| // Copyright (c) 2006-2009 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 BASE_FILE_DESCRIPTOR_POSIX_H_ |
| #define BASE_FILE_DESCRIPTOR_POSIX_H_ |
| |
| #include "base/files/file.h" |
| #include "base/files/scoped_file.h" |
| |
| namespace base { |
| |
| constexpr int kInvalidFd = -1; |
| |
| // ----------------------------------------------------------------------------- |
| // We introduct a special structure for file descriptors in order that we are |
| // able to use template specialisation to special-case their handling. |
| // |
| // IMPORTANT: This is primarily intended for use when sending file descriptors |
| // over IPC. Even if |auto_close| is true, base::FileDescriptor does NOT close() |
| // |fd| when going out of scope. Instead, a consumer of a base::FileDescriptor |
| // must invoke close() on |fd| if |auto_close| is true. |
| // |
| // In the case of IPC, the the IPC subsystem knows to close() |fd| after sending |
| // a message that contains a base::FileDescriptor if auto_close == true. On the |
| // other end, the receiver must make sure to close() |fd| after it has finished |
| // processing the IPC message. See the IPC::ParamTraits<> specialization in |
| // ipc/ipc_message_utils.h for all the details. |
| // ----------------------------------------------------------------------------- |
| struct FileDescriptor { |
| FileDescriptor() : fd(kInvalidFd), auto_close(false) {} |
| |
| FileDescriptor(int ifd, bool iauto_close) : fd(ifd), auto_close(iauto_close) { |
| } |
| |
| FileDescriptor(File file) : fd(file.TakePlatformFile()), auto_close(true) {} |
| explicit FileDescriptor(ScopedFD fd) : fd(fd.release()), auto_close(true) {} |
| |
| bool operator==(const FileDescriptor& other) const { |
| return (fd == other.fd && auto_close == other.auto_close); |
| } |
| |
| bool operator!=(const FileDescriptor& other) const { |
| return !operator==(other); |
| } |
| |
| // A comparison operator so that we can use these as keys in a std::map. |
| bool operator<(const FileDescriptor& other) const { |
| return other.fd < fd; |
| } |
| |
| int fd; |
| // If true, this file descriptor should be closed after it has been used. For |
| // example an IPC system might interpret this flag as indicating that the |
| // file descriptor it has been given should be closed after use. |
| bool auto_close; |
| }; |
| |
| } // namespace base |
| |
| #endif // BASE_FILE_DESCRIPTOR_POSIX_H_ |