From f3681b9aa23445759cfce753be59b26a6271c962 Mon Sep 17 00:00:00 2001
From: Andrey Sidorov <sidorares@yandex.ru>
Date: Mon, 16 Jul 2012 19:48:03 +1000
Subject: [PATCH] ping() and close() for connection

---
 lib/x11/xcore.js         | 23 +++++++++++++++++++++++
 test/connection-utils.js | 34 ++++++++++++++++++++++++++++++++++
 2 files changed, 57 insertions(+)
 create mode 100644 test/connection-utils.js

diff --git a/lib/x11/xcore.js b/lib/x11/xcore.js
index 6fcafcf..28cd9a6 100644
--- a/lib/x11/xcore.js
+++ b/lib/x11/xcore.js
@@ -74,6 +74,7 @@ function XClient(stream, displayNum, screenNum)
     this.importRequestsFromTemplates(this, coreRequests);
     
     this.startHandshake();
+    this._closing = false;
 }
 util.inherits(XClient, EventEmitter);
 
@@ -83,6 +84,25 @@ XClient.prototype.terminate = function()
     this.stream.end();
 }
 
+// GetAtomName used as cheapest non-modifying request with reply
+// 3 - id for shortest standard atom, "ARC"
+XClient.prototype.ping = function(cb) {
+   this.GetAtomName(3, function(err, str) {
+      if (err) return cb(err);
+      return cb();
+   });
+}
+
+XClient.prototype.close = function(cb) {
+    var cli = this;
+    cli.ping(function(err) {
+      if (err) return cb(err);
+      cli.terminate();
+      if (cb) cb();
+    });
+    cli._closing = true;
+}
+
 XClient.prototype.importRequestsFromTemplates = function(target, reqs)
 {
     var client = this;
@@ -93,6 +113,9 @@ XClient.prototype.importRequestsFromTemplates = function(target, reqs)
             
             var reqFunc = function req_proxy() {
             
+            if (client._closing)
+               throw new Error('client is in closing state');
+   
             // simple overflow handling (this means that currently there is no way to have more than 65535 requests in the queue
             // TODO: edge cases testing 
             if (client.seq_num == 65535)
diff --git a/test/connection-utils.js b/test/connection-utils.js
new file mode 100644
index 0000000..41863b5
--- /dev/null
+++ b/test/connection-utils.js
@@ -0,0 +1,34 @@
+var x11 = require('../lib/x11');
+var should = require('should');
+var assert = require('assert');
+
+describe('Client', function() {
+
+  var display;
+  beforeEach(function(done) {
+      var client = x11.createClient(function(dpy) {
+      display=dpy;
+      done();
+      client.removeListener('error', done);
+    });
+    client.on('error', done);
+  });
+
+  it('should respond to ping()', function(done) {
+    display.client.ping(done);
+  });
+
+  it('should allow to enqueue requests and gracefully execute them before close()', function(done) {
+    var count = 0;
+    var pong = function(err) { if (err) return done(err); count++; }
+    display.client.ping(pong);    
+      display.client.ping(pong);
+      display.client.ping(pong);
+      display.client.ping(pong);
+      display.client.close(function(err) {
+        if (err) return done(err);
+        assert.equal(count,4);
+        done();
+      });
+   })
+});