1/*
2 * xpointer.c : Code to handle XML Pointer
3 *
4 * Base implementation was made accordingly to
5 * W3C Candidate Recommendation 7 June 2000
6 * http://www.w3.org/TR/2000/CR-xptr-20000607
7 *
8 * Added support for the element() scheme described in:
9 * W3C Proposed Recommendation 13 November 2002
10 * http://www.w3.org/TR/2002/PR-xptr-element-20021113/
11 *
12 * See Copyright for the status of this software.
13 *
14 * daniel@veillard.com
15 */
16
17#define IN_LIBXML
18#include "libxml.h"
19
20/*
21 * TODO: better handling of error cases, the full expression should
22 *       be parsed beforehand instead of a progressive evaluation
23 * TODO: Access into entities references are not supported now ...
24 *       need a start to be able to pop out of entities refs since
25 *       parent is the endity declaration, not the ref.
26 */
27
28#include <string.h>
29#include <libxml/xpointer.h>
30#include <libxml/xmlmemory.h>
31#include <libxml/parserInternals.h>
32#include <libxml/uri.h>
33#include <libxml/xpath.h>
34#include <libxml/xpathInternals.h>
35#include <libxml/xmlerror.h>
36#include <libxml/globals.h>
37
38#ifdef LIBXML_XPTR_ENABLED
39
40/* Add support of the xmlns() xpointer scheme to initialize the namespaces */
41#define XPTR_XMLNS_SCHEME
42
43/* #define DEBUG_RANGES */
44#ifdef DEBUG_RANGES
45#ifdef LIBXML_DEBUG_ENABLED
46#include <libxml/debugXML.h>
47#endif
48#endif
49
50#define TODO								\
51    xmlGenericError(xmlGenericErrorContext,				\
52	    "Unimplemented block at %s:%d\n",				\
53            __FILE__, __LINE__);
54
55#define STRANGE							\
56    xmlGenericError(xmlGenericErrorContext,				\
57	    "Internal error at %s:%d\n",				\
58            __FILE__, __LINE__);
59
60/************************************************************************
61 *									*
62 *		Some factorized error routines				*
63 *									*
64 ************************************************************************/
65
66/**
67 * xmlXPtrErrMemory:
68 * @extra:  extra informations
69 *
70 * Handle a redefinition of attribute error
71 */
72static void
73xmlXPtrErrMemory(const char *extra)
74{
75    __xmlRaiseError(NULL, NULL, NULL, NULL, NULL, XML_FROM_XPOINTER,
76		    XML_ERR_NO_MEMORY, XML_ERR_ERROR, NULL, 0, extra,
77		    NULL, NULL, 0, 0,
78		    "Memory allocation failed : %s\n", extra);
79}
80
81/**
82 * xmlXPtrErr:
83 * @ctxt:  an XPTR evaluation context
84 * @extra:  extra informations
85 *
86 * Handle a redefinition of attribute error
87 */
88static void
89xmlXPtrErr(xmlXPathParserContextPtr ctxt, int error,
90           const char * msg, const xmlChar *extra)
91{
92    if (ctxt != NULL)
93        ctxt->error = error;
94    if ((ctxt == NULL) || (ctxt->context == NULL)) {
95	__xmlRaiseError(NULL, NULL, NULL,
96			NULL, NULL, XML_FROM_XPOINTER, error,
97			XML_ERR_ERROR, NULL, 0,
98			(const char *) extra, NULL, NULL, 0, 0,
99			msg, extra);
100	return;
101    }
102    ctxt->context->lastError.domain = XML_FROM_XPOINTER;
103    ctxt->context->lastError.code = error;
104    ctxt->context->lastError.level = XML_ERR_ERROR;
105    ctxt->context->lastError.str1 = (char *) xmlStrdup(ctxt->base);
106    ctxt->context->lastError.int1 = ctxt->cur - ctxt->base;
107    ctxt->context->lastError.node = ctxt->context->debugNode;
108    if (ctxt->context->error != NULL) {
109	ctxt->context->error(ctxt->context->userData,
110	                     &ctxt->context->lastError);
111    } else {
112	__xmlRaiseError(NULL, NULL, NULL,
113			NULL, ctxt->context->debugNode, XML_FROM_XPOINTER,
114			error, XML_ERR_ERROR, NULL, 0,
115			(const char *) extra, (const char *) ctxt->base, NULL,
116			ctxt->cur - ctxt->base, 0,
117			msg, extra);
118    }
119}
120
121/************************************************************************
122 *									*
123 *		A few helper functions for child sequences		*
124 *									*
125 ************************************************************************/
126/* xmlXPtrAdvanceNode is a private function, but used by xinclude.c */
127xmlNodePtr xmlXPtrAdvanceNode(xmlNodePtr cur, int *level);
128/**
129 * xmlXPtrGetArity:
130 * @cur:  the node
131 *
132 * Returns the number of child for an element, -1 in case of error
133 */
134static int
135xmlXPtrGetArity(xmlNodePtr cur) {
136    int i;
137    if ((cur == NULL) || (cur->type == XML_NAMESPACE_DECL))
138	return(-1);
139    cur = cur->children;
140    for (i = 0;cur != NULL;cur = cur->next) {
141	if ((cur->type == XML_ELEMENT_NODE) ||
142	    (cur->type == XML_DOCUMENT_NODE) ||
143	    (cur->type == XML_HTML_DOCUMENT_NODE)) {
144	    i++;
145	}
146    }
147    return(i);
148}
149
150/**
151 * xmlXPtrGetIndex:
152 * @cur:  the node
153 *
154 * Returns the index of the node in its parent children list, -1
155 *         in case of error
156 */
157static int
158xmlXPtrGetIndex(xmlNodePtr cur) {
159    int i;
160    if ((cur == NULL) || (cur->type == XML_NAMESPACE_DECL))
161	return(-1);
162    for (i = 1;cur != NULL;cur = cur->prev) {
163	if ((cur->type == XML_ELEMENT_NODE) ||
164	    (cur->type == XML_DOCUMENT_NODE) ||
165	    (cur->type == XML_HTML_DOCUMENT_NODE)) {
166	    i++;
167	}
168    }
169    return(i);
170}
171
172/**
173 * xmlXPtrGetNthChild:
174 * @cur:  the node
175 * @no:  the child number
176 *
177 * Returns the @no'th element child of @cur or NULL
178 */
179static xmlNodePtr
180xmlXPtrGetNthChild(xmlNodePtr cur, int no) {
181    int i;
182    if ((cur == NULL) || (cur->type == XML_NAMESPACE_DECL))
183	return(cur);
184    cur = cur->children;
185    for (i = 0;i <= no;cur = cur->next) {
186	if (cur == NULL)
187	    return(cur);
188	if ((cur->type == XML_ELEMENT_NODE) ||
189	    (cur->type == XML_DOCUMENT_NODE) ||
190	    (cur->type == XML_HTML_DOCUMENT_NODE)) {
191	    i++;
192	    if (i == no)
193		break;
194	}
195    }
196    return(cur);
197}
198
199/************************************************************************
200 *									*
201 *		Handling of XPointer specific types			*
202 *									*
203 ************************************************************************/
204
205/**
206 * xmlXPtrCmpPoints:
207 * @node1:  the first node
208 * @index1:  the first index
209 * @node2:  the second node
210 * @index2:  the second index
211 *
212 * Compare two points w.r.t document order
213 *
214 * Returns -2 in case of error 1 if first point < second point, 0 if
215 *         that's the same point, -1 otherwise
216 */
217static int
218xmlXPtrCmpPoints(xmlNodePtr node1, int index1, xmlNodePtr node2, int index2) {
219    if ((node1 == NULL) || (node2 == NULL))
220	return(-2);
221    /*
222     * a couple of optimizations which will avoid computations in most cases
223     */
224    if (node1 == node2) {
225	if (index1 < index2)
226	    return(1);
227	if (index1 > index2)
228	    return(-1);
229	return(0);
230    }
231    return(xmlXPathCmpNodes(node1, node2));
232}
233
234/**
235 * xmlXPtrNewPoint:
236 * @node:  the xmlNodePtr
237 * @indx:  the indx within the node
238 *
239 * Create a new xmlXPathObjectPtr of type point
240 *
241 * Returns the newly created object.
242 */
243static xmlXPathObjectPtr
244xmlXPtrNewPoint(xmlNodePtr node, int indx) {
245    xmlXPathObjectPtr ret;
246
247    if (node == NULL)
248	return(NULL);
249    if (indx < 0)
250	return(NULL);
251
252    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
253    if (ret == NULL) {
254        xmlXPtrErrMemory("allocating point");
255	return(NULL);
256    }
257    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
258    ret->type = XPATH_POINT;
259    ret->user = (void *) node;
260    ret->index = indx;
261    return(ret);
262}
263
264/**
265 * xmlXPtrRangeCheckOrder:
266 * @range:  an object range
267 *
268 * Make sure the points in the range are in the right order
269 */
270static void
271xmlXPtrRangeCheckOrder(xmlXPathObjectPtr range) {
272    int tmp;
273    xmlNodePtr tmp2;
274    if (range == NULL)
275	return;
276    if (range->type != XPATH_RANGE)
277	return;
278    if (range->user2 == NULL)
279	return;
280    tmp = xmlXPtrCmpPoints(range->user, range->index,
281	                     range->user2, range->index2);
282    if (tmp == -1) {
283	tmp2 = range->user;
284	range->user = range->user2;
285	range->user2 = tmp2;
286	tmp = range->index;
287	range->index = range->index2;
288	range->index2 = tmp;
289    }
290}
291
292/**
293 * xmlXPtrRangesEqual:
294 * @range1:  the first range
295 * @range2:  the second range
296 *
297 * Compare two ranges
298 *
299 * Returns 1 if equal, 0 otherwise
300 */
301static int
302xmlXPtrRangesEqual(xmlXPathObjectPtr range1, xmlXPathObjectPtr range2) {
303    if (range1 == range2)
304	return(1);
305    if ((range1 == NULL) || (range2 == NULL))
306	return(0);
307    if (range1->type != range2->type)
308	return(0);
309    if (range1->type != XPATH_RANGE)
310	return(0);
311    if (range1->user != range2->user)
312	return(0);
313    if (range1->index != range2->index)
314	return(0);
315    if (range1->user2 != range2->user2)
316	return(0);
317    if (range1->index2 != range2->index2)
318	return(0);
319    return(1);
320}
321
322/**
323 * xmlXPtrNewRange:
324 * @start:  the starting node
325 * @startindex:  the start index
326 * @end:  the ending point
327 * @endindex:  the ending index
328 *
329 * Create a new xmlXPathObjectPtr of type range
330 *
331 * Returns the newly created object.
332 */
333xmlXPathObjectPtr
334xmlXPtrNewRange(xmlNodePtr start, int startindex,
335	        xmlNodePtr end, int endindex) {
336    xmlXPathObjectPtr ret;
337
338    if (start == NULL)
339	return(NULL);
340    if (end == NULL)
341	return(NULL);
342    if (startindex < 0)
343	return(NULL);
344    if (endindex < 0)
345	return(NULL);
346
347    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
348    if (ret == NULL) {
349        xmlXPtrErrMemory("allocating range");
350	return(NULL);
351    }
352    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
353    ret->type = XPATH_RANGE;
354    ret->user = start;
355    ret->index = startindex;
356    ret->user2 = end;
357    ret->index2 = endindex;
358    xmlXPtrRangeCheckOrder(ret);
359    return(ret);
360}
361
362/**
363 * xmlXPtrNewRangePoints:
364 * @start:  the starting point
365 * @end:  the ending point
366 *
367 * Create a new xmlXPathObjectPtr of type range using 2 Points
368 *
369 * Returns the newly created object.
370 */
371xmlXPathObjectPtr
372xmlXPtrNewRangePoints(xmlXPathObjectPtr start, xmlXPathObjectPtr end) {
373    xmlXPathObjectPtr ret;
374
375    if (start == NULL)
376	return(NULL);
377    if (end == NULL)
378	return(NULL);
379    if (start->type != XPATH_POINT)
380	return(NULL);
381    if (end->type != XPATH_POINT)
382	return(NULL);
383
384    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
385    if (ret == NULL) {
386        xmlXPtrErrMemory("allocating range");
387	return(NULL);
388    }
389    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
390    ret->type = XPATH_RANGE;
391    ret->user = start->user;
392    ret->index = start->index;
393    ret->user2 = end->user;
394    ret->index2 = end->index;
395    xmlXPtrRangeCheckOrder(ret);
396    return(ret);
397}
398
399/**
400 * xmlXPtrNewRangePointNode:
401 * @start:  the starting point
402 * @end:  the ending node
403 *
404 * Create a new xmlXPathObjectPtr of type range from a point to a node
405 *
406 * Returns the newly created object.
407 */
408xmlXPathObjectPtr
409xmlXPtrNewRangePointNode(xmlXPathObjectPtr start, xmlNodePtr end) {
410    xmlXPathObjectPtr ret;
411
412    if (start == NULL)
413	return(NULL);
414    if (end == NULL)
415	return(NULL);
416    if (start->type != XPATH_POINT)
417	return(NULL);
418
419    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
420    if (ret == NULL) {
421        xmlXPtrErrMemory("allocating range");
422	return(NULL);
423    }
424    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
425    ret->type = XPATH_RANGE;
426    ret->user = start->user;
427    ret->index = start->index;
428    ret->user2 = end;
429    ret->index2 = -1;
430    xmlXPtrRangeCheckOrder(ret);
431    return(ret);
432}
433
434/**
435 * xmlXPtrNewRangeNodePoint:
436 * @start:  the starting node
437 * @end:  the ending point
438 *
439 * Create a new xmlXPathObjectPtr of type range from a node to a point
440 *
441 * Returns the newly created object.
442 */
443xmlXPathObjectPtr
444xmlXPtrNewRangeNodePoint(xmlNodePtr start, xmlXPathObjectPtr end) {
445    xmlXPathObjectPtr ret;
446
447    if (start == NULL)
448	return(NULL);
449    if (end == NULL)
450	return(NULL);
451    if (start->type != XPATH_POINT)
452	return(NULL);
453    if (end->type != XPATH_POINT)
454	return(NULL);
455
456    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
457    if (ret == NULL) {
458        xmlXPtrErrMemory("allocating range");
459	return(NULL);
460    }
461    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
462    ret->type = XPATH_RANGE;
463    ret->user = start;
464    ret->index = -1;
465    ret->user2 = end->user;
466    ret->index2 = end->index;
467    xmlXPtrRangeCheckOrder(ret);
468    return(ret);
469}
470
471/**
472 * xmlXPtrNewRangeNodes:
473 * @start:  the starting node
474 * @end:  the ending node
475 *
476 * Create a new xmlXPathObjectPtr of type range using 2 nodes
477 *
478 * Returns the newly created object.
479 */
480xmlXPathObjectPtr
481xmlXPtrNewRangeNodes(xmlNodePtr start, xmlNodePtr end) {
482    xmlXPathObjectPtr ret;
483
484    if (start == NULL)
485	return(NULL);
486    if (end == NULL)
487	return(NULL);
488
489    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
490    if (ret == NULL) {
491        xmlXPtrErrMemory("allocating range");
492	return(NULL);
493    }
494    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
495    ret->type = XPATH_RANGE;
496    ret->user = start;
497    ret->index = -1;
498    ret->user2 = end;
499    ret->index2 = -1;
500    xmlXPtrRangeCheckOrder(ret);
501    return(ret);
502}
503
504/**
505 * xmlXPtrNewCollapsedRange:
506 * @start:  the starting and ending node
507 *
508 * Create a new xmlXPathObjectPtr of type range using a single nodes
509 *
510 * Returns the newly created object.
511 */
512xmlXPathObjectPtr
513xmlXPtrNewCollapsedRange(xmlNodePtr start) {
514    xmlXPathObjectPtr ret;
515
516    if (start == NULL)
517	return(NULL);
518
519    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
520    if (ret == NULL) {
521        xmlXPtrErrMemory("allocating range");
522	return(NULL);
523    }
524    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
525    ret->type = XPATH_RANGE;
526    ret->user = start;
527    ret->index = -1;
528    ret->user2 = NULL;
529    ret->index2 = -1;
530    return(ret);
531}
532
533/**
534 * xmlXPtrNewRangeNodeObject:
535 * @start:  the starting node
536 * @end:  the ending object
537 *
538 * Create a new xmlXPathObjectPtr of type range from a not to an object
539 *
540 * Returns the newly created object.
541 */
542xmlXPathObjectPtr
543xmlXPtrNewRangeNodeObject(xmlNodePtr start, xmlXPathObjectPtr end) {
544    xmlXPathObjectPtr ret;
545
546    if (start == NULL)
547	return(NULL);
548    if (end == NULL)
549	return(NULL);
550    switch (end->type) {
551	case XPATH_POINT:
552	case XPATH_RANGE:
553	    break;
554	case XPATH_NODESET:
555	    /*
556	     * Empty set ...
557	     */
558	    if (end->nodesetval->nodeNr <= 0)
559		return(NULL);
560	    break;
561	default:
562	    /* TODO */
563	    return(NULL);
564    }
565
566    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
567    if (ret == NULL) {
568        xmlXPtrErrMemory("allocating range");
569	return(NULL);
570    }
571    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
572    ret->type = XPATH_RANGE;
573    ret->user = start;
574    ret->index = -1;
575    switch (end->type) {
576	case XPATH_POINT:
577	    ret->user2 = end->user;
578	    ret->index2 = end->index;
579	    break;
580	case XPATH_RANGE:
581	    ret->user2 = end->user2;
582	    ret->index2 = end->index2;
583	    break;
584	case XPATH_NODESET: {
585	    ret->user2 = end->nodesetval->nodeTab[end->nodesetval->nodeNr - 1];
586	    ret->index2 = -1;
587	    break;
588	}
589	default:
590	    STRANGE
591	    return(NULL);
592    }
593    xmlXPtrRangeCheckOrder(ret);
594    return(ret);
595}
596
597#define XML_RANGESET_DEFAULT	10
598
599/**
600 * xmlXPtrLocationSetCreate:
601 * @val:  an initial xmlXPathObjectPtr, or NULL
602 *
603 * Create a new xmlLocationSetPtr of type double and of value @val
604 *
605 * Returns the newly created object.
606 */
607xmlLocationSetPtr
608xmlXPtrLocationSetCreate(xmlXPathObjectPtr val) {
609    xmlLocationSetPtr ret;
610
611    ret = (xmlLocationSetPtr) xmlMalloc(sizeof(xmlLocationSet));
612    if (ret == NULL) {
613        xmlXPtrErrMemory("allocating locationset");
614	return(NULL);
615    }
616    memset(ret, 0 , (size_t) sizeof(xmlLocationSet));
617    if (val != NULL) {
618        ret->locTab = (xmlXPathObjectPtr *) xmlMalloc(XML_RANGESET_DEFAULT *
619					     sizeof(xmlXPathObjectPtr));
620	if (ret->locTab == NULL) {
621	    xmlXPtrErrMemory("allocating locationset");
622	    xmlFree(ret);
623	    return(NULL);
624	}
625	memset(ret->locTab, 0 ,
626	       XML_RANGESET_DEFAULT * (size_t) sizeof(xmlXPathObjectPtr));
627        ret->locMax = XML_RANGESET_DEFAULT;
628	ret->locTab[ret->locNr++] = val;
629    }
630    return(ret);
631}
632
633/**
634 * xmlXPtrLocationSetAdd:
635 * @cur:  the initial range set
636 * @val:  a new xmlXPathObjectPtr
637 *
638 * add a new xmlXPathObjectPtr to an existing LocationSet
639 * If the location already exist in the set @val is freed.
640 */
641void
642xmlXPtrLocationSetAdd(xmlLocationSetPtr cur, xmlXPathObjectPtr val) {
643    int i;
644
645    if ((cur == NULL) || (val == NULL)) return;
646
647    /*
648     * check against doublons
649     */
650    for (i = 0;i < cur->locNr;i++) {
651	if (xmlXPtrRangesEqual(cur->locTab[i], val)) {
652	    xmlXPathFreeObject(val);
653	    return;
654	}
655    }
656
657    /*
658     * grow the locTab if needed
659     */
660    if (cur->locMax == 0) {
661        cur->locTab = (xmlXPathObjectPtr *) xmlMalloc(XML_RANGESET_DEFAULT *
662					     sizeof(xmlXPathObjectPtr));
663	if (cur->locTab == NULL) {
664	    xmlXPtrErrMemory("adding location to set");
665	    return;
666	}
667	memset(cur->locTab, 0 ,
668	       XML_RANGESET_DEFAULT * (size_t) sizeof(xmlXPathObjectPtr));
669        cur->locMax = XML_RANGESET_DEFAULT;
670    } else if (cur->locNr == cur->locMax) {
671        xmlXPathObjectPtr *temp;
672
673        cur->locMax *= 2;
674	temp = (xmlXPathObjectPtr *) xmlRealloc(cur->locTab, cur->locMax *
675				      sizeof(xmlXPathObjectPtr));
676	if (temp == NULL) {
677	    xmlXPtrErrMemory("adding location to set");
678	    return;
679	}
680	cur->locTab = temp;
681    }
682    cur->locTab[cur->locNr++] = val;
683}
684
685/**
686 * xmlXPtrLocationSetMerge:
687 * @val1:  the first LocationSet
688 * @val2:  the second LocationSet
689 *
690 * Merges two rangesets, all ranges from @val2 are added to @val1
691 *
692 * Returns val1 once extended or NULL in case of error.
693 */
694xmlLocationSetPtr
695xmlXPtrLocationSetMerge(xmlLocationSetPtr val1, xmlLocationSetPtr val2) {
696    int i;
697
698    if (val1 == NULL) return(NULL);
699    if (val2 == NULL) return(val1);
700
701    /*
702     * !!!!! this can be optimized a lot, knowing that both
703     *       val1 and val2 already have unicity of their values.
704     */
705
706    for (i = 0;i < val2->locNr;i++)
707        xmlXPtrLocationSetAdd(val1, val2->locTab[i]);
708
709    return(val1);
710}
711
712/**
713 * xmlXPtrLocationSetDel:
714 * @cur:  the initial range set
715 * @val:  an xmlXPathObjectPtr
716 *
717 * Removes an xmlXPathObjectPtr from an existing LocationSet
718 */
719void
720xmlXPtrLocationSetDel(xmlLocationSetPtr cur, xmlXPathObjectPtr val) {
721    int i;
722
723    if (cur == NULL) return;
724    if (val == NULL) return;
725
726    /*
727     * check against doublons
728     */
729    for (i = 0;i < cur->locNr;i++)
730        if (cur->locTab[i] == val) break;
731
732    if (i >= cur->locNr) {
733#ifdef DEBUG
734        xmlGenericError(xmlGenericErrorContext,
735	        "xmlXPtrLocationSetDel: Range wasn't found in RangeList\n");
736#endif
737        return;
738    }
739    cur->locNr--;
740    for (;i < cur->locNr;i++)
741        cur->locTab[i] = cur->locTab[i + 1];
742    cur->locTab[cur->locNr] = NULL;
743}
744
745/**
746 * xmlXPtrLocationSetRemove:
747 * @cur:  the initial range set
748 * @val:  the index to remove
749 *
750 * Removes an entry from an existing LocationSet list.
751 */
752void
753xmlXPtrLocationSetRemove(xmlLocationSetPtr cur, int val) {
754    if (cur == NULL) return;
755    if (val >= cur->locNr) return;
756    cur->locNr--;
757    for (;val < cur->locNr;val++)
758        cur->locTab[val] = cur->locTab[val + 1];
759    cur->locTab[cur->locNr] = NULL;
760}
761
762/**
763 * xmlXPtrFreeLocationSet:
764 * @obj:  the xmlLocationSetPtr to free
765 *
766 * Free the LocationSet compound (not the actual ranges !).
767 */
768void
769xmlXPtrFreeLocationSet(xmlLocationSetPtr obj) {
770    int i;
771
772    if (obj == NULL) return;
773    if (obj->locTab != NULL) {
774	for (i = 0;i < obj->locNr; i++) {
775            xmlXPathFreeObject(obj->locTab[i]);
776	}
777	xmlFree(obj->locTab);
778    }
779    xmlFree(obj);
780}
781
782/**
783 * xmlXPtrNewLocationSetNodes:
784 * @start:  the start NodePtr value
785 * @end:  the end NodePtr value or NULL
786 *
787 * Create a new xmlXPathObjectPtr of type LocationSet and initialize
788 * it with the single range made of the two nodes @start and @end
789 *
790 * Returns the newly created object.
791 */
792xmlXPathObjectPtr
793xmlXPtrNewLocationSetNodes(xmlNodePtr start, xmlNodePtr end) {
794    xmlXPathObjectPtr ret;
795
796    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
797    if (ret == NULL) {
798        xmlXPtrErrMemory("allocating locationset");
799	return(NULL);
800    }
801    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
802    ret->type = XPATH_LOCATIONSET;
803    if (end == NULL)
804	ret->user = xmlXPtrLocationSetCreate(xmlXPtrNewCollapsedRange(start));
805    else
806	ret->user = xmlXPtrLocationSetCreate(xmlXPtrNewRangeNodes(start,end));
807    return(ret);
808}
809
810/**
811 * xmlXPtrNewLocationSetNodeSet:
812 * @set:  a node set
813 *
814 * Create a new xmlXPathObjectPtr of type LocationSet and initialize
815 * it with all the nodes from @set
816 *
817 * Returns the newly created object.
818 */
819xmlXPathObjectPtr
820xmlXPtrNewLocationSetNodeSet(xmlNodeSetPtr set) {
821    xmlXPathObjectPtr ret;
822
823    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
824    if (ret == NULL) {
825        xmlXPtrErrMemory("allocating locationset");
826	return(NULL);
827    }
828    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
829    ret->type = XPATH_LOCATIONSET;
830    if (set != NULL) {
831	int i;
832	xmlLocationSetPtr newset;
833
834	newset = xmlXPtrLocationSetCreate(NULL);
835	if (newset == NULL)
836	    return(ret);
837
838	for (i = 0;i < set->nodeNr;i++)
839	    xmlXPtrLocationSetAdd(newset,
840		        xmlXPtrNewCollapsedRange(set->nodeTab[i]));
841
842	ret->user = (void *) newset;
843    }
844    return(ret);
845}
846
847/**
848 * xmlXPtrWrapLocationSet:
849 * @val:  the LocationSet value
850 *
851 * Wrap the LocationSet @val in a new xmlXPathObjectPtr
852 *
853 * Returns the newly created object.
854 */
855xmlXPathObjectPtr
856xmlXPtrWrapLocationSet(xmlLocationSetPtr val) {
857    xmlXPathObjectPtr ret;
858
859    ret = (xmlXPathObjectPtr) xmlMalloc(sizeof(xmlXPathObject));
860    if (ret == NULL) {
861        xmlXPtrErrMemory("allocating locationset");
862	return(NULL);
863    }
864    memset(ret, 0 , (size_t) sizeof(xmlXPathObject));
865    ret->type = XPATH_LOCATIONSET;
866    ret->user = (void *) val;
867    return(ret);
868}
869
870/************************************************************************
871 *									*
872 *			The parser					*
873 *									*
874 ************************************************************************/
875
876static void xmlXPtrEvalChildSeq(xmlXPathParserContextPtr ctxt, xmlChar *name);
877
878/*
879 * Macros for accessing the content. Those should be used only by the parser,
880 * and not exported.
881 *
882 * Dirty macros, i.e. one need to make assumption on the context to use them
883 *
884 *   CUR_PTR return the current pointer to the xmlChar to be parsed.
885 *   CUR     returns the current xmlChar value, i.e. a 8 bit value
886 *           in ISO-Latin or UTF-8.
887 *           This should be used internally by the parser
888 *           only to compare to ASCII values otherwise it would break when
889 *           running with UTF-8 encoding.
890 *   NXT(n)  returns the n'th next xmlChar. Same as CUR is should be used only
891 *           to compare on ASCII based substring.
892 *   SKIP(n) Skip n xmlChar, and must also be used only to skip ASCII defined
893 *           strings within the parser.
894 *   CURRENT Returns the current char value, with the full decoding of
895 *           UTF-8 if we are using this mode. It returns an int.
896 *   NEXT    Skip to the next character, this does the proper decoding
897 *           in UTF-8 mode. It also pop-up unfinished entities on the fly.
898 *           It returns the pointer to the current xmlChar.
899 */
900
901#define CUR (*ctxt->cur)
902#define SKIP(val) ctxt->cur += (val)
903#define NXT(val) ctxt->cur[(val)]
904#define CUR_PTR ctxt->cur
905
906#define SKIP_BLANKS							\
907    while (IS_BLANK_CH(*(ctxt->cur))) NEXT
908
909#define CURRENT (*ctxt->cur)
910#define NEXT ((*ctxt->cur) ?  ctxt->cur++: ctxt->cur)
911
912/*
913 * xmlXPtrGetChildNo:
914 * @ctxt:  the XPointer Parser context
915 * @index:  the child number
916 *
917 * Move the current node of the nodeset on the stack to the
918 * given child if found
919 */
920static void
921xmlXPtrGetChildNo(xmlXPathParserContextPtr ctxt, int indx) {
922    xmlNodePtr cur = NULL;
923    xmlXPathObjectPtr obj;
924    xmlNodeSetPtr oldset;
925
926    CHECK_TYPE(XPATH_NODESET);
927    obj = valuePop(ctxt);
928    oldset = obj->nodesetval;
929    if ((indx <= 0) || (oldset == NULL) || (oldset->nodeNr != 1)) {
930	xmlXPathFreeObject(obj);
931	valuePush(ctxt, xmlXPathNewNodeSet(NULL));
932	return;
933    }
934    cur = xmlXPtrGetNthChild(oldset->nodeTab[0], indx);
935    if (cur == NULL) {
936	xmlXPathFreeObject(obj);
937	valuePush(ctxt, xmlXPathNewNodeSet(NULL));
938	return;
939    }
940    oldset->nodeTab[0] = cur;
941    valuePush(ctxt, obj);
942}
943
944/**
945 * xmlXPtrEvalXPtrPart:
946 * @ctxt:  the XPointer Parser context
947 * @name:  the preparsed Scheme for the XPtrPart
948 *
949 * XPtrPart ::= 'xpointer' '(' XPtrExpr ')'
950 *            | Scheme '(' SchemeSpecificExpr ')'
951 *
952 * Scheme   ::=  NCName - 'xpointer' [VC: Non-XPointer schemes]
953 *
954 * SchemeSpecificExpr ::= StringWithBalancedParens
955 *
956 * StringWithBalancedParens ::=
957 *              [^()]* ('(' StringWithBalancedParens ')' [^()]*)*
958 *              [VC: Parenthesis escaping]
959 *
960 * XPtrExpr ::= Expr [VC: Parenthesis escaping]
961 *
962 * VC: Parenthesis escaping:
963 *   The end of an XPointer part is signaled by the right parenthesis ")"
964 *   character that is balanced with the left parenthesis "(" character
965 *   that began the part. Any unbalanced parenthesis character inside the
966 *   expression, even within literals, must be escaped with a circumflex (^)
967 *   character preceding it. If the expression contains any literal
968 *   occurrences of the circumflex, each must be escaped with an additional
969 *   circumflex (that is, ^^). If the unescaped parentheses in the expression
970 *   are not balanced, a syntax error results.
971 *
972 * Parse and evaluate an XPtrPart. Basically it generates the unescaped
973 * string and if the scheme is 'xpointer' it will call the XPath interpreter.
974 *
975 * TODO: there is no new scheme registration mechanism
976 */
977
978static void
979xmlXPtrEvalXPtrPart(xmlXPathParserContextPtr ctxt, xmlChar *name) {
980    xmlChar *buffer, *cur;
981    int len;
982    int level;
983
984    if (name == NULL)
985    name = xmlXPathParseName(ctxt);
986    if (name == NULL)
987	XP_ERROR(XPATH_EXPR_ERROR);
988
989    if (CUR != '(')
990	XP_ERROR(XPATH_EXPR_ERROR);
991    NEXT;
992    level = 1;
993
994    len = xmlStrlen(ctxt->cur);
995    len++;
996    buffer = (xmlChar *) xmlMallocAtomic(len * sizeof (xmlChar));
997    if (buffer == NULL) {
998        xmlXPtrErrMemory("allocating buffer");
999	return;
1000    }
1001
1002    cur = buffer;
1003    while (CUR != 0) {
1004	if (CUR == ')') {
1005	    level--;
1006	    if (level == 0) {
1007		NEXT;
1008		break;
1009	    }
1010	} else if (CUR == '(') {
1011	    level++;
1012	} else if (CUR == '^') {
1013            if ((NXT(1) == ')') || (NXT(1) == '(') || (NXT(1) == '^')) {
1014                NEXT;
1015            }
1016	}
1017        *cur++ = CUR;
1018	NEXT;
1019    }
1020    *cur = 0;
1021
1022    if ((level != 0) && (CUR == 0)) {
1023	xmlFree(buffer);
1024	XP_ERROR(XPTR_SYNTAX_ERROR);
1025    }
1026
1027    if (xmlStrEqual(name, (xmlChar *) "xpointer")) {
1028	const xmlChar *left = CUR_PTR;
1029
1030	CUR_PTR = buffer;
1031	/*
1032	 * To evaluate an xpointer scheme element (4.3) we need:
1033	 *   context initialized to the root
1034	 *   context position initalized to 1
1035	 *   context size initialized to 1
1036	 */
1037	ctxt->context->node = (xmlNodePtr)ctxt->context->doc;
1038	ctxt->context->proximityPosition = 1;
1039	ctxt->context->contextSize = 1;
1040	xmlXPathEvalExpr(ctxt);
1041	CUR_PTR=left;
1042    } else if (xmlStrEqual(name, (xmlChar *) "element")) {
1043	const xmlChar *left = CUR_PTR;
1044	xmlChar *name2;
1045
1046	CUR_PTR = buffer;
1047	if (buffer[0] == '/') {
1048	    xmlXPathRoot(ctxt);
1049	    xmlXPtrEvalChildSeq(ctxt, NULL);
1050	} else {
1051	    name2 = xmlXPathParseName(ctxt);
1052	    if (name2 == NULL) {
1053		CUR_PTR = left;
1054		xmlFree(buffer);
1055		XP_ERROR(XPATH_EXPR_ERROR);
1056	    }
1057	    xmlXPtrEvalChildSeq(ctxt, name2);
1058	}
1059	CUR_PTR = left;
1060#ifdef XPTR_XMLNS_SCHEME
1061    } else if (xmlStrEqual(name, (xmlChar *) "xmlns")) {
1062	const xmlChar *left = CUR_PTR;
1063	xmlChar *prefix;
1064	xmlChar *URI;
1065	xmlURIPtr value;
1066
1067	CUR_PTR = buffer;
1068        prefix = xmlXPathParseNCName(ctxt);
1069	if (prefix == NULL) {
1070	    xmlFree(buffer);
1071	    xmlFree(name);
1072	    XP_ERROR(XPTR_SYNTAX_ERROR);
1073	}
1074	SKIP_BLANKS;
1075	if (CUR != '=') {
1076	    xmlFree(prefix);
1077	    xmlFree(buffer);
1078	    xmlFree(name);
1079	    XP_ERROR(XPTR_SYNTAX_ERROR);
1080	}
1081	NEXT;
1082	SKIP_BLANKS;
1083	/* @@ check escaping in the XPointer WD */
1084
1085	value = xmlParseURI((const char *)ctxt->cur);
1086	if (value == NULL) {
1087	    xmlFree(prefix);
1088	    xmlFree(buffer);
1089	    xmlFree(name);
1090	    XP_ERROR(XPTR_SYNTAX_ERROR);
1091	}
1092	URI = xmlSaveUri(value);
1093	xmlFreeURI(value);
1094	if (URI == NULL) {
1095	    xmlFree(prefix);
1096	    xmlFree(buffer);
1097	    xmlFree(name);
1098	    XP_ERROR(XPATH_MEMORY_ERROR);
1099	}
1100
1101	xmlXPathRegisterNs(ctxt->context, prefix, URI);
1102	CUR_PTR = left;
1103	xmlFree(URI);
1104	xmlFree(prefix);
1105#endif /* XPTR_XMLNS_SCHEME */
1106    } else {
1107        xmlXPtrErr(ctxt, XML_XPTR_UNKNOWN_SCHEME,
1108		   "unsupported scheme '%s'\n", name);
1109    }
1110    xmlFree(buffer);
1111    xmlFree(name);
1112}
1113
1114/**
1115 * xmlXPtrEvalFullXPtr:
1116 * @ctxt:  the XPointer Parser context
1117 * @name:  the preparsed Scheme for the first XPtrPart
1118 *
1119 * FullXPtr ::= XPtrPart (S? XPtrPart)*
1120 *
1121 * As the specs says:
1122 * -----------
1123 * When multiple XPtrParts are provided, they must be evaluated in
1124 * left-to-right order. If evaluation of one part fails, the nexti
1125 * is evaluated. The following conditions cause XPointer part failure:
1126 *
1127 * - An unknown scheme
1128 * - A scheme that does not locate any sub-resource present in the resource
1129 * - A scheme that is not applicable to the media type of the resource
1130 *
1131 * The XPointer application must consume a failed XPointer part and
1132 * attempt to evaluate the next one, if any. The result of the first
1133 * XPointer part whose evaluation succeeds is taken to be the fragment
1134 * located by the XPointer as a whole. If all the parts fail, the result
1135 * for the XPointer as a whole is a sub-resource error.
1136 * -----------
1137 *
1138 * Parse and evaluate a Full XPtr i.e. possibly a cascade of XPath based
1139 * expressions or other schemes.
1140 */
1141static void
1142xmlXPtrEvalFullXPtr(xmlXPathParserContextPtr ctxt, xmlChar *name) {
1143    if (name == NULL)
1144    name = xmlXPathParseName(ctxt);
1145    if (name == NULL)
1146	XP_ERROR(XPATH_EXPR_ERROR);
1147    while (name != NULL) {
1148	ctxt->error = XPATH_EXPRESSION_OK;
1149	xmlXPtrEvalXPtrPart(ctxt, name);
1150
1151	/* in case of syntax error, break here */
1152	if ((ctxt->error != XPATH_EXPRESSION_OK) &&
1153            (ctxt->error != XML_XPTR_UNKNOWN_SCHEME))
1154	    return;
1155
1156	/*
1157	 * If the returned value is a non-empty nodeset
1158	 * or location set, return here.
1159	 */
1160	if (ctxt->value != NULL) {
1161	    xmlXPathObjectPtr obj = ctxt->value;
1162
1163	    switch (obj->type) {
1164		case XPATH_LOCATIONSET: {
1165		    xmlLocationSetPtr loc = ctxt->value->user;
1166		    if ((loc != NULL) && (loc->locNr > 0))
1167			return;
1168		    break;
1169		}
1170		case XPATH_NODESET: {
1171		    xmlNodeSetPtr loc = ctxt->value->nodesetval;
1172		    if ((loc != NULL) && (loc->nodeNr > 0))
1173			return;
1174		    break;
1175		}
1176		default:
1177		    break;
1178	    }
1179
1180	    /*
1181	     * Evaluating to improper values is equivalent to
1182	     * a sub-resource error, clean-up the stack
1183	     */
1184	    do {
1185		obj = valuePop(ctxt);
1186		if (obj != NULL) {
1187		    xmlXPathFreeObject(obj);
1188		}
1189	    } while (obj != NULL);
1190	}
1191
1192	/*
1193	 * Is there another XPointer part.
1194	 */
1195	SKIP_BLANKS;
1196	name = xmlXPathParseName(ctxt);
1197    }
1198}
1199
1200/**
1201 * xmlXPtrEvalChildSeq:
1202 * @ctxt:  the XPointer Parser context
1203 * @name:  a possible ID name of the child sequence
1204 *
1205 *  ChildSeq ::= '/1' ('/' [0-9]*)*
1206 *             | Name ('/' [0-9]*)+
1207 *
1208 * Parse and evaluate a Child Sequence. This routine also handle the
1209 * case of a Bare Name used to get a document ID.
1210 */
1211static void
1212xmlXPtrEvalChildSeq(xmlXPathParserContextPtr ctxt, xmlChar *name) {
1213    /*
1214     * XPointer don't allow by syntax to address in mutirooted trees
1215     * this might prove useful in some cases, warn about it.
1216     */
1217    if ((name == NULL) && (CUR == '/') && (NXT(1) != '1')) {
1218        xmlXPtrErr(ctxt, XML_XPTR_CHILDSEQ_START,
1219		   "warning: ChildSeq not starting by /1\n", NULL);
1220    }
1221
1222    if (name != NULL) {
1223	valuePush(ctxt, xmlXPathNewString(name));
1224	xmlFree(name);
1225	xmlXPathIdFunction(ctxt, 1);
1226	CHECK_ERROR;
1227    }
1228
1229    while (CUR == '/') {
1230	int child = 0;
1231	NEXT;
1232
1233	while ((CUR >= '0') && (CUR <= '9')) {
1234	    child = child * 10 + (CUR - '0');
1235	    NEXT;
1236	}
1237	xmlXPtrGetChildNo(ctxt, child);
1238    }
1239}
1240
1241
1242/**
1243 * xmlXPtrEvalXPointer:
1244 * @ctxt:  the XPointer Parser context
1245 *
1246 *  XPointer ::= Name
1247 *             | ChildSeq
1248 *             | FullXPtr
1249 *
1250 * Parse and evaluate an XPointer
1251 */
1252static void
1253xmlXPtrEvalXPointer(xmlXPathParserContextPtr ctxt) {
1254    if (ctxt->valueTab == NULL) {
1255	/* Allocate the value stack */
1256	ctxt->valueTab = (xmlXPathObjectPtr *)
1257			 xmlMalloc(10 * sizeof(xmlXPathObjectPtr));
1258	if (ctxt->valueTab == NULL) {
1259	    xmlXPtrErrMemory("allocating evaluation context");
1260	    return;
1261	}
1262	ctxt->valueNr = 0;
1263	ctxt->valueMax = 10;
1264	ctxt->value = NULL;
1265	ctxt->valueFrame = 0;
1266    }
1267    SKIP_BLANKS;
1268    if (CUR == '/') {
1269	xmlXPathRoot(ctxt);
1270        xmlXPtrEvalChildSeq(ctxt, NULL);
1271    } else {
1272	xmlChar *name;
1273
1274	name = xmlXPathParseName(ctxt);
1275	if (name == NULL)
1276	    XP_ERROR(XPATH_EXPR_ERROR);
1277	if (CUR == '(') {
1278	    xmlXPtrEvalFullXPtr(ctxt, name);
1279	    /* Short evaluation */
1280	    return;
1281	} else {
1282	    /* this handle both Bare Names and Child Sequences */
1283	    xmlXPtrEvalChildSeq(ctxt, name);
1284	}
1285    }
1286    SKIP_BLANKS;
1287    if (CUR != 0)
1288	XP_ERROR(XPATH_EXPR_ERROR);
1289}
1290
1291
1292/************************************************************************
1293 *									*
1294 *			General routines				*
1295 *									*
1296 ************************************************************************/
1297
1298static
1299void xmlXPtrStringRangeFunction(xmlXPathParserContextPtr ctxt, int nargs);
1300static
1301void xmlXPtrStartPointFunction(xmlXPathParserContextPtr ctxt, int nargs);
1302static
1303void xmlXPtrEndPointFunction(xmlXPathParserContextPtr ctxt, int nargs);
1304static
1305void xmlXPtrHereFunction(xmlXPathParserContextPtr ctxt, int nargs);
1306static
1307void xmlXPtrOriginFunction(xmlXPathParserContextPtr ctxt, int nargs);
1308static
1309void xmlXPtrRangeInsideFunction(xmlXPathParserContextPtr ctxt, int nargs);
1310static
1311void xmlXPtrRangeFunction(xmlXPathParserContextPtr ctxt, int nargs);
1312
1313/**
1314 * xmlXPtrNewContext:
1315 * @doc:  the XML document
1316 * @here:  the node that directly contains the XPointer being evaluated or NULL
1317 * @origin:  the element from which a user or program initiated traversal of
1318 *           the link, or NULL.
1319 *
1320 * Create a new XPointer context
1321 *
1322 * Returns the xmlXPathContext just allocated.
1323 */
1324xmlXPathContextPtr
1325xmlXPtrNewContext(xmlDocPtr doc, xmlNodePtr here, xmlNodePtr origin) {
1326    xmlXPathContextPtr ret;
1327
1328    ret = xmlXPathNewContext(doc);
1329    if (ret == NULL)
1330	return(ret);
1331    ret->xptr = 1;
1332    ret->here = here;
1333    ret->origin = origin;
1334
1335    xmlXPathRegisterFunc(ret, (xmlChar *)"range-to",
1336	                 xmlXPtrRangeToFunction);
1337    xmlXPathRegisterFunc(ret, (xmlChar *)"range",
1338	                 xmlXPtrRangeFunction);
1339    xmlXPathRegisterFunc(ret, (xmlChar *)"range-inside",
1340	                 xmlXPtrRangeInsideFunction);
1341    xmlXPathRegisterFunc(ret, (xmlChar *)"string-range",
1342	                 xmlXPtrStringRangeFunction);
1343    xmlXPathRegisterFunc(ret, (xmlChar *)"start-point",
1344	                 xmlXPtrStartPointFunction);
1345    xmlXPathRegisterFunc(ret, (xmlChar *)"end-point",
1346	                 xmlXPtrEndPointFunction);
1347    xmlXPathRegisterFunc(ret, (xmlChar *)"here",
1348	                 xmlXPtrHereFunction);
1349    xmlXPathRegisterFunc(ret, (xmlChar *)" origin",
1350	                 xmlXPtrOriginFunction);
1351
1352    return(ret);
1353}
1354
1355/**
1356 * xmlXPtrEval:
1357 * @str:  the XPointer expression
1358 * @ctx:  the XPointer context
1359 *
1360 * Evaluate the XPath Location Path in the given context.
1361 *
1362 * Returns the xmlXPathObjectPtr resulting from the evaluation or NULL.
1363 *         the caller has to free the object.
1364 */
1365xmlXPathObjectPtr
1366xmlXPtrEval(const xmlChar *str, xmlXPathContextPtr ctx) {
1367    xmlXPathParserContextPtr ctxt;
1368    xmlXPathObjectPtr res = NULL, tmp;
1369    xmlXPathObjectPtr init = NULL;
1370    int stack = 0;
1371
1372    xmlXPathInit();
1373
1374    if ((ctx == NULL) || (str == NULL))
1375	return(NULL);
1376
1377    ctxt = xmlXPathNewParserContext(str, ctx);
1378    if (ctxt == NULL)
1379	return(NULL);
1380    ctxt->xptr = 1;
1381    xmlXPtrEvalXPointer(ctxt);
1382
1383    if ((ctxt->value != NULL) &&
1384	(ctxt->value->type != XPATH_NODESET) &&
1385	(ctxt->value->type != XPATH_LOCATIONSET)) {
1386        xmlXPtrErr(ctxt, XML_XPTR_EVAL_FAILED,
1387		"xmlXPtrEval: evaluation failed to return a node set\n",
1388		   NULL);
1389    } else {
1390	res = valuePop(ctxt);
1391    }
1392
1393    do {
1394        tmp = valuePop(ctxt);
1395	if (tmp != NULL) {
1396	    if (tmp != init) {
1397		if (tmp->type == XPATH_NODESET) {
1398		    /*
1399		     * Evaluation may push a root nodeset which is unused
1400		     */
1401		    xmlNodeSetPtr set;
1402		    set = tmp->nodesetval;
1403		    if ((set->nodeNr != 1) ||
1404			(set->nodeTab[0] != (xmlNodePtr) ctx->doc))
1405			stack++;
1406		} else
1407		    stack++;
1408	    }
1409	    xmlXPathFreeObject(tmp);
1410        }
1411    } while (tmp != NULL);
1412    if (stack != 0) {
1413        xmlXPtrErr(ctxt, XML_XPTR_EXTRA_OBJECTS,
1414		   "xmlXPtrEval: object(s) left on the eval stack\n",
1415		   NULL);
1416    }
1417    if (ctxt->error != XPATH_EXPRESSION_OK) {
1418	xmlXPathFreeObject(res);
1419	res = NULL;
1420    }
1421
1422    xmlXPathFreeParserContext(ctxt);
1423    return(res);
1424}
1425
1426/**
1427 * xmlXPtrBuildRangeNodeList:
1428 * @range:  a range object
1429 *
1430 * Build a node list tree copy of the range
1431 *
1432 * Returns an xmlNodePtr list or NULL.
1433 *         the caller has to free the node tree.
1434 */
1435static xmlNodePtr
1436xmlXPtrBuildRangeNodeList(xmlXPathObjectPtr range) {
1437    /* pointers to generated nodes */
1438    xmlNodePtr list = NULL, last = NULL, parent = NULL, tmp;
1439    /* pointers to traversal nodes */
1440    xmlNodePtr start, cur, end;
1441    int index1, index2;
1442
1443    if (range == NULL)
1444	return(NULL);
1445    if (range->type != XPATH_RANGE)
1446	return(NULL);
1447    start = (xmlNodePtr) range->user;
1448
1449    if ((start == NULL) || (start->type == XML_NAMESPACE_DECL))
1450	return(NULL);
1451    end = range->user2;
1452    if (end == NULL)
1453	return(xmlCopyNode(start, 1));
1454    if (end->type == XML_NAMESPACE_DECL)
1455        return(NULL);
1456
1457    cur = start;
1458    index1 = range->index;
1459    index2 = range->index2;
1460    while (cur != NULL) {
1461	if (cur == end) {
1462	    if (cur->type == XML_TEXT_NODE) {
1463		const xmlChar *content = cur->content;
1464		int len;
1465
1466		if (content == NULL) {
1467		    tmp = xmlNewTextLen(NULL, 0);
1468		} else {
1469		    len = index2;
1470		    if ((cur == start) && (index1 > 1)) {
1471			content += (index1 - 1);
1472			len -= (index1 - 1);
1473			index1 = 0;
1474		    } else {
1475			len = index2;
1476		    }
1477		    tmp = xmlNewTextLen(content, len);
1478		}
1479		/* single sub text node selection */
1480		if (list == NULL)
1481		    return(tmp);
1482		/* prune and return full set */
1483		if (last != NULL)
1484		    xmlAddNextSibling(last, tmp);
1485		else
1486		    xmlAddChild(parent, tmp);
1487		return(list);
1488	    } else {
1489		tmp = xmlCopyNode(cur, 0);
1490		if (list == NULL)
1491		    list = tmp;
1492		else {
1493		    if (last != NULL)
1494			xmlAddNextSibling(last, tmp);
1495		    else
1496			xmlAddChild(parent, tmp);
1497		}
1498		last = NULL;
1499		parent = tmp;
1500
1501		if (index2 > 1) {
1502		    end = xmlXPtrGetNthChild(cur, index2 - 1);
1503		    index2 = 0;
1504		}
1505		if ((cur == start) && (index1 > 1)) {
1506		    cur = xmlXPtrGetNthChild(cur, index1 - 1);
1507		    index1 = 0;
1508		} else {
1509		    cur = cur->children;
1510		}
1511		/*
1512		 * Now gather the remaining nodes from cur to end
1513		 */
1514		continue; /* while */
1515	    }
1516	} else if ((cur == start) &&
1517		   (list == NULL) /* looks superfluous but ... */ ) {
1518	    if ((cur->type == XML_TEXT_NODE) ||
1519		(cur->type == XML_CDATA_SECTION_NODE)) {
1520		const xmlChar *content = cur->content;
1521
1522		if (content == NULL) {
1523		    tmp = xmlNewTextLen(NULL, 0);
1524		} else {
1525		    if (index1 > 1) {
1526			content += (index1 - 1);
1527		    }
1528		    tmp = xmlNewText(content);
1529		}
1530		last = list = tmp;
1531	    } else {
1532		if ((cur == start) && (index1 > 1)) {
1533		    tmp = xmlCopyNode(cur, 0);
1534		    list = tmp;
1535		    parent = tmp;
1536		    last = NULL;
1537		    cur = xmlXPtrGetNthChild(cur, index1 - 1);
1538		    index1 = 0;
1539		    /*
1540		     * Now gather the remaining nodes from cur to end
1541		     */
1542		    continue; /* while */
1543		}
1544		tmp = xmlCopyNode(cur, 1);
1545		list = tmp;
1546		parent = NULL;
1547		last = tmp;
1548	    }
1549	} else {
1550	    tmp = NULL;
1551	    switch (cur->type) {
1552		case XML_DTD_NODE:
1553		case XML_ELEMENT_DECL:
1554		case XML_ATTRIBUTE_DECL:
1555		case XML_ENTITY_NODE:
1556		    /* Do not copy DTD informations */
1557		    break;
1558		case XML_ENTITY_DECL:
1559		    TODO /* handle crossing entities -> stack needed */
1560		    break;
1561		case XML_XINCLUDE_START:
1562		case XML_XINCLUDE_END:
1563		    /* don't consider it part of the tree content */
1564		    break;
1565		case XML_ATTRIBUTE_NODE:
1566		    /* Humm, should not happen ! */
1567		    STRANGE
1568		    break;
1569		default:
1570		    tmp = xmlCopyNode(cur, 1);
1571		    break;
1572	    }
1573	    if (tmp != NULL) {
1574		if ((list == NULL) || ((last == NULL) && (parent == NULL)))  {
1575		    STRANGE
1576		    return(NULL);
1577		}
1578		if (last != NULL)
1579		    xmlAddNextSibling(last, tmp);
1580		else {
1581		    xmlAddChild(parent, tmp);
1582		    last = tmp;
1583		}
1584	    }
1585	}
1586	/*
1587	 * Skip to next node in document order
1588	 */
1589	if ((list == NULL) || ((last == NULL) && (parent == NULL)))  {
1590	    STRANGE
1591	    return(NULL);
1592	}
1593	cur = xmlXPtrAdvanceNode(cur, NULL);
1594    }
1595    return(list);
1596}
1597
1598/**
1599 * xmlXPtrBuildNodeList:
1600 * @obj:  the XPointer result from the evaluation.
1601 *
1602 * Build a node list tree copy of the XPointer result.
1603 * This will drop Attributes and Namespace declarations.
1604 *
1605 * Returns an xmlNodePtr list or NULL.
1606 *         the caller has to free the node tree.
1607 */
1608xmlNodePtr
1609xmlXPtrBuildNodeList(xmlXPathObjectPtr obj) {
1610    xmlNodePtr list = NULL, last = NULL;
1611    int i;
1612
1613    if (obj == NULL)
1614	return(NULL);
1615    switch (obj->type) {
1616        case XPATH_NODESET: {
1617	    xmlNodeSetPtr set = obj->nodesetval;
1618	    if (set == NULL)
1619		return(NULL);
1620	    for (i = 0;i < set->nodeNr;i++) {
1621		if (set->nodeTab[i] == NULL)
1622		    continue;
1623		switch (set->nodeTab[i]->type) {
1624		    case XML_TEXT_NODE:
1625		    case XML_CDATA_SECTION_NODE:
1626		    case XML_ELEMENT_NODE:
1627		    case XML_ENTITY_REF_NODE:
1628		    case XML_ENTITY_NODE:
1629		    case XML_PI_NODE:
1630		    case XML_COMMENT_NODE:
1631		    case XML_DOCUMENT_NODE:
1632		    case XML_HTML_DOCUMENT_NODE:
1633#ifdef LIBXML_DOCB_ENABLED
1634		    case XML_DOCB_DOCUMENT_NODE:
1635#endif
1636		    case XML_XINCLUDE_START:
1637		    case XML_XINCLUDE_END:
1638			break;
1639		    case XML_ATTRIBUTE_NODE:
1640		    case XML_NAMESPACE_DECL:
1641		    case XML_DOCUMENT_TYPE_NODE:
1642		    case XML_DOCUMENT_FRAG_NODE:
1643		    case XML_NOTATION_NODE:
1644		    case XML_DTD_NODE:
1645		    case XML_ELEMENT_DECL:
1646		    case XML_ATTRIBUTE_DECL:
1647		    case XML_ENTITY_DECL:
1648			continue; /* for */
1649		}
1650		if (last == NULL)
1651		    list = last = xmlCopyNode(set->nodeTab[i], 1);
1652		else {
1653		    xmlAddNextSibling(last, xmlCopyNode(set->nodeTab[i], 1));
1654		    if (last->next != NULL)
1655			last = last->next;
1656		}
1657	    }
1658	    break;
1659	}
1660	case XPATH_LOCATIONSET: {
1661	    xmlLocationSetPtr set = (xmlLocationSetPtr) obj->user;
1662	    if (set == NULL)
1663		return(NULL);
1664	    for (i = 0;i < set->locNr;i++) {
1665		if (last == NULL)
1666		    list = last = xmlXPtrBuildNodeList(set->locTab[i]);
1667		else
1668		    xmlAddNextSibling(last,
1669			    xmlXPtrBuildNodeList(set->locTab[i]));
1670		if (last != NULL) {
1671		    while (last->next != NULL)
1672			last = last->next;
1673		}
1674	    }
1675	    break;
1676	}
1677	case XPATH_RANGE:
1678	    return(xmlXPtrBuildRangeNodeList(obj));
1679	case XPATH_POINT:
1680	    return(xmlCopyNode(obj->user, 0));
1681	default:
1682	    break;
1683    }
1684    return(list);
1685}
1686
1687/************************************************************************
1688 *									*
1689 *			XPointer functions				*
1690 *									*
1691 ************************************************************************/
1692
1693/**
1694 * xmlXPtrNbLocChildren:
1695 * @node:  an xmlNodePtr
1696 *
1697 * Count the number of location children of @node or the length of the
1698 * string value in case of text/PI/Comments nodes
1699 *
1700 * Returns the number of location children
1701 */
1702static int
1703xmlXPtrNbLocChildren(xmlNodePtr node) {
1704    int ret = 0;
1705    if (node == NULL)
1706	return(-1);
1707    switch (node->type) {
1708        case XML_HTML_DOCUMENT_NODE:
1709        case XML_DOCUMENT_NODE:
1710        case XML_ELEMENT_NODE:
1711	    node = node->children;
1712	    while (node != NULL) {
1713		if (node->type == XML_ELEMENT_NODE)
1714		    ret++;
1715		node = node->next;
1716	    }
1717	    break;
1718        case XML_ATTRIBUTE_NODE:
1719	    return(-1);
1720
1721        case XML_PI_NODE:
1722        case XML_COMMENT_NODE:
1723        case XML_TEXT_NODE:
1724        case XML_CDATA_SECTION_NODE:
1725        case XML_ENTITY_REF_NODE:
1726	    ret = xmlStrlen(node->content);
1727	    break;
1728	default:
1729	    return(-1);
1730    }
1731    return(ret);
1732}
1733
1734/**
1735 * xmlXPtrHereFunction:
1736 * @ctxt:  the XPointer Parser context
1737 * @nargs:  the number of args
1738 *
1739 * Function implementing here() operation
1740 * as described in 5.4.3
1741 */
1742static void
1743xmlXPtrHereFunction(xmlXPathParserContextPtr ctxt, int nargs) {
1744    CHECK_ARITY(0);
1745
1746    if (ctxt->context->here == NULL)
1747	XP_ERROR(XPTR_SYNTAX_ERROR);
1748
1749    valuePush(ctxt, xmlXPtrNewLocationSetNodes(ctxt->context->here, NULL));
1750}
1751
1752/**
1753 * xmlXPtrOriginFunction:
1754 * @ctxt:  the XPointer Parser context
1755 * @nargs:  the number of args
1756 *
1757 * Function implementing origin() operation
1758 * as described in 5.4.3
1759 */
1760static void
1761xmlXPtrOriginFunction(xmlXPathParserContextPtr ctxt, int nargs) {
1762    CHECK_ARITY(0);
1763
1764    if (ctxt->context->origin == NULL)
1765	XP_ERROR(XPTR_SYNTAX_ERROR);
1766
1767    valuePush(ctxt, xmlXPtrNewLocationSetNodes(ctxt->context->origin, NULL));
1768}
1769
1770/**
1771 * xmlXPtrStartPointFunction:
1772 * @ctxt:  the XPointer Parser context
1773 * @nargs:  the number of args
1774 *
1775 * Function implementing start-point() operation
1776 * as described in 5.4.3
1777 * ----------------
1778 * location-set start-point(location-set)
1779 *
1780 * For each location x in the argument location-set, start-point adds a
1781 * location of type point to the result location-set. That point represents
1782 * the start point of location x and is determined by the following rules:
1783 *
1784 * - If x is of type point, the start point is x.
1785 * - If x is of type range, the start point is the start point of x.
1786 * - If x is of type root, element, text, comment, or processing instruction,
1787 * - the container node of the start point is x and the index is 0.
1788 * - If x is of type attribute or namespace, the function must signal a
1789 *   syntax error.
1790 * ----------------
1791 *
1792 */
1793static void
1794xmlXPtrStartPointFunction(xmlXPathParserContextPtr ctxt, int nargs) {
1795    xmlXPathObjectPtr tmp, obj, point;
1796    xmlLocationSetPtr newset = NULL;
1797    xmlLocationSetPtr oldset = NULL;
1798
1799    CHECK_ARITY(1);
1800    if ((ctxt->value == NULL) ||
1801	((ctxt->value->type != XPATH_LOCATIONSET) &&
1802	 (ctxt->value->type != XPATH_NODESET)))
1803        XP_ERROR(XPATH_INVALID_TYPE)
1804
1805    obj = valuePop(ctxt);
1806    if (obj->type == XPATH_NODESET) {
1807	/*
1808	 * First convert to a location set
1809	 */
1810	tmp = xmlXPtrNewLocationSetNodeSet(obj->nodesetval);
1811	xmlXPathFreeObject(obj);
1812	if (tmp == NULL)
1813            XP_ERROR(XPATH_MEMORY_ERROR)
1814	obj = tmp;
1815    }
1816
1817    newset = xmlXPtrLocationSetCreate(NULL);
1818    if (newset == NULL) {
1819	xmlXPathFreeObject(obj);
1820        XP_ERROR(XPATH_MEMORY_ERROR);
1821    }
1822    oldset = (xmlLocationSetPtr) obj->user;
1823    if (oldset != NULL) {
1824	int i;
1825
1826	for (i = 0; i < oldset->locNr; i++) {
1827	    tmp = oldset->locTab[i];
1828	    if (tmp == NULL)
1829		continue;
1830	    point = NULL;
1831	    switch (tmp->type) {
1832		case XPATH_POINT:
1833		    point = xmlXPtrNewPoint(tmp->user, tmp->index);
1834		    break;
1835		case XPATH_RANGE: {
1836		    xmlNodePtr node = tmp->user;
1837		    if (node != NULL) {
1838			if (node->type == XML_ATTRIBUTE_NODE) {
1839			    /* TODO: Namespace Nodes ??? */
1840			    xmlXPathFreeObject(obj);
1841			    xmlXPtrFreeLocationSet(newset);
1842			    XP_ERROR(XPTR_SYNTAX_ERROR);
1843			}
1844			point = xmlXPtrNewPoint(node, tmp->index);
1845		    }
1846		    break;
1847	        }
1848		default:
1849		    /*** Should we raise an error ?
1850		    xmlXPathFreeObject(obj);
1851		    xmlXPathFreeObject(newset);
1852		    XP_ERROR(XPATH_INVALID_TYPE)
1853		    ***/
1854		    break;
1855	    }
1856            if (point != NULL)
1857		xmlXPtrLocationSetAdd(newset, point);
1858	}
1859    }
1860    xmlXPathFreeObject(obj);
1861    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
1862}
1863
1864/**
1865 * xmlXPtrEndPointFunction:
1866 * @ctxt:  the XPointer Parser context
1867 * @nargs:  the number of args
1868 *
1869 * Function implementing end-point() operation
1870 * as described in 5.4.3
1871 * ----------------------------
1872 * location-set end-point(location-set)
1873 *
1874 * For each location x in the argument location-set, end-point adds a
1875 * location of type point to the result location-set. That point represents
1876 * the end point of location x and is determined by the following rules:
1877 *
1878 * - If x is of type point, the resulting point is x.
1879 * - If x is of type range, the resulting point is the end point of x.
1880 * - If x is of type root or element, the container node of the resulting
1881 *   point is x and the index is the number of location children of x.
1882 * - If x is of type text, comment, or processing instruction, the container
1883 *   node of the resulting point is x and the index is the length of the
1884 *   string-value of x.
1885 * - If x is of type attribute or namespace, the function must signal a
1886 *   syntax error.
1887 * ----------------------------
1888 */
1889static void
1890xmlXPtrEndPointFunction(xmlXPathParserContextPtr ctxt, int nargs) {
1891    xmlXPathObjectPtr tmp, obj, point;
1892    xmlLocationSetPtr newset = NULL;
1893    xmlLocationSetPtr oldset = NULL;
1894
1895    CHECK_ARITY(1);
1896    if ((ctxt->value == NULL) ||
1897	((ctxt->value->type != XPATH_LOCATIONSET) &&
1898	 (ctxt->value->type != XPATH_NODESET)))
1899        XP_ERROR(XPATH_INVALID_TYPE)
1900
1901    obj = valuePop(ctxt);
1902    if (obj->type == XPATH_NODESET) {
1903	/*
1904	 * First convert to a location set
1905	 */
1906	tmp = xmlXPtrNewLocationSetNodeSet(obj->nodesetval);
1907	xmlXPathFreeObject(obj);
1908	if (tmp == NULL)
1909            XP_ERROR(XPATH_MEMORY_ERROR)
1910	obj = tmp;
1911    }
1912
1913    newset = xmlXPtrLocationSetCreate(NULL);
1914    if (newset == NULL) {
1915	xmlXPathFreeObject(obj);
1916        XP_ERROR(XPATH_MEMORY_ERROR);
1917    }
1918    oldset = (xmlLocationSetPtr) obj->user;
1919    if (oldset != NULL) {
1920	int i;
1921
1922	for (i = 0; i < oldset->locNr; i++) {
1923	    tmp = oldset->locTab[i];
1924	    if (tmp == NULL)
1925		continue;
1926	    point = NULL;
1927	    switch (tmp->type) {
1928		case XPATH_POINT:
1929		    point = xmlXPtrNewPoint(tmp->user, tmp->index);
1930		    break;
1931		case XPATH_RANGE: {
1932		    xmlNodePtr node = tmp->user2;
1933		    if (node != NULL) {
1934			if (node->type == XML_ATTRIBUTE_NODE) {
1935			    /* TODO: Namespace Nodes ??? */
1936			    xmlXPathFreeObject(obj);
1937			    xmlXPtrFreeLocationSet(newset);
1938			    XP_ERROR(XPTR_SYNTAX_ERROR);
1939			}
1940			point = xmlXPtrNewPoint(node, tmp->index2);
1941		    } else if (tmp->user == NULL) {
1942			point = xmlXPtrNewPoint(node,
1943				       xmlXPtrNbLocChildren(node));
1944		    }
1945		    break;
1946	        }
1947		default:
1948		    /*** Should we raise an error ?
1949		    xmlXPathFreeObject(obj);
1950		    xmlXPathFreeObject(newset);
1951		    XP_ERROR(XPATH_INVALID_TYPE)
1952		    ***/
1953		    break;
1954	    }
1955            if (point != NULL)
1956		xmlXPtrLocationSetAdd(newset, point);
1957	}
1958    }
1959    xmlXPathFreeObject(obj);
1960    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
1961}
1962
1963
1964/**
1965 * xmlXPtrCoveringRange:
1966 * @ctxt:  the XPointer Parser context
1967 * @loc:  the location for which the covering range must be computed
1968 *
1969 * A covering range is a range that wholly encompasses a location
1970 * Section 5.3.3. Covering Ranges for All Location Types
1971 *        http://www.w3.org/TR/xptr#N2267
1972 *
1973 * Returns a new location or NULL in case of error
1974 */
1975static xmlXPathObjectPtr
1976xmlXPtrCoveringRange(xmlXPathParserContextPtr ctxt, xmlXPathObjectPtr loc) {
1977    if (loc == NULL)
1978	return(NULL);
1979    if ((ctxt == NULL) || (ctxt->context == NULL) ||
1980	(ctxt->context->doc == NULL))
1981	return(NULL);
1982    switch (loc->type) {
1983        case XPATH_POINT:
1984	    return(xmlXPtrNewRange(loc->user, loc->index,
1985			           loc->user, loc->index));
1986        case XPATH_RANGE:
1987	    if (loc->user2 != NULL) {
1988		return(xmlXPtrNewRange(loc->user, loc->index,
1989			              loc->user2, loc->index2));
1990	    } else {
1991		xmlNodePtr node = (xmlNodePtr) loc->user;
1992		if (node == (xmlNodePtr) ctxt->context->doc) {
1993		    return(xmlXPtrNewRange(node, 0, node,
1994					   xmlXPtrGetArity(node)));
1995		} else {
1996		    switch (node->type) {
1997			case XML_ATTRIBUTE_NODE:
1998			/* !!! our model is slightly different than XPath */
1999			    return(xmlXPtrNewRange(node, 0, node,
2000					           xmlXPtrGetArity(node)));
2001			case XML_ELEMENT_NODE:
2002			case XML_TEXT_NODE:
2003			case XML_CDATA_SECTION_NODE:
2004			case XML_ENTITY_REF_NODE:
2005			case XML_PI_NODE:
2006			case XML_COMMENT_NODE:
2007			case XML_DOCUMENT_NODE:
2008			case XML_NOTATION_NODE:
2009			case XML_HTML_DOCUMENT_NODE: {
2010			    int indx = xmlXPtrGetIndex(node);
2011
2012			    node = node->parent;
2013			    return(xmlXPtrNewRange(node, indx - 1,
2014					           node, indx + 1));
2015			}
2016			default:
2017			    return(NULL);
2018		    }
2019		}
2020	    }
2021	default:
2022	    TODO /* missed one case ??? */
2023    }
2024    return(NULL);
2025}
2026
2027/**
2028 * xmlXPtrRangeFunction:
2029 * @ctxt:  the XPointer Parser context
2030 * @nargs:  the number of args
2031 *
2032 * Function implementing the range() function 5.4.3
2033 *  location-set range(location-set )
2034 *
2035 *  The range function returns ranges covering the locations in
2036 *  the argument location-set. For each location x in the argument
2037 *  location-set, a range location representing the covering range of
2038 *  x is added to the result location-set.
2039 */
2040static void
2041xmlXPtrRangeFunction(xmlXPathParserContextPtr ctxt, int nargs) {
2042    int i;
2043    xmlXPathObjectPtr set;
2044    xmlLocationSetPtr oldset;
2045    xmlLocationSetPtr newset;
2046
2047    CHECK_ARITY(1);
2048    if ((ctxt->value == NULL) ||
2049	((ctxt->value->type != XPATH_LOCATIONSET) &&
2050	 (ctxt->value->type != XPATH_NODESET)))
2051        XP_ERROR(XPATH_INVALID_TYPE)
2052
2053    set = valuePop(ctxt);
2054    if (set->type == XPATH_NODESET) {
2055	xmlXPathObjectPtr tmp;
2056
2057	/*
2058	 * First convert to a location set
2059	 */
2060	tmp = xmlXPtrNewLocationSetNodeSet(set->nodesetval);
2061	xmlXPathFreeObject(set);
2062	if (tmp == NULL)
2063            XP_ERROR(XPATH_MEMORY_ERROR)
2064	set = tmp;
2065    }
2066    oldset = (xmlLocationSetPtr) set->user;
2067
2068    /*
2069     * The loop is to compute the covering range for each item and add it
2070     */
2071    newset = xmlXPtrLocationSetCreate(NULL);
2072    if (newset == NULL) {
2073	xmlXPathFreeObject(set);
2074        XP_ERROR(XPATH_MEMORY_ERROR);
2075    }
2076    for (i = 0;i < oldset->locNr;i++) {
2077	xmlXPtrLocationSetAdd(newset,
2078		xmlXPtrCoveringRange(ctxt, oldset->locTab[i]));
2079    }
2080
2081    /*
2082     * Save the new value and cleanup
2083     */
2084    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
2085    xmlXPathFreeObject(set);
2086}
2087
2088/**
2089 * xmlXPtrInsideRange:
2090 * @ctxt:  the XPointer Parser context
2091 * @loc:  the location for which the inside range must be computed
2092 *
2093 * A inside range is a range described in the range-inside() description
2094 *
2095 * Returns a new location or NULL in case of error
2096 */
2097static xmlXPathObjectPtr
2098xmlXPtrInsideRange(xmlXPathParserContextPtr ctxt, xmlXPathObjectPtr loc) {
2099    if (loc == NULL)
2100	return(NULL);
2101    if ((ctxt == NULL) || (ctxt->context == NULL) ||
2102	(ctxt->context->doc == NULL))
2103	return(NULL);
2104    switch (loc->type) {
2105        case XPATH_POINT: {
2106	    xmlNodePtr node = (xmlNodePtr) loc->user;
2107	    switch (node->type) {
2108		case XML_PI_NODE:
2109		case XML_COMMENT_NODE:
2110		case XML_TEXT_NODE:
2111		case XML_CDATA_SECTION_NODE: {
2112		    if (node->content == NULL) {
2113			return(xmlXPtrNewRange(node, 0, node, 0));
2114		    } else {
2115			return(xmlXPtrNewRange(node, 0, node,
2116					       xmlStrlen(node->content)));
2117		    }
2118		}
2119		case XML_ATTRIBUTE_NODE:
2120		case XML_ELEMENT_NODE:
2121		case XML_ENTITY_REF_NODE:
2122		case XML_DOCUMENT_NODE:
2123		case XML_NOTATION_NODE:
2124		case XML_HTML_DOCUMENT_NODE: {
2125		    return(xmlXPtrNewRange(node, 0, node,
2126					   xmlXPtrGetArity(node)));
2127		}
2128		default:
2129		    break;
2130	    }
2131	    return(NULL);
2132	}
2133        case XPATH_RANGE: {
2134	    xmlNodePtr node = (xmlNodePtr) loc->user;
2135	    if (loc->user2 != NULL) {
2136		return(xmlXPtrNewRange(node, loc->index,
2137			               loc->user2, loc->index2));
2138	    } else {
2139		switch (node->type) {
2140		    case XML_PI_NODE:
2141		    case XML_COMMENT_NODE:
2142		    case XML_TEXT_NODE:
2143		    case XML_CDATA_SECTION_NODE: {
2144			if (node->content == NULL) {
2145			    return(xmlXPtrNewRange(node, 0, node, 0));
2146			} else {
2147			    return(xmlXPtrNewRange(node, 0, node,
2148						   xmlStrlen(node->content)));
2149			}
2150		    }
2151		    case XML_ATTRIBUTE_NODE:
2152		    case XML_ELEMENT_NODE:
2153		    case XML_ENTITY_REF_NODE:
2154		    case XML_DOCUMENT_NODE:
2155		    case XML_NOTATION_NODE:
2156		    case XML_HTML_DOCUMENT_NODE: {
2157			return(xmlXPtrNewRange(node, 0, node,
2158					       xmlXPtrGetArity(node)));
2159		    }
2160		    default:
2161			break;
2162		}
2163		return(NULL);
2164	    }
2165        }
2166	default:
2167	    TODO /* missed one case ??? */
2168    }
2169    return(NULL);
2170}
2171
2172/**
2173 * xmlXPtrRangeInsideFunction:
2174 * @ctxt:  the XPointer Parser context
2175 * @nargs:  the number of args
2176 *
2177 * Function implementing the range-inside() function 5.4.3
2178 *  location-set range-inside(location-set )
2179 *
2180 *  The range-inside function returns ranges covering the contents of
2181 *  the locations in the argument location-set. For each location x in
2182 *  the argument location-set, a range location is added to the result
2183 *  location-set. If x is a range location, then x is added to the
2184 *  result location-set. If x is not a range location, then x is used
2185 *  as the container location of the start and end points of the range
2186 *  location to be added; the index of the start point of the range is
2187 *  zero; if the end point is a character point then its index is the
2188 *  length of the string-value of x, and otherwise is the number of
2189 *  location children of x.
2190 *
2191 */
2192static void
2193xmlXPtrRangeInsideFunction(xmlXPathParserContextPtr ctxt, int nargs) {
2194    int i;
2195    xmlXPathObjectPtr set;
2196    xmlLocationSetPtr oldset;
2197    xmlLocationSetPtr newset;
2198
2199    CHECK_ARITY(1);
2200    if ((ctxt->value == NULL) ||
2201	((ctxt->value->type != XPATH_LOCATIONSET) &&
2202	 (ctxt->value->type != XPATH_NODESET)))
2203        XP_ERROR(XPATH_INVALID_TYPE)
2204
2205    set = valuePop(ctxt);
2206    if (set->type == XPATH_NODESET) {
2207	xmlXPathObjectPtr tmp;
2208
2209	/*
2210	 * First convert to a location set
2211	 */
2212	tmp = xmlXPtrNewLocationSetNodeSet(set->nodesetval);
2213	xmlXPathFreeObject(set);
2214	if (tmp == NULL)
2215	     XP_ERROR(XPATH_MEMORY_ERROR)
2216	set = tmp;
2217    }
2218    oldset = (xmlLocationSetPtr) set->user;
2219
2220    /*
2221     * The loop is to compute the covering range for each item and add it
2222     */
2223    newset = xmlXPtrLocationSetCreate(NULL);
2224    if (newset == NULL) {
2225	xmlXPathFreeObject(set);
2226        XP_ERROR(XPATH_MEMORY_ERROR);
2227    }
2228    for (i = 0;i < oldset->locNr;i++) {
2229	xmlXPtrLocationSetAdd(newset,
2230		xmlXPtrInsideRange(ctxt, oldset->locTab[i]));
2231    }
2232
2233    /*
2234     * Save the new value and cleanup
2235     */
2236    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
2237    xmlXPathFreeObject(set);
2238}
2239
2240/**
2241 * xmlXPtrRangeToFunction:
2242 * @ctxt:  the XPointer Parser context
2243 * @nargs:  the number of args
2244 *
2245 * Implement the range-to() XPointer function
2246 */
2247void
2248xmlXPtrRangeToFunction(xmlXPathParserContextPtr ctxt, int nargs) {
2249    xmlXPathObjectPtr range;
2250    const xmlChar *cur;
2251    xmlXPathObjectPtr res, obj;
2252    xmlXPathObjectPtr tmp;
2253    xmlLocationSetPtr newset = NULL;
2254    xmlNodeSetPtr oldset;
2255    int i;
2256
2257    if (ctxt == NULL) return;
2258    CHECK_ARITY(1);
2259    /*
2260     * Save the expression pointer since we will have to evaluate
2261     * it multiple times. Initialize the new set.
2262     */
2263    CHECK_TYPE(XPATH_NODESET);
2264    obj = valuePop(ctxt);
2265    oldset = obj->nodesetval;
2266    ctxt->context->node = NULL;
2267
2268    cur = ctxt->cur;
2269    newset = xmlXPtrLocationSetCreate(NULL);
2270
2271    for (i = 0; i < oldset->nodeNr; i++) {
2272	ctxt->cur = cur;
2273
2274	/*
2275	 * Run the evaluation with a node list made of a single item
2276	 * in the nodeset.
2277	 */
2278	ctxt->context->node = oldset->nodeTab[i];
2279	tmp = xmlXPathNewNodeSet(ctxt->context->node);
2280	valuePush(ctxt, tmp);
2281
2282	xmlXPathEvalExpr(ctxt);
2283	CHECK_ERROR;
2284
2285	/*
2286	 * The result of the evaluation need to be tested to
2287	 * decided whether the filter succeeded or not
2288	 */
2289	res = valuePop(ctxt);
2290	range = xmlXPtrNewRangeNodeObject(oldset->nodeTab[i], res);
2291	if (range != NULL) {
2292	    xmlXPtrLocationSetAdd(newset, range);
2293	}
2294
2295	/*
2296	 * Cleanup
2297	 */
2298	if (res != NULL)
2299	    xmlXPathFreeObject(res);
2300	if (ctxt->value == tmp) {
2301	    res = valuePop(ctxt);
2302	    xmlXPathFreeObject(res);
2303	}
2304
2305	ctxt->context->node = NULL;
2306    }
2307
2308    /*
2309     * The result is used as the new evaluation set.
2310     */
2311    xmlXPathFreeObject(obj);
2312    ctxt->context->node = NULL;
2313    ctxt->context->contextSize = -1;
2314    ctxt->context->proximityPosition = -1;
2315    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
2316}
2317
2318/**
2319 * xmlXPtrAdvanceNode:
2320 * @cur:  the node
2321 * @level: incremented/decremented to show level in tree
2322 *
2323 * Advance to the next element or text node in document order
2324 * TODO: add a stack for entering/exiting entities
2325 *
2326 * Returns -1 in case of failure, 0 otherwise
2327 */
2328xmlNodePtr
2329xmlXPtrAdvanceNode(xmlNodePtr cur, int *level) {
2330next:
2331    if ((cur == NULL) || (cur->type == XML_NAMESPACE_DECL))
2332	return(NULL);
2333    if (cur->children != NULL) {
2334        cur = cur->children ;
2335	if (level != NULL)
2336	    (*level)++;
2337	goto found;
2338    }
2339skip:		/* This label should only be needed if something is wrong! */
2340    if (cur->next != NULL) {
2341	cur = cur->next;
2342	goto found;
2343    }
2344    do {
2345        cur = cur->parent;
2346	if (level != NULL)
2347	    (*level)--;
2348        if (cur == NULL) return(NULL);
2349        if (cur->next != NULL) {
2350	    cur = cur->next;
2351	    goto found;
2352	}
2353    } while (cur != NULL);
2354
2355found:
2356    if ((cur->type != XML_ELEMENT_NODE) &&
2357	(cur->type != XML_TEXT_NODE) &&
2358	(cur->type != XML_DOCUMENT_NODE) &&
2359	(cur->type != XML_HTML_DOCUMENT_NODE) &&
2360	(cur->type != XML_CDATA_SECTION_NODE)) {
2361	    if (cur->type == XML_ENTITY_REF_NODE) {	/* Shouldn't happen */
2362		TODO
2363		goto skip;
2364	    }
2365	    goto next;
2366	}
2367    return(cur);
2368}
2369
2370/**
2371 * xmlXPtrAdvanceChar:
2372 * @node:  the node
2373 * @indx:  the indx
2374 * @bytes:  the number of bytes
2375 *
2376 * Advance a point of the associated number of bytes (not UTF8 chars)
2377 *
2378 * Returns -1 in case of failure, 0 otherwise
2379 */
2380static int
2381xmlXPtrAdvanceChar(xmlNodePtr *node, int *indx, int bytes) {
2382    xmlNodePtr cur;
2383    int pos;
2384    int len;
2385
2386    if ((node == NULL) || (indx == NULL))
2387	return(-1);
2388    cur = *node;
2389    if ((cur == NULL) || (cur->type == XML_NAMESPACE_DECL))
2390	return(-1);
2391    pos = *indx;
2392
2393    while (bytes >= 0) {
2394	/*
2395	 * First position to the beginning of the first text node
2396	 * corresponding to this point
2397	 */
2398	while ((cur != NULL) &&
2399	       ((cur->type == XML_ELEMENT_NODE) ||
2400	        (cur->type == XML_DOCUMENT_NODE) ||
2401	        (cur->type == XML_HTML_DOCUMENT_NODE))) {
2402	    if (pos > 0) {
2403		cur = xmlXPtrGetNthChild(cur, pos);
2404		pos = 0;
2405	    } else {
2406		cur = xmlXPtrAdvanceNode(cur, NULL);
2407		pos = 0;
2408	    }
2409	}
2410
2411	if (cur == NULL) {
2412	    *node = NULL;
2413	    *indx = 0;
2414	    return(-1);
2415	}
2416
2417	/*
2418	 * if there is no move needed return the current value.
2419	 */
2420	if (pos == 0) pos = 1;
2421	if (bytes == 0) {
2422	    *node = cur;
2423	    *indx = pos;
2424	    return(0);
2425	}
2426	/*
2427	 * We should have a text (or cdata) node ...
2428	 */
2429	len = 0;
2430	if ((cur->type != XML_ELEMENT_NODE) &&
2431            (cur->content != NULL)) {
2432	    len = xmlStrlen(cur->content);
2433	}
2434	if (pos > len) {
2435	    /* Strange, the indx in the text node is greater than it's len */
2436	    STRANGE
2437	    pos = len;
2438	}
2439	if (pos + bytes >= len) {
2440	    bytes -= (len - pos);
2441	    cur = xmlXPtrAdvanceNode(cur, NULL);
2442	    pos = 0;
2443	} else if (pos + bytes < len) {
2444	    pos += bytes;
2445	    *node = cur;
2446	    *indx = pos;
2447	    return(0);
2448	}
2449    }
2450    return(-1);
2451}
2452
2453/**
2454 * xmlXPtrMatchString:
2455 * @string:  the string to search
2456 * @start:  the start textnode
2457 * @startindex:  the start index
2458 * @end:  the end textnode IN/OUT
2459 * @endindex:  the end index IN/OUT
2460 *
2461 * Check whether the document contains @string at the position
2462 * (@start, @startindex) and limited by the (@end, @endindex) point
2463 *
2464 * Returns -1 in case of failure, 0 if not found, 1 if found in which case
2465 *            (@start, @startindex) will indicate the position of the beginning
2466 *            of the range and (@end, @endindex) will indicate the end
2467 *            of the range
2468 */
2469static int
2470xmlXPtrMatchString(const xmlChar *string, xmlNodePtr start, int startindex,
2471	            xmlNodePtr *end, int *endindex) {
2472    xmlNodePtr cur;
2473    int pos; /* 0 based */
2474    int len; /* in bytes */
2475    int stringlen; /* in bytes */
2476    int match;
2477
2478    if (string == NULL)
2479	return(-1);
2480    if ((start == NULL) || (start->type == XML_NAMESPACE_DECL))
2481	return(-1);
2482    if ((end == NULL) || (*end == NULL) ||
2483        ((*end)->type == XML_NAMESPACE_DECL) || (endindex == NULL))
2484	return(-1);
2485    cur = start;
2486    pos = startindex - 1;
2487    stringlen = xmlStrlen(string);
2488
2489    while (stringlen > 0) {
2490	if ((cur == *end) && (pos + stringlen > *endindex))
2491	    return(0);
2492
2493	if ((cur->type != XML_ELEMENT_NODE) && (cur->content != NULL)) {
2494	    len = xmlStrlen(cur->content);
2495	    if (len >= pos + stringlen) {
2496		match = (!xmlStrncmp(&cur->content[pos], string, stringlen));
2497		if (match) {
2498#ifdef DEBUG_RANGES
2499		    xmlGenericError(xmlGenericErrorContext,
2500			    "found range %d bytes at index %d of ->",
2501			    stringlen, pos + 1);
2502		    xmlDebugDumpString(stdout, cur->content);
2503		    xmlGenericError(xmlGenericErrorContext, "\n");
2504#endif
2505		    *end = cur;
2506		    *endindex = pos + stringlen;
2507		    return(1);
2508		} else {
2509		    return(0);
2510		}
2511	    } else {
2512                int sub = len - pos;
2513		match = (!xmlStrncmp(&cur->content[pos], string, sub));
2514		if (match) {
2515#ifdef DEBUG_RANGES
2516		    xmlGenericError(xmlGenericErrorContext,
2517			    "found subrange %d bytes at index %d of ->",
2518			    sub, pos + 1);
2519		    xmlDebugDumpString(stdout, cur->content);
2520		    xmlGenericError(xmlGenericErrorContext, "\n");
2521#endif
2522                    string = &string[sub];
2523		    stringlen -= sub;
2524		} else {
2525		    return(0);
2526		}
2527	    }
2528	}
2529	cur = xmlXPtrAdvanceNode(cur, NULL);
2530	if (cur == NULL)
2531	    return(0);
2532	pos = 0;
2533    }
2534    return(1);
2535}
2536
2537/**
2538 * xmlXPtrSearchString:
2539 * @string:  the string to search
2540 * @start:  the start textnode IN/OUT
2541 * @startindex:  the start index IN/OUT
2542 * @end:  the end textnode
2543 * @endindex:  the end index
2544 *
2545 * Search the next occurrence of @string within the document content
2546 * until the (@end, @endindex) point is reached
2547 *
2548 * Returns -1 in case of failure, 0 if not found, 1 if found in which case
2549 *            (@start, @startindex) will indicate the position of the beginning
2550 *            of the range and (@end, @endindex) will indicate the end
2551 *            of the range
2552 */
2553static int
2554xmlXPtrSearchString(const xmlChar *string, xmlNodePtr *start, int *startindex,
2555	            xmlNodePtr *end, int *endindex) {
2556    xmlNodePtr cur;
2557    const xmlChar *str;
2558    int pos; /* 0 based */
2559    int len; /* in bytes */
2560    xmlChar first;
2561
2562    if (string == NULL)
2563	return(-1);
2564    if ((start == NULL) || (*start == NULL) ||
2565        ((*start)->type == XML_NAMESPACE_DECL) || (startindex == NULL))
2566	return(-1);
2567    if ((end == NULL) || (endindex == NULL))
2568	return(-1);
2569    cur = *start;
2570    pos = *startindex - 1;
2571    first = string[0];
2572
2573    while (cur != NULL) {
2574	if ((cur->type != XML_ELEMENT_NODE) && (cur->content != NULL)) {
2575	    len = xmlStrlen(cur->content);
2576	    while (pos <= len) {
2577		if (first != 0) {
2578		    str = xmlStrchr(&cur->content[pos], first);
2579		    if (str != NULL) {
2580			pos = (str - (xmlChar *)(cur->content));
2581#ifdef DEBUG_RANGES
2582			xmlGenericError(xmlGenericErrorContext,
2583				"found '%c' at index %d of ->",
2584				first, pos + 1);
2585			xmlDebugDumpString(stdout, cur->content);
2586			xmlGenericError(xmlGenericErrorContext, "\n");
2587#endif
2588			if (xmlXPtrMatchString(string, cur, pos + 1,
2589					       end, endindex)) {
2590			    *start = cur;
2591			    *startindex = pos + 1;
2592			    return(1);
2593			}
2594			pos++;
2595		    } else {
2596			pos = len + 1;
2597		    }
2598		} else {
2599		    /*
2600		     * An empty string is considered to match before each
2601		     * character of the string-value and after the final
2602		     * character.
2603		     */
2604#ifdef DEBUG_RANGES
2605		    xmlGenericError(xmlGenericErrorContext,
2606			    "found '' at index %d of ->",
2607			    pos + 1);
2608		    xmlDebugDumpString(stdout, cur->content);
2609		    xmlGenericError(xmlGenericErrorContext, "\n");
2610#endif
2611		    *start = cur;
2612		    *startindex = pos + 1;
2613		    *end = cur;
2614		    *endindex = pos + 1;
2615		    return(1);
2616		}
2617	    }
2618	}
2619	if ((cur == *end) && (pos >= *endindex))
2620	    return(0);
2621	cur = xmlXPtrAdvanceNode(cur, NULL);
2622	if (cur == NULL)
2623	    return(0);
2624	pos = 1;
2625    }
2626    return(0);
2627}
2628
2629/**
2630 * xmlXPtrGetLastChar:
2631 * @node:  the node
2632 * @index:  the index
2633 *
2634 * Computes the point coordinates of the last char of this point
2635 *
2636 * Returns -1 in case of failure, 0 otherwise
2637 */
2638static int
2639xmlXPtrGetLastChar(xmlNodePtr *node, int *indx) {
2640    xmlNodePtr cur;
2641    int pos, len = 0;
2642
2643    if ((node == NULL) || (*node == NULL) ||
2644        ((*node)->type == XML_NAMESPACE_DECL) || (indx == NULL))
2645	return(-1);
2646    cur = *node;
2647    pos = *indx;
2648
2649    if ((cur->type == XML_ELEMENT_NODE) ||
2650	(cur->type == XML_DOCUMENT_NODE) ||
2651	(cur->type == XML_HTML_DOCUMENT_NODE)) {
2652	if (pos > 0) {
2653	    cur = xmlXPtrGetNthChild(cur, pos);
2654	}
2655    }
2656    while (cur != NULL) {
2657	if (cur->last != NULL)
2658	    cur = cur->last;
2659	else if ((cur->type != XML_ELEMENT_NODE) &&
2660	         (cur->content != NULL)) {
2661	    len = xmlStrlen(cur->content);
2662	    break;
2663	} else {
2664	    return(-1);
2665	}
2666    }
2667    if (cur == NULL)
2668	return(-1);
2669    *node = cur;
2670    *indx = len;
2671    return(0);
2672}
2673
2674/**
2675 * xmlXPtrGetStartPoint:
2676 * @obj:  an range
2677 * @node:  the resulting node
2678 * @indx:  the resulting index
2679 *
2680 * read the object and return the start point coordinates.
2681 *
2682 * Returns -1 in case of failure, 0 otherwise
2683 */
2684static int
2685xmlXPtrGetStartPoint(xmlXPathObjectPtr obj, xmlNodePtr *node, int *indx) {
2686    if ((obj == NULL) || (node == NULL) || (indx == NULL))
2687	return(-1);
2688
2689    switch (obj->type) {
2690        case XPATH_POINT:
2691	    *node = obj->user;
2692	    if (obj->index <= 0)
2693		*indx = 0;
2694	    else
2695		*indx = obj->index;
2696	    return(0);
2697        case XPATH_RANGE:
2698	    *node = obj->user;
2699	    if (obj->index <= 0)
2700		*indx = 0;
2701	    else
2702		*indx = obj->index;
2703	    return(0);
2704	default:
2705	    break;
2706    }
2707    return(-1);
2708}
2709
2710/**
2711 * xmlXPtrGetEndPoint:
2712 * @obj:  an range
2713 * @node:  the resulting node
2714 * @indx:  the resulting indx
2715 *
2716 * read the object and return the end point coordinates.
2717 *
2718 * Returns -1 in case of failure, 0 otherwise
2719 */
2720static int
2721xmlXPtrGetEndPoint(xmlXPathObjectPtr obj, xmlNodePtr *node, int *indx) {
2722    if ((obj == NULL) || (node == NULL) || (indx == NULL))
2723	return(-1);
2724
2725    switch (obj->type) {
2726        case XPATH_POINT:
2727	    *node = obj->user;
2728	    if (obj->index <= 0)
2729		*indx = 0;
2730	    else
2731		*indx = obj->index;
2732	    return(0);
2733        case XPATH_RANGE:
2734	    *node = obj->user;
2735	    if (obj->index <= 0)
2736		*indx = 0;
2737	    else
2738		*indx = obj->index;
2739	    return(0);
2740	default:
2741	    break;
2742    }
2743    return(-1);
2744}
2745
2746/**
2747 * xmlXPtrStringRangeFunction:
2748 * @ctxt:  the XPointer Parser context
2749 * @nargs:  the number of args
2750 *
2751 * Function implementing the string-range() function
2752 * range as described in 5.4.2
2753 *
2754 * ------------------------------
2755 * [Definition: For each location in the location-set argument,
2756 * string-range returns a set of string ranges, a set of substrings in a
2757 * string. Specifically, the string-value of the location is searched for
2758 * substrings that match the string argument, and the resulting location-set
2759 * will contain a range location for each non-overlapping match.]
2760 * An empty string is considered to match before each character of the
2761 * string-value and after the final character. Whitespace in a string
2762 * is matched literally, with no normalization except that provided by
2763 * XML for line ends. The third argument gives the position of the first
2764 * character to be in the resulting range, relative to the start of the
2765 * match. The default value is 1, which makes the range start immediately
2766 * before the first character of the matched string. The fourth argument
2767 * gives the number of characters in the range; the default is that the
2768 * range extends to the end of the matched string.
2769 *
2770 * Element boundaries, as well as entire embedded nodes such as processing
2771 * instructions and comments, are ignored as defined in [XPath].
2772 *
2773 * If the string in the second argument is not found in the string-value
2774 * of the location, or if a value in the third or fourth argument indicates
2775 * a string that is beyond the beginning or end of the document, the
2776 * expression fails.
2777 *
2778 * The points of the range-locations in the returned location-set will
2779 * all be character points.
2780 * ------------------------------
2781 */
2782static void
2783xmlXPtrStringRangeFunction(xmlXPathParserContextPtr ctxt, int nargs) {
2784    int i, startindex, endindex = 0, fendindex;
2785    xmlNodePtr start, end = 0, fend;
2786    xmlXPathObjectPtr set;
2787    xmlLocationSetPtr oldset;
2788    xmlLocationSetPtr newset;
2789    xmlXPathObjectPtr string;
2790    xmlXPathObjectPtr position = NULL;
2791    xmlXPathObjectPtr number = NULL;
2792    int found, pos = 0, num = 0;
2793
2794    /*
2795     * Grab the arguments
2796     */
2797    if ((nargs < 2) || (nargs > 4))
2798	XP_ERROR(XPATH_INVALID_ARITY);
2799
2800    if (nargs >= 4) {
2801	CHECK_TYPE(XPATH_NUMBER);
2802	number = valuePop(ctxt);
2803	if (number != NULL)
2804	    num = (int) number->floatval;
2805    }
2806    if (nargs >= 3) {
2807	CHECK_TYPE(XPATH_NUMBER);
2808	position = valuePop(ctxt);
2809	if (position != NULL)
2810	    pos = (int) position->floatval;
2811    }
2812    CHECK_TYPE(XPATH_STRING);
2813    string = valuePop(ctxt);
2814    if ((ctxt->value == NULL) ||
2815	((ctxt->value->type != XPATH_LOCATIONSET) &&
2816	 (ctxt->value->type != XPATH_NODESET)))
2817        XP_ERROR(XPATH_INVALID_TYPE)
2818
2819    set = valuePop(ctxt);
2820    newset = xmlXPtrLocationSetCreate(NULL);
2821    if (newset == NULL) {
2822	xmlXPathFreeObject(set);
2823        XP_ERROR(XPATH_MEMORY_ERROR);
2824    }
2825    if (set->nodesetval == NULL) {
2826        goto error;
2827    }
2828    if (set->type == XPATH_NODESET) {
2829	xmlXPathObjectPtr tmp;
2830
2831	/*
2832	 * First convert to a location set
2833	 */
2834	tmp = xmlXPtrNewLocationSetNodeSet(set->nodesetval);
2835	xmlXPathFreeObject(set);
2836	if (tmp == NULL)
2837	     XP_ERROR(XPATH_MEMORY_ERROR)
2838	set = tmp;
2839    }
2840    oldset = (xmlLocationSetPtr) set->user;
2841
2842    /*
2843     * The loop is to search for each element in the location set
2844     * the list of location set corresponding to that search
2845     */
2846    for (i = 0;i < oldset->locNr;i++) {
2847#ifdef DEBUG_RANGES
2848	xmlXPathDebugDumpObject(stdout, oldset->locTab[i], 0);
2849#endif
2850
2851	xmlXPtrGetStartPoint(oldset->locTab[i], &start, &startindex);
2852	xmlXPtrGetEndPoint(oldset->locTab[i], &end, &endindex);
2853	xmlXPtrAdvanceChar(&start, &startindex, 0);
2854	xmlXPtrGetLastChar(&end, &endindex);
2855
2856#ifdef DEBUG_RANGES
2857	xmlGenericError(xmlGenericErrorContext,
2858		"from index %d of ->", startindex);
2859	xmlDebugDumpString(stdout, start->content);
2860	xmlGenericError(xmlGenericErrorContext, "\n");
2861	xmlGenericError(xmlGenericErrorContext,
2862		"to index %d of ->", endindex);
2863	xmlDebugDumpString(stdout, end->content);
2864	xmlGenericError(xmlGenericErrorContext, "\n");
2865#endif
2866	do {
2867            fend = end;
2868            fendindex = endindex;
2869	    found = xmlXPtrSearchString(string->stringval, &start, &startindex,
2870		                        &fend, &fendindex);
2871	    if (found == 1) {
2872		if (position == NULL) {
2873		    xmlXPtrLocationSetAdd(newset,
2874			 xmlXPtrNewRange(start, startindex, fend, fendindex));
2875		} else if (xmlXPtrAdvanceChar(&start, &startindex,
2876			                      pos - 1) == 0) {
2877		    if ((number != NULL) && (num > 0)) {
2878			int rindx;
2879			xmlNodePtr rend;
2880			rend = start;
2881			rindx = startindex - 1;
2882			if (xmlXPtrAdvanceChar(&rend, &rindx,
2883				               num) == 0) {
2884			    xmlXPtrLocationSetAdd(newset,
2885					xmlXPtrNewRange(start, startindex,
2886							rend, rindx));
2887			}
2888		    } else if ((number != NULL) && (num <= 0)) {
2889			xmlXPtrLocationSetAdd(newset,
2890				    xmlXPtrNewRange(start, startindex,
2891						    start, startindex));
2892		    } else {
2893			xmlXPtrLocationSetAdd(newset,
2894				    xmlXPtrNewRange(start, startindex,
2895						    fend, fendindex));
2896		    }
2897		}
2898		start = fend;
2899		startindex = fendindex;
2900		if (string->stringval[0] == 0)
2901		    startindex++;
2902	    }
2903	} while (found == 1);
2904    }
2905
2906    /*
2907     * Save the new value and cleanup
2908     */
2909error:
2910    valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
2911    xmlXPathFreeObject(set);
2912    xmlXPathFreeObject(string);
2913    if (position) xmlXPathFreeObject(position);
2914    if (number) xmlXPathFreeObject(number);
2915}
2916
2917/**
2918 * xmlXPtrEvalRangePredicate:
2919 * @ctxt:  the XPointer Parser context
2920 *
2921 *  [8]   Predicate ::=   '[' PredicateExpr ']'
2922 *  [9]   PredicateExpr ::=   Expr
2923 *
2924 * Evaluate a predicate as in xmlXPathEvalPredicate() but for
2925 * a Location Set instead of a node set
2926 */
2927void
2928xmlXPtrEvalRangePredicate(xmlXPathParserContextPtr ctxt) {
2929    const xmlChar *cur;
2930    xmlXPathObjectPtr res;
2931    xmlXPathObjectPtr obj, tmp;
2932    xmlLocationSetPtr newset = NULL;
2933    xmlLocationSetPtr oldset;
2934    int i;
2935
2936    if (ctxt == NULL) return;
2937
2938    SKIP_BLANKS;
2939    if (CUR != '[') {
2940	XP_ERROR(XPATH_INVALID_PREDICATE_ERROR);
2941    }
2942    NEXT;
2943    SKIP_BLANKS;
2944
2945    /*
2946     * Extract the old set, and then evaluate the result of the
2947     * expression for all the element in the set. use it to grow
2948     * up a new set.
2949     */
2950    CHECK_TYPE(XPATH_LOCATIONSET);
2951    obj = valuePop(ctxt);
2952    oldset = obj->user;
2953    ctxt->context->node = NULL;
2954
2955    if ((oldset == NULL) || (oldset->locNr == 0)) {
2956	ctxt->context->contextSize = 0;
2957	ctxt->context->proximityPosition = 0;
2958	xmlXPathEvalExpr(ctxt);
2959	res = valuePop(ctxt);
2960	if (res != NULL)
2961	    xmlXPathFreeObject(res);
2962	valuePush(ctxt, obj);
2963	CHECK_ERROR;
2964    } else {
2965	/*
2966	 * Save the expression pointer since we will have to evaluate
2967	 * it multiple times. Initialize the new set.
2968	 */
2969        cur = ctxt->cur;
2970	newset = xmlXPtrLocationSetCreate(NULL);
2971
2972        for (i = 0; i < oldset->locNr; i++) {
2973	    ctxt->cur = cur;
2974
2975	    /*
2976	     * Run the evaluation with a node list made of a single item
2977	     * in the nodeset.
2978	     */
2979	    ctxt->context->node = oldset->locTab[i]->user;
2980	    tmp = xmlXPathNewNodeSet(ctxt->context->node);
2981	    valuePush(ctxt, tmp);
2982	    ctxt->context->contextSize = oldset->locNr;
2983	    ctxt->context->proximityPosition = i + 1;
2984
2985	    xmlXPathEvalExpr(ctxt);
2986	    CHECK_ERROR;
2987
2988	    /*
2989	     * The result of the evaluation need to be tested to
2990	     * decided whether the filter succeeded or not
2991	     */
2992	    res = valuePop(ctxt);
2993	    if (xmlXPathEvaluatePredicateResult(ctxt, res)) {
2994	        xmlXPtrLocationSetAdd(newset,
2995			xmlXPathObjectCopy(oldset->locTab[i]));
2996	    }
2997
2998	    /*
2999	     * Cleanup
3000	     */
3001	    if (res != NULL)
3002		xmlXPathFreeObject(res);
3003	    if (ctxt->value == tmp) {
3004		res = valuePop(ctxt);
3005		xmlXPathFreeObject(res);
3006	    }
3007
3008	    ctxt->context->node = NULL;
3009	}
3010
3011	/*
3012	 * The result is used as the new evaluation set.
3013	 */
3014	xmlXPathFreeObject(obj);
3015	ctxt->context->node = NULL;
3016	ctxt->context->contextSize = -1;
3017	ctxt->context->proximityPosition = -1;
3018	valuePush(ctxt, xmlXPtrWrapLocationSet(newset));
3019    }
3020    if (CUR != ']') {
3021	XP_ERROR(XPATH_INVALID_PREDICATE_ERROR);
3022    }
3023
3024    NEXT;
3025    SKIP_BLANKS;
3026}
3027
3028#define bottom_xpointer
3029#include "elfgcchack.h"
3030#endif
3031
3032