index.php: Hacky way of telling the php error handler to skip stack frames

This can be used to show more meaningful error messages in debug mode at
the bottom of the page. Prefix the error message with [skip:N] where
N is the number of stack frames to skip when printing the error message.
The php error log will still receive the complete stack trace.

1 files changed, 9 insertions, 0 deletions

diff --git a/index.php b/index.php
index d7018e17..4816ef42 100644
--- a/index.php
+++ b/index.php
@@ -104,6 +104,15 @@ spl_autoload_register(function ($class) {
 
 if (defined('CONFIG_DEBUG') && CONFIG_DEBUG) {
 	set_error_handler(function ($errno, $errstr, $errfile, $errline) {
+		if (preg_match('/^\[skip:\s*(\d+)\]\s*(.*)/is', $errstr, $out)) {
+			$errstr = $out[2];
+			$trace = debug_backtrace();
+			$idx = (int)$out[1] + 1;
+			if (count($trace) > $idx) {
+				$errfile = $trace[$idx]['file'];
+				$errline = $trace[$idx]['line'];
+			}
+		}
 		global $SLX_ERRORS;
 		$SLX_ERRORS[] = array(
 			'errno' => $errno,