yading@11: /*
yading@11:  * "NUT" Container Format demuxer
yading@11:  * Copyright (c) 2004-2006 Michael Niedermayer
yading@11:  * Copyright (c) 2003 Alex Beregszaszi
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include "libavutil/avstring.h"
yading@11: #include "libavutil/avassert.h"
yading@11: #include "libavutil/bswap.h"
yading@11: #include "libavutil/dict.h"
yading@11: #include "libavutil/mathematics.h"
yading@11: #include "libavutil/tree.h"
yading@11: #include "avio_internal.h"
yading@11: #include "nut.h"
yading@11: #include "riff.h"
yading@11: 
yading@11: #define NUT_MAX_STREAMS 256    /* arbitrary sanity check value */
yading@11: 
yading@11: static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
yading@11:                                   int64_t *pos_arg, int64_t pos_limit);
yading@11: 
yading@11: static int get_str(AVIOContext *bc, char *string, unsigned int maxlen)
yading@11: {
yading@11:     unsigned int len = ffio_read_varlen(bc);
yading@11: 
yading@11:     if (len && maxlen)
yading@11:         avio_read(bc, string, FFMIN(len, maxlen));
yading@11:     while (len > maxlen) {
yading@11:         avio_r8(bc);
yading@11:         len--;
yading@11:     }
yading@11: 
yading@11:     if (maxlen)
yading@11:         string[FFMIN(len, maxlen - 1)] = 0;
yading@11: 
yading@11:     if (maxlen == len)
yading@11:         return -1;
yading@11:     else
yading@11:         return 0;
yading@11: }
yading@11: 
yading@11: static int64_t get_s(AVIOContext *bc)
yading@11: {
yading@11:     int64_t v = ffio_read_varlen(bc) + 1;
yading@11: 
yading@11:     if (v & 1)
yading@11:         return -(v >> 1);
yading@11:     else
yading@11:         return  (v >> 1);
yading@11: }
yading@11: 
yading@11: static uint64_t get_fourcc(AVIOContext *bc)
yading@11: {
yading@11:     unsigned int len = ffio_read_varlen(bc);
yading@11: 
yading@11:     if (len == 2)
yading@11:         return avio_rl16(bc);
yading@11:     else if (len == 4)
yading@11:         return avio_rl32(bc);
yading@11:     else {
yading@11:         av_log(NULL, AV_LOG_ERROR, "Unsupported fourcc length %d\n", len);
yading@11:         return -1;
yading@11:     }
yading@11: }
yading@11: 
yading@11: #ifdef TRACE
yading@11: static inline uint64_t get_v_trace(AVIOContext *bc, const char *file,
yading@11:                                    const char *func, int line)
yading@11: {
yading@11:     uint64_t v = ffio_read_varlen(bc);
yading@11: 
yading@11:     av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n",
yading@11:            v, v, file, func, line);
yading@11:     return v;
yading@11: }
yading@11: 
yading@11: static inline int64_t get_s_trace(AVIOContext *bc, const char *file,
yading@11:                                   const char *func, int line)
yading@11: {
yading@11:     int64_t v = get_s(bc);
yading@11: 
yading@11:     av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n",
yading@11:            v, v, file, func, line);
yading@11:     return v;
yading@11: }
yading@11: 
yading@11: static inline uint64_t get_4cc_trace(AVIOContext *bc, char *file,
yading@11:                                     char *func, int line)
yading@11: {
yading@11:     uint64_t v = get_fourcc(bc);
yading@11: 
yading@11:     av_log(NULL, AV_LOG_DEBUG, "get_fourcc %5"PRId64" / %"PRIX64" in %s %s:%d\n",
yading@11:            v, v, file, func, line);
yading@11:     return v;
yading@11: }
yading@11: #define ffio_read_varlen(bc) get_v_trace(bc,  __FILE__, __PRETTY_FUNCTION__, __LINE__)
yading@11: #define get_s(bc)            get_s_trace(bc,  __FILE__, __PRETTY_FUNCTION__, __LINE__)
yading@11: #define get_fourcc(bc)       get_4cc_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
yading@11: #endif
yading@11: 
yading@11: static int get_packetheader(NUTContext *nut, AVIOContext *bc,
yading@11:                             int calculate_checksum, uint64_t startcode)
yading@11: {
yading@11:     int64_t size;
yading@11: //    start = avio_tell(bc) - 8;
yading@11: 
yading@11:     startcode = av_be2ne64(startcode);
yading@11:     startcode = ff_crc04C11DB7_update(0, (uint8_t*) &startcode, 8);
yading@11: 
yading@11:     ffio_init_checksum(bc, ff_crc04C11DB7_update, startcode);
yading@11:     size = ffio_read_varlen(bc);
yading@11:     if (size > 4096)
yading@11:         avio_rb32(bc);
yading@11:     if (ffio_get_checksum(bc) && size > 4096)
yading@11:         return -1;
yading@11: 
yading@11:     ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
yading@11: 
yading@11:     return size;
yading@11: }
yading@11: 
yading@11: static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos)
yading@11: {
yading@11:     uint64_t state = 0;
yading@11: 
yading@11:     if (pos >= 0)
yading@11:         /* Note, this may fail if the stream is not seekable, but that should
yading@11:          * not matter, as in this case we simply start where we currently are */
yading@11:         avio_seek(bc, pos, SEEK_SET);
yading@11:     while (!url_feof(bc)) {
yading@11:         state = (state << 8) | avio_r8(bc);
yading@11:         if ((state >> 56) != 'N')
yading@11:             continue;
yading@11:         switch (state) {
yading@11:         case MAIN_STARTCODE:
yading@11:         case STREAM_STARTCODE:
yading@11:         case SYNCPOINT_STARTCODE:
yading@11:         case INFO_STARTCODE:
yading@11:         case INDEX_STARTCODE:
yading@11:             return state;
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: /**
yading@11:  * Find the given startcode.
yading@11:  * @param code the startcode
yading@11:  * @param pos the start position of the search, or -1 if the current position
yading@11:  * @return the position of the startcode or -1 if not found
yading@11:  */
yading@11: static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos)
yading@11: {
yading@11:     for (;;) {
yading@11:         uint64_t startcode = find_any_startcode(bc, pos);
yading@11:         if (startcode == code)
yading@11:             return avio_tell(bc) - 8;
yading@11:         else if (startcode == 0)
yading@11:             return -1;
yading@11:         pos = -1;
yading@11:     }
yading@11: }
yading@11: 
yading@11: static int nut_probe(AVProbeData *p)
yading@11: {
yading@11:     int i;
yading@11:     uint64_t code = 0;
yading@11: 
yading@11:     for (i = 0; i < p->buf_size; i++) {
yading@11:         code = (code << 8) | p->buf[i];
yading@11:         if (code == MAIN_STARTCODE)
yading@11:             return AVPROBE_SCORE_MAX;
yading@11:     }
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: #define GET_V(dst, check)                                                     \
yading@11:     do {                                                                      \
yading@11:         tmp = ffio_read_varlen(bc);                                           \
yading@11:         if (!(check)) {                                                       \
yading@11:             av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);  \
yading@11:             return -1;                                                        \
yading@11:         }                                                                     \
yading@11:         dst = tmp;                                                            \
yading@11:     } while (0)
yading@11: 
yading@11: static int skip_reserved(AVIOContext *bc, int64_t pos)
yading@11: {
yading@11:     pos -= avio_tell(bc);
yading@11:     if (pos < 0) {
yading@11:         avio_seek(bc, pos, SEEK_CUR);
yading@11:         return -1;
yading@11:     } else {
yading@11:         while (pos--)
yading@11:             avio_r8(bc);
yading@11:         return 0;
yading@11:     }
yading@11: }
yading@11: 
yading@11: static int decode_main_header(NUTContext *nut)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     AVIOContext *bc    = s->pb;
yading@11:     uint64_t tmp, end;
yading@11:     unsigned int stream_count;
yading@11:     int i, j, count;
yading@11:     int tmp_stream, tmp_mul, tmp_pts, tmp_size, tmp_res, tmp_head_idx;
yading@11: 
yading@11:     end  = get_packetheader(nut, bc, 1, MAIN_STARTCODE);
yading@11:     end += avio_tell(bc);
yading@11: 
yading@11:     GET_V(tmp, tmp >= 2 && tmp <= 3);
yading@11:     GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS);
yading@11: 
yading@11:     nut->max_distance = ffio_read_varlen(bc);
yading@11:     if (nut->max_distance > 65536) {
yading@11:         av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
yading@11:         nut->max_distance = 65536;
yading@11:     }
yading@11: 
yading@11:     GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational));
yading@11:     nut->time_base = av_malloc(nut->time_base_count * sizeof(AVRational));
yading@11: 
yading@11:     for (i = 0; i < nut->time_base_count; i++) {
yading@11:         GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
yading@11:         GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
yading@11:         if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
yading@11:             av_log(s, AV_LOG_ERROR, "time base invalid\n");
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         }
yading@11:     }
yading@11:     tmp_pts      = 0;
yading@11:     tmp_mul      = 1;
yading@11:     tmp_stream   = 0;
yading@11:     tmp_head_idx = 0;
yading@11:     for (i = 0; i < 256;) {
yading@11:         int tmp_flags  = ffio_read_varlen(bc);
yading@11:         int tmp_fields = ffio_read_varlen(bc);
yading@11: 
yading@11:         if (tmp_fields > 0)
yading@11:             tmp_pts = get_s(bc);
yading@11:         if (tmp_fields > 1)
yading@11:             tmp_mul = ffio_read_varlen(bc);
yading@11:         if (tmp_fields > 2)
yading@11:             tmp_stream = ffio_read_varlen(bc);
yading@11:         if (tmp_fields > 3)
yading@11:             tmp_size = ffio_read_varlen(bc);
yading@11:         else
yading@11:             tmp_size = 0;
yading@11:         if (tmp_fields > 4)
yading@11:             tmp_res = ffio_read_varlen(bc);
yading@11:         else
yading@11:             tmp_res = 0;
yading@11:         if (tmp_fields > 5)
yading@11:             count = ffio_read_varlen(bc);
yading@11:         else
yading@11:             count = tmp_mul - tmp_size;
yading@11:         if (tmp_fields > 6)
yading@11:             get_s(bc);
yading@11:         if (tmp_fields > 7)
yading@11:             tmp_head_idx = ffio_read_varlen(bc);
yading@11: 
yading@11:         while (tmp_fields-- > 8)
yading@11:             ffio_read_varlen(bc);
yading@11: 
yading@11:         if (count == 0 || i + count > 256) {
yading@11:             av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         }
yading@11:         if (tmp_stream >= stream_count) {
yading@11:             av_log(s, AV_LOG_ERROR, "illegal stream number\n");
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         }
yading@11: 
yading@11:         for (j = 0; j < count; j++, i++) {
yading@11:             if (i == 'N') {
yading@11:                 nut->frame_code[i].flags = FLAG_INVALID;
yading@11:                 j--;
yading@11:                 continue;
yading@11:             }
yading@11:             nut->frame_code[i].flags          = tmp_flags;
yading@11:             nut->frame_code[i].pts_delta      = tmp_pts;
yading@11:             nut->frame_code[i].stream_id      = tmp_stream;
yading@11:             nut->frame_code[i].size_mul       = tmp_mul;
yading@11:             nut->frame_code[i].size_lsb       = tmp_size + j;
yading@11:             nut->frame_code[i].reserved_count = tmp_res;
yading@11:             nut->frame_code[i].header_idx     = tmp_head_idx;
yading@11:         }
yading@11:     }
yading@11:     av_assert0(nut->frame_code['N'].flags == FLAG_INVALID);
yading@11: 
yading@11:     if (end > avio_tell(bc) + 4) {
yading@11:         int rem = 1024;
yading@11:         GET_V(nut->header_count, tmp < 128U);
yading@11:         nut->header_count++;
yading@11:         for (i = 1; i < nut->header_count; i++) {
yading@11:             uint8_t *hdr;
yading@11:             GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
yading@11:             rem -= nut->header_len[i];
yading@11:             if (rem < 0) {
yading@11:                 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             }
yading@11:             hdr = av_malloc(nut->header_len[i]);
yading@11:             if (!hdr)
yading@11:                 return AVERROR(ENOMEM);
yading@11:             avio_read(bc, hdr, nut->header_len[i]);
yading@11:             nut->header[i] = hdr;
yading@11:         }
yading@11:         av_assert0(nut->header_len[0] == 0);
yading@11:     }
yading@11: 
yading@11:     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
yading@11:         av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
yading@11:         return AVERROR_INVALIDDATA;
yading@11:     }
yading@11: 
yading@11:     nut->stream = av_mallocz(sizeof(StreamContext) * stream_count);
yading@11:     for (i = 0; i < stream_count; i++)
yading@11:         avformat_new_stream(s, NULL);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int decode_stream_header(NUTContext *nut)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     AVIOContext *bc    = s->pb;
yading@11:     StreamContext *stc;
yading@11:     int class, stream_id;
yading@11:     uint64_t tmp, end;
yading@11:     AVStream *st;
yading@11: 
yading@11:     end  = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
yading@11:     end += avio_tell(bc);
yading@11: 
yading@11:     GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
yading@11:     stc = &nut->stream[stream_id];
yading@11:     st  = s->streams[stream_id];
yading@11:     if (!st)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     class                = ffio_read_varlen(bc);
yading@11:     tmp                  = get_fourcc(bc);
yading@11:     st->codec->codec_tag = tmp;
yading@11:     switch (class) {
yading@11:     case 0:
yading@11:         st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
yading@11:         st->codec->codec_id   = av_codec_get_id((const AVCodecTag * const []) {
yading@11:                                                     ff_nut_video_tags,
yading@11:                                                     ff_codec_bmp_tags,
yading@11:                                                     0
yading@11:                                                 },
yading@11:                                                 tmp);
yading@11:         break;
yading@11:     case 1:
yading@11:         st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
yading@11:         st->codec->codec_id   = av_codec_get_id((const AVCodecTag * const []) {
yading@11:                                                     ff_nut_audio_tags,
yading@11:                                                     ff_codec_wav_tags,
yading@11:                                                     0
yading@11:                                                 },
yading@11:                                                 tmp);
yading@11:         break;
yading@11:     case 2:
yading@11:         st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
yading@11:         st->codec->codec_id   = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
yading@11:         break;
yading@11:     case 3:
yading@11:         st->codec->codec_type = AVMEDIA_TYPE_DATA;
yading@11:         st->codec->codec_id   = ff_codec_get_id(ff_nut_data_tags, tmp);
yading@11:         break;
yading@11:     default:
yading@11:         av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
yading@11:         return -1;
yading@11:     }
yading@11:     if (class < 3 && st->codec->codec_id == AV_CODEC_ID_NONE)
yading@11:         av_log(s, AV_LOG_ERROR,
yading@11:                "Unknown codec tag '0x%04x' for stream number %d\n",
yading@11:                (unsigned int) tmp, stream_id);
yading@11: 
yading@11:     GET_V(stc->time_base_id, tmp < nut->time_base_count);
yading@11:     GET_V(stc->msb_pts_shift, tmp < 16);
yading@11:     stc->max_pts_distance = ffio_read_varlen(bc);
yading@11:     GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
yading@11:     st->codec->has_b_frames = stc->decode_delay;
yading@11:     ffio_read_varlen(bc); // stream flags
yading@11: 
yading@11:     GET_V(st->codec->extradata_size, tmp < (1 << 30));
yading@11:     if (st->codec->extradata_size) {
yading@11:         st->codec->extradata = av_mallocz(st->codec->extradata_size +
yading@11:                                           FF_INPUT_BUFFER_PADDING_SIZE);
yading@11:         avio_read(bc, st->codec->extradata, st->codec->extradata_size);
yading@11:     }
yading@11: 
yading@11:     if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
yading@11:         GET_V(st->codec->width,  tmp > 0);
yading@11:         GET_V(st->codec->height, tmp > 0);
yading@11:         st->sample_aspect_ratio.num = ffio_read_varlen(bc);
yading@11:         st->sample_aspect_ratio.den = ffio_read_varlen(bc);
yading@11:         if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
yading@11:             av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
yading@11:                    st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
yading@11:             return -1;
yading@11:         }
yading@11:         ffio_read_varlen(bc); /* csp type */
yading@11:     } else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO) {
yading@11:         GET_V(st->codec->sample_rate, tmp > 0);
yading@11:         ffio_read_varlen(bc); // samplerate_den
yading@11:         GET_V(st->codec->channels, tmp > 0);
yading@11:     }
yading@11:     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
yading@11:         av_log(s, AV_LOG_ERROR,
yading@11:                "stream header %d checksum mismatch\n", stream_id);
yading@11:         return -1;
yading@11:     }
yading@11:     stc->time_base = &nut->time_base[stc->time_base_id];
yading@11:     avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
yading@11:                         stc->time_base->den);
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static void set_disposition_bits(AVFormatContext *avf, char *value,
yading@11:                                  int stream_id)
yading@11: {
yading@11:     int flag = 0, i;
yading@11: 
yading@11:     for (i = 0; ff_nut_dispositions[i].flag; ++i)
yading@11:         if (!strcmp(ff_nut_dispositions[i].str, value))
yading@11:             flag = ff_nut_dispositions[i].flag;
yading@11:     if (!flag)
yading@11:         av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
yading@11:     for (i = 0; i < avf->nb_streams; ++i)
yading@11:         if (stream_id == i || stream_id == -1)
yading@11:             avf->streams[i]->disposition |= flag;
yading@11: }
yading@11: 
yading@11: static int decode_info_header(NUTContext *nut)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     AVIOContext *bc    = s->pb;
yading@11:     uint64_t tmp, chapter_start, chapter_len;
yading@11:     unsigned int stream_id_plus1, count;
yading@11:     int chapter_id, i;
yading@11:     int64_t value, end;
yading@11:     char name[256], str_value[1024], type_str[256];
yading@11:     const char *type;
yading@11:     AVChapter *chapter      = NULL;
yading@11:     AVStream *st            = NULL;
yading@11:     AVDictionary **metadata = NULL;
yading@11: 
yading@11:     end  = get_packetheader(nut, bc, 1, INFO_STARTCODE);
yading@11:     end += avio_tell(bc);
yading@11: 
yading@11:     GET_V(stream_id_plus1, tmp <= s->nb_streams);
yading@11:     chapter_id    = get_s(bc);
yading@11:     chapter_start = ffio_read_varlen(bc);
yading@11:     chapter_len   = ffio_read_varlen(bc);
yading@11:     count         = ffio_read_varlen(bc);
yading@11: 
yading@11:     if (chapter_id && !stream_id_plus1) {
yading@11:         int64_t start = chapter_start / nut->time_base_count;
yading@11:         chapter = avpriv_new_chapter(s, chapter_id,
yading@11:                                      nut->time_base[chapter_start %
yading@11:                                                     nut->time_base_count],
yading@11:                                      start, start + chapter_len, NULL);
yading@11:         metadata = &chapter->metadata;
yading@11:     } else if (stream_id_plus1) {
yading@11:         st       = s->streams[stream_id_plus1 - 1];
yading@11:         metadata = &st->metadata;
yading@11:     } else
yading@11:         metadata = &s->metadata;
yading@11: 
yading@11:     for (i = 0; i < count; i++) {
yading@11:         get_str(bc, name, sizeof(name));
yading@11:         value = get_s(bc);
yading@11:         if (value == -1) {
yading@11:             type = "UTF-8";
yading@11:             get_str(bc, str_value, sizeof(str_value));
yading@11:         } else if (value == -2) {
yading@11:             get_str(bc, type_str, sizeof(type_str));
yading@11:             type = type_str;
yading@11:             get_str(bc, str_value, sizeof(str_value));
yading@11:         } else if (value == -3) {
yading@11:             type  = "s";
yading@11:             value = get_s(bc);
yading@11:         } else if (value == -4) {
yading@11:             type  = "t";
yading@11:             value = ffio_read_varlen(bc);
yading@11:         } else if (value < -4) {
yading@11:             type = "r";
yading@11:             get_s(bc);
yading@11:         } else {
yading@11:             type = "v";
yading@11:         }
yading@11: 
yading@11:         if (stream_id_plus1 > s->nb_streams) {
yading@11:             av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
yading@11:             continue;
yading@11:         }
yading@11: 
yading@11:         if (!strcmp(type, "UTF-8")) {
yading@11:             if (chapter_id == 0 && !strcmp(name, "Disposition")) {
yading@11:                 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
yading@11:                 continue;
yading@11:             }
yading@11: 
yading@11:             if (stream_id_plus1 && !strcmp(name, "r_frame_rate")) {
yading@11:                 sscanf(str_value, "%d/%d", &st->r_frame_rate.num, &st->r_frame_rate.den);
yading@11:                 if (st->r_frame_rate.num >= 1000LL*st->r_frame_rate.den)
yading@11:                     st->r_frame_rate.num = st->r_frame_rate.den = 0;
yading@11:                 continue;
yading@11:             }
yading@11: 
yading@11:             if (metadata && av_strcasecmp(name, "Uses") &&
yading@11:                 av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces"))
yading@11:                 av_dict_set(metadata, name, str_value, 0);
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
yading@11:         av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
yading@11:         return -1;
yading@11:     }
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     AVIOContext *bc    = s->pb;
yading@11:     int64_t end;
yading@11:     uint64_t tmp;
yading@11: 
yading@11:     nut->last_syncpoint_pos = avio_tell(bc) - 8;
yading@11: 
yading@11:     end  = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
yading@11:     end += avio_tell(bc);
yading@11: 
yading@11:     tmp       = ffio_read_varlen(bc);
yading@11:     *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
yading@11:     if (*back_ptr < 0)
yading@11:         return AVERROR_INVALIDDATA;
yading@11: 
yading@11:     ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
yading@11:                     tmp / nut->time_base_count);
yading@11: 
yading@11:     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
yading@11:         av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
yading@11:         return AVERROR_INVALIDDATA;
yading@11:     }
yading@11: 
yading@11:     *ts = tmp / nut->time_base_count *
yading@11:           av_q2d(nut->time_base[tmp % nut->time_base_count]) * AV_TIME_BASE;
yading@11:     ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: //FIXME calculate exactly, this is just a good approximation.
yading@11: static int64_t find_duration(NUTContext *nut, int64_t filesize)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     int64_t duration = 0;
yading@11: 
yading@11:     int64_t pos = FFMAX(0, filesize - 2*nut->max_distance);
yading@11:     for(;;){
yading@11:         int64_t ts = nut_read_timestamp(s, -1, &pos, INT64_MAX);
yading@11:         if(ts < 0)
yading@11:             break;
yading@11:         duration = FFMAX(duration, ts);
yading@11:         pos++;
yading@11:     }
yading@11:     if(duration > 0)
yading@11:         s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
yading@11:     return duration;
yading@11: }
yading@11: 
yading@11: static int find_and_decode_index(NUTContext *nut)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     AVIOContext *bc    = s->pb;
yading@11:     uint64_t tmp, end;
yading@11:     int i, j, syncpoint_count;
yading@11:     int64_t filesize = avio_size(bc);
yading@11:     int64_t *syncpoints;
yading@11:     int8_t *has_keyframe;
yading@11:     int ret = -1;
yading@11: 
yading@11:     if(filesize <= 0)
yading@11:         return -1;
yading@11: 
yading@11:     avio_seek(bc, filesize - 12, SEEK_SET);
yading@11:     avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
yading@11:     if (avio_rb64(bc) != INDEX_STARTCODE) {
yading@11:         av_log(s, AV_LOG_ERROR, "no index at the end\n");
yading@11: 
yading@11:         if(s->duration<=0)
yading@11:             s->duration = find_duration(nut, filesize);
yading@11:         return -1;
yading@11:     }
yading@11: 
yading@11:     end  = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
yading@11:     end += avio_tell(bc);
yading@11: 
yading@11:     ffio_read_varlen(bc); // max_pts
yading@11:     GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
yading@11:     syncpoints   = av_malloc(sizeof(int64_t) *  syncpoint_count);
yading@11:     has_keyframe = av_malloc(sizeof(int8_t)  * (syncpoint_count + 1));
yading@11:     for (i = 0; i < syncpoint_count; i++) {
yading@11:         syncpoints[i] = ffio_read_varlen(bc);
yading@11:         if (syncpoints[i] <= 0)
yading@11:             goto fail;
yading@11:         if (i)
yading@11:             syncpoints[i] += syncpoints[i - 1];
yading@11:     }
yading@11: 
yading@11:     for (i = 0; i < s->nb_streams; i++) {
yading@11:         int64_t last_pts = -1;
yading@11:         for (j = 0; j < syncpoint_count;) {
yading@11:             uint64_t x = ffio_read_varlen(bc);
yading@11:             int type   = x & 1;
yading@11:             int n      = j;
yading@11:             x >>= 1;
yading@11:             if (type) {
yading@11:                 int flag = x & 1;
yading@11:                 x >>= 1;
yading@11:                 if (n + x >= syncpoint_count + 1) {
yading@11:                     av_log(s, AV_LOG_ERROR, "index overflow A %d + %"PRIu64" >= %d\n", n, x, syncpoint_count + 1);
yading@11:                     goto fail;
yading@11:                 }
yading@11:                 while (x--)
yading@11:                     has_keyframe[n++] = flag;
yading@11:                 has_keyframe[n++] = !flag;
yading@11:             } else {
yading@11:                 while (x != 1) {
yading@11:                     if (n >= syncpoint_count + 1) {
yading@11:                         av_log(s, AV_LOG_ERROR, "index overflow B\n");
yading@11:                         goto fail;
yading@11:                     }
yading@11:                     has_keyframe[n++] = x & 1;
yading@11:                     x >>= 1;
yading@11:                 }
yading@11:             }
yading@11:             if (has_keyframe[0]) {
yading@11:                 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
yading@11:                 goto fail;
yading@11:             }
yading@11:             av_assert0(n <= syncpoint_count + 1);
yading@11:             for (; j < n && j < syncpoint_count; j++) {
yading@11:                 if (has_keyframe[j]) {
yading@11:                     uint64_t B, A = ffio_read_varlen(bc);
yading@11:                     if (!A) {
yading@11:                         A = ffio_read_varlen(bc);
yading@11:                         B = ffio_read_varlen(bc);
yading@11:                         // eor_pts[j][i] = last_pts + A + B
yading@11:                     } else
yading@11:                         B = 0;
yading@11:                     av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
yading@11:                                        last_pts + A, 0, 0, AVINDEX_KEYFRAME);
yading@11:                     last_pts += A + B;
yading@11:                 }
yading@11:             }
yading@11:         }
yading@11:     }
yading@11: 
yading@11:     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
yading@11:         av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
yading@11:         goto fail;
yading@11:     }
yading@11:     ret = 0;
yading@11: 
yading@11: fail:
yading@11:     av_free(syncpoints);
yading@11:     av_free(has_keyframe);
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: static int nut_read_header(AVFormatContext *s)
yading@11: {
yading@11:     NUTContext *nut = s->priv_data;
yading@11:     AVIOContext *bc = s->pb;
yading@11:     int64_t pos;
yading@11:     int initialized_stream_count;
yading@11: 
yading@11:     nut->avf = s;
yading@11: 
yading@11:     /* main header */
yading@11:     pos = 0;
yading@11:     do {
yading@11:         pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
yading@11:         if (pos < 0 + 1) {
yading@11:             av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         }
yading@11:     } while (decode_main_header(nut) < 0);
yading@11: 
yading@11:     /* stream headers */
yading@11:     pos = 0;
yading@11:     for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
yading@11:         pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
yading@11:         if (pos < 0 + 1) {
yading@11:             av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         }
yading@11:         if (decode_stream_header(nut) >= 0)
yading@11:             initialized_stream_count++;
yading@11:     }
yading@11: 
yading@11:     /* info headers */
yading@11:     pos = 0;
yading@11:     for (;;) {
yading@11:         uint64_t startcode = find_any_startcode(bc, pos);
yading@11:         pos = avio_tell(bc);
yading@11: 
yading@11:         if (startcode == 0) {
yading@11:             av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
yading@11:             return AVERROR_INVALIDDATA;
yading@11:         } else if (startcode == SYNCPOINT_STARTCODE) {
yading@11:             nut->next_startcode = startcode;
yading@11:             break;
yading@11:         } else if (startcode != INFO_STARTCODE) {
yading@11:             continue;
yading@11:         }
yading@11: 
yading@11:         decode_info_header(nut);
yading@11:     }
yading@11: 
yading@11:     s->data_offset = pos - 8;
yading@11: 
yading@11:     if (bc->seekable) {
yading@11:         int64_t orig_pos = avio_tell(bc);
yading@11:         find_and_decode_index(nut);
yading@11:         avio_seek(bc, orig_pos, SEEK_SET);
yading@11:     }
yading@11:     av_assert0(nut->next_startcode == SYNCPOINT_STARTCODE);
yading@11: 
yading@11:     ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
yading@11:                                uint8_t *header_idx, int frame_code)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     AVIOContext *bc    = s->pb;
yading@11:     StreamContext *stc;
yading@11:     int size, flags, size_mul, pts_delta, i, reserved_count;
yading@11:     uint64_t tmp;
yading@11: 
yading@11:     if (avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
yading@11:         av_log(s, AV_LOG_ERROR,
yading@11:                "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
yading@11:                avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
yading@11:         return AVERROR_INVALIDDATA;
yading@11:     }
yading@11: 
yading@11:     flags          = nut->frame_code[frame_code].flags;
yading@11:     size_mul       = nut->frame_code[frame_code].size_mul;
yading@11:     size           = nut->frame_code[frame_code].size_lsb;
yading@11:     *stream_id     = nut->frame_code[frame_code].stream_id;
yading@11:     pts_delta      = nut->frame_code[frame_code].pts_delta;
yading@11:     reserved_count = nut->frame_code[frame_code].reserved_count;
yading@11:     *header_idx    = nut->frame_code[frame_code].header_idx;
yading@11: 
yading@11:     if (flags & FLAG_INVALID)
yading@11:         return AVERROR_INVALIDDATA;
yading@11:     if (flags & FLAG_CODED)
yading@11:         flags ^= ffio_read_varlen(bc);
yading@11:     if (flags & FLAG_STREAM_ID) {
yading@11:         GET_V(*stream_id, tmp < s->nb_streams);
yading@11:     }
yading@11:     stc = &nut->stream[*stream_id];
yading@11:     if (flags & FLAG_CODED_PTS) {
yading@11:         int coded_pts = ffio_read_varlen(bc);
yading@11:         // FIXME check last_pts validity?
yading@11:         if (coded_pts < (1 << stc->msb_pts_shift)) {
yading@11:             *pts = ff_lsb2full(stc, coded_pts);
yading@11:         } else
yading@11:             *pts = coded_pts - (1LL << stc->msb_pts_shift);
yading@11:     } else
yading@11:         *pts = stc->last_pts + pts_delta;
yading@11:     if (flags & FLAG_SIZE_MSB)
yading@11:         size += size_mul * ffio_read_varlen(bc);
yading@11:     if (flags & FLAG_MATCH_TIME)
yading@11:         get_s(bc);
yading@11:     if (flags & FLAG_HEADER_IDX)
yading@11:         *header_idx = ffio_read_varlen(bc);
yading@11:     if (flags & FLAG_RESERVED)
yading@11:         reserved_count = ffio_read_varlen(bc);
yading@11:     for (i = 0; i < reserved_count; i++)
yading@11:         ffio_read_varlen(bc);
yading@11: 
yading@11:     if (*header_idx >= (unsigned)nut->header_count) {
yading@11:         av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
yading@11:         return AVERROR_INVALIDDATA;
yading@11:     }
yading@11:     if (size > 4096)
yading@11:         *header_idx = 0;
yading@11:     size -= nut->header_len[*header_idx];
yading@11: 
yading@11:     if (flags & FLAG_CHECKSUM) {
yading@11:         avio_rb32(bc); // FIXME check this
yading@11:     } else if (size > 2 * nut->max_distance || FFABS(stc->last_pts - *pts) >
yading@11:                stc->max_pts_distance) {
yading@11:         av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
yading@11:         return AVERROR_INVALIDDATA;
yading@11:     }
yading@11: 
yading@11:     stc->last_pts   = *pts;
yading@11:     stc->last_flags = flags;
yading@11: 
yading@11:     return size;
yading@11: }
yading@11: 
yading@11: static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
yading@11: {
yading@11:     AVFormatContext *s = nut->avf;
yading@11:     AVIOContext *bc    = s->pb;
yading@11:     int size, stream_id, discard;
yading@11:     int64_t pts, last_IP_pts;
yading@11:     StreamContext *stc;
yading@11:     uint8_t header_idx;
yading@11: 
yading@11:     size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
yading@11:     if (size < 0)
yading@11:         return size;
yading@11: 
yading@11:     stc = &nut->stream[stream_id];
yading@11: 
yading@11:     if (stc->last_flags & FLAG_KEY)
yading@11:         stc->skip_until_key_frame = 0;
yading@11: 
yading@11:     discard     = s->streams[stream_id]->discard;
yading@11:     last_IP_pts = s->streams[stream_id]->last_IP_pts;
yading@11:     if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
yading@11:         (discard >= AVDISCARD_BIDIR  && last_IP_pts != AV_NOPTS_VALUE &&
yading@11:          last_IP_pts > pts) ||
yading@11:         discard >= AVDISCARD_ALL ||
yading@11:         stc->skip_until_key_frame) {
yading@11:         avio_skip(bc, size);
yading@11:         return 1;
yading@11:     }
yading@11: 
yading@11:     if (av_new_packet(pkt, size + nut->header_len[header_idx]) < 0)
yading@11:         return AVERROR(ENOMEM);
yading@11:     memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
yading@11:     pkt->pos = avio_tell(bc); // FIXME
yading@11:     avio_read(bc, pkt->data + nut->header_len[header_idx], size);
yading@11: 
yading@11:     pkt->stream_index = stream_id;
yading@11:     if (stc->last_flags & FLAG_KEY)
yading@11:         pkt->flags |= AV_PKT_FLAG_KEY;
yading@11:     pkt->pts = pts;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
yading@11: {
yading@11:     NUTContext *nut = s->priv_data;
yading@11:     AVIOContext *bc = s->pb;
yading@11:     int i, frame_code = 0, ret, skip;
yading@11:     int64_t ts, back_ptr;
yading@11: 
yading@11:     for (;;) {
yading@11:         int64_t pos  = avio_tell(bc);
yading@11:         uint64_t tmp = nut->next_startcode;
yading@11:         nut->next_startcode = 0;
yading@11: 
yading@11:         if (tmp) {
yading@11:             pos -= 8;
yading@11:         } else {
yading@11:             frame_code = avio_r8(bc);
yading@11:             if (url_feof(bc))
yading@11:                 return -1;
yading@11:             if (frame_code == 'N') {
yading@11:                 tmp = frame_code;
yading@11:                 for (i = 1; i < 8; i++)
yading@11:                     tmp = (tmp << 8) + avio_r8(bc);
yading@11:             }
yading@11:         }
yading@11:         switch (tmp) {
yading@11:         case MAIN_STARTCODE:
yading@11:         case STREAM_STARTCODE:
yading@11:         case INDEX_STARTCODE:
yading@11:             skip = get_packetheader(nut, bc, 0, tmp);
yading@11:             avio_skip(bc, skip);
yading@11:             break;
yading@11:         case INFO_STARTCODE:
yading@11:             if (decode_info_header(nut) < 0)
yading@11:                 goto resync;
yading@11:             break;
yading@11:         case SYNCPOINT_STARTCODE:
yading@11:             if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
yading@11:                 goto resync;
yading@11:             frame_code = avio_r8(bc);
yading@11:         case 0:
yading@11:             ret = decode_frame(nut, pkt, frame_code);
yading@11:             if (ret == 0)
yading@11:                 return 0;
yading@11:             else if (ret == 1) // OK but discard packet
yading@11:                 break;
yading@11:         default:
yading@11: resync:
yading@11:             av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
yading@11:             tmp = find_any_startcode(bc, nut->last_syncpoint_pos + 1);
yading@11:             if (tmp == 0)
yading@11:                 return AVERROR_INVALIDDATA;
yading@11:             av_log(s, AV_LOG_DEBUG, "sync\n");
yading@11:             nut->next_startcode = tmp;
yading@11:         }
yading@11:     }
yading@11: }
yading@11: 
yading@11: static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
yading@11:                                   int64_t *pos_arg, int64_t pos_limit)
yading@11: {
yading@11:     NUTContext *nut = s->priv_data;
yading@11:     AVIOContext *bc = s->pb;
yading@11:     int64_t pos, pts, back_ptr;
yading@11:     av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
yading@11:            stream_index, *pos_arg, pos_limit);
yading@11: 
yading@11:     pos = *pos_arg;
yading@11:     do {
yading@11:         pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
yading@11:         if (pos < 1) {
yading@11:             av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
yading@11:             return AV_NOPTS_VALUE;
yading@11:         }
yading@11:     } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
yading@11:     *pos_arg = pos - 1;
yading@11:     av_assert0(nut->last_syncpoint_pos == *pos_arg);
yading@11: 
yading@11:     av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
yading@11:     if (stream_index == -2)
yading@11:         return back_ptr;
yading@11:     av_assert0(stream_index == -1);
yading@11:     return pts;
yading@11: }
yading@11: 
yading@11: static int read_seek(AVFormatContext *s, int stream_index,
yading@11:                      int64_t pts, int flags)
yading@11: {
yading@11:     NUTContext *nut    = s->priv_data;
yading@11:     AVStream *st       = s->streams[stream_index];
yading@11:     Syncpoint dummy    = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
yading@11:     Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
yading@11:     Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
yading@11:     int64_t pos, pos2, ts;
yading@11:     int i;
yading@11: 
yading@11:     if (st->index_entries) {
yading@11:         int index = av_index_search_timestamp(st, pts, flags);
yading@11:         if (index < 0)
yading@11:             index = av_index_search_timestamp(st, pts, flags ^ AVSEEK_FLAG_BACKWARD);
yading@11:         if (index < 0)
yading@11:             return -1;
yading@11: 
yading@11:         pos2 = st->index_entries[index].pos;
yading@11:         ts   = st->index_entries[index].timestamp;
yading@11:     } else {
yading@11:         av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
yading@11:                      (void **) next_node);
yading@11:         av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
yading@11:                next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
yading@11:                next_node[1]->ts);
yading@11:         pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
yading@11:                             next_node[1]->pos, next_node[1]->pos,
yading@11:                             next_node[0]->ts, next_node[1]->ts,
yading@11:                             AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
yading@11: 
yading@11:         if (!(flags & AVSEEK_FLAG_BACKWARD)) {
yading@11:             dummy.pos    = pos + 16;
yading@11:             next_node[1] = &nopts_sp;
yading@11:             av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
yading@11:                          (void **) next_node);
yading@11:             pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
yading@11:                                  next_node[1]->pos, next_node[1]->pos,
yading@11:                                  next_node[0]->back_ptr, next_node[1]->back_ptr,
yading@11:                                  flags, &ts, nut_read_timestamp);
yading@11:             if (pos2 >= 0)
yading@11:                 pos = pos2;
yading@11:             // FIXME dir but I think it does not matter
yading@11:         }
yading@11:         dummy.pos = pos;
yading@11:         sp = av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
yading@11:                           NULL);
yading@11: 
yading@11:         av_assert0(sp);
yading@11:         pos2 = sp->back_ptr - 15;
yading@11:     }
yading@11:     av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
yading@11:     pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
yading@11:     avio_seek(s->pb, pos, SEEK_SET);
yading@11:     av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
yading@11:     if (pos2 > pos || pos2 + 15 < pos)
yading@11:         av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
yading@11:     for (i = 0; i < s->nb_streams; i++)
yading@11:         nut->stream[i].skip_until_key_frame = 1;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int nut_read_close(AVFormatContext *s)
yading@11: {
yading@11:     NUTContext *nut = s->priv_data;
yading@11:     int i;
yading@11: 
yading@11:     av_freep(&nut->time_base);
yading@11:     av_freep(&nut->stream);
yading@11:     ff_nut_free_sp(nut);
yading@11:     for (i = 1; i < nut->header_count; i++)
yading@11:         av_freep(&nut->header[i]);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: AVInputFormat ff_nut_demuxer = {
yading@11:     .name           = "nut",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("NUT"),
yading@11:     .flags          = AVFMT_SEEK_TO_PTS,
yading@11:     .priv_data_size = sizeof(NUTContext),
yading@11:     .read_probe     = nut_probe,
yading@11:     .read_header    = nut_read_header,
yading@11:     .read_packet    = nut_read_packet,
yading@11:     .read_close     = nut_read_close,
yading@11:     .read_seek      = read_seek,
yading@11:     .extensions     = "nut",
yading@11:     .codec_tag      = ff_nut_codec_tags,
yading@11: };