namespaces.h File Reference

#include <libxml/tree.h>
#include "xsltexports.h"

Include dependency graph for namespaces.h:

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Go to the source code of this file.

Macros
#define	UNDEFINED_DEFAULT_NS   (const xmlChar *) -1L

Functions
XSLTPUBFUN void XSLTCALL	xsltNamespaceAlias (xsltStylesheetPtr style, xmlNodePtr node)
XSLTPUBFUN xmlNsPtr XSLTCALL	xsltGetNamespace (xsltTransformContextPtr ctxt, xmlNodePtr cur, xmlNsPtr ns, xmlNodePtr out)
XSLTPUBFUN xmlNsPtr XSLTCALL	xsltGetPlainNamespace (xsltTransformContextPtr ctxt, xmlNodePtr cur, xmlNsPtr ns, xmlNodePtr out)
XSLTPUBFUN xmlNsPtr XSLTCALL	xsltGetSpecialNamespace (xsltTransformContextPtr ctxt, xmlNodePtr cur, const xmlChar *URI, const xmlChar *prefix, xmlNodePtr out)
XSLTPUBFUN xmlNsPtr XSLTCALL	xsltCopyNamespace (xsltTransformContextPtr ctxt, xmlNodePtr elem, xmlNsPtr ns)
XSLTPUBFUN xmlNsPtr XSLTCALL	xsltCopyNamespaceList (xsltTransformContextPtr ctxt, xmlNodePtr node, xmlNsPtr cur)
XSLTPUBFUN void XSLTCALL	xsltFreeNamespaceAliasHashes (xsltStylesheetPtr style)

Macro Definition Documentation

UNDEFINED_DEFAULT_NS

#define UNDEFINED_DEFAULT_NS   (const xmlChar *) -1L

UNDEFINED_DEFAULT_NS:

Special value for undefined namespace, internal

Definition at line 30 of file namespaces.h.

Function Documentation

xsltCopyNamespace()

XSLTPUBFUN xmlNsPtr XSLTCALL xsltCopyNamespace	(	xsltTransformContextPtr ctxt	ATTRIBUTE_UNUSED,
		xmlNodePtr	elem,
		xmlNsPtr	ns
	)

xsltCopyNamespace: @ctxt: a transformation context @elem: the target element node @ns: the namespace node

Copies a namespace node (declaration). If @elem is not NULL, then the new namespace will be declared on @elem.

Returns: a new xmlNsPtr, or NULL in case of an error.

Definition at line 809 of file namespaces.c.

{
    if ((ns == NULL) || (ns->type != XML_NAMESPACE_DECL))
    return(NULL);
    /*
     * One can add namespaces only on element nodes
     */
    if ((elem != NULL) && (elem->type != XML_ELEMENT_NODE))
    return(xmlNewNs(NULL, ns->href, ns->prefix));
    else
    return(xmlNewNs(elem, ns->href, ns->prefix));
}

xsltCopyNamespaceList()

XSLTPUBFUN xmlNsPtr XSLTCALL xsltCopyNamespaceList	(	xsltTransformContextPtr	ctxt,
		xmlNodePtr	node,
		xmlNsPtr	cur
	)

xsltCopyNamespaceList: @ctxt: a transformation context @node: the target node @cur: the first namespace

Do a copy of an namespace list. If @node is non-NULL the new namespaces are added automatically. This handles namespaces aliases. This function is intended only for internal use at transformation-time for copying ns-declarations of Literal Result Elements.

Called by: xsltCopyTreeInternal() (transform.c) xsltShallowCopyElem() (transform.c)

REVISIT: This function won't be used in the refactored code.

Returns: a new xmlNsPtr, or NULL in case of error.

Definition at line 717 of file namespaces.c.

                                {
    xmlNsPtr ret = NULL, tmp;
    xmlNsPtr p = NULL,q;
 
    if (cur == NULL)
    return(NULL);
    if (cur->type != XML_NAMESPACE_DECL)
    return(NULL);
 
    /*
     * One can add namespaces only on element nodes
     */
    if ((node != NULL) && (node->type != XML_ELEMENT_NODE))
    node = NULL;
 
    while (cur != NULL) {
    if (cur->type != XML_NAMESPACE_DECL)
        break;
 
    /*
     * Avoid duplicating namespace declarations in the tree if
     * a matching declaration is in scope.
     */
    if (node != NULL) {
        if ((node->ns != NULL) &&
        (xmlStrEqual(node->ns->prefix, cur->prefix)) &&
    (xmlStrEqual(node->ns->href, cur->href))) {
        cur = cur->next;
        continue;
        }
        tmp = xmlSearchNs(node->doc, node, cur->prefix);
        if ((tmp != NULL) && (xmlStrEqual(tmp->href, cur->href))) {
        cur = cur->next;
        continue;
        }
    }
#ifdef XSLT_REFACTORED
    /*
    * Namespace exclusion and ns-aliasing is performed at
    * compilation-time in the refactored code.
    */
    q = xmlNewNs(node, cur->href, cur->prefix);
    if (p == NULL) {
        ret = p = q;
    } else {
        p->next = q;
        p = q;
    }
#else
    /*
    * TODO: Remove this if the refactored code gets enabled.
    */
    if (!xmlStrEqual(cur->href, XSLT_NAMESPACE)) {
        const xmlChar *URI;
        /* TODO apply cascading */
        URI = (const xmlChar *) xmlHashLookup(ctxt->style->nsAliases,
                                          cur->href);
        if (URI == UNDEFINED_DEFAULT_NS) {
        cur = cur->next;
            continue;
        }
        if (URI != NULL) {
        q = xmlNewNs(node, URI, cur->prefix);
        } else {
        q = xmlNewNs(node, cur->href, cur->prefix);
        }
        if (p == NULL) {
        ret = p = q;
        } else {
        p->next = q;
        p = q;
        }
    }
#endif
    cur = cur->next;
    }
    return(ret);
}

Referenced by xsltCopyTree(), and xsltShallowCopyElem().

xsltFreeNamespaceAliasHashes()

XSLTPUBFUN void XSLTCALL xsltFreeNamespaceAliasHashes

(

xsltStylesheetPtr

style

)

xsltFreeNamespaceAliasHashes: @style: an XSLT stylesheet

Free up the memory used by namespaces aliases

Definition at line 831 of file namespaces.c.

                                                      {
    if (style->nsAliases != NULL)
    xmlHashFree((xmlHashTablePtr) style->nsAliases, NULL);
    style->nsAliases = NULL;
}

Referenced by xsltFreeStylesheet().

xsltGetNamespace()

XSLTPUBFUN xmlNsPtr XSLTCALL xsltGetNamespace	(	xsltTransformContextPtr	ctxt,
		xmlNodePtr	cur,
		xmlNsPtr	ns,
		xmlNodePtr	out
	)

xsltGetNamespace: @ctxt: a transformation context @cur: the input node @ns: the namespace @out: the output node (or its parent)

Find a matching (prefix and ns-name) ns-declaration for the requested @ns->prefix and @ns->href in the result tree. If none is found then a new ns-declaration will be added to @resultElem. If, in this case, the given prefix is already in use, then a ns-declaration with a modified ns-prefix be we created.

Called by:

• xsltCopyPropList() (not anymore)
• xsltShallowCopyElement()
• xsltCopyTreeInternal() (not anymore)
• xsltApplySequenceConstructor() (not in the refactored code),
• xsltElement() (not anymore)

Returns a namespace declaration or NULL in case of namespace fixup failures or API or internal errors.

Definition at line 616 of file namespaces.c.

{
 
    if (ns == NULL)
    return(NULL);
 
#ifdef XSLT_REFACTORED
    /*
    * Namespace exclusion and ns-aliasing is performed at
    * compilation-time in the refactored code.
    * Additionally, aliasing is not intended for non Literal
    * Result Elements.
    */
    return(xsltGetSpecialNamespace(ctxt, cur, ns->href, ns->prefix, out));
#else
    {
    xsltStylesheetPtr style;
    const xmlChar *URI = NULL; /* the replacement URI */
 
    if ((ctxt == NULL) || (cur == NULL) || (out == NULL))
        return(NULL);
 
    style = ctxt->style;
    while (style != NULL) {
        if (style->nsAliases != NULL)
        URI = (const xmlChar *)
        xmlHashLookup(style->nsAliases, ns->href);
        if (URI != NULL)
        break;
 
        style = xsltNextImport(style);
    }
 
 
    if (URI == UNDEFINED_DEFAULT_NS) {
        return(xsltGetSpecialNamespace(ctxt, cur, NULL, NULL, out));
#if 0
        /*
        * TODO: Removed, since wrong. If there was no default
        * namespace in the stylesheet then this must resolve to
        * the NULL namespace.
        */
        xmlNsPtr dflt;
        dflt = xmlSearchNs(cur->doc, cur, NULL);
        if (dflt != NULL)
        URI = dflt->href;
        else
        return NULL;
#endif
    } else if (URI == NULL)
        URI = ns->href;
 
    return(xsltGetSpecialNamespace(ctxt, cur, URI, ns->prefix, out));
    }
#endif
}

Referenced by xsltApplySequenceConstructor(), xsltAttrListTemplateProcess(), xsltAttrTemplateProcess(), xsltGetPlainNamespace(), and xsltShallowCopyElem().

xsltGetPlainNamespace()

XSLTPUBFUN xmlNsPtr XSLTCALL xsltGetPlainNamespace	(	xsltTransformContextPtr	ctxt,
		xmlNodePtr	cur,
		xmlNsPtr	ns,
		xmlNodePtr	out
	)

xsltGetPlainNamespace: @ctxt: a transformation context @cur: the input node @ns: the namespace @out: the result element

Obsolete. Not called by any Libxslt/Libexslt function. Exaclty the same as xsltGetNamespace().

Returns a namespace declaration or NULL in case of namespace fixup failures or API or internal errors.

Definition at line 689 of file namespaces.c.

{
    return(xsltGetNamespace(ctxt, cur, ns, out));
}

xsltGetSpecialNamespace()

XSLTPUBFUN xmlNsPtr XSLTCALL xsltGetSpecialNamespace	(	xsltTransformContextPtr	ctxt,
		xmlNodePtr	invocNode,
		const xmlChar *	nsName,
		const xmlChar *	nsPrefix,
		xmlNodePtr	target
	)

xsltGetSpecialNamespace: @ctxt: the transformation context @invocNode: the invoking node; e.g. a literal result element/attr; only used for error reports @nsName: the namespace name (or NULL) @nsPrefix: the suggested namespace prefix (or NULL) @target: the result element on which to anchor a namespace

Find a matching (prefix and ns-name) ns-declaration for the requested @nsName and @nsPrefix in the result tree. If none is found then a new ns-declaration will be added to @resultElem. If, in this case, the given prefix is already in use, then a ns-declaration with a modified ns-prefix be we created. Note that this function's priority is to preserve ns-prefixes; it will only change a prefix if there's a namespace clash. If both @nsName and @nsPrefix are NULL, then this will try to "undeclare" a default namespace by declaring an xmlns="".

Returns a namespace declaration or NULL.

Definition at line 319 of file namespaces.c.

{
    xmlNsPtr ns;
    int prefixOccupied = 0;
 
    if ((ctxt == NULL) || (target == NULL) ||
    (target->type != XML_ELEMENT_NODE))
    return(NULL);
 
    /*
    * NOTE: Namespace exclusion and ns-aliasing is performed at
    *  compilation-time in the refactored code; so this need not be done
    *  here (it was in the old code).
    * NOTE: @invocNode was named @cur in the old code and was documented to
    *  be an input node; since it was only used to anchor an error report
    *  somewhere, we can safely change this to @invocNode, which now
    *  will be the XSLT instruction (also a literal result element/attribute),
    *  which was responsible for this call.
    */
    /*
    * OPTIMIZE TODO: This all could be optimized by keeping track of
    *  the ns-decls currently in-scope via a specialized context.
    */
    if ((nsPrefix == NULL) && ((nsName == NULL) || (nsName[0] == 0))) {
    /*
    * NOTE: the "undeclaration" of the default namespace was
    * part of the logic of the old xsltGetSpecialNamespace() code,
    * so we'll keep that mechanism.
    * Related to the old code: bug #302020:
    */
    /*
    * OPTIMIZE TODO: This all could be optimized by keeping track of
    *  the ns-decls currently in-scope via a specialized context.
    */
    /*
    * Search on the result element itself.
    */
    if (target->nsDef != NULL) {
        ns = target->nsDef;
        do {
        if (ns->prefix == NULL) {
            if ((ns->href != NULL) && (ns->href[0] != 0)) {
            /*
            * Raise a namespace normalization error.
            */
            xsltTransformError(ctxt, NULL, invocNode,
                "Namespace normalization error: Cannot undeclare "
                "the default namespace, since the default namespace "
                "'%s' is already declared on the result element "
                "'%s'.\n", ns->href, target->name);
            return(NULL);
            } else {
            /*
            * The default namespace was undeclared on the
            * result element.
            */
            return(NULL);
            }
            break;
        }
        ns = ns->next;
        } while (ns != NULL);
    }
    if ((target->parent != NULL) &&
        (target->parent->type == XML_ELEMENT_NODE))
    {
        /*
        * The parent element is in no namespace, so assume
        * that there is no default namespace in scope.
        */
        if (target->parent->ns == NULL)
        return(NULL);
 
        ns = xmlSearchNs(target->doc, target->parent,
        NULL);
        /*
        * Fine if there's no default ns is scope, or if the
        * default ns was undeclared.
        */
        if ((ns == NULL) || (ns->href == NULL) || (ns->href[0] == 0))
        return(NULL);
 
        /*
        * Undeclare the default namespace.
        */
        xmlNewNs(target, BAD_CAST "", NULL);
        /* TODO: Check result */
        return(NULL);
    }
    return(NULL);
    }
    /*
    * Handle the XML namespace.
    * QUESTION: Is this faster than using xmlStrEqual() anyway?
    */
    if ((nsPrefix != NULL) &&
    (nsPrefix[0] == 'x') && (nsPrefix[1] == 'm') &&
    (nsPrefix[2] == 'l') && (nsPrefix[3] == 0))
    {
    return(xmlSearchNs(target->doc, target, nsPrefix));
    }
    /*
    * First: search on the result element itself.
    */
    if (target->nsDef != NULL) {
    ns = target->nsDef;
    do {
        if ((ns->prefix == NULL) == (nsPrefix == NULL)) {
        if (ns->prefix == nsPrefix) {
            if (xmlStrEqual(ns->href, nsName))
            return(ns);
            prefixOccupied = 1;
            break;
        } else if (xmlStrEqual(ns->prefix, nsPrefix)) {
            if (xmlStrEqual(ns->href, nsName))
            return(ns);
            prefixOccupied = 1;
            break;
        }
        }
        ns = ns->next;
    } while (ns != NULL);
    }
    if (prefixOccupied) {
    /*
    * If the ns-prefix is occupied by an other ns-decl on the
    * result element, then this means:
    * 1) The desired prefix is shadowed
    * 2) There's no way around changing the prefix
    *
    * Try a desperate search for an in-scope ns-decl
    * with a matching ns-name before we use the last option,
    * which is to recreate the ns-decl with a modified prefix.
    */
    ns = xmlSearchNsByHref(target->doc, target, nsName);
    if (ns != NULL)
        return(ns);
 
    /*
    * Fallback to changing the prefix.
    */
    } else if ((target->parent != NULL) &&
    (target->parent->type == XML_ELEMENT_NODE))
    {
    /*
    * Try to find a matching ns-decl in the ancestor-axis.
    *
    * Check the common case: The parent element of the current
    * result element is in the same namespace (with an equal ns-prefix).
    */
    if ((target->parent->ns != NULL) &&
        ((target->parent->ns->prefix != NULL) == (nsPrefix != NULL)))
    {
        ns = target->parent->ns;
 
        if (nsPrefix == NULL) {
        if (xmlStrEqual(ns->href, nsName))
            return(ns);
        } else if (xmlStrEqual(ns->prefix, nsPrefix) &&
        xmlStrEqual(ns->href, nsName))
        {
        return(ns);
        }
    }
    /*
    * Lookup the remaining in-scope namespaces.
    */
    ns = xmlSearchNs(target->doc, target->parent, nsPrefix);
    if (ns != NULL) {
        if (xmlStrEqual(ns->href, nsName))
        return(ns);
        /*
        * Now check for a nasty case: We need to ensure that the new
        * ns-decl won't shadow a prefix in-use by an existing attribute.
        * <foo xmlns:a="urn:test:a">
        *   <bar a:a="val-a">
        *     <xsl:attribute xmlns:a="urn:test:b" name="a:b">
        *        val-b</xsl:attribute>
        *   </bar>
        * </foo>
        */
        if (target->properties) {
        xmlAttrPtr attr = target->properties;
        do {
            if ((attr->ns) &&
            xmlStrEqual(attr->ns->prefix, nsPrefix))
            {
            /*
            * Bad, this prefix is already in use.
            * Since we'll change the prefix anyway, try
            * a search for a matching ns-decl based on the
            * namespace name.
            */
            ns = xmlSearchNsByHref(target->doc, target, nsName);
            if (ns != NULL)
                return(ns);
            goto declare_new_prefix;
            }
            attr = attr->next;
        } while (attr != NULL);
        }
    } else {
        /*
        * Either no matching ns-prefix was found or the namespace is
        * shadowed.
        * Create a new ns-decl on the current result element.
        *
        * Hmm, we could also try to reuse an in-scope
        * namespace with a matching ns-name but a different
        * ns-prefix.
        * What has higher priority?
        *  1) If keeping the prefix: create a new ns-decl.
        *  2) If reusal: first lookup ns-names; then fallback
        *     to creation of a new ns-decl.
        * REVISIT: this currently uses case 1) although
        *  the old way was use xmlSearchNsByHref() and to let change
        *  the prefix.
        */
#if 0
        ns = xmlSearchNsByHref(target->doc, target, nsName);
        if (ns != NULL)
        return(ns);
#endif
    }
    /*
    * Create the ns-decl on the current result element.
    */
    ns = xmlNewNs(target, nsName, nsPrefix);
    /* TODO: check errors */
    return(ns);
    } else {
    /*
    * This is either the root of the tree or something weird is going on.
    */
    ns = xmlNewNs(target, nsName, nsPrefix);
    /* TODO: Check result */
    return(ns);
    }
 
declare_new_prefix:
    /*
    * Fallback: we need to generate a new prefix and declare the namespace
    * on the result element.
    */
    {
    xmlChar pref[30];
    int counter = 1;
 
    if (nsPrefix == NULL) {
        nsPrefix = BAD_CAST "ns";
    }
 
    do {
        snprintf((char *) pref, 30, "%s_%d", nsPrefix, counter++);
        ns = xmlSearchNs(target->doc, target, BAD_CAST pref);
        if (counter > 1000) {
        xsltTransformError(ctxt, NULL, invocNode,
            "Internal error in xsltAcquireResultInScopeNs(): "
            "Failed to compute a unique ns-prefix for the "
            "generated element");
        return(NULL);
        }
    } while (ns != NULL);
    ns = xmlNewNs(target, nsName, BAD_CAST pref);
    /* TODO: Check result */
    return(ns);
    }
    return(NULL);
}

Referenced by xsltApplySequenceConstructor(), xsltAttribute(), xsltAttrListTemplateProcess(), xsltCopyAttrListNoOverwrite(), xsltCopyTree(), xsltElement(), xsltGetNamespace(), xsltShallowCopyAttr(), and xsltShallowCopyElem().

xsltNamespaceAlias()

XSLTPUBFUN void XSLTCALL xsltNamespaceAlias	(	xsltStylesheetPtr	style,
		xmlNodePtr	node
	)

xsltNamespaceAlias: @style: the XSLT stylesheet @node: the xsl:namespace-alias node

Read the stylesheet-prefix and result-prefix attributes, register them as well as the corresponding namespace.

Definition at line 75 of file namespaces.c.

{
    xmlChar *resultPrefix = NULL;
    xmlChar *stylePrefix = NULL;
    xmlNsPtr literalNs = NULL;
    xmlNsPtr targetNs = NULL;
 
#ifdef XSLT_REFACTORED
    xsltNsAliasPtr alias;
 
    if ((style == NULL) || (node == NULL))
    return;
 
    /*
    * SPEC XSLT 1.0:
    *  "If a namespace URI is declared to be an alias for multiple
    *  different namespace URIs, then the declaration with the highest
    *  import precedence is used. It is an error if there is more than
    *  one such declaration. An XSLT processor may signal the error;
    *  if it does not signal the error, it must recover by choosing,
    *  from amongst the declarations with the highest import precedence,
    *  the one that occurs last in the stylesheet."
    *
    * SPEC TODO: Check for the errors mentioned above.
    */
    /*
    * NOTE that the XSLT 2.0 also *does* use the NULL namespace if
    *  "#default" is used and there's no default namespace is scope.
    *  I.e., this is *not* an error.
    *  Most XSLT 1.0 implementations work this way.
    *  The XSLT 1.0 spec has nothing to say on the subject.
    */
    /*
    * Attribute "stylesheet-prefix".
    */
    stylePrefix = xmlGetNsProp(node, (const xmlChar *)"stylesheet-prefix", NULL);
    if (stylePrefix == NULL) {
    xsltTransformError(NULL, style, node,
        "The attribute 'stylesheet-prefix' is missing.\n");
    return;
    }
    if (xmlStrEqual(stylePrefix, (const xmlChar *)"#default"))
    literalNs = xmlSearchNs(node->doc, node, NULL);
    else {
    literalNs = xmlSearchNs(node->doc, node, stylePrefix);
    if (literalNs == NULL) {
        xsltTransformError(NULL, style, node,
            "Attribute 'stylesheet-prefix': There's no namespace "
        "declaration in scope for the prefix '%s'.\n",
            stylePrefix);
        goto error;
    }
    }
    /*
    * Attribute "result-prefix".
    */
    resultPrefix = xmlGetNsProp(node, (const xmlChar *)"result-prefix", NULL);
    if (resultPrefix == NULL) {
    xsltTransformError(NULL, style, node,
        "The attribute 'result-prefix' is missing.\n");
    goto error;
    }
    if (xmlStrEqual(resultPrefix, (const xmlChar *)"#default"))
    targetNs = xmlSearchNs(node->doc, node, NULL);
    else {
    targetNs = xmlSearchNs(node->doc, node, resultPrefix);
 
        if (targetNs == NULL) {
       xsltTransformError(NULL, style, node,
            "Attribute 'result-prefix': There's no namespace "
        "declaration in scope for the prefix '%s'.\n",
            stylePrefix);
        goto error;
    }
    }
    /*
     *
     * Same alias for multiple different target namespace URIs:
     *  TODO: The one with the highest import precedence is used.
     *  Example:
     *  <xsl:namespace-alias stylesheet-prefix="foo"
     *                       result-prefix="bar"/>
     *
     *  <xsl:namespace-alias stylesheet-prefix="foo"
     *                       result-prefix="zar"/>
     *
     * Same target namespace URI for multiple different aliases:
     *  All alias-definitions will be used.
     *  Example:
     *  <xsl:namespace-alias stylesheet-prefix="bar"
     *                       result-prefix="foo"/>
     *
     *  <xsl:namespace-alias stylesheet-prefix="zar"
     *                       result-prefix="foo"/>
     * Cases using #default:
     *  <xsl:namespace-alias stylesheet-prefix="#default"
     *                       result-prefix="#default"/>
     *  TODO: Has this an effect at all?
     *
     *  <xsl:namespace-alias stylesheet-prefix="foo"
     *                       result-prefix="#default"/>
     *  From namespace to no namespace.
     *
     *  <xsl:namespace-alias stylesheet-prefix="#default"
     *                       result-prefix="foo"/>
     *  From no namespace to namespace.
     */
 
 
     /*
     * Store the ns-node in the alias-object.
    */
    alias = xsltNewNsAlias(XSLT_CCTXT(style));
    if (alias == NULL)
    return;
    alias->literalNs = literalNs;
    alias->targetNs = targetNs;
    XSLT_CCTXT(style)->hasNsAliases = 1;
 
 
#else /* XSLT_REFACTORED */
    const xmlChar *literalNsName;
    const xmlChar *targetNsName;
 
 
    if ((style == NULL) || (node == NULL))
    return;
 
    stylePrefix = xmlGetNsProp(node, (const xmlChar *)"stylesheet-prefix", NULL);
    if (stylePrefix == NULL) {
    xsltTransformError(NULL, style, node,
        "namespace-alias: stylesheet-prefix attribute missing\n");
    return;
    }
    resultPrefix = xmlGetNsProp(node, (const xmlChar *)"result-prefix", NULL);
    if (resultPrefix == NULL) {
    xsltTransformError(NULL, style, node,
        "namespace-alias: result-prefix attribute missing\n");
    goto error;
    }
 
    if (xmlStrEqual(stylePrefix, (const xmlChar *)"#default")) {
    literalNs = xmlSearchNs(node->doc, node, NULL);
    if (literalNs == NULL) {
        literalNsName = NULL;
    } else
        literalNsName = literalNs->href; /* Yes - set for nsAlias table */
    } else {
    literalNs = xmlSearchNs(node->doc, node, stylePrefix);
 
    if ((literalNs == NULL) || (literalNs->href == NULL)) {
        xsltTransformError(NULL, style, node,
            "namespace-alias: prefix %s not bound to any namespace\n",
                    stylePrefix);
        goto error;
    } else
        literalNsName = literalNs->href;
    }
 
    /*
     * When "#default" is used for result, if a default namespace has not
     * been explicitly declared the special value UNDEFINED_DEFAULT_NS is
     * put into the nsAliases table
     */
    if (xmlStrEqual(resultPrefix, (const xmlChar *)"#default")) {
    targetNs = xmlSearchNs(node->doc, node, NULL);
    if (targetNs == NULL) {
        targetNsName = UNDEFINED_DEFAULT_NS;
    } else
        targetNsName = targetNs->href;
    } else {
    targetNs = xmlSearchNs(node->doc, node, resultPrefix);
 
        if ((targetNs == NULL) || (targetNs->href == NULL)) {
        xsltTransformError(NULL, style, node,
            "namespace-alias: prefix %s not bound to any namespace\n",
                    resultPrefix);
        goto error;
    } else
        targetNsName = targetNs->href;
    }
    /*
     * Special case: if #default is used for
     *  the stylesheet-prefix (literal namespace) and there's no default
     *  namespace in scope, we'll use style->defaultAlias for this.
     */
    if (literalNsName == NULL) {
        if (targetNs != NULL) {
        /*
        * BUG TODO: Is it not sufficient to have only 1 field for
        *  this, since subsequently alias declarations will
        *  overwrite this.
        *  Example:
        *   <xsl:namespace-alias result-prefix="foo"
        *                        stylesheet-prefix="#default"/>
        *   <xsl:namespace-alias result-prefix="bar"
        *                        stylesheet-prefix="#default"/>
        *  The mapping for "foo" won't be visible anymore.
        */
            style->defaultAlias = targetNs->href;
    }
    } else {
        if (style->nsAliases == NULL)
        style->nsAliases = xmlHashCreate(10);
        if (style->nsAliases == NULL) {
        xsltTransformError(NULL, style, node,
            "namespace-alias: cannot create hash table\n");
        goto error;
        }
    xmlHashAddEntry((xmlHashTablePtr) style->nsAliases,
        literalNsName, (void *) targetNsName);
    }
#endif /* else of XSLT_REFACTORED */
 
error:
    if (stylePrefix != NULL)
    xmlFree(stylePrefix);
    if (resultPrefix != NULL)
    xmlFree(resultPrefix);
}

Referenced by xsltParseStylesheetTop().