1 // Copyright (c) 2012 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 IPC_IPC_CHANNEL_HANDLE_H_ 6 #define IPC_IPC_CHANNEL_HANDLE_H_ 7 8 #include <string> 9 10 #include "build/build_config.h" 11 #include "mojo/public/cpp/system/message_pipe.h" 12 13 #if defined(OS_POSIX) 14 #include "base/file_descriptor_posix.h" 15 #elif defined(OS_WIN) 16 #include <windows.h> 17 #endif // defined (OS_WIN) 18 19 // On Windows, any process can create an IPC channel and others can fetch 20 // it by name. We pass around the channel names over IPC. 21 // On Windows the initialization of ChannelHandle with an existing pipe 22 // handle is provided for convenience. 23 // NOTE: A ChannelHandle with a pipe handle Will NOT be marshalled over IPC. 24 25 // On POSIX, we instead pass around handles to channel endpoints via IPC. 26 // When it's time to IPC a new channel endpoint around, we send both the 27 // channel name as well as a base::FileDescriptor, which is itself a special 28 // type that knows how to copy a socket endpoint over IPC. 29 // 30 // In sum, this data structure can be used to pass channel information by name 31 // in both Windows and Posix. When passing a handle to a channel over IPC, 32 // use this data structure only for POSIX. 33 34 namespace IPC { 35 36 struct ChannelHandle { 37 // Note that serialization for this object is defined in the ParamTraits 38 // template specialization in ipc_message_utils.h. ChannelHandleChannelHandle39 ChannelHandle() {} 40 // The name that is passed in should be an absolute path for Posix. 41 // Otherwise there may be a problem in IPC communication between 42 // processes with different working directories. ChannelHandleChannelHandle43 ChannelHandle(const std::string& n) : name(n) {} ChannelHandleChannelHandle44 ChannelHandle(const char* n) : name(n) {} 45 #if defined(OS_WIN) ChannelHandleChannelHandle46 explicit ChannelHandle(HANDLE h) : pipe(h) {} 47 #elif defined(OS_POSIX) ChannelHandleChannelHandle48 ChannelHandle(const std::string& n, const base::FileDescriptor& s) 49 : name(n), socket(s) {} 50 #endif // defined(OS_POSIX) ChannelHandleChannelHandle51 ChannelHandle(mojo::MessagePipeHandle h) : mojo_handle(h) {} 52 53 std::string name; 54 #if defined(OS_POSIX) 55 base::FileDescriptor socket; 56 #elif defined(OS_WIN) 57 // A simple container to automatically initialize pipe handle 58 struct PipeHandle { PipeHandleChannelHandle::PipeHandle59 PipeHandle() : handle(NULL) {} PipeHandleChannelHandle::PipeHandle60 PipeHandle(HANDLE h) : handle(h) {} 61 HANDLE handle; 62 }; 63 PipeHandle pipe; 64 #endif // defined (OS_WIN) 65 mojo::MessagePipeHandle mojo_handle; 66 }; 67 68 } // namespace IPC 69 70 #endif // IPC_IPC_CHANNEL_HANDLE_H_ 71