From 08e3be88064e06d30a171d98aaae82f5928eec8d Mon Sep 17 00:00:00 2001
From: sam marshall <s.marshall@open.ac.uk>
Date: Tue, 20 Sep 2016 14:49:10 +0100
Subject: [PATCH] MDL-56038 Web services: json_last_error_msg not in PHP 5.4

---
 lib/ajax/service.php | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/lib/ajax/service.php b/lib/ajax/service.php
index 5437f1a4b5d..43ce3f70438 100644
--- a/lib/ajax/service.php
+++ b/lib/ajax/service.php
@@ -36,7 +36,12 @@ $rawjson = file_get_contents('php://input');
 
 $requests = json_decode($rawjson, true);
 if ($requests === null) {
-    $lasterror = json_last_error_msg();
+    if (function_exists('json_last_error_msg')) {
+        $lasterror = json_last_error_msg();
+    } else {
+        // Fall back to numeric error for older PHP version.
+        $lasterror = json_last_error();
+    }
     throw new coding_exception('Invalid json in request: ' . $lasterror);
 }
 $responses = array();