/*
* namespaces.c: Implementation of the XSLT namespaces handling
*
* Reference:
* http://www.w3.org/TR/1999/REC-xslt-19991116
*
* See Copyright for the status of this software.
*
* daniel@veillard.com
*/
#include "precomp.h"
/************************************************************************
* *
* Module interfaces *
* *
************************************************************************/
#ifdef XSLT_REFACTORED
static xsltNsAliasPtr
xsltNewNsAlias(xsltCompilerCtxtPtr cctxt)
{
xsltNsAliasPtr ret;
if (cctxt == NULL)
return(NULL);
ret = (xsltNsAliasPtr) xmlMalloc(sizeof(xsltNsAlias));
if (ret == NULL) {
xsltTransformError(NULL, cctxt->style, NULL,
"Internal error in xsltNewNsAlias(): Memory allocation failed.\n");
cctxt->style->errors++;
return(NULL);
}
memset(ret, 0, sizeof(xsltNsAlias));
/*
* TODO: Store the item at current stylesheet-level.
*/
ret->next = cctxt->nsAliases;
cctxt->nsAliases = ret;
return(ret);
}
#endif /* XSLT_REFACTORED */
/**
* 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.
*/
void
xsltNamespaceAlias(xsltStylesheetPtr style, xmlNodePtr node)
{
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:
*
*
*
*
* Same target namespace URI for multiple different aliases:
* All alias-definitions will be used.
* Example:
*
*
*
* Cases using #default:
*
* TODO: Has this an effect at all?
*
*
* From namespace to no namespace.
*
*
* 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:
*
*
* 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);
}
/**
* 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.
*/
xmlNsPtr
xsltGetSpecialNamespace(xsltTransformContextPtr ctxt, xmlNodePtr invocNode,
const xmlChar *nsName, const xmlChar *nsPrefix,
xmlNodePtr target)
{
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.
*
*
*
* val-b
*
*
*/
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);
}
/**
* 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.
*/
xmlNsPtr
xsltGetNamespace(xsltTransformContextPtr ctxt, xmlNodePtr cur, xmlNsPtr ns,
xmlNodePtr out)
{
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
}
/**
* 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.
*/
xmlNsPtr
xsltGetPlainNamespace(xsltTransformContextPtr ctxt, xmlNodePtr cur,
xmlNsPtr ns, xmlNodePtr out)
{
return(xsltGetNamespace(ctxt, cur, ns, out));
}
/**
* 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.
*/
xmlNsPtr
xsltCopyNamespaceList(xsltTransformContextPtr ctxt, xmlNodePtr node,
xmlNsPtr cur) {
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);
}
/**
* 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.
*/
xmlNsPtr
xsltCopyNamespace(xsltTransformContextPtr ctxt ATTRIBUTE_UNUSED,
xmlNodePtr elem, xmlNsPtr ns)
{
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));
}
/**
* xsltFreeNamespaceAliasHashes:
* @style: an XSLT stylesheet
*
* Free up the memory used by namespaces aliases
*/
void
xsltFreeNamespaceAliasHashes(xsltStylesheetPtr style) {
if (style->nsAliases != NULL)
xmlHashFree((xmlHashTablePtr) style->nsAliases, NULL);
style->nsAliases = NULL;
}