Sounds good :D I have incorporated the changes and resubmitted the patch - http://ffmpeg.org/pipermail/ffmpeg-devel/2020-November/272964.html
Please review. Thanks, Vignesh On Thu, Nov 26, 2020 at 12:37 PM Steven Liu <l...@chinaffmpeg.org> wrote: > > > > 2020年11月26日 下午12:43，Vignesh Ravichandran < > vignesh.ravichandra...@gmail.com> 写道： > > > > This check may not be enough. The below values would pass the check > which should not be the case: > > 20-11-26T08:34:00.000 > > 2020-11-26T8:34:00.000 > > 2020-11-26T08:60:00.000 > > 2020-11-26T08:60:0.000 > > 2020-13-26T08:34:00.000 > > > > The regex check approach mentioned earlier checks: > > 1. The value is in "YYYY-MM-DDThh:mm:ss.SSS" format ( > https://tools.ietf.org/html/draft-pantos-http-live-streaming-23#section-4.3.2.6 > ) > > 2. The values for YYYY, MM, DD, hh, mm, ss, SSS are valid. For example: > the check would fail for MM = 00 > > 1st split by T > 2nd split by - > 3rd split by : > 4th the last value is double > > And check the value :D > > What about this? > > > > On Thu, Nov 26, 2020 at 8:00 AM Steven Liu <l...@chinaffmpeg.org> wrote: > > > > > > > 2020年11月25日 下午9:57，Vignesh Ravichandran < > vignesh.ravichandra...@gmail.com> 写道： > > > > > > Sure, how about the snippet below: > > > > > > regex_t regex; > > > regcomp(®ex, > > > > "([12][0-9]{3}-(0[1-9]|1[0-2])-(0[1-9]|[12][0-9]|3[01])T([01][1-9]|2[0-3]):([0-5][0-9]):([0-5][0-9]).([0-9]{3}))", > > > REG_EXTENDED); > > > if (regexec(®ex, ptr, 0, NULL, 0) == REG_NOMATCH) { > > > ret = AVERROR_INVALIDDATA; > > > goto fail; > > > } > > > > Define a new function to check the value: > > 1. Split the string by ‘-‘ > > 2. Check every value splited by ‘-‘ > > 3. If the value is int, that is correct result. > > 4. Else not. > > > > > > On Wed, Nov 25, 2020 at 5:31 PM Steven Liu <l...@chinaffmpeg.org> wrote: > > > > > >> > > >> > > >>> 2020年11月25日 下午7:49，Vignesh Ravichandran < > > >> vignesh.ravichandra...@gmail.com> 写道： > > >>> > > >>> We could add a simple check like below to prevent it: > > >>> > > >>> if (sscanf(ptr, "%d-%d-%dT%d:%d:%d.%lf", &y, &M, &d, &h, &m, &s, > &ms) != > > >> 7) > > >>> { > > >>> ret = AVERROR_INVALIDDATA; > > >>> goto fail; > > >>> } > > >>> > > >>> Please let me know. > > >> Not sure this is better way, what about validate the string of the > > >> "#EXT-X-PROGRAM-DATE-TIME” values？ > > >>> > > >>> > > >>> Thanks, > > >>> Vignesh > > >>> > > >>> On Wed, Nov 25, 2020 at 11:29 AM Steven Liu <l...@chinaffmpeg.org> > wrote: > > >>> > > >>>> > > >>>> > > >>>>> 2020年11月25日 下午1:16，Vignesh Ravichandran < > > >>>> vignesh.ravichandra...@gmail.com> 写道： > > >>>>> > > >>>>> Bug ID: 8989 > > >>>>> > > >>>>> This is is due to the following behavior in the current code: > > >>>>> 1. The initial_prog_date_time gets set to the current local time > > >>>>> 2. The existing playlist (.m3u8) file gets parsed and the segments > > >>>> present are added to the variant stream > > >>>>> 3. The new segment is created and added > > >>>>> 4. The existing segments and the new segment are written to the > > >> playlist > > >>>> file. The initial_prog_date_time from point 1 is used for > calculating > > >>>> "#EXT-X-PROGRAM-DATE-TIME" for the segments, which results in > incorrect > > >>>> "#EXT-X-PROGRAM-DATE-TIME" values for existing segments > > >>>>> > > >>>>> The following approach fixes this bug: > > >>>>> 1. Add a new variable "discont_program_date_time" of type double to > > >>>> HLSSegment struct > > >>>>> 2. Store the "EXT-X-PROGRAM-DATE-TIME" value from the existing > segments > > >>>> in this variable > > >>>>> 3. When writing to playlist file if "discont_program_date_time" is > set, > > >>>> then use that value for "EXT-X-PROGRAM-DATE-TIME" else use the value > > >>>> present in vs->initial_prog_date_time > > >>>>> > > >>>>> Signed-off-by: Vignesh Ravichandran < > vignesh.ravichandra...@gmail.com> > > >>>>> --- > > >>>>> libavformat/hlsenc.c | 35 +++++++++++++++++++++++++++++++---- > > >>>>> 1 file changed, 31 insertions(+), 4 deletions(-) > > >>>>> > > >>>>> diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c > > >>>>> index cbfd8f7c0d..030a2d3b97 100644 > > >>>>> --- a/libavformat/hlsenc.c > > >>>>> +++ b/libavformat/hlsenc.c > > >>>>> @@ -88,6 +88,7 @@ typedef struct HLSSegment { > > >>>>> char iv_string[KEYSIZE*2 + 1]; > > >>>>> > > >>>>> struct HLSSegment *next; > > >>>>> + double discont_program_date_time; > > >>>>> } HLSSegment; > > >>>>> > > >>>>> typedef enum HLSFlags { > > >>>>> @@ -1124,6 +1125,7 @@ static int hls_append_segment(struct > > >>>> AVFormatContext *s, HLSContext *hls, > > >>>>> en->keyframe_size = vs->video_keyframe_size; > > >>>>> en->next = NULL; > > >>>>> en->discont = 0; > > >>>>> + en->discont_program_date_time = 0; > > >>>>> > > >>>>> if (vs->discontinuity) { > > >>>>> en->discont = 1; > > >>>>> @@ -1148,7 +1150,8 @@ static int hls_append_segment(struct > > >>>> AVFormatContext *s, HLSContext *hls, > > >>>>> > > >>>>> if (hls->max_nb_segments && vs->nb_entries >= > hls->max_nb_segments) > > >> { > > >>>>> en = vs->segments; > > >>>>> - vs->initial_prog_date_time += en->duration; > > >>>>> + if (!en->next->discont_program_date_time && > > >>>> !en->discont_program_date_time) > > >>>>> + vs->initial_prog_date_time += en->duration; > > >>>>> vs->segments = en->next; > > >>>>> if (en && hls->flags & HLS_DELETE_SEGMENTS && > > >>>>> #if FF_API_HLS_WRAP > > >>>>> @@ -1182,6 +1185,8 @@ static int parse_playlist(AVFormatContext *s, > > >>>> const char *url, VariantStream *vs > > >>>>> char line[MAX_URL_SIZE]; > > >>>>> const char *ptr; > > >>>>> const char *end; > > >>>>> + int is_discont_detected = 0; > > >>>>> + double discont_program_date_time = 0; > > >>>>> > > >>>>> if ((ret = ffio_open_whitelist(&in, url, AVIO_FLAG_READ, > > >>>>> &s->interrupt_callback, NULL, > > >>>>> @@ -1211,6 +1216,7 @@ static int parse_playlist(AVFormatContext *s, > > >>>> const char *url, VariantStream *vs > > >>>>> } else if (av_strstart(line, "#EXT-X-DISCONTINUITY", &ptr)) { > > >>>>> is_segment = 1; > > >>>>> vs->discontinuity = 1; > > >>>>> + is_discont_detected = 1; > > >>>>> } else if (av_strstart(line, "#EXTINF:", &ptr)) { > > >>>>> is_segment = 1; > > >>>>> vs->duration = atof(ptr); > > >>>>> @@ -1236,7 +1242,23 @@ static int parse_playlist(AVFormatContext > *s, > > >>>> const char *url, VariantStream *vs > > >>>>> av_strlcpy(vs->iv_string, ptr, > > >>>> sizeof(vs->iv_string)); > > >>>>> } > > >>>>> } > > >>>>> - > > >>>>> + } else if (av_strstart(line, "#EXT-X-PROGRAM-DATE-TIME:", > > >> &ptr) > > >>>> && is_discont_detected) { > > >>>>> + struct tm program_date_time; > > >>>>> + int y,M,d,h,m,s; > > >>>>> + double ms; > > >>>>> + sscanf(ptr, "%d-%d-%dT%d:%d:%d.%lf", &y, &M, &d, &h, > &m, > > >>>> &s, &ms); > > >>>> What will happen if I modify the value of “EXT-X-PROGRAM-DATE-TIME” > by > > >>>> hacker, > > >>>> For example: > > >>>> #EXT-X-PROGRAM-DATA-TIME: good-morning-ladies-and-gentlemen. > > >>>> > > >>>>> + > > >>>>> + program_date_time.tm_year = y - 1900; > > >>>>> + program_date_time.tm_mon = M - 1; > > >>>>> + program_date_time.tm_mday = d; > > >>>>> + program_date_time.tm_hour = h; > > >>>>> + program_date_time.tm_min = m; > > >>>>> + program_date_time.tm_sec = s; > > >>>>> + program_date_time.tm_isdst = -1; > > >>>>> + > > >>>>> + discont_program_date_time = > mktime(&program_date_time); > > >>>>> + discont_program_date_time += (double)(ms / 1000); > > >>>>> + is_discont_detected = 0; > > >>>>> } else if (av_strstart(line, "#", NULL)) { > > >>>>> continue; > > >>>>> } else if (line[0]) { > > >>>>> @@ -1250,8 +1272,9 @@ static int parse_playlist(AVFormatContext *s, > > >>>> const char *url, VariantStream *vs > > >>>>> 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); > > >>>>> + vs->last_segment->discont_program_date_time = > > >>>> discont_program_date_time; > > >>>>> + discont_program_date_time += vs->duration; > > >>>>> if (ret < 0) > > >>>>> goto fail; > > >>>>> vs->start_pos = new_start_pos; > > >>>>> @@ -1572,7 +1595,11 @@ static int hls_window(AVFormatContext *s, > int > > >>>> last, VariantStream *vs) > > >>>>> 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); > > >>>>> + en->filename, > > >>>>> + > en->discont_program_date_time ? > > >>>> &en->discont_program_date_time : prog_date_time_p, > > >>>>> + en->keyframe_size, > > >>>> en->keyframe_pos, hls->flags & HLS_I_FRAMES_ONLY); > > >>>>> + if (en->discont_program_date_time) > > >>>>> + en->discont_program_date_time -= en->duration; > > >>>>> if (ret < 0) { > > >>>>> av_log(s, AV_LOG_WARNING, "ff_hls_write_file_entry get > > >>>> error\n"); > > >>>>> } > > >>>>> -- > > >>>>> 2.24.2 (Apple Git-127) > > >>>>> > > >>>>> _______________________________________________ > > >>>>> ffmpeg-devel mailing list > > >>>>> ffmpeg-devel@ffmpeg.org > > >>>>> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > >>>>> > > >>>>> To unsubscribe, visit link above, or email > > >>>>> ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > > >>>> > > >>>> Thanks > > >>>> > > >>>> Steven Liu > > >>>> > > >>>> > > >>>> > > >>>> > > >>> _______________________________________________ > > >>> ffmpeg-devel mailing list > > >>> ffmpeg-devel@ffmpeg.org > > >>> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > >>> > > >>> To unsubscribe, visit link above, or email > > >>> ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > > >> > > >> Thanks > > >> > > >> Steven Liu > > >> > > >> > > >> > > >> _______________________________________________ > > >> ffmpeg-devel mailing list > > >> ffmpeg-devel@ffmpeg.org > > >> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > >> > > >> To unsubscribe, visit link above, or email > > >> ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > > > _______________________________________________ > > > ffmpeg-devel mailing list > > > ffmpeg-devel@ffmpeg.org > > > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > > > > > To unsubscribe, visit link above, or email > > > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > > > > Thanks > > > > Steven Liu > > > > > > > > _______________________________________________ > > ffmpeg-devel mailing list > > ffmpeg-devel@ffmpeg.org > > https://ffmpeg.org/mailman/listinfo/ffmpeg-devel > > > > To unsubscribe, visit link above, or email > > ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe". > > Thanks > > Steven Liu > > > > _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".
