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

ipc/ipc_channel_posix.h

+// 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 IPC_IPC_CHANNEL_POSIX_H_
+#define IPC_IPC_CHANNEL_POSIX_H_
+
+#include "ipc/ipc_channel.h"
+
+#include <sys/socket.h>  // for CMSG macros
+
+#include <queue>
+#include <string>
+#include <vector>
+
+#include "base/message_loop.h"
+#include "ipc/file_descriptor_set_posix.h"
+
+namespace IPC {
+
+// Store that channel name |name| is available via socket |socket|.
+// Used when the channel has been precreated by another process on
+// our behalf and they've just shipped us the socket.
+void AddChannelSocket(const std::string& name, int socket);
+
+// Remove the channel name mapping, and close the corresponding socket.
+void RemoveAndCloseChannelSocket(const std::string& name);
+
+// Construct a socket pair appropriate for IPC: UNIX domain, nonblocking.
+// Returns false on error.
+bool SocketPair(int* fd1, int* fd2);
+
+// An implementation of ChannelImpl for POSIX systems that works via
+// socketpairs.  See the .cc file for an overview of the implementation.
+class Channel::ChannelImpl : public MessageLoopForIO::Watcher {
+ public:
+  // Mirror methods of Channel, see ipc_channel.h for description.
+  ChannelImpl(const std::string& channel_id, Mode mode, Listener* listener);
+  ~ChannelImpl() { Close(); }
+  bool Connect();
+  void Close();
+  void set_listener(Listener* listener) { listener_ = listener; }
+  bool Send(Message* message);
+  int GetClientFileDescriptor() const;
+
+ private:
+  bool CreatePipe(const std::string& channel_id, Mode mode);
+
+  bool ProcessIncomingMessages();
+  bool ProcessOutgoingMessages();
+
+  // MessageLoopForIO::Watcher implementation.
+  virtual void OnFileCanReadWithoutBlocking(int fd);
+  virtual void OnFileCanWriteWithoutBlocking(int fd);
+
+  Mode mode_;
+
+  // After accepting one client connection on our server socket we want to
+  // stop listening.
+  MessageLoopForIO::FileDescriptorWatcher server_listen_connection_watcher_;
+  MessageLoopForIO::FileDescriptorWatcher read_watcher_;
+  MessageLoopForIO::FileDescriptorWatcher write_watcher_;
+
+  // Indicates whether we're currently blocked waiting for a write to complete.
+  bool is_blocked_on_write_;
+
+  // If sending a message blocks then we use this variable
+  // to keep track of where we are.
+  size_t message_send_bytes_written_;
+
+  // If the kTestingChannelID flag is specified, we use a FIFO instead of
+  // a socketpair().
+  bool uses_fifo_;
+
+  // File descriptor we're listening on for new connections in the FIFO case;
+  // unused otherwise.
+  int server_listen_pipe_;
+
+  // The pipe used for communication.
+  int pipe_;
+
+  // For a server, the client end of our socketpair() -- the other end of our
+  // pipe_ that is passed to the client.
+  int client_pipe_;
+
+  // The "name" of our pipe.  On Windows this is the global identifier for
+  // the pipe.  On POSIX it's used as a key in a local map of file descriptors.
+  std::string pipe_name_;
+
+  Listener* listener_;
+
+  // Messages to be sent are queued here.
+  std::queue<Message*> output_queue_;
+
+  // We read from the pipe into this buffer
+  char input_buf_[Channel::kReadBufferSize];
+
+  enum {
+    // We assume a worst case: kReadBufferSize bytes of messages, where each
+    // message has no payload and a full complement of descriptors.
+    MAX_READ_FDS = (Channel::kReadBufferSize / sizeof(IPC::Message::Header)) *
+                   FileDescriptorSet::MAX_DESCRIPTORS_PER_MESSAGE,
+  };
+
+  // This is a control message buffer large enough to hold kMaxReadFDs
+#if defined(OS_MACOSX)
+  // TODO(agl): OSX appears to have non-constant CMSG macros!
+  char input_cmsg_buf_[1024];
+#else
+  char input_cmsg_buf_[CMSG_SPACE(sizeof(int) * MAX_READ_FDS)];
+#endif
+
+  // Large messages that span multiple pipe buffers, get built-up using
+  // this buffer.
+  std::string input_overflow_buf_;
+  std::vector<int> input_overflow_fds_;
+
+  // In server-mode, we have to wait for the client to connect before we
+  // can begin reading.  We make use of the input_state_ when performing
+  // the connect operation in overlapped mode.
+  bool waiting_connect_;
+
+  // This flag is set when processing incoming messages.  It is used to
+  // avoid recursing through ProcessIncomingMessages, which could cause
+  // problems.  TODO(darin): make this unnecessary
+  bool processing_incoming_;
+
+  ScopedRunnableMethodFactory<ChannelImpl> factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(ChannelImpl);
+};
+
+}  // namespace IPC
+
+#endif  // IPC_IPC_CHANNEL_POSIX_H_