Separates ipc code from common (http://crbug.com/16829)

chrome/common/ipc_sync_message.h

-// Copyright (c) 2006-2008 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_IPC_SYNC_MESSAGE_H__
-#define CHROME_COMMON_IPC_SYNC_MESSAGE_H__
-
-#if defined(OS_WIN)
-#include <windows.h>
-#endif
-#include <string>
-#include "base/basictypes.h"
-#include "chrome/common/ipc_message.h"
-
-namespace base {
-class WaitableEvent;
-}
-
-namespace IPC {
-
-class MessageReplyDeserializer;
-
-class SyncMessage : public Message {
- public:
-  SyncMessage(int32 routing_id, uint16 type, PriorityValue priority,
-              MessageReplyDeserializer* deserializer);
-
-  // Call this to get a deserializer for the output parameters.
-  // Note that this can only be called once, and the caller is responsible
-  // for deleting the deserializer when they're done.
-  MessageReplyDeserializer* GetReplyDeserializer();
-
-  // If this message can cause the receiver to block while waiting for user
-  // input (i.e. by calling MessageBox), then the caller needs to pump window
-  // messages and dispatch asynchronous messages while waiting for the reply.
-  // If this event is passed in, then window messages will start being pumped
-  // when it's set.  Note that this behavior will continue even if the event is
-  // later reset.  The event must be valid until after the Send call returns.
-  void set_pump_messages_event(base::WaitableEvent* event) {
-    pump_messages_event_ = event;
-    if (event) {
-      header()->flags |= PUMPING_MSGS_BIT;
-    } else {
-      header()->flags &= ~PUMPING_MSGS_BIT;
-    }
-  }
-
-  // Call this if you always want to pump messages.  You can call this method
-  // or set_pump_messages_event but not both.
-  void EnableMessagePumping();
-
-  base::WaitableEvent* pump_messages_event() const {
-    return pump_messages_event_;
-  }
-
-  // Returns true if the message is a reply to the given request id.
-  static bool IsMessageReplyTo(const Message& msg, int request_id);
-
-  // Given a reply message, returns an iterator to the beginning of the data
-  // (i.e. skips over the synchronous specific data).
-  static void* GetDataIterator(const Message* msg);
-
-  // Given a synchronous message (or its reply), returns its id.
-  static int GetMessageId(const Message& msg);
-
-  // Generates a reply message to the given message.
-  static Message* GenerateReply(const Message* msg);
-
- private:
-  struct SyncHeader {
-    // unique ID (unique per sender)
-    int message_id;
-  };
-
-  static bool ReadSyncHeader(const Message& msg, SyncHeader* header);
-  static bool WriteSyncHeader(Message* msg, const SyncHeader& header);
-
-  MessageReplyDeserializer* deserializer_;
-  base::WaitableEvent* pump_messages_event_;
-
-  static uint32 next_id_;  // for generation of unique ids
-};
-
-// Used to deserialize parameters from a reply to a synchronous message
-class MessageReplyDeserializer {
- public:
-  bool SerializeOutputParameters(const Message& msg);
- private:
-  // Derived classes need to implement this, using the given iterator (which
-  // is skipped past the header for synchronous messages).
-  virtual bool SerializeOutputParameters(const Message& msg, void* iter) = 0;
-};
-
-}  // namespace IPC
-
-#endif  // CHROME_COMMON_IPC_SYNC_MESSAGE_H__