1 /*
2 * "NUT" Container Format demuxer
3 * Copyright (c) 2004-2006 Michael Niedermayer
4 * Copyright (c) 2003 Alex Beregszaszi
5 *
6 * This file is part of FFmpeg.
7 *
8 * FFmpeg is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
12 *
13 * FFmpeg is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
17 *
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with FFmpeg; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 */
22
23 #include "libavutil/avstring.h"
24 #include "libavutil/avassert.h"
25 #include "libavutil/bswap.h"
26 #include "libavutil/dict.h"
27 #include "libavutil/intreadwrite.h"
28 #include "libavutil/mathematics.h"
29 #include "libavutil/tree.h"
30 #include "libavcodec/bytestream.h"
31 #include "avio_internal.h"
32 #include "isom.h"
33 #include "nut.h"
34 #include "riff.h"
35
36 #define NUT_MAX_STREAMS 256 /* arbitrary sanity check value */
37
38 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
39 int64_t *pos_arg, int64_t pos_limit);
40
get_str(AVIOContext * bc,char * string,unsigned int maxlen)41 static int get_str(AVIOContext *bc, char *string, unsigned int maxlen)
42 {
43 unsigned int len = ffio_read_varlen(bc);
44
45 if (len && maxlen)
46 avio_read(bc, string, FFMIN(len, maxlen));
47 while (len > maxlen) {
48 avio_r8(bc);
49 len--;
50 if (bc->eof_reached)
51 len = maxlen;
52 }
53
54 if (maxlen)
55 string[FFMIN(len, maxlen - 1)] = 0;
56
57 if (bc->eof_reached)
58 return AVERROR_EOF;
59 if (maxlen == len)
60 return -1;
61 else
62 return 0;
63 }
64
get_s(AVIOContext * bc)65 static int64_t get_s(AVIOContext *bc)
66 {
67 int64_t v = ffio_read_varlen(bc) + 1;
68
69 if (v & 1)
70 return -(v >> 1);
71 else
72 return (v >> 1);
73 }
74
get_fourcc(AVIOContext * bc)75 static uint64_t get_fourcc(AVIOContext *bc)
76 {
77 unsigned int len = ffio_read_varlen(bc);
78
79 if (len == 2)
80 return avio_rl16(bc);
81 else if (len == 4)
82 return avio_rl32(bc);
83 else {
84 av_log(NULL, AV_LOG_ERROR, "Unsupported fourcc length %d\n", len);
85 return -1;
86 }
87 }
88
get_packetheader(NUTContext * nut,AVIOContext * bc,int calculate_checksum,uint64_t startcode)89 static int get_packetheader(NUTContext *nut, AVIOContext *bc,
90 int calculate_checksum, uint64_t startcode)
91 {
92 int64_t size;
93
94 startcode = av_be2ne64(startcode);
95 startcode = ff_crc04C11DB7_update(0, (uint8_t*) &startcode, 8);
96
97 ffio_init_checksum(bc, ff_crc04C11DB7_update, startcode);
98 size = ffio_read_varlen(bc);
99 if (size > 4096)
100 avio_rb32(bc);
101 if (ffio_get_checksum(bc) && size > 4096)
102 return -1;
103
104 ffio_init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
105
106 return size;
107 }
108
find_any_startcode(AVIOContext * bc,int64_t pos)109 static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos)
110 {
111 uint64_t state = 0;
112
113 if (pos >= 0)
114 /* Note, this may fail if the stream is not seekable, but that should
115 * not matter, as in this case we simply start where we currently are */
116 avio_seek(bc, pos, SEEK_SET);
117 while (!avio_feof(bc)) {
118 state = (state << 8) | avio_r8(bc);
119 if ((state >> 56) != 'N')
120 continue;
121 switch (state) {
122 case MAIN_STARTCODE:
123 case STREAM_STARTCODE:
124 case SYNCPOINT_STARTCODE:
125 case INFO_STARTCODE:
126 case INDEX_STARTCODE:
127 return state;
128 }
129 }
130
131 return 0;
132 }
133
134 /**
135 * Find the given startcode.
136 * @param code the startcode
137 * @param pos the start position of the search, or -1 if the current position
138 * @return the position of the startcode or -1 if not found
139 */
find_startcode(AVIOContext * bc,uint64_t code,int64_t pos)140 static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos)
141 {
142 for (;;) {
143 uint64_t startcode = find_any_startcode(bc, pos);
144 if (startcode == code)
145 return avio_tell(bc) - 8;
146 else if (startcode == 0)
147 return -1;
148 pos = -1;
149 }
150 }
151
nut_probe(const AVProbeData * p)152 static int nut_probe(const AVProbeData *p)
153 {
154 int i;
155
156 for (i = 0; i < p->buf_size-8; i++) {
157 if (AV_RB32(p->buf+i) != MAIN_STARTCODE>>32)
158 continue;
159 if (AV_RB32(p->buf+i+4) == (MAIN_STARTCODE & 0xFFFFFFFF))
160 return AVPROBE_SCORE_MAX;
161 }
162 return 0;
163 }
164
165 #define GET_V(dst, check) \
166 do { \
167 tmp = ffio_read_varlen(bc); \
168 if (!(check)) { \
169 av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp); \
170 ret = AVERROR_INVALIDDATA; \
171 goto fail; \
172 } \
173 dst = tmp; \
174 } while (0)
175
skip_reserved(AVIOContext * bc,int64_t pos)176 static int skip_reserved(AVIOContext *bc, int64_t pos)
177 {
178 pos -= avio_tell(bc);
179 if (pos < 0) {
180 avio_seek(bc, pos, SEEK_CUR);
181 return AVERROR_INVALIDDATA;
182 } else {
183 while (pos--) {
184 if (bc->eof_reached)
185 return AVERROR_INVALIDDATA;
186 avio_r8(bc);
187 }
188 return 0;
189 }
190 }
191
decode_main_header(NUTContext * nut)192 static int decode_main_header(NUTContext *nut)
193 {
194 AVFormatContext *s = nut->avf;
195 AVIOContext *bc = s->pb;
196 uint64_t tmp, end;
197 unsigned int stream_count;
198 int i, j, count, ret;
199 int tmp_stream, tmp_mul, tmp_pts, tmp_size, tmp_res, tmp_head_idx;
200
201 end = get_packetheader(nut, bc, 1, MAIN_STARTCODE);
202 end += avio_tell(bc);
203
204 nut->version = ffio_read_varlen(bc);
205 if (nut->version < NUT_MIN_VERSION ||
206 nut->version > NUT_MAX_VERSION) {
207 av_log(s, AV_LOG_ERROR, "Version %d not supported.\n",
208 nut->version);
209 return AVERROR(ENOSYS);
210 }
211 if (nut->version > 3)
212 nut->minor_version = ffio_read_varlen(bc);
213
214 GET_V(stream_count, tmp > 0 && tmp <= NUT_MAX_STREAMS);
215
216 nut->max_distance = ffio_read_varlen(bc);
217 if (nut->max_distance > 65536) {
218 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
219 nut->max_distance = 65536;
220 }
221
222 GET_V(nut->time_base_count, tmp > 0 && tmp < INT_MAX / sizeof(AVRational));
223 nut->time_base = av_malloc_array(nut->time_base_count, sizeof(AVRational));
224 if (!nut->time_base)
225 return AVERROR(ENOMEM);
226
227 for (i = 0; i < nut->time_base_count; i++) {
228 GET_V(nut->time_base[i].num, tmp > 0 && tmp < (1ULL << 31));
229 GET_V(nut->time_base[i].den, tmp > 0 && tmp < (1ULL << 31));
230 if (av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1) {
231 av_log(s, AV_LOG_ERROR, "invalid time base %d/%d\n",
232 nut->time_base[i].num,
233 nut->time_base[i].den);
234 ret = AVERROR_INVALIDDATA;
235 goto fail;
236 }
237 }
238 tmp_pts = 0;
239 tmp_mul = 1;
240 tmp_stream = 0;
241 tmp_head_idx = 0;
242 for (i = 0; i < 256;) {
243 int tmp_flags = ffio_read_varlen(bc);
244 int tmp_fields = ffio_read_varlen(bc);
245
246 if (tmp_fields > 0)
247 tmp_pts = get_s(bc);
248 if (tmp_fields > 1)
249 tmp_mul = ffio_read_varlen(bc);
250 if (tmp_fields > 2)
251 tmp_stream = ffio_read_varlen(bc);
252 if (tmp_fields > 3)
253 tmp_size = ffio_read_varlen(bc);
254 else
255 tmp_size = 0;
256 if (tmp_fields > 4)
257 tmp_res = ffio_read_varlen(bc);
258 else
259 tmp_res = 0;
260 if (tmp_fields > 5)
261 count = ffio_read_varlen(bc);
262 else
263 count = tmp_mul - tmp_size;
264 if (tmp_fields > 6)
265 get_s(bc);
266 if (tmp_fields > 7)
267 tmp_head_idx = ffio_read_varlen(bc);
268
269 while (tmp_fields-- > 8) {
270 if (bc->eof_reached) {
271 av_log(s, AV_LOG_ERROR, "reached EOF while decoding main header\n");
272 ret = AVERROR_INVALIDDATA;
273 goto fail;
274 }
275 ffio_read_varlen(bc);
276 }
277
278 if (count <= 0 || count > 256 - (i <= 'N') - i) {
279 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
280 ret = AVERROR_INVALIDDATA;
281 goto fail;
282 }
283 if (tmp_stream >= stream_count) {
284 av_log(s, AV_LOG_ERROR, "illegal stream number %d >= %d\n",
285 tmp_stream, stream_count);
286 ret = AVERROR_INVALIDDATA;
287 goto fail;
288 }
289
290 for (j = 0; j < count; j++, i++) {
291 if (i == 'N') {
292 nut->frame_code[i].flags = FLAG_INVALID;
293 j--;
294 continue;
295 }
296 nut->frame_code[i].flags = tmp_flags;
297 nut->frame_code[i].pts_delta = tmp_pts;
298 nut->frame_code[i].stream_id = tmp_stream;
299 nut->frame_code[i].size_mul = tmp_mul;
300 nut->frame_code[i].size_lsb = tmp_size + j;
301 nut->frame_code[i].reserved_count = tmp_res;
302 nut->frame_code[i].header_idx = tmp_head_idx;
303 }
304 }
305 av_assert0(nut->frame_code['N'].flags == FLAG_INVALID);
306
307 if (end > avio_tell(bc) + 4) {
308 int rem = 1024;
309 GET_V(nut->header_count, tmp < 128U);
310 nut->header_count++;
311 for (i = 1; i < nut->header_count; i++) {
312 uint8_t *hdr;
313 GET_V(nut->header_len[i], tmp > 0 && tmp < 256);
314 if (rem < nut->header_len[i]) {
315 av_log(s, AV_LOG_ERROR,
316 "invalid elision header %d : %d > %d\n",
317 i, nut->header_len[i], rem);
318 ret = AVERROR_INVALIDDATA;
319 goto fail;
320 }
321 rem -= nut->header_len[i];
322 hdr = av_malloc(nut->header_len[i]);
323 if (!hdr) {
324 ret = AVERROR(ENOMEM);
325 goto fail;
326 }
327 avio_read(bc, hdr, nut->header_len[i]);
328 nut->header[i] = hdr;
329 }
330 av_assert0(nut->header_len[0] == 0);
331 }
332
333 // flags had been effectively introduced in version 4
334 if (nut->version > 3 && end > avio_tell(bc) + 4) {
335 nut->flags = ffio_read_varlen(bc);
336 }
337
338 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
339 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
340 ret = AVERROR_INVALIDDATA;
341 goto fail;
342 }
343
344 nut->stream = av_calloc(stream_count, sizeof(StreamContext));
345 if (!nut->stream) {
346 ret = AVERROR(ENOMEM);
347 goto fail;
348 }
349 for (i = 0; i < stream_count; i++) {
350 if (!avformat_new_stream(s, NULL)) {
351 ret = AVERROR(ENOMEM);
352 goto fail;
353 }
354 }
355
356 return 0;
357 fail:
358 av_freep(&nut->time_base);
359 for (i = 1; i < nut->header_count; i++) {
360 av_freep(&nut->header[i]);
361 }
362 nut->header_count = 0;
363 return ret;
364 }
365
decode_stream_header(NUTContext * nut)366 static int decode_stream_header(NUTContext *nut)
367 {
368 AVFormatContext *s = nut->avf;
369 AVIOContext *bc = s->pb;
370 StreamContext *stc;
371 int class, stream_id, ret;
372 uint64_t tmp, end;
373 AVStream *st = NULL;
374
375 end = get_packetheader(nut, bc, 1, STREAM_STARTCODE);
376 end += avio_tell(bc);
377
378 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
379 stc = &nut->stream[stream_id];
380 st = s->streams[stream_id];
381 if (!st)
382 return AVERROR(ENOMEM);
383
384 class = ffio_read_varlen(bc);
385 tmp = get_fourcc(bc);
386 st->codecpar->codec_tag = tmp;
387 switch (class) {
388 case 0:
389 st->codecpar->codec_type = AVMEDIA_TYPE_VIDEO;
390 st->codecpar->codec_id = av_codec_get_id((const AVCodecTag * const []) {
391 ff_nut_video_tags,
392 ff_codec_bmp_tags,
393 ff_codec_movvideo_tags,
394 0
395 },
396 tmp);
397 break;
398 case 1:
399 st->codecpar->codec_type = AVMEDIA_TYPE_AUDIO;
400 st->codecpar->codec_id = av_codec_get_id((const AVCodecTag * const []) {
401 ff_nut_audio_tags,
402 ff_codec_wav_tags,
403 ff_nut_audio_extra_tags,
404 0
405 },
406 tmp);
407 break;
408 case 2:
409 st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
410 st->codecpar->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
411 break;
412 case 3:
413 st->codecpar->codec_type = AVMEDIA_TYPE_DATA;
414 st->codecpar->codec_id = ff_codec_get_id(ff_nut_data_tags, tmp);
415 break;
416 default:
417 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
418 return AVERROR(ENOSYS);
419 }
420 if (class < 3 && st->codecpar->codec_id == AV_CODEC_ID_NONE)
421 av_log(s, AV_LOG_ERROR,
422 "Unknown codec tag '0x%04x' for stream number %d\n",
423 (unsigned int) tmp, stream_id);
424
425 GET_V(stc->time_base_id, tmp < nut->time_base_count);
426 GET_V(stc->msb_pts_shift, tmp < 16);
427 stc->max_pts_distance = ffio_read_varlen(bc);
428 GET_V(stc->decode_delay, tmp < 1000); // sanity limit, raise this if Moore's law is true
429 st->codecpar->video_delay = stc->decode_delay;
430 ffio_read_varlen(bc); // stream flags
431
432 GET_V(st->codecpar->extradata_size, tmp < (1 << 30));
433 if (st->codecpar->extradata_size) {
434 ret = ff_get_extradata(s, st->codecpar, bc,
435 st->codecpar->extradata_size);
436 if (ret < 0)
437 return ret;
438 }
439
440 if (st->codecpar->codec_type == AVMEDIA_TYPE_VIDEO) {
441 GET_V(st->codecpar->width, tmp > 0);
442 GET_V(st->codecpar->height, tmp > 0);
443 st->sample_aspect_ratio.num = ffio_read_varlen(bc);
444 st->sample_aspect_ratio.den = ffio_read_varlen(bc);
445 if ((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)) {
446 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n",
447 st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
448 ret = AVERROR_INVALIDDATA;
449 goto fail;
450 }
451 ffio_read_varlen(bc); /* csp type */
452 } else if (st->codecpar->codec_type == AVMEDIA_TYPE_AUDIO) {
453 GET_V(st->codecpar->sample_rate, tmp > 0);
454 ffio_read_varlen(bc); // samplerate_den
455 GET_V(st->codecpar->channels, tmp > 0);
456 }
457 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
458 av_log(s, AV_LOG_ERROR,
459 "stream header %d checksum mismatch\n", stream_id);
460 ret = AVERROR_INVALIDDATA;
461 goto fail;
462 }
463 stc->time_base = &nut->time_base[stc->time_base_id];
464 avpriv_set_pts_info(s->streams[stream_id], 63, stc->time_base->num,
465 stc->time_base->den);
466 return 0;
467 fail:
468 if (st && st->codecpar) {
469 av_freep(&st->codecpar->extradata);
470 st->codecpar->extradata_size = 0;
471 }
472 return ret;
473 }
474
set_disposition_bits(AVFormatContext * avf,char * value,int stream_id)475 static void set_disposition_bits(AVFormatContext *avf, char *value,
476 int stream_id)
477 {
478 int flag = 0, i;
479
480 for (i = 0; ff_nut_dispositions[i].flag; ++i)
481 if (!strcmp(ff_nut_dispositions[i].str, value))
482 flag = ff_nut_dispositions[i].flag;
483 if (!flag)
484 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
485 for (i = 0; i < avf->nb_streams; ++i)
486 if (stream_id == i || stream_id == -1)
487 avf->streams[i]->disposition |= flag;
488 }
489
decode_info_header(NUTContext * nut)490 static int decode_info_header(NUTContext *nut)
491 {
492 AVFormatContext *s = nut->avf;
493 AVIOContext *bc = s->pb;
494 uint64_t tmp, chapter_start, chapter_len;
495 unsigned int stream_id_plus1, count;
496 int chapter_id, i, ret = 0;
497 int64_t value, end;
498 char name[256], str_value[1024], type_str[256];
499 const char *type;
500 int *event_flags = NULL;
501 AVChapter *chapter = NULL;
502 AVStream *st = NULL;
503 AVDictionary **metadata = NULL;
504 int metadata_flag = 0;
505
506 end = get_packetheader(nut, bc, 1, INFO_STARTCODE);
507 end += avio_tell(bc);
508
509 GET_V(stream_id_plus1, tmp <= s->nb_streams);
510 chapter_id = get_s(bc);
511 chapter_start = ffio_read_varlen(bc);
512 chapter_len = ffio_read_varlen(bc);
513 count = ffio_read_varlen(bc);
514
515 if (chapter_id && !stream_id_plus1) {
516 int64_t start = chapter_start / nut->time_base_count;
517 chapter = avpriv_new_chapter(s, chapter_id,
518 nut->time_base[chapter_start %
519 nut->time_base_count],
520 start, start + chapter_len, NULL);
521 if (!chapter) {
522 av_log(s, AV_LOG_ERROR, "Could not create chapter.\n");
523 return AVERROR(ENOMEM);
524 }
525 metadata = &chapter->metadata;
526 } else if (stream_id_plus1) {
527 st = s->streams[stream_id_plus1 - 1];
528 metadata = &st->metadata;
529 event_flags = &st->event_flags;
530 metadata_flag = AVSTREAM_EVENT_FLAG_METADATA_UPDATED;
531 } else {
532 metadata = &s->metadata;
533 event_flags = &s->event_flags;
534 metadata_flag = AVFMT_EVENT_FLAG_METADATA_UPDATED;
535 }
536
537 for (i = 0; i < count; i++) {
538 ret = get_str(bc, name, sizeof(name));
539 if (ret < 0) {
540 av_log(s, AV_LOG_ERROR, "get_str failed while decoding info header\n");
541 return ret;
542 }
543 value = get_s(bc);
544 str_value[0] = 0;
545
546 if (value == -1) {
547 type = "UTF-8";
548 ret = get_str(bc, str_value, sizeof(str_value));
549 } else if (value == -2) {
550 ret = get_str(bc, type_str, sizeof(type_str));
551 if (ret < 0) {
552 av_log(s, AV_LOG_ERROR, "get_str failed while decoding info header\n");
553 return ret;
554 }
555 type = type_str;
556 ret = get_str(bc, str_value, sizeof(str_value));
557 } else if (value == -3) {
558 type = "s";
559 value = get_s(bc);
560 } else if (value == -4) {
561 type = "t";
562 value = ffio_read_varlen(bc);
563 } else if (value < -4) {
564 type = "r";
565 get_s(bc);
566 } else {
567 type = "v";
568 }
569
570 if (ret < 0) {
571 av_log(s, AV_LOG_ERROR, "get_str failed while decoding info header\n");
572 return ret;
573 }
574
575 if (stream_id_plus1 > s->nb_streams) {
576 av_log(s, AV_LOG_WARNING,
577 "invalid stream id %d for info packet\n",
578 stream_id_plus1);
579 continue;
580 }
581
582 if (!strcmp(type, "UTF-8")) {
583 if (chapter_id == 0 && !strcmp(name, "Disposition")) {
584 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
585 continue;
586 }
587
588 if (stream_id_plus1 && !strcmp(name, "r_frame_rate")) {
589 sscanf(str_value, "%d/%d", &st->r_frame_rate.num, &st->r_frame_rate.den);
590 if (st->r_frame_rate.num >= 1000LL*st->r_frame_rate.den ||
591 st->r_frame_rate.num < 0 || st->r_frame_rate.den < 0)
592 st->r_frame_rate.num = st->r_frame_rate.den = 0;
593 continue;
594 }
595
596 if (metadata && av_strcasecmp(name, "Uses") &&
597 av_strcasecmp(name, "Depends") && av_strcasecmp(name, "Replaces")) {
598 if (event_flags)
599 *event_flags |= metadata_flag;
600 av_dict_set(metadata, name, str_value, 0);
601 }
602 }
603 }
604
605 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
606 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
607 return AVERROR_INVALIDDATA;
608 }
609 fail:
610 return FFMIN(ret, 0);
611 }
612
decode_syncpoint(NUTContext * nut,int64_t * ts,int64_t * back_ptr)613 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr)
614 {
615 AVFormatContext *s = nut->avf;
616 AVIOContext *bc = s->pb;
617 int64_t end;
618 uint64_t tmp;
619 int ret;
620
621 nut->last_syncpoint_pos = avio_tell(bc) - 8;
622
623 end = get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
624 end += avio_tell(bc);
625
626 tmp = ffio_read_varlen(bc);
627 *back_ptr = nut->last_syncpoint_pos - 16 * ffio_read_varlen(bc);
628 if (*back_ptr < 0)
629 return AVERROR_INVALIDDATA;
630
631 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count],
632 tmp / nut->time_base_count);
633
634 if (nut->flags & NUT_BROADCAST) {
635 tmp = ffio_read_varlen(bc);
636 av_log(s, AV_LOG_VERBOSE, "Syncpoint wallclock %"PRId64"\n",
637 av_rescale_q(tmp / nut->time_base_count,
638 nut->time_base[tmp % nut->time_base_count],
639 AV_TIME_BASE_Q));
640 }
641
642 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
643 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
644 return AVERROR_INVALIDDATA;
645 }
646
647 *ts = tmp / nut->time_base_count *
648 av_q2d(nut->time_base[tmp % nut->time_base_count]) * AV_TIME_BASE;
649
650 if ((ret = ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts)) < 0)
651 return ret;
652
653 return 0;
654 }
655
656 //FIXME calculate exactly, this is just a good approximation.
find_duration(NUTContext * nut,int64_t filesize)657 static int64_t find_duration(NUTContext *nut, int64_t filesize)
658 {
659 AVFormatContext *s = nut->avf;
660 int64_t duration = 0;
661
662 ff_find_last_ts(s, -1, &duration, NULL, nut_read_timestamp);
663
664 if(duration > 0)
665 s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
666 return duration;
667 }
668
find_and_decode_index(NUTContext * nut)669 static int find_and_decode_index(NUTContext *nut)
670 {
671 AVFormatContext *s = nut->avf;
672 AVIOContext *bc = s->pb;
673 uint64_t tmp, end;
674 int i, j, syncpoint_count;
675 int64_t filesize = avio_size(bc);
676 int64_t *syncpoints = NULL;
677 uint64_t max_pts;
678 int8_t *has_keyframe = NULL;
679 int ret = AVERROR_INVALIDDATA;
680
681 if(filesize <= 0)
682 return -1;
683
684 avio_seek(bc, filesize - 12, SEEK_SET);
685 avio_seek(bc, filesize - avio_rb64(bc), SEEK_SET);
686 if (avio_rb64(bc) != INDEX_STARTCODE) {
687 av_log(s, AV_LOG_WARNING, "no index at the end\n");
688
689 if(s->duration<=0)
690 s->duration = find_duration(nut, filesize);
691 return ret;
692 }
693
694 end = get_packetheader(nut, bc, 1, INDEX_STARTCODE);
695 end += avio_tell(bc);
696
697 max_pts = ffio_read_varlen(bc);
698 s->duration = av_rescale_q(max_pts / nut->time_base_count,
699 nut->time_base[max_pts % nut->time_base_count],
700 AV_TIME_BASE_Q);
701 s->duration_estimation_method = AVFMT_DURATION_FROM_PTS;
702
703 GET_V(syncpoint_count, tmp < INT_MAX / 8 && tmp > 0);
704 syncpoints = av_malloc_array(syncpoint_count, sizeof(int64_t));
705 has_keyframe = av_malloc_array(syncpoint_count + 1, sizeof(int8_t));
706 if (!syncpoints || !has_keyframe) {
707 ret = AVERROR(ENOMEM);
708 goto fail;
709 }
710 for (i = 0; i < syncpoint_count; i++) {
711 syncpoints[i] = ffio_read_varlen(bc);
712 if (syncpoints[i] <= 0)
713 goto fail;
714 if (i)
715 syncpoints[i] += syncpoints[i - 1];
716 }
717
718 for (i = 0; i < s->nb_streams; i++) {
719 int64_t last_pts = -1;
720 for (j = 0; j < syncpoint_count;) {
721 uint64_t x = ffio_read_varlen(bc);
722 int type = x & 1;
723 int n = j;
724 x >>= 1;
725 if (type) {
726 int flag = x & 1;
727 x >>= 1;
728 if (n + x >= syncpoint_count + 1) {
729 av_log(s, AV_LOG_ERROR, "index overflow A %d + %"PRIu64" >= %d\n", n, x, syncpoint_count + 1);
730 goto fail;
731 }
732 while (x--)
733 has_keyframe[n++] = flag;
734 has_keyframe[n++] = !flag;
735 } else {
736 if (x <= 1) {
737 av_log(s, AV_LOG_ERROR, "index: x %"PRIu64" is invalid\n", x);
738 goto fail;
739 }
740 while (x != 1) {
741 if (n >= syncpoint_count + 1) {
742 av_log(s, AV_LOG_ERROR, "index overflow B\n");
743 goto fail;
744 }
745 has_keyframe[n++] = x & 1;
746 x >>= 1;
747 }
748 }
749 if (has_keyframe[0]) {
750 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
751 goto fail;
752 }
753 av_assert0(n <= syncpoint_count + 1);
754 for (; j < n && j < syncpoint_count; j++) {
755 if (has_keyframe[j]) {
756 uint64_t B, A = ffio_read_varlen(bc);
757 if (!A) {
758 A = ffio_read_varlen(bc);
759 B = ffio_read_varlen(bc);
760 // eor_pts[j][i] = last_pts + A + B
761 } else
762 B = 0;
763 av_add_index_entry(s->streams[i], 16 * syncpoints[j - 1],
764 last_pts + A, 0, 0, AVINDEX_KEYFRAME);
765 last_pts += A + B;
766 }
767 }
768 }
769 }
770
771 if (skip_reserved(bc, end) || ffio_get_checksum(bc)) {
772 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
773 goto fail;
774 }
775 ret = 0;
776
777 fail:
778 av_free(syncpoints);
779 av_free(has_keyframe);
780 return ret;
781 }
782
nut_read_close(AVFormatContext * s)783 static int nut_read_close(AVFormatContext *s)
784 {
785 NUTContext *nut = s->priv_data;
786 int i;
787
788 av_freep(&nut->time_base);
789 av_freep(&nut->stream);
790 ff_nut_free_sp(nut);
791 for (i = 1; i < nut->header_count; i++)
792 av_freep(&nut->header[i]);
793
794 return 0;
795 }
796
nut_read_header(AVFormatContext * s)797 static int nut_read_header(AVFormatContext *s)
798 {
799 NUTContext *nut = s->priv_data;
800 AVIOContext *bc = s->pb;
801 int64_t pos;
802 int initialized_stream_count, ret;
803
804 nut->avf = s;
805
806 /* main header */
807 pos = 0;
808 ret = 0;
809 do {
810 if (ret == AVERROR(ENOMEM))
811 return ret;
812
813 pos = find_startcode(bc, MAIN_STARTCODE, pos) + 1;
814 if (pos < 0 + 1) {
815 av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
816 goto fail;
817 }
818 } while ((ret = decode_main_header(nut)) < 0);
819
820 /* stream headers */
821 pos = 0;
822 for (initialized_stream_count = 0; initialized_stream_count < s->nb_streams;) {
823 pos = find_startcode(bc, STREAM_STARTCODE, pos) + 1;
824 if (pos < 0 + 1) {
825 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
826 goto fail;
827 }
828 if (decode_stream_header(nut) >= 0)
829 initialized_stream_count++;
830 }
831
832 /* info headers */
833 pos = 0;
834 for (;;) {
835 uint64_t startcode = find_any_startcode(bc, pos);
836 pos = avio_tell(bc);
837
838 if (startcode == 0) {
839 av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
840 goto fail;
841 } else if (startcode == SYNCPOINT_STARTCODE) {
842 nut->next_startcode = startcode;
843 break;
844 } else if (startcode != INFO_STARTCODE) {
845 continue;
846 }
847
848 decode_info_header(nut);
849 }
850
851 s->internal->data_offset = pos - 8;
852
853 if (bc->seekable & AVIO_SEEKABLE_NORMAL) {
854 int64_t orig_pos = avio_tell(bc);
855 find_and_decode_index(nut);
856 avio_seek(bc, orig_pos, SEEK_SET);
857 }
858 av_assert0(nut->next_startcode == SYNCPOINT_STARTCODE);
859
860 ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
861
862 return 0;
863
864 fail:
865 nut_read_close(s);
866
867 return AVERROR_INVALIDDATA;
868 }
869
read_sm_data(AVFormatContext * s,AVIOContext * bc,AVPacket * pkt,int is_meta,int64_t maxpos)870 static int read_sm_data(AVFormatContext *s, AVIOContext *bc, AVPacket *pkt, int is_meta, int64_t maxpos)
871 {
872 int count = ffio_read_varlen(bc);
873 int skip_start = 0;
874 int skip_end = 0;
875 int channels = 0;
876 int64_t channel_layout = 0;
877 int sample_rate = 0;
878 int width = 0;
879 int height = 0;
880 int i, ret;
881
882 for (i=0; i<count; i++) {
883 uint8_t name[256], str_value[256], type_str[256];
884 int value;
885 if (avio_tell(bc) >= maxpos)
886 return AVERROR_INVALIDDATA;
887 ret = get_str(bc, name, sizeof(name));
888 if (ret < 0) {
889 av_log(s, AV_LOG_ERROR, "get_str failed while reading sm data\n");
890 return ret;
891 }
892 value = get_s(bc);
893
894 if (value == -1) {
895 ret = get_str(bc, str_value, sizeof(str_value));
896 if (ret < 0) {
897 av_log(s, AV_LOG_ERROR, "get_str failed while reading sm data\n");
898 return ret;
899 }
900 av_log(s, AV_LOG_WARNING, "Unknown string %s / %s\n", name, str_value);
901 } else if (value == -2) {
902 uint8_t *dst = NULL;
903 int64_t v64, value_len;
904
905 ret = get_str(bc, type_str, sizeof(type_str));
906 if (ret < 0) {
907 av_log(s, AV_LOG_ERROR, "get_str failed while reading sm data\n");
908 return ret;
909 }
910 value_len = ffio_read_varlen(bc);
911 if (value_len < 0 || value_len >= maxpos - avio_tell(bc))
912 return AVERROR_INVALIDDATA;
913 if (!strcmp(name, "Palette")) {
914 dst = av_packet_new_side_data(pkt, AV_PKT_DATA_PALETTE, value_len);
915 } else if (!strcmp(name, "Extradata")) {
916 dst = av_packet_new_side_data(pkt, AV_PKT_DATA_NEW_EXTRADATA, value_len);
917 } else if (sscanf(name, "CodecSpecificSide%"SCNd64"", &v64) == 1) {
918 dst = av_packet_new_side_data(pkt, AV_PKT_DATA_MATROSKA_BLOCKADDITIONAL, value_len + 8);
919 if(!dst)
920 return AVERROR(ENOMEM);
921 AV_WB64(dst, v64);
922 dst += 8;
923 } else if (!strcmp(name, "ChannelLayout") && value_len == 8) {
924 channel_layout = avio_rl64(bc);
925 continue;
926 } else {
927 av_log(s, AV_LOG_WARNING, "Unknown data %s / %s\n", name, type_str);
928 avio_skip(bc, value_len);
929 continue;
930 }
931 if(!dst)
932 return AVERROR(ENOMEM);
933 avio_read(bc, dst, value_len);
934 } else if (value == -3) {
935 value = get_s(bc);
936 } else if (value == -4) {
937 value = ffio_read_varlen(bc);
938 } else if (value < -4) {
939 get_s(bc);
940 } else {
941 if (!strcmp(name, "SkipStart")) {
942 skip_start = value;
943 } else if (!strcmp(name, "SkipEnd")) {
944 skip_end = value;
945 } else if (!strcmp(name, "Channels")) {
946 channels = value;
947 } else if (!strcmp(name, "SampleRate")) {
948 sample_rate = value;
949 } else if (!strcmp(name, "Width")) {
950 width = value;
951 } else if (!strcmp(name, "Height")) {
952 height = value;
953 } else {
954 av_log(s, AV_LOG_WARNING, "Unknown integer %s\n", name);
955 }
956 }
957 }
958
959 if (channels || channel_layout || sample_rate || width || height) {
960 uint8_t *dst = av_packet_new_side_data(pkt, AV_PKT_DATA_PARAM_CHANGE, 28);
961 if (!dst)
962 return AVERROR(ENOMEM);
963 bytestream_put_le32(&dst,
964 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_COUNT*(!!channels) +
965 AV_SIDE_DATA_PARAM_CHANGE_CHANNEL_LAYOUT*(!!channel_layout) +
966 AV_SIDE_DATA_PARAM_CHANGE_SAMPLE_RATE*(!!sample_rate) +
967 AV_SIDE_DATA_PARAM_CHANGE_DIMENSIONS*(!!(width|height))
968 );
969 if (channels)
970 bytestream_put_le32(&dst, channels);
971 if (channel_layout)
972 bytestream_put_le64(&dst, channel_layout);
973 if (sample_rate)
974 bytestream_put_le32(&dst, sample_rate);
975 if (width || height){
976 bytestream_put_le32(&dst, width);
977 bytestream_put_le32(&dst, height);
978 }
979 }
980
981 if (skip_start || skip_end) {
982 uint8_t *dst = av_packet_new_side_data(pkt, AV_PKT_DATA_SKIP_SAMPLES, 10);
983 if (!dst)
984 return AVERROR(ENOMEM);
985 AV_WL32(dst, skip_start);
986 AV_WL32(dst+4, skip_end);
987 }
988
989 if (avio_tell(bc) >= maxpos)
990 return AVERROR_INVALIDDATA;
991
992 return 0;
993 }
994
decode_frame_header(NUTContext * nut,int64_t * pts,int * stream_id,uint8_t * header_idx,int frame_code)995 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id,
996 uint8_t *header_idx, int frame_code)
997 {
998 AVFormatContext *s = nut->avf;
999 AVIOContext *bc = s->pb;
1000 StreamContext *stc;
1001 int size, flags, size_mul, pts_delta, i, reserved_count, ret;
1002 uint64_t tmp;
1003
1004 if (!(nut->flags & NUT_PIPE) &&
1005 avio_tell(bc) > nut->last_syncpoint_pos + nut->max_distance) {
1006 av_log(s, AV_LOG_ERROR,
1007 "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n",
1008 avio_tell(bc), nut->last_syncpoint_pos, nut->max_distance);
1009 return AVERROR_INVALIDDATA;
1010 }
1011
1012 flags = nut->frame_code[frame_code].flags;
1013 size_mul = nut->frame_code[frame_code].size_mul;
1014 size = nut->frame_code[frame_code].size_lsb;
1015 *stream_id = nut->frame_code[frame_code].stream_id;
1016 pts_delta = nut->frame_code[frame_code].pts_delta;
1017 reserved_count = nut->frame_code[frame_code].reserved_count;
1018 *header_idx = nut->frame_code[frame_code].header_idx;
1019
1020 if (flags & FLAG_INVALID)
1021 return AVERROR_INVALIDDATA;
1022 if (flags & FLAG_CODED)
1023 flags ^= ffio_read_varlen(bc);
1024 if (flags & FLAG_STREAM_ID) {
1025 GET_V(*stream_id, tmp < s->nb_streams);
1026 }
1027 stc = &nut->stream[*stream_id];
1028 if (flags & FLAG_CODED_PTS) {
1029 int64_t coded_pts = ffio_read_varlen(bc);
1030 // FIXME check last_pts validity?
1031 if (coded_pts < (1LL << stc->msb_pts_shift)) {
1032 *pts = ff_lsb2full(stc, coded_pts);
1033 } else
1034 *pts = coded_pts - (1LL << stc->msb_pts_shift);
1035 } else
1036 *pts = stc->last_pts + pts_delta;
1037 if (flags & FLAG_SIZE_MSB)
1038 size += size_mul * ffio_read_varlen(bc);
1039 if (flags & FLAG_MATCH_TIME)
1040 get_s(bc);
1041 if (flags & FLAG_HEADER_IDX)
1042 *header_idx = ffio_read_varlen(bc);
1043 if (flags & FLAG_RESERVED)
1044 reserved_count = ffio_read_varlen(bc);
1045 for (i = 0; i < reserved_count; i++) {
1046 if (bc->eof_reached) {
1047 av_log(s, AV_LOG_ERROR, "reached EOF while decoding frame header\n");
1048 return AVERROR_INVALIDDATA;
1049 }
1050 ffio_read_varlen(bc);
1051 }
1052
1053 if (*header_idx >= (unsigned)nut->header_count) {
1054 av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
1055 return AVERROR_INVALIDDATA;
1056 }
1057 if (size > 4096)
1058 *header_idx = 0;
1059 size -= nut->header_len[*header_idx];
1060
1061 if (flags & FLAG_CHECKSUM) {
1062 avio_rb32(bc); // FIXME check this
1063 } else if (!(nut->flags & NUT_PIPE) &&
1064 size > 2 * nut->max_distance ||
1065 FFABS(stc->last_pts - *pts) > stc->max_pts_distance) {
1066 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
1067 return AVERROR_INVALIDDATA;
1068 }
1069
1070 stc->last_pts = *pts;
1071 stc->last_flags = flags;
1072
1073 return size;
1074 fail:
1075 return ret;
1076 }
1077
decode_frame(NUTContext * nut,AVPacket * pkt,int frame_code)1078 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code)
1079 {
1080 AVFormatContext *s = nut->avf;
1081 AVIOContext *bc = s->pb;
1082 int size, stream_id, discard, ret;
1083 int64_t pts, last_IP_pts;
1084 StreamContext *stc;
1085 uint8_t header_idx;
1086
1087 size = decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
1088 if (size < 0)
1089 return size;
1090
1091 stc = &nut->stream[stream_id];
1092
1093 if (stc->last_flags & FLAG_KEY)
1094 stc->skip_until_key_frame = 0;
1095
1096 discard = s->streams[stream_id]->discard;
1097 last_IP_pts = s->streams[stream_id]->last_IP_pts;
1098 if ((discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) ||
1099 (discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE &&
1100 last_IP_pts > pts) ||
1101 discard >= AVDISCARD_ALL ||
1102 stc->skip_until_key_frame) {
1103 avio_skip(bc, size);
1104 return 1;
1105 }
1106
1107 ret = av_new_packet(pkt, size + nut->header_len[header_idx]);
1108 if (ret < 0)
1109 return ret;
1110 if (nut->header[header_idx])
1111 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
1112 pkt->pos = avio_tell(bc); // FIXME
1113 if (stc->last_flags & FLAG_SM_DATA) {
1114 int sm_size;
1115 if (read_sm_data(s, bc, pkt, 0, pkt->pos + size) < 0) {
1116 ret = AVERROR_INVALIDDATA;
1117 goto fail;
1118 }
1119 if (read_sm_data(s, bc, pkt, 1, pkt->pos + size) < 0) {
1120 ret = AVERROR_INVALIDDATA;
1121 goto fail;
1122 }
1123 sm_size = avio_tell(bc) - pkt->pos;
1124 size -= sm_size;
1125 pkt->size -= sm_size;
1126 }
1127
1128 ret = avio_read(bc, pkt->data + nut->header_len[header_idx], size);
1129 if (ret != size) {
1130 if (ret < 0)
1131 goto fail;
1132 }
1133 av_shrink_packet(pkt, nut->header_len[header_idx] + ret);
1134
1135 pkt->stream_index = stream_id;
1136 if (stc->last_flags & FLAG_KEY)
1137 pkt->flags |= AV_PKT_FLAG_KEY;
1138 pkt->pts = pts;
1139
1140 return 0;
1141 fail:
1142 av_packet_unref(pkt);
1143 return ret;
1144 }
1145
nut_read_packet(AVFormatContext * s,AVPacket * pkt)1146 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
1147 {
1148 NUTContext *nut = s->priv_data;
1149 AVIOContext *bc = s->pb;
1150 int i, frame_code = 0, ret, skip;
1151 int64_t ts, back_ptr;
1152
1153 for (;;) {
1154 int64_t pos = avio_tell(bc);
1155 uint64_t tmp = nut->next_startcode;
1156 nut->next_startcode = 0;
1157
1158 if (tmp) {
1159 pos -= 8;
1160 } else {
1161 frame_code = avio_r8(bc);
1162 if (avio_feof(bc))
1163 return AVERROR_EOF;
1164 if (frame_code == 'N') {
1165 tmp = frame_code;
1166 for (i = 1; i < 8; i++)
1167 tmp = (tmp << 8) + avio_r8(bc);
1168 }
1169 }
1170 switch (tmp) {
1171 case MAIN_STARTCODE:
1172 case STREAM_STARTCODE:
1173 case INDEX_STARTCODE:
1174 skip = get_packetheader(nut, bc, 0, tmp);
1175 avio_skip(bc, skip);
1176 break;
1177 case INFO_STARTCODE:
1178 if (decode_info_header(nut) < 0)
1179 goto resync;
1180 break;
1181 case SYNCPOINT_STARTCODE:
1182 if (decode_syncpoint(nut, &ts, &back_ptr) < 0)
1183 goto resync;
1184 frame_code = avio_r8(bc);
1185 case 0:
1186 ret = decode_frame(nut, pkt, frame_code);
1187 if (ret == 0)
1188 return 0;
1189 else if (ret == 1) // OK but discard packet
1190 break;
1191 default:
1192 resync:
1193 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
1194 tmp = find_any_startcode(bc, FFMAX(nut->last_syncpoint_pos, nut->last_resync_pos) + 1);
1195 nut->last_resync_pos = avio_tell(bc);
1196 if (tmp == 0)
1197 return AVERROR_INVALIDDATA;
1198 av_log(s, AV_LOG_DEBUG, "sync\n");
1199 nut->next_startcode = tmp;
1200 }
1201 }
1202 }
1203
nut_read_timestamp(AVFormatContext * s,int stream_index,int64_t * pos_arg,int64_t pos_limit)1204 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index,
1205 int64_t *pos_arg, int64_t pos_limit)
1206 {
1207 NUTContext *nut = s->priv_data;
1208 AVIOContext *bc = s->pb;
1209 int64_t pos, pts, back_ptr;
1210 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n",
1211 stream_index, *pos_arg, pos_limit);
1212
1213 pos = *pos_arg;
1214 do {
1215 pos = find_startcode(bc, SYNCPOINT_STARTCODE, pos) + 1;
1216 if (pos < 1) {
1217 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
1218 return AV_NOPTS_VALUE;
1219 }
1220 } while (decode_syncpoint(nut, &pts, &back_ptr) < 0);
1221 *pos_arg = pos - 1;
1222 av_assert0(nut->last_syncpoint_pos == *pos_arg);
1223
1224 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts, back_ptr);
1225 if (stream_index == -2)
1226 return back_ptr;
1227 av_assert0(stream_index == -1);
1228 return pts;
1229 }
1230
read_seek(AVFormatContext * s,int stream_index,int64_t pts,int flags)1231 static int read_seek(AVFormatContext *s, int stream_index,
1232 int64_t pts, int flags)
1233 {
1234 NUTContext *nut = s->priv_data;
1235 AVStream *st = s->streams[stream_index];
1236 Syncpoint dummy = { .ts = pts * av_q2d(st->time_base) * AV_TIME_BASE };
1237 Syncpoint nopts_sp = { .ts = AV_NOPTS_VALUE, .back_ptr = AV_NOPTS_VALUE };
1238 Syncpoint *sp, *next_node[2] = { &nopts_sp, &nopts_sp };
1239 int64_t pos, pos2, ts;
1240 int i;
1241
1242 if (nut->flags & NUT_PIPE) {
1243 return AVERROR(ENOSYS);
1244 }
1245
1246 if (st->index_entries) {
1247 int index = av_index_search_timestamp(st, pts, flags);
1248 if (index < 0)
1249 index = av_index_search_timestamp(st, pts, flags ^ AVSEEK_FLAG_BACKWARD);
1250 if (index < 0)
1251 return -1;
1252
1253 pos2 = st->index_entries[index].pos;
1254 ts = st->index_entries[index].timestamp;
1255 } else {
1256 av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pts_cmp,
1257 (void **) next_node);
1258 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n",
1259 next_node[0]->pos, next_node[1]->pos, next_node[0]->ts,
1260 next_node[1]->ts);
1261 pos = ff_gen_search(s, -1, dummy.ts, next_node[0]->pos,
1262 next_node[1]->pos, next_node[1]->pos,
1263 next_node[0]->ts, next_node[1]->ts,
1264 AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
1265 if (pos < 0)
1266 return pos;
1267
1268 if (!(flags & AVSEEK_FLAG_BACKWARD)) {
1269 dummy.pos = pos + 16;
1270 next_node[1] = &nopts_sp;
1271 av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp,
1272 (void **) next_node);
1273 pos2 = ff_gen_search(s, -2, dummy.pos, next_node[0]->pos,
1274 next_node[1]->pos, next_node[1]->pos,
1275 next_node[0]->back_ptr, next_node[1]->back_ptr,
1276 flags, &ts, nut_read_timestamp);
1277 if (pos2 >= 0)
1278 pos = pos2;
1279 // FIXME dir but I think it does not matter
1280 }
1281 dummy.pos = pos;
1282 sp = av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp,
1283 NULL);
1284
1285 av_assert0(sp);
1286 pos2 = sp->back_ptr - 15;
1287 }
1288 av_log(s, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
1289 pos = find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
1290 avio_seek(s->pb, pos, SEEK_SET);
1291 nut->last_syncpoint_pos = pos;
1292 av_log(s, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
1293 if (pos2 > pos || pos2 + 15 < pos)
1294 av_log(s, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
1295 for (i = 0; i < s->nb_streams; i++)
1296 nut->stream[i].skip_until_key_frame = 1;
1297
1298 nut->last_resync_pos = 0;
1299
1300 return 0;
1301 }
1302
1303 AVInputFormat ff_nut_demuxer = {
1304 .name = "nut",
1305 .long_name = NULL_IF_CONFIG_SMALL("NUT"),
1306 .flags = AVFMT_SEEK_TO_PTS,
1307 .priv_data_size = sizeof(NUTContext),
1308 .read_probe = nut_probe,
1309 .read_header = nut_read_header,
1310 .read_packet = nut_read_packet,
1311 .read_close = nut_read_close,
1312 .read_seek = read_seek,
1313 .extensions = "nut",
1314 .codec_tag = ff_nut_codec_tags,
1315 };
1316