mojo/shell/external_application_listener.h

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef MOJO_SHELL_EXTERNAL_APPLICATION_LISTENER_H_
   6 #define MOJO_SHELL_EXTERNAL_APPLICATION_LISTENER_H_
   7
   8 #include "base/callback.h"
   9 #include "base/files/file_path.h"
  10 #include "base/memory/ref_counted.h"
  11 #include "base/memory/scoped_ptr.h"
  12 #include "base/sequenced_task_runner.h"
  13 #include "mojo/public/cpp/system/message_pipe.h"
  14 #include "net/socket/socket_descriptor.h"
  15 #include "url/gurl.h"
  16
  17 namespace mojo {
  18 namespace shell {
  19
  20 // In order to support Mojo apps whose lifetime is managed by
  21 // something other than mojo_shell, mojo_shell needs to support a
  22 // mechanism by which such an application can discover a running shell
  23 // instance, connect to it, and ask to be "registered" at a given
  24 // URL. Registration implies that the app can be connected to at that
  25 // URL from then on out, and that the app has received a usable ShellPtr.
  26 //
  27 // External applications can connect to the shell using the
  28 // ExternalApplicationRegistrarConnection class.
  29 class ExternalApplicationListener {
  30  public:
  31   // When run, a RegisterCallback should note that an app has asked to be
  32   // registered at app_url and Bind the provided pipe handle to a ShellImpl.
  33   typedef base::Callback<void(const GURL& app_url,
  34                               ScopedMessagePipeHandle shell)> RegisterCallback;
  35   typedef base::Callback<void(int rv)> ErrorCallback;
  36
  37   virtual ~ExternalApplicationListener() {}
  38
  39   // Implementations of this class may use two threads, an IO thread for
  40   // listening and accepting incoming sockets, and a "main" thread
  41   // where all Mojo traffic is processed and provided callbacks are run.
  42   static scoped_ptr<ExternalApplicationListener> Create(
  43       const scoped_refptr<base::SequencedTaskRunner>& shell_runner,
  44       const scoped_refptr<base::SequencedTaskRunner>& io_runner);
  45
  46   static base::FilePath ConstructDefaultSocketPath();
  47
  48   // Begin listening (on io_runner) to a socket at listen_socket_path.
  49   // Incoming registration requests will be forwarded to register_callback.
  50   // Errors are ignored.
  51   virtual void ListenInBackground(
  52       const base::FilePath& listen_socket_path,
  53       const RegisterCallback& register_callback) = 0;
  54
  55   // Begin listening (on io_runner) to a socket at listen_socket_path.
  56   // Incoming registration requests will be forwarded to register_callback.
  57   // Errors are reported via error_callback.
  58   virtual void ListenInBackgroundWithErrorCallback(
  59       const base::FilePath& listen_socket_path,
  60       const RegisterCallback& register_callback,
  61       const ErrorCallback& error_callback) = 0;
  62
  63   // Block the current thread until listening has started on io_runner.
  64   // If listening has already started, returns immediately.
  65   virtual void WaitForListening() = 0;
  66 };
  67
  68 }  // namespace shell
  69 }  // namespace mojo
  70
  71 #endif  // MOJO_SHELL_EXTERNAL_APPLICATION_LISTENER_H_