[FFmpeg-devel] [PATCH v11] avformat/dashdec: add dash demuxer base version

Steven Liu lingjiujianke at gmail.com
Thu Mar 30 17:51:12 EEST 2017


2017-03-30 20:59 GMT+08:00 Steven Liu <lingjiujianke at gmail.com>:

>
>
> 2017-03-30 18:46 GMT+08:00 wm4 <nfxjfg at googlemail.com>:
>
>> On Thu, 30 Mar 2017 08:34:18 +0800
>> Steven Liu <lq at chinaffmpeg.org> wrote:
>>
>> > v2 fixed:
>> > 1. from autodetect to disabled
>> > 2. from camelCase code style to ffmpeg code style
>> > 3. from RepType to AVMediaType
>> > 4. fix variable typo
>> > 5. change time value from uint32_t to uint64_t
>> > 6. removed be used once API
>> > 7. change 'time(NULL)`, except it is not 2038-safe.' to av_gettime and
>> av_timegm
>> > 8. merge complex free operation to free_fragment
>> > 9. use API from snprintf to av_asprintf
>> >
>> > v3 fixed:
>> > 1. fix typo from --enabled-xml2 to --enable-xml2
>> >
>> > v4 fixed:
>> > 1. from --enable-xml2 to --enable-libxml2
>> > 2. move system includes to top
>> > 3. remove nouse includes
>> > 4. rename enum name
>> > 5. add a trailing comma for the last entry enum
>> > 6. fix comment typo
>> > 7. add const to DASHContext class front
>> > 8. check sscanf if return arguments and give warning message when error
>> > 9. check validity before free seg->url and seg
>> > 10. check if the val is null, before use atoll
>> >
>> > v5 fixed:
>> > 1. fix typo from mainifest to manifest
>> >
>> > v6 fixed:
>> > 1. from realloc to av_realloc
>> > 2. from free to av_free
>> >
>> > v7 fixed:
>> > 1. remove the -lxml2 from configure when require_pkg_config
>> >
>> > v8 fixed:
>> > 1. fix replace filename template by av_asprintf secure problem
>> >
>> > v9 modified:
>> > 1. make manifest parser clearly
>> >
>> > v10 fixed:
>> > 1. fix function API name code style
>> > 2. remove redundant strreplace call
>> > 3. remove redundant memory operation and check return value from
>> get_content_url()
>> > 4. add space between ) and {
>> > 5. remove no need to log the value for print
>> >
>> > v11 fixed:
>> > 1. from atoll to strtoll
>> >
>> > Reviewed-by: Clément Bœsch <u at pkh.me>
>> > Reviewed-by: Michael Niedermayer <michael at niedermayer.cc>
>> > Reviewed-by: Carl Eugen Hoyos <cehoyos at ag.or.at>
>> > Reviewed-by: Rodger Combs <rodger.combs at gmail.com>
>> > Reviewed-by: Moritz Barsnick <barsnick at gmx.net>
>> > Reviewed-by: Nicolas George <george at nsup.org>
>> > Reviewed-by: Ricardo Constantino <wiiaboo at gmail.com>
>> > Signed-off-by: Steven Liu <lq at chinaffmpeg.org>
>> > ---
>> >  configure                |    4 +
>> >  libavformat/Makefile     |    1 +
>> >  libavformat/allformats.c |    2 +-
>> >  libavformat/dashdec.c    | 1851 ++++++++++++++++++++++++++++++
>> ++++++++++++++++
>> >  4 files changed, 1857 insertions(+), 1 deletion(-)
>> >  create mode 100644 libavformat/dashdec.c
>> >
>> > diff --git a/configure b/configure
>> > index 9cc7e7d..4a6fe8a 100755
>> > --- a/configure
>> > +++ b/configure
>> > @@ -273,6 +273,7 @@ External library support:
>> >    --enable-libxcb-shape    enable X11 grabbing shape rendering
>> [autodetect]
>> >    --enable-libxvid         enable Xvid encoding via xvidcore,
>> >                             native MPEG-4/Xvid encoder exists [no]
>> > +  --enable-libxml2            enable XML parsing using the C library
>> libxml2 [no]
>> >    --enable-libzimg         enable z.lib, needed for zscale filter [no]
>> >    --enable-libzmq          enable message passing via libzmq [no]
>> >    --enable-libzvbi         enable teletext support via libzvbi [no]
>> > @@ -1574,6 +1575,7 @@ EXTERNAL_LIBRARY_LIST="
>> >      libvpx
>> >      libwavpack
>> >      libwebp
>> > +    libxml2
>> >      libzimg
>> >      libzmq
>> >      libzvbi
>> > @@ -2906,6 +2908,7 @@ avi_muxer_select="riffenc"
>> >  caf_demuxer_select="iso_media riffdec"
>> >  caf_muxer_select="iso_media"
>> >  dash_muxer_select="mp4_muxer"
>> > +dash_demuxer_deps="libxml2"
>> >  dirac_demuxer_select="dirac_parser"
>> >  dts_demuxer_select="dca_parser"
>> >  dtshd_demuxer_select="dca_parser"
>> > @@ -5908,6 +5911,7 @@ enabled openssl           && { use_pkg_config
>> openssl openssl/ssl.h OPENSSL_init
>> >                                 check_lib openssl/ssl.h
>> SSL_library_init -lssl -lcrypto -lws2_32 -lgdi32 ||
>> >                                 die "ERROR: openssl not found"; }
>> >  enabled qtkit_indev      && { check_header_objcc QTKit/QTKit.h ||
>> disable qtkit_indev; }
>> > +enabled libxml2             && require_pkg_config libxml-2.0
>> libxml2/libxml/xmlversion.h xmlCheckVersion
>> >
>> >  # libdc1394 check
>> >  if enabled libdc1394; then
>> > diff --git a/libavformat/Makefile b/libavformat/Makefile
>> > index f56ef16..d77ffaa 100644
>> > --- a/libavformat/Makefile
>> > +++ b/libavformat/Makefile
>> > @@ -134,6 +134,7 @@ OBJS-$(CONFIG_CRC_MUXER)                 += crcenc.o
>> >  OBJS-$(CONFIG_DATA_DEMUXER)              += rawdec.o
>> >  OBJS-$(CONFIG_DATA_MUXER)                += rawenc.o
>> >  OBJS-$(CONFIG_DASH_MUXER)                += dashenc.o
>> > +OBJS-$(CONFIG_DASH_DEMUXER)              += dashdec.o
>> >  OBJS-$(CONFIG_DAUD_DEMUXER)              += dauddec.o
>> >  OBJS-$(CONFIG_DAUD_MUXER)                += daudenc.o
>> >  OBJS-$(CONFIG_DCSTR_DEMUXER)             += dcstr.o
>> > diff --git a/libavformat/allformats.c b/libavformat/allformats.c
>> > index 09e62c3..d57314b 100644
>> > --- a/libavformat/allformats.c
>> > +++ b/libavformat/allformats.c
>> > @@ -96,7 +96,7 @@ static void register_all(void)
>> >      REGISTER_DEMUXER (CINE,             cine);
>> >      REGISTER_DEMUXER (CONCAT,           concat);
>> >      REGISTER_MUXER   (CRC,              crc);
>> > -    REGISTER_MUXER   (DASH,             dash);
>> > +    REGISTER_MUXDEMUX(DASH,             dash);
>> >      REGISTER_MUXDEMUX(DATA,             data);
>> >      REGISTER_MUXDEMUX(DAUD,             daud);
>> >      REGISTER_DEMUXER (DCSTR,            dcstr);
>> > diff --git a/libavformat/dashdec.c b/libavformat/dashdec.c
>> > new file mode 100644
>> > index 0000000..ee69bc9
>> > --- /dev/null
>> > +++ b/libavformat/dashdec.c
>> > @@ -0,0 +1,1851 @@
>> > +/*
>> > + * Dynamic Adaptive Streaming over HTTP demux
>> > + * Copyright (c) 2017 samsamsam at o2.pl based on HLS demux
>> > + * Copyright (c) 2017 Steven Liu
>> > + *
>> > + * 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 <libxml/parser.h>
>> > +#include "libavutil/intreadwrite.h"
>> > +#include "libavutil/opt.h"
>> > +#include "libavutil/time.h"
>> > +#include "libavutil/parseutils.h"
>> > +#include "internal.h"
>> > +#include "avio_internal.h"
>> > +
>> > +#define INITIAL_BUFFER_SIZE 32768
>> > +
>> > +struct fragment {
>> > +    int64_t url_offset;
>> > +    int64_t size;
>> > +    char *url;
>> > +};
>> > +
>> > +/*
>> > + * reference to : ISO_IEC_23009-1-DASH-2012
>> > + * Section: 5.3.9.6.2
>> > + * Table: Table 17 — Semantics of SegmentTimeline element
>> > + * */
>> > +struct timeline {
>> > +    /* t: Element or Attribute Name
>> > +     * specifies the MPD start time, in @timescale units,
>> > +     * the first Segment in the series starts relative to the
>> beginning of the Period.
>> > +     * The value of this attribute must be equal to or greater than
>> the sum of the previous S
>> > +     * element earliest presentation time and the sum of the
>> contiguous Segment durations.
>> > +     * If the value of the attribute is greater than what is expressed
>> by the previous S element,
>> > +     * it expresses discontinuities in the timeline.
>> > +     * If not present then the value shall be assumed to be zero for
>> the first S element
>> > +     * and for the subsequent S elements, the value shall be assumed
>> to be the sum of
>> > +     * the previous S element's earliest presentation time and
>> contiguous duration
>> > +     * (i.e. previous S at t + @d * (@r + 1)).
>> > +     * */
>> > +    int64_t t;
>> > +    /* r: Element or Attribute Name
>> > +     * specifies the repeat count of the number of following
>> contiguous Segments with
>> > +     * the same duration expressed by the value of @d. This value is
>> zero-based
>> > +     * (e.g. a value of three means four Segments in the contiguous
>> series).
>> > +     * */
>> > +    int64_t r;
>> > +    /* d: Element or Attribute Name
>> > +     * specifies the Segment duration, in units of the value of the
>> @timescale.
>> > +     * */
>> > +    int64_t d;
>> > +};
>> > +
>> > +enum DASHTmplUrlType {
>> > +    TMP_URL_TYPE_UNSPECIFIED,
>> > +    TMP_URL_TYPE_NUMBER,
>> > +    TMP_URL_TYPE_TIME,
>> > +};
>> > +
>> > +/*
>> > + * Each playlist has its own demuxer. If it is currently active,
>> > + * it has an opened AVIOContext too, and potentially an AVPacket
>> > + * containing the next packet from this stream.
>> > + */
>> > +struct representation {
>> > +    char *url_template;
>> > +    enum DASHTmplUrlType tmp_url_type;
>> > +    AVIOContext pb;
>> > +    AVIOContext *input;
>> > +    AVFormatContext *parent;
>> > +    AVFormatContext *ctx;
>> > +    AVPacket pkt;
>> > +    int rep_idx;
>> > +    int rep_count;
>> > +    int stream_index;
>> > +
>> > +    enum AVMediaType type;
>> > +    int64_t target_duration;
>> > +
>> > +    int n_fragments;
>> > +    struct fragment **fragments; /* VOD list of fragment for profile */
>> > +
>> > +    int n_timelines;
>> > +    struct timeline **timelines;
>> > +
>> > +    int64_t first_seq_no;
>> > +    int64_t last_seq_no;
>> > +
>> > +    int64_t fragment_duration;
>> > +    int64_t fragment_timescale;
>> > +
>> > +    int64_t cur_seq_no;
>> > +    int64_t cur_seg_offset;
>> > +    int64_t cur_seg_size;
>> > +    struct fragment *cur_seg;
>> > +
>> > +    /* Currently active Media Initialization Section */
>> > +    struct fragment *init_section;
>> > +    uint8_t *init_sec_buf;
>> > +    uint32_t init_sec_buf_size;
>> > +    uint32_t init_sec_data_len;
>> > +    uint32_t init_sec_buf_read_offset;
>> > +    int fix_multiple_stsd_order;
>> > +    int64_t cur_timestamp;
>> > +};
>> > +
>> > +typedef struct DASHContext {
>> > +    const AVClass *class;
>> > +    char *base_url;
>> > +    struct representation *cur_video;
>> > +    struct representation *cur_audio;
>> > +    uint64_t media_presentation_duration_sec;
>> > +    uint64_t suggested_presentation_delay_sec;
>> > +    uint64_t presentation_delay_sec;
>> > +    uint64_t availability_start_time_sec;
>> > +    uint64_t publish_time_sec;
>> > +    uint64_t minimum_update_period_sec;
>> > +    uint64_t time_shift_buffer_depth_sec;
>> > +    uint64_t min_buffer_time_sec;
>> > +    uint64_t period_duration_sec;
>> > +    uint64_t period_start_sec;
>> > +    int is_live;
>> > +    AVIOInterruptCB *interrupt_callback;
>> > +    char *user_agent;                    ///< holds HTTP user agent
>> set as an AVOption to the HTTP protocol context
>> > +    char *cookies;                       ///< holds HTTP cookie values
>> set in either the initial response or as an AVOption to the HTTP protocol
>> context
>> > +    char *headers;                       ///< holds HTTP headers set
>> as an AVOption to the HTTP protocol context
>> > +    AVDictionary *avio_opts;
>> > +} DASHContext;
>> > +
>> > +static uint64_t get_current_time_in_sec(void)
>> > +{
>> > +    return  av_gettime() / 1000000;
>> > +}
>> > +
>> > +static uint64_t get_utc_date_time_insec(AVFormatContext *s, const
>> char *datetime)
>> > +{
>> > +    struct tm timeinfo;
>> > +    int year = 0;
>> > +    int month = 0;
>> > +    int day = 0;
>> > +    int hour = 0;
>> > +    int minute = 0;
>> > +    int ret = 0;
>> > +    float second = 0.0;
>> > +
>> > +    /* ISO-8601 date parser */
>> > +    if (!datetime)
>> > +        return 0;
>> > +
>> > +    ret = sscanf(datetime, "%d-%d-%dT%d:%d:%fZ", &year, &month, &day,
>> &hour, &minute, &second);
>> > +    /* year, month, day, hour, minute, second  6 arguments */
>> > +    if (ret != 6) {
>> > +        av_log(s, AV_LOG_WARNING, "get_utc_date_time_insec get a wrong
>> time format\n");
>> > +        // return 0; /* parser error */
>> > +    }
>> > +    timeinfo.tm_year = year - 1900;
>> > +    timeinfo.tm_mon  = month - 1;
>> > +    timeinfo.tm_mday = day;
>> > +    timeinfo.tm_hour = hour;
>> > +    timeinfo.tm_min  = minute;
>> > +    timeinfo.tm_sec  = (int)second;
>> > +
>> > +    return av_timegm(&timeinfo);
>> > +}
>> > +
>> > +static uint32_t get_duration_insec(AVFormatContext *s, const char
>> *duration)
>> > +{
>> > +    /* ISO-8601 duration parser */
>> > +    uint32_t days = 0;
>> > +    uint32_t hours = 0;
>> > +    uint32_t mins = 0;
>> > +    uint32_t secs = 0;
>> > +    uint32_t size = 0;
>> > +    float value = 0;
>> > +    uint8_t type = 0;
>> > +    const char *ptr = duration;
>> > +
>> > +    while (*ptr) {
>> > +        if (*ptr == 'P' || *ptr == 'T') {
>> > +            ptr++;
>> > +            continue;
>> > +        }
>> > +
>> > +        if (sscanf(ptr, "%f%c%n", &value, &type, &size) != 2) {
>> > +            av_log(s, AV_LOG_WARNING, "get_duration_insec get a wrong
>> time format\n");
>> > +            return 0; /* parser error */
>> > +        }
>> > +        switch (type) {
>> > +            case 'D':
>> > +                days = (uint32_t)value;
>> > +                break;
>> > +            case 'H':
>> > +                hours = (uint32_t)value;
>> > +                break;
>> > +            case 'M':
>> > +                mins = (uint32_t)value;
>> > +                break;
>> > +            case 'S':
>> > +                secs = (uint32_t)value;
>> > +                break;
>> > +            default:
>> > +                // handle invalid type
>> > +                break;
>> > +        }
>> > +        ptr += size;
>> > +    }
>> > +    return  ((days * 24 + hours) * 60 + mins) * 60 + secs;
>> > +}
>> > +
>> > +static void free_fragment(struct fragment **seg)
>> > +{
>> > +    if (!(*seg)) {
>> > +        return;
>> > +    }
>> > +    av_freep(&(*seg)->url);
>> > +    av_freep(seg);
>> > +}
>> > +
>> > +static void free_fragment_list(struct representation *pls)
>> > +{
>> > +    int i;
>> > +
>> > +    for (i = 0; i < pls->n_fragments; i++) {
>> > +        free_fragment(&pls->fragments[i]);
>> > +    }
>> > +    av_freep(&pls->fragments);
>> > +    pls->n_fragments = 0;
>> > +}
>> > +
>> > +static void free_timelines_list(struct representation *pls)
>> > +{
>> > +    int i;
>> > +
>> > +    for (i = 0; i < pls->n_timelines; i++) {
>> > +        av_freep(&pls->timelines[i]);
>> > +    }
>> > +    av_freep(&pls->timelines);
>> > +    pls->n_timelines = 0;
>> > +}
>> > +
>> > +/*
>> > + * Used to reset a statically allocated AVPacket to a clean slate,
>> > + * containing no data.
>> > + */
>> > +static void reset_packet(AVPacket *pkt)
>> > +{
>> > +    av_init_packet(pkt);
>> > +    pkt->data = NULL;
>> > +}
>> > +
>> > +static void free_representation(struct representation *pls)
>> > +{
>> > +    free_fragment_list(pls);
>> > +    free_timelines_list(pls);
>> > +    free_fragment(&pls->cur_seg);
>> > +    free_fragment(&pls->init_section);
>> > +    av_freep(&pls->init_sec_buf);
>> > +    av_packet_unref(&pls->pkt);
>> > +    reset_packet(&pls->pkt);
>> > +    av_freep(&pls->pb.buffer);
>> > +    if (pls->input)
>> > +        ff_format_io_close(pls->parent, &pls->input);
>> > +    if (pls->ctx) {
>> > +        pls->ctx->pb = NULL;
>> > +        avformat_close_input(&pls->ctx);
>> > +    }
>> > +
>> > +    av_free(pls->url_template);
>> > +    av_free(pls);
>> > +}
>> > +
>> > +static void update_options(char **dest, const char *name, void *src)
>> > +{
>> > +    av_freep(dest);
>> > +    av_opt_get(src, name, AV_OPT_SEARCH_CHILDREN, (uint8_t**)dest);
>> > +    if (*dest)
>> > +        av_freep(dest);
>> > +}
>> > +
>> > +static int open_url(AVFormatContext *s, AVIOContext **pb, const char
>> *url,
>> > +                    AVDictionary *opts, AVDictionary *opts2, int
>> *is_http)
>> > +{
>> > +    DASHContext *c = s->priv_data;
>> > +    AVDictionary *tmp = NULL;
>> > +    const char *proto_name = NULL;
>> > +    int ret;
>> > +
>> > +    av_dict_copy(&tmp, opts, 0);
>> > +    av_dict_copy(&tmp, opts2, 0);
>> > +
>> > +    if (av_strstart(url, "crypto", NULL)) {
>> > +        if (url[6] == '+' || url[6] == ':')
>> > +            proto_name = avio_find_protocol_name(url + 7);
>> > +    }
>> > +
>> > +    if (!proto_name)
>> > +        proto_name = avio_find_protocol_name(url);
>> > +
>> > +    if (!proto_name)
>> > +        return AVERROR_INVALIDDATA;
>> > +
>> > +    // only http(s) & file are allowed
>> > +    if (!av_strstart(proto_name, "http", NULL) &&
>> !av_strstart(proto_name, "file", NULL))
>> > +        return AVERROR_INVALIDDATA;
>> > +    if (!strncmp(proto_name, url, strlen(proto_name)) &&
>> url[strlen(proto_name)] == ':')
>> > +        ;
>> > +    else if (av_strstart(url, "crypto", NULL) && !strncmp(proto_name,
>> url + 7, strlen(proto_name)) && url[7 + strlen(proto_name)] == ':')
>> > +        ;
>> > +    else if (strcmp(proto_name, "file") || !strncmp(url, "file,", 5))
>> > +        return AVERROR_INVALIDDATA;
>>
>> Don't we have the protocol whitelist stuff for this?
>>
> This is copy from libavformat/hls.c
>
>
>>
>> > +
>> > +    ret = s->io_open(s, pb, url, AVIO_FLAG_READ, &tmp);
>> > +    if (ret >= 0) {
>> > +        // update cookies on http response with setcookies.
>> > +        void *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb;
>> > +        update_options(&c->cookies, "cookies", u);
>> > +        av_dict_set(&opts, "cookies", c->cookies, 0);
>> > +    }
>> > +
>> > +    av_dict_free(&tmp);
>> > +
>> > +    if (is_http)
>> > +        *is_http = av_strstart(proto_name, "http", NULL);
>> > +
>> > +    return ret;
>> > +
>> > +}
>> > +
>> > +static char *strreplace(const char *str, const char *from, const char
>> *to)
>> > +{
>> > +    /* Adjust each of the below values to suit your needs. */
>> > +    /* Increment positions cache size initially by this number. */
>> > +    size_t cache_sz_inc = 16;
>> > +    /* Thereafter, each time capacity needs to be increased,
>> > +     * multiply the increment by this factor. */
>> > +    const size_t cache_sz_inc_factor = 3;
>> > +    /* But never increment capacity by more than this number. */
>> > +    const size_t cache_sz_inc_max = 1048576;
>> > +
>> > +    char *pret, *ret = NULL;
>> > +    const char *pstr2, *pstr = str;
>> > +    size_t i, count = 0;
>> > +    uintptr_t *pos_cache_tmp, *pos_cache = NULL;
>> > +    size_t cache_sz = 0;
>> > +    size_t cpylen, orglen, retlen, tolen, fromlen = strlen(from);
>> > +
>> > +    /* Find all matches and cache their positions. */
>> > +    while ((pstr2 = av_stristr(pstr, from))) {
>> > +        count++;
>> > +        /* Increase the cache size when necessary. */
>> > +        if (cache_sz < count) {
>> > +            cache_sz += cache_sz_inc;
>> > +            pos_cache_tmp = av_realloc(pos_cache, sizeof(*pos_cache) *
>> cache_sz);
>> > +            if (!pos_cache_tmp) {
>> > +                goto end_strreplace;
>> > +            } else pos_cache = pos_cache_tmp;
>> > +            cache_sz_inc *= cache_sz_inc_factor;
>> > +            if (cache_sz_inc > cache_sz_inc_max) {
>> > +                cache_sz_inc = cache_sz_inc_max;
>> > +            }
>> > +        }
>> > +
>> > +        pos_cache[count-1] = pstr2 - str;
>> > +        pstr = pstr2 + fromlen;
>> > +    }
>> > +    orglen = pstr - str + strlen(pstr);
>> > +    /* Allocate memory for the post-replacement string. */
>> > +    if (count > 0) {
>> > +        tolen = strlen(to);
>> > +        retlen = orglen + (tolen - fromlen) * count;
>> > +    } else {
>> > +        retlen = orglen;
>> > +    }
>> > +    ret = av_malloc(retlen + 1);
>> > +    if (!ret) {
>> > +        goto end_strreplace;
>> > +    }
>> > +
>> > +    if (!count) {
>> > +        /* If no matches, then just duplicate the string. */
>> > +        av_strlcpy(ret, str, retlen + 1);
>> > +    } else {
>> > +        /* Otherwise, duplicate the string whilst performing
>> > +         * the replacements using the position cache. */
>> > +        pret = ret;
>> > +        memcpy(pret, str, pos_cache[0]);
>> > +        pret += pos_cache[0];
>> > +        for (i = 0; i < count; i++) {
>> > +            memcpy(pret, to, tolen);
>> > +            pret += tolen;
>> > +            pstr = str + pos_cache[i] + fromlen;
>> > +            cpylen = (i == count-1 ? orglen : pos_cache[i+1]) -
>> pos_cache[i] - fromlen;
>> > +            memcpy(pret, pstr, cpylen);
>> > +            pret += cpylen;
>> > +        }
>> > +        ret[retlen] = '\0';
>> > +    }
>> > +
>> > +end_strreplace:
>> > +    /* Free the cache and return the post-replacement string,
>> > +     * which will be NULL in the event of an error. */
>> > +    av_free(pos_cache);
>> > +    return ret;
>> > +}
>>
>> This function looks like it's copy pasted from
>> http://creativeandcritical.net/str-replace-c
>>
>> It should probably be placed into libavutil, with proper copyright
>> attribution. (If it even has a compatible license.)
>>
> ok, let me check the license with the str-replace-c author if we can add
> it into ffmpeg.
>
It can be moved into libavutil now, and i have make a patch.

>
>> > +static char *replace_template_str(const char *url, const char *marker)
>> > +{
>> > +    char *prefix = NULL;
>> > +    char *start = 0;
>> > +    char *end = NULL;
>> > +    char *tmp_url = NULL;
>> > +    int marker_len;
>> > +
>> > +    prefix = av_strdup(marker);
>> > +    marker_len = strlen(prefix) - 1;
>> > +    prefix[marker_len] = '\0';
>> > +
>> > +    start = av_stristr(url, prefix);
>> > +    if (!start)
>> > +        goto finish;
>> > +    end = strchr(start + 1, '$');
>> > +    if (!end)
>> > +        goto finish;
>> > +
>> > +    tmp_url = av_mallocz(MAX_URL_SIZE);
>> > +    if (!tmp_url) {
>> > +        return NULL;
>> > +    }
>> > +
>> > +    av_strlcpy(tmp_url, url, start - url+ 1);
>> > +    av_strlcat(tmp_url, start + marker_len, strlen(tmp_url) + end -
>> start - marker_len + 1);
>> > +    av_strlcat(tmp_url, end + 1, MAX_URL_SIZE);
>> > +
>> > +finish:
>> > +    av_free(prefix);
>> > +    return tmp_url;
>> > +}
>> > +
>> > +static char *get_content_url(xmlNodePtr *baseurl_nodes, int
>> n_baseurl_nodes, xmlChar *rep_id_val, xmlChar *rep_bandwidth_val, xmlChar
>> *val)
>> > +{
>> > +    int i;
>> > +    xmlChar *text;
>> > +    char *url = NULL;
>> > +    char *tmp_str = av_mallocz(MAX_URL_SIZE);
>> > +    char *tmp_str_2 = NULL;
>> > +
>> > +    if (!tmp_str) {
>> > +        return NULL;
>> > +    }
>> > +    for (i = 0; i < n_baseurl_nodes; ++i) {
>> > +        if (baseurl_nodes[i] && baseurl_nodes[i]->children &&
>> baseurl_nodes[i]->children->type == XML_TEXT_NODE) {
>> > +            text = xmlNodeGetContent(baseurl_nodes[i]->children);
>> > +            if (text) {
>> > +                tmp_str_2 = av_mallocz(MAX_URL_SIZE);
>> > +                if (!tmp_str_2) {
>> > +                    av_free(tmp_str);
>> > +                    return NULL;
>> > +                }
>> > +                ff_make_absolute_url(tmp_str_2, MAX_URL_SIZE,
>> tmp_str, text);
>> > +                av_free(tmp_str);
>> > +                tmp_str = tmp_str_2;
>> > +                xmlFree(text);
>> > +            }
>> > +        }
>> > +    }
>> > +    if (val)
>> > +        av_strlcat(tmp_str, (const char*)val, MAX_URL_SIZE);
>> > +    if (rep_id_val) {
>> > +        url = strreplace(tmp_str, "$RepresentationID$", (const
>> char*)rep_id_val);
>> > +        av_free(tmp_str);
>> > +        tmp_str = url;
>> > +    }
>> > +    if (rep_bandwidth_val && tmp_str)
>> > +        url = strreplace(tmp_str, "$Bandwidth$", (const
>> char*)rep_bandwidth_val);
>> > +    if (tmp_str != url)
>> > +        av_free(tmp_str);
>> > +    return url;
>> > +}
>> > +
>> > +static xmlChar *get_val_from_nodes_tab(xmlNodePtr *nodes, const int
>> n_nodes, const xmlChar *attrname)
>> > +{
>> > +    int i;
>> > +    xmlChar *val;
>> > +
>> > +    for (i = 0; i < n_nodes; ++i) {
>> > +        if (nodes[i]) {
>> > +            val = xmlGetProp(nodes[i], attrname);
>> > +            if (val)
>> > +                return val;
>> > +        }
>> > +    }
>> > +
>> > +    return NULL;
>> > +}
>> > +
>> > +static xmlNodePtr find_child_node_by_name(xmlNodePtr rootnode, const
>> xmlChar *nodename)
>> > +{
>> > +    xmlNodePtr node = rootnode;
>> > +    if (!node) {
>> > +        return NULL;
>> > +    }
>> > +
>> > +    node = xmlFirstElementChild(node);
>> > +    while (node) {
>> > +        if (!xmlStrcmp(node->name, nodename)) {
>> > +            return node;
>> > +        }
>> > +        node = xmlNextElementSibling(node);
>> > +    }
>> > +    return NULL;
>> > +}
>> > +
>> > +static enum AVMediaType get_content_type(xmlNodePtr node)
>> > +{
>> > +    enum AVMediaType type = AVMEDIA_TYPE_UNKNOWN;
>> > +    int i = 0;
>> > +    const char *attr;
>> > +
>> > +    if (node) {
>> > +        while (type == AVMEDIA_TYPE_UNKNOWN && i < 2) {
>> > +            attr = (i) ? "mimeType" : "contentType";
>> > +            xmlChar *val = xmlGetProp(node, attr);
>> > +            if (val) {
>> > +                if (av_stristr((const char *)val, "video")) {
>> > +                    type = AVMEDIA_TYPE_VIDEO;
>> > +                } else if (av_stristr((const char *)val, "audio")) {
>> > +                    type = AVMEDIA_TYPE_AUDIO;
>> > +                }
>> > +                xmlFree(val);
>> > +            }
>> > +            i++;
>> > +        }
>> > +    }
>> > +    return type;
>> > +}
>> > +
>> > +static int parse_manifest_segmenturlnode(AVFormatContext *s, struct
>> representation *rep,
>> > +                                         xmlNodePtr fragmenturl_node,
>> > +                                         xmlNodePtr *baseurl_nodes,
>> > +                                         xmlChar *rep_id_val,
>> > +                                         xmlChar *rep_bandwidth_val)
>> > +{
>> > +    xmlChar *initialization_val = NULL;
>> > +    xmlChar *media_val = NULL;
>> > +
>> > +    if (!xmlStrcmp(fragmenturl_node->name, (const xmlChar
>> *)"Initialization")) {
>> > +        initialization_val = xmlGetProp(fragmenturl_node, "sourceURL");
>> > +        if (initialization_val) {
>> > +            rep->init_section = av_mallocz(sizeof(struct fragment));
>> > +            if (!rep->init_section) {
>> > +                xmlFree(initialization_val);
>> > +                return AVERROR(ENOMEM);
>> > +            }
>> > +            rep->init_section->url = get_content_url(baseurl_nodes, 4,
>> rep_id_val, rep_bandwidth_val, initialization_val);
>> > +            if (!rep->init_section->url) {
>> > +                av_free(rep->init_section);
>> > +                xmlFree(initialization_val);
>> > +                return AVERROR(ENOMEM);
>> > +            }
>> > +            rep->init_section->size = -1;
>> > +            xmlFree(initialization_val);
>> > +        }
>> > +    } else if (!xmlStrcmp(fragmenturl_node->name, (const xmlChar
>> *)"SegmentURL")) {
>> > +        media_val = xmlGetProp(fragmenturl_node, "media");
>> > +        if (media_val) {
>> > +            struct fragment *seg = av_mallocz(sizeof(struct fragment));
>> > +            if (!seg) {
>> > +                xmlFree(media_val);
>> > +                return AVERROR(ENOMEM);
>> > +            }
>> > +            seg->url = get_content_url(baseurl_nodes, 4, rep_id_val,
>> rep_bandwidth_val, media_val);
>> > +            if (!seg->url) {
>> > +                av_free(seg);
>> > +                xmlFree(media_val);
>> > +                return AVERROR(ENOMEM);
>> > +            }
>> > +            seg->size = -1;
>> > +            dynarray_add(&rep->fragments, &rep->n_fragments, seg);
>> > +            xmlFree(media_val);
>> > +        }
>> > +    }
>> > +
>> > +    return 0;
>> > +}
>> > +
>> > +static int parse_manifest_segmenttimeline(AVFormatContext *s, struct
>> representation *rep,
>> > +                                          xmlNodePtr
>> fragment_timeline_node)
>> > +{
>> > +    xmlAttrPtr attr = NULL;
>> > +    xmlChar *val  = NULL;
>> > +
>> > +    if (!xmlStrcmp(fragment_timeline_node->name, (const xmlChar
>> *)"S")) {
>> > +        struct timeline *tml = av_mallocz(sizeof(struct timeline));
>> > +        if (!tml) {
>> > +            return AVERROR(ENOMEM);
>> > +        }
>> > +        attr = fragment_timeline_node->properties;
>> > +        while (attr) {
>> > +            val = xmlGetProp(fragment_timeline_node, attr->name);
>> > +
>> > +            if (!val) {
>> > +                av_log(s, AV_LOG_WARNING,
>> "parse_manifest_segmenttimeline attr->name = %s val is NULL\n",
>> attr->name);
>> > +                continue;
>> > +            }
>> > +
>> > +            if (!xmlStrcmp(attr->name, (const xmlChar *)"t")) {
>> > +                tml->t = (int64_t)strtoll(val, NULL, 10);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar *)"r")) {
>> > +                tml->r =(int64_t) strtoll(val, NULL, 10);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar *)"d")) {
>> > +                tml->d = (int64_t)strtoll(val, NULL, 10);
>> > +                rep->fragment_duration = (int64_t) strtoll(val, NULL,
>> 10);
>> > +            }
>> > +            attr = attr->next;
>> > +            xmlFree(val);
>> > +        }
>> > +        dynarray_add(&rep->timelines, &rep->n_timelines, tml);
>> > +    }
>> > +
>> > +    return 0;
>> > +}
>> > +
>> > +static int parse_manifest_representation(AVFormatContext *s, const
>> char *url,
>> > +                                         xmlNodePtr node,
>> > +                                         xmlNodePtr adaptionset_node,
>> > +                                         xmlNodePtr mpd_baseurl_node,
>> > +                                         xmlNodePtr
>> period_baseurl_node,
>> > +                                         xmlNodePtr
>> fragment_template_node,
>> > +                                         xmlNodePtr
>> content_component_node,
>> > +                                         xmlNodePtr
>> adaptionset_baseurl_node)
>> > +{
>> > +    int32_t ret = 0;
>> > +    int32_t audio_rep_idx = 0;
>> > +    int32_t video_rep_idx = 0;
>> > +    char *temp_string = NULL;
>> > +    DASHContext *c = s->priv_data;
>> > +    struct representation *rep = NULL;
>> > +    struct fragment *seg = NULL;
>> > +    xmlNodePtr representation_segmenttemplate_node = NULL;
>> > +    xmlNodePtr representation_baseurl_node = NULL;
>> > +    xmlNodePtr representation_segmentlist_node = NULL;
>> > +    xmlNodePtr fragment_timeline_node = NULL;
>> > +    xmlNodePtr fragment_templates_tab[2];
>> > +    xmlChar *duration_val = NULL;
>> > +    xmlChar *startnumber_val = NULL;
>> > +    xmlChar *timescale_val = NULL;
>> > +    xmlChar *initialization_val = NULL;
>> > +    xmlChar *media_val = NULL;
>> > +    xmlNodePtr baseurl_nodes[4];
>> > +    xmlNodePtr representation_node = node;
>> > +    xmlChar *rep_id_val = xmlGetProp(representation_node, "id");
>> > +    xmlChar *rep_bandwidth_val = xmlGetProp(representation_node,
>> "bandwidth");
>> > +    enum AVMediaType type = AVMEDIA_TYPE_UNKNOWN;
>> > +
>> > +    // try get information from representation
>> > +    if (type == AVMEDIA_TYPE_UNKNOWN)
>> > +        type = get_content_type(representation_node);
>> > +    // try get information from contentComponen
>> > +    if (type == AVMEDIA_TYPE_UNKNOWN)
>> > +        type = get_content_type(content_component_node);
>> > +    // try get information from adaption set
>> > +    if (type == AVMEDIA_TYPE_UNKNOWN)
>> > +        type = get_content_type(adaptionset_node);
>> > +    if (type == AVMEDIA_TYPE_UNKNOWN) {
>> > +        av_log(s, AV_LOG_VERBOSE, "Parsing '%s' - skipp not supported
>> representation type\n", url);
>> > +    } else if ((type == AVMEDIA_TYPE_VIDEO && !c->cur_video) || (type
>> == AVMEDIA_TYPE_AUDIO && !c->cur_audio)) {
>> > +        // convert selected representation to our internal struct
>> > +        rep = av_mallocz(sizeof(struct representation));
>> > +        if (!rep) {
>> > +            ret = AVERROR(ENOMEM);
>> > +            goto end;
>> > +        }
>> > +        representation_segmenttemplate_node =
>> find_child_node_by_name(representation_node, "SegmentTemplate");
>> > +        representation_baseurl_node = find_child_node_by_name(representation_node,
>> "BaseURL");
>> > +        representation_segmentlist_node =
>> find_child_node_by_name(representation_node, "SegmentList");
>> > +        reset_packet(&rep->pkt);
>> > +
>> > +        baseurl_nodes[0] = mpd_baseurl_node;
>> > +        baseurl_nodes[1] = period_baseurl_node;
>> > +        baseurl_nodes[2] = adaptionset_baseurl_node;
>> > +        baseurl_nodes[3] = representation_baseurl_node;
>> > +
>> > +        if (representation_segmenttemplate_node ||
>> fragment_template_node) {
>> > +            fragment_timeline_node = NULL;
>> > +            fragment_templates_tab[0] = representation_segmenttemplate
>> _node;
>> > +            fragment_templates_tab[1] = fragment_template_node;
>> > +
>> > +            duration_val = get_val_from_nodes_tab(fragment_templates_tab,
>> 2, "duration");
>> > +            startnumber_val = get_val_from_nodes_tab(fragment_templates_tab,
>> 2, "startNumber");
>> > +            timescale_val = get_val_from_nodes_tab(fragment_templates_tab,
>> 2, "timescale");
>> > +            initialization_val = get_val_from_nodes_tab(fragment_templates_tab,
>> 2, "initialization");
>> > +            media_val = get_val_from_nodes_tab(fragment_templates_tab,
>> 2, "media");
>> > +
>> > +            if (initialization_val) {
>> > +                rep->init_section = av_mallocz(sizeof(struct
>> fragment));
>> > +                if (!rep->init_section) {
>> > +                    av_free(rep);
>> > +                    ret = AVERROR(ENOMEM);
>> > +                    goto end;
>> > +                }
>> > +                rep->init_section->url =
>> get_content_url(baseurl_nodes, 4, rep_id_val, rep_bandwidth_val,
>> initialization_val);
>> > +                if (!rep->init_section->url) {
>> > +                    av_free(rep->init_section);
>> > +                    av_free(rep);
>> > +                    ret = AVERROR(ENOMEM);
>> > +                    goto end;
>> > +                }
>> > +                rep->init_section->size = -1;
>> > +                xmlFree(initialization_val);
>> > +            }
>> > +
>> > +            if (media_val) {
>> > +                rep->url_template = get_content_url(baseurl_nodes, 4,
>> rep_id_val, rep_bandwidth_val, media_val);
>> > +                temp_string = rep->url_template;
>> > +                if (temp_string) {
>> > +                    if (av_stristr(temp_string, "$Number")) {
>> > +                        rep->tmp_url_type = TMP_URL_TYPE_NUMBER;  /*
>> Number-Based. */
>> > +                    } else if (av_stristr(temp_string, "$Time")) {
>> > +                        rep->tmp_url_type = TMP_URL_TYPE_TIME; /*
>> Time-Based. */
>> > +                    } else {
>> > +                        temp_string = NULL;
>> > +                    }
>> > +                }
>> > +                xmlFree(media_val);
>> > +            }
>> > +            if (duration_val) {
>> > +                rep->fragment_duration = (int64_t)
>> strtoll(duration_val, NULL, 10);
>> > +                xmlFree(duration_val);
>> > +            }
>> > +            if (timescale_val) {
>> > +                rep->fragment_timescale = (int64_t)
>> strtoll(timescale_val, NULL, 10);
>> > +                xmlFree(timescale_val);
>> > +            }
>> > +            if (startnumber_val) {
>> > +                rep->first_seq_no = (int64_t) strtoll(startnumber_val,
>> NULL, 10);
>> > +                xmlFree(startnumber_val);
>> > +            }
>> > +
>> > +            fragment_timeline_node = find_child_node_by_name(representation_segmenttemplate_node,
>> "SegmentTimeline");
>> > +
>> > +            if (!fragment_timeline_node)
>> > +                fragment_timeline_node = find_child_node_by_name(fragment_template_node,
>> "SegmentTimeline");
>> > +            if (fragment_timeline_node) {
>> > +                fragment_timeline_node = xmlFirstElementChild(fragment_
>> timeline_node);
>> > +                while (fragment_timeline_node) {
>> > +                    ret = parse_manifest_segmenttimeline(s, rep,
>> fragment_timeline_node);
>> > +                    if (ret < 0) {
>> > +                        return ret;
>> > +                    }
>> > +                    fragment_timeline_node =
>> xmlNextElementSibling(fragment_timeline_node);
>> > +                }
>> > +            }
>> > +        } else if (representation_baseurl_node &&
>> !representation_segmentlist_node) {
>> > +            seg = av_mallocz(sizeof(struct fragment));
>> > +            if (!seg) {
>> > +                ret = AVERROR(ENOMEM);
>> > +                goto end;
>> > +            }
>> > +            seg->url = get_content_url(baseurl_nodes, 4, rep_id_val,
>> rep_bandwidth_val, NULL);
>> > +            if (!seg->url) {
>> > +                av_free(seg);
>> > +                ret = AVERROR(ENOMEM);
>> > +                goto end;
>> > +            }
>> > +            seg->size = -1;
>> > +            dynarray_add(&rep->fragments, &rep->n_fragments, seg);
>> > +        } else if (!representation_baseurl_node &&
>> representation_segmentlist_node) {
>> > +            // TODO: https://www.brendanlong.com/th
>> e-structure-of-an-mpeg-dash-mpd.html
>> > +            // http://www-itec.uni-klu.ac.at/
>> dash/ddash/mpdGenerator.php?fragmentlength=15&type=full
>> > +            xmlNodePtr fragmenturl_node = NULL;
>> > +            duration_val = xmlGetProp(representation_segmentlist_node,
>> "duration");
>> > +            timescale_val = xmlGetProp(representation_segmentlist_node,
>> "timescale");
>> > +            if (duration_val) {
>> > +                rep->fragment_duration = (int64_t)
>> strtoll(duration_val, NULL, 10);
>> > +                xmlFree(duration_val);
>> > +            }
>> > +            if (timescale_val) {
>> > +                rep->fragment_timescale = (int64_t)
>> strtoll(timescale_val, NULL, 10);
>> > +                xmlFree(timescale_val);
>> > +            }
>> > +            fragmenturl_node = xmlFirstElementChild(represent
>> ation_segmentlist_node);
>> > +            while (fragmenturl_node) {
>> > +                ret = parse_manifest_segmenturlnode(s, rep,
>> fragmenturl_node, baseurl_nodes, rep_id_val, rep_bandwidth_val);
>> > +                if (ret < 0) {
>> > +                    return ret;
>> > +                }
>> > +                fragmenturl_node = xmlNextElementSibling(fragment
>> url_node);
>> > +            }
>> > +        } else {
>> > +            free_representation(rep);
>> > +            rep = NULL;
>> > +            av_log(s, AV_LOG_ERROR, "Unknown format of Representation
>> node id[%s] \n", (const char *)rep_id_val);
>> > +        }
>> > +
>> > +        if (rep) {
>> > +            if (rep->fragment_duration > 0 && !rep->fragment_timescale)
>> > +                rep->fragment_timescale = 1;
>> > +            if (type == AVMEDIA_TYPE_VIDEO) {
>> > +                rep->rep_idx = video_rep_idx;
>> > +                c->cur_video = rep;
>> > +            } else {
>> > +                rep->rep_idx = audio_rep_idx;
>> > +                c->cur_audio = rep;
>> > +            }
>> > +        }
>> > +    }
>> > +
>> > +    video_rep_idx += type == AVMEDIA_TYPE_VIDEO;
>> > +    audio_rep_idx += type == AVMEDIA_TYPE_AUDIO;
>> > +
>> > +end:
>> > +    if (rep_id_val)
>> > +        xmlFree(rep_id_val);
>> > +    if (rep_bandwidth_val)
>> > +        xmlFree(rep_bandwidth_val);
>> > +
>> > +    return ret;
>> > +}
>> > +
>> > +static int parse_manifest_adaptationset(AVFormatContext *s, const
>> char *url, xmlNodePtr adaptionset_node, xmlNodePtr mpd_baseurl_node,
>> xmlNodePtr period_baseurl_node)
>> > +{
>> > +    int ret = 0;
>> > +    xmlNodePtr fragment_template_node = NULL;
>> > +    xmlNodePtr content_component_node = NULL;
>> > +    xmlNodePtr adaptionset_baseurl_node = NULL;
>> > +    xmlNodePtr node = NULL;
>> > +
>> > +    node = xmlFirstElementChild(adaptionset_node);
>> > +    while (node) {
>> > +        if (!xmlStrcmp(node->name, (const xmlChar
>> *)"SegmentTemplate")) {
>> > +            fragment_template_node = node;
>> > +        } else if (!xmlStrcmp(node->name, (const xmlChar
>> *)"ContentComponent")) {
>> > +            content_component_node = node;
>> > +        } else if (!xmlStrcmp(node->name, (const xmlChar *)"BaseURL"))
>> {
>> > +            adaptionset_baseurl_node = node;
>> > +        } else if (!xmlStrcmp(node->name, (const xmlChar
>> *)"Representation")) {
>> > +            ret = parse_manifest_representation(s, url, node,
>> > +                                                adaptionset_node,
>> > +                                                mpd_baseurl_node,
>> > +                                                period_baseurl_node,
>> > +                                                fragment_template_node,
>> > +                                                content_component_node,
>> > +
>> adaptionset_baseurl_node);
>> > +            if (ret < 0) {
>> > +                return ret;
>> > +            }
>> > +        }
>> > +        node = xmlNextElementSibling(node);
>> > +    }
>> > +    return 0;
>> > +}
>> > +
>> > +
>> > +static int parse_manifest(AVFormatContext *s, const char *url,
>> AVIOContext *in)
>> > +{
>> > +    DASHContext *c = s->priv_data;
>> > +    int ret = 0;
>> > +    int close_in = 0;
>> > +    uint8_t *new_url = NULL;
>> > +    int64_t filesize = 0;
>> > +    char *buffer = NULL;
>> > +    AVDictionary *opts = NULL;
>> > +    xmlDoc *doc = NULL;
>> > +    xmlNodePtr root_element = NULL;
>> > +    xmlNodePtr node = NULL;
>> > +    xmlNodePtr period_node = NULL;
>> > +    xmlNodePtr mpd_baseurl_node = NULL;
>> > +    xmlNodePtr period_baseurl_node = NULL;
>> > +    xmlNodePtr adaptionset_node = NULL;
>> > +    xmlAttrPtr attr = NULL;
>> > +    xmlChar *val  = NULL;
>> > +    uint32_t perdiod_duration_sec = 0;
>> > +    uint32_t perdiod_start_sec = 0;
>> > +    int32_t audio_rep_idx = 0;
>> > +    int32_t video_rep_idx = 0;
>> > +
>> > +    if (!in) {
>> > +        close_in = 1;
>> > +        /* This is XML manifest there is no need to set range header */
>> > +        av_dict_set(&opts, "seekable", "0", 0);
>> > +        // broker prior HTTP options that should be consistent across
>> requests
>> > +        av_dict_set(&opts, "user-agent", c->user_agent, 0);
>> > +        av_dict_set(&opts, "cookies", c->cookies, 0);
>> > +        av_dict_set(&opts, "headers", c->headers, 0);
>> > +
>> > +        ret = avio_open2(&in, url, AVIO_FLAG_READ,
>> c->interrupt_callback, &opts);
>> > +        av_dict_free(&opts);
>> > +        if (ret < 0)
>> > +            return ret;
>> > +    }
>> > +
>> > +    if (av_opt_get(in, "location", AV_OPT_SEARCH_CHILDREN, &new_url)
>> >= 0) {
>> > +        c->base_url = av_strdup(new_url);
>> > +    } else {
>> > +        c->base_url = av_strdup(url);
>> > +    }
>> > +
>> > +    filesize = avio_size(in);
>> > +    if (filesize <= 0) {
>> > +        filesize = 8 * 1024;
>> > +    }
>> > +
>> > +    buffer = av_mallocz(filesize);
>> > +    if (!buffer) {
>> > +        return AVERROR(ENOMEM);
>> > +    }
>> > +
>> > +    filesize = avio_read(in, buffer, filesize);
>> > +    if (filesize > 0) {
>> > +        LIBXML_TEST_VERSION
>> > +
>> > +            doc = xmlReadMemory(buffer, filesize, c->base_url, NULL,
>> 0);
>> > +        root_element = xmlDocGetRootElement(doc);
>> > +        node = root_element;
>> > +
>> > +        if (!node) {
>> > +            ret = AVERROR_INVALIDDATA;
>> > +            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - missing
>> root node\n", url);
>> > +            goto cleanup;
>> > +        }
>> > +
>> > +        if (node->type != XML_ELEMENT_NODE ||
>> > +            xmlStrcmp(node->name, (const xmlChar *)"MPD")) {
>> > +            ret = AVERROR_INVALIDDATA;
>> > +            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - wrong root
>> node name[%s] type[%d]\n", url, node->name, (int)node->type);
>> > +            goto cleanup;
>> > +        }
>> > +
>> > +        val = xmlGetProp(node, "type");
>> > +        if (!val) {
>> > +            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - missing
>> type attrib\n", url);
>> > +            ret = AVERROR_INVALIDDATA;
>> > +            goto cleanup;
>> > +        }
>> > +        if (!xmlStrcmp(val, (const xmlChar *)"dynamic"))
>> > +            c->is_live = 1;
>> > +        xmlFree(val);
>> > +
>> > +        attr = node->properties;
>> > +        while (attr) {
>> > +            val = xmlGetProp(node, attr->name);
>> > +
>> > +            if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"availabilityStartTime")) {
>> > +                c->availability_start_time_sec =
>> get_utc_date_time_insec(s, (const char *)val);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"publishTime")) {
>> > +                c->publish_time_sec = get_utc_date_time_insec(s,
>> (const char *)val);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"minimumUpdatePeriod")) {
>> > +                c->minimum_update_period_sec = get_duration_insec(s,
>> (const char *)val);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"timeShiftBufferDepth")) {
>> > +                c->time_shift_buffer_depth_sec = get_duration_insec(s,
>> (const char *)val);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"minBufferTime")) {
>> > +                c->min_buffer_time_sec = get_duration_insec(s, (const
>> char *)val);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"suggestedPresentationDelay")) {
>> > +                c->suggested_presentation_delay_sec =
>> get_duration_insec(s, (const char *)val);
>> > +            } else if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"mediaPresentationDuration")) {
>> > +                c->media_presentation_duration_sec =
>> get_duration_insec(s, (const char *)val);
>> > +            }
>> > +            attr = attr->next;
>> > +            xmlFree(val);
>> > +        }
>> > +
>> > +        mpd_baseurl_node = find_child_node_by_name(node, "BaseURL");
>> > +
>> > +        // at now we can handle only one period, with the longest
>> duration
>> > +        node = xmlFirstElementChild(node);
>> > +        while (node) {
>> > +            if (!xmlStrcmp(node->name, (const xmlChar *)"Period")) {
>> > +                perdiod_duration_sec = 0;
>> > +                perdiod_start_sec = 0;
>> > +                attr = node->properties;
>> > +                while (attr) {
>> > +                    val = xmlGetProp(node, attr->name);
>> > +                    if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"duration")) {
>> > +                        perdiod_duration_sec = get_duration_insec(s,
>> (const char *)val);
>> > +                    } else if (!xmlStrcmp(attr->name, (const xmlChar
>> *)"start")) {
>> > +                        perdiod_start_sec = get_duration_insec(s,
>> (const char *)val);
>> > +                    }
>> > +                    attr = attr->next;
>> > +                    xmlFree(val);
>> > +                }
>> > +                if ((perdiod_duration_sec) >=
>> (c->period_duration_sec)) {
>> > +                    period_node = node;
>> > +                    c->period_duration_sec = perdiod_duration_sec;
>> > +                    c->period_start_sec = perdiod_start_sec;
>> > +                    if (c->period_start_sec > 0)
>> > +                        c->media_presentation_duration_sec =
>> c->period_duration_sec;
>> > +                }
>> > +            }
>> > +            node = xmlNextElementSibling(node);
>> > +        }
>> > +        if (!period_node) {
>> > +            av_log(s, AV_LOG_ERROR, "Unable to parse '%s' - missing
>> Period node\n", url);
>> > +            ret = AVERROR_INVALIDDATA;
>> > +            goto cleanup;
>> > +        }
>> > +        // explore AdaptationSet
>> > +        adaptionset_node = xmlFirstElementChild(period_node);
>> > +        while (adaptionset_node) {
>> > +            if (!xmlStrcmp(adaptionset_node->name, (const xmlChar
>> *)"BaseURL")) {
>> > +                period_baseurl_node = adaptionset_node;
>> > +            } else if (!xmlStrcmp(adaptionset_node->name, (const
>> xmlChar *)"AdaptationSet")) {
>> > +                parse_manifest_adaptationset(s, url,
>> adaptionset_node, mpd_baseurl_node, period_baseurl_node);
>> > +            }
>> > +            adaptionset_node = xmlNextElementSibling(adaption
>> set_node);
>> > +        }
>> > +        if (c->cur_video) {
>> > +            c->cur_video->rep_count = video_rep_idx;
>> > +            c->cur_video->fix_multiple_stsd_order = 1;
>> > +            av_log(s, AV_LOG_VERBOSE, "rep_idx[%d]\n",
>> (int)c->cur_video->rep_idx);
>> > +            av_log(s, AV_LOG_VERBOSE, "rep_count[%d]\n",
>> (int)video_rep_idx);
>> > +        }
>> > +        if (c->cur_audio) {
>> > +            c->cur_audio->rep_count = audio_rep_idx;
>> > +        }
>> > +
>> > +cleanup:
>> > +        /*free the document */
>> > +        xmlFreeDoc(doc);
>> > +        xmlCleanupParser();
>> > +    } else {
>> > +        av_log(s, AV_LOG_ERROR, "Unable to read to offset '%s'\n",
>> url);
>> > +        ret = AVERROR_INVALIDDATA;
>> > +    }
>> > +
>> > +    av_free(new_url);
>> > +    av_free(buffer);
>> > +    if (close_in) {
>> > +        avio_close(in);
>> > +    }
>> > +    return ret;
>> > +}
>> > +
>> > +static int64_t calc_cur_seg_no(AVFormatContext *s, struct
>> representation *pls)
>> > +{
>> > +    DASHContext *c = pls->parent->priv_data;
>> > +    int64_t num = 0;
>> > +
>> > +    if (c->is_live) {
>> > +        if (!pls->fragment_duration) {
>> > +            av_log(s, AV_LOG_ERROR, "Get not get fragment duration
>> value in live mode\n");
>> > +            return pls->first_seq_no;
>> > +        }
>> > +        num = pls->first_seq_no + (((get_current_time_in_sec() -
>> c->availability_start_time_sec) - c->presentation_delay_sec) *
>> pls->fragment_timescale) / pls->fragment_duration;
>> > +    } else {
>> > +        num = pls->first_seq_no;
>> > +    }
>> > +    return num;
>> > +}
>> > +
>> > +static int64_t calc_min_seg_no(AVFormatContext *s, struct
>> representation *pls)
>> > +{
>> > +    DASHContext *c = pls->parent->priv_data;
>> > +    int64_t num = 0;
>> > +
>> > +    if (c->is_live) {
>> > +        if (!pls->fragment_duration) {
>> > +            av_log(s, AV_LOG_ERROR, "Get not get fragment duration
>> value in live mode\n");
>> > +            return pls->first_seq_no;
>> > +        }
>> > +        num = pls->first_seq_no + (((get_current_time_in_sec() -
>> c->availability_start_time_sec) - c->time_shift_buffer_depth_sec) *
>> pls->fragment_timescale)  / pls->fragment_duration;
>> > +    } else {
>> > +        num = pls->first_seq_no;
>> > +    }
>> > +    return num;
>> > +}
>> > +
>> > +static int64_t calc_max_seg_no(AVFormatContext *s, struct
>> representation *pls)
>> > +{
>> > +    DASHContext *c = pls->parent->priv_data;
>> > +    int64_t num = 0;
>> > +    int64_t i = 0;
>> > +
>> > +    if (c->is_live) {
>> > +        if (!pls->fragment_duration) {
>> > +            av_log(s, AV_LOG_ERROR, "Get not get fragment duration
>> value in live mode\n");
>> > +            return pls->first_seq_no;
>> > +        }
>> > +        num = pls->first_seq_no + (((get_current_time_in_sec() -
>> c->availability_start_time_sec)) * pls->fragment_timescale)  /
>> pls->fragment_duration;
>> > +    } else {
>> > +        if (pls->n_fragments) {
>> > +            num = pls->first_seq_no + pls->n_fragments - 1;
>> > +        } else if (pls->n_timelines) {
>> > +            num = pls->first_seq_no + pls->n_timelines - 1;
>> > +            for (i = 0; i < pls->n_timelines; ++i) {
>> > +                num += pls->timelines[i]->r;
>> > +            }
>> > +        } else {
>> > +            num = pls->first_seq_no + (c->media_presentation_duration_sec
>> * pls->fragment_timescale) / pls->fragment_duration;
>> > +        }
>> > +    }
>> > +
>> > +    return num;
>> > +}
>> > +
>> > +static int64_t get_fragment_start_time(struct representation *pls,
>> int64_t cur_seq_no)
>> > +{
>> > +    int64_t i = 0;
>> > +    int64_t j = 0;
>> > +    int64_t num = 0;
>> > +    int64_t startTime = 0;
>> > +
>> > +    if (pls->n_timelines) {
>> > +        for (i = 0; i < pls->n_timelines; ++i) {
>> > +            if (pls->timelines[i]->t > 0) {
>> > +                startTime = pls->timelines[i]->t;
>> > +            }
>> > +            if (num == cur_seq_no)
>> > +                goto finish;
>> > +            startTime += pls->timelines[i]->d;
>> > +            for (j = 0; j < pls->timelines[i]->r; ++j) {
>> > +                num++;
>> > +                if (num == cur_seq_no)
>> > +                    goto finish;
>> > +                startTime += pls->timelines[i]->d;
>> > +            }
>> > +            num++;
>> > +        }
>> > +    }
>> > +
>> > +finish:
>> > +    return startTime;
>> > +}
>> > +
>> > +static struct fragment *get_current_fragment(struct representation
>> *pls)
>> > +{
>> > +    int64_t tmp_val = 0;
>> > +    int64_t min_seq_no = 0;
>> > +    int64_t max_seq_no = 0;
>> > +    char buffer[1024];
>> > +    char *tmp_str = NULL;
>> > +    struct fragment *seg = NULL;
>> > +    struct fragment *seg_ptr = NULL;
>> > +    DASHContext *c = pls->parent->priv_data;
>> > +
>> > +    if (pls->n_fragments > 0) {
>> > +        if (pls->cur_seq_no < pls->n_fragments) {
>> > +            seg_ptr = pls->fragments[pls->cur_seq_no];
>> > +            seg = av_mallocz(sizeof(struct fragment));
>> > +            if (!seg) {
>> > +                return NULL;
>> > +            }
>> > +            seg->url = av_strdup(seg_ptr->url);
>> > +            if (!seg->url) {
>> > +                av_free(seg);
>> > +                return NULL;
>> > +            }
>> > +            seg->size = seg_ptr->size;
>> > +            seg->url_offset = seg_ptr->url_offset;
>> > +            return seg;
>> > +        }
>> > +    }
>> > +    if (c->is_live) {
>> > +        while (1) {
>> > +            min_seq_no = calc_min_seg_no(pls->parent, pls);
>> > +            max_seq_no = calc_max_seg_no(pls->parent, pls);
>> > +
>> > +            if (pls->cur_seq_no <= min_seq_no) {
>> > +                av_log(pls->parent, AV_LOG_VERBOSE, "old fragment:
>> cur[%"PRId64"] min[%"PRId64"] max[%"PRId64"], playlist %d\n",
>> > +                       (int64_t)pls->cur_seq_no, min_seq_no,
>> max_seq_no, (int)pls->rep_idx);
>> > +                pls->cur_seq_no = calc_cur_seg_no(pls->parent, pls);
>> > +            } else if (pls->cur_seq_no > max_seq_no) {
>> > +                av_log(pls->parent, AV_LOG_VERBOSE, "new fragment:
>> min[%"PRId64"] max[%"PRId64"], playlist %d\n",
>> > +                       min_seq_no, max_seq_no, (int)pls->rep_idx);
>> > +                av_usleep(1000);
>> > +                continue;
>> > +            }
>> > +            break;
>> > +        }
>> > +        seg = av_mallocz(sizeof(struct fragment));
>> > +        if (!seg) {
>> > +            return NULL;
>> > +        }
>> > +    } else if (pls->cur_seq_no <= pls->last_seq_no) {
>> > +        seg = av_mallocz(sizeof(struct fragment));
>> > +        if (!seg) {
>> > +            return NULL;
>> > +        }
>> > +    }
>> > +    if (seg) {
>> > +        if (pls->tmp_url_type != TMP_URL_TYPE_UNSPECIFIED) {
>> > +            tmp_val = pls->tmp_url_type == TMP_URL_TYPE_NUMBER ?
>> pls->cur_seq_no : get_fragment_start_time(pls, pls->cur_seq_no);
>> > +            if (av_get_frame_filename(buffer, sizeof(buffer),
>> pls->url_template, (int64_t)tmp_val) < 0) {
>> > +                av_log(pls->parent, AV_LOG_ERROR, "Invalid segment
>> filename template %s\n", pls->url_template);
>> > +                return NULL;
>> > +            }
>> > +
>> > +            if (pls->tmp_url_type == TMP_URL_TYPE_NUMBER) {
>> > +                tmp_str = replace_template_str(buffer, "$Number$");
>> > +            } else if (pls->tmp_url_type == TMP_URL_TYPE_TIME) {
>> > +                tmp_str = replace_template_str(buffer, "$Time$");
>> > +            } else {
>> > +                av_log(pls->parent, AV_LOG_ERROR, "Invalid
>> tmp_url_type\n");
>> > +                return NULL;
>> > +            }
>> > +
>> > +            seg->url = av_strdup(tmp_str);
>> > +            if (!seg->url) {
>> > +                av_free(tmp_str);
>> > +                return NULL;
>> > +            }
>> > +        } else {
>> > +            av_log(pls->parent, AV_LOG_ERROR, "Unable to unable to
>> resolve template url '%s'\n", pls->url_template);
>> > +            seg->url = av_strdup(pls->url_template);
>> > +            if (!seg->url) {
>> > +                return NULL;
>> > +            }
>> > +        }
>> > +        seg->size = -1;
>> > +    }
>> > +
>> > +    av_free(tmp_str);
>> > +    return seg;
>> > +}
>> > +
>> > +enum ReadFromURLMode {
>> > +    READ_NORMAL,
>> > +    READ_COMPLETE,
>> > +};
>> > +
>> > +static int read_from_url(struct representation *pls, struct fragment
>> *seg,
>> > +                         uint8_t *buf, int buf_size,
>> > +                         enum ReadFromURLMode mode)
>> > +{
>> > +    int ret;
>> > +
>> > +    /* limit read if the fragment was only a part of a file */
>> > +    if (seg->size >= 0)
>> > +        buf_size = FFMIN(buf_size, pls->cur_seg_size -
>> pls->cur_seg_offset);
>> > +
>> > +    if (mode == READ_COMPLETE) {
>> > +        ret = avio_read(pls->input, buf, buf_size);
>> > +        if (ret < buf_size) {
>> > +            av_log(pls->parent, AV_LOG_WARNING, "Could not read
>> complete fragment.\n");
>> > +        }
>> > +    } else {
>> > +        ret = avio_read(pls->input, buf, buf_size);
>> > +    }
>> > +    if (ret > 0)
>> > +        pls->cur_seg_offset += ret;
>> > +
>> > +    return ret;
>> > +}
>> > +
>> > +static int open_input(DASHContext *c, struct representation *pls,
>> struct fragment *seg)
>> > +{
>> > +    AVDictionary *opts = NULL;
>> > +    char url[MAX_URL_SIZE];
>> > +    int ret;
>> > +
>> > +    // broker prior HTTP options that should be consistent across
>> requests
>> > +    av_dict_set(&opts, "user-agent", c->user_agent, 0);
>> > +    av_dict_set(&opts, "cookies", c->cookies, 0);
>> > +    av_dict_set(&opts, "headers", c->headers, 0);
>> > +    if (c->is_live) {
>> > +        av_dict_set(&opts, "seekable", "0", 0);
>> > +    }
>> > +
>> > +    if (seg->size >= 0) {
>> > +        /* try to restrict the HTTP request to the part we want
>> > +         * (if this is in fact a HTTP request) */
>> > +        av_dict_set_int(&opts, "offset", seg->url_offset, 0);
>> > +        av_dict_set_int(&opts, "end_offset", seg->url_offset +
>> seg->size, 0);
>> > +    }
>> > +
>> > +    ff_make_absolute_url(url, MAX_URL_SIZE, c->base_url, seg->url);
>> > +    av_log(pls->parent, AV_LOG_VERBOSE, "DASH request for url '%s',
>> offset %"PRId64", playlist %d\n",
>> > +           url, seg->url_offset, pls->rep_idx);
>> > +    ret = open_url(pls->parent, &pls->input, url, c->avio_opts, opts,
>> NULL);
>> > +    if (ret < 0) {
>> > +        goto cleanup;
>> > +    }
>> > +
>> > +    /* Seek to the requested position. If this was a HTTP request, the
>> offset
>> > +     * should already be where want it to, but this allows e.g. local
>> testing
>> > +     * without a HTTP server. */
>> > +    if (!ret && seg->url_offset) {
>> > +        int64_t seekret = avio_seek(pls->input, seg->url_offset,
>> SEEK_SET);
>> > +        if (seekret < 0) {
>> > +            av_log(pls->parent, AV_LOG_ERROR, "Unable to seek to
>> offset %"PRId64" of DASH fragment '%s'\n", seg->url_offset, seg->url);
>> > +            ret = (int) seekret;
>> > +            ff_format_io_close(pls->parent, &pls->input);
>> > +        }
>> > +    }
>> > +
>> > +cleanup:
>> > +    av_dict_free(&opts);
>> > +    pls->cur_seg_offset = 0;
>> > +    pls->cur_seg_size = seg->size;
>> > +    return ret;
>> > +}
>> > +
>> > +static int update_init_section(struct representation *pls)
>> > +{
>> > +    static const int max_init_section_size = 1024*1024;
>> > +    DASHContext *c = pls->parent->priv_data;
>> > +    int64_t sec_size = 0;
>> > +    int64_t urlsize = 0;
>> > +    int ret = 0;
>> > +
>> > +    /* read init section only once per representation */
>> > +    if (!pls->init_section || pls->init_sec_buf) {
>> > +        return 0;
>> > +    }
>> > +
>> > +    ret = open_input(c, pls, pls->init_section);
>> > +    if (ret < 0) {
>> > +        av_log(pls->parent, AV_LOG_WARNING, "Failed to open an
>> initialization section in playlist %d\n", pls->rep_idx);
>> > +        return ret;
>> > +    }
>> > +
>> > +    if (pls->init_section->size >= 0) {
>> > +        sec_size = pls->init_section->size;
>> > +    } else if ((urlsize = avio_size(pls->input)) >= 0) {
>> > +        sec_size = urlsize;
>> > +    } else {
>> > +        sec_size = max_init_section_size;
>> > +    }
>> > +    av_log(pls->parent, AV_LOG_DEBUG, "Downloading an initialization
>> section of size %"PRId64"\n", sec_size);
>> > +    sec_size = FFMIN(sec_size, max_init_section_size);
>> > +    av_fast_malloc(&pls->init_sec_buf, &pls->init_sec_buf_size,
>> sec_size);
>> > +    ret = read_from_url(pls, pls->init_section, pls->init_sec_buf,
>> pls->init_sec_buf_size, READ_COMPLETE);
>> > +    ff_format_io_close(pls->parent, &pls->input);
>> > +    if (ret < 0)
>> > +        return ret;
>> > +
>> > +    if (pls->fix_multiple_stsd_order && pls->rep_idx > 0) {
>> > +        uint8_t **stsd_entries = NULL;
>> > +        int *stsd_entries_size = NULL;
>> > +        int i = 4;
>> > +
>> > +        while (i <= (ret - 4)) {
>> > +            // find start stsd atom
>> > +            if (!memcmp(pls->init_sec_buf + i, "stsd", 4)) {
>> > +                /* 1B version
>> > +                 * 3B flags
>> > +                 * 4B num of entries */
>> > +                int stsd_first_offset = i + 8;
>> > +                int stsd_offset = 0;
>> > +                int j = 0;
>> > +                uint32_t stsd_count = AV_RB32(pls->init_sec_buf +
>> stsd_first_offset);
>> > +                stsd_first_offset += 4;
>> > +                if (stsd_count != pls->rep_count) {
>> > +                    i++;
>> > +                    continue;
>> > +                }
>> > +                // find all stsd entries
>> > +                stsd_entries = av_mallocz_array(stsd_count,
>> sizeof(*stsd_entries));
>> > +                stsd_entries_size = av_mallocz_array(stsd_count,
>> sizeof(*stsd_entries_size));
>> > +                for (j = 0; j < stsd_count; ++j) {
>> > +                    /* 4B - size
>> > +                     * 4B - format */
>> > +                    stsd_entries_size[j] = AV_RB32(pls->init_sec_buf +
>> stsd_first_offset + stsd_offset);
>> > +                    stsd_entries[j] = av_malloc(stsd_entries_size[j]);
>> > +                    memcpy(stsd_entries[j], pls->init_sec_buf +
>> stsd_first_offset + stsd_offset, stsd_entries_size[j]);
>> > +                    stsd_offset += stsd_entries_size[j];
>> > +                }
>> > +                // reorder stsd entries
>> > +                // as first put stsd entry for current representation
>> > +                j = pls->rep_idx;
>> > +                stsd_offset = stsd_first_offset;
>> > +                memcpy(pls->init_sec_buf + stsd_offset,
>> stsd_entries[j], stsd_entries_size[j]);
>> > +                stsd_offset += stsd_entries_size[j];
>> > +                for (j = 0; j < stsd_count; ++j) {
>> > +                    if (j != pls->rep_idx) {
>> > +                        memcpy(pls->init_sec_buf + stsd_offset,
>> stsd_entries[j], stsd_entries_size[j]);
>> > +                        stsd_offset += stsd_entries_size[j];
>> > +                    }
>> > +                    av_free(stsd_entries[j]);
>> > +                }
>> > +                av_freep(&stsd_entries);
>> > +                av_freep(&stsd_entries_size);
>> > +                break;
>> > +            }
>> > +            i++;
>> > +        }
>> > +    }
>> > +
>> > +    av_log(pls->parent, AV_LOG_TRACE, "pls[%p] init section
>> size[%d]\n", pls, (int)ret);
>> > +    pls->init_sec_data_len = ret;
>> > +    pls->init_sec_buf_read_offset = 0;
>> > +
>> > +    return 0;
>> > +}
>> > +
>> > +static int64_t seek_data(void *opaque, int64_t offset, int whence)
>> > +{
>> > +    struct representation *v = opaque;
>> > +    if (v->n_fragments && !v->init_sec_data_len) {
>> > +        return avio_seek(v->input, offset, whence);
>> > +    }
>> > +
>> > +    return AVERROR(ENOSYS);
>> > +}
>> > +
>> > +static int read_data(void *opaque, uint8_t *buf, int buf_size)
>> > +{
>> > +    int ret = 0;
>> > +    struct representation *v = opaque;
>> > +    DASHContext *c = v->parent->priv_data;
>> > +
>> > +restart:
>> > +    if (!v->input) {
>> > +        free_fragment(&v->cur_seg);
>> > +        v->cur_seg = get_current_fragment(v);
>> > +        if (!v->cur_seg) {
>> > +            ret = AVERROR_EOF;
>> > +            goto end;
>> > +        }
>> > +
>> > +        /* load/update Media Initialization Section, if any */
>> > +        ret = update_init_section(v);
>> > +        if (ret)
>> > +            goto end;
>> > +
>> > +        ret = open_input(c, v, v->cur_seg);
>> > +        if (ret < 0) {
>> > +            if (ff_check_interrupt(c->interrupt_callback)) {
>> > +                goto end;
>> > +                ret = AVERROR_EXIT;
>> > +            }
>> > +            av_log(v->parent, AV_LOG_WARNING, "Failed to open fragment
>> of playlist %d\n", v->rep_idx);
>> > +            v->cur_seq_no++;
>> > +            goto restart;
>> > +        }
>> > +    }
>> > +
>> > +    if (v->init_sec_buf_read_offset < v->init_sec_data_len) {
>> > +        /* Push init section out first before first actual fragment */
>> > +        int copy_size = FFMIN(v->init_sec_data_len -
>> v->init_sec_buf_read_offset, buf_size);
>> > +        memcpy(buf, v->init_sec_buf, copy_size);
>> > +        v->init_sec_buf_read_offset += copy_size;
>> > +        ret = copy_size;
>> > +        goto end;
>> > +    }
>> > +
>> > +    /* check the v->cur_seg, if it is null, get current and double
>> check if the new v->cur_seg*/
>> > +    if (!v->cur_seg) {
>> > +        v->cur_seg = get_current_fragment(v);
>> > +    }
>> > +    if (!v->cur_seg) {
>> > +        ret = AVERROR_EOF;
>> > +        goto end;
>> > +    }
>> > +    ret = read_from_url(v, v->cur_seg, buf, buf_size, READ_NORMAL);
>> > +    if (ret > 0)
>> > +        goto end;
>> > +    ff_format_io_close(v->parent, &v->input);
>> > +    v->cur_seq_no++;
>> > +    goto restart;
>> > +
>> > +end:
>> > +    return ret;
>> > +}
>> > +
>> > +static int save_avio_options(AVFormatContext *s)
>> > +{
>> > +    DASHContext *c = s->priv_data;
>> > +    const char *opts[] = { "headers", "user_agent", "user-agent",
>> "cookies", NULL }, **opt = opts;
>> > +    uint8_t *buf = NULL;
>> > +    int ret = 0;
>> > +
>> > +    while (*opt) {
>> > +        if (av_opt_get(s->pb, *opt, AV_OPT_SEARCH_CHILDREN, &buf) >=
>> 0) {
>> > +            if (buf) {
>> > +                ret = av_dict_set(&c->avio_opts, *opt, buf,
>> AV_DICT_DONT_STRDUP_VAL);
>> > +                if (ret < 0)
>> > +                    return ret;
>> > +            }
>> > +        }
>> > +        opt++;
>> > +    }
>> > +
>> > +    return ret;
>> > +}
>> > +
>> > +static int nested_io_open(AVFormatContext *s, AVIOContext **pb, const
>> char *url,
>> > +                          int flags, AVDictionary **opts)
>> > +{
>> > +    av_log(s, AV_LOG_ERROR,
>> > +           "A HDS playlist item '%s' referred to an external file
>> '%s'. "
>> > +           "Opening this file was forbidden for security reasons\n",
>> > +           s->filename, url);
>> > +    return AVERROR(EPERM);
>> > +}
>> > +
>> > +static int reopen_demux_for_component(AVFormatContext *s, struct
>> representation *pls)
>> > +{
>> > +    DASHContext *c = s->priv_data;
>> > +    AVInputFormat *in_fmt = NULL;
>> > +    AVDictionary  *in_fmt_opts = NULL;
>> > +    uint8_t *avio_ctx_buffer  = NULL;
>> > +    int ret = 0;
>> > +
>> > +    if (pls->ctx) {
>> > +        /* note: the internal buffer could have changed, and be !=
>> avio_ctx_buffer */
>> > +        av_freep(&pls->pb.buffer);
>> > +        memset(&pls->pb, 0x00, sizeof(AVIOContext));
>> > +        pls->ctx->pb = NULL;
>> > +        avformat_close_input(&pls->ctx);
>> > +        pls->ctx = NULL;
>> > +    }
>> > +    if (!(pls->ctx = avformat_alloc_context())) {
>> > +        ret = AVERROR(ENOMEM);
>> > +        goto fail;
>> > +    }
>> > +
>> > +    avio_ctx_buffer  = av_malloc(INITIAL_BUFFER_SIZE);
>> > +    if (!avio_ctx_buffer ) {
>> > +        ret = AVERROR(ENOMEM);
>> > +        avformat_free_context(pls->ctx);
>> > +        pls->ctx = NULL;
>> > +        goto fail;
>> > +    }
>> > +    if (c->is_live) {
>> > +        ffio_init_context(&pls->pb, avio_ctx_buffer ,
>> INITIAL_BUFFER_SIZE, 0, pls, read_data, NULL, NULL);
>> > +    } else {
>> > +        ffio_init_context(&pls->pb, avio_ctx_buffer ,
>> INITIAL_BUFFER_SIZE, 0, pls, read_data, NULL, seek_data);
>> > +    }
>> > +    pls->pb.seekable = 0;
>> > +
>> > +    if ((ret = ff_copy_whiteblacklists(pls->ctx, s)) < 0)
>> > +        goto fail;
>> > +
>> > +    pls->ctx->flags = AVFMT_FLAG_CUSTOM_IO;
>> > +    pls->ctx->probesize = 1024 * 4;
>> > +    pls->ctx->max_analyze_duration = 4 * AV_TIME_BASE;
>> > +    ret = av_probe_input_buffer(&pls->pb, &in_fmt, "", NULL, 0, 0);
>> > +    if (ret < 0) {
>> > +        av_log(s, AV_LOG_ERROR, "Error when loading first fragment,
>> playlist %d\n", (int)pls->rep_idx);
>> > +        avformat_free_context(pls->ctx);
>> > +        pls->ctx = NULL;
>> > +        goto fail;
>> > +    }
>> > +
>> > +    pls->ctx->pb = &pls->pb;
>> > +    pls->ctx->io_open  = nested_io_open;
>> > +
>> > +    // provide additional information from mpd if available
>> > +    ret = avformat_open_input(&pls->ctx, "", in_fmt, &in_fmt_opts);
>> //pls->init_section->url
>> > +    av_dict_free(&in_fmt_opts);
>> > +    if (ret < 0)
>> > +        goto fail;
>> > +    if (pls->n_fragments) {
>> > +        ret = avformat_find_stream_info(pls->ctx, NULL);
>> > +        if (ret < 0)
>> > +            goto fail;
>> > +    }
>> > +
>> > +fail:
>> > +    return ret;
>> > +}
>> > +
>> > +static int open_demux_for_component(AVFormatContext *s, struct
>> representation *pls)
>> > +{
>> > +    int ret = 0;
>> > +    int i;
>> > +
>> > +    pls->parent = s;
>> > +    pls->cur_seq_no  = calc_cur_seg_no(s, pls);
>> > +    pls->last_seq_no = calc_max_seg_no(s, pls);
>> > +
>> > +    ret = reopen_demux_for_component(s, pls);
>> > +    if (ret < 0) {
>> > +        goto fail;
>> > +    }
>> > +    for (i = 0; i < pls->ctx->nb_streams; i++) {
>> > +        AVStream *st = avformat_new_stream(s, NULL);
>> > +        AVStream *ist = pls->ctx->streams[i];
>> > +        if (!st) {
>> > +            ret = AVERROR(ENOMEM);
>> > +            goto fail;
>> > +        }
>> > +        st->id = i;
>> > +        avcodec_parameters_copy(st->codecpar,
>> pls->ctx->streams[i]->codecpar);
>> > +        avpriv_set_pts_info(st, ist->pts_wrap_bits,
>> ist->time_base.num, ist->time_base.den);
>> > +    }
>> > +
>> > +    return 0;
>> > +fail:
>> > +    return ret;
>> > +}
>> > +
>> > +static int dash_read_header(AVFormatContext *s)
>> > +{
>> > +    void *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb;
>> > +    DASHContext *c = s->priv_data;
>> > +    int ret = 0;
>> > +    int stream_index = 0;
>> > +
>> > +    c->interrupt_callback = &s->interrupt_callback;
>> > +    // if the URL context is good, read important options we must
>> broker later
>> > +    if (u) {
>> > +        update_options(&c->user_agent, "user-agent", u);
>> > +        update_options(&c->cookies, "cookies", u);
>> > +        update_options(&c->headers, "headers", u);
>> > +    }
>> > +
>> > +    if ((ret = parse_manifest(s, s->filename, s->pb)) < 0)
>> > +        goto fail;
>> > +
>> > +    if ((ret = save_avio_options(s)) < 0)
>> > +        goto fail;
>> > +
>> > +    /* If this isn't a live stream, fill the total duration of the
>> > +     * stream. */
>> > +    if (!c->is_live) {
>> > +        s->duration = (int64_t) c->media_presentation_duration_sec *
>> AV_TIME_BASE;
>> > +    }
>> > +
>> > +    /* Open the demuxer for curent video and current audio components
>> if available */
>> > +    if (!ret && c->cur_video) {
>> > +        ret = open_demux_for_component(s, c->cur_video);
>> > +        if (!ret) {
>> > +            c->cur_video->stream_index = stream_index;
>> > +            ++stream_index;
>> > +        } else {
>> > +            free_representation(c->cur_video);
>> > +            c->cur_video = NULL;
>> > +        }
>> > +    }
>> > +
>> > +    if (!ret && c->cur_audio) {
>> > +        ret = open_demux_for_component(s, c->cur_audio);
>> > +        if (!ret) {
>> > +            c->cur_audio->stream_index = stream_index;
>> > +            ++stream_index;
>> > +        } else {
>> > +            free_representation(c->cur_audio);
>> > +            c->cur_audio = NULL;
>> > +        }
>> > +    }
>> > +
>> > +    if (!stream_index) {
>> > +        ret = AVERROR_INVALIDDATA;
>> > +        goto fail;
>> > +    }
>> > +
>> > +    /* Create a program */
>> > +    if (!ret) {
>> > +        AVProgram *program;
>> > +        program = av_new_program(s, 0);
>> > +        if (!program) {
>> > +            goto fail;
>> > +        }
>> > +
>> > +        if (c->cur_video) {
>> > +            av_program_add_stream_index(s, 0,
>> c->cur_video->stream_index);
>> > +        }
>> > +
>> > +        if (c->cur_audio) {
>> > +            av_program_add_stream_index(s, 0,
>> c->cur_audio->stream_index);
>> > +        }
>> > +    }
>> > +
>> > +    return 0;
>> > +fail:
>> > +    return ret;
>> > +}
>> > +
>> > +static int dash_read_packet(AVFormatContext *s, AVPacket *pkt)
>> > +{
>> > +    DASHContext *c = s->priv_data;
>> > +    int ret = 0;
>> > +    struct representation *cur = NULL;
>> > +
>> > +    if (!c->cur_audio && !c->cur_video) {
>> > +        return AVERROR_INVALIDDATA;
>> > +    }
>> > +    if (c->cur_audio && !c->cur_video) {
>> > +        cur = c->cur_audio;
>> > +    } else if (!c->cur_audio && c->cur_video) {
>> > +        cur = c->cur_video;
>> > +    } else if (c->cur_video->cur_timestamp <
>> c->cur_audio->cur_timestamp) {
>> > +        cur = c->cur_video;
>> > +    } else {
>> > +        cur = c->cur_audio;
>> > +    }
>> > +
>> > +    if (cur->ctx) {
>> > +        ret = av_read_frame(cur->ctx, &cur->pkt);
>> > +        if (ret < 0) {
>> > +            av_packet_unref(&cur->pkt);
>> > +        } else {
>> > +            /* If we got a packet, return it */
>> > +            *pkt = cur->pkt;
>> > +            cur->cur_timestamp = av_rescale(pkt->pts,
>> (int64_t)cur->ctx->streams[0]->time_base.num * 90000,
>> cur->ctx->streams[0]->time_base.den);
>> > +            pkt->stream_index = cur->stream_index;
>> > +            reset_packet(&cur->pkt);
>> > +            return 0;
>> > +        }
>> > +    }
>> > +    return AVERROR_EOF;
>> > +}
>> > +
>> > +static int dash_close(AVFormatContext *s)
>> > +{
>> > +    DASHContext *c = s->priv_data;
>> > +
>> > +    if (c->cur_audio) {
>> > +        free_representation(c->cur_audio);
>> > +    }
>> > +
>> > +    if (c->cur_video) {
>> > +        free_representation(c->cur_video);
>> > +    }
>> > +
>> > +    av_freep(&c->cookies);
>> > +    av_freep(&c->user_agent);
>> > +    av_dict_free(&c->avio_opts);
>> > +    av_freep(&c->base_url);
>> > +    return 0;
>> > +}
>> > +
>> > +static int dash_seek(AVFormatContext *s, struct representation *pls,
>> int64_t seek_pos_msec, int flags)
>> > +{
>> > +    int ret = 0;
>> > +    int i = 0;
>> > +    int j = 0;
>> > +    int64_t duration = 0;
>> > +
>> > +    av_log(pls->parent, AV_LOG_VERBOSE, "DASH seek pos[%"PRId64"ms],
>> playlist %d\n", seek_pos_msec, pls->rep_idx);
>> > +
>> > +    // single fragment mode
>> > +    if (pls->n_fragments) {
>> > +        pls->cur_timestamp = 0;
>> > +        pls->cur_seg_offset = 0;
>> > +        ff_read_frame_flush(pls->ctx);
>> > +        return av_seek_frame(pls->ctx, -1, seek_pos_msec*1000, flags);
>> > +    }
>> > +
>> > +    if (pls->input)
>> > +        ff_format_io_close(pls->parent, &pls->input);
>> > +
>> > +    // find the nearest fragment
>> > +    if (pls->n_timelines > 0 && pls->fragment_timescale > 0) {
>> > +        int64_t num = pls->first_seq_no;
>> > +        av_log(pls->parent, AV_LOG_VERBOSE, "dash_seek with
>> SegmentTimeline start n_timelines[%d] last_seq_no[%"PRId64"], playlist
>> %d.\n",
>> > +               (int)pls->n_timelines, (int64_t)pls->last_seq_no,
>> (int)pls->rep_idx);
>> > +        for (i = 0; i < pls->n_timelines; i++) {
>> > +            if (pls->timelines[i]->t > 0) {
>> > +                duration = pls->timelines[i]->t;
>> > +            }
>> > +            duration += pls->timelines[i]->d;
>> > +            if (seek_pos_msec < ((duration * 1000) /
>> pls->fragment_timescale)) {
>> > +                goto set_seq_num;
>> > +            }
>> > +            for (j = 0; j < pls->timelines[i]->r; j++) {
>> > +                duration += pls->timelines[i]->d;
>> > +                num++;
>> > +                if (seek_pos_msec < ((duration * 1000) /
>> pls->fragment_timescale)) {
>> > +                    goto set_seq_num;
>> > +                }
>> > +            }
>> > +            num++;
>> > +        }
>> > +
>> > +set_seq_num:
>> > +        pls->cur_seq_no = num > pls->last_seq_no ? pls->last_seq_no :
>> num;
>> > +        av_log(pls->parent, AV_LOG_VERBOSE, "dash_seek with
>> SegmentTimeline end cur_seq_no[%"PRId64"], playlist %d.\n",
>> > +               (int64_t)pls->cur_seq_no, (int)pls->rep_idx);
>> > +    } else if (pls->fragment_duration > 0) {
>> > +        pls->cur_seq_no = pls->first_seq_no + ((seek_pos_msec *
>> pls->fragment_timescale) / pls->fragment_duration) / 1000;
>> > +    } else {
>> > +        av_log(pls->parent, AV_LOG_ERROR, "dash_seek missing
>> fragment_duration\n");
>> > +        pls->cur_seq_no = pls->first_seq_no;
>> > +    }
>> > +    pls->cur_timestamp = 0;
>> > +    pls->cur_seg_offset = 0;
>> > +    pls->init_sec_buf_read_offset = 0;
>> > +    ret = reopen_demux_for_component(s, pls);
>> > +
>> > +    return ret;
>> > +}
>> > +
>> > +static int dash_read_seek(AVFormatContext *s, int stream_index,
>> int64_t timestamp, int flags)
>> > +{
>> > +    int ret = 0;
>> > +    DASHContext *c = s->priv_data;
>> > +    int64_t seek_pos_msec = av_rescale_rnd(timestamp, 1000,
>> > +
>>  s->streams[stream_index]->time_base.den,
>> > +                                           flags &
>> AVSEEK_FLAG_BACKWARD ?
>> > +                                           AV_ROUND_DOWN :
>> AV_ROUND_UP);
>> > +    if ((flags & AVSEEK_FLAG_BYTE) || c->is_live)
>> > +        return AVERROR(ENOSYS);
>> > +    if (c->cur_audio) {
>> > +        ret = dash_seek(s, c->cur_audio, seek_pos_msec, flags);
>> > +    }
>> > +    if (!ret && c->cur_video) {
>> > +        ret = dash_seek(s, c->cur_video, seek_pos_msec, flags);
>> > +    }
>> > +    return ret;
>> > +}
>> > +
>> > +static int dash_probe(AVProbeData *p)
>> > +{
>> > +    if (!av_stristr(p->buf, "<MPD"))
>> > +        return 0;
>> > +
>> > +    if (av_stristr(p->buf, "dash:profile:isoff-on-demand:2011") ||
>> > +        av_stristr(p->buf, "dash:profile:isoff-live:2011") ||
>> > +        av_stristr(p->buf, "dash:profile:isoff-live:2012") ||
>> > +        av_stristr(p->buf, "dash:profile:isoff-main:2011")) {
>> > +        return AVPROBE_SCORE_MAX;
>> > +    }
>> > +    if (av_stristr(p->buf, "dash:profile")) {
>> > +        return AVPROBE_SCORE_MAX >> 1;
>> > +    }
>> > +
>> > +    return 0;
>> > +}
>> > +
>> > +#define OFFSET(x) offsetof(DASHContext, x)
>> > +#define FLAGS AV_OPT_FLAG_DECODING_PARAM
>> > +static const AVOption dash_options[] = {
>> > +    {NULL}
>> > +};
>> > +
>> > +static const AVClass dash_class = {
>> > +    .class_name = "dash",
>> > +    .item_name  = av_default_item_name,
>> > +    .option     = dash_options,
>> > +    .version    = LIBAVUTIL_VERSION_INT,
>> > +};
>> > +
>> > +AVInputFormat ff_dash_demuxer = {
>> > +    .name           = "dash",
>> > +    .long_name      = NULL_IF_CONFIG_SMALL("Dynamic Adaptive Streaming
>> over HTTP"),
>> > +    .priv_class     = &dash_class,
>> > +    .priv_data_size = sizeof(DASHContext),
>> > +    .read_probe     = dash_probe,
>> > +    .read_header    = dash_read_header,
>> > +    .read_packet    = dash_read_packet,
>> > +    .read_close     = dash_close,
>> > +    .read_seek      = dash_read_seek,
>> > +    .flags          = AVFMT_NO_BYTE_SEEK,
>> > +};
>>
>> You seem to have a relatively clean separation between parsing the
>> manifest, its memory representation, and using it. It would probably be
>> good if you could move the parsing code to a separate source file, to
>> make the whole thing more readable. (That's just a suggestion.)
>>
> Yes, this is a base version, and i will optimizing the code readability if
> the patch can applied into ffmpeg :)
>
>>
>> Also, I hope that strreplace function was the only case where you
>> copied something from somewhere else without attribution and checking
>> the license.
>>
>> Can't comment on the DASH mechanics.
>>
>> (I don't know if these things came up in earlier review.)
>> _______________________________________________
>> ffmpeg-devel mailing list
>> ffmpeg-devel at ffmpeg.org
>> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>>
>
>


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