/*
  * Apple HTTP Live Streaming segmenter
  * Copyright (c) 2012, Luca Barbato

  * Copyright (c) 2017 Akamai Technologies, Inc.

  *

  * This file is part of FFmpeg.

  *

  * FFmpeg is free software; you can redistribute it and/or

  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *

  * FFmpeg is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public

  * License along with FFmpeg; if not, write to the Free Software

  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 

 #include "config.h"

 #include <float.h>

 #include <stdint.h>

 #if HAVE_UNISTD_H
 #include <unistd.h>
 #endif

 #if CONFIG_GCRYPT
 #include <gcrypt.h>
 #elif CONFIG_OPENSSL
 #include <openssl/rand.h>
 #endif
 

 #include "libavutil/avassert.h"

 #include "libavutil/mathematics.h"
 #include "libavutil/parseutils.h"
 #include "libavutil/avstring.h"

 #include "libavutil/intreadwrite.h"
 #include "libavutil/random_seed.h"

 #include "libavutil/opt.h"
 #include "libavutil/log.h"

 #include "libavutil/time.h"

 #include "libavutil/time_internal.h"

 
 #include "avformat.h"

 #include "avio_internal.h"

 #if CONFIG_HTTP_PROTOCOL

 #include "http.h"

 #endif

 #include "hlsplaylist.h"

 #include "internal.h"

 #include "os_support.h"

 typedef enum {

     HLS_START_SEQUENCE_AS_START_NUMBER = 0,
     HLS_START_SEQUENCE_AS_SECONDS_SINCE_EPOCH = 1,
     HLS_START_SEQUENCE_AS_FORMATTED_DATETIME = 2,  // YYYYMMDDhhmmss

     HLS_START_SEQUENCE_AS_MICROSECONDS_SINCE_EPOCH = 3,
     HLS_START_SEQUENCE_LAST, // unused

 } StartSequenceSourceType;
 

 typedef enum {
     CODEC_ATTRIBUTE_WRITTEN = 0,
     CODEC_ATTRIBUTE_WILL_NOT_BE_WRITTEN,
 } CodecAttributeStatus;
 

 #define KEYSIZE 16

 #define LINE_BUFFER_SIZE MAX_URL_SIZE

 #define HLS_MICROSECOND_UNIT   1000000

 #define POSTFIX_PATTERN "_%d"

 typedef struct HLSSegment {

     char filename[MAX_URL_SIZE];
     char sub_filename[MAX_URL_SIZE];

     double duration; /* in seconds */

     int discont;

     int64_t pos;
     int64_t size;

     int64_t keyframe_pos;
     int64_t keyframe_size;

     unsigned var_stream_idx;

     char key_uri[LINE_BUFFER_SIZE + 1];
     char iv_string[KEYSIZE*2 + 1];
 

     struct HLSSegment *next;
 } HLSSegment;

 typedef enum HLSFlags {
     // Generate a single media file and use byte ranges in the playlist.
     HLS_SINGLE_FILE = (1 << 0),

     HLS_DELETE_SEGMENTS = (1 << 1),

     HLS_ROUND_DURATIONS = (1 << 2),

     HLS_DISCONT_START = (1 << 3),

     HLS_OMIT_ENDLIST = (1 << 4),

     HLS_SPLIT_BY_TIME = (1 << 5),

     HLS_APPEND_LIST = (1 << 6),

     HLS_PROGRAM_DATE_TIME = (1 << 7),

     HLS_SECOND_LEVEL_SEGMENT_INDEX = (1 << 8), // include segment index in segment filenames when use_localtime  e.g.: %%03d

     HLS_SECOND_LEVEL_SEGMENT_DURATION = (1 << 9), // include segment duration (microsec) in segment filenames when use_localtime  e.g.: %%09t
     HLS_SECOND_LEVEL_SEGMENT_SIZE = (1 << 10), // include segment size (bytes) in segment filenames when use_localtime  e.g.: %%014s

     HLS_TEMP_FILE = (1 << 11),

     HLS_PERIODIC_REKEY = (1 << 12),

     HLS_INDEPENDENT_SEGMENTS = (1 << 13),

     HLS_I_FRAMES_ONLY = (1 << 14),

 } HLSFlags;
 

 typedef enum {

     SEGMENT_TYPE_MPEGTS,
     SEGMENT_TYPE_FMP4,
 } SegmentType;
 

 typedef struct VariantStream {

     unsigned var_stream_idx;

     unsigned number;

     int64_t sequence;

     ff_const59 AVOutputFormat *oformat;
     ff_const59 AVOutputFormat *vtt_oformat;

     AVIOContext *out;
     int packets_written;
     int init_range_length;

     uint8_t *temp_buffer;

     uint8_t *init_buffer;

     AVFormatContext *avf;

     AVFormatContext *vtt_avf;

     int has_video;

     int has_subtitle;

     int new_start;

     int start_pts_from_audio;

     double dpp;           // duration per packet

     int64_t start_pts;
     int64_t end_pts;

     int64_t video_lastpos;
     int64_t video_keyframe_pos;
     int64_t video_keyframe_size;

     double duration;      // last segment duration computed so far, in seconds

     int64_t start_pos;    // last segment starting position
     int64_t size;         // last segment size

     int nb_entries;

     int discontinuity_set;

     int discontinuity;

     int reference_stream_index;

     HLSSegment *segments;
     HLSSegment *last_segment;

     HLSSegment *old_segments;

     char *basename;

     char *vtt_basename;
     char *vtt_m3u8_name;

     char *m3u8_name;
 
     double initial_prog_date_time;

     char current_segment_final_filename_fmt[MAX_URL_SIZE]; // when renaming segments

 
     char *fmp4_init_filename;
     char *base_output_dirname;
 

     int encrypt_started;
 
     char key_file[LINE_BUFFER_SIZE + 1];
     char key_uri[LINE_BUFFER_SIZE + 1];
     char key_string[KEYSIZE*2 + 1];
     char iv_string[KEYSIZE*2 + 1];
 

     AVStream **streams;

     char codec_attr[128];
     CodecAttributeStatus attr_status;

     unsigned int nb_streams;

     int m3u8_created; /* status of media play-list creation */

     int is_default; /* default status of audio group */

     const char *language; /* audio lauguage name */
     const char *agroup;   /* audio group name */
     const char *sgroup;   /* subtitle group name */
     const char *ccgroup;  /* closed caption group name */
     const char *varname;  /* variant name */

 } VariantStream;
 

 typedef struct ClosedCaptionsStream {

     const char *ccgroup;    /* closed caption group name */
     const char *instreamid; /* closed captions INSTREAM-ID */
     const char *language;   /* closed captions langauge */

 } ClosedCaptionsStream;
 

 typedef struct HLSContext {
     const AVClass *class;  // Class for private options.
     int64_t start_sequence;
     uint32_t start_sequence_source_type;  // enum StartSequenceSourceType
 
     float time;            // Set by a private option.
     float init_time;       // Set by a private option.
     int max_nb_segments;   // Set by a private option.

     int hls_delete_threshold; // Set by a private option.

 #if FF_API_HLS_WRAP
     int  wrap;             // Set by a private option.
 #endif
     uint32_t flags;        // enum HLSFlags
     uint32_t pl_type;      // enum PlaylistType
     char *segment_filename;
     char *fmp4_init_filename;
     int segment_type;

     int resend_init_file;  ///< resend init file into disk after refresh m3u8

 
     int use_localtime;      ///< flag to expand filename with localtime
     int use_localtime_mkdir;///< flag to mkdir dirname in timebased filename
     int allowcache;
     int64_t recording_time;
     int64_t max_seg_size; // every segment file max size
 

     char *baseurl;

     char *vtt_format_options_str;
     char *subtitle_filename;

     AVDictionary *format_options;

     int encrypt;
     char *key;
     char *key_url;
     char *iv;
     char *key_basename;

     int encrypt_started;

     char *key_info_file;
     char key_file[LINE_BUFFER_SIZE + 1];
     char key_uri[LINE_BUFFER_SIZE + 1];
     char key_string[KEYSIZE*2 + 1];
     char iv_string[KEYSIZE*2 + 1];

     AVDictionary *vtt_format_options;
 

     char *method;

     char *user_agent;

 
     VariantStream *var_streams;
     unsigned int nb_varstreams;

     ClosedCaptionsStream *cc_streams;
     unsigned int nb_ccstreams;

 
     int master_m3u8_created; /* status of master play-list creation */
     char *master_m3u8_url; /* URL of the master m3u8 file */
     int version; /* HLS version */

     char *var_stream_map; /* user specified variant stream map string */

     char *cc_stream_map; /* user specified closed caption streams map string */

     char *master_pl_name;
     unsigned int master_publish_rate;

     int http_persistent;

     AVIOContext *m3u8_out;
     AVIOContext *sub_m3u8_out;

     int64_t timeout;

     int ignore_io_errors;

     char *headers;

     int has_default_key; /* has DEFAULT field of var_stream_map */
     int has_video_m3u8; /* has video stream m3u8 list */

 } HLSContext;
 

 static int hlsenc_io_open(AVFormatContext *s, AVIOContext **pb, char *filename,

                           AVDictionary **options)
 {

     HLSContext *hls = s->priv_data;

     int http_base_proto = filename ? ff_is_http_proto(filename) : 0;

     int err = AVERROR_MUXER_NOT_FOUND;

     if (!*pb || !http_base_proto || !hls->http_persistent) {
         err = s->io_open(s, pb, filename, AVIO_FLAG_WRITE, options);

 #if CONFIG_HTTP_PROTOCOL

     } else {
         URLContext *http_url_context = ffio_geturlcontext(*pb);
         av_assert0(http_url_context);
         err = ff_http_do_new_request(http_url_context, filename);

         if (err < 0)
             ff_format_io_close(s, pb);
 

 #endif

     }
     return err;
 }
 

 static int hlsenc_io_close(AVFormatContext *s, AVIOContext **pb, char *filename)
 {

     HLSContext *hls = s->priv_data;

     int http_base_proto = filename ? ff_is_http_proto(filename) : 0;

     int ret = 0;

     if (!*pb)

         return ret;

     if (!http_base_proto || !hls->http_persistent || hls->key_info_file || hls->encrypt) {
         ff_format_io_close(s, pb);

 #if CONFIG_HTTP_PROTOCOL

     } else {

         URLContext *http_url_context = ffio_geturlcontext(*pb);
         av_assert0(http_url_context);

         avio_flush(*pb);

         ffurl_shutdown(http_url_context, AVIO_FLAG_WRITE);

         ret = ff_http_get_shutdown_status(http_url_context);

 #endif

     }

     return ret;

 }
 

 static void set_http_options(AVFormatContext *s, AVDictionary **options, HLSContext *c)
 {

     int http_base_proto = ff_is_http_proto(s->url);

 
     if (c->method) {
         av_dict_set(options, "method", c->method, 0);
     } else if (http_base_proto) {
         av_dict_set(options, "method", "PUT", 0);
     }
     if (c->user_agent)
         av_dict_set(options, "user_agent", c->user_agent, 0);

     if (c->http_persistent)
         av_dict_set_int(options, "multiple_requests", 1, 0);

     if (c->timeout >= 0)
         av_dict_set_int(options, "timeout", c->timeout, 0);

     if (c->headers)
         av_dict_set(options, "headers", c->headers, 0);

 }
 

 static void write_codec_attr(AVStream *st, VariantStream *vs)
 {

     int codec_strlen = strlen(vs->codec_attr);
     char attr[32];
 
     if (st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE)
         return;
     if (vs->attr_status == CODEC_ATTRIBUTE_WILL_NOT_BE_WRITTEN)
         return;
 
     if (st->codecpar->codec_id == AV_CODEC_ID_H264) {
         uint8_t *data = st->codecpar->extradata;

         if (data && (data[0] | data[1] | data[2]) == 0 && data[3] == 1 && (data[4] & 0x1F) == 7) {

             snprintf(attr, sizeof(attr),
                      "avc1.%02x%02x%02x", data[5], data[6], data[7]);
         } else {
             goto fail;
         }
     } else if (st->codecpar->codec_id == AV_CODEC_ID_MP2) {
         snprintf(attr, sizeof(attr), "mp4a.40.33");
     } else if (st->codecpar->codec_id == AV_CODEC_ID_MP3) {
         snprintf(attr, sizeof(attr), "mp4a.40.34");
     } else if (st->codecpar->codec_id == AV_CODEC_ID_AAC) {
         /* TODO : For HE-AAC, HE-AACv2, the last digit needs to be set to 5 and 29 respectively */
         snprintf(attr, sizeof(attr), "mp4a.40.2");
     } else if (st->codecpar->codec_id == AV_CODEC_ID_AC3) {
         snprintf(attr, sizeof(attr), "ac-3");
     } else if (st->codecpar->codec_id == AV_CODEC_ID_EAC3) {
         snprintf(attr, sizeof(attr), "ec-3");
     } else {
         goto fail;
     }
     // Don't write the same attribute multiple times
     if (!av_stristr(vs->codec_attr, attr)) {
         snprintf(vs->codec_attr + codec_strlen,
                  sizeof(vs->codec_attr) - codec_strlen,
                  "%s%s", codec_strlen ? "," : "", attr);
     }
     return;
 
 fail:
     vs->codec_attr[0] = '\0';
     vs->attr_status = CODEC_ATTRIBUTE_WILL_NOT_BE_WRITTEN;
     return;
 }
 

 static int replace_str_data_in_filename(char **s, const char *filename, char placeholder, const char *datastring)
 {
     const char *p;
     char *new_filename;
     char c;
     int addchar_count;
     int found_count = 0;
     AVBPrint buf;
 
     av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);
 
     p = filename;
     for (;;) {
         c = *p;
         if (c == '\0')
             break;
         if (c == '%' && *(p+1) == '%')  // %%
             addchar_count = 2;
         else if (c == '%' && *(p+1) == placeholder) {
             av_bprintf(&buf, "%s", datastring);
             p += 2;
             addchar_count = 0;
             found_count ++;
         } else
             addchar_count = 1;
 
         if (addchar_count > 0) {
             av_bprint_append_data(&buf, p, addchar_count);
             p += addchar_count;
         }
     }
     if (!av_bprint_is_complete(&buf)) {
         av_bprint_finalize(&buf, NULL);
         return -1;
     }
     if (av_bprint_finalize(&buf, &new_filename) < 0 || !new_filename)
         return -1;
     *s = new_filename;
     return found_count;
 }
 

 static int replace_int_data_in_filename(char **s, const char *filename, char placeholder, int64_t number)

 {
     const char *p;

     char *new_filename;
     char c;
     int nd, addchar_count;

     int found_count = 0;

     AVBPrint buf;
 
     av_bprint_init(&buf, 0, AV_BPRINT_SIZE_UNLIMITED);

 
     p = filename;
     for (;;) {
         c = *p;
         if (c == '\0')
             break;
         if (c == '%' && *(p+1) == '%')  // %%
             addchar_count = 2;
         else if (c == '%' && (av_isdigit(*(p+1)) || *(p+1) == placeholder)) {
             nd = 0;
             addchar_count = 1;
             while (av_isdigit(*(p + addchar_count))) {
                 nd = nd * 10 + *(p + addchar_count) - '0';
                 addchar_count++;
             }
 
             if (*(p + addchar_count) == placeholder) {

                 av_bprintf(&buf, "%0*"PRId64, (number < 0) ? nd : nd++, number);

                 p += (addchar_count + 1);
                 addchar_count = 0;
                 found_count++;
             }
 
         } else
             addchar_count = 1;
 

         av_bprint_append_data(&buf, p, addchar_count);
         p += addchar_count;

     }

     if (!av_bprint_is_complete(&buf)) {
         av_bprint_finalize(&buf, NULL);
         return -1;
     }
     if (av_bprint_finalize(&buf, &new_filename) < 0 || !new_filename)
         return -1;
     *s = new_filename;

     return found_count;
 }
 

 static void write_styp(AVIOContext *pb)
 {
     avio_wb32(pb, 24);
     ffio_wfourcc(pb, "styp");
     ffio_wfourcc(pb, "msdh");
     avio_wb32(pb, 0); /* minor */
     ffio_wfourcc(pb, "msdh");
     ffio_wfourcc(pb, "msix");
 }
 

 static int flush_dynbuf(VariantStream *vs, int *range_length)
 {
     AVFormatContext *ctx = vs->avf;
 
     if (!ctx->pb) {
         return AVERROR(EINVAL);
     }
 
     // flush
     av_write_frame(ctx, NULL);
 
     // write out to file

     *range_length = avio_close_dyn_buf(ctx->pb, &vs->temp_buffer);

     ctx->pb = NULL;

     avio_write(vs->out, vs->temp_buffer, *range_length);

     avio_flush(vs->out);

 
     // re-open buffer
     return avio_open_dyn_buf(&ctx->pb);
 }
 

 static void reflush_dynbuf(VariantStream *vs, int *range_length)
 {
     // re-open buffer

     avio_write(vs->out, vs->temp_buffer, *range_length);

 }
 

 #if HAVE_DOS_PATHS
 #define SEPARATOR '\\'
 #else
 #define SEPARATOR '/'
 #endif
 

 static int hls_delete_file(HLSContext *hls, AVFormatContext *avf,
                            const char *path, const char *proto)
 {
     if (hls->method || (proto && !av_strcasecmp(proto, "http"))) {
         AVDictionary *opt = NULL;
         AVIOContext  *out = NULL;
         int ret;
         av_dict_set(&opt, "method", "DELETE", 0);
         ret = avf->io_open(avf, &out, path, AVIO_FLAG_WRITE, &opt);
         av_dict_free(&opt);
         if (ret < 0)
             return hls->ignore_io_errors ? 1 : ret;
         ff_format_io_close(avf, &out);
     } else if (unlink(path) < 0) {
         av_log(hls, AV_LOG_ERROR, "failed to delete old segment %s: %s\n",
                path, strerror(errno));
     }
     return 0;
 }
 

 static int hls_delete_old_segments(AVFormatContext *s, HLSContext *hls,

                                    VariantStream *vs)
 {

 
     HLSSegment *segment, *previous_segment = NULL;
     float playlist_duration = 0.0f;

     int ret = 0;

     int segment_cnt = 0;

     AVBPrint path;

     const char *dirname = NULL;

     char *dirname_r = NULL;
     char *dirname_repl = NULL;

     const char *vtt_dirname = NULL;

     char *vtt_dirname_r = NULL;

     const char *proto = NULL;

     av_bprint_init(&path, 0, AV_BPRINT_SIZE_UNLIMITED);
 

     segment = vs->segments;

     while (segment) {
         playlist_duration += segment->duration;
         segment = segment->next;
     }
 

     segment = vs->old_segments;

     segment_cnt = 0;

     while (segment) {
         playlist_duration -= segment->duration;
         previous_segment = segment;
         segment = previous_segment->next;

         segment_cnt++;

         if (playlist_duration <= -previous_segment->duration) {
             previous_segment->next = NULL;
             break;
         }

         if (segment_cnt >= hls->hls_delete_threshold) {
             previous_segment->next = NULL;
             break;
         }

     }
 

     if (segment && !hls->use_localtime_mkdir) {

         dirname_r = hls->segment_filename ? av_strdup(hls->segment_filename): av_strdup(vs->avf->url);

         dirname = av_dirname(dirname_r);

     }
 

     /* if %v is present in the file's directory
      * all segment belongs to the same variant, so do it only once before the loop*/
     if (dirname && av_stristr(dirname, "%v")) {
         if (!vs->varname) {

             if (replace_int_data_in_filename(&dirname_repl, dirname, 'v', segment->var_stream_idx) < 1) {

                 ret = AVERROR(EINVAL);
                 goto fail;
             }

         } else {

             if (replace_str_data_in_filename(&dirname_repl, dirname, 'v', vs->varname) < 1) {

                 ret = AVERROR(EINVAL);
                 goto fail;
             }

         }
 

         dirname = dirname_repl;

     }
 
     while (segment) {

         av_log(hls, AV_LOG_DEBUG, "deleting old segment %s\n",

                segment->filename);

         if (!hls->use_localtime_mkdir) // segment->filename contains basename only
             av_bprintf(&path, "%s%c", dirname, SEPARATOR);
         av_bprintf(&path, "%s", segment->filename);
 
         if (!av_bprint_is_complete(&path)) {

             ret = AVERROR(ENOMEM);
             goto fail;
         }

         proto = avio_find_protocol_name(s->url);

         if (ret = hls_delete_file(hls, vs->avf, path.str, proto))
             goto fail;

         if ((segment->sub_filename[0] != '\0')) {

             vtt_dirname_r = av_strdup(vs->vtt_avf->url);

             vtt_dirname = av_dirname(vtt_dirname_r);

 
             av_bprint_clear(&path);
             av_bprintf(&path, "%s%c%s", vtt_dirname, SEPARATOR,
                                          segment->sub_filename);
             av_freep(&vtt_dirname_r);
 
             if (!av_bprint_is_complete(&path)) {

                 ret = AVERROR(ENOMEM);
                 goto fail;
             }
 

             if (ret = hls_delete_file(hls, vs->vtt_avf, path.str, proto))
                 goto fail;

         }

         av_bprint_clear(&path);

         previous_segment = segment;
         segment = previous_segment->next;

         av_freep(&previous_segment);

     }
 
 fail:

     av_bprint_finalize(&path, NULL);

     av_freep(&dirname_r);
     av_freep(&dirname_repl);

 
     return ret;
 }
 

 static int randomize(uint8_t *buf, int len)
 {
 #if CONFIG_GCRYPT
     gcry_randomize(buf, len, GCRY_VERY_STRONG_RANDOM);
     return 0;
 #elif CONFIG_OPENSSL
     if (RAND_bytes(buf, len))
         return 0;
 #else
     return AVERROR(ENOSYS);
 #endif
     return AVERROR(EINVAL);
 }
 

 static int do_encrypt(AVFormatContext *s, VariantStream *vs)

 {
     HLSContext *hls = s->priv_data;
     int ret;
     int len;
     AVIOContext *pb;
     uint8_t key[KEYSIZE];

     char * key_basename_source = (hls->master_m3u8_url) ? hls->master_m3u8_url : s->url;

     len = strlen(key_basename_source) + 4 + 1;

     hls->key_basename = av_mallocz(len);
     if (!hls->key_basename)
         return AVERROR(ENOMEM);
 

     av_strlcpy(hls->key_basename, key_basename_source, len);

     av_strlcat(hls->key_basename, ".key", len);
 
     if (hls->key_url) {

         av_strlcpy(hls->key_file, hls->key_url, sizeof(hls->key_file));
         av_strlcpy(hls->key_uri, hls->key_url, sizeof(hls->key_uri));

     } else {

         av_strlcpy(hls->key_file, hls->key_basename, sizeof(hls->key_file));
         av_strlcpy(hls->key_uri, hls->key_basename, sizeof(hls->key_uri));

     }
 
     if (!*hls->iv_string) {
         uint8_t iv[16] = { 0 };
         char buf[33];
 
         if (!hls->iv) {

             AV_WB64(iv + 8, vs->sequence);

         } else {
             memcpy(iv, hls->iv, sizeof(iv));
         }
         ff_data_to_hex(buf, iv, sizeof(iv), 0);
         buf[32] = '\0';
         memcpy(hls->iv_string, buf, sizeof(hls->iv_string));
     }
 
     if (!*hls->key_uri) {
         av_log(hls, AV_LOG_ERROR, "no key URI specified in key info file\n");
         return AVERROR(EINVAL);
     }
 
     if (!*hls->key_file) {
         av_log(hls, AV_LOG_ERROR, "no key file specified in key info file\n");
         return AVERROR(EINVAL);
     }
 
     if (!*hls->key_string) {

         AVDictionary *options = NULL;

         if (!hls->key) {
             if ((ret = randomize(key, sizeof(key))) < 0) {
                 av_log(s, AV_LOG_ERROR, "Cannot generate a strong random key\n");
                 return ret;
             }
         } else {
             memcpy(key, hls->key, sizeof(key));
         }
 
         ff_data_to_hex(hls->key_string, key, sizeof(key), 0);

         set_http_options(s, &options, hls);
         ret = s->io_open(s, &pb, hls->key_file, AVIO_FLAG_WRITE, &options);
         av_dict_free(&options);
         if (ret < 0)

             return ret;
         avio_seek(pb, 0, SEEK_CUR);
         avio_write(pb, key, KEYSIZE);
         avio_close(pb);
     }
     return 0;
 }
 
 

 static int hls_encryption_start(AVFormatContext *s,  VariantStream *vs)

 {
     HLSContext *hls = s->priv_data;
     int ret;
     AVIOContext *pb;
     uint8_t key[KEYSIZE];

     AVDictionary *options = NULL;

     set_http_options(s, &options, hls);
     ret = s->io_open(s, &pb, hls->key_info_file, AVIO_FLAG_READ, &options);
     av_dict_free(&options);
     if (ret < 0) {

         av_log(hls, AV_LOG_ERROR,

                "error opening key info file %s\n", hls->key_info_file);

         return ret;
     }
 

     ff_get_line(pb, vs->key_uri, sizeof(vs->key_uri));
     vs->key_uri[strcspn(vs->key_uri, "\r\n")] = '\0';

     ff_get_line(pb, vs->key_file, sizeof(vs->key_file));
     vs->key_file[strcspn(vs->key_file, "\r\n")] = '\0';

     ff_get_line(pb, vs->iv_string, sizeof(vs->iv_string));
     vs->iv_string[strcspn(vs->iv_string, "\r\n")] = '\0';

     ff_format_io_close(s, &pb);

     if (!*vs->key_uri) {

         av_log(hls, AV_LOG_ERROR, "no key URI specified in key info file\n");
         return AVERROR(EINVAL);
     }
 

     if (!*vs->key_file) {

         av_log(hls, AV_LOG_ERROR, "no key file specified in key info file\n");
         return AVERROR(EINVAL);
     }
 

     set_http_options(s, &options, hls);

     ret = s->io_open(s, &pb, vs->key_file, AVIO_FLAG_READ, &options);

     av_dict_free(&options);
     if (ret < 0) {

         av_log(hls, AV_LOG_ERROR, "error opening key file %s\n", vs->key_file);

         return ret;
     }
 
     ret = avio_read(pb, key, sizeof(key));

     ff_format_io_close(s, &pb);

     if (ret != sizeof(key)) {

         av_log(hls, AV_LOG_ERROR, "error reading key file %s\n", vs->key_file);

         if (ret >= 0 || ret == AVERROR_EOF)
             ret = AVERROR(EINVAL);
         return ret;
     }

     ff_data_to_hex(vs->key_string, key, sizeof(key), 0);

 
     return 0;
 }
 

 static int hls_mux_init(AVFormatContext *s, VariantStream *vs)

 {

     AVDictionary *options = NULL;

     HLSContext *hls = s->priv_data;
     AVFormatContext *oc;

     AVFormatContext *vtt_oc = NULL;

     int byterange_mode = (hls->flags & HLS_SINGLE_FILE) || (hls->max_seg_size > 0);

     int remaining_options;

     int i, ret;

     ret = avformat_alloc_output_context2(&vs->avf, vs->oformat, NULL, NULL);

     if (ret < 0)
         return ret;

     oc = vs->avf;

     oc->url                = av_strdup("");
     if (!oc->url)
         return AVERROR(ENOMEM);
 

     oc->interrupt_callback       = s->interrupt_callback;
     oc->max_delay                = s->max_delay;
     oc->opaque                   = s->opaque;
     oc->io_open                  = s->io_open;
     oc->io_close                 = s->io_close;
     oc->strict_std_compliance    = s->strict_std_compliance;

     av_dict_copy(&oc->metadata, s->metadata, 0);

     if (vs->vtt_oformat) {

         ret = avformat_alloc_output_context2(&vs->vtt_avf, vs->vtt_oformat, NULL, NULL);

         if (ret < 0)
             return ret;

         vtt_oc          = vs->vtt_avf;

         av_dict_copy(&vtt_oc->metadata, s->metadata, 0);
     }
 

     for (i = 0; i < vs->nb_streams; i++) {

         AVStream *st;

         AVFormatContext *loc;

         if (vs->streams[i]->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE)

             loc = vtt_oc;
         else
             loc = oc;
 
         if (!(st = avformat_new_stream(loc, NULL)))

             return AVERROR(ENOMEM);

         avcodec_parameters_copy(st->codecpar, vs->streams[i]->codecpar);

         if (!oc->oformat->codec_tag ||

             av_codec_get_id (oc->oformat->codec_tag, vs->streams[i]->codecpar->codec_tag) == st->codecpar->codec_id ||
             av_codec_get_tag(oc->oformat->codec_tag, vs->streams[i]->codecpar->codec_id) <= 0) {
             st->codecpar->codec_tag = vs->streams[i]->codecpar->codec_tag;

         } else {
             st->codecpar->codec_tag = 0;
         }
 

         st->sample_aspect_ratio = vs->streams[i]->sample_aspect_ratio;
         st->time_base = vs->streams[i]->time_base;
         av_dict_copy(&st->metadata, vs->streams[i]->metadata, 0);

     }

 
     vs->start_pos = 0;
     vs->new_start = 1;

     if (hls->segment_type == SEGMENT_TYPE_FMP4 && hls->max_seg_size > 0) {

         if (hls->http_persistent > 0) {
             //TODO: Support fragment fmp4 for http persistent in HLS muxer.
             av_log(s, AV_LOG_WARNING, "http persistent mode is currently unsupported for fragment mp4 in the HLS muxer.\n");
         }

         if (hls->max_seg_size > 0) {
             av_log(s, AV_LOG_WARNING, "Multi-file byterange mode is currently unsupported in the HLS muxer.\n");
             return AVERROR_PATCHWELCOME;
         }

     }

     if ((ret = avio_open_dyn_buf(&oc->pb)) < 0)
         return ret;

     if (hls->segment_type == SEGMENT_TYPE_FMP4) {

         set_http_options(s, &options, hls);

         if (byterange_mode) {
             ret = hlsenc_io_open(s, &vs->out, vs->basename, &options);
         } else {
             ret = hlsenc_io_open(s, &vs->out, vs->base_output_dirname, &options);
         }

         av_dict_free(&options);

     }
     if (ret < 0) {
         av_log(s, AV_LOG_ERROR, "Failed to open segment '%s'\n", vs->fmp4_init_filename);
         return ret;
     }
 

     av_dict_copy(&options, hls->format_options, 0);

     if (hls->segment_type == SEGMENT_TYPE_FMP4) {

         av_dict_set(&options, "fflags", "-autobsf", 0);

         av_dict_set(&options, "movflags", "+frag_custom+dash+delay_moov", AV_DICT_APPEND);

     } else {
         /* We only require one PAT/PMT per segment. */
         char period[21];
         snprintf(period, sizeof(period), "%d", (INT_MAX / 2) - 1);

         av_dict_set(&options, "sdt_period", period, AV_DICT_DONT_OVERWRITE);
         av_dict_set(&options, "pat_period", period, AV_DICT_DONT_OVERWRITE);

     }
     ret = avformat_init_output(oc, &options);
     remaining_options = av_dict_count(options);
     av_dict_free(&options);
     if (ret < 0)
         return ret;
     if (remaining_options) {
         av_log(s, AV_LOG_ERROR, "Some of the provided format options are not recognized\n");
         return AVERROR(EINVAL);

     }

     avio_flush(oc->pb);

     return 0;
 }
 

 static HLSSegment *find_segment_by_filename(HLSSegment *segment, const char *filename)
 {
     while (segment) {
         if (!av_strcasecmp(segment->filename,filename))
             return segment;
         segment = segment->next;
     }
     return (HLSSegment *) NULL;
 }
 

 static int sls_flags_filename_process(struct AVFormatContext *s, HLSContext *hls,
                                       VariantStream *vs, HLSSegment *en,
                                       double duration, int64_t pos, int64_t size)

 {

     if ((hls->flags & (HLS_SECOND_LEVEL_SEGMENT_SIZE | HLS_SECOND_LEVEL_SEGMENT_DURATION)) &&

         strlen(vs->current_segment_final_filename_fmt)) {

         char * new_url = av_strdup(vs->current_segment_final_filename_fmt);
         if (!new_url) {
             return AVERROR(ENOMEM);
         }
         ff_format_set_url(vs->avf, new_url);

         if (hls->flags & HLS_SECOND_LEVEL_SEGMENT_SIZE) {

             char *filename = NULL;

             if (replace_int_data_in_filename(&filename, vs->avf->url, 's', pos + size) < 1) {

                 av_log(hls, AV_LOG_ERROR,
                        "Invalid second level segment filename template '%s', "

                        "you can try to remove second_level_segment_size flag\n",

                        vs->avf->url);

                 av_freep(&filename);

                 return AVERROR(EINVAL);
             }

             ff_format_set_url(vs->avf, filename);

         }
         if (hls->flags & HLS_SECOND_LEVEL_SEGMENT_DURATION) {

             char *filename = NULL;

             if (replace_int_data_in_filename(&filename, vs->avf->url,

                                              't',  (int64_t)round(duration * HLS_MICROSECOND_UNIT)) < 1) {

                 av_log(hls, AV_LOG_ERROR,
                        "Invalid second level segment filename template '%s', "

                        "you can try to remove second_level_segment_time flag\n",

                        vs->avf->url);

                 av_freep(&filename);

                 return AVERROR(EINVAL);
             }

             ff_format_set_url(vs->avf, filename);

         }
     }

     return 0;
 }
 
 static int sls_flag_check_duration_size_index(HLSContext *hls)
 {
     int ret = 0;
 
     if (hls->flags & HLS_SECOND_LEVEL_SEGMENT_DURATION) {

         av_log(hls, AV_LOG_ERROR,
                "second_level_segment_duration hls_flag requires strftime to be true\n");
         ret = AVERROR(EINVAL);

     }
     if (hls->flags & HLS_SECOND_LEVEL_SEGMENT_SIZE) {

         av_log(hls, AV_LOG_ERROR,
                "second_level_segment_size hls_flag requires strfime to be true\n");
         ret = AVERROR(EINVAL);

     }
     if (hls->flags & HLS_SECOND_LEVEL_SEGMENT_INDEX) {
         av_log(hls, AV_LOG_ERROR,

                "second_level_segment_index hls_flag requires strftime to be true\n");

         ret = AVERROR(EINVAL);
     }
 
     return ret;
 }
 

 static int sls_flag_check_duration_size(HLSContext *hls, VariantStream *vs)

 {

     const char *proto = avio_find_protocol_name(vs->basename);

     int segment_renaming_ok = proto && !strcmp(proto, "file");
     int ret = 0;
 
     if ((hls->flags & HLS_SECOND_LEVEL_SEGMENT_DURATION) && !segment_renaming_ok) {

         av_log(hls, AV_LOG_ERROR,
                "second_level_segment_duration hls_flag works only with file protocol segment names\n");
         ret = AVERROR(EINVAL);

     }
     if ((hls->flags & HLS_SECOND_LEVEL_SEGMENT_SIZE) && !segment_renaming_ok) {

         av_log(hls, AV_LOG_ERROR,
                "second_level_segment_size hls_flag works only with file protocol segment names\n");
         ret = AVERROR(EINVAL);

     }
 
     return ret;
 }
 

 static void sls_flag_file_rename(HLSContext *hls, VariantStream *vs, char *old_filename) {

     if ((hls->flags & (HLS_SECOND_LEVEL_SEGMENT_SIZE | HLS_SECOND_LEVEL_SEGMENT_DURATION)) &&

         strlen(vs->current_segment_final_filename_fmt)) {

         ff_rename(old_filename, vs->avf->url, hls);

     }
 }
 

 static int sls_flag_use_localtime_filename(AVFormatContext *oc, HLSContext *c, VariantStream *vs)

 {
     if (c->flags & HLS_SECOND_LEVEL_SEGMENT_INDEX) {

         char *filename = NULL;
         if (replace_int_data_in_filename(&filename,

 #if FF_API_HLS_WRAP

             oc->url, 'd', c->wrap ? vs->sequence % c->wrap : vs->sequence) < 1) {

 #else

             oc->url, 'd', vs->sequence) < 1) {

 #endif
             av_log(c, AV_LOG_ERROR, "Invalid second level segment filename template '%s', "
                     "you can try to remove second_level_segment_index flag\n",

                    oc->url);

             av_freep(&filename);

             return AVERROR(EINVAL);
         }

         ff_format_set_url(oc, filename);

     }
     if (c->flags & (HLS_SECOND_LEVEL_SEGMENT_SIZE | HLS_SECOND_LEVEL_SEGMENT_DURATION)) {

         av_strlcpy(vs->current_segment_final_filename_fmt, oc->url,

                    sizeof(vs->current_segment_final_filename_fmt));

         if (c->flags & HLS_SECOND_LEVEL_SEGMENT_SIZE) {

             char *filename = NULL;

             if (replace_int_data_in_filename(&filename, oc->url, 's', 0) < 1) {

                 av_log(c, AV_LOG_ERROR, "Invalid second level segment filename template '%s', "
                         "you can try to remove second_level_segment_size flag\n",

                        oc->url);

                 av_freep(&filename);

                 return AVERROR(EINVAL);
             }

             ff_format_set_url(oc, filename);

         }
         if (c->flags & HLS_SECOND_LEVEL_SEGMENT_DURATION) {

             char *filename = NULL;

             if (replace_int_data_in_filename(&filename, oc->url, 't', 0) < 1) {

                 av_log(c, AV_LOG_ERROR, "Invalid second level segment filename template '%s', "
                         "you can try to remove second_level_segment_time flag\n",

                        oc->url);

                 av_freep(&filename);

                 return AVERROR(EINVAL);
             }

             ff_format_set_url(oc, filename);

         }
     }
     return 0;
 }
 
 /* Create a new segment and append it to the segment list */

 static int hls_append_segment(struct AVFormatContext *s, HLSContext *hls,
                               VariantStream *vs, double duration, int64_t pos,
                               int64_t size)

 {
     HLSSegment *en = av_malloc(sizeof(*en));
     const char  *filename;

     int byterange_mode = (hls->flags & HLS_SINGLE_FILE) || (hls->max_seg_size > 0);

     int ret;

     if (!en)
         return AVERROR(ENOMEM);
 

     en->var_stream_idx = vs->var_stream_idx;

     ret = sls_flags_filename_process(s, hls, vs, en, duration, pos, size);

     if (ret < 0) {

         av_freep(&en);

         return ret;
     }

     filename = av_basename(vs->avf->url);

 
     if (hls->use_localtime_mkdir) {

         filename = vs->avf->url;

     }

     if ((find_segment_by_filename(vs->segments, filename) || find_segment_by_filename(vs->old_segments, filename))

         && !byterange_mode) {

         av_log(hls, AV_LOG_WARNING, "Duplicated segment filename detected: %s\n", filename);
     }

     av_strlcpy(en->filename, filename, sizeof(en->filename));

     if (vs->has_subtitle)

         av_strlcpy(en->sub_filename, av_basename(vs->vtt_avf->url), sizeof(en->sub_filename));

     else
         en->sub_filename[0] = '\0';

     en->duration = duration;

     en->pos      = pos;
     en->size     = size;

     en->keyframe_pos      = vs->video_keyframe_pos;
     en->keyframe_size     = vs->video_keyframe_size;

     en->next     = NULL;

     en->discont  = 0;
 

     if (vs->discontinuity) {

         en->discont = 1;

         vs->discontinuity = 0;

     }

     if (hls->key_info_file || hls->encrypt) {

         av_strlcpy(en->key_uri, vs->key_uri, sizeof(en->key_uri));
         av_strlcpy(en->iv_string, vs->iv_string, sizeof(en->iv_string));

     }
 

     if (!vs->segments)
         vs->segments = en;

     else

         vs->last_segment->next = en;

     vs->last_segment = en;

     // EVENT or VOD playlists imply sliding window cannot be used
     if (hls->pl_type != PLAYLIST_TYPE_NONE)
         hls->max_nb_segments = 0;
 

     if (hls->max_nb_segments && vs->nb_entries >= hls->max_nb_segments) {
         en = vs->segments;
         vs->initial_prog_date_time += en->duration;
         vs->segments = en->next;

         if (en && hls->flags & HLS_DELETE_SEGMENTS &&

 #if FF_API_HLS_WRAP

                 !(hls->flags & HLS_SINGLE_FILE || hls->wrap)) {

 #else
                 !(hls->flags & HLS_SINGLE_FILE)) {
 #endif

             en->next = vs->old_segments;
             vs->old_segments = en;
             if ((ret = hls_delete_old_segments(s, hls, vs)) < 0)

                 return ret;
         } else

             av_freep(&en);

     } else

         vs->nb_entries++;

     if (hls->max_seg_size > 0) {
         return 0;
     }

     vs->sequence++;

     return 0;
 }
 

 static int parse_playlist(AVFormatContext *s, const char *url, VariantStream *vs)

 {
     HLSContext *hls = s->priv_data;
     AVIOContext *in;
     int ret = 0, is_segment = 0;
     int64_t new_start_pos;

     char line[MAX_URL_SIZE];

     const char *ptr;

     const char *end;

 
     if ((ret = ffio_open_whitelist(&in, url, AVIO_FLAG_READ,
                                    &s->interrupt_callback, NULL,
                                    s->protocol_whitelist, s->protocol_blacklist)) < 0)
         return ret;
 

     ff_get_chomp_line(in, line, sizeof(line));

     if (strcmp(line, "#EXTM3U")) {
         ret = AVERROR_INVALIDDATA;
         goto fail;
     }
 

     vs->discontinuity = 0;

     while (!avio_feof(in)) {

         ff_get_chomp_line(in, line, sizeof(line));

         if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {

             int64_t tmp_sequence = strtoll(ptr, NULL, 10);

             if (tmp_sequence < vs->sequence)

               av_log(hls, AV_LOG_VERBOSE,
                      "Found playlist sequence number was smaller """
                      "than specified start sequence number: %"PRId64" < %"PRId64", "
                      "omitting\n", tmp_sequence, hls->start_sequence);
             else {
               av_log(hls, AV_LOG_DEBUG, "Found playlist sequence number: %"PRId64"\n", tmp_sequence);

               vs->sequence = tmp_sequence;

             }

         } else if (av_strstart(line, "#EXT-X-DISCONTINUITY", &ptr)) {
             is_segment = 1;

             vs->discontinuity = 1;

         } else if (av_strstart(line, "#EXTINF:", &ptr)) {
             is_segment = 1;

             vs->duration = atof(ptr);

         } else if (av_stristart(line, "#EXT-X-KEY:", &ptr)) {
             ptr = av_stristr(line, "URI=\"");
             if (ptr) {
                 ptr += strlen("URI=\"");
                 end = av_stristr(ptr, ",");
                 if (end) {

                     av_strlcpy(vs->key_uri, ptr, end - ptr);

                 } else {

                     av_strlcpy(vs->key_uri, ptr, sizeof(vs->key_uri));

                 }
             }
 
             ptr = av_stristr(line, "IV=0x");
             if (ptr) {
                 ptr += strlen("IV=0x");
                 end = av_stristr(ptr, ",");
                 if (end) {

                     av_strlcpy(vs->iv_string, ptr, end - ptr);

                 } else {

                     av_strlcpy(vs->iv_string, ptr, sizeof(vs->iv_string));

                 }
             }
 

         } else if (av_strstart(line, "#", NULL)) {
             continue;
         } else if (line[0]) {
             if (is_segment) {

                 char *new_file = av_strdup(line);
                 if (!new_file) {
                     ret = AVERROR(ENOMEM);
                     goto fail;
                 }
                 ff_format_set_url(vs->avf, new_file);

                 is_segment = 0;

                 new_start_pos = avio_tell(vs->avf->pb);
                 vs->size = new_start_pos - vs->start_pos;

                 vs->initial_prog_date_time -= vs->duration; // this is a previously existing segment

                 ret = hls_append_segment(s, hls, vs, vs->duration, vs->start_pos, vs->size);

                 if (ret < 0)
                     goto fail;

                 vs->start_pos = new_start_pos;

             }
         }
     }
 
 fail:
     avio_close(in);
     return ret;
 }
 

 static void hls_free_segments(HLSSegment *p)

 {

     HLSSegment *en;

     while (p) {

         en = p;
         p = p->next;

         av_freep(&en);

     }
 }
 

 static int hls_rename_temp_file(AVFormatContext *s, AVFormatContext *oc)

 {

     size_t len = strlen(oc->url);
     char *final_filename = av_strdup(oc->url);
     int ret;

     if (!final_filename)
         return AVERROR(ENOMEM);

     final_filename[len-4] = '\0';

     ret = ff_rename(oc->url, final_filename, s);
     oc->url[len-4] = '\0';
     av_freep(&final_filename);
     return ret;

 }
 

 static const char* get_relative_url(const char *master_url, const char *media_url)

 {

     const char *p = strrchr(master_url, '/');
     size_t base_len = 0;
 
     if (!p) p = strrchr(master_url, '\\');
 

     if (p) {

         base_len = p - master_url;

         if (av_strncasecmp(master_url, media_url, base_len)) {
             av_log(NULL, AV_LOG_WARNING, "Unable to find relative url\n");

             return NULL;

         }

     } else {
         return media_url;

     }

     return media_url + base_len + 1;

 }
 

 static int64_t get_stream_bit_rate(AVStream *stream)
 {

     AVCPBProperties *props = (AVCPBProperties*)av_stream_get_side_data(
         stream,
         AV_PKT_DATA_CPB_PROPERTIES,
         NULL
     );
 
     if (stream->codecpar->bit_rate)
         return stream->codecpar->bit_rate;
     else if (props)
         return props->max_bitrate;
 
     return 0;
 }
 

 static int create_master_playlist(AVFormatContext *s,
                                   VariantStream * const input_vs)
 {
     HLSContext *hls = s->priv_data;

     VariantStream *vs, *temp_vs;

     AVStream *vid_st, *aud_st;
     AVDictionary *options = NULL;
     unsigned int i, j;

     int ret, bandwidth;
     const char *m3u8_rel_name = NULL;

     const char *vtt_m3u8_rel_name = NULL;

     const char *ccgroup;
     const char *sgroup = NULL;

     ClosedCaptionsStream *ccs;

     const char *proto = avio_find_protocol_name(hls->master_m3u8_url);
     int is_file_proto = proto && !strcmp(proto, "file");
     int use_temp_file = is_file_proto && ((hls->flags & HLS_TEMP_FILE) || hls->master_publish_rate);

     char temp_filename[MAX_URL_SIZE];

 
     input_vs->m3u8_created = 1;
     if (!hls->master_m3u8_created) {
         /* For the first time, wait until all the media playlists are created */
         for (i = 0; i < hls->nb_varstreams; i++)
             if (!hls->var_streams[i].m3u8_created)
                 return 0;
     } else {
          /* Keep publishing the master playlist at the configured rate */
         if (&hls->var_streams[0] != input_vs || !hls->master_publish_rate ||
             input_vs->number % hls->master_publish_rate)
             return 0;
     }
 

     set_http_options(s, &options, hls);

     snprintf(temp_filename, sizeof(temp_filename), use_temp_file ? "%s.tmp" : "%s", hls->master_m3u8_url);
     ret = hlsenc_io_open(s, &hls->m3u8_out, temp_filename, &options);

     av_dict_free(&options);
     if (ret < 0) {

         av_log(s, AV_LOG_ERROR, "Failed to open master play list file '%s'\n",

                 temp_filename);

         goto fail;
     }
 

     ff_hls_write_playlist_version(hls->m3u8_out, hls->version);

     for (i = 0; i < hls->nb_ccstreams; i++) {
         ccs = &(hls->cc_streams[i]);
         avio_printf(hls->m3u8_out, "#EXT-X-MEDIA:TYPE=CLOSED-CAPTIONS");
         avio_printf(hls->m3u8_out, ",GROUP-ID=\"%s\"", ccs->ccgroup);
         avio_printf(hls->m3u8_out, ",NAME=\"%s\"", ccs->instreamid);
         if (ccs->language)
             avio_printf(hls->m3u8_out, ",LANGUAGE=\"%s\"", ccs->language);
         avio_printf(hls->m3u8_out, ",INSTREAM-ID=\"%s\"\n", ccs->instreamid);
     }
 

     /* For audio only variant streams add #EXT-X-MEDIA tag with attributes*/
     for (i = 0; i < hls->nb_varstreams; i++) {
         vs = &(hls->var_streams[i]);
 
         if (vs->has_video || vs->has_subtitle || !vs->agroup)
             continue;
 

         m3u8_rel_name = get_relative_url(hls->master_m3u8_url, vs->m3u8_name);

         if (!m3u8_rel_name) {
             av_log(s, AV_LOG_ERROR, "Unable to find relative URL\n");
             goto fail;
         }
 

         ff_hls_write_audio_rendition(hls->m3u8_out, vs->agroup, m3u8_rel_name, vs->language, i, hls->has_default_key ? vs->is_default : 1);

     }
 

     /* For variant streams with video add #EXT-X-STREAM-INF tag with attributes*/
     for (i = 0; i < hls->nb_varstreams; i++) {
         vs = &(hls->var_streams[i]);
 

         m3u8_rel_name = get_relative_url(hls->master_m3u8_url, vs->m3u8_name);

         if (!m3u8_rel_name) {

             av_log(s, AV_LOG_ERROR, "Unable to find relative URL\n");

             goto fail;
         }
 
         vid_st = NULL;
         aud_st = NULL;
         for (j = 0; j < vs->nb_streams; j++) {
             if (vs->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)
                 vid_st = vs->streams[j];
             else if (vs->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
                 aud_st = vs->streams[j];
         }
 
         if (!vid_st && !aud_st) {

             av_log(s, AV_LOG_WARNING, "Media stream not found\n");

             continue;
         }
 

         /**
          * Traverse through the list of audio only rendition streams and find
          * the rendition which has highest bitrate in the same audio group
          */
         if (vs->agroup) {
             for (j = 0; j < hls->nb_varstreams; j++) {
                 temp_vs = &(hls->var_streams[j]);
                 if (!temp_vs->has_video && !temp_vs->has_subtitle &&
                     temp_vs->agroup &&
                     !av_strcasecmp(temp_vs->agroup, vs->agroup)) {
                     if (!aud_st)
                         aud_st = temp_vs->streams[0];
                     if (temp_vs->streams[0]->codecpar->bit_rate >
                             aud_st->codecpar->bit_rate)
                         aud_st = temp_vs->streams[0];
                 }
             }
         }
 

         bandwidth = 0;
         if (vid_st)

             bandwidth += get_stream_bit_rate(vid_st);

         if (aud_st)

             bandwidth += get_stream_bit_rate(aud_st);

         bandwidth += bandwidth / 10;
 

         ccgroup = NULL;
         if (vid_st && vs->ccgroup) {
             /* check if this group name is available in the cc map string */
             for (j = 0; j < hls->nb_ccstreams; j++) {
                 ccs = &(hls->cc_streams[j]);
                 if (!av_strcasecmp(ccs->ccgroup, vs->ccgroup)) {
                     ccgroup = vs->ccgroup;
                     break;
                 }
             }
             if (j == hls->nb_ccstreams)

                 av_log(s, AV_LOG_WARNING, "mapping ccgroup %s not found\n",

                         vs->ccgroup);
         }
 

         if (vid_st && vs->sgroup) {
             sgroup = vs->sgroup;
             vtt_m3u8_rel_name = get_relative_url(hls->master_m3u8_url, vs->vtt_m3u8_name);
             if (!vtt_m3u8_rel_name) {
                 av_log(s, AV_LOG_WARNING, "Unable to find relative subtitle URL\n");
                 break;
             }
 
             ff_hls_write_subtitle_rendition(hls->m3u8_out, sgroup, vtt_m3u8_rel_name, vs->language, i, hls->has_default_key ? vs->is_default : 1);
         }
 

         if (!hls->has_default_key || !hls->has_video_m3u8) {
             ff_hls_write_stream_info(vid_st, hls->m3u8_out, bandwidth, m3u8_rel_name,

                     aud_st ? vs->agroup : NULL, vs->codec_attr, ccgroup, sgroup);

         } else {
             if (vid_st) {
                 ff_hls_write_stream_info(vid_st, hls->m3u8_out, bandwidth, m3u8_rel_name,

                                          aud_st ? vs->agroup : NULL, vs->codec_attr, ccgroup, sgroup);

             }
         }

     }
 fail:

     if (ret >=0)

         hls->master_m3u8_created = 1;

     hlsenc_io_close(s, &hls->m3u8_out, temp_filename);
     if (use_temp_file)
         ff_rename(temp_filename, hls->master_m3u8_url, s);
 

     return ret;
 }
 

 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 = 3;

     if (byterange_mode) {

         hls->version = 4;

         sequence = 0;
     }

     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);

     if ((ret = hlsenc_io_open(s, byterange_mode ? &hls->m3u8_out : &vs->out, temp_filename, &options)) < 0) {

         if (hls->ignore_io_errors)
             ret = 0;

         goto fail;

     }

     for (en = vs->segments; en; en = en->next) {

         if (target_duration <= en->duration)

             target_duration = lrint(en->duration);

     }
 

     vs->discontinuity_set = 0;

     ff_hls_write_playlist_header(byterange_mode ? hls->m3u8_out : vs->out, hls->version, hls->allowcache,

                                  target_duration, sequence, hls->pl_type, hls->flags & HLS_I_FRAMES_ONLY);

     if ((hls->flags & HLS_DISCONT_START) && sequence==hls->start_sequence && vs->discontinuity_set==0) {

         avio_printf(byterange_mode ? hls->m3u8_out : vs->out, "#EXT-X-DISCONTINUITY\n");

         vs->discontinuity_set = 1;

     }

     if (vs->has_video && (hls->flags & HLS_INDEPENDENT_SEGMENTS)) {

         avio_printf(byterange_mode ? hls->m3u8_out : vs->out, "#EXT-X-INDEPENDENT-SEGMENTS\n");

     }

     for (en = vs->segments; en; en = en->next) {

         if ((hls->encrypt || hls->key_info_file) && (!key_uri || strcmp(en->key_uri, key_uri) ||

                                     av_strcasecmp(en->iv_string, iv_string))) {

             avio_printf(byterange_mode ? hls->m3u8_out : vs->out, "#EXT-X-KEY:METHOD=AES-128,URI=\"%s\"", en->key_uri);

             if (*en->iv_string)

                 avio_printf(byterange_mode ? hls->m3u8_out : vs->out, ",IV=0x%s", en->iv_string);
             avio_printf(byterange_mode ? hls->m3u8_out : vs->out, "\n");

             key_uri = en->key_uri;
             iv_string = en->iv_string;
         }
 

         if ((hls->segment_type == SEGMENT_TYPE_FMP4) && (en == vs->segments)) {

             ff_hls_write_init_file(byterange_mode ? hls->m3u8_out : vs->out, (hls->flags & HLS_SINGLE_FILE) ? en->filename : vs->fmp4_init_filename,

                                    hls->flags & HLS_SINGLE_FILE, vs->init_range_length, 0);

         }

         ret = ff_hls_write_file_entry(byterange_mode ? hls->m3u8_out : vs->out, en->discont, byterange_mode,

                                       en->duration, hls->flags & HLS_ROUND_DURATIONS,

                                       en->size, en->pos, hls->baseurl,

                                       en->filename, prog_date_time_p, en->keyframe_size, en->keyframe_pos, hls->flags & HLS_I_FRAMES_ONLY);

         if (ret < 0) {
             av_log(s, AV_LOG_WARNING, "ff_hls_write_file_entry get error\n");
         }

     }
 

     if (last && (hls->flags & HLS_OMIT_ENDLIST)==0)

         ff_hls_write_end_list(byterange_mode ? hls->m3u8_out : vs->out);

     if (vs->vtt_m3u8_name) {
         snprintf(temp_vtt_filename, sizeof(temp_vtt_filename), use_temp_file ? "%s.tmp" : "%s", vs->vtt_m3u8_name);
         if ((ret = hlsenc_io_open(s, &hls->sub_m3u8_out, temp_vtt_filename, &options)) < 0) {

             if (hls->ignore_io_errors)
                 ret = 0;

             goto fail;

         }

         ff_hls_write_playlist_header(hls->sub_m3u8_out, hls->version, hls->allowcache,

                                      target_duration, sequence, PLAYLIST_TYPE_NONE, 0);

         for (en = vs->segments; en; en = en->next) {

             ret = ff_hls_write_file_entry(hls->sub_m3u8_out, 0, byterange_mode,
                                           en->duration, 0, en->size, en->pos,

                                           hls->baseurl, en->sub_filename, NULL, 0, 0, 0);

             if (ret < 0) {
                 av_log(s, AV_LOG_WARNING, "ff_hls_write_file_entry get error\n");
             }

         }
 
         if (last)

             ff_hls_write_end_list(hls->sub_m3u8_out);

 
     }
 

 fail:

     av_dict_free(&options);

     ret = hlsenc_io_close(s, byterange_mode ? &hls->m3u8_out : &vs->out, temp_filename);

     if (ret < 0) {
         return ret;
     }

     hlsenc_io_close(s, &hls->sub_m3u8_out, vs->vtt_m3u8_name);

     if (use_temp_file) {

         ff_rename(temp_filename, vs->m3u8_name, s);

         if (vs->vtt_m3u8_name)
             ff_rename(temp_vtt_filename, vs->vtt_m3u8_name, s);
     }

     if (ret >= 0 && hls->master_pl_name)
         if (create_master_playlist(s, vs) < 0)
             av_log(s, AV_LOG_WARNING, "Master playlist creation failed\n");
 

     return ret;
 }
 

 static int hls_start(AVFormatContext *s, VariantStream *vs)

 {
     HLSContext *c = s->priv_data;

     AVFormatContext *oc = vs->avf;
     AVFormatContext *vtt_oc = vs->vtt_avf;

     AVDictionary *options = NULL;

     const char *proto = NULL;
     int use_temp_file = 0;

     char iv_string[KEYSIZE*2 + 1];

     int err = 0;
 

     if (c->flags & HLS_SINGLE_FILE) {

         char *new_name = av_strdup(vs->basename);
         if (!new_name)
             return AVERROR(ENOMEM);
         ff_format_set_url(oc, new_name);
         if (vs->vtt_basename) {
             new_name = av_strdup(vs->vtt_basename);
             if (!new_name)
                 return AVERROR(ENOMEM);
             ff_format_set_url(vtt_oc, new_name);
         }

     } else if (c->max_seg_size > 0) {

         char *filename = NULL;
         if (replace_int_data_in_filename(&filename,

 #if FF_API_HLS_WRAP

             vs->basename, 'd', c->wrap ? vs->sequence % c->wrap : vs->sequence) < 1) {

 #else

             vs->basename, 'd', vs->sequence) < 1) {

 #endif

                 av_freep(&filename);

                 av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s', you can try to use -strftime 1 with it\n", vs->basename);

                 return AVERROR(EINVAL);
         }

         ff_format_set_url(oc, filename);

     } else {

         if (c->use_localtime) {
             time_t now0;
             struct tm *tm, tmpbuf;

             int bufsize = strlen(vs->basename) + MAX_URL_SIZE;

             char *buf = av_mallocz(bufsize);
             if (!buf)
                 return AVERROR(ENOMEM);

             time(&now0);
             tm = localtime_r(&now0, &tmpbuf);

             ff_format_set_url(oc, buf);
             if (!strftime(oc->url, bufsize, vs->basename, tm)) {

                 av_log(oc, AV_LOG_ERROR, "Could not get segment filename with strftime\n");

                 return AVERROR(EINVAL);
             }

             err = sls_flag_use_localtime_filename(oc, c, vs);

             if (err < 0) {
                 return AVERROR(ENOMEM);

             }

             if (c->use_localtime_mkdir) {
                 const char *dir;

                 char *fn_copy = av_strdup(oc->url);

                 if (!fn_copy)
                     return AVERROR(ENOMEM);

                 dir = av_dirname(fn_copy);

                 if (ff_mkdir_p(dir) == -1 && errno != EEXIST) {

                     av_log(oc, AV_LOG_ERROR, "Could not create directory %s with use_localtime_mkdir\n", dir);

                     av_freep(&fn_copy);

                     return AVERROR(errno);
                 }

                 av_freep(&fn_copy);

             }

         } else {
             char *filename = NULL;
             if (replace_int_data_in_filename(&filename,

 #if FF_API_HLS_WRAP

                    vs->basename, 'd', c->wrap ? vs->sequence % c->wrap : vs->sequence) < 1) {

 #else

                    vs->basename, 'd', vs->sequence) < 1) {

 #endif

                 av_freep(&filename);

                 av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s' you can try to use -strftime 1 with it\n", vs->basename);

                 return AVERROR(EINVAL);
             }

             ff_format_set_url(oc, filename);

         }

         if (vs->vtt_basename) {

             char *filename = NULL;
             if (replace_int_data_in_filename(&filename,

 #if FF_API_HLS_WRAP

                 vs->vtt_basename, 'd', c->wrap ? vs->sequence % c->wrap : vs->sequence) < 1) {

 #else

                 vs->vtt_basename, 'd', vs->sequence) < 1) {

 #endif

                 av_freep(&filename);

                 av_log(vtt_oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", vs->vtt_basename);

                 return AVERROR(EINVAL);
             }

             ff_format_set_url(vtt_oc, filename);

        }
     }

     proto = avio_find_protocol_name(oc->url);
     use_temp_file = proto && !strcmp(proto, "file") && (c->flags & HLS_TEMP_FILE);
 

     if (use_temp_file) {

         char *new_name = av_asprintf("%s.tmp", oc->url);
         if (!new_name)
             return AVERROR(ENOMEM);
         ff_format_set_url(oc, new_name);

     }
 

     if (c->key_info_file || c->encrypt) {

         if (c->segment_type == SEGMENT_TYPE_FMP4) {
             av_log(s, AV_LOG_ERROR, "Encrypted fmp4 not yet supported\n");
             return AVERROR_PATCHWELCOME;
         }
 

         if (c->key_info_file && c->encrypt) {
             av_log(s, AV_LOG_WARNING, "Cannot use both -hls_key_info_file and -hls_enc,"

                   " ignoring -hls_enc\n");

         }

         if (!vs->encrypt_started || (c->flags & HLS_PERIODIC_REKEY)) {

             if (c->key_info_file) {

                 if ((err = hls_encryption_start(s, vs)) < 0)

                     goto fail;
             } else {

                 if (!c->encrypt_started) {
                     if ((err = do_encrypt(s, vs)) < 0)
                         goto fail;
                     c->encrypt_started = 1;
                 }
                 av_strlcpy(vs->key_uri, c->key_uri, sizeof(vs->key_uri));
                 av_strlcpy(vs->key_string, c->key_string, sizeof(vs->key_string));
                 av_strlcpy(vs->iv_string, c->iv_string, sizeof(vs->iv_string));

             }

             vs->encrypt_started = 1;

         }

         err = av_strlcpy(iv_string, vs->iv_string, sizeof(iv_string));

         if (!err) {

             snprintf(iv_string, sizeof(iv_string), "%032"PRIx64, vs->sequence);

             memset(vs->iv_string, 0, sizeof(vs->iv_string));
             memcpy(vs->iv_string, iv_string, sizeof(iv_string));

         }

     }
     if (c->segment_type != SEGMENT_TYPE_FMP4) {

         if (oc->oformat->priv_class && oc->priv_data) {
             av_opt_set(oc->priv_data, "mpegts_flags", "resend_headers", 0);
         }

         if (c->flags & HLS_SINGLE_FILE) {

             set_http_options(s, &options, c);

             if ((err = hlsenc_io_open(s, &vs->out, oc->url, &options)) < 0) {
                 if (c->ignore_io_errors)
                     err = 0;
                 goto fail;
             }
         }
     }
     if (vs->vtt_basename) {
         set_http_options(s, &options, c);
         if ((err = hlsenc_io_open(s, &vtt_oc->pb, vtt_oc->url, &options)) < 0) {
             if (c->ignore_io_errors)
                 err = 0;
             goto fail;
         }

     }

     av_dict_free(&options);

     if (vs->vtt_basename) {

         err = avformat_write_header(vtt_oc,NULL);
         if (err < 0)
             return err;
     }

     return 0;

 fail:
     av_dict_free(&options);
 
     return err;

 }
 

 static const char * get_default_pattern_localtime_fmt(AVFormatContext *s)

 {
     char b[21];
     time_t t = time(NULL);
     struct tm *p, tmbuf;

     HLSContext *hls = s->priv_data;
 

     p = localtime_r(&t, &tmbuf);
     // no %s support when strftime returned error or left format string unchanged

     // also no %s support on MSVC, which invokes the invalid parameter handler on unsupported format strings, instead of returning an error

     if (hls->segment_type == SEGMENT_TYPE_FMP4) {
         return (HAVE_LIBC_MSVCRT || !strftime(b, sizeof(b), "%s", p) || !strcmp(b, "%s")) ? "-%Y%m%d%H%M%S.m4s" : "-%s.m4s";
     }

     return (HAVE_LIBC_MSVCRT || !strftime(b, sizeof(b), "%s", p) || !strcmp(b, "%s")) ? "-%Y%m%d%H%M%S.ts" : "-%s.ts";

 }
 

 static int append_postfix(char *name, int name_buf_len, int i)

 {
     char *p;
     char extension[10] = {'\0'};
 
     p = strrchr(name, '.');
     if (p) {
         av_strlcpy(extension, p, sizeof(extension));
         *p = '\0';
     }
 
     snprintf(name + strlen(name), name_buf_len - strlen(name), POSTFIX_PATTERN, i);
 
     if (strlen(extension))
         av_strlcat(name, extension, name_buf_len);
 
     return 0;
 }
 

 static int validate_name(int nb_vs, const char *fn)
 {

     const char *filename, *subdir_name;
     char *fn_dup = NULL;

     int ret = 0;
 

     if (!fn)
         return AVERROR(EINVAL);

     fn_dup = av_strdup(fn);

     if (!fn_dup)
         return AVERROR(ENOMEM);

     filename = av_basename(fn);

     subdir_name = av_dirname(fn_dup);

     if (nb_vs > 1 && !av_stristr(filename, "%v") && !av_stristr(subdir_name, "%v")) {

         av_log(NULL, AV_LOG_ERROR, "More than 1 variant streams are present, %%v is expected "
                "either in the filename or in the sub-directory name of file %s\n", fn);

         ret = AVERROR(EINVAL);
         goto fail;
     }
 

     if (av_stristr(filename, "%v") && av_stristr(subdir_name, "%v")) {

         av_log(NULL, AV_LOG_ERROR, "%%v is expected either in the filename or "
                "in the sub-directory name of file %s, but only in one of them\n", fn);

         ret = AVERROR(EINVAL);
         goto fail;
     }
 

 fail:

     av_freep(&fn_dup);

     return ret;
 }
 

 static int format_name(const char *buf, char **s, int index, const char *varname)

 {

     const char *proto, *dir;

     char *orig_buf_dup = NULL, *mod_buf_dup = NULL;

     int ret = 0;
 
     orig_buf_dup = av_strdup(buf);

     if (!orig_buf_dup)
         return AVERROR(ENOMEM);

     if (!av_stristr(buf, "%v")) {
         *s = orig_buf_dup;

         return 0;

     }
 

     if (!varname) {
         if (replace_int_data_in_filename(s, orig_buf_dup, 'v', index) < 1) {
             ret = AVERROR(EINVAL);
             goto fail;
         }
     } else {
         if (replace_str_data_in_filename(s, orig_buf_dup, 'v', varname) < 1) {
             ret = AVERROR(EINVAL);
             goto fail;
         }

     }
 

     proto = avio_find_protocol_name(orig_buf_dup);
     dir = av_dirname(orig_buf_dup);
 
     /* if %v is present in the file's directory, create sub-directory */
     if (av_stristr(dir, "%v") && proto && !strcmp(proto, "file")) {

         mod_buf_dup = av_strdup(*s);

         dir = av_dirname(mod_buf_dup);

         if (ff_mkdir_p(dir) == -1 && errno != EEXIST) {

             ret = AVERROR(errno);
             goto fail;
         }
     }
 

 fail:
     av_freep(&orig_buf_dup);

     av_freep(&mod_buf_dup);

     return ret;
 }
 

 static int get_nth_codec_stream_index(AVFormatContext *s,
                                       enum AVMediaType codec_type,

                                       int64_t stream_id)

 {
     unsigned int stream_index, cnt;
     if (stream_id < 0 || stream_id > s->nb_streams - 1)
         return -1;
     cnt = 0;
     for (stream_index = 0; stream_index < s->nb_streams; stream_index++) {
         if (s->streams[stream_index]->codecpar->codec_type != codec_type)
             continue;
         if (cnt == stream_id)
             return stream_index;
         cnt++;
     }
     return -1;
 }
 
 static int parse_variant_stream_mapstring(AVFormatContext *s)
 {
     HLSContext *hls = s->priv_data;
     VariantStream *vs;

     int stream_index, i, j;

     enum AVMediaType codec_type;

     int nb_varstreams = 0, nb_streams;

     char *p, *q, *saveptr1, *saveptr2, *varstr, *keyval;
     const char *val;
 
     /**
      * Expected format for var_stream_map string is as below:
      * "a:0,v:0 a:1,v:1"

      * "a:0,agroup:a0,default:1,language:ENG a:1,agroup:a1,default:0 v:0,agroup:a0  v:1,agroup:a1"

      * This string specifies how to group the audio, video and subtitle streams
      * into different variant streams. The variant stream groups are separated
      * by space.
      *
      * a:, v:, s: are keys to specify audio, video and subtitle streams
      * respectively. Allowed values are 0 to 9 digits (limited just based on
      * practical usage)
      *

      * agroup: is key to specify audio group. A string can be given as value.

      * sgroup: is key to specify subtitle group. A string can be given as value.

      */
     p = av_strdup(hls->var_stream_map);

     if (!p)
         return AVERROR(ENOMEM);
 

     q = p;

     while (av_strtok(q, " \t", &saveptr1)) {

         q = NULL;

         nb_varstreams++;

     }
     av_freep(&p);
 

     hls->var_streams = av_mallocz(sizeof(*hls->var_streams) * nb_varstreams);

     if (!hls->var_streams)
         return AVERROR(ENOMEM);

     hls->nb_varstreams = nb_varstreams;

 
     p = hls->var_stream_map;
     nb_varstreams = 0;
     while (varstr = av_strtok(p, " \t", &saveptr1)) {
         p = NULL;
 

         if (nb_varstreams < hls->nb_varstreams) {
             vs = &(hls->var_streams[nb_varstreams]);
             vs->var_stream_idx = nb_varstreams;

             vs->is_default = 0;

             nb_varstreams++;
         } else

             return AVERROR(EINVAL);
 
         q = varstr;

         while (1) {

             if (!av_strncasecmp(q, "a:", 2) || !av_strncasecmp(q, "v:", 2) ||
                 !av_strncasecmp(q, "s:", 2))
                 vs->nb_streams++;

             q = strchr(q, ',');
             if (!q)
                 break;

             q++;
         }
         vs->streams = av_mallocz(sizeof(AVStream *) * vs->nb_streams);
         if (!vs->streams)
             return AVERROR(ENOMEM);
 
         nb_streams = 0;
         while (keyval = av_strtok(varstr, ",", &saveptr2)) {

             int64_t num;
             char *end;

             varstr = NULL;

             if (av_strstart(keyval, "language:", &val)) {

                 vs->language = val;

                 continue;
             } else if (av_strstart(keyval, "default:", &val)) {

                 vs->is_default = (!av_strncasecmp(val, "YES", strlen("YES")) ||
                                   (!av_strncasecmp(val, "1", strlen("1"))));
                 hls->has_default_key = 1;
                 continue;

             } else if (av_strstart(keyval, "name:", &val)) {

                 vs->varname  = val;

                 continue;

             } else if (av_strstart(keyval, "agroup:", &val)) {

                 vs->agroup   = val;

                 continue;

             } else if (av_strstart(keyval, "sgroup:", &val)) {

                 vs->sgroup   = val;

                 continue;

             } else if (av_strstart(keyval, "ccgroup:", &val)) {

                 vs->ccgroup  = val;

                 continue;

             } else if (av_strstart(keyval, "v:", &val)) {

                 codec_type = AVMEDIA_TYPE_VIDEO;

                 hls->has_video_m3u8 = 1;

             } else if (av_strstart(keyval, "a:", &val)) {
                 codec_type = AVMEDIA_TYPE_AUDIO;
             } else if (av_strstart(keyval, "s:", &val)) {
                 codec_type = AVMEDIA_TYPE_SUBTITLE;
             } else {
                 av_log(s, AV_LOG_ERROR, "Invalid keyval %s\n", keyval);
                 return AVERROR(EINVAL);
             }
 

             num = strtoll(val, &end, 0);
             if (!av_isdigit(*val) || *end != '\0') {
                 av_log(s, AV_LOG_ERROR, "Invalid stream number: '%s'\n", val);
                 return AVERROR(EINVAL);
             }
             stream_index = get_nth_codec_stream_index(s, codec_type, num);

 
             if (stream_index >= 0 && nb_streams < vs->nb_streams) {

                 for (i = 0; nb_streams > 0 && i < nb_streams; i++) {

                     if (vs->streams[i] == s->streams[stream_index]) {
                         av_log(s, AV_LOG_ERROR, "Same elementary stream found more than once inside "
                                "variant definition #%d\n", nb_varstreams - 1);
                         return AVERROR(EINVAL);
                     }
                 }

                 for (j = 0; nb_varstreams > 1 && j < nb_varstreams - 1; j++) {
                     for (i = 0; i < hls->var_streams[j].nb_streams; i++) {

                         if (hls->var_streams[j].streams[i] == s->streams[stream_index]) {
                             av_log(s, AV_LOG_ERROR, "Same elementary stream found more than once "
                                    "in two different variant definitions #%d and #%d\n",
                                    j, nb_varstreams - 1);
                             return AVERROR(EINVAL);
                         }
                     }
                 }

                 vs->streams[nb_streams++] = s->streams[stream_index];
             } else {
                 av_log(s, AV_LOG_ERROR, "Unable to map stream at %s\n", keyval);
                 return AVERROR(EINVAL);
             }
         }
     }
     av_log(s, AV_LOG_DEBUG, "Number of variant streams %d\n",
             hls->nb_varstreams);
 
     return 0;
 }
 

 static int parse_cc_stream_mapstring(AVFormatContext *s)
 {
     HLSContext *hls = s->priv_data;

     int nb_ccstreams = 0;

     char *p, *q, *ccstr, *keyval;
     char *saveptr1 = NULL, *saveptr2 = NULL;

     const char *val;
     ClosedCaptionsStream *ccs;
 
     p = av_strdup(hls->cc_stream_map);

     if(!p)
         return AVERROR(ENOMEM);
 

     q = p;

     while (av_strtok(q, " \t", &saveptr1)) {

         q = NULL;

         nb_ccstreams++;

     }
     av_freep(&p);
 

     hls->cc_streams = av_mallocz(sizeof(*hls->cc_streams) * nb_ccstreams);

     if (!hls->cc_streams)
         return AVERROR(ENOMEM);

     hls->nb_ccstreams = nb_ccstreams;

 
     p = hls->cc_stream_map;
     nb_ccstreams = 0;
     while (ccstr = av_strtok(p, " \t", &saveptr1)) {
         p = NULL;
 
         if (nb_ccstreams < hls->nb_ccstreams)
             ccs = &(hls->cc_streams[nb_ccstreams++]);
         else
             return AVERROR(EINVAL);
 
         while (keyval = av_strtok(ccstr, ",", &saveptr2)) {
             ccstr = NULL;
 
             if (av_strstart(keyval, "ccgroup:", &val)) {

                 ccs->ccgroup    = val;

             } else if (av_strstart(keyval, "instreamid:", &val)) {

                 ccs->instreamid = val;

             } else if (av_strstart(keyval, "language:", &val)) {

                 ccs->language   = val;

             } else {
                 av_log(s, AV_LOG_ERROR, "Invalid keyval %s\n", keyval);
                 return AVERROR(EINVAL);
             }
         }
 
         if (!ccs->ccgroup || !ccs->instreamid) {
             av_log(s, AV_LOG_ERROR, "Insufficient parameters in cc stream map string\n");
             return AVERROR(EINVAL);
         }
 
         if (av_strstart(ccs->instreamid, "CC", &val)) {

             if (atoi(val) < 1 || atoi(val) > 4) {

                 av_log(s, AV_LOG_ERROR, "Invalid instream ID CC index %d in %s, range 1-4\n",
                        atoi(val), ccs->instreamid);
                 return AVERROR(EINVAL);
             }
         } else if (av_strstart(ccs->instreamid, "SERVICE", &val)) {

             if (atoi(val) < 1 || atoi(val) > 63) {

                 av_log(s, AV_LOG_ERROR, "Invalid instream ID SERVICE index %d in %s, range 1-63 \n",
                        atoi(val), ccs->instreamid);
                 return AVERROR(EINVAL);
             }
         } else {

             av_log(s, AV_LOG_ERROR, "Invalid instream ID %s, supported are CCn or SERVICEn\n",

                    ccs->instreamid);
             return AVERROR(EINVAL);
         }
     }
 
     return 0;
 }
 

 static int update_variant_stream_info(AVFormatContext *s)
 {

     HLSContext *hls = s->priv_data;
     unsigned int i;

     int ret = 0;
 
     if (hls->cc_stream_map) {
         ret = parse_cc_stream_mapstring(s);
         if (ret < 0)
             return ret;
     }

 
     if (hls->var_stream_map) {
         return parse_variant_stream_mapstring(s);
     } else {
         //By default, a single variant stream with all the codec streams is created

         hls->var_streams = av_mallocz(sizeof(*hls->var_streams));

         if (!hls->var_streams)
             return AVERROR(ENOMEM);

         hls->nb_varstreams = 1;

         hls->var_streams[0].var_stream_idx = 0;

         hls->var_streams[0].nb_streams = s->nb_streams;
         hls->var_streams[0].streams = av_mallocz(sizeof(AVStream *) *
                                             hls->var_streams[0].nb_streams);

         if (!hls->var_streams[0].streams)

             return AVERROR(ENOMEM);
 

         //by default, the first available ccgroup is mapped to the variant stream

         if (hls->nb_ccstreams)

             hls->var_streams[0].ccgroup = hls->cc_streams[0].ccgroup;

         for (i = 0; i < s->nb_streams; i++)
             hls->var_streams[0].streams[i] = s->streams[i];
     }
     return 0;
 }
 

 static int update_master_pl_info(AVFormatContext *s)
 {

     HLSContext *hls = s->priv_data;

     const char *dir;

     char *fn1= NULL, *fn2 = NULL;

     int ret = 0;

     fn1 = av_strdup(s->url);

     if (!fn1)
         return AVERROR(ENOMEM);

     dir = av_dirname(fn1);
 
     /**
      * if output file's directory has %v, variants are created in sub-directories
      * then master is created at the sub-directories level
      */
     if (dir && av_stristr(av_basename(dir), "%v")) {
         fn2 = av_strdup(dir);

         if (!fn2) {
             ret = AVERROR(ENOMEM);
             goto fail;
         }

         dir = av_dirname(fn2);
     }
 

     if (dir && strcmp(dir, "."))
         hls->master_m3u8_url = av_append_path_component(dir, hls->master_pl_name);
     else
         hls->master_m3u8_url = av_strdup(hls->master_pl_name);
 
     if (!hls->master_m3u8_url) {
         ret = AVERROR(ENOMEM);
         goto fail;

     }
 

 fail:

     av_freep(&fn1);
     av_freep(&fn2);
 

     return ret;

 }
 

 static int hls_write_header(AVFormatContext *s)
 {
     HLSContext *hls = s->priv_data;

     int ret, i, j;
     VariantStream *vs = NULL;

     for (i = 0; i < hls->nb_varstreams; i++) {
         vs = &hls->var_streams[i];
 

         ret = avformat_write_header(vs->avf, NULL);
         if (ret < 0)
             return ret;

         //av_assert0(s->nb_streams == hls->avf->nb_streams);
         for (j = 0; j < vs->nb_streams; j++) {
             AVStream *inner_st;
             AVStream *outer_st = vs->streams[j];
 
             if (hls->max_seg_size > 0) {
                 if ((outer_st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) &&
                     (outer_st->codecpar->bit_rate > hls->max_seg_size)) {
                     av_log(s, AV_LOG_WARNING, "Your video bitrate is bigger than hls_segment_size, "
                            "(%"PRId64 " > %"PRId64 "), the result maybe not be what you want.",
                            outer_st->codecpar->bit_rate, hls->max_seg_size);
                 }

             }
 

             if (outer_st->codecpar->codec_type != AVMEDIA_TYPE_SUBTITLE)
                 inner_st = vs->avf->streams[j];
             else if (vs->vtt_avf)
                 inner_st = vs->vtt_avf->streams[0];
             else {
                 /* We have a subtitle stream, when the user does not want one */
                 inner_st = NULL;
                 continue;
             }
             avpriv_set_pts_info(outer_st, inner_st->pts_wrap_bits, inner_st->time_base.num, inner_st->time_base.den);

             write_codec_attr(outer_st, vs);
 
         }
         /* Update the Codec Attr string for the mapped audio groups */
         if (vs->has_video && vs->agroup) {
             for (j = 0; j < hls->nb_varstreams; j++) {
                 VariantStream *vs_agroup = &(hls->var_streams[j]);
                 if (!vs_agroup->has_video && !vs_agroup->has_subtitle &&
                     vs_agroup->agroup &&
                     !av_strcasecmp(vs_agroup->agroup, vs->agroup)) {
                     write_codec_attr(vs_agroup->streams[0], vs);
                 }
             }

         }

     }

     return ret;
 }
 

 static int hls_init_file_resend(AVFormatContext *s, VariantStream *vs)
 {
     HLSContext *hls = s->priv_data;
     AVDictionary *options = NULL;
     int ret = 0;
 
     set_http_options(s, &options, hls);

     ret = hlsenc_io_open(s, &vs->out, vs->base_output_dirname, &options);

     av_dict_free(&options);
     if (ret < 0)
         return ret;
     avio_write(vs->out, vs->init_buffer, vs->init_range_length);
     hlsenc_io_close(s, &vs->out, hls->fmp4_init_filename);
 
     return ret;
 }
 

 static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
 {
     HLSContext *hls = s->priv_data;

     AVFormatContext *oc = NULL;

     AVStream *st = s->streams[pkt->stream_index];

     int64_t end_pts = 0;

     int is_ref_pkt = 1;

     int ret = 0, can_split = 1, i, j;

     int stream_index = 0;

     int range_length = 0;

     const char *proto = NULL;
     int use_temp_file = 0;

     VariantStream *vs = NULL;

     char *old_filename = NULL;

 
     for (i = 0; i < hls->nb_varstreams; i++) {
         vs = &hls->var_streams[i];
         for (j = 0; j < vs->nb_streams; j++) {
             if (vs->streams[j] == st) {

                 if (st->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE) {

                     oc = vs->vtt_avf;
                     stream_index = 0;
                 } else {
                     oc = vs->avf;
                     stream_index = j;
                 }
                 break;
             }
         }
 
         if (oc)
             break;
     }
 
     if (!oc) {
         av_log(s, AV_LOG_ERROR, "Unable to find mapping variant stream\n");
         return AVERROR(ENOMEM);
     }
 
     end_pts = hls->recording_time * vs->number;

     if (vs->sequence - vs->nb_entries > hls->start_sequence && hls->init_time > 0) {

         /* reset end_pts, hls->recording_time at end of the init hls list */

         int64_t init_list_dur = hls->init_time * vs->nb_entries * AV_TIME_BASE;

         int64_t after_init_list_dur = (vs->sequence - hls->start_sequence - vs->nb_entries) * (hls->time * AV_TIME_BASE);

         hls->recording_time = hls->time * AV_TIME_BASE;
         end_pts = init_list_dur + after_init_list_dur ;
     }
 

     if (vs->start_pts == AV_NOPTS_VALUE) {
         vs->start_pts = pkt->pts;

         if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO)
             vs->start_pts_from_audio = 1;
     }
     if (vs->start_pts_from_audio && st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO && vs->start_pts > pkt->pts) {
         vs->start_pts = pkt->pts;
         vs->start_pts_from_audio = 0;

     }
 

     if (vs->has_video) {

         can_split = st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO &&

                     ((pkt->flags & AV_PKT_FLAG_KEY) || (hls->flags & HLS_SPLIT_BY_TIME));

         is_ref_pkt = (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) && (pkt->stream_index == vs->reference_stream_index);

     }

     if (pkt->pts == AV_NOPTS_VALUE)
         is_ref_pkt = can_split = 0;

     if (is_ref_pkt) {

         if (vs->end_pts == AV_NOPTS_VALUE)
             vs->end_pts = pkt->pts;

         if (vs->new_start) {
             vs->new_start = 0;
             vs->duration = (double)(pkt->pts - vs->end_pts)

                                        * st->time_base.num / st->time_base.den;

             vs->dpp = (double)(pkt->duration) * st->time_base.num / st->time_base.den;

         } else {

             if (pkt->duration) {

                 vs->duration += (double)(pkt->duration) * st->time_base.num / st->time_base.den;

             } else {
                 av_log(s, AV_LOG_WARNING, "pkt->duration = 0, maybe the hls segment duration will not precise\n");

                 vs->duration = (double)(pkt->pts - vs->end_pts) * st->time_base.num / st->time_base.den;

             }

         }

     }

 
     if (vs->packets_written && can_split && av_compare_ts(pkt->pts - vs->start_pts, st->time_base,

                                                           end_pts, AV_TIME_BASE_Q) >= 0) {

         int64_t new_start_pos;

         int byterange_mode = (hls->flags & HLS_SINGLE_FILE) || (hls->max_seg_size > 0);

         av_write_frame(oc, NULL); /* Flush any buffered data */
         new_start_pos = avio_tell(oc->pb);
         vs->size = new_start_pos - vs->start_pos;
         avio_flush(oc->pb);

         if (hls->segment_type == SEGMENT_TYPE_FMP4) {
             if (!vs->init_range_length) {

                 range_length = avio_close_dyn_buf(oc->pb, &vs->init_buffer);
                 if (range_length <= 0)
                     return AVERROR(EINVAL);
                 avio_write(vs->out, vs->init_buffer, range_length);
                 if (!hls->resend_init_file)
                     av_freep(&vs->init_buffer);

                 vs->init_range_length = range_length;
                 avio_open_dyn_buf(&oc->pb);
                 vs->packets_written = 0;
                 vs->start_pos = range_length;

                 if (!byterange_mode) {

                     hlsenc_io_close(s, &vs->out, vs->base_output_dirname);

                 }

             }

         }
         if (!byterange_mode) {

             if (vs->vtt_avf) {

                 hlsenc_io_close(s, &vs->vtt_avf->pb, vs->vtt_avf->url);

             }

         }

         if (hls->flags & HLS_SINGLE_FILE) {
             ret = flush_dynbuf(vs, &range_length);

             av_freep(&vs->temp_buffer);

             if (ret < 0) {
                 return ret;
             }
             vs->size = range_length;
         } else {

             if (oc->url[0]) {
                 proto = avio_find_protocol_name(oc->url);
                 use_temp_file = proto && !strcmp(proto, "file")
                                       && (hls->flags & HLS_TEMP_FILE);
             }
 

             if ((hls->max_seg_size > 0 && (vs->size >= hls->max_seg_size)) || !byterange_mode) {

                 AVDictionary *options = NULL;

                 char *filename = NULL;
                 if (hls->key_info_file || hls->encrypt) {

                     av_dict_set(&options, "encryption_key", vs->key_string, 0);
                     av_dict_set(&options, "encryption_iv", vs->iv_string, 0);

                     filename = av_asprintf("crypto:%s", oc->url);
                 } else {
                     filename = av_asprintf("%s", oc->url);

                 }

                 if (!filename) {

                     av_dict_free(&options);

                     return AVERROR(ENOMEM);
                 }

 
                 // look to rename the asset name
                 if (use_temp_file)
                     av_dict_set(&options, "mpegts_flags", "resend_headers", 0);
 
                 set_http_options(s, &options, hls);
 

                 ret = hlsenc_io_open(s, &vs->out, filename, &options);

                 if (ret < 0) {

                     av_log(s, hls->ignore_io_errors ? AV_LOG_WARNING : AV_LOG_ERROR,

                            "Failed to open file '%s'\n", filename);

                     av_freep(&filename);

                     av_dict_free(&options);

                     return hls->ignore_io_errors ? 0 : ret;

                 }

                 if (hls->segment_type == SEGMENT_TYPE_FMP4) {
                     write_styp(vs->out);
                 }

                 ret = flush_dynbuf(vs, &range_length);
                 if (ret < 0) {

                     av_freep(&filename);

                     av_dict_free(&options);

                     return ret;
                 }

                 ret = hlsenc_io_close(s, &vs->out, filename);
                 if (ret < 0) {
                     av_log(s, AV_LOG_WARNING, "upload segment failed,"
                            " will retry with a new http session.\n");
                     ff_format_io_close(s, &vs->out);
                     ret = hlsenc_io_open(s, &vs->out, filename, &options);
                     reflush_dynbuf(vs, &range_length);
                     ret = hlsenc_io_close(s, &vs->out, filename);
                 }

                 av_dict_free(&options);

                 av_freep(&vs->temp_buffer);
                 av_freep(&filename);

             }

             if (use_temp_file)
                 hls_rename_temp_file(s, oc);

         }
 

         old_filename = av_strdup(oc->url);

         if (!old_filename) {
             return AVERROR(ENOMEM);
         }
 

         if (vs->start_pos || hls->segment_type != SEGMENT_TYPE_FMP4) {

             double cur_duration =  (double)(pkt->pts - vs->end_pts) * st->time_base.num / st->time_base.den;
             ret = hls_append_segment(s, hls, vs, cur_duration, vs->start_pos, vs->size);

             vs->end_pts = pkt->pts;
             vs->duration = 0;
             if (ret < 0) {

                 av_freep(&old_filename);

                 return ret;
             }

         }

         // if we're building a VOD playlist, skip writing the manifest multiple times, and just wait until the end
         if (hls->pl_type != PLAYLIST_TYPE_VOD) {
             if ((ret = hls_window(s, 0, vs)) < 0) {

                 av_log(s, AV_LOG_WARNING, "upload playlist failed, will retry with a new http session.\n");
                 ff_format_io_close(s, &vs->out);
                 if ((ret = hls_window(s, 0, vs)) < 0) {

                     av_freep(&old_filename);

                     return ret;
                 }

             }
         }

         if (hls->resend_init_file && hls->segment_type == SEGMENT_TYPE_FMP4) {
             ret = hls_init_file_resend(s, vs);
             if (ret < 0) {
                 av_freep(&old_filename);
                 return ret;
             }
         }
 

         if (hls->flags & HLS_SINGLE_FILE) {

             vs->start_pos += vs->size;

         } else if (hls->max_seg_size > 0) {

             vs->start_pos = new_start_pos;
             if (vs->size >= hls->max_seg_size) {

                 vs->sequence++;
                 sls_flag_file_rename(hls, vs, old_filename);
                 ret = hls_start(s, vs);
                 vs->start_pos = 0;

                 /* When split segment by byte, the duration is short than hls_time,
                  * so it is not enough one segment duration as hls_time, */
             }

         } else {

             vs->start_pos = new_start_pos;

             sls_flag_file_rename(hls, vs, old_filename);
             ret = hls_start(s, vs);

         }

         vs->number++;

         av_freep(&old_filename);

         if (ret < 0) {

             return ret;

         }

 
     }
 

     vs->packets_written++;

     if (oc->pb) {

         ret = ff_write_chained(oc, stream_index, pkt, s, 0);

         vs->video_keyframe_size += pkt->size;

         if ((st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) && (pkt->flags & AV_PKT_FLAG_KEY)) {

             vs->video_keyframe_size = avio_tell(oc->pb);

         } else {

             vs->video_keyframe_pos = avio_tell(vs->out);

         }

         if (hls->ignore_io_errors)
             ret = 0;
     }

 
     return ret;
 }
 

 static void hls_deinit(AVFormatContext *s)

 {

     HLSContext *hls = s->priv_data;

     int i = 0;
     VariantStream *vs = NULL;
 
     for (i = 0; i < hls->nb_varstreams; i++) {
         vs = &hls->var_streams[i];
 
         av_freep(&vs->basename);
         av_freep(&vs->base_output_dirname);
         av_freep(&vs->fmp4_init_filename);

         av_freep(&vs->vtt_basename);
         av_freep(&vs->vtt_m3u8_name);

         avformat_free_context(vs->vtt_avf);

         avformat_free_context(vs->avf);

         if (hls->resend_init_file)
             av_freep(&vs->init_buffer);

         hls_free_segments(vs->segments);
         hls_free_segments(vs->old_segments);
         av_freep(&vs->m3u8_name);
         av_freep(&vs->streams);

     }
 
     ff_format_io_close(s, &hls->m3u8_out);
     ff_format_io_close(s, &hls->sub_m3u8_out);
     av_freep(&hls->key_basename);
     av_freep(&hls->var_streams);
     av_freep(&hls->cc_streams);
     av_freep(&hls->master_m3u8_url);

 }
 

 static int hls_write_trailer(struct AVFormatContext *s)
 {
     HLSContext *hls = s->priv_data;

     AVFormatContext *oc = NULL;
     AVFormatContext *vtt_oc = NULL;
     char *old_filename = NULL;

     const char *proto = NULL;
     int use_temp_file = 0;

     int i;

     int ret = 0;

     VariantStream *vs = NULL;

     AVDictionary *options = NULL;
     int range_length, byterange_mode;

 
     for (i = 0; i < hls->nb_varstreams; i++) {

         char *filename = NULL;

         vs = &hls->var_streams[i];

         oc = vs->avf;
         vtt_oc = vs->vtt_avf;

         old_filename = av_strdup(oc->url);

         use_temp_file = 0;

         if (!old_filename) {
             return AVERROR(ENOMEM);

         }

         if (hls->key_info_file || hls->encrypt) {

             av_dict_set(&options, "encryption_key", vs->key_string, 0);
             av_dict_set(&options, "encryption_iv", vs->iv_string, 0);

             filename = av_asprintf("crypto:%s", oc->url);

         } else {

             filename = av_asprintf("%s", oc->url);

         }
         if (!filename) {

             av_freep(&old_filename);

             return AVERROR(ENOMEM);
         }
 

         if (hls->segment_type == SEGMENT_TYPE_FMP4) {

             int range_length = 0;

             if (!vs->init_range_length) {

                 uint8_t *buffer = NULL;

                 av_write_frame(oc, NULL); /* Flush any buffered data */

                 range_length = avio_close_dyn_buf(oc->pb, &buffer);

                 avio_write(vs->out, buffer, range_length);

                 av_freep(&buffer);

                 vs->init_range_length = range_length;
                 avio_open_dyn_buf(&oc->pb);
                 vs->packets_written = 0;
                 vs->start_pos = range_length;

                 byterange_mode = (hls->flags & HLS_SINGLE_FILE) || (hls->max_seg_size > 0);

                 if (!byterange_mode) {
                     ff_format_io_close(s, &vs->out);
                     hlsenc_io_close(s, &vs->out, vs->base_output_dirname);
                 }
             }

         }
         if (!(hls->flags & HLS_SINGLE_FILE)) {
             set_http_options(s, &options, hls);
             ret = hlsenc_io_open(s, &vs->out, filename, &options);

             if (ret < 0) {

                 av_log(s, AV_LOG_ERROR, "Failed to open file '%s'\n", oc->url);

                 goto failed;
             }

             if (hls->segment_type == SEGMENT_TYPE_FMP4)
                 write_styp(vs->out);

         }

         ret = flush_dynbuf(vs, &range_length);
         if (ret < 0)
             goto failed;
 
         vs->size = range_length;
         hlsenc_io_close(s, &vs->out, filename);

         ret = hlsenc_io_close(s, &vs->out, filename);
         if (ret < 0) {
             av_log(s, AV_LOG_WARNING, "upload segment failed, will retry with a new http session.\n");
             ff_format_io_close(s, &vs->out);
             ret = hlsenc_io_open(s, &vs->out, filename, &options);
             if (ret < 0) {

                 av_log(s, AV_LOG_ERROR, "Failed to open file '%s'\n", oc->url);

                 goto failed;
             }
             reflush_dynbuf(vs, &range_length);
             ret = hlsenc_io_close(s, &vs->out, filename);

             if (ret < 0)

                 av_log(s, AV_LOG_WARNING, "Failed to upload file '%s' at the end.\n", oc->url);

         }
 

 failed:

         av_freep(&vs->temp_buffer);
         av_dict_free(&options);

         av_freep(&filename);

         av_write_trailer(oc);

         if (oc->url[0]) {
             proto = avio_find_protocol_name(oc->url);
             use_temp_file = proto && !strcmp(proto, "file") && (hls->flags & HLS_TEMP_FILE);
         }
 

         // rename that segment from .tmp to the real one
         if (use_temp_file && !(hls->flags & HLS_SINGLE_FILE)) {
             hls_rename_temp_file(s, oc);

             av_freep(&old_filename);

             old_filename = av_strdup(oc->url);

             if (!old_filename) {
                 return AVERROR(ENOMEM);

             }

         }

         /* after av_write_trailer, then duration + 1 duration per packet */
         hls_append_segment(s, hls, vs, vs->duration + vs->dpp, vs->start_pos, vs->size);

         sls_flag_file_rename(hls, vs, old_filename);

         if (vtt_oc) {
             if (vtt_oc->pb)
                 av_write_trailer(vtt_oc);
             vs->size = avio_tell(vs->vtt_avf->pb) - vs->start_pos;
             ff_format_io_close(s, &vtt_oc->pb);
         }

         ret = hls_window(s, 1, vs);
         if (ret < 0) {
             av_log(s, AV_LOG_WARNING, "upload playlist failed, will retry with a new http session.\n");
             ff_format_io_close(s, &vs->out);
             hls_window(s, 1, vs);
         }

         ffio_free_dyn_buf(&oc->pb);

         av_free(old_filename);

     }
 

     return 0;
 }
 

 
 static int hls_init(AVFormatContext *s)
 {
     int ret = 0;
     int i = 0;
     int j = 0;
     HLSContext *hls = s->priv_data;

     const char *pattern;

     VariantStream *vs = NULL;

     const char *vtt_pattern = hls->flags & HLS_SINGLE_FILE ? ".vtt" : "%d.vtt";

     char *p = NULL;

     int http_base_proto = ff_is_http_proto(s->url);

     int fmp4_init_filename_len = strlen(hls->fmp4_init_filename) + 1;
 

     if (hls->use_localtime) {
         pattern = get_default_pattern_localtime_fmt(s);
     } else {
         pattern = hls->segment_type == SEGMENT_TYPE_FMP4 ? "%d.m4s" : "%d.ts";
         if (hls->flags & HLS_SINGLE_FILE)
             pattern += 2;
     }
 

     hls->has_default_key = 0;
     hls->has_video_m3u8 = 0;

     ret = update_variant_stream_info(s);
     if (ret < 0) {
         av_log(s, AV_LOG_ERROR, "Variant stream info update failed with status %x\n",

                ret);

         return ret;

     }
 

     if (!hls->method && http_base_proto) {

         av_log(hls, AV_LOG_WARNING, "No HTTP method set, hls muxer defaulting to method PUT.\n");

     }
 

     ret = validate_name(hls->nb_varstreams, s->url);

     if (ret < 0)

         return ret;

 
     if (hls->segment_filename) {
         ret = validate_name(hls->nb_varstreams, hls->segment_filename);
         if (ret < 0)

             return ret;

     }
 
     if (av_strcasecmp(hls->fmp4_init_filename, "init.mp4")) {
         ret = validate_name(hls->nb_varstreams, hls->fmp4_init_filename);
         if (ret < 0)

             return ret;

     }
 
     if (hls->subtitle_filename) {
         ret = validate_name(hls->nb_varstreams, hls->subtitle_filename);
         if (ret < 0)

             return ret;

     }
 

     if (hls->master_pl_name) {
         ret = update_master_pl_info(s);
         if (ret < 0) {
             av_log(s, AV_LOG_ERROR, "Master stream info update failed with status %x\n",

                    ret);

             return ret;

         }
     }
 
     if ((hls->start_sequence_source_type == HLS_START_SEQUENCE_AS_SECONDS_SINCE_EPOCH) ||

         (hls->start_sequence_source_type == HLS_START_SEQUENCE_AS_MICROSECONDS_SINCE_EPOCH) ||

         (hls->start_sequence_source_type == HLS_START_SEQUENCE_AS_FORMATTED_DATETIME)) {

         time_t t = time(NULL);
         if (hls->start_sequence_source_type == HLS_START_SEQUENCE_AS_MICROSECONDS_SINCE_EPOCH) {
             hls->start_sequence = av_gettime();
         } else if (hls->start_sequence_source_type == HLS_START_SEQUENCE_AS_SECONDS_SINCE_EPOCH) {

             hls->start_sequence = (int64_t)t;
         } else if (hls->start_sequence_source_type == HLS_START_SEQUENCE_AS_FORMATTED_DATETIME) {
             char b[15];
             struct tm *p, tmbuf;
             if (!(p = localtime_r(&t, &tmbuf)))

                 return AVERROR(errno);

             if (!strftime(b, sizeof(b), "%Y%m%d%H%M%S", p))
                 return AVERROR(ENOMEM);
             hls->start_sequence = strtoll(b, NULL, 10);
         }
         av_log(hls, AV_LOG_DEBUG, "start_number evaluated to %"PRId64"\n", hls->start_sequence);
     }
 
     hls->recording_time = (hls->init_time ? hls->init_time : hls->time) * AV_TIME_BASE;

     if (hls->flags & HLS_SPLIT_BY_TIME && hls->flags & HLS_INDEPENDENT_SEGMENTS) {
         // Independent segments cannot be guaranteed when splitting by time
         hls->flags &= ~HLS_INDEPENDENT_SEGMENTS;
         av_log(s, AV_LOG_WARNING,
                "'split_by_time' and 'independent_segments' cannot be "
                "enabled together. Disabling 'independent_segments' flag\n");
     }

     for (i = 0; i < hls->nb_varstreams; i++) {
         vs = &hls->var_streams[i];

         ret = format_name(s->url, &vs->m3u8_name, i, vs->varname);

         if (ret < 0)

             return ret;

         vs->sequence  = hls->start_sequence;
         vs->start_pts = AV_NOPTS_VALUE;
         vs->end_pts   = AV_NOPTS_VALUE;

         vs->current_segment_final_filename_fmt[0] = '\0';
 
         if (hls->flags & HLS_PROGRAM_DATE_TIME) {
             time_t now0;
             time(&now0);
             vs->initial_prog_date_time = now0;
         }
 
         for (j = 0; j < vs->nb_streams; j++) {
             vs->has_video += vs->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO;

             /* Get one video stream to reference for split segments
              * so use the first video stream index. */
             if ((vs->has_video == 1) && (vs->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_VIDEO)) {

                 vs->reference_stream_index = vs->streams[j]->index;

             }

             vs->has_subtitle += vs->streams[j]->codecpar->codec_type == AVMEDIA_TYPE_SUBTITLE;
         }
 
         if (vs->has_video > 1)
             av_log(s, AV_LOG_WARNING, "More than a single video stream present, expect issues decoding it.\n");
         if (hls->segment_type == SEGMENT_TYPE_FMP4) {
             vs->oformat = av_guess_format("mp4", NULL, NULL);
         } else {
             vs->oformat = av_guess_format("mpegts", NULL, NULL);
         }

         if (!vs->oformat)
             return AVERROR_MUXER_NOT_FOUND;

 
         if (hls->segment_filename) {

             ret = format_name(hls->segment_filename, &vs->basename, i, vs->varname);

             if (ret < 0)

                 return ret;

         } else {

             p = strrchr(vs->m3u8_name, '.');
             if (p)
                 *p = '\0';

             vs->basename = av_asprintf("%s%s", vs->m3u8_name, pattern);

             if (!vs->basename)
                 return AVERROR(ENOMEM);

 
             if (p)

                 *p = '.';

         }
 
         if (hls->segment_type == SEGMENT_TYPE_FMP4) {
             if (hls->nb_varstreams > 1)
                 fmp4_init_filename_len += strlen(POSTFIX_PATTERN);

             if (hls->flags & HLS_SINGLE_FILE) {
                 vs->fmp4_init_filename  = av_strdup(vs->basename);

                 if (!vs->fmp4_init_filename)
                     return AVERROR(ENOMEM);

             } else {

                 vs->fmp4_init_filename = av_malloc(fmp4_init_filename_len);

                 if (!vs->fmp4_init_filename)
                     return AVERROR(ENOMEM);

                 av_strlcpy(vs->fmp4_init_filename, hls->fmp4_init_filename,
                            fmp4_init_filename_len);
                 if (hls->nb_varstreams > 1) {

                     if (av_stristr(vs->fmp4_init_filename, "%v")) {

                         av_freep(&vs->fmp4_init_filename);

                         ret = format_name(hls->fmp4_init_filename,
                                           &vs->fmp4_init_filename, i, vs->varname);

                     } else {
                         ret = append_postfix(vs->fmp4_init_filename, fmp4_init_filename_len, i);
                     }

                     if (ret < 0)

                         return ret;

                 }

                 p = strrchr(vs->m3u8_name, '/');

                 if (p) {

                     char tmp = *(++p);
                     *p = '\0';
                     vs->base_output_dirname = av_asprintf("%s%s", vs->m3u8_name,
                                                           vs->fmp4_init_filename);
                     *p = tmp;

                 } else {

                     vs->base_output_dirname = av_strdup(vs->fmp4_init_filename);

                 }

                 if (!vs->base_output_dirname)
                     return AVERROR(ENOMEM);

             }

         }
 

         ret = hls->use_localtime ? sls_flag_check_duration_size(hls, vs) : sls_flag_check_duration_size_index(hls);
         if (ret < 0)

             return ret;

         if (vs->has_subtitle) {

             vs->vtt_oformat = av_guess_format("webvtt", NULL, NULL);
             if (!vs->vtt_oformat)
                 return AVERROR_MUXER_NOT_FOUND;

             p = strrchr(vs->m3u8_name, '.');
             if (p)
                 *p = '\0';

             vs->vtt_basename = av_asprintf("%s%s", vs->m3u8_name, vtt_pattern);

             if (!vs->vtt_basename)
                 return AVERROR(ENOMEM);

             if (hls->subtitle_filename) {

                 ret = format_name(hls->subtitle_filename, &vs->vtt_m3u8_name, i, vs->varname);

                 if (ret < 0)

                     return ret;

             } else {

                 vs->vtt_m3u8_name = av_asprintf("%s_vtt.m3u8", vs->m3u8_name);

                 if (!vs->vtt_m3u8_name)
                     return AVERROR(ENOMEM);

             }

             if (p)
                 *p = '.';

         }
 
         if ((ret = hls_mux_init(s, vs)) < 0)

             return ret;

 
         if (hls->flags & HLS_APPEND_LIST) {
             parse_playlist(s, vs->m3u8_name, vs);
             vs->discontinuity = 1;
             if (hls->init_time > 0) {
                 av_log(s, AV_LOG_WARNING, "append_list mode does not support hls_init_time,"
                        " hls_init_time value will have no effect\n");
                 hls->init_time = 0;
                 hls->recording_time = hls->time * AV_TIME_BASE;
             }
         }
 

         if ((ret = hls_start(s, vs)) < 0)

             return ret;

         vs->number++;

     }
 
     return ret;
 }
 

 #define OFFSET(x) offsetof(HLSContext, x)
 #define E AV_OPT_FLAG_ENCODING_PARAM
 static const AVOption options[] = {

     {"start_number",  "set first number in the sequence",        OFFSET(start_sequence),AV_OPT_TYPE_INT64,  {.i64 = 0},     0, INT64_MAX, E},

     {"hls_time",      "set segment length in seconds",           OFFSET(time),    AV_OPT_TYPE_FLOAT,  {.dbl = 2},     0, FLT_MAX, E},

     {"hls_init_time", "set segment length in seconds at init list",           OFFSET(init_time),    AV_OPT_TYPE_FLOAT,  {.dbl = 0},     0, FLT_MAX, E},

     {"hls_list_size", "set maximum number of playlist entries",  OFFSET(max_nb_segments),    AV_OPT_TYPE_INT,    {.i64 = 5},     0, INT_MAX, E},

     {"hls_delete_threshold", "set number of unreferenced segments to keep before deleting",  OFFSET(hls_delete_threshold),    AV_OPT_TYPE_INT,    {.i64 = 1},     1, INT_MAX, E},

     {"hls_ts_options","set hls mpegts list of options for the container format used for hls", OFFSET(format_options), AV_OPT_TYPE_DICT, {.str = NULL},  0, 0,    E},

     {"hls_vtt_options","set hls vtt list of options for the container format used for hls", OFFSET(vtt_format_options_str), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},

 #if FF_API_HLS_WRAP
     {"hls_wrap",      "set number after which the index wraps (will be deprecated)",  OFFSET(wrap),    AV_OPT_TYPE_INT,    {.i64 = 0},     0, INT_MAX, E},
 #endif

     {"hls_allow_cache", "explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments", OFFSET(allowcache), AV_OPT_TYPE_INT, {.i64 = -1}, INT_MIN, INT_MAX, E},

     {"hls_base_url",  "url to prepend to each playlist entry",   OFFSET(baseurl), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       E},

     {"hls_segment_filename", "filename template for segment files", OFFSET(segment_filename),   AV_OPT_TYPE_STRING, {.str = NULL},            0,       0,         E},

     {"hls_segment_size", "maximum size per segment file, (in bytes)",  OFFSET(max_seg_size),    AV_OPT_TYPE_INT,    {.i64 = 0},               0,       INT_MAX,   E},

     {"hls_key_info_file",    "file with key URI and key file path", OFFSET(key_info_file),      AV_OPT_TYPE_STRING, {.str = NULL},            0,       0,         E},

     {"hls_enc",    "enable AES128 encryption support", OFFSET(encrypt),      AV_OPT_TYPE_BOOL, {.i64 = 0},            0,       1,         E},
     {"hls_enc_key",    "hex-coded 16 byte key to encrypt the segments", OFFSET(key),      AV_OPT_TYPE_STRING, .flags = E},
     {"hls_enc_key_url",    "url to access the key to decrypt the segments", OFFSET(key_url),      AV_OPT_TYPE_STRING, {.str = NULL},            0,       0,         E},
     {"hls_enc_iv",    "hex-coded 16 byte initialization vector", OFFSET(iv),      AV_OPT_TYPE_STRING, .flags = E},

     {"hls_subtitle_path",     "set path of hls subtitles", OFFSET(subtitle_filename), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},

     {"hls_segment_type",     "set hls segment files type", OFFSET(segment_type), AV_OPT_TYPE_INT, {.i64 = SEGMENT_TYPE_MPEGTS }, 0, SEGMENT_TYPE_FMP4, E, "segment_type"},

     {"mpegts",   "make segment file to mpegts files in m3u8", 0, AV_OPT_TYPE_CONST, {.i64 = SEGMENT_TYPE_MPEGTS }, 0, UINT_MAX,   E, "segment_type"},

     {"fmp4",   "make segment file to fragment mp4 files in m3u8", 0, AV_OPT_TYPE_CONST, {.i64 = SEGMENT_TYPE_FMP4 }, 0, UINT_MAX,   E, "segment_type"},

     {"hls_fmp4_init_filename", "set fragment mp4 file init filename", OFFSET(fmp4_init_filename),   AV_OPT_TYPE_STRING, {.str = "init.mp4"},            0,       0,         E},

     {"hls_fmp4_init_resend", "resend fragment mp4 init file after refresh m3u8 every time", OFFSET(resend_init_file), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },

     {"hls_flags",     "set flags affecting HLS playlist and media file generation", OFFSET(flags), AV_OPT_TYPE_FLAGS, {.i64 = 0 }, 0, UINT_MAX, E, "flags"},
     {"single_file",   "generate a single media file indexed with byte ranges", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_SINGLE_FILE }, 0, UINT_MAX,   E, "flags"},

     {"temp_file", "write segment and playlist to temporary file and rename when complete", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_TEMP_FILE }, 0, UINT_MAX,   E, "flags"},

     {"delete_segments", "delete segment files that are no longer part of the playlist", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_DELETE_SEGMENTS }, 0, UINT_MAX,   E, "flags"},

     {"round_durations", "round durations in m3u8 to whole numbers", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_ROUND_DURATIONS }, 0, UINT_MAX,   E, "flags"},

     {"discont_start", "start the playlist with a discontinuity tag", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_DISCONT_START }, 0, UINT_MAX,   E, "flags"},

     {"omit_endlist", "Do not append an endlist when ending stream", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_OMIT_ENDLIST }, 0, UINT_MAX,   E, "flags"},

     {"split_by_time", "split the hls segment by time which user set by hls_time", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_SPLIT_BY_TIME }, 0, UINT_MAX,   E, "flags"},

     {"append_list", "append the new segments into old hls segment list", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_APPEND_LIST }, 0, UINT_MAX,   E, "flags"},

     {"program_date_time", "add EXT-X-PROGRAM-DATE-TIME", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_PROGRAM_DATE_TIME }, 0, UINT_MAX,   E, "flags"},

     {"second_level_segment_index", "include segment index in segment filenames when use_localtime", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_SECOND_LEVEL_SEGMENT_INDEX }, 0, UINT_MAX,   E, "flags"},

     {"second_level_segment_duration", "include segment duration in segment filenames when use_localtime", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_SECOND_LEVEL_SEGMENT_DURATION }, 0, UINT_MAX,   E, "flags"},
     {"second_level_segment_size", "include segment size in segment filenames when use_localtime", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_SECOND_LEVEL_SEGMENT_SIZE }, 0, UINT_MAX,   E, "flags"},

     {"periodic_rekey", "reload keyinfo file periodically for re-keying", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_PERIODIC_REKEY }, 0, UINT_MAX,   E, "flags"},

     {"independent_segments", "add EXT-X-INDEPENDENT-SEGMENTS, whenever applicable", 0, AV_OPT_TYPE_CONST, { .i64 = HLS_INDEPENDENT_SEGMENTS }, 0, UINT_MAX, E, "flags"},

     {"iframes_only", "add EXT-X-I-FRAMES-ONLY, whenever applicable", 0, AV_OPT_TYPE_CONST, { .i64 = HLS_I_FRAMES_ONLY }, 0, UINT_MAX, E, "flags"},

 #if FF_API_HLS_USE_LOCALTIME

     {"use_localtime", "set filename expansion with strftime at segment creation(will be deprecated)", OFFSET(use_localtime), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },

 #endif
     {"strftime", "set filename expansion with strftime at segment creation", OFFSET(use_localtime), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },
 #if FF_API_HLS_USE_LOCALTIME
     {"use_localtime_mkdir", "create last directory component in strftime-generated filename(will be deprecated)", OFFSET(use_localtime_mkdir), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },
 #endif
     {"strftime_mkdir", "create last directory component in strftime-generated filename", OFFSET(use_localtime_mkdir), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },

     {"hls_playlist_type", "set the HLS playlist type", OFFSET(pl_type), AV_OPT_TYPE_INT, {.i64 = PLAYLIST_TYPE_NONE }, 0, PLAYLIST_TYPE_NB-1, E, "pl_type" },
     {"event", "EVENT playlist", 0, AV_OPT_TYPE_CONST, {.i64 = PLAYLIST_TYPE_EVENT }, INT_MIN, INT_MAX, E, "pl_type" },
     {"vod", "VOD playlist", 0, AV_OPT_TYPE_CONST, {.i64 = PLAYLIST_TYPE_VOD }, INT_MIN, INT_MAX, E, "pl_type" },

     {"method", "set the HTTP method(default: PUT)", OFFSET(method), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},

     {"hls_start_number_source", "set source of first number in sequence", OFFSET(start_sequence_source_type), AV_OPT_TYPE_INT, {.i64 = HLS_START_SEQUENCE_AS_START_NUMBER }, 0, HLS_START_SEQUENCE_LAST-1, E, "start_sequence_source_type" },

     {"generic", "start_number value (default)", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_START_SEQUENCE_AS_START_NUMBER }, INT_MIN, INT_MAX, E, "start_sequence_source_type" },
     {"epoch", "seconds since epoch", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_START_SEQUENCE_AS_SECONDS_SINCE_EPOCH }, INT_MIN, INT_MAX, E, "start_sequence_source_type" },

     {"epoch_us", "microseconds since epoch", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_START_SEQUENCE_AS_MICROSECONDS_SINCE_EPOCH }, INT_MIN, INT_MAX, E, "start_sequence_source_type" },

     {"datetime", "current datetime as YYYYMMDDhhmmss", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_START_SEQUENCE_AS_FORMATTED_DATETIME }, INT_MIN, INT_MAX, E, "start_sequence_source_type" },

     {"http_user_agent", "override User-Agent field in HTTP header", OFFSET(user_agent), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},

     {"var_stream_map", "Variant stream map string", OFFSET(var_stream_map), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},

     {"cc_stream_map", "Closed captions stream map string", OFFSET(cc_stream_map), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},

     {"master_pl_name", "Create HLS master playlist with this name", OFFSET(master_pl_name), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},
     {"master_pl_publish_rate", "Publish master play list every after this many segment intervals", OFFSET(master_publish_rate), AV_OPT_TYPE_INT, {.i64 = 0}, 0, UINT_MAX, E},

     {"http_persistent", "Use persistent HTTP connections", OFFSET(http_persistent), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },

     {"timeout", "set timeout for socket I/O operations", OFFSET(timeout), AV_OPT_TYPE_DURATION, { .i64 = -1 }, -1, INT_MAX, .flags = E },

     {"ignore_io_errors", "Ignore IO errors for stable long-duration runs with network output", OFFSET(ignore_io_errors), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E },

     {"headers", "set custom HTTP headers, can override built in default headers", OFFSET(headers), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, E },

     { NULL },
 };
 
 static const AVClass hls_class = {
     .class_name = "hls muxer",
     .item_name  = av_default_item_name,
     .option     = options,
     .version    = LIBAVUTIL_VERSION_INT,
 };
 
 
 AVOutputFormat ff_hls_muxer = {
     .name           = "hls",

     .long_name      = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),

     .extensions     = "m3u8",
     .priv_data_size = sizeof(HLSContext),

     .audio_codec    = AV_CODEC_ID_AAC,
     .video_codec    = AV_CODEC_ID_H264,

     .subtitle_codec = AV_CODEC_ID_WEBVTT,

     .flags          = AVFMT_NOFILE | AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH | AVFMT_NODIMENSIONS,

     .init           = hls_init,

     .write_header   = hls_write_header,
     .write_packet   = hls_write_packet,
     .write_trailer  = hls_write_trailer,

     .deinit         = hls_deinit,

     .priv_class     = &hls_class,
 };