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