Function WriteAll

src/brpc/policy/rtmp_protocol.cpp:603–624

Write all data in *buf into fd. Returns 0 on success, -1 otherwise. Writing *all* is possible because we only call this fn during handshaking and connecting, the data in total is generally less than socket buffer.

// Writing *all* is possible because we only call this fn during handshaking
// and connecting, the data in total is generally less than socket buffer.
static int WriteAll(int fd, butil::IOBuf* buf) {
    while (!buf->empty()) {
        ssize_t nw = buf->cut_into_file_descriptor(fd);
        if (nw < 0) {
            if (errno == EINTR) {
                continue;
            }
            if (errno == EAGAIN) {
                // Almost impossible because we only call this fn during
                // RTMP handshaking/connecting, the total size that we may
                // write is less than buffer size of the fd. If the
                // impossible really happens, just spin until the fd becomes
                // writable.
                LOG_EVERY_SECOND(ERROR) << "Impossible: meet EAGAIN!";
                bthread_usleep(1000);
                continue;
            }
            return -1;
        }
    }
    return 0;
}

// Send C0 C1 to the socket.
// Used in rtmp.cpp