xinclude.c

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    doc = xmlXIncludeParseFile(ctxt, (const char *)URL);
#ifdef LIBXML_XPTR_ENABLED
    ctxt->parseFlags = saveFlags;
#endif
    if (doc == NULL) {
	xmlFree(URL);
	if (fragment != NULL)
	    xmlFree(fragment);
	return(-1);
    }
    ctxt->incTab[nr]->doc = doc;
    /*
     * It's possible that the requested URL has been mapped to a
     * completely different location (e.g. through a catalog entry).
     * To check for this, we compare the URL with that of the doc
     * and change it if they disagree (bug 146988).
     */
   if (!xmlStrEqual(URL, doc->URL)) {
       xmlFree(URL);
       URL = xmlStrdup(doc->URL);
   }
    for (i = nr + 1; i < ctxt->incNr; i++) {
	if (xmlStrEqual(URL, ctxt->incTab[i]->URI)) {
	    ctxt->incTab[nr]->count++;
#ifdef DEBUG_XINCLUDE
	    printf("Increasing %s count since reused\n", URL);
#endif
            break;
	}
    }

    /*
     * Make sure we have all entities fixed up
     */
    xmlXIncludeMergeEntities(ctxt, ctxt->doc, doc);

    /*
     * We don't need the DTD anymore, free up space
    if (doc->intSubset != NULL) {
	xmlUnlinkNode((xmlNodePtr) doc->intSubset);
	xmlFreeNode((xmlNodePtr) doc->intSubset);
	doc->intSubset = NULL;
    }
    if (doc->extSubset != NULL) {
	xmlUnlinkNode((xmlNodePtr) doc->extSubset);
	xmlFreeNode((xmlNodePtr) doc->extSubset);
	doc->extSubset = NULL;
    }
     */
    xmlXIncludeRecurseDoc(ctxt, doc, URL);

loaded:
    if (fragment == NULL) {
	/*
	 * Add the top children list as the replacement copy.
	 */
	if (doc == NULL)
	{
	    /* Hopefully a DTD declaration won't be copied from
	     * the same document */
	    ctxt->incTab[nr]->inc = xmlCopyNodeList(ctxt->doc->children);
	} else {
	    ctxt->incTab[nr]->inc = xmlXIncludeCopyNodeList(ctxt, ctxt->doc,
		                                       doc, doc->children);
	}
    } 
#ifdef LIBXML_XPTR_ENABLED
    else {
	/*
	 * Computes the XPointer expression and make a copy used
	 * as the replacement copy.
	 */
	xmlXPathObjectPtr xptr;
	xmlXPathContextPtr xptrctxt;
	xmlNodeSetPtr set;

	if (doc == NULL) {
	    xptrctxt = xmlXPtrNewContext(ctxt->doc, ctxt->incTab[nr]->ref,
		                         NULL);
	} else {
	    xptrctxt = xmlXPtrNewContext(doc, NULL, NULL);
	}
	if (xptrctxt == NULL) {
	    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
	                   XML_XINCLUDE_XPTR_FAILED,
			   "could not create XPointer context\n", NULL);
	    xmlFree(URL);
	    xmlFree(fragment);
	    return(-1);
	}
	xptr = xmlXPtrEval(fragment, xptrctxt);
	if (xptr == NULL) {
	    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
	                   XML_XINCLUDE_XPTR_FAILED,
			   "XPointer evaluation failed: #%s\n",
			   fragment);
	    xmlXPathFreeContext(xptrctxt);
	    xmlFree(URL);
	    xmlFree(fragment);
	    return(-1);
	}
	switch (xptr->type) {
	    case XPATH_UNDEFINED:
	    case XPATH_BOOLEAN:
	    case XPATH_NUMBER:
	    case XPATH_STRING:
	    case XPATH_POINT:
	    case XPATH_USERS:
	    case XPATH_XSLT_TREE:
		xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
		               XML_XINCLUDE_XPTR_RESULT,
			       "XPointer is not a range: #%s\n",
			       fragment);
		xmlXPathFreeContext(xptrctxt);
		xmlFree(URL);
		xmlFree(fragment);
		return(-1);
	    case XPATH_NODESET:
	        if ((xptr->nodesetval == NULL) ||
		    (xptr->nodesetval->nodeNr <= 0)) {
		    xmlXPathFreeContext(xptrctxt);
		    xmlFree(URL);
		    xmlFree(fragment);
		    return(-1);
		}

	    case XPATH_RANGE:
	    case XPATH_LOCATIONSET:
		break;
	}
	set = xptr->nodesetval;
	if (set != NULL) {
	    for (i = 0;i < set->nodeNr;i++) {
		if (set->nodeTab[i] == NULL)
		    continue;
		switch (set->nodeTab[i]->type) {
		    case XML_TEXT_NODE:
		    case XML_CDATA_SECTION_NODE:
		    case XML_ENTITY_REF_NODE:
		    case XML_ENTITY_NODE:
		    case XML_PI_NODE:
		    case XML_COMMENT_NODE:
		    case XML_DOCUMENT_NODE:
		    case XML_HTML_DOCUMENT_NODE:
#ifdef LIBXML_DOCB_ENABLED
		    case XML_DOCB_DOCUMENT_NODE:
#endif
			continue;
		    case XML_ELEMENT_NODE: {
			xmlChar *nodeBase;
			xmlNodePtr el = set->nodeTab[i];

			nodeBase = xmlNodeGetBase(el->doc, el);
			if (nodeBase != NULL) {
			    if (!xmlStrEqual(nodeBase, el->doc->URL))
			        xmlNodeSetBase(el, nodeBase);
			    xmlFree(nodeBase);
			}
			continue;
		    }

		    case XML_ATTRIBUTE_NODE:
			xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
			               XML_XINCLUDE_XPTR_RESULT,
				       "XPointer selects an attribute: #%s\n",
				       fragment);
			set->nodeTab[i] = NULL;
			continue;
		    case XML_NAMESPACE_DECL:
			xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
			               XML_XINCLUDE_XPTR_RESULT,
				       "XPointer selects a namespace: #%s\n",
				       fragment);
			set->nodeTab[i] = NULL;
			continue;
		    case XML_DOCUMENT_TYPE_NODE:
		    case XML_DOCUMENT_FRAG_NODE:
		    case XML_NOTATION_NODE:
		    case XML_DTD_NODE:
		    case XML_ELEMENT_DECL:
		    case XML_ATTRIBUTE_DECL:
		    case XML_ENTITY_DECL:
		    case XML_XINCLUDE_START:
		    case XML_XINCLUDE_END:
			xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
			               XML_XINCLUDE_XPTR_RESULT,
				   "XPointer selects unexpected nodes: #%s\n",
				       fragment);
			set->nodeTab[i] = NULL;
			set->nodeTab[i] = NULL;
			continue; /* for */
		}
	    }
	}
	if (doc == NULL) {
	    ctxt->incTab[nr]->xptr = xptr;
	    ctxt->incTab[nr]->inc = NULL;
	} else {
	    ctxt->incTab[nr]->inc =
		xmlXIncludeCopyXPointer(ctxt, ctxt->doc, doc, xptr);
	    xmlXPathFreeObject(xptr);
	}
	xmlXPathFreeContext(xptrctxt);
	xmlFree(fragment);
    }
#endif

    /*
     * Do the xml:base fixup if needed
     */
    if ((doc != NULL) && (URL != NULL) && (xmlStrchr(URL, (xmlChar) '/'))) {
	xmlNodePtr node;
	xmlChar *base;
	xmlChar *curBase;

	/*
	 * The base is only adjusted if "necessary", i.e. if the xinclude node
	 * has a base specified, or the URL is relative
	 */
	base = xmlGetNsProp(ctxt->incTab[nr]->ref, BAD_CAST "base",
			XML_XML_NAMESPACE);
	if (base == NULL) {
	    /*
	     * No xml:base on the xinclude node, so we check whether the
	     * URI base is different than (relative to) the context base
	     */
	    curBase = xmlBuildRelativeURI(URL, ctxt->base);
	    if (curBase == NULL) {	/* Error return */
	        xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
	               XML_XINCLUDE_HREF_URI,
		       "trying to build relative URI from %s\n", URL);
	    } else {
		/* If the URI doesn't contain a slash, it's not relative */
	        if (!xmlStrchr(curBase, (xmlChar) '/'))
		    xmlFree(curBase);
		else
		    base = curBase;
	    }
	}
	if (base != NULL) {	/* Adjustment may be needed */
	    node = ctxt->incTab[nr]->inc;
	    while (node != NULL) {
		/* Only work on element nodes */
		if (node->type == XML_ELEMENT_NODE) {
		    curBase = xmlNodeGetBase(node->doc, node);
		    /* If no current base, set it */
		    if (curBase == NULL) {
			xmlNodeSetBase(node, base);
		    } else {
			/*
			 * If the current base is the same as the
			 * URL of the document, then reset it to be
			 * the specified xml:base or the relative URI
			 */
			if (xmlStrEqual(curBase, node->doc->URL)) {
			    xmlNodeSetBase(node, base);
			} else {
			    /*
			     * If the element already has an xml:base
			     * set, then relativise it if necessary
			     */
			    xmlChar *xmlBase;
			    xmlBase = xmlGetNsProp(node,
					    BAD_CAST "base",
					    XML_XML_NAMESPACE);
			    if (xmlBase != NULL) {
				xmlChar *relBase;
				relBase = xmlBuildURI(xmlBase, base);
				if (relBase == NULL) { /* error */
				    xmlXIncludeErr(ctxt, 
						ctxt->incTab[nr]->ref,
						XML_XINCLUDE_HREF_URI,
					"trying to rebuild base from %s\n",
						xmlBase);
				} else {
				    xmlNodeSetBase(node, relBase);
				    xmlFree(relBase);
				}
				xmlFree(xmlBase);
			    }
			}
			xmlFree(curBase);
		    }
		}
	        node = node->next;
	    }
	    xmlFree(base);
	}
    }
    if ((nr < ctxt->incNr) && (ctxt->incTab[nr]->doc != NULL) &&
	(ctxt->incTab[nr]->count <= 1)) {
#ifdef DEBUG_XINCLUDE
        printf("freeing %s\n", ctxt->incTab[nr]->doc->URL);
#endif
	xmlFreeDoc(ctxt->incTab[nr]->doc);
	ctxt->incTab[nr]->doc = NULL;
    }
    xmlFree(URL);
    return(0);
}

/**
 * xmlXIncludeLoadTxt:
 * @ctxt:  the XInclude context
 * @url:  the associated URL
 * @nr:  the xinclude node number
 * 
 * Load the content, and store the result in the XInclude context
 *
 * Returns 0 in case of success, -1 in case of failure
 */
static int
xmlXIncludeLoadTxt(xmlXIncludeCtxtPtr ctxt, const xmlChar *url, int nr) {
    xmlParserInputBufferPtr buf;
    xmlNodePtr node;
    xmlURIPtr uri;
    xmlChar *URL;
    int i;
    xmlChar *encoding = NULL;
    xmlCharEncoding enc = (xmlCharEncoding) 0;

    /*
     * Check the URL and remove any fragment identifier
     */
    uri = xmlParseURI((const char *)url);
    if (uri == NULL) {
	xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, XML_XINCLUDE_HREF_URI,
	               "invalid value URI %s\n", url);
	return(-1);
    }
    if (uri->fragment != NULL) {
	xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, XML_XINCLUDE_TEXT_FRAGMENT,
	               "fragment identifier forbidden for text: %s\n",
		       (const xmlChar *) uri->fragment);
	xmlFreeURI(uri);
	return(-1);
    }
    URL = xmlSaveUri(uri);
    xmlFreeURI(uri);
    if (URL == NULL) {
	xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, XML_XINCLUDE_HREF_URI,
	               "invalid value URI %s\n", url);
	return(-1);
    }

    /*
     * Handling of references to the local document are done
     * directly through ctxt->doc.
     */
    if (URL[0] == 0) {
	xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref, 
	               XML_XINCLUDE_TEXT_DOCUMENT,
		       "text serialization of document not available\n", NULL);
	xmlFree(URL);
	return(-1);
    }

    /*
     * Prevent reloading twice the document.
     */
    for (i = 0; i < ctxt->txtNr; i++) {
	if (xmlStrEqual(URL, ctxt->txturlTab[i])) {
	    node = xmlCopyNode(ctxt->txtTab[i], 1);
	    goto loaded;
	}
    }
    /*
     * Try to get the encoding if available
     */
    if ((ctxt->incTab[nr] != NULL) && (ctxt->incTab[nr]->ref != NULL)) {
	encoding = xmlGetProp(ctxt->incTab[nr]->ref, XINCLUDE_PARSE_ENCODING);
    }
    if (encoding != NULL) {
	/*
	 * TODO: we should not have to remap to the xmlCharEncoding
	 *       predefined set, a better interface than
	 *       xmlParserInputBufferCreateFilename should allow any
	 *       encoding supported by iconv
	 */
        enc = xmlParseCharEncoding((const char *) encoding);
	if (enc == XML_CHAR_ENCODING_ERROR) {
	    xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
	                   XML_XINCLUDE_UNKNOWN_ENCODING,
			   "encoding %s not supported\n", encoding);
	    xmlFree(encoding);
	    xmlFree(URL);
	    return(-1);
	}
	xmlFree(encoding);
    }

    /*
     * Load it.
     */
    buf = xmlParserInputBufferCreateFilename((const char *)URL, enc);
    if (buf == NULL) {
	xmlFree(URL);
	return(-1);
    }
    node = xmlNewText(NULL);

    /*
     * Scan all chars from the resource and add the to the node
     */
    while (xmlParserInputBufferRead(buf, 128) > 0) {
	int len;
	const xmlChar *content;

	content = xmlBufferContent(buf->buffer);
	len = xmlBufferLength(buf->buffer);
	for (i = 0;i < len;) {
	    int cur;
	    int l;

	    cur = xmlStringCurrentChar(NULL, &content[i], &l);
	    if (!IS_CHAR(cur)) {
		xmlXIncludeErr(ctxt, ctxt->incTab[nr]->ref,
		               XML_XINCLUDE_INVALID_CHAR,
			       "%s contains invalid char\n", URL);
	    } else {
		xmlNodeAddContentLen(node, &content[i], l);
	    }
	    i += l;
	}
	xmlBufferShrink(buf->buffer, len);
    }
    xmlFreeParserInputBuffer(buf);
    xmlXIncludeAddTxt(ctxt, node, URL);

loaded:
    /*
     * Add the element as the replacement copy.
     */
    ctxt->incTab[nr]->inc = node;
    xmlFree(URL);
    return(0);
}

/**
 * xmlXIncludeLoadFallback:
 * @ctxt:  the XInclude context
 * @fallback:  the fallback node
 * @nr:  the xinclude node number
 * 
 * Load the content of the fallback node, and store the result
 * in the XInclude context
 *
 * Returns 0 in case of success, -1 in case of failure
 */
static int
xmlXIncludeLoadFallback(xmlXIncludeCtxtPtr ctxt, xmlNodePtr fallback, int nr) {
    xmlXIncludeCtxtPtr newctxt;
    int ret = 0;
    
    if ((fallback == NULL) || (ctxt == NULL))
	return(-1);
    if (fallback->children != NULL) {
	/*
	 * It's possible that the fallback also has 'includes'
	 * (Bug 129969), so we re-process the fallback just in case
	 */
	newctxt = xmlXIncludeNewContext(ctxt->doc);
	if (newctxt == NULL)
	    return (-1);
	newctxt->base = xmlStrdup(ctxt->base);	/* Inherit the base from the existing context */
	xmlXIncludeSetFlags(newctxt, ctxt->parseFlags);
	ret = xmlXIncludeDoProcess(newctxt, ctxt->doc, fallback->children);
	if (ctxt->nbErrors > 0)
	    ret = -1;
	else if (ret > 0)
	    ret = 0;	/* xmlXIncludeDoProcess can return +ve number */
	xmlXIncludeFreeContext(newctxt);

	ctxt->incTab[nr]->inc = xmlDocCopyNodeList(ctxt->doc,
	                                           fallback->children);
    } else {
        ctxt->incTab[nr]->inc = NULL;
	ctxt->incTab[nr]->emptyFb = 1;	/* flag empty callback */
    }
    return(ret);
}

/************************************************************************