| // Copyright 2019 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. |
| |
| #include "platform/impl/socket_handle_waiter_posix.h" |
| |
| #include <time.h> |
| |
| #include <algorithm> |
| #include <vector> |
| |
| #include "platform/base/error.h" |
| #include "platform/impl/socket_handle_posix.h" |
| #include "platform/impl/timeval_posix.h" |
| #include "platform/impl/udp_socket_posix.h" |
| #include "util/osp_logging.h" |
| |
| namespace openscreen { |
| |
| SocketHandleWaiterPosix::SocketHandleWaiterPosix( |
| ClockNowFunctionPtr now_function) |
| : SocketHandleWaiter(now_function) {} |
| |
| SocketHandleWaiterPosix::~SocketHandleWaiterPosix() = default; |
| |
| ErrorOr<std::vector<SocketHandleWaiterPosix::ReadyHandle>> |
| SocketHandleWaiterPosix::AwaitSocketsReadable( |
| const std::vector<SocketHandleRef>& socket_handles, |
| const Clock::duration& timeout) { |
| int max_fd = -1; |
| fd_set read_handles; |
| fd_set write_handles; |
| |
| FD_ZERO(&read_handles); |
| FD_ZERO(&write_handles); |
| for (const SocketHandle& handle : socket_handles) { |
| FD_SET(handle.fd, &read_handles); |
| FD_SET(handle.fd, &write_handles); |
| max_fd = std::max(max_fd, handle.fd); |
| } |
| if (max_fd < 0) { |
| return Error::Code::kIOFailure; |
| } |
| |
| struct timeval tv = ToTimeval(timeout); |
| // This value is set to 'max_fd + 1' by convention. Also, select() is |
| // level-triggered so incomplete reads/writes by the caller are fine and will |
| // be picked up again on the next select() call. For more information, see: |
| // http://man7.org/linux/man-pages/man2/select.2.html |
| int max_fd_to_watch = max_fd + 1; |
| const int rv = |
| select(max_fd_to_watch, &read_handles, &write_handles, nullptr, &tv); |
| if (rv == -1) { |
| // This is the case when an error condition is hit within the select(...) |
| // command. |
| return Error::Code::kIOFailure; |
| } else if (rv == 0) { |
| // This occurs when no sockets have a pending read. |
| return Error::Code::kAgain; |
| } |
| |
| std::vector<ReadyHandle> changed_handles; |
| for (const SocketHandleRef& handle : socket_handles) { |
| uint32_t flags = 0; |
| if (FD_ISSET(handle.get().fd, &read_handles)) { |
| flags |= Flags::kReadable; |
| } |
| if (FD_ISSET(handle.get().fd, &write_handles)) { |
| flags |= Flags::kWriteable; |
| } |
| if (flags) { |
| changed_handles.push_back({handle, flags}); |
| } |
| } |
| |
| return changed_handles; |
| } |
| |
| void SocketHandleWaiterPosix::RunUntilStopped() { |
| const bool was_running = is_running_.exchange(true); |
| OSP_CHECK(!was_running); |
| |
| constexpr Clock::duration kHandleReadyTimeout = std::chrono::milliseconds(50); |
| while (is_running_) { |
| ProcessHandles(kHandleReadyTimeout); |
| } |
| } |
| |
| void SocketHandleWaiterPosix::RequestStopSoon() { |
| is_running_.store(false); |
| } |
| |
| } // namespace openscreen |