_NODE) &&
559 			    (step->value[0] == lst->name[0]) &&
560 			    (xmlStrEqual(step->value, lst->name)))
561 			    break;
562 			lst = lst->next;
563 		    }
564 		    if (lst != NULL)
565 			continue;
566 		}
567 		goto rollback;
568 	    }
569             case XML_OP_ATTR:
570 		if (node->type != XML_ATTRIBUTE_NODE)
571 		    goto rollback;
572 		if (step->value != NULL) {
573 		    if (step->value[0] != node->name[0])
574 			goto rollback;
575 		    if (!xmlStrEqual(step->value, node->name))
576 			goto rollback;
577 		}
578 		/* Namespace test */
579 		if (node->ns == NULL) {
580 		    if (step->value2 != NULL)
581 			goto rollback;
582 		} else if (step->value2 != NULL) {
583 		    if (!xmlStrEqual(step->value2, node->ns->href))
584 			goto rollback;
585 		}
586 		continue;
587             case XML_OP_PARENT:
588 		if ((node->type == XML_DOCUMENT_NODE) ||
589 		    (node->type == XML_HTML_DOCUMENT_NODE) ||
590 #ifdef LIBXML_DOCB_ENABLED
591 		    (node->type == XML_DOCB_DOCUMENT_NODE) ||
592 #endif
593 		    (node->type == XML_NAMESPACE_DECL))
594 		    goto rollback;
595 		node = node->parent;
596 		if (node == NULL)
597 		    goto rollback;
598 		if (step->value == NULL)
599 		    continue;
600 		if (step->value[0] != node->name[0])
601 		    goto rollback;
602 		if (!xmlStrEqual(step->value, node->name))
603 		    goto rollback;
604 		/* Namespace test */
605 		if (node->ns == NULL) {
606 		    if (step->value2 != NULL)
607 			goto rollback;
608 		} else if (node->ns->href != NULL) {
609 		    if (step->value2 == NULL)
610 			goto rollback;
611 		    if (!xmlStrEqual(step->value2, node->ns->href))
612 			goto rollback;
613 		}
614 		continue;
615             case XML_OP_ANCESTOR:
616 		/* TODO: implement coalescing of ANCESTOR/NODE ops */
617 		if (step->value == NULL) {
618 		    i++;
619 		    step = &comp->steps[i];
620 		    if (step->op == XML_OP_ROOT)
621 			goto found;
622 		    if (step->op != XML_OP_ELEM)
623 			goto rollback;
624 		    if (step->value == NULL)
625 			return(-1);
626 		}
627 		if (node == NULL)
628 		    goto rollback;
629 		if ((node->type == XML_DOCUMENT_NODE) ||
630 		    (node->type == XML_HTML_DOCUMENT_NODE) ||
631 #ifdef LIBXML_DOCB_ENABLED
632 		    (node->type == XML_DOCB_DOCUMENT_NODE) ||
633 #endif
634 		    (node->type == XML_NAMESPACE_DECL))
635 		    goto rollback;
636 		node = node->parent;
637 		while (node != NULL) {
638 		    if ((node->type == XML_ELEMENT_NODE) &&
639 			(step->value[0] == node->name[0]) &&
640 			(xmlStrEqual(step->value, node->name))) {
641 			/* Namespace test */
642 			if (node->ns == NULL) {
643 			    if (step->value2 == NULL)
644 				break;
645 			} else if (node->ns->href != NULL) {
646 			    if ((step->value2 != NULL) &&
647 			        (xmlStrEqual(step->value2, node->ns->href)))
648 				break;
649 			}
650 		    }
651 		    node = node->parent;
652 		}
653 		if (node == NULL)
654 		    goto rollback;
655 		/*
656 		 * prepare a potential rollback from here
657 		 * for ancestors of that node.
658 		 */
659 		if (step->op == XML_OP_ANCESTOR)
660 		    xmlPatPushState(&states, i, node);
661 		else
662 		    xmlPatPushState(&states, i - 1, node);
663 		continue;
664             case XML_OP_NS:
665 		if (node->type != XML_ELEMENT_NODE)
666 		    goto rollback;
667 		if (node->ns == NULL) {
668 		    if (step->value != NULL)
669 			goto rollback;
670 		} else if (node->ns->href != NULL) {
671 		    if (step->value == NULL)
672 			goto rollback;
673 		    if (!xmlStrEqual(step->value, node->ns->href))
674 			goto rollback;
675 		}
676 		break;
677             case XML_OP_ALL:
678 		if (node->type != XML_ELEMENT_NODE)
679 		    goto rollback;
680 		break;
681 	}
682     }
683 found:
684     if (states.states != NULL) {
685         /* Free the rollback states */
686 	xmlFree(states.states);
687     }
688     return(1);
689 rollback:
690     /* got an error try to rollback */
691     if (states.states == NULL)
692 	return(0);
693     if (states.nbstates <= 0) {
694 	xmlFree(states.states);
695 	return(0);
696     }
697     states.nbstates--;
698     i = states.states[states.nbstates].step;
699     node = states.states[states.nbstates].node;
700 #if 0
701     fprintf(stderr, "Pop: %d, %s\n", i, node->name);
702 #endif
703     goto restart;
704 }
705 
706 /************************************************************************
707  *									*
708  *			Dedicated parser for templates			*
709  *									*
710  ************************************************************************/
711 
712 #define TODO								\
713     xmlGenericError(xmlGenericErrorContext,				\
714 	    "Unimplemented block at %s:%d\n",				\
715             __FILE__, __LINE__);
716 #define CUR (*ctxt->cur)
717 #define SKIP(val) ctxt->cur += (val)
718 #define NXT(val) ctxt->cur[(val)]
719 #define PEEKPREV(val) ctxt->cur[-(val)]
720 #define CUR_PTR ctxt->cur
721 
722 #define SKIP_BLANKS							\
723     while (IS_BLANK_CH(CUR)) NEXT
724 
725 #define CURRENT (*ctxt->cur)
726 #define NEXT ((*ctxt->cur) ?  ctxt->cur++: ctxt->cur)
727 
728 
729 #define PUSH(op, val, val2)						\
730     if (xmlPatternAdd(ctxt, ctxt->comp, (op), (val), (val2))) goto error;
731 
732 #define XSLT_ERROR(X)							\
733     { xsltError(ctxt, __FILE__, __LINE__, X);				\
734       ctxt->error = (X); return; }
735 
736 #define XSLT_ERROR0(X)							\
737     { xsltError(ctxt, __FILE__, __LINE__, X);				\
738       ctxt->error = (X); return(0); }
739 
740 #if 0
741 /**
742  * xmlPatScanLiteral:
743  * @ctxt:  the XPath Parser context
744  *
745  * Parse an XPath Litteral:
746  *
747  * [29] Literal ::= '"' [^"]* '"'
748  *                | "'" [^']* "'"
749  *
750  * Returns the Literal parsed or NULL
751  */
752 
753 static xmlChar *
754 xmlPatScanLiteral(xmlPatParserContextPtr ctxt) {
755     const xmlChar *q, *cur;
756     xmlChar *ret = NULL;
757     int val, len;
758 
759     SKIP_BLANKS;
760     if (CUR == '"') {
761         NEXT;
762 	cur = q = CUR_PTR;
763 	val = xmlStringCurrentChar(NULL, cur, &len);
764 	while ((IS_CHAR(val)) && (val != '"')) {
765 	    cur += len;
766 	    val = xmlStringCurrentChar(NULL, cur, &len);
767 	}
768 	if (!IS_CHAR(val)) {
769 	    ctxt->error = 1;
770 	    return(NULL);
771 	} else {
772 	    if (ctxt->dict)
773 		ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
774 	    else
775 		ret = xmlStrndup(q, cur - q);
776         }
777 	cur += len;
778 	CUR_PTR = cur;
779     } else if (CUR == '\'') {
780         NEXT;
781 	cur = q = CUR_PTR;
782 	val = xmlStringCurrentChar(NULL, cur, &len);
783 	while ((IS_CHAR(val)) && (val != '\'')) {
784 	    cur += len;
785 	    val = xmlStringCurrentChar(NULL, cur, &len);
786 	}
787 	if (!IS_CHAR(val)) {
788 	    ctxt->error = 1;
789 	    return(NULL);
790 	} else {
791 	    if (ctxt->dict)
792 		ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
793 	    else
794 		ret = xmlStrndup(q, cur - q);
795         }
796 	cur += len;
797 	CUR_PTR = cur;
798     } else {
799 	/* XP_ERROR(XPATH_START_LITERAL_ERROR); */
800 	ctxt->error = 1;
801 	return(NULL);
802     }
803     return(ret);
804 }
805 #endif
806 
807 /**
808  * xmlPatScanName:
809  * @ctxt:  the XPath Parser context
810  *
811  * [4] NameChar ::= Letter | Digit | '.' | '-' | '_' |
812  *                  CombiningChar | Extender
813  *
814  * [5] Name ::= (Letter | '_' | ':') (NameChar)*
815  *
816  * [6] Names ::= Name (S Name)*
817  *
818  * Returns the Name parsed or NULL
819  */
820 
821 static xmlChar *
xmlPatScanName(xmlPatParserContextPtr ctxt)822 xmlPatScanName(xmlPatParserContextPtr ctxt) {
823     const xmlChar *q, *cur;
824     xmlChar *ret = NULL;
825     int val, len;
826 
827     SKIP_BLANKS;
828 
829     cur = q = CUR_PTR;
830     val = xmlStringCurrentChar(NULL, cur, &len);
831     if (!IS_LETTER(val) && (val != '_') && (val != ':'))
832 	return(NULL);
833 
834     while ((IS_LETTER(val)) || (IS_DIGIT(val)) ||
835            (val == '.') || (val == '-') ||
836 	   (val == '_') ||
837 	   (IS_COMBINING(val)) ||
838 	   (IS_EXTENDER(val))) {
839 	cur += len;
840 	val = xmlStringCurrentChar(NULL, cur, &len);
841     }
842     if (ctxt->dict)
843 	ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
844     else
845 	ret = xmlStrndup(q, cur - q);
846     CUR_PTR = cur;
847     return(ret);
848 }
849 
850 /**
851  * xmlPatScanNCName:
852  * @ctxt:  the XPath Parser context
853  *
854  * Parses a non qualified name
855  *
856  * Returns the Name parsed or NULL
857  */
858 
859 static xmlChar *
xmlPatScanNCName(xmlPatParserContextPtr ctxt)860 xmlPatScanNCName(xmlPatParserContextPtr ctxt) {
861     const xmlChar *q, *cur;
862     xmlChar *ret = NULL;
863     int val, len;
864 
865     SKIP_BLANKS;
866 
867     cur = q = CUR_PTR;
868     val = xmlStringCurrentChar(NULL, cur, &len);
869     if (!IS_LETTER(val) && (val != '_'))
870 	return(NULL);
871 
872     while ((IS_LETTER(val)) || (IS_DIGIT(val)) ||
873            (val == '.') || (val == '-') ||
874 	   (val == '_') ||
875 	   (IS_COMBINING(val)) ||
876 	   (IS_EXTENDER(val))) {
877 	cur += len;
878 	val = xmlStringCurrentChar(NULL, cur, &len);
879     }
880     if (ctxt->dict)
881 	ret = (xmlChar *) xmlDictLookup(ctxt->dict, q, cur - q);
882     else
883 	ret = xmlStrndup(q, cur - q);
884     CUR_PTR = cur;
885     return(ret);
886 }
887 
888 #if 0
889 /**
890  * xmlPatScanQName:
891  * @ctxt:  the XPath Parser context
892  * @prefix:  the place to store the prefix
893  *
894  * Parse a qualified name
895  *
896  * Returns the Name parsed or NULL
897  */
898 
899 static xmlChar *
900 xmlPatScanQName(xmlPatParserContextPtr ctxt, xmlChar **prefix) {
901     xmlChar *ret = NULL;
902 
903     *prefix = NULL;
904     ret = xmlPatScanNCName(ctxt);
905     if (CUR == ':') {
906         *prefix = ret;
907 	NEXT;
908 	ret = xmlPatScanNCName(ctxt);
909     }
910     return(ret);
911 }
912 #endif
913 
914 /**
915  * xmlCompileAttributeTest:
916  * @ctxt:  the compilation context
917  *
918  * Compile an attribute test.
919  */
920 static void
xmlCompileAttributeTest(xmlPatParserContextPtr ctxt)921 xmlCompileAttributeTest(xmlPatParserContextPtr ctxt) {
922     xmlChar *token = NULL;
923     xmlChar *name = NULL;
924     xmlChar *URL = NULL;
925 
926     SKIP_BLANKS;
927     name = xmlPatScanNCName(ctxt);
928     if (name == NULL) {
929 	if (CUR == '*') {
930 	    PUSH(XML_OP_ATTR, NULL, NULL);
931 	    NEXT;
932 	} else {
933 	    ERROR(NULL, NULL, NULL,
934 		"xmlCompileAttributeTest : Name expected\n");
935 	    ctxt->error = 1;
936 	}
937 	return;
938     }
939     if (CUR == ':') {
940 	int i;
941 	xmlChar *prefix = name;
942 
943 	NEXT;
944 
945 	if (IS_BLANK_CH(CUR)) {
946 	    ERROR5(NULL, NULL, NULL, "Invalid QName.\n", NULL);
947 	    XML_PAT_FREE_STRING(ctxt, prefix);
948 	    ctxt->error = 1;
949 	    goto error;
950 	}
951 	/*
952 	* This is a namespace match
953 	*/
954 	token = xmlPatScanName(ctxt);
955 	if ((prefix[0] == 'x') &&
956 	    (prefix[1] == 'm') &&
957 	    (prefix[2] == 'l') &&
958 	    (prefix[3] == 0))
959 	{
960 	    XML_PAT_COPY_NSNAME(ctxt, URL, XML_XML_NAMESPACE);
961 	} else {
962 	    for (i = 0;i < ctxt->nb_namespaces;i++) {
963 		if (xmlStrEqual(ctxt->namespaces[2 * i + 1], prefix)) {
964 		    XML_PAT_COPY_NSNAME(ctxt, URL, ctxt->namespaces[2 * i])
965 		    break;
966 		}
967 	    }
968 	    if (i >= ctxt->nb_namespaces) {
969 		ERROR5(NULL, NULL, NULL,
970 		    "xmlCompileAttributeTest : no namespace bound to prefix %s\n",
971 		    prefix);
972 		ctxt->error = 1;
973 		goto error;
974 	    }
975 	}
976 	XML_PAT_FREE_STRING(ctxt, prefix);
977 	if (token == NULL) {
978 	    if (CUR == '*') {
979 		NEXT;
980 		PUSH(XML_OP_ATTR, NULL, URL);
981 	    } else {
982 		ERROR(NULL, NULL, NULL,
983 		    "xmlCompileAttributeTest : Name expected\n");
984 		ctxt->error = 1;
985 		goto error;
986 	    }
987 	} else {
988 	    PUSH(XML_OP_ATTR, token, URL);
989 	}
990     } else {
991 	PUSH(XML_OP_ATTR, name, NULL);
992     }
993     return;
994 error:
995     if (URL != NULL)
996 	XML_PAT_FREE_STRING(ctxt, URL)
997     if (token != NULL)
998 	XML_PAT_FREE_STRING(ctxt, token);
999 }
1000 
1001 /**
1002  * xmlCompileStepPattern:
1003  * @ctxt:  the compilation context
1004  *
1005  * Compile the Step Pattern and generates a precompiled
1006  * form suitable for fast matching.
1007  *
1008  * [3]    Step    ::=    '.' | NameTest
1009  * [4]    NameTest    ::=    QName | '*' | NCName ':' '*'
1010  */
1011 
1012 static void
xmlCompileStepPattern(xmlPatParserContextPtr ctxt)1013 xmlCompileStepPattern(xmlPatParserContextPtr ctxt) {
1014     xmlChar *token = NULL;
1015     xmlChar *name = NULL;
1016     xmlChar *URL = NULL;
1017     int hasBlanks = 0;
1018 
1019     SKIP_BLANKS;
1020     if (CUR == '.') {
1021 	/*
1022 	* Context node.
1023 	*/
1024 	NEXT;
1025 	PUSH(XML_OP_ELEM, NULL, NULL);
1026 	return;
1027     }
1028     if (CUR == '@') {
1029 	/*
1030 	* Attribute test.
1031 	*/
1032 	if (XML_STREAM_XS_IDC_SEL(ctxt->comp)) {
1033 	    ERROR5(NULL, NULL, NULL,
1034 		"Unexpected attribute axis in '%s'.\n", ctxt->base);
1035 	    ctxt->error = 1;
1036 	    return;
1037 	}
1038 	NEXT;
1039 	xmlCompileAttributeTest(ctxt);
1040 	if (ctxt->error != 0)
1041 	    goto error;
1042 	return;
1043     }
1044     name = xmlPatScanNCName(ctxt);
1045     if (name == NULL) {
1046 	if (CUR == '*') {
1047 	    NEXT;
1048 	    PUSH(XML_OP_ALL, NULL, NULL);
1049 	    return;
1050 	} else {
1051 	    ERROR(NULL, NULL, NULL,
1052 		    "xmlCompileStepPattern : Name expected\n");
1053 	    ctxt->error = 1;
1054 	    return;
1055 	}
1056     }
1057     if (IS_BLANK_CH(CUR)) {
1058 	hasBlanks = 1;
1059 	SKIP_BLANKS;
1060     }
1061     if (CUR == ':') {
1062 	NEXT;
1063 	if (CUR != ':') {
1064 	    xmlChar *prefix = name;
1065 	    int i;
1066 
1067 	    if (hasBlanks || IS_BLANK_CH(CUR)) {
1068 		ERROR5(NULL, NULL, NULL, "Invalid QName.\n", NULL);
1069 		ctxt->error = 1;
1070 		goto error;
1071 	    }
1072 	    /*
1073 	     * This is a namespace match
1074 	     */
1075 	    token = xmlPatScanName(ctxt);
1076 	    if ((prefix[0] == 'x') &&
1077 		(prefix[1] == 'm') &&
1078 		(prefix[2] == 'l') &&
1079 		(prefix[3] == 0))
1080 	    {
1081 		XML_PAT_COPY_NSNAME(ctxt, URL, XML_XML_NAMESPACE)
1082 	    } else {
1083 		for (i = 0;i < ctxt->nb_namespaces;i++) {
1084 		    if (xmlStrEqual(ctxt->namespaces[2 * i + 1], prefix)) {
1085 			XML_PAT_COPY_NSNAME(ctxt, URL, ctxt->namespaces[2 * i])
1086 			break;
1087 		    }
1088 		}
1089 		if (i >= ctxt->nb_namespaces) {
1090 		    ERROR5(NULL, NULL, NULL,
1091 			"xmlCompileStepPattern : no namespace bound to prefix %s\n",
1092 			prefix);
1093 		    ctxt->error = 1;
1094 		    goto error;
1095 		}
1096 	    }
1097 	    XML_PAT_FREE_STRING(ctxt, prefix);
1098 	    name = NULL;
1099 	    if (token == NULL) {
1100 		if (CUR == '*') {
1101 		    NEXT;
1102 		    PUSH(XML_OP_NS, URL, NULL);
1103 		} else {
1104 		    ERROR(NULL, NULL, NULL,
1105 			    "xmlCompileStepPattern : Name expected\n");
1106 		    ctxt->error = 1;
1107 		    goto error;
1108 		}
1109 	    } else {
1110 		PUSH(XML_OP_ELEM, token, URL);
1111 	    }
1112 	} else {
1113 	    NEXT;
1114 	    if (xmlStrEqual(name, (const xmlChar *) "child")) {
1115 		XML_PAT_FREE_STRING(ctxt, name);
1116 		name = xmlPatScanName(ctxt);
1117 		if (name == NULL) {
1118 		    if (CUR == '*') {
1119 			NEXT;
1120 			PUSH(XML_OP_ALL, NULL, NULL);
1121 			return;
1122 		    } else {
1123 			ERROR(NULL, NULL, NULL,
1124 			    "xmlCompileStepPattern : QName expected\n");
1125 			ctxt->error = 1;
1126 			goto error;
1127 		    }
1128 		}
1129 		if (CUR == ':') {
1130 		    xmlChar *prefix = name;
1131 		    int i;
1132 
1133 		    NEXT;
1134 		    if (IS_BLANK_CH(CUR)) {
1135 			ERROR5(NULL, NULL, NULL, "Invalid QName.\n", NULL);
1136 			ctxt->error = 1;
1137 			goto error;
1138 		    }
1139 		    /*
1140 		    * This is a namespace match
1141 		    */
1142 		    token = xmlPatScanName(ctxt);
1143 		    if ((prefix[0] == 'x') &&
1144 			(prefix[1] == 'm') &&
1145 			(prefix[2] == 'l') &&
1146 			(prefix[3] == 0))
1147 		    {
1148 			XML_PAT_COPY_NSNAME(ctxt, URL, XML_XML_NAMESPACE)
1149 		    } else {
1150 			for (i = 0;i < ctxt->nb_namespaces;i++) {
1151 			    if (xmlStrEqual(ctxt->namespaces[2 * i + 1], prefix)) {
1152 				XML_PAT_COPY_NSNAME(ctxt, URL, ctxt->namespaces[2 * i])
1153 				break;
1154 			    }
1155 			}
1156 			if (i >= ctxt->nb_namespaces) {
1157 			    ERROR5(NULL, NULL, NULL,
1158 				"xmlCompileStepPattern : no namespace bound "
1159 				"to prefix %s\n", prefix);
1160 			    ctxt->error = 1;
1161 			    goto error;
1162 			}
1163 		    }
1164 		    XML_PAT_FREE_STRING(ctxt, prefix);
1165 		    name = NULL;
1166 		    if (token == NULL) {
1167 			if (CUR == '*') {
1168 			    NEXT;
1169 			    PUSH(XML_OP_NS, URL, NULL);
1170 			} else {
1171 			    ERROR(NULL, NULL, NULL,
1172 				"xmlCompileStepPattern : Name expected\n");
1173 			    ctxt->error = 1;
1174 			    goto error;
1175 			}
1176 		    } else {
1177 			PUSH(XML_OP_CHILD, token, URL);
1178 		    }
1179 		} else
1180 		    PUSH(XML_OP_CHILD, name, NULL);
1181 		return;
1182 	    } else if (xmlStrEqual(name, (const xmlChar *) "attribute")) {
1183 		XML_PAT_FREE_STRING(ctxt, name)
1184 		name = NULL;
1185 		if (XML_STREAM_XS_IDC_SEL(ctxt->comp)) {
1186 		    ERROR5(NULL, NULL, NULL,
1187 			"Unexpected attribute axis in '%s'.\n", ctxt->base);
1188 		    ctxt->error = 1;
1189 		    goto error;
1190 		}
1191 		xmlCompileAttributeTest(ctxt);
1192 		if (ctxt->error != 0)
1193 		    goto error;
1194 		return;
1195 	    } else {
1196 		ERROR5(NULL, NULL, NULL,
1197 		    "The 'element' or 'attribute' axis is expected.\n", NULL);
1198 		ctxt->error = 1;
1199 		goto error;
1200 	    }
1201 	}
1202     } else if (CUR == '*') {
1203         if (name != NULL) {
1204 	    ctxt->error = 1;
1205 	    goto error;
1206 	}
1207 	NEXT;
1208 	PUSH(XML_OP_ALL, token, NULL);
1209     } else {
1210 	PUSH(XML_OP_ELEM, name, NULL);
1211     }
1212     return;
1213 error:
1214     if (URL != NULL)
1215 	XML_PAT_FREE_STRING(ctxt, URL)
1216     if (token != NULL)
1217 	XML_PAT_FREE_STRING(ctxt, token)
1218     if (name != NULL)
1219 	XML_PAT_FREE_STRING(ctxt, name)
1220 }
1221 
1222 /**
1223  * xmlCompilePathPattern:
1224  * @ctxt:  the compilation context
1225  *
1226  * Compile the Path Pattern and generates a precompiled
1227  * form suitable for fast matching.
1228  *
1229  * [5]    Path    ::=    ('.//')? ( Step '/' )* ( Step | '@' NameTest )
1230  */
1231 static void
xmlCompilePathPattern(xmlPatParserContextPtr ctxt)1232 xmlCompilePathPattern(xmlPatParserContextPtr ctxt) {
1233     SKIP_BLANKS;
1234     if (CUR == '/') {
1235         ctxt->comp->flags |= PAT_FROM_ROOT;
1236     } else if ((CUR == '.') || (ctxt->comp->flags & XML_PATTERN_NOTPATTERN)) {
1237         ctxt->comp->flags |= PAT_FROM_CUR;
1238     }
1239 
1240     if ((CUR == '/') && (NXT(1) == '/')) {
1241 	PUSH(XML_OP_ANCESTOR, NULL, NULL);
1242 	NEXT;
1243 	NEXT;
1244     } else if ((CUR == '.') && (NXT(1) == '/') && (NXT(2) == '/')) {
1245 	PUSH(XML_OP_ANCESTOR, NULL, NULL);
1246 	NEXT;
1247 	NEXT;
1248 	NEXT;
1249 	/* Check for incompleteness. */
1250 	SKIP_BLANKS;
1251 	if (CUR == 0) {
1252 	    ERROR5(NULL, NULL, NULL,
1253 	       "Incomplete expression '%s'.\n", ctxt->base);
1254 	    ctxt->error = 1;
1255 	    goto error;
1256 	}
1257     }
1258     if (CUR == '@') {
1259 	NEXT;
1260 	xmlCompileAttributeTest(ctxt);
1261 	SKIP_BLANKS;
1262 	/* TODO: check for incompleteness */
1263 	if (CUR != 0) {
1264 	    xmlCompileStepPattern(ctxt);
1265 	    if (ctxt->error != 0)
1266 		goto error;
1267 	}
1268     } else {
1269         if (CUR == '/') {
1270 	    PUSH(XML_OP_ROOT, NULL, NULL);
1271 	    NEXT;
1272 	    /* Check for incompleteness. */
1273 	    SKIP_BLANKS;
1274 	    if (CUR == 0) {
1275 		ERROR5(NULL, NULL, NULL,
1276 		    "Incomplete expression '%s'.\n", ctxt->base);
1277 		ctxt->error = 1;
1278 		goto error;
1279 	    }
1280 	}
1281 	xmlCompileStepPattern(ctxt);
1282 	if (ctxt->error != 0)
1283 	    goto error;
1284 	SKIP_BLANKS;
1285 	while (CUR == '/') {
1286 	    if (NXT(1) == '/') {
1287 	        PUSH(XML_OP_ANCESTOR, NULL, NULL);
1288 		NEXT;
1289 		NEXT;
1290 		SKIP_BLANKS;
1291 		xmlCompileStepPattern(ctxt);
1292 		if (ctxt->error != 0)
1293 		    goto error;
1294 	    } else {
1295 	        PUSH(XML_OP_PARENT, NULL, NULL);
1296 		NEXT;
1297 		SKIP_BLANKS;
1298 		if (CUR == 0) {
1299 		    ERROR5(NULL, NULL, NULL,
1300 		    "Incomplete expression '%s'.\n", ctxt->base);
1301 		    ctxt->error = 1;
1302 		    goto error;
1303 		}
1304 		xmlCompileStepPattern(ctxt);
1305 		if (ctxt->error != 0)
1306 		    goto error;
1307 	    }
1308 	}
1309     }
1310     if (CUR != 0) {
1311 	ERROR5(NULL, NULL, NULL,
1312 	       "Failed to compile pattern %s\n", ctxt->base);
1313 	ctxt->error = 1;
1314     }
1315 error:
1316     return;
1317 }
1318 
1319 /**
1320  * xmlCompileIDCXPathPath:
1321  * @ctxt:  the compilation context
1322  *
1323  * Compile the Path Pattern and generates a precompiled
1324  * form suitable for fast matching.
1325  *
1326  * [5]    Path    ::=    ('.//')? ( Step '/' )* ( Step | '@' NameTest )
1327  */
1328 static void
xmlCompileIDCXPathPath(xmlPatParserContextPtr ctxt)1329 xmlCompileIDCXPathPath(xmlPatParserContextPtr ctxt) {
1330     SKIP_BLANKS;
1331     if (CUR == '/') {
1332 	ERROR5(NULL, NULL, NULL,
1333 	    "Unexpected selection of the document root in '%s'.\n",
1334 	    ctxt->base);
1335 	goto error;
1336     }
1337     ctxt->comp->flags |= PAT_FROM_CUR;
1338 
1339     if (CUR == '.') {
1340 	/* "." - "self::node()" */
1341 	NEXT;
1342 	SKIP_BLANKS;
1343 	if (CUR == 0) {
1344 	    /*
1345 	    * Selection of the context node.
1346 	    */
1347 	    PUSH(XML_OP_ELEM, NULL, NULL);
1348 	    return;
1349 	}
1350 	if (CUR != '/') {
1351 	    /* TODO: A more meaningful error message. */
1352 	    ERROR5(NULL, NULL, NULL,
1353 	    "Unexpected token after '.' in '%s'.\n", ctxt->base);
1354 	    goto error;
1355 	}
1356 	/* "./" - "self::node()/" */
1357 	NEXT;
1358 	SKIP_BLANKS;
1359 	if (CUR == '/') {
1360 	    if (IS_BLANK_CH(PEEKPREV(1))) {
1361 		/*
1362 		* Disallow "./ /"
1363 		*/
1364 		ERROR5(NULL, NULL, NULL,
1365 		    "Unexpected '/' token in '%s'.\n", ctxt->base);
1366 		goto error;
1367 	    }
1368 	    /* ".//" - "self:node()/descendant-or-self::node()/" */
1369 	    PUSH(XML_OP_ANCESTOR, NULL, NULL);
1370 	    NEXT;
1371 	    SKIP_BLANKS;
1372 	}
1373 	if (CUR == 0)
1374 	    goto error_unfinished;
1375     }
1376     /*
1377     * Process steps.
1378     */
1379     do {
1380 	xmlCompileStepPattern(ctxt);
1381 	if (ctxt->error != 0)
1382 	    goto error;
1383 	SKIP_BLANKS;
1384 	if (CUR != '/')
1385 	    break;
1386 	PUSH(XML_OP_PARENT, NULL, NULL);
1387 	NEXT;
1388 	SKIP_BLANKS;
1389 	if (CUR == '/') {
1390 	    /*
1391 	    * Disallow subsequent '//'.
1392 	    */
1393 	    ERROR5(NULL, NULL, NULL,
1394 		"Unexpected subsequent '//' in '%s'.\n",
1395 		ctxt->base);
1396 	    goto error;
1397 	}
1398 	if (CUR == 0)
1399 	    goto error_unfinished;
1400 
1401     } while (CUR != 0);
1402 
1403     if (CUR != 0) {
1404 	ERROR5(NULL, NULL, NULL,
1405 	    "Failed to compile expression '%s'.\n", ctxt->base);
1406 	ctxt->error = 1;
1407     }
1408     return;
1409 error:
1410     ctxt->error = 1;
1411     return;
1412 
1413 error_unfinished:
1414     ctxt->error = 1;
1415     ERROR5(NULL, NULL, NULL,
1416 	"Unfinished expression '%s'.\n", ctxt->base);
1417     return;
1418 }
1419 
1420 /************************************************************************
1421  *									*
1422  *			The streaming code				*
1423  *									*
1424  ************************************************************************/
1425 
1426 #ifdef DEBUG_STREAMING
1427 static void
xmlDebugStreamComp(xmlStreamCompPtr stream)1428 xmlDebugStreamComp(xmlStreamCompPtr stream) {
1429     int i;
1430 
1431     if (stream == NULL) {
1432         printf("Stream: NULL\n");
1433 	return;
1434     }
1435     printf("Stream: %d steps\n", stream->nbStep);
1436     for (i = 0;i < stream->nbStep;i++) {
1437 	if (stream->steps[i].ns != NULL) {
1438 	    printf("{%s}", stream->steps[i].ns);
1439 	}
1440         if (stream->steps[i].name == NULL) {
1441 	    printf("* ");
1442 	} else {
1443 	    printf("%s ", stream->steps[i].name);
1444 	}
1445 	if (stream->steps[i].flags & XML_STREAM_STEP_ROOT)
1446 	    printf("root ");
1447 	if (stream->steps[i].flags & XML_STREAM_STEP_DESC)
1448 	    printf("// ");
1449 	if (stream->steps[i].flags & XML_STREAM_STEP_FINAL)
1450 	    printf("final ");
1451 	printf("\n");
1452     }
1453 }
1454 static void
xmlDebugStreamCtxt(xmlStreamCtxtPtr ctxt,int match)1455 xmlDebugStreamCtxt(xmlStreamCtxtPtr ctxt, int match) {
1456     int i;
1457 
1458     if (ctxt == NULL) {
1459         printf("Stream: NULL\n");
1460 	return;
1461     }
1462     printf("Stream: level %d, %d states: ", ctxt->level, ctxt->nbState);
1463     if (match)
1464         printf("matches\n");
1465     else
1466         printf("\n");
1467     for (i = 0;i < ctxt->nbState;i++) {
1468         if (ctxt->states[2 * i] < 0)
1469 	    printf(" %d: free\n", i);
1470 	else {
1471 	    printf(" %d: step %d, level %d", i, ctxt->states[2 * i],
1472 	           ctxt->states[(2 * i) + 1]);
1473             if (ctxt->comp->steps[ctxt->states[2 * i]].flags &
1474 	        XML_STREAM_STEP_DESC)
1475 	        printf(" //\n");
1476 	    else
1477 	        printf("\n");
1478 	}
1479     }
1480 }
1481 #endif
1482 /**
1483  * xmlNewStreamComp:
1484  * @size: the number of expected steps
1485  *
1486  * build a new compiled pattern for streaming
1487  *
1488  * Returns the new structure or NULL in case of error.
1489  */
1490 static xmlStreamCompPtr
xmlNewStreamComp(int size)1491 xmlNewStreamComp(int size) {
1492     xmlStreamCompPtr cur;
1493 
1494     if (size < 4)
1495         size  = 4;
1496 
1497     cur = (xmlStreamCompPtr) xmlMalloc(sizeof(xmlStreamComp));
1498     if (cur == NULL) {
1499 	ERROR(NULL, NULL, NULL,
1500 		"xmlNewStreamComp: malloc failed\n");
1501 	return(NULL);
1502     }
1503     memset(cur, 0, sizeof(xmlStreamComp));
1504     cur->steps = (xmlStreamStepPtr) xmlMalloc(size * sizeof(xmlStreamStep));
1505     if (cur->steps == NULL) {
1506 	xmlFree(cur);
1507 	ERROR(NULL, NULL, NULL,
1508 	      "xmlNewStreamComp: malloc failed\n");
1509 	return(NULL);
1510     }
1511     cur->nbStep = 0;
1512     cur->maxStep = size;
1513     return(cur);
1514 }
1515 
1516 /**
1517  * xmlFreeStreamComp:
1518  * @comp: the compiled pattern for streaming
1519  *
1520  * Free the compiled pattern for streaming
1521  */
1522 static void
xmlFreeStreamComp(xmlStreamCompPtr comp)1523 xmlFreeStreamComp(xmlStreamCompPtr comp) {
1524     if (comp != NULL) {
1525         if (comp->steps != NULL)
1526 	    xmlFree(comp->steps);
1527 	if (comp->dict != NULL)
1528 	    xmlDictFree(comp->dict);
1529         xmlFree(comp);
1530     }
1531 }
1532 
1533 /**
1534  * xmlStreamCompAddStep:
1535  * @comp: the compiled pattern for streaming
1536  * @name: the first string, the name, or NULL for *
1537  * @ns: the second step, the namespace name
1538  * @flags: the flags for that step
1539  *
1540  * Add a new step to the compiled pattern
1541  *
1542  * Returns -1 in case of error or the step index if successful
1543  */
1544 static int
xmlStreamCompAddStep(xmlStreamCompPtr comp,const xmlChar * name,const xmlChar * ns,int nodeType,int flags)1545 xmlStreamCompAddStep(xmlStreamCompPtr comp, const xmlChar *name,
1546                      const xmlChar *ns, int nodeType, int flags) {
1547     xmlStreamStepPtr cur;
1548 
1549     if (comp->nbStep >= comp->maxStep) {
1550 	cur = (xmlStreamStepPtr) xmlRealloc(comp->steps,
1551 				 comp->maxStep * 2 * sizeof(xmlStreamStep));
1552 	if (cur == NULL) {
1553 	    ERROR(NULL, NULL, NULL,
1554 		  "xmlNewStreamComp: malloc failed\n");
1555 	    return(-1);
1556 	}
1557 	comp->steps = cur;
1558         comp->maxStep *= 2;
1559     }
1560     cur = &comp->steps[comp->nbStep++];
1561     cur->flags = flags;
1562     cur->name = name;
1563     cur->ns = ns;
1564     cur->nodeType = nodeType;
1565     return(comp->nbStep - 1);
1566 }
1567 
1568 /**
1569  * xmlStreamCompile:
1570  * @comp: the precompiled pattern
1571  *
1572  * Tries to stream compile a pattern
1573  *
1574  * Returns -1 in case of failure and 0 in case of success.
1575  */
1576 static int
xmlStreamCompile(xmlPatternPtr comp)1577 xmlStreamCompile(xmlPatternPtr comp) {
1578     xmlStreamCompPtr stream;
1579     int i, s = 0, root = 0, flags = 0, prevs = -1;
1580     xmlStepOp step;
1581 
1582     if ((comp == NULL) || (comp->steps == NULL))
1583         return(-1);
1584     /*
1585      * special case for .
1586      */
1587     if ((comp->nbStep == 1) &&
1588         (comp->steps[0].op == XML_OP_ELEM) &&
1589 	(comp->steps[0].value == NULL) &&
1590 	(comp->steps[0].value2 == NULL)) {
1591 	stream = xmlNewStreamComp(0);
1592 	if (stream == NULL)
1593 	    return(-1);
1594 	/* Note that the stream will have no steps in this case. */
1595 	stream->flags |= XML_STREAM_FINAL_IS_ANY_NODE;
1596 	comp->stream = stream;
1597 	return(0);
1598     }
1599 
1600     stream = xmlNewStreamComp((comp->nbStep / 2) + 1);
1601     if (stream == NULL)
1602         return(-1);
1603     if (comp->dict != NULL) {
1604         stream->dict = comp->dict;
1605 	xmlDictReference(stream->dict);
1606     }
1607 
1608     i = 0;
1609     if (comp->flags & PAT_FROM_ROOT)
1610 	stream->flags |= XML_STREAM_FROM_ROOT;
1611 
1612     for (;i < comp->nbStep;i++) {
1613 	step = comp->steps[i];
1614         switch (step.op) {
1615 	    case XML_OP_END:
1616 	        break;
1617 	    case XML_OP_ROOT:
1618 	        if (i != 0)
1619 		    goto error;
1620 		root = 1;
1621 		break;
1622 	    case XML_OP_NS:
1623 		s = xmlStreamCompAddStep(stream, NULL, step.value,
1624 		    XML_ELEMENT_NODE, flags);
1625 		if (s < 0)
1626 		    goto error;
1627 		prevs = s;
1628 		flags = 0;
1629 		break;
1630 	    case XML_OP_ATTR:
1631 		flags |= XML_STREAM_STEP_ATTR;
1632 		prevs = -1;
1633 		s = xmlStreamCompAddStep(stream,
1634 		    step.value, step.value2, XML_ATTRIBUTE_NODE, flags);
1635 		flags = 0;
1636 		if (s < 0)
1637 		    goto error;
1638 		break;
1639 	    case XML_OP_ELEM:
1640 	        if ((step.value == NULL) && (step.value2 == NULL)) {
1641 		    /*
1642 		    * We have a "." or "self::node()" here.
1643 		    * Eliminate redundant self::node() tests like in "/./."
1644 		    * or "//./"
1645 		    * The only case we won't eliminate is "//.", i.e. if
1646 		    * self::node() is the last node test and we had
1647 		    * continuation somewhere beforehand.
1648 		    */
1649 		    if ((comp->nbStep == i + 1) &&
1650 			(flags & XML_STREAM_STEP_DESC)) {
1651 			/*
1652 			* Mark the special case where the expression resolves
1653 			* to any type of node.
1654 			*/
1655 			if (comp->nbStep == i + 1) {
1656 			    stream->flags |= XML_STREAM_FINAL_IS_ANY_NODE;
1657 			}
1658 			flags |= XML_STREAM_STEP_NODE;
1659 			s = xmlStreamCompAddStep(stream, NULL, NULL,
1660 			    XML_STREAM_ANY_NODE, flags);
1661 			if (s < 0)
1662 			    goto error;
1663 			flags = 0;
1664 			/*
1665 			* If there was a previous step, mark it to be added to
1666 			* the result node-set; this is needed since only
1667 			* the last step will be marked as "final" and only
1668 			* "final" nodes are added to the resulting set.
1669 			*/
1670 			if (prevs != -1) {
1671 			    stream->steps[prevs].flags |= XML_STREAM_STEP_IN_SET;
1672 			    prevs = -1;
1673 			}
1674 			break;
1675 
1676 		    } else {
1677 			/* Just skip this one. */
1678 			continue;
1679 		    }
1680 		}
1681 		/* An element node. */
1682 	        s = xmlStreamCompAddStep(stream, step.value, step.value2,
1683 		    XML_ELEMENT_NODE, flags);
1684 		if (s < 0)
1685 		    goto error;
1686 		prevs = s;
1687 		flags = 0;
1688 		break;
1689 	    case XML_OP_CHILD:
1690 		/* An element node child. */
1691 	        s = xmlStreamCompAddStep(stream, step.value, step.value2,
1692 		    XML_ELEMENT_NODE, flags);
1693 		if (s < 0)
1694 		    goto error;
1695 		prevs = s;
1696 		flags = 0;
1697 		break;
1698 	    case XML_OP_ALL:
1699 	        s = xmlStreamCompAddStep(stream, NULL, NULL,
1700 		    XML_ELEMENT_NODE, flags);
1701 		if (s < 0)
1702 		    goto error;
1703 		prevs = s;
1704 		flags = 0;
1705 		break;
1706 	    case XML_OP_PARENT:
1707 	        break;
1708 	    case XML_OP_ANCESTOR:
1709 		/* Skip redundant continuations. */
1710 		if (flags & XML_STREAM_STEP_DESC)
1711 		    break;
1712 	        flags |= XML_STREAM_STEP_DESC;
1713 		/*
1714 		* Mark the expression as having "//".
1715 		*/
1716 		if ((stream->flags & XML_STREAM_DESC) == 0)
1717 		    stream->flags |= XML_STREAM_DESC;
1718 		break;
1719 	}
1720     }
1721     if ((! root) && (comp->flags & XML_PATTERN_NOTPATTERN) == 0) {
1722 	/*
1723 	* If this should behave like a real pattern, we will mark
1724 	* the first step as having "//", to be reentrant on every
1725 	* tree level.
1726 	*/
1727 	if ((stream->flags & XML_STREAM_DESC) == 0)
1728 	    stream->flags |= XML_STREAM_DESC;
1729 
1730 	if (stream->nbStep > 0) {
1731 	    if ((stream->steps[0].flags & XML_STREAM_STEP_DESC) == 0)
1732 		stream->steps[0].flags |= XML_STREAM_STEP_DESC;
1733 	}
1734     }
1735     if (stream->nbStep <= s)
1736 	goto error;
1737     stream->steps[s].flags |= XML_STREAM_STEP_FINAL;
1738     if (root)
1739 	stream->steps[0].flags |= XML_STREAM_STEP_ROOT;
1740 #ifdef DEBUG_STREAMING
1741     xmlDebugStreamComp(stream);
1742 #endif
1743     comp->stream = stream;
1744     return(0);
1745 error:
1746     xmlFreeStreamComp(stream);
1747     return(0);
1748 }
1749 
1750 /**
1751  * xmlNewStreamCtxt:
1752  * @size: the number of expected states
1753  *
1754  * build a new stream context
1755  *
1756  * Returns the new structure or NULL in case of error.
1757  */
1758 static xmlStreamCtxtPtr
xmlNewStreamCtxt(xmlStreamCompPtr stream)1759 xmlNewStreamCtxt(xmlStreamCompPtr stream) {
1760     xmlStreamCtxtPtr cur;
1761 
1762     cur = (xmlStreamCtxtPtr) xmlMalloc(sizeof(xmlStreamCtxt));
1763     if (cur == NULL) {
1764 	ERROR(NULL, NULL, NULL,
1765 		"xmlNewStreamCtxt: malloc failed\n");
1766 	return(NULL);
1767     }
1768     memset(cur, 0, sizeof(xmlStreamCtxt));
1769     cur->states = (int *) xmlMalloc(4 * 2 * sizeof(int));
1770     if (cur->states == NULL) {
1771 	xmlFree(cur);
1772 	ERROR(NULL, NULL, NULL,
1773 	      "xmlNewStreamCtxt: malloc failed\n");
1774 	return(NULL);
1775     }
1776     cur->nbState = 0;
1777     cur->maxState = 4;
1778     cur->level = 0;
1779     cur->comp = stream;
1780     cur->blockLevel = -1;
1781     return(cur);
1782 }
1783 
1784 /**
1785  * xmlFreeStreamCtxt:
1786  * @stream: the stream context
1787  *
1788  * Free the stream context
1789  */
1790 void
xmlFreeStreamCtxt(xmlStreamCtxtPtr stream)1791 xmlFreeStreamCtxt(xmlStreamCtxtPtr stream) {
1792     xmlStreamCtxtPtr next;
1793 
1794     while (stream != NULL) {
1795         next = stream->next;
1796         if (stream->states != NULL)
1797 	    xmlFree(stream->states);
1798         xmlFree(stream);
1799 	stream = next;
1800     }
1801 }
1802 
1803 /**
1804  * xmlStreamCtxtAddState:
1805  * @comp: the stream context
1806  * @idx: the step index for that streaming state
1807  *
1808  * Add a new state to the stream context
1809  *
1810  * Returns -1 in case of error or the state index if successful
1811  */
1812 static int
xmlStreamCtxtAddState(xmlStreamCtxtPtr comp,int idx,int level)1813 xmlStreamCtxtAddState(xmlStreamCtxtPtr comp, int idx, int level) {
1814     int i;
1815     for (i = 0;i < comp->nbState;i++) {
1816         if (comp->states[2 * i] < 0) {
1817 	    comp->states[2 * i] = idx;
1818 	    comp->states[2 * i + 1] = level;
1819 	    return(i);
1820 	}
1821     }
1822     if (comp->nbState >= comp->maxState) {
1823         int *cur;
1824 
1825 	cur = (int *) xmlRealloc(comp->states,
1826 				 comp->maxState * 4 * sizeof(int));
1827 	if (cur == NULL) {
1828 	    ERROR(NULL, NULL, NULL,
1829 		  "xmlNewStreamCtxt: malloc failed\n");
1830 	    return(-1);
1831 	}
1832 	comp->states = cur;
1833         comp->maxState *= 2;
1834     }
1835     comp->states[2 * comp->nbState] = idx;
1836     comp->states[2 * comp->nbState++ + 1] = level;
1837     return(comp->nbState - 1);
1838 }
1839 
1840 /**
1841  * xmlStreamPushInternal:
1842  * @stream: the stream context
1843  * @name: the current name
1844  * @ns: the namespace name
1845  * @nodeType: the type of the node
1846  *
1847  * Push new data onto the stream. NOTE: if the call xmlPatterncompile()
1848  * indicated a dictionary, then strings for name and ns will be expected
1849  * to come from the dictionary.
1850  * Both @name and @ns being NULL means the / i.e. the root of the document.
1851  * This can also act as a reset.
1852  *
1853  * Returns: -1 in case of error, 1 if the current state in the stream is a
1854  *    match and 0 otherwise.
1855  */
1856 static int
xmlStreamPushInternal(xmlStreamCtxtPtr stream,const xmlChar * name,const xmlChar * ns,int nodeType)1857 xmlStreamPushInternal(xmlStreamCtxtPtr stream,
1858 		      const xmlChar *name, const xmlChar *ns,
1859 		      int nodeType) {
1860     int ret = 0, err = 0, final = 0, tmp, i, m, match, stepNr, desc;
1861     xmlStreamCompPtr comp;
1862     xmlStreamStep step;
1863 #ifdef DEBUG_STREAMING
1864     xmlStreamCtxtPtr orig = stream;
1865 #endif
1866 
1867     if ((stream == NULL) || (stream->nbState < 0))
1868         return(-1);
1869 
1870     while (stream != NULL) {
1871 	comp = stream->comp;
1872 
1873 	if ((nodeType == XML_ELEMENT_NODE) &&
1874 	    (name == NULL) && (ns == NULL)) {
1875 	    /* We have a document node here (or a reset). */
1876 	    stream->nbState = 0;
1877 	    stream->level = 0;
1878 	    stream->blockLevel = -1;
1879 	    if (comp->flags & XML_STREAM_FROM_ROOT) {
1880 		if (comp->nbStep == 0) {
1881 		    /* TODO: We have a "/." here? */
1882 		    ret = 1;
1883 		} else {
1884 		    if ((comp->nbStep == 1) &&
1885 			(comp->steps[0].nodeType == XML_STREAM_ANY_NODE) &&
1886 			(comp->steps[0].flags & XML_STREAM_STEP_DESC))
1887 		    {
1888 			/*
1889 			* In the case of "//." the document node will match
1890 			* as well.
1891 			*/
1892 			ret = 1;
1893 		    } else if (comp->steps[0].flags & XML_STREAM_STEP_ROOT) {
1894 			/* TODO: Do we need this ? */
1895 			tmp = xmlStreamCtxtAddState(stream, 0, 0);
1896 			if (tmp < 0)
1897 			    err++;
1898 		    }
1899 		}
1900 	    }
1901 	    stream = stream->next;
1902 	    continue; /* while */
1903 	}
1904 
1905 	/*
1906 	* Fast check for ".".
1907 	*/
1908 	if (comp->nbStep == 0) {
1909 	    /*
1910 	     * / and . are handled at the XPath node set creation
1911 	     * level by checking min depth
1912 	     */
1913 	    if (stream->flags & XML_PATTERN_XPATH) {
1914 		stream = stream->next;
1915 		continue; /* while */
1916 	    }
1917 	    /*
1918 	    * For non-pattern like evaluation like XML Schema IDCs
1919 	    * or traditional XPath expressions, this will match if
1920 	    * we are at the first level only, otherwise on every level.
1921 	    */
1922 	    if ((nodeType != XML_ATTRIBUTE_NODE) &&
1923 		(((stream->flags & XML_PATTERN_NOTPATTERN) == 0) ||
1924 		(stream->level == 0))) {
1925 		    ret = 1;
1926 	    }
1927 	    stream->level++;
1928 	    goto stream_next;
1929 	}
1930 	if (stream->blockLevel != -1) {
1931 	    /*
1932 	    * Skip blocked expressions.
1933 	    */
1934 	    stream->level++;
1935 	    goto stream_next;
1936 	}
1937 
1938 	if ((nodeType != XML_ELEMENT_NODE) &&
1939 	    (nodeType != XML_ATTRIBUTE_NODE) &&
1940 	    ((comp->flags & XML_STREAM_FINAL_IS_ANY_NODE) == 0)) {
1941 	    /*
1942 	    * No need to process nodes of other types if we don't
1943 	    * resolve to those types.
1944 	    * TODO: Do we need to block the context here?
1945 	    */
1946 	    stream->level++;
1947 	    goto stream_next;
1948 	}
1949 
1950 	/*
1951 	 * Check evolution of existing states
1952 	 */
1953 	i = 0;
1954 	m = stream->nbState;
1955 	while (i < m) {
1956 	    if ((comp->flags & XML_STREAM_DESC) == 0) {
1957 		/*
1958 		* If there is no "//", then only the last
1959 		* added state is of interest.
1960 		*/
1961 		stepNr = stream->states[2 * (stream->nbState -1)];
1962 		/*
1963 		* TODO: Security check, should not happen, remove it.
1964 		*/
1965 		if (stream->states[(2 * (stream->nbState -1)) + 1] <
1966 		    stream->level) {
1967 		    return (-1);
1968 		}
1969 		desc = 0;
1970 		/* loop-stopper */
1971 		i = m;
1972 	    } else {
1973 		/*
1974 		* If there are "//", then we need to process every "//"
1975 		* occuring in the states, plus any other state for this
1976 		* level.
1977 		*/
1978 		stepNr = stream->states[2 * i];
1979 
1980 		/* TODO: should not happen anymore: dead states */
1981 		if (stepNr < 0)
1982 		    goto next_state;
1983 
1984 		tmp = stream->states[(2 * i) + 1];
1985 
1986 		/* skip new states just added */
1987 		if (tmp > stream->level)
1988 		    goto next_state;
1989 
1990 		/* skip states at ancestor levels, except if "//" */
1991 		desc = comp->steps[stepNr].flags & XML_STREAM_STEP_DESC;
1992 		if ((tmp < stream->level) && (!desc))
1993 		    goto next_state;
1994 	    }
1995 	    /*
1996 	    * Check for correct node-type.
1997 	    */
1998 	    step = comp->steps[stepNr];
1999 	    if (step.nodeType != nodeType) {
2000 		if (step.nodeType == XML_ATTRIBUTE_NODE) {
2001 		    /*
2002 		    * Block this expression for deeper evaluation.
2003 		    */
2004 		    if ((comp->flags & XML_STREAM_DESC) == 0)
2005 			stream->blockLevel = stream->level +1;
2006 		    goto next_state;
2007 		} else if (step.nodeType != XML_STREAM_ANY_NODE)
2008 		    goto next_state;
2009 	    }
2010 	    /*
2011 	    * Compare local/namespace-name.
2012 	    */
2013 	    match = 0;
2014 	    if (step.nodeType == XML_STREAM_ANY_NODE) {
2015 		match = 1;
2016 	    } else if (step.name == NULL) {
2017 		if (step.ns == NULL) {
2018 		    /*
2019 		    * This lets through all elements/attributes.
2020 		    */
2021 		    match = 1;
2022 		} else if (ns != NULL)
2023 		    match = xmlStrEqual(step.ns, ns);
2024 	    } else if (((step.ns != NULL) == (ns != NULL)) &&
2025 		(name != NULL) &&
2026 		(step.name[0] == name[0]) &&
2027 		xmlStrEqual(step.name, name) &&
2028 		((step.ns == ns) || xmlStrEqual(step.ns, ns)))
2029 	    {
2030 		match = 1;
2031 	    }
2032 #if 0
2033 /*
2034 * TODO: Pointer comparison won't work, since not guaranteed that the given
2035 *  values are in the same dict; especially if it's the namespace name,
2036 *  normally coming from ns->href. We need a namespace dict mechanism !
2037 */
2038 	    } else if (comp->dict) {
2039 		if (step.name == NULL) {
2040 		    if (step.ns == NULL)
2041 			match = 1;
2042 		    else
2043 			match = (step.ns == ns);
2044 		} else {
2045 		    match = ((step.name == name) && (step.ns == ns));
2046 		}
2047 #endif /* if 0 ------------------------------------------------------- */
2048 	    if (match) {
2049 		final = step.flags & XML_STREAM_STEP_FINAL;
2050 		if (desc) {
2051 		    if (final) {
2052 			ret = 1;
2053 		    } else {
2054 			/* descending match create a new state */
2055 			xmlStreamCtxtAddState(stream, stepNr + 1,
2056 			                      stream->level + 1);
2057 		    }
2058 		} else {
2059 		    if (final) {
2060 			ret = 1;
2061 		    } else {
2062 			xmlStreamCtxtAddState(stream, stepNr + 1,
2063 			                      stream->level + 1);
2064 		    }
2065 		}
2066 		if ((ret != 1) && (step.flags & XML_STREAM_STEP_IN_SET)) {
2067 		    /*
2068 		    * Check if we have a special case like "foo/bar//.", where
2069 		    * "foo" is selected as well.
2070 		    */
2071 		    ret = 1;
2072 		}
2073 	    }
2074 	    if (((comp->flags & XML_STREAM_DESC) == 0) &&
2075 		((! match) || final))  {
2076 		/*
2077 		* Mark this expression as blocked for any evaluation at
2078 		* deeper levels. Note that this includes "/foo"
2079 		* expressions if the *pattern* behaviour is used.
2080 		*/
2081 		stream->blockLevel = stream->level +1;
2082 	    }
2083 next_state:
2084 	    i++;
2085 	}
2086 
2087 	stream->level++;
2088 
2089 	/*
2090 	* Re/enter the expression.
2091 	* Don't reenter if it's an absolute expression like "/foo",
2092 	*   except "//foo".
2093 	*/
2094 	step = comp->steps[0];
2095 	if (step.flags & XML_STREAM_STEP_ROOT)
2096 	    goto stream_next;
2097 
2098 	desc = step.flags & XML_STREAM_STEP_DESC;
2099 	if (stream->flags & XML_PATTERN_NOTPATTERN) {
2100 	    /*
2101 	    * Re/enter the expression if it is a "descendant" one,
2102 	    * or if we are at the 1st level of evaluation.
2103 	    */
2104 
2105 	    if (stream->level == 1) {
2106 		if (XML_STREAM_XS_IDC(stream)) {
2107 		    /*
2108 		    * XS-IDC: The missing "self::node()" will always
2109 		    * match the first given node.
2110 		    */
2111 		    goto stream_next;
2112 		} else
2113 		    goto compare;
2114 	    }
2115 	    /*
2116 	    * A "//" is always reentrant.
2117 	    */
2118 	    if (desc)
2119 		goto compare;
2120 
2121 	    /*
2122 	    * XS-IDC: Process the 2nd level, since the missing
2123 	    * "self::node()" is responsible for the 2nd level being
2124 	    * the real start level.
2125 	    */
2126 	    if ((stream->level == 2) && XML_STREAM_XS_IDC(stream))
2127 		goto compare;
2128 
2129 	    goto stream_next;
2130 	}
2131 
2132 compare:
2133 	/*
2134 	* Check expected node-type.
2135 	*/
2136 	if (step.nodeType != nodeType) {
2137 	    if (nodeType == XML_ATTRIBUTE_NODE)
2138 		goto stream_next;
2139 	    else if (step.nodeType != XML_STREAM_ANY_NODE)
2140 		goto stream_next;
2141 	}
2142 	/*
2143 	* Compare local/namespace-name.
2144 	*/
2145 	match = 0;
2146 	if (step.nodeType == XML_STREAM_ANY_NODE) {
2147 	    match = 1;
2148 	} else if (step.name == NULL) {
2149 	    if (step.ns == NULL) {
2150 		/*
2151 		* This lets through all elements/attributes.
2152 		*/
2153 		match = 1;
2154 	    } else if (ns != NULL)
2155 		match = xmlStrEqual(step.ns, ns);
2156 	} else if (((step.ns != NULL) == (ns != NULL)) &&
2157 	    (name != NULL) &&
2158 	    (step.name[0] == name[0]) &&
2159 	    xmlStrEqual(step.name, name) &&
2160 	    ((step.ns == ns) || xmlStrEqual(step.ns, ns)))
2161 	{
2162 	    match = 1;
2163 	}
2164 	final = step.flags & XML_STREAM_STEP_FINAL;
2165 	if (match) {
2166 	    if (final)
2167 		ret = 1;
2168 	    else
2169 		xmlStreamCtxtAddState(stream, 1, stream->level);
2170 	    if ((ret != 1) && (step.flags & XML_STREAM_STEP_IN_SET)) {
2171 		/*
2172 		* Check if we have a special case like "foo//.", where
2173 		* "foo" is selected as well.
2174 		*/
2175 		ret = 1;
2176 	    }
2177 	}
2178 	if (((comp->flags & XML_STREAM_DESC) == 0) &&
2179 	    ((! match) || final))  {
2180 	    /*
2181 	    * Mark this expression as blocked for any evaluation at
2182 	    * deeper levels.
2183 	    */
2184 	    stream->blockLevel = stream->level;
2185 	}
2186 
2187 stream_next:
2188         stream = stream->next;
2189     } /* while stream != NULL */
2190 
2191     if (err > 0)
2192         ret = -1;
2193 #ifdef DEBUG_STREAMING
2194     xmlDebugStreamCtxt(orig, ret);
2195 #endif
2196     return(ret);
2197 }
2198 
2199 /**
2200  * xmlStreamPush:
2201  * @stream: the stream context
2202  * @name: the current name
2203  * @ns: the namespace name
2204  *
2205  * Push new data onto the stream. NOTE: if the call xmlPatterncompile()
2206  * indicated a dictionary, then strings for name and ns will be expected
2207  * to come from the dictionary.
2208  * Both @name and @ns being NULL means the / i.e. the root of the document.
2209  * This can also act as a reset.
2210  * Otherwise the function will act as if it has been given an element-node.
2211  *
2212  * Returns: -1 in case of error, 1 if the current state in the stream is a
2213  *    match and 0 otherwise.
2214  */
2215 int
xmlStreamPush(xmlStreamCtxtPtr stream,const xmlChar * name,const xmlChar * ns)2216 xmlStreamPush(xmlStreamCtxtPtr stream,
2217               const xmlChar *name, const xmlChar *ns) {
2218     return (xmlStreamPushInternal(stream, name, ns, (int) XML_ELEMENT_NODE));
2219 }
2220 
2221 /**
2222  * xmlStreamPushNode:
2223  * @stream: the stream context
2224  * @name: the current name
2225  * @ns: the namespace name
2226  * @nodeType: the type of the node being pushed
2227  *
2228  * Push new data onto the stream. NOTE: if the call xmlPatterncompile()
2229  * indicated a dictionary, then strings for name and ns will be expected
2230  * to come from the dictionary.
2231  * Both @name and @ns being NULL means the / i.e. the root of the document.
2232  * This can also act as a reset.
2233  * Different from xmlStreamPush() this function can be fed with nodes of type:
2234  * element-, attribute-, text-, cdata-section-, comment- and
2235  * processing-instruction-node.
2236  *
2237  * Returns: -1 in case of error, 1 if the current state in the stream is a
2238  *    match and 0 otherwise.
2239  */
2240 int
xmlStreamPushNode(xmlStreamCtxtPtr stream,const xmlChar * name,const xmlChar * ns,int nodeType)2241 xmlStreamPushNode(xmlStreamCtxtPtr stream,
2242 		  const xmlChar *name, const xmlChar *ns,
2243 		  int nodeType)
2244 {
2245     return (xmlStreamPushInternal(stream, name, ns,
2246 	nodeType));
2247 }
2248 
2249 /**
2250 * xmlStreamPushAttr:
2251 * @stream: the stream context
2252 * @name: the current name
2253 * @ns: the namespace name
2254 *
2255 * Push new attribute data onto the stream. NOTE: if the call xmlPatterncompile()
2256 * indicated a dictionary, then strings for name and ns will be expected
2257 * to come from the dictionary.
2258 * Both @name and @ns being NULL means the / i.e. the root of the document.
2259 * This can also act as a reset.
2260 * Otherwise the function will act as if it has been given an attribute-node.
2261 *
2262 * Returns: -1 in case of error, 1 if the current state in the stream is a
2263 *    match and 0 otherwise.
2264 */
2265 int
xmlStreamPushAttr(xmlStreamCtxtPtr stream,const xmlChar * name,const xmlChar * ns)2266 xmlStreamPushAttr(xmlStreamCtxtPtr stream,
2267 		  const xmlChar *name, const xmlChar *ns) {
2268     return (xmlStreamPushInternal(stream, name, ns, (int) XML_ATTRIBUTE_NODE));
2269 }
2270 
2271 /**
2272  * xmlStreamPop:
2273  * @stream: the stream context
2274  *
2275  * push one level from the stream.
2276  *
2277  * Returns: -1 in case of error, 0 otherwise.
2278  */
2279 int
xmlStreamPop(xmlStreamCtxtPtr stream)2280 xmlStreamPop(xmlStreamCtxtPtr stream) {
2281     int i, lev;
2282 
2283     if (stream == NULL)
2284         return(-1);
2285     while (stream != NULL) {
2286 	/*
2287 	* Reset block-level.
2288 	*/
2289 	if (stream->blockLevel == stream->level)
2290 	    stream->blockLevel = -1;
2291 
2292 	/*
2293 	 *  stream->level can be zero when XML_FINAL_IS_ANY_NODE is set
2294 	 *  (see the thread at
2295 	 *  http://mail.gnome.org/archives/xslt/2008-July/msg00027.html)
2296 	 */
2297 	if (stream->level)
2298 	    stream->level--;
2299 	/*
2300 	 * Check evolution of existing states
2301 	 */
2302 	for (i = stream->nbState -1; i >= 0; i--) {
2303 	    /* discard obsoleted states */
2304 	    lev = stream->states[(2 * i) + 1];
2305 	    if (lev > stream->level)
2306 		stream->nbState--;
2307 	    if (lev <= stream->level)
2308 		break;
2309 	}
2310 	stream = stream->next;
2311     }
2312     return(0);
2313 }
2314 
2315 /**
2316  * xmlStreamWantsAnyNode:
2317  * @streamCtxt: the stream context
2318  *
2319  * Query if the streaming pattern additionally needs to be fed with
2320  * text-, cdata-section-, comment- and processing-instruction-nodes.
2321  * If the result is 0 then only element-nodes and attribute-nodes
2322  * need to be pushed.
2323  *
2324  * Returns: 1 in case of need of nodes of the above described types,
2325  *          0 otherwise. -1 on API errors.
2326  */
2327 int
xmlStreamWantsAnyNode(xmlStreamCtxtPtr streamCtxt)2328 xmlStreamWantsAnyNode(xmlStreamCtxtPtr streamCtxt)
2329 {
2330     if (streamCtxt == NULL)
2331 	return(-1);
2332     while (streamCtxt != NULL) {
2333 	if (streamCtxt->comp->flags & XML_STREAM_FINAL_IS_ANY_NODE)
2334 	    return(1);
2335 	streamCtxt = streamCtxt->next;
2336     }
2337     return(0);
2338 }
2339 
2340 /************************************************************************
2341  *									*
2342  *			The public interfaces				*
2343  *									*
2344  ************************************************************************/
2345 
2346 /**
2347  * xmlPatterncompile:
2348  * @pattern: the pattern to compile
2349  * @dict: an optional dictionary for interned strings
2350  * @flags: compilation flags, see xmlPatternFlags
2351  * @namespaces: the prefix definitions, array of [URI, prefix] or NULL
2352  *
2353  * Compile a pattern.
2354  *
2355  * Returns the compiled form of the pattern or NULL in case of error
2356  */
2357 xmlPatternPtr
xmlPatterncompile(const xmlChar * pattern,xmlDict * dict,int flags,const xmlChar ** namespaces)2358 xmlPatterncompile(const xmlChar *pattern, xmlDict *dict, int flags,
2359                   const xmlChar **namespaces) {
2360     xmlPatternPtr ret = NULL, cur;
2361     xmlPatParserContextPtr ctxt = NULL;
2362     const xmlChar *or, *start;
2363     xmlChar *tmp = NULL;
2364     int type = 0;
2365     int streamable = 1;
2366 
2367     if (pattern == NULL)
2368         return(NULL);
2369 
2370     start = pattern;
2371     or = start;
2372     while (*or != 0) {
2373 	tmp = NULL;
2374 	while ((*or != 0) && (*or != '|')) or++;
2375         if (*or == 0)
2376 	    ctxt = xmlNewPatParserContext(start, dict, namespaces);
2377 	else {
2378 	    tmp = xmlStrndup(start, or - start);
2379 	    if (tmp != NULL) {
2380 		ctxt = xmlNewPatParserContext(tmp, dict, namespaces);
2381 	    }
2382 	    or++;
2383 	}
2384 	if (ctxt == NULL) goto error;
2385 	cur = xmlNewPattern();
2386 	if (cur == NULL) goto error;
2387 	/*
2388 	* Assign string dict.
2389 	*/
2390 	if (dict) {
2391 	    cur->dict = dict;
2392 	    xmlDictReference(dict);
2393 	}
2394 	if (ret == NULL)
2395 	    ret = cur;
2396 	else {
2397 	    cur->next = ret->next;
2398 	    ret->next = cur;
2399 	}
2400 	cur->flags = flags;
2401 	ctxt->comp = cur;
2402 
2403 	if (XML_STREAM_XS_IDC(cur))
2404 	    xmlCompileIDCXPathPath(ctxt);
2405 	else
2406 	    xmlCompilePathPattern(ctxt);
2407 	if (ctxt->error != 0)
2408 	    goto error;
2409 	xmlFreePatParserContext(ctxt);
2410 	ctxt = NULL;
2411 
2412 
2413         if (streamable) {
2414 	    if (type == 0) {
2415 	        type = cur->flags & (PAT_FROM_ROOT | PAT_FROM_CUR);
2416 	    } else if (type == PAT_FROM_ROOT) {
2417 	        if (cur->flags & PAT_FROM_CUR)
2418 		    streamable = 0;
2419 	    } else if (type == PAT_FROM_CUR) {
2420 	        if (cur->flags & PAT_FROM_ROOT)
2421 		    streamable = 0;
2422 	    }
2423 	}
2424 	if (streamable)
2425 	    xmlStreamCompile(cur);
2426 	if (xmlReversePattern(cur) < 0)
2427 	    goto error;
2428 	if (tmp != NULL) {
2429 	    xmlFree(tmp);
2430 	    tmp = NULL;
2431 	}
2432 	start = or;
2433     }
2434     if (streamable == 0) {
2435         cur = ret;
2436 	while (cur != NULL) {
2437 	    if (cur->stream != NULL) {
2438 		xmlFreeStreamComp(cur->stream);
2439 		cur->stream = NULL;
2440 	    }
2441 	    cur = cur->next;
2442 	}
2443     }
2444 
2445     return(ret);
2446 error:
2447     if (ctxt != NULL) xmlFreePatParserContext(ctxt);
2448     if (ret != NULL) xmlFreePattern(ret);
2449     if (tmp != NULL) xmlFree(tmp);
2450     return(NULL);
2451 }
2452 
2453 /**
2454  * xmlPatternMatch:
2455  * @comp: the precompiled pattern
2456  * @node: a node
2457  *
2458  * Test whether the node matches the pattern
2459  *
2460  * Returns 1 if it matches, 0 if it doesn't and -1 in case of failure
2461  */
2462 int
xmlPatternMatch(xmlPatternPtr comp,xmlNodePtr node)2463 xmlPatternMatch(xmlPatternPtr comp, xmlNodePtr node)
2464 {
2465     int ret = 0;
2466 
2467     if ((comp == NULL) || (node == NULL))
2468         return(-1);
2469 
2470     while (comp != NULL) {
2471         ret = xmlPatMatch(comp, node);
2472 	if (ret != 0)
2473 	    return(ret);
2474 	comp = comp->next;
2475     }
2476     return(ret);
2477 }
2478 
2479 /**
2480  * xmlPatternGetStreamCtxt:
2481  * @comp: the precompiled pattern
2482  *
2483  * Get a streaming context for that pattern
2484  * Use xmlFreeStreamCtxt to free the context.
2485  *
2486  * Returns a pointer to the context or NULL in case of failure
2487  */
2488 xmlStreamCtxtPtr
xmlPatternGetStreamCtxt(xmlPatternPtr comp)2489 xmlPatternGetStreamCtxt(xmlPatternPtr comp)
2490 {
2491     xmlStreamCtxtPtr ret = NULL, cur;
2492 
2493     if ((comp == NULL) || (comp->stream == NULL))
2494         return(NULL);
2495 
2496     while (comp != NULL) {
2497         if (comp->stream == NULL)
2498 	    goto failed;
2499 	cur = xmlNewStreamCtxt(comp->stream);
2500 	if (cur == NULL)
2501 	    goto failed;
2502 	if (ret == NULL)
2503 	    ret = cur;
2504 	else {
2505 	    cur->next = ret->next;
2506 	    ret->next = cur;
2507 	}
2508 	cur->flags = comp->flags;
2509 	comp = comp->next;
2510     }
2511     return(ret);
2512 failed:
2513     xmlFreeStreamCtxt(ret);
2514     return(NULL);
2515 }
2516 
2517 /**
2518  * xmlPatternStreamable:
2519  * @comp: the precompiled pattern
2520  *
2521  * Check if the pattern is streamable i.e. xmlPatternGetStreamCtxt()
2522  * should work.
2523  *
2524  * Returns 1 if streamable, 0 if not and -1 in case of error.
2525  */
2526 int
xmlPatternStreamable(xmlPatternPtr comp)2527 xmlPatternStreamable(xmlPatternPtr comp) {
2528     if (comp == NULL)
2529         return(-1);
2530     while (comp != NULL) {
2531         if (comp->stream == NULL)
2532 	    return(0);
2533 	comp = comp->next;
2534     }
2535     return(1);
2536 }
2537 
2538 /**
2539  * xmlPatternMaxDepth:
2540  * @comp: the precompiled pattern
2541  *
2542  * Check the maximum depth reachable by a pattern
2543  *
2544  * Returns -2 if no limit (using //), otherwise the depth,
2545  *         and -1 in case of error
2546  */
2547 int
xmlPatternMaxDepth(xmlPatternPtr comp)2548 xmlPatternMaxDepth(xmlPatternPtr comp) {
2549     int ret = 0, i;
2550     if (comp == NULL)
2551         return(-1);
2552     while (comp != NULL) {
2553         if (comp->stream == NULL)
2554 	    return(-1);
2555 	for (i = 0;i < comp->stream->nbStep;i++)
2556 	    if (comp->stream->steps[i].flags & XML_STREAM_STEP_DESC)
2557 	        return(-2);
2558 	if (comp->stream->nbStep > ret)
2559 	    ret = comp->stream->nbStep;
2560 	comp = comp->next;
2561     }
2562     return(ret);
2563 }
2564 
2565 /**
2566  * xmlPatternMinDepth:
2567  * @comp: the precompiled pattern
2568  *
2569  * Check the minimum depth reachable by a pattern, 0 mean the / or . are
2570  * part of the set.
2571  *
2572  * Returns -1 in case of error otherwise the depth,
2573  *
2574  */
2575 int
xmlPatternMinDepth(xmlPatternPtr comp)2576 xmlPatternMinDepth(xmlPatternPtr comp) {
2577     int ret = 12345678;
2578     if (comp == NULL)
2579         return(-1);
2580     while (comp != NULL) {
2581         if (comp->stream == NULL)
2582 	    return(-1);
2583 	if (comp->stream->nbStep < ret)
2584 	    ret = comp->stream->nbStep;
2585 	if (ret == 0)
2586 	    return(0);
2587 	comp = comp->next;
2588     }
2589     return(ret);
2590 }
2591 
2592 /**
2593  * xmlPatternFromRoot:
2594  * @comp: the precompiled pattern
2595  *
2596  * Check if the pattern must be looked at from the root.
2597  *
2598  * Returns 1 if true, 0 if false and -1 in case of error
2599  */
2600 int
xmlPatternFromRoot(xmlPatternPtr comp)2601 xmlPatternFromRoot(xmlPatternPtr comp) {
2602     if (comp == NULL)
2603         return(-1);
2604     while (comp != NULL) {
2605         if (comp->stream == NULL)
2606 	    return(-1);
2607 	if (comp->flags & PAT_FROM_ROOT)
2608 	    return(1);
2609 	comp = comp->next;
2610     }
2611     return(0);
2612 
2613 }
2614 
2615 #define bottom_pattern
2616 #include "elfgcchack.h"
2617 #endif /* LIBXML_PATTERN_ENABLED */
2618