xinclude.c

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 *									*
 *			XInclude Processing				*
 *									*
 ************************************************************************/

/**
 * xmlXIncludePreProcessNode:
 * @ctxt: an XInclude context
 * @node: an XInclude node
 *
 * Implement the XInclude preprocessing, currently just adding the element
 * for further processing.
 *
 * Returns the result list or NULL in case of error
 */
static xmlNodePtr
xmlXIncludePreProcessNode(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node) {
    xmlXIncludeAddNode(ctxt, node);
    return(0);
}

/**
 * xmlXIncludeLoadNode:
 * @ctxt: an XInclude context
 * @nr: the node number
 *
 * Find and load the infoset replacement for the given node.
 *
 * Returns 0 if substitution succeeded, -1 if some processing failed
 */
static int
xmlXIncludeLoadNode(xmlXIncludeCtxtPtr ctxt, int nr) {
    xmlNodePtr cur;
    xmlChar *href;
    xmlChar *parse;
    xmlChar *base;
    xmlChar *oldBase;
    xmlChar *URI;
    int xml = 1; /* default Issue 64 */
    int ret;

    if (ctxt == NULL)
	return(-1);
    if ((nr < 0) || (nr >= ctxt->incNr))
	return(-1);
    cur = ctxt->incTab[nr]->ref;
    if (cur == NULL)
	return(-1);

    /*
     * read the attributes
     */
    href = xmlXIncludeGetProp(ctxt, cur, XINCLUDE_HREF);
    if (href == NULL) {
	href = xmlStrdup(BAD_CAST ""); /* @@@@ href is now optional */
	if (href == NULL) 
	    return(-1);
    }
    parse = xmlXIncludeGetProp(ctxt, cur, XINCLUDE_PARSE);
    if (parse != NULL) {
	if (xmlStrEqual(parse, XINCLUDE_PARSE_XML))
	    xml = 1;
	else if (xmlStrEqual(parse, XINCLUDE_PARSE_TEXT))
	    xml = 0;
	else {
	    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
	                   XML_XINCLUDE_PARSE_VALUE,
			   "invalid value %s for 'parse'\n", parse);
	    if (href != NULL)
		xmlFree(href);
	    if (parse != NULL)
		xmlFree(parse);
	    return(-1);
	}
    }

    /*
     * compute the URI
     */
    base = xmlNodeGetBase(ctxt->doc, cur);
    if (base == NULL) {
	URI = xmlBuildURI(href, ctxt->doc->URL);
    } else {
	URI = xmlBuildURI(href, base);
    }
    if (URI == NULL) {
	xmlChar *escbase;
	xmlChar *eschref;
	/*
	 * Some escaping may be needed
	 */
	escbase = xmlURIEscape(base);
	eschref = xmlURIEscape(href);
	URI = xmlBuildURI(eschref, escbase);
	if (escbase != NULL)
	    xmlFree(escbase);
	if (eschref != NULL)
	    xmlFree(eschref);
    }
    if (URI == NULL) {
	xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
	               XML_XINCLUDE_HREF_URI, "failed build URL\n", NULL);
	if (parse != NULL)
	    xmlFree(parse);
	if (href != NULL)
	    xmlFree(href);
	if (base != NULL)
	    xmlFree(base);
	return(-1);
    }
#ifdef DEBUG_XINCLUDE
    xmlGenericError(xmlGenericErrorContext, "parse: %s\n",
	    xml ? "xml": "text");
    xmlGenericError(xmlGenericErrorContext, "URI: %s\n", URI);
#endif

    /*
     * Save the base for this include (saving the current one)
     */
    oldBase = ctxt->base;
    ctxt->base = base;

    if (xml) {
	ret = xmlXIncludeLoadDoc(ctxt, URI, nr);
	/* xmlXIncludeGetFragment(ctxt, cur, URI); */
    } else {
	ret = xmlXIncludeLoadTxt(ctxt, URI, nr);
    }

    /*
     * Restore the original base before checking for fallback
     */
    ctxt->base = oldBase;
    
    if (ret < 0) {
	xmlNodePtr children;

	/*
	 * Time to try a fallback if availble
	 */
#ifdef DEBUG_XINCLUDE
	xmlGenericError(xmlGenericErrorContext, "error looking for fallback\n");
#endif
	children = cur->children;
	while (children != NULL) {
	    if ((children->type == XML_ELEMENT_NODE) &&
		(children->ns != NULL) &&
		(xmlStrEqual(children->name, XINCLUDE_FALLBACK)) &&
		((xmlStrEqual(children->ns->href, XINCLUDE_NS)) ||
		 (xmlStrEqual(children->ns->href, XINCLUDE_OLD_NS)))) {
		ret = xmlXIncludeLoadFallback(ctxt, children, nr);
		if (ret == 0) 
		    break;
	    }
	    children = children->next;
	}
    }
    if (ret < 0) {
	xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
	               XML_XINCLUDE_NO_FALLBACK,
		       "could not load %s, and no fallback was found\n",
		       URI);
    }

    /*
     * Cleanup
     */
    if (URI != NULL)
	xmlFree(URI);
    if (parse != NULL)
	xmlFree(parse);
    if (href != NULL)
	xmlFree(href);
    if (base != NULL)
	xmlFree(base);
    return(0);
}

/**
 * xmlXIncludeIncludeNode:
 * @ctxt: an XInclude context
 * @nr: the node number
 *
 * Inplement the infoset replacement for the given node
 *
 * Returns 0 if substitution succeeded, -1 if some processing failed
 */
static int
xmlXIncludeIncludeNode(xmlXIncludeCtxtPtr ctxt, int nr) {
    xmlNodePtr cur, end, list, tmp;

    if (ctxt == NULL)
	return(-1);
    if ((nr < 0) || (nr >= ctxt->incNr))
	return(-1);
    cur = ctxt->incTab[nr]->ref;
    if (cur == NULL)
	return(-1);

    /*
     * If we stored an XPointer a late computation may be needed
     */
    if ((ctxt->incTab[nr]->inc == NULL) &&
	(ctxt->incTab[nr]->xptr != NULL)) {
	ctxt->incTab[nr]->inc =
	    xmlXIncludeCopyXPointer(ctxt, ctxt->doc, ctxt->doc,
		                    ctxt->incTab[nr]->xptr);
	xmlXPathFreeObject(ctxt->incTab[nr]->xptr);
	ctxt->incTab[nr]->xptr = NULL;
    }
    list = ctxt->incTab[nr]->inc;
    ctxt->incTab[nr]->inc = NULL;

    /*
     * Check against the risk of generating a multi-rooted document
     */
    if ((cur->parent != NULL) &&
	(cur->parent->type != XML_ELEMENT_NODE)) {
	int nb_elem = 0;

	tmp = list;
	while (tmp != NULL) {
	    if (tmp->type == XML_ELEMENT_NODE)
		nb_elem++;
	    tmp = tmp->next;
	}
	if (nb_elem > 1) {
	    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
	                   XML_XINCLUDE_MULTIPLE_ROOT,
		       "XInclude error: would result in multiple root nodes\n",
			   NULL);
	    return(-1);
	}
    }

    if (ctxt->parseFlags & XML_PARSE_NOXINCNODE) {
	/*
	 * Add the list of nodes
	 */
	while (list != NULL) {
	    end = list;
	    list = list->next;

	    xmlAddPrevSibling(cur, end);
	}
	xmlUnlinkNode(cur);
	xmlFreeNode(cur);
    } else {
	/*
	 * Change the current node as an XInclude start one, and add an
	 * XInclude end one
	 */
	cur->type = XML_XINCLUDE_START;
	end = xmlNewDocNode(cur->doc, cur->ns, cur->name, NULL);
	if (end == NULL) {
	    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
	                   XML_XINCLUDE_BUILD_FAILED,
			   "failed to build node\n", NULL);
	    return(-1);
	}
	end->type = XML_XINCLUDE_END;
	xmlAddNextSibling(cur, end);

	/*
	 * Add the list of nodes
	 */
	while (list != NULL) {
	    cur = list;
	    list = list->next;

	    xmlAddPrevSibling(end, cur);
	}
    }

    
    return(0);
}

/**
 * xmlXIncludeTestNode:
 * @ctxt: the XInclude processing context
 * @node: an XInclude node
 *
 * test if the node is an XInclude node
 *
 * Returns 1 true, 0 otherwise
 */
static int
xmlXIncludeTestNode(xmlXIncludeCtxtPtr ctxt, xmlNodePtr node) {
    if (node == NULL)
	return(0);
    if (node->type != XML_ELEMENT_NODE)
	return(0);
    if (node->ns == NULL)
	return(0);
    if ((xmlStrEqual(node->ns->href, XINCLUDE_NS)) ||
        (xmlStrEqual(node->ns->href, XINCLUDE_OLD_NS))) {
	if (xmlStrEqual(node->ns->href, XINCLUDE_OLD_NS)) {
	    if (ctxt->legacy == 0) {
#if 0 /* wait for the XML Core Working Group to get something stable ! */
		xmlXIncludeWarn(ctxt, node, XML_XINCLUDE_DEPRECATED_NS,
	               "Deprecated XInclude namespace found, use %s",
		                XINCLUDE_NS);
#endif
	        ctxt->legacy = 1;
	    }
	}
	if (xmlStrEqual(node->name, XINCLUDE_NODE)) {
	    xmlNodePtr child = node->children;
	    int nb_fallback = 0;

	    while (child != NULL) {
		if ((child->type == XML_ELEMENT_NODE) &&
		    (child->ns != NULL) &&
		    ((xmlStrEqual(child->ns->href, XINCLUDE_NS)) ||
		     (xmlStrEqual(child->ns->href, XINCLUDE_OLD_NS)))) {
		    if (xmlStrEqual(child->name, XINCLUDE_NODE)) {
			xmlXIncludeErr(ctxt, node,
			               XML_XINCLUDE_INCLUDE_IN_INCLUDE,
				       "%s has an 'include' child\n",
				       XINCLUDE_NODE);
			return(0);
		    }
		    if (xmlStrEqual(child->name, XINCLUDE_FALLBACK)) {
			nb_fallback++;
		    }
		}
		child = child->next;
	    }
	    if (nb_fallback > 1) {
		xmlXIncludeErr(ctxt, node, XML_XINCLUDE_FALLBACKS_IN_INCLUDE,
			       "%s has multiple fallback children\n",
		               XINCLUDE_NODE);
		return(0);
	    }
	    return(1);
	}
	if (xmlStrEqual(node->name, XINCLUDE_FALLBACK)) {
	    if ((node->parent == NULL) ||
		(node->parent->type != XML_ELEMENT_NODE) ||
		(node->parent->ns == NULL) ||
		((!xmlStrEqual(node->parent->ns->href, XINCLUDE_NS)) &&
		 (!xmlStrEqual(node->parent->ns->href, XINCLUDE_OLD_NS))) ||
		(!xmlStrEqual(node->parent->name, XINCLUDE_NODE))) {
		xmlXIncludeErr(ctxt, node,
		               XML_XINCLUDE_FALLBACK_NOT_IN_INCLUDE,
			       "%s is not the child of an 'include'\n",
			       XINCLUDE_FALLBACK);
	    }
	}
    }
    return(0);
}

/**
 * xmlXIncludeDoProcess:
 * @ctxt: the XInclude processing context
 * @doc: an XML document
 * @tree: the top of the tree to process
 *
 * Implement the XInclude substitution on the XML document @doc
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
static int
xmlXIncludeDoProcess(xmlXIncludeCtxtPtr ctxt, xmlDocPtr doc, xmlNodePtr tree) {
    xmlNodePtr cur;
    int ret = 0;
    int i;

    if ((doc == NULL) || (tree == NULL))
	return(-1);
    if (ctxt == NULL)
	return(-1);

    if (doc->URL != NULL) {
	ret = xmlXIncludeURLPush(ctxt, doc->URL);
	if (ret < 0)
	    return(-1);
    }

    /*
     * First phase: lookup the elements in the document
     */
    cur = tree;
    if (xmlXIncludeTestNode(ctxt, cur) == 1)
	xmlXIncludePreProcessNode(ctxt, cur);
    while ((cur != NULL) && (cur != tree->parent)) {
	/* TODO: need to work on entities -> stack */
	if ((cur->children != NULL) &&
	    (cur->children->type != XML_ENTITY_DECL) &&
	    (cur->children->type != XML_XINCLUDE_START) &&
	    (cur->children->type != XML_XINCLUDE_END)) {
	    cur = cur->children;
	    if (xmlXIncludeTestNode(ctxt, cur))
		xmlXIncludePreProcessNode(ctxt, cur);
	} else if (cur->next != NULL) {
	    cur = cur->next;
	    if (xmlXIncludeTestNode(ctxt, cur))
		xmlXIncludePreProcessNode(ctxt, cur);
	} else {
	    if (cur == tree)
	        break;
	    do {
		cur = cur->parent;
		if ((cur == NULL) || (cur == tree->parent))
		    break; /* do */
		if (cur->next != NULL) {
		    cur = cur->next;
		    if (xmlXIncludeTestNode(ctxt, cur))
			xmlXIncludePreProcessNode(ctxt, cur);
		    break; /* do */
		}
	    } while (cur != NULL);
	}
    }

    /*
     * Second Phase : collect the infosets fragments
     */
    for (i = ctxt->incBase;i < ctxt->incNr; i++) {
        xmlXIncludeLoadNode(ctxt, i);
	ret++;
    }

    /*
     * Third phase: extend the original document infoset.
     *
     * Originally we bypassed the inclusion if there were any errors
     * encountered on any of the XIncludes.  A bug was raised (bug
     * 132588) requesting that we output the XIncludes without error,
     * so the check for inc!=NULL || xptr!=NULL was put in.  This may
     * give some other problems in the future, but for now it seems to
     * work ok.
     *
     */
    for (i = ctxt->incBase;i < ctxt->incNr; i++) {
	if ((ctxt->incTab[i]->inc != NULL) ||
		(ctxt->incTab[i]->xptr != NULL) ||
		(ctxt->incTab[i]->emptyFb != 0))	/* (empty fallback) */
	    xmlXIncludeIncludeNode(ctxt, i);
    }

    if (doc->URL != NULL)
	xmlXIncludeURLPop(ctxt);
    return(ret);
}

/**
 * xmlXIncludeSetFlags:
 * @ctxt:  an XInclude processing context
 * @flags: a set of xmlParserOption used for parsing XML includes
 *
 * Set the flags used for further processing of XML resources.
 *
 * Returns 0 in case of success and -1 in case of error.
 */
int
xmlXIncludeSetFlags(xmlXIncludeCtxtPtr ctxt, int flags) {
    if (ctxt == NULL)
        return(-1);
    ctxt->parseFlags = flags;
    return(0);
}
 
/**
 * xmlXIncludeProcessFlags:
 * @doc: an XML document
 * @flags: a set of xmlParserOption used for parsing XML includes
 *
 * Implement the XInclude substitution on the XML document @doc
 *
 * Returns 0 if no substitution were done, -1 if some processing failed
 *    or the number of substitutions done.
 */
int
xmlXIncludeProcessFlags(xmlDocPtr doc, int flags) {
    xmlXIncludeCtxtPtr ctxt;
    xmlNodePtr tree