$data = null;
$have_data = false;
$closure = false;
+ $badhookmsg = false;
/* $hook can be: a function, an object, an array of $function and $data,
* an array of just a function, an array of object and method, or an
// Run autoloader (workaround for call_user_func_array bug)
is_callable( $callback );
- /* Call the hook. */
+ /* Call the hook. The documentation of call_user_func_array clearly
+ * states that FALSE is returned on failure. However this is not
+ * case always. In some version of PHP if the function signature
+ * does not match the call signature, PHP will issue an warning:
+ * Param y in x expected to be a reference, value given.
+ *
+ * In that case the call will also return null. The following code
+ * catches that warning and provides better error message. The
+ * function documentation also says that:
+ * In other words, it does not depend on the function signature
+ * whether the parameter is passed by a value or by a reference.
+ * There is also PHP bug http://bugs.php.net/bug.php?id=47554 which
+ * is unsurprisingly marked as bogus. In short handling of failures
+ * with call_user_func_array is a failure, the documentation for that
+ * function is wrong and misleading and PHP developers don't see any
+ * problem here.
+ */
+ $retval = null;
+ $handler = set_error_handler( 'hookErrorHandler' );
wfProfileIn( $func );
- $retval = call_user_func_array( $callback, $hook_args );
+ try {
+ $retval = call_user_func_array( $callback, $hook_args );
+ } catch ( MWHookException $e ) {
+ $badhookmsg = $e->getMessage();
+ }
wfProfileOut( $func );
+ // Need to check for null, because set_error_handler borks on it... sigh
+ if ( $handler !== null ) set_error_handler( $handler );
/* String return is an error; false return means stop processing. */
} else {
$prettyFunc = strval( $callback );
}
- throw new MWException( "Detected bug in an extension! " .
- "Hook $prettyFunc failed to return a value; " .
- "should return true to continue hook processing or false to abort." );
+ if ( $badhookmsg ) {
+ throw new MWException( "Detected bug in an extension! " .
+ "Hook $prettyFunc has invalid call signature; " . $badhookmsg );
+ } else {
+ throw new MWException( "Detected bug in an extension! " .
+ "Hook $prettyFunc failed to return a value; " .
+ "should return true to continue hook processing or false to abort." );
+ }
} else if ( !$retval ) {
return false;
}
return true;
}
+
+function hookErrorHandler( $errno, $errstr ) {
+ if ( strpos( $errstr, 'expected to be a reference, value given' ) !== false ) {
+ throw new MWHookException( $errstr );
+ }
+ return false;
+}
+
+class MWHookException extends MWException {}
\ No newline at end of file