Function http_read_header

libavformat/http.c:1438–1494

}

static int http_read_header(URLContext *h)
{
    HTTPContext *s = h->priv_data;
    char line[MAX_URL_SIZE];
    int err = 0, http_err = 0;

    av_freep(&s->new_location);
    s->expires = 0;
    s->chunksize = UINT64_MAX;
    s->filesize_from_content_range = UINT64_MAX;

    for (;;) {
        int parsed_http_code = 0;

        if ((err = http_get_line(s, line, sizeof(line))) < 0) {
            av_log(h, AV_LOG_ERROR, "Error reading HTTP response: %s\n",
                   av_err2str(err));
            return err;
        }

        av_log(h, AV_LOG_TRACE, "header='%s'\n", line);

        err = process_line(h, line, s->line_count, &parsed_http_code);
        if (err < 0) {
            if (parsed_http_code) {
                http_err = err;
            } else {
                /* Prefer to return HTTP code error if we've already seen one. */
                if (http_err)
                    return http_err;
                else
                    return err;
            }
        }
        if (err == 0)
            break;
        s->line_count++;
    }
    if (http_err)
        return http_err;

    // filesize from Content-Range can always be used, even if using chunked Transfer-Encoding
    if (s->filesize_from_content_range != UINT64_MAX)
        s->filesize = s->filesize_from_content_range;

    if (s->seekable == -1 && s->is_mediagateway && s->filesize == 2000000000)
        h->is_streamed = 1; /* we can in fact _not_ seek */

    if (h->is_streamed)
        s->initial_requests = 0; /* unable to use partial requests */

    // add any new cookies into the existing cookie string
    cookie_string(s->cookie_dict, &s->cookies);
    av_dict_free(&s->cookie_dict);

    return err;
}