Function initialize

libavformat/whip.c:449–499

* Initialize and check the options for the WebRTC muxer. */

 * Initialize and check the options for the WebRTC muxer.
 */
static av_cold int initialize(AVFormatContext *s)
{
    int ret, ideal_pkt_size = 532;
    WHIPContext *whip = s->priv_data;
    uint32_t seed;

    whip->whip_starttime = av_gettime_relative();

    ret = certificate_key_init(s);
    if (ret < 0) {
        av_log(whip, AV_LOG_ERROR, "Failed to init certificate and key\n");
        return ret;
    }

    /* Initialize the random number generator. */
    seed = av_get_random_seed();
    av_lfg_init(&whip->rnd, seed);

    /* 64 bit tie breaker for ICE-CONTROLLING (RFC 8445 16.1) */
    ret = av_random_bytes((uint8_t *)&whip->ice_tie_breaker, sizeof(whip->ice_tie_breaker));
    if (ret < 0) {
        av_log(whip, AV_LOG_ERROR, "Couldn't generate random bytes for ICE tie breaker\n");
        return ret;
    }

    whip->audio_first_seq = av_lfg_get(&whip->rnd) & 0x0fff;
    whip->video_first_seq = whip->audio_first_seq + 1;

    if (whip->pkt_size < ideal_pkt_size)
        av_log(whip, AV_LOG_WARNING, "pkt_size=%d(<%d) is too small, may cause packet loss\n",
               whip->pkt_size, ideal_pkt_size);

    whip->hist = av_calloc(whip->hist_sz, sizeof(*whip->hist));
    if (!whip->hist)
        return AVERROR(ENOMEM);

    whip->hist_pool = av_calloc(whip->hist_sz, whip->pkt_size - DTLS_SRTP_CHECKSUM_LEN);
    if (!whip->hist_pool)
        return AVERROR(ENOMEM);

    for (int i = 0; i < whip->hist_sz; i++)
        whip->hist[i].buf = whip->hist_pool + i * (whip->pkt_size - DTLS_SRTP_CHECKSUM_LEN);

    if (whip->state < WHIP_STATE_INIT)
        whip->state = WHIP_STATE_INIT;
    whip->whip_init_time = av_gettime_relative();
    av_log(whip, AV_LOG_VERBOSE, "Init state=%d, handshake_timeout=%dms, pkt_size=%d, seed=%d, elapsed=%.2fms\n",
        whip->state, whip->handshake_timeout, whip->pkt_size, seed, ELAPSED(whip->whip_starttime, av_gettime_relative()));

    return 0;
}

/**
 * When duplicating a stream, the demuxer has already set the extradata, profile, and