Add class to encapsulate a CF Mach Message Source and handle it's liftime.

This class handles adding a listener on Mach port to the current CFRunloop and
calling a delegate when a message is received on that port.

Review URL: http://codereview.chromium.org/11331

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@5936 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 59 insertions, 0 deletions

diff --git a/chrome/common/mach_message_source_mac.h b/chrome/common/mach_message_source_mac.h
new file mode 100644
index 0000000..f57539d
--- /dev/null
+++ b/chrome/common/mach_message_source_mac.h
@@ -0,0 +1,59 @@
+// Copyright (c) 2008 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_COMMON_MACH_MESSAGE_SOURCE_MAC_H_
+#define CHROME_COMMON_MACH_MESSAGE_SOURCE_MAC_H_
+
+#include <CoreServices/CoreServices.h>
+
+#include "base/scoped_cftyperef.h"
+
+// Handles registering and cleaning up after a CFRunloopSource for a Mach port.
+// Messages received on the port are piped through to a delegate.
+//
+// Example:
+//  class MyListener : public MachMessageSource::MachPortListener {
+//   public:
+//    void OnMachMessageReceived(void* mach_msg, size_t size) {
+//      printf("received message on Mach port\n");
+//    }
+//  };
+//
+//  mach_port_t a_port = ...;
+//  MyListener listener;
+//  bool success = false;
+//  MachMessageSource message_source(port, listener, &success);
+//
+//  if (!success) {
+//    exit(1);  // Couldn't register mach runloop source.
+//  }
+//
+//  CFRunLoopRun();  // Process messages on runloop...
+class MachMessageSource {
+ public:
+  // Classes that want to listen on a Mach port can implement
+  // OnMachMessageReceived, |mach_msg| is a pointer to the raw message data and
+  // |size| is the buffer size;
+  class MachPortListener {
+   public:
+    virtual void OnMachMessageReceived(void* mach_msg, size_t size) = 0;
+  };
+
+  // |listener| is a week reference passed to CF, it needs to remain in
+  // existence till this object is destroeyd.
+  MachMessageSource(mach_port_t port,
+                    MachPortListener* listener,
+                    bool* success);
+  ~MachMessageSource();
+
+ private:
+  // Called by CF when a new message arrives on the Mach port.
+  static void OnReceiveMachMessage(CFMachPortRef port, void* msg, CFIndex size,
+                                   void* closure);
+
+  scoped_cftyperef<CFRunLoopSourceRef> machport_runloop_ref_;
+  DISALLOW_COPY_AND_ASSIGN(MachMessageSource);
+};
+
+#endif // CHROME_COMMON_MACH_MESSAGE_SOURCE_MAC_H_