Function start_connect_attempt

libavformat/network.c:351–398

Returns < 0 on error, 0 on successfully started connection attempt, > 0 for a connection that succeeded already.

// Returns < 0 on error, 0 on successfully started connection attempt,
// > 0 for a connection that succeeded already.
static int start_connect_attempt(struct ConnectionAttempt *attempt,
                                 struct addrinfo **ptr, int timeout_ms,
                                 URLContext *h,
                                 int (*customize_fd)(void *, int, int), void *customize_ctx)
{
    struct addrinfo *ai = *ptr;
    int ret;

    *ptr = ai->ai_next;

    attempt->fd = ff_socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol, h);
    if (attempt->fd < 0)
        return ff_neterrno();
    attempt->deadline_us = av_gettime_relative() + timeout_ms * 1000;
    attempt->addr = ai;

    ff_socket_nonblock(attempt->fd, 1);

    if (customize_fd) {
        ret = customize_fd(customize_ctx, attempt->fd, ai->ai_family);
        if (ret) {
            closesocket(attempt->fd);
            attempt->fd = -1;
            return ret;
        }
    }

    while ((ret = connect(attempt->fd, ai->ai_addr, ai->ai_addrlen))) {
        ret = ff_neterrno();
        switch (ret) {
        case AVERROR(EINTR):
            if (ff_check_interrupt(&h->interrupt_callback)) {
                closesocket(attempt->fd);
                attempt->fd = -1;
                return AVERROR_EXIT;
            }
            continue;
        case AVERROR(EINPROGRESS):
        case AVERROR(EAGAIN):
            return 0;
        default:
            closesocket(attempt->fd);
            attempt->fd = -1;
            return ret;
        }
    }
    return 1;
}

// Try a new connection to another address after 200 ms, as suggested in
// RFC 8305 (or sooner if an earlier attempt fails).