leave length as -1, no need to strdup()

ext/curl/interface.c

@@ -467,7 +467,6 @@ static size_t curl_read(char *data, size_t size, size_t nmemb, void *ctx)
 			zval  *zfd = NULL;
 			zval  *zlength = NULL;
 			zval  *retval_ptr;
-			int   length;
 			int   error;
 			zend_fcall_info fci;
 			TSRMLS_FETCH_FROM_CTX(ch->thread_ctx);
@@ -499,13 +498,10 @@ static size_t curl_read(char *data, size_t size, size_t nmemb, void *ctx)
 			error = zend_call_function(&fci, &t->fci_cache TSRMLS_CC);
 			if (error == FAILURE) {
 				php_error_docref(NULL TSRMLS_CC, E_WARNING, "Cannot call the CURLOPT_READFUNCTION"); 
-				length = -1;
 			} else {
-				if(Z_TYPE_P(retval_ptr) == IS_STRING) {
+				if (Z_TYPE_P(retval_ptr) == IS_STRING) {
 					memcpy(data, Z_STRVAL_P(retval_ptr), size * nmemb);
 					length = Z_STRLEN_P(retval_ptr);
-				} else {
-					data = strdup("");
 				}
 			}