Function hls_window

libavformat/hlsenc.c:1516–1658

}

static int hls_window(AVFormatContext *s, int last, VariantStream *vs)
{
    HLSContext *hls = s->priv_data;
    HLSSegment *en;
    int target_duration = 0;
    int ret = 0;
    char temp_filename[MAX_URL_SIZE];
    char temp_vtt_filename[MAX_URL_SIZE];
    int64_t sequence = FFMAX(hls->start_sequence, vs->sequence - vs->nb_entries);
    const char *proto = avio_find_protocol_name(vs->m3u8_name);
    int is_file_proto = proto && !strcmp(proto, "file");
    int use_temp_file = is_file_proto && ((hls->flags & HLS_TEMP_FILE) || !(hls->pl_type == PLAYLIST_TYPE_VOD));
    static unsigned warned_non_file;
    char *key_uri = NULL;
    char *iv_string = NULL;
    AVDictionary *options = NULL;
    double prog_date_time = vs->initial_prog_date_time;
    double *prog_date_time_p = (hls->flags & HLS_PROGRAM_DATE_TIME) ? &prog_date_time : NULL;
    int byterange_mode = (hls->flags & HLS_SINGLE_FILE) || (hls->max_seg_size > 0);

    hls->version = 2;
    if (!(hls->flags & HLS_ROUND_DURATIONS)) {
        hls->version = 3;
    }

    if (byterange_mode) {
        hls->version = 4;
        sequence = 0;
    }

    if (hls->flags & HLS_I_FRAMES_ONLY) {
        hls->version = 4;
    }

    if (hls->flags & HLS_INDEPENDENT_SEGMENTS) {
        hls->version = 6;
    }

    if (hls->segment_type == SEGMENT_TYPE_FMP4) {
        hls->version = 7;
    }

    if (!is_file_proto && (hls->flags & HLS_TEMP_FILE) && !warned_non_file++)
        av_log(s, AV_LOG_ERROR, "Cannot use rename on non file protocol, this may lead to races and temporary partial files\n");

    set_http_options(s, &options, hls);
    snprintf(temp_filename, sizeof(temp_filename), use_temp_file ? "%s.tmp" : "%s", vs->m3u8_name);
    ret = hlsenc_io_open(s, byterange_mode ? &hls->m3u8_out : &vs->out, temp_filename, &options);
    av_dict_free(&options);
    if (ret < 0) {
        goto fail;
    }

    for (en = vs->segments; en; en = en->next) {
        if (target_duration <= en->duration)
            target_duration = lrint(en->duration);
    }