Function xmlXPathCompOpEvalToBoolean

ThirdParty/libxml2/vtklibxml2/xpath.c:12367–12448

* xmlXPathCompOpEvalToBoolean: * @ctxt: the XPath parser context * * Evaluates if the expression evaluates to true. * * Returns 1 if true, 0 if false and -1 on API or internal errors. */

 * Returns 1 if true, 0 if false and -1 on API or internal errors.
 */
static int
xmlXPathCompOpEvalToBoolean(xmlXPathParserContextPtr ctxt,
			    xmlXPathStepOpPtr op,
			    int isPredicate)
{
    xmlXPathObjectPtr resObj = NULL;

start:
    if (OP_LIMIT_EXCEEDED(ctxt, 1))
        return(0);
    /* comp = ctxt->comp; */
    switch (op->op) {
        case XPATH_OP_END:
            return (0);
	case XPATH_OP_VALUE:
	    resObj = (xmlXPathObjectPtr) op->value4;
	    if (isPredicate)
		return(xmlXPathEvaluatePredicateResult(ctxt, resObj));
	    return(xmlXPathCastToBoolean(resObj));
	case XPATH_OP_SORT:
	    /*
	    * We don't need sorting for boolean results. Skip this one.
	    */
            if (op->ch1 != -1) {
		op = &ctxt->comp->steps[op->ch1];
		goto start;
	    }
	    return(0);
	case XPATH_OP_COLLECT:
	    if (op->ch1 == -1)
		return(0);

            xmlXPathCompOpEval(ctxt, &ctxt->comp->steps[op->ch1]);
	    if (ctxt->error != XPATH_EXPRESSION_OK)
		return(-1);

            xmlXPathNodeCollectAndTest(ctxt, op, NULL, NULL, 1);
	    if (ctxt->error != XPATH_EXPRESSION_OK)
		return(-1);

	    resObj = valuePop(ctxt);
	    if (resObj == NULL)
		return(-1);
	    break;
	default:
	    /*
	    * Fallback to call xmlXPathCompOpEval().
	    */
	    xmlXPathCompOpEval(ctxt, op);
	    if (ctxt->error != XPATH_EXPRESSION_OK)
		return(-1);

	    resObj = valuePop(ctxt);
	    if (resObj == NULL)
		return(-1);
	    break;
    }