ZP-682 "filelog" and "syslog" classes can not be found by autoloader

(because they are in camel case and not lowercase). Rewriting the
backend loaded by ZLog to the class name, as this is more end-user
friendly.
Throwing a FatalNotImplementedException causes a recursion that eats up
all available memory before it fails, as that exception tries to log
which then throws the exception again.

Released under the Affero GNU General Public License (AGPL) version 3.

src/lib/core/zlog.php

@@ -161,9 +161,12 @@ class ZLog {
     static private function getLogger() {
         if (!self::$logger) {
             global $specialLogUsers; // This variable comes from the configuration file (config.php)
-            $logger = LOGBACKEND;
+
+            $logger = LOGBACKEND_CLASS;
             if (!class_exists($logger)) {
-                throw new FatalNotImplementedException('The logging class `'.$logger.'` does not exist.');
+                $errmsg = 'The configured logging class `'.$logger.'` does not exist. Check your configuration.';
+                error_log($errmsg);
+                throw new \Exception($errmsg);
             }
 
             list($user) = Utils::SplitDomainUser(strtolower(Request::GetGETUser()));

src/lib/core/zpush.php

@@ -225,7 +225,7 @@ class ZPush {
         }
 
         if (LOGBACKEND == 'syslog') {
-
+            define('LOGBACKEND_CLASS', 'Syslog');
             if (!defined('LOG_SYSLOG_FACILITY')) {
                 define('LOG_SYSLOG_FACILITY', LOG_LOCAL0);
             }
@@ -251,7 +251,7 @@ class ZPush {
             }
         }
         elseif (LOGBACKEND == 'filelog') {
-
+            define('LOGBACKEND_CLASS', 'FileLog');
             if (!defined('LOGFILEDIR'))
                 throw new FatalMisconfigurationException("The LOGFILEDIR is not configured. Check if the config.php file is in place.");
 
@@ -271,6 +271,9 @@ class ZPush {
             Utils::FixFileOwner(LOGFILE);
             Utils::FixFileOwner(LOGERRORFILE);
         }
+        else {
+            define('LOGBACKEND_CLASS', LOGBACKEND);
+        }
 
         // set time zone
         // code contributed by Robert Scheck (rsc)