1/*
2 * namespaces.c: Implementation of the XSLT namespaces handling
3 *
4 * Reference:
5 *   http://www.w3.org/TR/1999/REC-xslt-19991116
6 *
7 * See Copyright for the status of this software.
8 *
9 * daniel@veillard.com
10 */
11
12#define IN_LIBXSLT
13#include "libxslt.h"
14
15#include <string.h>
16
17#ifdef HAVE_SYS_TYPES_H
18#include <sys/types.h>
19#endif
20#ifdef HAVE_MATH_H
21#include <math.h>
22#endif
23#ifdef HAVE_FLOAT_H
24#include <float.h>
25#endif
26#ifdef HAVE_IEEEFP_H
27#include <ieeefp.h>
28#endif
29#ifdef HAVE_NAN_H
30#include <nan.h>
31#endif
32#ifdef HAVE_CTYPE_H
33#include <ctype.h>
34#endif
35#ifndef	XSLT_NEED_TRIO
36#include <stdio.h>
37#else
38#include <trio.h>
39#endif
40
41#include <libxml/xmlmemory.h>
42#include <libxml/tree.h>
43#include <libxml/hash.h>
44#include <libxml/xmlerror.h>
45#include <libxml/uri.h>
46#include "xslt.h"
47#include "xsltInternals.h"
48#include "xsltutils.h"
49#include "namespaces.h"
50#include "imports.h"
51
52/************************************************************************
53 *									*
54 *			Module interfaces				*
55 *									*
56 ************************************************************************/
57
58#ifdef XSLT_REFACTORED
59static xsltNsAliasPtr
60xsltNewNsAlias(xsltCompilerCtxtPtr cctxt)
61{
62    xsltNsAliasPtr ret;
63
64    if (cctxt == NULL)
65	return(NULL);
66
67    ret = (xsltNsAliasPtr) xmlMalloc(sizeof(xsltNsAlias));
68    if (ret == NULL) {
69	xsltTransformError(NULL, cctxt->style, NULL,
70	    "Internal error in xsltNewNsAlias(): Memory allocation failed.\n");
71	cctxt->style->errors++;
72	return(NULL);
73    }
74    memset(ret, 0, sizeof(xsltNsAlias));
75    /*
76    * TODO: Store the item at current stylesheet-level.
77    */
78    ret->next = cctxt->nsAliases;
79    cctxt->nsAliases = ret;
80
81    return(ret);
82}
83#endif /* XSLT_REFACTORED */
84/**
85 * xsltNamespaceAlias:
86 * @style:  the XSLT stylesheet
87 * @node:  the xsl:namespace-alias node
88 *
89 * Read the stylesheet-prefix and result-prefix attributes, register
90 * them as well as the corresponding namespace.
91 */
92void
93xsltNamespaceAlias(xsltStylesheetPtr style, xmlNodePtr node)
94{
95    xmlChar *resultPrefix = NULL;
96    xmlChar *stylePrefix = NULL;
97    xmlNsPtr literalNs = NULL;
98    xmlNsPtr targetNs = NULL;
99
100#ifdef XSLT_REFACTORED
101    xsltNsAliasPtr alias;
102
103    if ((style == NULL) || (node == NULL))
104	return;
105
106    /*
107    * SPEC XSLT 1.0:
108    *  "If a namespace URI is declared to be an alias for multiple
109    *  different namespace URIs, then the declaration with the highest
110    *  import precedence is used. It is an error if there is more than
111    *  one such declaration. An XSLT processor may signal the error;
112    *  if it does not signal the error, it must recover by choosing,
113    *  from amongst the declarations with the highest import precedence,
114    *  the one that occurs last in the stylesheet."
115    *
116    * SPEC TODO: Check for the errors mentioned above.
117    */
118    /*
119    * NOTE that the XSLT 2.0 also *does* use the NULL namespace if
120    *  "#default" is used and there's no default namespace is scope.
121    *  I.e., this is *not* an error.
122    *  Most XSLT 1.0 implementations work this way.
123    *  The XSLT 1.0 spec has nothing to say on the subject.
124    */
125    /*
126    * Attribute "stylesheet-prefix".
127    */
128    stylePrefix = xmlGetNsProp(node, (const xmlChar *)"stylesheet-prefix", NULL);
129    if (stylePrefix == NULL) {
130	xsltTransformError(NULL, style, node,
131	    "The attribute 'stylesheet-prefix' is missing.\n");
132	return;
133    }
134    if (xmlStrEqual(stylePrefix, (const xmlChar *)"#default"))
135	literalNs = xmlSearchNs(node->doc, node, NULL);
136    else {
137	literalNs = xmlSearchNs(node->doc, node, stylePrefix);
138	if (literalNs == NULL) {
139	    xsltTransformError(NULL, style, node,
140	        "Attribute 'stylesheet-prefix': There's no namespace "
141		"declaration in scope for the prefix '%s'.\n",
142		    stylePrefix);
143	    goto error;
144	}
145    }
146    /*
147    * Attribute "result-prefix".
148    */
149    resultPrefix = xmlGetNsProp(node, (const xmlChar *)"result-prefix", NULL);
150    if (resultPrefix == NULL) {
151	xsltTransformError(NULL, style, node,
152	    "The attribute 'result-prefix' is missing.\n");
153	goto error;
154    }
155    if (xmlStrEqual(resultPrefix, (const xmlChar *)"#default"))
156	targetNs = xmlSearchNs(node->doc, node, NULL);
157    else {
158	targetNs = xmlSearchNs(node->doc, node, resultPrefix);
159
160        if (targetNs == NULL) {
161	   xsltTransformError(NULL, style, node,
162	        "Attribute 'result-prefix': There's no namespace "
163		"declaration in scope for the prefix '%s'.\n",
164		    stylePrefix);
165	    goto error;
166	}
167    }
168    /*
169     *
170     * Same alias for multiple different target namespace URIs:
171     *  TODO: The one with the highest import precedence is used.
172     *  Example:
173     *  <xsl:namespace-alias stylesheet-prefix="foo"
174     *                       result-prefix="bar"/>
175     *
176     *  <xsl:namespace-alias stylesheet-prefix="foo"
177     *                       result-prefix="zar"/>
178     *
179     * Same target namespace URI for multiple different aliases:
180     *  All alias-definitions will be used.
181     *  Example:
182     *  <xsl:namespace-alias stylesheet-prefix="bar"
183     *                       result-prefix="foo"/>
184     *
185     *  <xsl:namespace-alias stylesheet-prefix="zar"
186     *                       result-prefix="foo"/>
187     * Cases using #default:
188     *  <xsl:namespace-alias stylesheet-prefix="#default"
189     *                       result-prefix="#default"/>
190     *  TODO: Has this an effect at all?
191     *
192     *  <xsl:namespace-alias stylesheet-prefix="foo"
193     *                       result-prefix="#default"/>
194     *  From namespace to no namespace.
195     *
196     *  <xsl:namespace-alias stylesheet-prefix="#default"
197     *                       result-prefix="foo"/>
198     *  From no namespace to namespace.
199     */
200
201
202     /*
203     * Store the ns-node in the alias-object.
204    */
205    alias = xsltNewNsAlias(XSLT_CCTXT(style));
206    if (alias == NULL)
207	return;
208    alias->literalNs = literalNs;
209    alias->targetNs = targetNs;
210    XSLT_CCTXT(style)->hasNsAliases = 1;
211
212
213#else /* XSLT_REFACTORED */
214    const xmlChar *literalNsName;
215    const xmlChar *targetNsName;
216
217
218    if ((style == NULL) || (node == NULL))
219	return;
220
221    stylePrefix = xmlGetNsProp(node, (const xmlChar *)"stylesheet-prefix", NULL);
222    if (stylePrefix == NULL) {
223	xsltTransformError(NULL, style, node,
224	    "namespace-alias: stylesheet-prefix attribute missing\n");
225	return;
226    }
227    resultPrefix = xmlGetNsProp(node, (const xmlChar *)"result-prefix", NULL);
228    if (resultPrefix == NULL) {
229	xsltTransformError(NULL, style, node,
230	    "namespace-alias: result-prefix attribute missing\n");
231	goto error;
232    }
233
234    if (xmlStrEqual(stylePrefix, (const xmlChar *)"#default")) {
235	literalNs = xmlSearchNs(node->doc, node, NULL);
236	if (literalNs == NULL) {
237	    literalNsName = NULL;
238	} else
239	    literalNsName = literalNs->href; /* Yes - set for nsAlias table */
240    } else {
241	literalNs = xmlSearchNs(node->doc, node, stylePrefix);
242
243	if ((literalNs == NULL) || (literalNs->href == NULL)) {
244	    xsltTransformError(NULL, style, node,
245	        "namespace-alias: prefix %s not bound to any namespace\n",
246					stylePrefix);
247	    goto error;
248	} else
249	    literalNsName = literalNs->href;
250    }
251
252    /*
253     * When "#default" is used for result, if a default namespace has not
254     * been explicitly declared the special value UNDEFINED_DEFAULT_NS is
255     * put into the nsAliases table
256     */
257    if (xmlStrEqual(resultPrefix, (const xmlChar *)"#default")) {
258	targetNs = xmlSearchNs(node->doc, node, NULL);
259	if (targetNs == NULL) {
260	    targetNsName = UNDEFINED_DEFAULT_NS;
261	} else
262	    targetNsName = targetNs->href;
263    } else {
264	targetNs = xmlSearchNs(node->doc, node, resultPrefix);
265
266        if ((targetNs == NULL) || (targetNs->href == NULL)) {
267	    xsltTransformError(NULL, style, node,
268	        "namespace-alias: prefix %s not bound to any namespace\n",
269					resultPrefix);
270	    goto error;
271	} else
272	    targetNsName = targetNs->href;
273    }
274    /*
275     * Special case: if #default is used for
276     *  the stylesheet-prefix (literal namespace) and there's no default
277     *  namespace in scope, we'll use style->defaultAlias for this.
278     */
279    if (literalNsName == NULL) {
280        if (targetNs != NULL) {
281	    /*
282	    * BUG TODO: Is it not sufficient to have only 1 field for
283	    *  this, since subsequently alias declarations will
284	    *  overwrite this.
285	    *  Example:
286	    *   <xsl:namespace-alias result-prefix="foo"
287	    *                        stylesheet-prefix="#default"/>
288	    *   <xsl:namespace-alias result-prefix="bar"
289	    *                        stylesheet-prefix="#default"/>
290	    *  The mapping for "foo" won't be visible anymore.
291	    */
292            style->defaultAlias = targetNs->href;
293	}
294    } else {
295        if (style->nsAliases == NULL)
296	    style->nsAliases = xmlHashCreate(10);
297        if (style->nsAliases == NULL) {
298	    xsltTransformError(NULL, style, node,
299	        "namespace-alias: cannot create hash table\n");
300	    goto error;
301        }
302	xmlHashAddEntry((xmlHashTablePtr) style->nsAliases,
303	    literalNsName, (void *) targetNsName);
304    }
305#endif /* else of XSLT_REFACTORED */
306
307error:
308    if (stylePrefix != NULL)
309	xmlFree(stylePrefix);
310    if (resultPrefix != NULL)
311	xmlFree(resultPrefix);
312}
313
314/**
315 * xsltGetSpecialNamespace:
316 * @ctxt:  the transformation context
317 * @invocNode: the invoking node; e.g. a literal result element/attr;
318 *             only used for error reports
319 * @nsName:  the namespace name (or NULL)
320 * @nsPrefix:  the suggested namespace prefix (or NULL)
321 * @target:  the result element on which to anchor a namespace
322 *
323 * Find a matching (prefix and ns-name) ns-declaration
324 * for the requested @nsName and @nsPrefix in the result tree.
325 * If none is found then a new ns-declaration will be
326 * added to @resultElem. If, in this case, the given prefix is
327 * already in use, then a ns-declaration with a modified ns-prefix
328 * be we created. Note that this function's priority is to
329 * preserve ns-prefixes; it will only change a prefix if there's
330 * a namespace clash.
331 * If both @nsName and @nsPrefix are NULL, then this will try to
332 * "undeclare" a default namespace by declaring an xmlns="".
333 *
334 * Returns a namespace declaration or NULL.
335 */
336xmlNsPtr
337xsltGetSpecialNamespace(xsltTransformContextPtr ctxt, xmlNodePtr invocNode,
338		const xmlChar *nsName, const xmlChar *nsPrefix,
339		xmlNodePtr target)
340{
341    xmlNsPtr ns;
342    int prefixOccupied = 0;
343
344    if ((ctxt == NULL) || (target == NULL) ||
345	(target->type != XML_ELEMENT_NODE))
346	return(NULL);
347
348    /*
349    * NOTE: Namespace exclusion and ns-aliasing is performed at
350    *  compilation-time in the refactored code; so this need not be done
351    *  here (it was in the old code).
352    * NOTE: @invocNode was named @cur in the old code and was documented to
353    *  be an input node; since it was only used to anchor an error report
354    *  somewhere, we can safely change this to @invocNode, which now
355    *  will be the XSLT instruction (also a literal result element/attribute),
356    *  which was responsible for this call.
357    */
358    /*
359    * OPTIMIZE TODO: This all could be optimized by keeping track of
360    *  the ns-decls currently in-scope via a specialized context.
361    */
362    if ((nsPrefix == NULL) && ((nsName == NULL) || (nsName[0] == 0))) {
363	/*
364	* NOTE: the "undeclaration" of the default namespace was
365	* part of the logic of the old xsltGetSpecialNamespace() code,
366	* so we'll keep that mechanism.
367	* Related to the old code: bug #302020:
368	*/
369	/*
370	* OPTIMIZE TODO: This all could be optimized by keeping track of
371	*  the ns-decls currently in-scope via a specialized context.
372	*/
373	/*
374	* Search on the result element itself.
375	*/
376	if (target->nsDef != NULL) {
377	    ns = target->nsDef;
378	    do {
379		if (ns->prefix == NULL) {
380		    if ((ns->href != NULL) && (ns->href[0] != 0)) {
381			/*
382			* Raise a namespace normalization error.
383			*/
384			xsltTransformError(ctxt, NULL, invocNode,
385			    "Namespace normalization error: Cannot undeclare "
386			    "the default namespace, since the default namespace "
387			    "'%s' is already declared on the result element "
388			    "'%s'.\n", ns->href, target->name);
389			return(NULL);
390		    } else {
391			/*
392			* The default namespace was undeclared on the
393			* result element.
394			*/
395			return(NULL);
396		    }
397		    break;
398		}
399		ns = ns->next;
400	    } while (ns != NULL);
401	}
402	if ((target->parent != NULL) &&
403	    (target->parent->type == XML_ELEMENT_NODE))
404	{
405	    /*
406	    * The parent element is in no namespace, so assume
407	    * that there is no default namespace in scope.
408	    */
409	    if (target->parent->ns == NULL)
410		return(NULL);
411
412	    ns = xmlSearchNs(target->doc, target->parent,
413		NULL);
414	    /*
415	    * Fine if there's no default ns is scope, or if the
416	    * default ns was undeclared.
417	    */
418	    if ((ns == NULL) || (ns->href == NULL) || (ns->href[0] == 0))
419		return(NULL);
420
421	    /*
422	    * Undeclare the default namespace.
423	    */
424	    xmlNewNs(target, BAD_CAST "", NULL);
425	    /* TODO: Check result */
426	    return(NULL);
427	}
428	return(NULL);
429    }
430    /*
431    * Handle the XML namespace.
432    * QUESTION: Is this faster than using xmlStrEqual() anyway?
433    */
434    if ((nsPrefix != NULL) &&
435	(nsPrefix[0] == 'x') && (nsPrefix[1] == 'm') &&
436	(nsPrefix[2] == 'l') && (nsPrefix[3] == 0))
437    {
438	return(xmlSearchNs(target->doc, target, nsPrefix));
439    }
440    /*
441    * First: search on the result element itself.
442    */
443    if (target->nsDef != NULL) {
444	ns = target->nsDef;
445	do {
446	    if ((ns->prefix == NULL) == (nsPrefix == NULL)) {
447		if (ns->prefix == nsPrefix) {
448		    if (xmlStrEqual(ns->href, nsName))
449			return(ns);
450		    prefixOccupied = 1;
451		    break;
452		} else if (xmlStrEqual(ns->prefix, nsPrefix)) {
453		    if (xmlStrEqual(ns->href, nsName))
454			return(ns);
455		    prefixOccupied = 1;
456		    break;
457		}
458	    }
459	    ns = ns->next;
460	} while (ns != NULL);
461    }
462    if (prefixOccupied) {
463	/*
464	* If the ns-prefix is occupied by an other ns-decl on the
465	* result element, then this means:
466	* 1) The desired prefix is shadowed
467	* 2) There's no way around changing the prefix
468	*
469	* Try a desperate search for an in-scope ns-decl
470	* with a matching ns-name before we use the last option,
471	* which is to recreate the ns-decl with a modified prefix.
472	*/
473	ns = xmlSearchNsByHref(target->doc, target, nsName);
474	if (ns != NULL)
475	    return(ns);
476
477	/*
478	* Fallback to changing the prefix.
479	*/
480    } else if ((target->parent != NULL) &&
481	(target->parent->type == XML_ELEMENT_NODE))
482    {
483	/*
484	* Try to find a matching ns-decl in the ancestor-axis.
485	*
486	* Check the common case: The parent element of the current
487	* result element is in the same namespace (with an equal ns-prefix).
488	*/
489	if ((target->parent->ns != NULL) &&
490	    ((target->parent->ns->prefix != NULL) == (nsPrefix != NULL)))
491	{
492	    ns = target->parent->ns;
493
494	    if (nsPrefix == NULL) {
495		if (xmlStrEqual(ns->href, nsName))
496		    return(ns);
497	    } else if (xmlStrEqual(ns->prefix, nsPrefix) &&
498		xmlStrEqual(ns->href, nsName))
499	    {
500		return(ns);
501	    }
502	}
503	/*
504	* Lookup the remaining in-scope namespaces.
505	*/
506	ns = xmlSearchNs(target->doc, target->parent, nsPrefix);
507	if (ns != NULL) {
508	    if (xmlStrEqual(ns->href, nsName))
509		return(ns);
510	    /*
511	    * Now check for a nasty case: We need to ensure that the new
512	    * ns-decl won't shadow a prefix in-use by an existing attribute.
513	    * <foo xmlns:a="urn:test:a">
514	    *   <bar a:a="val-a">
515	    *     <xsl:attribute xmlns:a="urn:test:b" name="a:b">
516	    *        val-b</xsl:attribute>
517	    *   </bar>
518	    * </foo>
519	    */
520	    if (target->properties) {
521		xmlAttrPtr attr = target->properties;
522		do {
523		    if ((attr->ns) &&
524			xmlStrEqual(attr->ns->prefix, nsPrefix))
525		    {
526			/*
527			* Bad, this prefix is already in use.
528			* Since we'll change the prefix anyway, try
529			* a search for a matching ns-decl based on the
530			* namespace name.
531			*/
532			ns = xmlSearchNsByHref(target->doc, target, nsName);
533			if (ns != NULL)
534			    return(ns);
535			goto declare_new_prefix;
536		    }
537		    attr = attr->next;
538		} while (attr != NULL);
539	    }
540	} else {
541	    /*
542	    * Either no matching ns-prefix was found or the namespace is
543	    * shadowed.
544	    * Create a new ns-decl on the current result element.
545	    *
546	    * Hmm, we could also try to reuse an in-scope
547	    * namespace with a matching ns-name but a different
548	    * ns-prefix.
549	    * What has higher priority?
550	    *  1) If keeping the prefix: create a new ns-decl.
551	    *  2) If reusal: first lookup ns-names; then fallback
552	    *     to creation of a new ns-decl.
553	    * REVISIT: this currently uses case 1) although
554	    *  the old way was use xmlSearchNsByHref() and to let change
555	    *  the prefix.
556	    */
557#if 0
558	    ns = xmlSearchNsByHref(target->doc, target, nsName);
559	    if (ns != NULL)
560		return(ns);
561#endif
562	}
563	/*
564	* Create the ns-decl on the current result element.
565	*/
566	ns = xmlNewNs(target, nsName, nsPrefix);
567	/* TODO: check errors */
568	return(ns);
569    } else {
570	/*
571	* This is either the root of the tree or something weird is going on.
572	*/
573	ns = xmlNewNs(target, nsName, nsPrefix);
574	/* TODO: Check result */
575	return(ns);
576    }
577
578declare_new_prefix:
579    /*
580    * Fallback: we need to generate a new prefix and declare the namespace
581    * on the result element.
582    */
583    {
584	xmlChar pref[30];
585	int counter = 1;
586
587	if (nsPrefix == NULL) {
588	    nsPrefix = "ns";
589	}
590
591	do {
592	    snprintf((char *) pref, 30, "%s_%d", nsPrefix, counter++);
593	    ns = xmlSearchNs(target->doc, target, BAD_CAST pref);
594	    if (counter > 1000) {
595		xsltTransformError(ctxt, NULL, invocNode,
596		    "Internal error in xsltAcquireResultInScopeNs(): "
597		    "Failed to compute a unique ns-prefix for the "
598		    "generated element");
599		return(NULL);
600	    }
601	} while (ns != NULL);
602	ns = xmlNewNs(target, nsName, BAD_CAST pref);
603	/* TODO: Check result */
604	return(ns);
605    }
606    return(NULL);
607}
608
609/**
610 * xsltGetNamespace:
611 * @ctxt:  a transformation context
612 * @cur:  the input node
613 * @ns:  the namespace
614 * @out:  the output node (or its parent)
615 *
616 * Find a matching (prefix and ns-name) ns-declaration
617 * for the requested @ns->prefix and @ns->href in the result tree.
618 * If none is found then a new ns-declaration will be
619 * added to @resultElem. If, in this case, the given prefix is
620 * already in use, then a ns-declaration with a modified ns-prefix
621 * be we created.
622 *
623 * Called by:
624 *  - xsltCopyPropList() (*not*  anymore)
625 *  - xsltShallowCopyElement()
626 *  - xsltCopyTreeInternal() (*not*  anymore)
627 *  - xsltApplySequenceConstructor() (*not* in the refactored code),
628 *  - xsltElement() (*not* anymore)
629 *
630 * Returns a namespace declaration or NULL in case of
631 *         namespace fixup failures or API or internal errors.
632 */
633xmlNsPtr
634xsltGetNamespace(xsltTransformContextPtr ctxt, xmlNodePtr cur, xmlNsPtr ns,
635	         xmlNodePtr out)
636{
637
638    if (ns == NULL)
639	return(NULL);
640
641#ifdef XSLT_REFACTORED
642    /*
643    * Namespace exclusion and ns-aliasing is performed at
644    * compilation-time in the refactored code.
645    * Additionally, aliasing is not intended for non Literal
646    * Result Elements.
647    */
648    return(xsltGetSpecialNamespace(ctxt, cur, ns->href, ns->prefix, out));
649#else
650    {
651	xsltStylesheetPtr style;
652	const xmlChar *URI = NULL; /* the replacement URI */
653
654	if ((ctxt == NULL) || (cur == NULL) || (out == NULL))
655	    return(NULL);
656
657	style = ctxt->style;
658	while (style != NULL) {
659	    if (style->nsAliases != NULL)
660		URI = (const xmlChar *)
661		xmlHashLookup(style->nsAliases, ns->href);
662	    if (URI != NULL)
663		break;
664
665	    style = xsltNextImport(style);
666	}
667
668
669	if (URI == UNDEFINED_DEFAULT_NS) {
670	    return(xsltGetSpecialNamespace(ctxt, cur, NULL, NULL, out));
671#if 0
672	    /*
673	    * TODO: Removed, since wrong. If there was no default
674	    * namespace in the stylesheet then this must resolve to
675	    * the NULL namespace.
676	    */
677	    xmlNsPtr dflt;
678	    dflt = xmlSearchNs(cur->doc, cur, NULL);
679	    if (dflt != NULL)
680		URI = dflt->href;
681	    else
682		return NULL;
683#endif
684	} else if (URI == NULL)
685	    URI = ns->href;
686
687	return(xsltGetSpecialNamespace(ctxt, cur, URI, ns->prefix, out));
688    }
689#endif
690}
691
692/**
693 * xsltGetPlainNamespace:
694 * @ctxt:  a transformation context
695 * @cur:  the input node
696 * @ns:  the namespace
697 * @out:  the result element
698 *
699 * Obsolete.
700 * *Not* called by any Libxslt/Libexslt function.
701 * Exaclty the same as xsltGetNamespace().
702 *
703 * Returns a namespace declaration or NULL in case of
704 *         namespace fixup failures or API or internal errors.
705 */
706xmlNsPtr
707xsltGetPlainNamespace(xsltTransformContextPtr ctxt, xmlNodePtr cur,
708                      xmlNsPtr ns, xmlNodePtr out)
709{
710    return(xsltGetNamespace(ctxt, cur, ns, out));
711}
712
713/**
714 * xsltCopyNamespaceList:
715 * @ctxt:  a transformation context
716 * @node:  the target node
717 * @cur:  the first namespace
718 *
719 * Do a copy of an namespace list. If @node is non-NULL the
720 * new namespaces are added automatically. This handles namespaces
721 * aliases.
722 * This function is intended only for *internal* use at
723 * transformation-time for copying ns-declarations of Literal
724 * Result Elements.
725 *
726 * Called by:
727 *   xsltCopyTreeInternal() (transform.c)
728 *   xsltShallowCopyElem() (transform.c)
729 *
730 * REVISIT: This function won't be used in the refactored code.
731 *
732 * Returns: a new xmlNsPtr, or NULL in case of error.
733 */
734xmlNsPtr
735xsltCopyNamespaceList(xsltTransformContextPtr ctxt, xmlNodePtr node,
736	              xmlNsPtr cur) {
737    xmlNsPtr ret = NULL, tmp;
738    xmlNsPtr p = NULL,q;
739
740    if (cur == NULL)
741	return(NULL);
742    if (cur->type != XML_NAMESPACE_DECL)
743	return(NULL);
744
745    /*
746     * One can add namespaces only on element nodes
747     */
748    if ((node != NULL) && (node->type != XML_ELEMENT_NODE))
749	node = NULL;
750
751    while (cur != NULL) {
752	if (cur->type != XML_NAMESPACE_DECL)
753	    break;
754
755	/*
756	 * Avoid duplicating namespace declarations in the tree if
757	 * a matching declaration is in scope.
758	 */
759	if (node != NULL) {
760	    if ((node->ns != NULL) &&
761		(xmlStrEqual(node->ns->prefix, cur->prefix)) &&
762        	(xmlStrEqual(node->ns->href, cur->href))) {
763		cur = cur->next;
764		continue;
765	    }
766	    tmp = xmlSearchNs(node->doc, node, cur->prefix);
767	    if ((tmp != NULL) && (xmlStrEqual(tmp->href, cur->href))) {
768		cur = cur->next;
769		continue;
770	    }
771	}
772#ifdef XSLT_REFACTORED
773	/*
774	* Namespace exclusion and ns-aliasing is performed at
775	* compilation-time in the refactored code.
776	*/
777	q = xmlNewNs(node, cur->href, cur->prefix);
778	if (p == NULL) {
779	    ret = p = q;
780	} else {
781	    p->next = q;
782	    p = q;
783	}
784#else
785	/*
786	* TODO: Remove this if the refactored code gets enabled.
787	*/
788	if (!xmlStrEqual(cur->href, XSLT_NAMESPACE)) {
789	    const xmlChar *URI;
790	    /* TODO apply cascading */
791	    URI = (const xmlChar *) xmlHashLookup(ctxt->style->nsAliases,
792		                                  cur->href);
793	    if (URI == UNDEFINED_DEFAULT_NS)
794	        continue;
795	    if (URI != NULL) {
796		q = xmlNewNs(node, URI, cur->prefix);
797	    } else {
798		q = xmlNewNs(node, cur->href, cur->prefix);
799	    }
800	    if (p == NULL) {
801		ret = p = q;
802	    } else {
803		p->next = q;
804		p = q;
805	    }
806	}
807#endif
808	cur = cur->next;
809    }
810    return(ret);
811}
812
813/**
814 * xsltCopyNamespace:
815 * @ctxt:  a transformation context
816 * @elem:  the target element node
817 * @ns:  the namespace node
818 *
819 * Copies a namespace node (declaration). If @elem is not NULL,
820 * then the new namespace will be declared on @elem.
821 *
822 * Returns: a new xmlNsPtr, or NULL in case of an error.
823 */
824xmlNsPtr
825xsltCopyNamespace(xsltTransformContextPtr ctxt ATTRIBUTE_UNUSED,
826		  xmlNodePtr elem, xmlNsPtr ns)
827{
828    if ((ns == NULL) || (ns->type != XML_NAMESPACE_DECL))
829	return(NULL);
830    /*
831     * One can add namespaces only on element nodes
832     */
833    if ((elem != NULL) && (elem->type != XML_ELEMENT_NODE))
834	return(xmlNewNs(NULL, ns->href, ns->prefix));
835    else
836	return(xmlNewNs(elem, ns->href, ns->prefix));
837}
838
839
840/**
841 * xsltFreeNamespaceAliasHashes:
842 * @style: an XSLT stylesheet
843 *
844 * Free up the memory used by namespaces aliases
845 */
846void
847xsltFreeNamespaceAliasHashes(xsltStylesheetPtr style) {
848    if (style->nsAliases != NULL)
849	xmlHashFree((xmlHashTablePtr) style->nsAliases, NULL);
850    style->nsAliases = NULL;
851}
852