Take out common functionality from PluginProcessHost and move it to ChildProcessHost.

Review URL: http://codereview.chromium.org/21443

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@9935 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 108 insertions, 0 deletions

diff --git a/chrome/common/child_process_host.h b/chrome/common/child_process_host.h
new file mode 100644
index 0000000..01db515
--- /dev/null
+++ b/chrome/common/child_process_host.h
@@ -0,0 +1,108 @@
+// Copyright (c) 2009 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_CHILD_PROCESS_HOST_H_
+#define CHROME_COMMON_CHILD_PROCESS_HOST_H_
+
+#include <list>
+
+#include "base/basictypes.h"
+#include "base/object_watcher.h"
+#include "chrome/common/child_process_info.h"
+#include "chrome/common/ipc_channel.h"
+
+class MessageLoop;
+class NotificationType;
+
+// Plugins/workers and other child processes that live on the IO thread should
+// derive from this class.
+class ChildProcessHost : public ChildProcessInfo,
+                         public base::ObjectWatcher::Delegate,
+                         public IPC::Channel::Listener,
+                         public IPC::Message::Sender {
+ public:
+  virtual ~ChildProcessHost();
+
+  // IPC::Message::Sender implementation:
+  virtual bool Send(IPC::Message* msg);
+
+  // The Iterator class allows iteration through either all child processes, or
+  // ones of a specific type, depending on which constructor is used.  Note that
+  // this should be done from the IO thread and that the iterator should not be
+  // kept around as it may be invalidated on subsequent event processing in the
+  // event loop.
+  class Iterator {
+   public:
+    Iterator();
+    Iterator(ProcessType type);
+    ChildProcessInfo* operator->() { return *iterator_; }
+    ChildProcessInfo* operator*() { return *iterator_; }
+    ChildProcessInfo* operator++();
+    bool Done();
+
+   private:
+    bool all_;
+    ProcessType type_;
+    std::list<ChildProcessInfo*>::iterator iterator_;
+  };
+
+ protected:
+  ChildProcessHost(ProcessType type, MessageLoop* main_message_loop);
+
+  // Creates the IPC channel.  Returns true iff it succeeded.
+  bool CreateChannel();
+
+  // Once the subclass gets a handle to the process, it needs to tell
+  // ChildProcessHost using this function.
+  void SetHandle(base::ProcessHandle handle);
+
+  // Notifies us that an instance has been created on this child process.
+  void InstanceCreated();
+
+  // IPC::Channel::Listener implementation:
+  virtual void OnMessageReceived(const IPC::Message& msg) { }
+  virtual void OnChannelConnected(int32 peer_pid) { }
+  virtual void OnChannelError() { }
+
+  bool opening_channel() { return opening_channel_; }
+  const std::wstring& channel_id() { return channel_id_; }
+
+ private:
+  // Sends the given notification to the notification service on the UI thread.
+  void Notify(NotificationType type);
+
+  // ObjectWatcher::Delegate implementation:
+  virtual void OnObjectSignaled(HANDLE object);
+
+  // By using an internal class as the IPC::Channel::Listener, we can intercept
+  // OnMessageReceived/OnChannelConnected and do our own processing before
+  // calling the subclass' implementation.
+  class ListenerHook : public IPC::Channel::Listener {
+   public:
+    ListenerHook(ChildProcessHost* host);
+    virtual void OnMessageReceived(const IPC::Message& msg);
+    virtual void OnChannelConnected(int32 peer_pid);
+    virtual void OnChannelError();
+   private:
+    ChildProcessHost* host_;
+  };
+
+  ListenerHook listener_;
+
+  MessageLoop* main_message_loop_;
+
+  // True while we're waiting the channel to be opened.
+  bool opening_channel_;
+
+  // The IPC::Channel.
+  scoped_ptr<IPC::Channel> channel_;
+
+  // IPC Channel's id.
+  std::wstring channel_id_;
+
+  // Used to watch the child process handle.
+  base::ObjectWatcher watcher_;
+};
+
+#endif  // CHROME_COMMON_CHILD_PROCESS_HOST_H_