Function xmlXPathCtxtCompile

ThirdParty/libxml2/vtklibxml2/xpath.c:13031–13103

* xmlXPathCtxtCompile: * @ctxt: an XPath context * @str: the XPath expression * * Compile an XPath expression * * Returns the xmlXPathCompExprPtr resulting from the compilation or NULL. * the caller has to free the object. */

 *         the caller has to free the object.
 */
xmlXPathCompExprPtr
xmlXPathCtxtCompile(xmlXPathContextPtr ctxt, const xmlChar *str) {
    xmlXPathParserContextPtr pctxt;
    xmlXPathContextPtr tmpctxt = NULL;
    xmlXPathCompExprPtr comp;
    int oldDepth = 0;

#ifdef XPATH_STREAMING
    comp = xmlXPathTryStreamCompile(ctxt, str);
    if (comp != NULL)
        return(comp);
#endif

    xmlInitParser();

    /*
     * We need an xmlXPathContext for the depth check.
     */
    if (ctxt == NULL) {
        tmpctxt = xmlXPathNewContext(NULL);
        if (tmpctxt == NULL)
            return(NULL);
        ctxt = tmpctxt;
    }

    pctxt = xmlXPathNewParserContext(str, ctxt);
    if (pctxt == NULL) {
        if (tmpctxt != NULL)
            xmlXPathFreeContext(tmpctxt);
        return NULL;
    }

    oldDepth = ctxt->depth;
    xmlXPathCompileExpr(pctxt, 1);
    ctxt->depth = oldDepth;

    if( pctxt->error != XPATH_EXPRESSION_OK )
    {
        xmlXPathFreeParserContext(pctxt);
        if (tmpctxt != NULL)
            xmlXPathFreeContext(tmpctxt);
        return(NULL);
    }

    if (*pctxt->cur != 0) {
	/*
	 * aleksey: in some cases this line prints *second* error message
	 * (see bug #78858) and probably this should be fixed.
	 * However, we are not sure that all error messages are printed
	 * out in other places. It's not critical so we leave it as-is for now
	 */
	xmlXPatherror(pctxt, __FILE__, __LINE__, XPATH_EXPR_ERROR);
	comp = NULL;
    } else {
	comp = pctxt->comp;
	if ((comp->nbStep > 1) && (comp->last >= 0)) {
            if (ctxt != NULL)
                oldDepth = ctxt->depth;