xref: /third_party/ffmpeg/libavformat/nutdec.c

42 static int get_str(AVIOContext *bc, char *string, unsigned int maxlen)
44     unsigned int len = ffio_read_varlen(bc);
47         avio_read(bc, string, FFMIN(len, maxlen));
49         avio_r8(bc);
51         if (bc->eof_reached)
58     if (bc->eof_reached)
66 static int64_t get_s(AVIOContext *bc)
68     int64_t v = ffio_read_varlen(bc) + 1;
76 static uint64_t get_fourcc(AVIOContext *bc)
78     unsigned int len = ffio_read_varlen(bc);
81         return avio_rl16(bc);
83         return avio_rl32(bc);
90 static int get_packetheader(NUTContext *nut, AVIOContext *bc,
98     ffio_init_checksum(bc, ff_crc04C11DB7_update, startcode);
99     size = ffio_read_varlen(bc);
101         avio_rb32(bc);
102     if (ffio_get_checksum(bc) && size > 4096)
105     ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
110 static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos)
117         avio_seek(bc, pos, SEEK_SET);
118     while (!avio_feof(bc)) {
119         state = (state << 8) | avio_r8(bc);
141 static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos)
144         uint64_t startcode = find_any_startcode(bc, pos);
146             return avio_tell(bc) - 8;
168         tmp = ffio_read_varlen(bc);                                           \
177 static int skip_reserved(AVIOContext *bc, int64_t pos)
179     pos -= avio_tell(bc);
181         avio_seek(bc, pos, SEEK_CUR);
185             if (bc->eof_reached)
187             avio_r8(bc);
196     AVIOContext *bc    = s->pb;
202     length = get_packetheader(nut, bc, 1, MAIN_STARTCODE);
205     end = length + avio_tell(bc);
207     nut->version = ffio_read_varlen(bc);
215         nut->minor_version = ffio_read_varlen(bc);
219     nut->max_distance = ffio_read_varlen(bc);
246         int tmp_flags  = ffio_read_varlen(bc);
247         int tmp_fields = ffio_read_varlen(bc);
255             tmp_pts = get_s(bc);
257             tmp_mul = ffio_read_varlen(bc);
259             tmp_stream = ffio_read_varlen(bc);
261             tmp_size = ffio_read_varlen(bc);
265             tmp_res = ffio_read_varlen(bc);
269             count = ffio_read_varlen(bc);
273             get_s(bc);
275             tmp_head_idx = ffio_read_varlen(bc);
278             if (bc->eof_reached) {
283             ffio_read_varlen(bc);
320     if (end > avio_tell(bc) + 4) {
340             avio_read(bc, hdr, nut->header_len[i]);
347     if (nut->version > 3 && end > avio_tell(bc) + 4) {
348         nut->flags = ffio_read_varlen(bc);
351     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
382     AVIOContext *bc    = s->pb;
388     end  = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
389     end += avio_tell(bc);
397     class                = ffio_read_varlen(bc);
398     tmp                  = get_fourcc(bc);
440     stc->max_pts_distance = ffio_read_varlen(bc);
443     ffio_read_varlen(bc); // stream flags
447         ret = ff_get_extradata(s, st->codecpar, bc,
456         st->sample_aspect_ratio.num = ffio_read_varlen(bc);
457         st->sample_aspect_ratio.den = ffio_read_varlen(bc);
464         ffio_read_varlen(bc); /* csp type */
467         ffio_read_varlen(bc); // samplerate_den
470     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
506     AVIOContext *bc    = s->pb;
519     end  = get_packetheader(nut, bc, 1, INFO_STARTCODE);
520     end += avio_tell(bc);
523     chapter_id    = get_s(bc);
524     chapter_start = ffio_read_varlen(bc);
525     chapter_len   = ffio_read_varlen(bc);
526     count         = ffio_read_varlen(bc);
551         ret = get_str(bc, name, sizeof(name));
556         value = get_s(bc);
561             ret = get_str(bc, str_value, sizeof(str_value));
563             ret = get_str(bc, type_str, sizeof(type_str));
569             ret = get_str(bc, str_value, sizeof(str_value));
572             value = get_s(bc);
575             value = ffio_read_varlen(bc);
578             get_s(bc);
618     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
629     AVIOContext *bc    = s->pb;
634     nut->last_syncpoint_pos = avio_tell(bc) - 8;
636     end  = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
637     end += avio_tell(bc);
639     tmp       = ffio_read_varlen(bc);
640     *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
648         tmp = ffio_read_varlen(bc);
655     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
685     AVIOContext *bc    = s->pb;
688     int64_t filesize = avio_size(bc);
697     avio_seek(bc, filesize - 12, SEEK_SET);
698     avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
699     if (avio_rb64(bc) != INDEX_STARTCODE) {
707     end  = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
708     end += avio_tell(bc);
710     max_pts = ffio_read_varlen(bc);
724         syncpoints[i] = ffio_read_varlen(bc);
734             uint64_t x = ffio_read_varlen(bc);
769                     uint64_t B, A = ffio_read_varlen(bc);
771                         A = ffio_read_varlen(bc);
772                         B = ffio_read_varlen(bc);
784     if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
813     AVIOContext *bc = s->pb;
826         pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
836         pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
848         uint64_t startcode = find_any_startcode(bc, pos);
849         pos = avio_tell(bc);
866     if (bc->seekable & AVIO_SEEKABLE_NORMAL) {
867         int64_t orig_pos = avio_tell(bc);
869         avio_seek(bc, orig_pos, SEEK_SET);
878 static int read_sm_data(AVFormatContext *s, AVIOContext *bc, AVPacket *pkt, int is_meta, int64_t maxpos)
880     int count = ffio_read_varlen(bc);
893         if (avio_tell(bc) >= maxpos)
895         ret = get_str(bc, name, sizeof(name));
900         value = get_s(bc);
903             ret = get_str(bc, str_value, sizeof(str_value));
913             ret = get_str(bc, type_str, sizeof(type_str));
918             value_len = ffio_read_varlen(bc);
919             if (value_len < 0 || value_len >= maxpos - avio_tell(bc))
932                 channel_layout = avio_rl64(bc);
936                 avio_skip(bc, value_len);
941             avio_read(bc, dst, value_len);
943             value = get_s(bc);
945             value = ffio_read_varlen(bc);
947             get_s(bc);
999     if (avio_tell(bc) >= maxpos)
1009     AVIOContext *bc    = s->pb;
1015         avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
1018                avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
1033         flags ^= ffio_read_varlen(bc);
1039         int64_t coded_pts = ffio_read_varlen(bc);
1048         size += size_mul * ffio_read_varlen(bc);
1050         get_s(bc);
1052         *header_idx = ffio_read_varlen(bc);
1054         reserved_count = ffio_read_varlen(bc);
1056         if (bc->eof_reached) {
1060         ffio_read_varlen(bc);
1072         avio_rb32(bc); // FIXME check this
1091     AVIOContext *bc    = s->pb;
1113         avio_skip(bc, size);
1122     pkt->pos = avio_tell(bc); // FIXME
1125         if (read_sm_data(s, bc, pkt, 0, pkt->pos + size) < 0) {
1129         if (read_sm_data(s, bc, pkt, 1, pkt->pos + size) < 0) {
1133         sm_size = avio_tell(bc) - pkt->pos;
1138     ret = avio_read(bc, pkt->data + nut->header_len[header_idx], size);
1159     AVIOContext *bc = s->pb;
1164         int64_t pos  = avio_tell(bc);
1171             frame_code = avio_r8(bc);
1172             if (avio_feof(bc))
1177                     tmp = (tmp << 8) + avio_r8(bc);
1184             skip = get_packetheader(nut, bc, 0, tmp);
1185             avio_skip(bc, skip);
1194             frame_code = avio_r8(bc);
1204             tmp = find_any_startcode(bc, FFMAX(nut->last_syncpoint_pos, nut->last_resync_pos) + 1);
1205             nut->last_resync_pos = avio_tell(bc);
1218     AVIOContext *bc = s->pb;
1225         pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;

Indexes created Thu Nov 07 10:32:03 CST 2024