Merge pull request #89 from ixti/master

Fix possible memleak with `exit` event handlers

lib/appenders/file.js

@@ -5,6 +5,9 @@ var layouts = require('../layouts')
 , os = require('os')
 , eol = os.EOL || '\n';
 
+var openFiles = [];
+var listenerAtttached = false;
+
 /**
  * File Appender writing the logs to a text file. Supports rolling of logs by size.
  *
@@ -42,10 +45,18 @@ function fileAppender (file, layout, logSize, numBackups) {
 
     var logFile = openTheStream(file, logSize, numBackups);
 
+    // push file to the stack of open handlers
+    openFiles.push(logFile);
+
     //close the file on process exit.
-    process.on('exit', function() {
-        logFile.end();
-    });
+    if (!listenerAtttached) {
+        listenerAtttached = true;
+        process.on('exit', function() {
+            openFiles.forEach(function (file) {
+                file.end();
+            });
+        });
+    }
 
     return function(loggingEvent) {
         logFile.write(layout(loggingEvent) + eol, "utf8");

test/fileAppender-test.js

@@ -15,6 +15,24 @@ function remove(filename) {
 }
 
 vows.describe('log4js fileAppender').addBatch({
+    'adding multiple fileAppenders': {
+      topic: function () {
+          var listenersCount = process.listeners('exit').length
+            , logger = log4js.getLogger('default-settings')
+            , count = 5, logfile;
+
+          while (count--) {
+              logfile = path.join(__dirname, '/fa-default-test' + count + '.log');
+              log4js.addAppender(require('../lib/appenders/file').appender(logfile), 'default-settings');
+          }
+
+          return listenersCount;
+      },
+
+      'does not adds more than one `exit` listeners': function (initialCount) {
+          assert.ok(process.listeners('exit').length <= initialCount + 1);
+      }
+    },
 
     'with default fileAppender settings': {
         topic: function() {