Method ResetFileDescriptor

src/brpc/socket.cpp:568–612

}

int Socket::ResetFileDescriptor(int fd) {
    // Reset message sizes when fd is changed.
    _last_msg_size = 0;
    _avg_msg_size = 0;
    // MUST store `_fd' before adding itself into epoll device to avoid
    // race conditions with the callback function inside epoll
    _fd.store(fd, butil::memory_order_release);
    _reset_fd_real_us = butil::cpuwide_time_us();
    if (!ValidFileDescriptor(fd)) {
        return 0;
    }
    if (_remote_side == butil::EndPoint()) {
        // OK to fail, non-socket fd does not support this.
        butil::get_remote_side(fd, &_remote_side);
    }
    // OK to fail, non-socket fd does not support this.
    butil::get_local_side(fd, &_local_side);

    // FIXME : close-on-exec should be set by new syscalls or worse: set right
    // after fd-creation syscall. Setting at here has higher probabilities of
    // race condition.
    butil::make_close_on_exec(fd);

    // Make the fd non-blocking.
    if (butil::make_non_blocking(fd) != 0) {
        PLOG(ERROR) << "Fail to set fd=" << fd << " to non-blocking";
        _fd.store(-1, butil::memory_order_release);
        return -1;
    }
    // turn off nagling.
    // OK to fail, namely unix domain socket does not support this.
    butil::make_no_delay(fd);

    SetSocketOptions(fd);

    if (_transport->HasOnEdgeTrigger()) {
        if (_io_event.AddConsumer(fd) != 0) {
            PLOG(ERROR) << "Fail to add SocketId=" << id() 
                        << " into EventDispatcher";
            _fd.store(-1, butil::memory_order_release);
            return -1;
        }
    }
    return 0;
}

void Socket::SetSocketOptions(int fd) {
    if (_tos > 0 &&