Fix build: Add intreadwrite.h and bswap.h #includes where necessary.
[ffmpeg.git] / libavformat / nutdec.c
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/bswap.h"
25 #include "libavutil/tree.h"
26 #include "nut.h"
27
28 #undef NDEBUG
29 #include <assert.h>
30
31 static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){
32     unsigned int len= ff_get_v(bc);
33
34     if(len && maxlen)
35         get_buffer(bc, string, FFMIN(len, maxlen));
36     while(len > maxlen){
37         get_byte(bc);
38         len--;
39     }
40
41     if(maxlen)
42         string[FFMIN(len, maxlen-1)]= 0;
43
44     if(maxlen == len)
45         return -1;
46     else
47         return 0;
48 }
49
50 static int64_t get_s(ByteIOContext *bc){
51     int64_t v = ff_get_v(bc) + 1;
52
53     if (v&1) return -(v>>1);
54     else     return  (v>>1);
55 }
56
57 static uint64_t get_fourcc(ByteIOContext *bc){
58     unsigned int len= ff_get_v(bc);
59
60     if     (len==2) return get_le16(bc);
61     else if(len==4) return get_le32(bc);
62     else            return -1;
63 }
64
65 #ifdef TRACE
66 static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){
67     uint64_t v= ff_get_v(bc);
68
69     av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
70     return v;
71 }
72
73 static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){
74     int64_t v= get_s(bc);
75
76     av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
77     return v;
78 }
79
80 static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){
81     uint64_t v= get_vb(bc);
82
83     av_log(NULL, AV_LOG_DEBUG, "get_vb %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
84     return v;
85 }
86 #define ff_get_v(bc)  get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
87 #define get_s(bc)  get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
88 #define get_vb(bc)  get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
89 #endif
90
91 static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum, uint64_t startcode)
92 {
93     int64_t size;
94 //    start= url_ftell(bc) - 8;
95
96     startcode= be2me_64(startcode);
97     startcode= ff_crc04C11DB7_update(0, &startcode, 8);
98
99     init_checksum(bc, ff_crc04C11DB7_update, startcode);
100     size= ff_get_v(bc);
101     if(size > 4096)
102         get_be32(bc);
103     if(get_checksum(bc) && size > 4096)
104         return -1;
105
106     init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
107
108     return size;
109 }
110
111 static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){
112     uint64_t state=0;
113
114     if(pos >= 0)
115         url_fseek(bc, pos, SEEK_SET); //note, this may fail if the stream is not seekable, but that should not matter, as in this case we simply start where we currently are
116
117     while(!url_feof(bc)){
118         state= (state<<8) | get_byte(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  * @returns the position of the startcode or -1 if not found
139  */
140 static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){
141     for(;;){
142         uint64_t startcode= find_any_startcode(bc, pos);
143         if(startcode == code)
144             return url_ftell(bc) - 8;
145         else if(startcode == 0)
146             return -1;
147         pos=-1;
148     }
149 }
150
151 static int nut_probe(AVProbeData *p){
152     int i;
153     uint64_t code= 0;
154
155     for (i = 0; i < p->buf_size; i++) {
156         code = (code << 8) | p->buf[i];
157         if (code == MAIN_STARTCODE)
158             return AVPROBE_SCORE_MAX;
159     }
160     return 0;
161 }
162
163 #define GET_V(dst, check) \
164     tmp= ff_get_v(bc);\
165     if(!(check)){\
166         av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);\
167         return -1;\
168     }\
169     dst= tmp;
170
171 static int skip_reserved(ByteIOContext *bc, int64_t pos){
172     pos -= url_ftell(bc);
173     if(pos<0){
174         url_fseek(bc, pos, SEEK_CUR);
175         return -1;
176     }else{
177         while(pos--)
178             get_byte(bc);
179         return 0;
180     }
181 }
182
183 static int decode_main_header(NUTContext *nut){
184     AVFormatContext *s= nut->avf;
185     ByteIOContext *bc = s->pb;
186     uint64_t tmp, end;
187     unsigned int stream_count;
188     int i, j, tmp_stream, tmp_mul, tmp_pts, tmp_size, count, tmp_res, tmp_head_idx;
189     int64_t tmp_match;
190
191     end= get_packetheader(nut, bc, 1, MAIN_STARTCODE);
192     end += url_ftell(bc);
193
194     GET_V(tmp              , tmp >=2 && tmp <= 3)
195     GET_V(stream_count     , tmp > 0 && tmp <=MAX_STREAMS)
196
197     nut->max_distance = ff_get_v(bc);
198     if(nut->max_distance > 65536){
199         av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
200         nut->max_distance= 65536;
201     }
202
203     GET_V(nut->time_base_count, tmp>0 && tmp<INT_MAX / sizeof(AVRational))
204     nut->time_base= av_malloc(nut->time_base_count * sizeof(AVRational));
205
206     for(i=0; i<nut->time_base_count; i++){
207         GET_V(nut->time_base[i].num, tmp>0 && tmp<(1ULL<<31))
208         GET_V(nut->time_base[i].den, tmp>0 && tmp<(1ULL<<31))
209         if(ff_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1){
210             av_log(s, AV_LOG_ERROR, "time base invalid\n");
211             return -1;
212         }
213     }
214     tmp_pts=0;
215     tmp_mul=1;
216     tmp_stream=0;
217     tmp_match= 1-(1LL<<62);
218     tmp_head_idx= 0;
219     for(i=0; i<256;){
220         int tmp_flags = ff_get_v(bc);
221         int tmp_fields= ff_get_v(bc);
222         if(tmp_fields>0) tmp_pts   = get_s(bc);
223         if(tmp_fields>1) tmp_mul   = ff_get_v(bc);
224         if(tmp_fields>2) tmp_stream= ff_get_v(bc);
225         if(tmp_fields>3) tmp_size  = ff_get_v(bc);
226         else             tmp_size  = 0;
227         if(tmp_fields>4) tmp_res   = ff_get_v(bc);
228         else             tmp_res   = 0;
229         if(tmp_fields>5) count     = ff_get_v(bc);
230         else             count     = tmp_mul - tmp_size;
231         if(tmp_fields>6) tmp_match = get_s(bc);
232         if(tmp_fields>7) tmp_head_idx= ff_get_v(bc);
233
234         while(tmp_fields-- > 8)
235            ff_get_v(bc);
236
237         if(count == 0 || i+count > 256){
238             av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
239             return -1;
240         }
241         if(tmp_stream >= stream_count){
242             av_log(s, AV_LOG_ERROR, "illegal stream number\n");
243             return -1;
244         }
245
246         for(j=0; j<count; j++,i++){
247             if (i == 'N') {
248                 nut->frame_code[i].flags= FLAG_INVALID;
249                 j--;
250                 continue;
251             }
252             nut->frame_code[i].flags           = tmp_flags ;
253             nut->frame_code[i].pts_delta       = tmp_pts   ;
254             nut->frame_code[i].stream_id       = tmp_stream;
255             nut->frame_code[i].size_mul        = tmp_mul   ;
256             nut->frame_code[i].size_lsb        = tmp_size+j;
257             nut->frame_code[i].reserved_count  = tmp_res   ;
258             nut->frame_code[i].header_idx      = tmp_head_idx;
259         }
260     }
261     assert(nut->frame_code['N'].flags == FLAG_INVALID);
262
263     if(end > url_ftell(bc) + 4){
264         int rem= 1024;
265         GET_V(nut->header_count, tmp<128U)
266         nut->header_count++;
267         for(i=1; i<nut->header_count; i++){
268             GET_V(nut->header_len[i], tmp>0 && tmp<256);
269             rem -= nut->header_len[i];
270             if(rem < 0){
271                 av_log(s, AV_LOG_ERROR, "invalid elision header\n");
272                 return -1;
273             }
274             nut->header[i]= av_malloc(nut->header_len[i]);
275             get_buffer(bc, nut->header[i], nut->header_len[i]);
276         }
277         assert(nut->header_len[0]==0);
278     }
279
280     if(skip_reserved(bc, end) || get_checksum(bc)){
281         av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
282         return -1;
283     }
284
285     nut->stream = av_mallocz(sizeof(StreamContext)*stream_count);
286     for(i=0; i<stream_count; i++){
287         av_new_stream(s, i);
288     }
289
290     return 0;
291 }
292
293 static int decode_stream_header(NUTContext *nut){
294     AVFormatContext *s= nut->avf;
295     ByteIOContext *bc = s->pb;
296     StreamContext *stc;
297     int class, stream_id;
298     uint64_t tmp, end;
299     AVStream *st;
300
301     end= get_packetheader(nut, bc, 1, STREAM_STARTCODE);
302     end += url_ftell(bc);
303
304     GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
305     stc= &nut->stream[stream_id];
306
307     st = s->streams[stream_id];
308     if (!st)
309         return AVERROR(ENOMEM);
310
311     class = ff_get_v(bc);
312     tmp = get_fourcc(bc);
313     st->codec->codec_tag= tmp;
314     switch(class)
315     {
316         case 0:
317             st->codec->codec_type = CODEC_TYPE_VIDEO;
318             st->codec->codec_id = codec_get_id(codec_bmp_tags, tmp);
319             break;
320         case 1:
321             st->codec->codec_type = CODEC_TYPE_AUDIO;
322             st->codec->codec_id = codec_get_id(codec_wav_tags, tmp);
323             break;
324         case 2:
325             st->codec->codec_type = CODEC_TYPE_SUBTITLE;
326             st->codec->codec_id = codec_get_id(ff_nut_subtitle_tags, tmp);
327             break;
328         case 3:
329             st->codec->codec_type = CODEC_TYPE_DATA;
330             break;
331         default:
332             av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
333             return -1;
334     }
335     if(class<3 && st->codec->codec_id == CODEC_ID_NONE)
336         av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
337
338     GET_V(stc->time_base_id    , tmp < nut->time_base_count);
339     GET_V(stc->msb_pts_shift   , tmp < 16);
340     stc->max_pts_distance= ff_get_v(bc);
341     GET_V(stc->decode_delay    , tmp < 1000); //sanity limit, raise this if Moore's law is true
342     st->codec->has_b_frames= stc->decode_delay;
343     ff_get_v(bc); //stream flags
344
345     GET_V(st->codec->extradata_size, tmp < (1<<30));
346     if(st->codec->extradata_size){
347         st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
348         get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
349     }
350
351     if (st->codec->codec_type == CODEC_TYPE_VIDEO){
352         GET_V(st->codec->width , tmp > 0)
353         GET_V(st->codec->height, tmp > 0)
354         st->sample_aspect_ratio.num= ff_get_v(bc);
355         st->sample_aspect_ratio.den= ff_get_v(bc);
356         if((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)){
357             av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
358             return -1;
359         }
360         ff_get_v(bc); /* csp type */
361     }else if (st->codec->codec_type == CODEC_TYPE_AUDIO){
362         GET_V(st->codec->sample_rate , tmp > 0)
363         ff_get_v(bc); // samplerate_den
364         GET_V(st->codec->channels, tmp > 0)
365     }
366     if(skip_reserved(bc, end) || get_checksum(bc)){
367         av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id);
368         return -1;
369     }
370     stc->time_base= &nut->time_base[stc->time_base_id];
371     av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den);
372     return 0;
373 }
374
375 static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){
376     int flag = 0, i;
377     for (i=0; ff_nut_dispositions[i].flag; ++i) {
378         if (!strcmp(ff_nut_dispositions[i].str, value))
379             flag = ff_nut_dispositions[i].flag;
380     }
381     if (!flag)
382         av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
383     for (i = 0; i < avf->nb_streams; ++i)
384         if (stream_id == i || stream_id == -1)
385             avf->streams[i]->disposition |= flag;
386 }
387
388 static int decode_info_header(NUTContext *nut){
389     AVFormatContext *s= nut->avf;
390     ByteIOContext *bc = s->pb;
391     uint64_t tmp;
392     unsigned int stream_id_plus1, chapter_start, chapter_len, count;
393     int chapter_id, i;
394     int64_t value, end;
395     char name[256], str_value[1024], type_str[256];
396     const char *type;
397     AVChapter *chapter= NULL;
398
399     end= get_packetheader(nut, bc, 1, INFO_STARTCODE);
400     end += url_ftell(bc);
401
402     GET_V(stream_id_plus1, tmp <= s->nb_streams)
403     chapter_id   = get_s(bc);
404     chapter_start= ff_get_v(bc);
405     chapter_len  = ff_get_v(bc);
406     count        = ff_get_v(bc);
407
408     if(chapter_id && !stream_id_plus1){
409         int64_t start= chapter_start / nut->time_base_count;
410         chapter= ff_new_chapter(s, chapter_id,
411                                 nut->time_base[chapter_start % nut->time_base_count],
412                                 start, start + chapter_len, NULL);
413     }
414
415     for(i=0; i<count; i++){
416         get_str(bc, name, sizeof(name));
417         value= get_s(bc);
418         if(value == -1){
419             type= "UTF-8";
420             get_str(bc, str_value, sizeof(str_value));
421         }else if(value == -2){
422             get_str(bc, type_str, sizeof(type_str));
423             type= type_str;
424             get_str(bc, str_value, sizeof(str_value));
425         }else if(value == -3){
426             type= "s";
427             value= get_s(bc);
428         }else if(value == -4){
429             type= "t";
430             value= ff_get_v(bc);
431         }else if(value < -4){
432             type= "r";
433             get_s(bc);
434         }else{
435             type= "v";
436         }
437
438         if (stream_id_plus1 > s->nb_streams) {
439             av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
440             continue;
441         }
442
443         if(chapter_id==0 && !strcmp(type, "UTF-8")){
444             if     (!strcmp(name, "Author"))
445                 av_strlcpy(s->author   , str_value, sizeof(s->author));
446             else if(!strcmp(name, "Title"))
447                 av_strlcpy(s->title    , str_value, sizeof(s->title));
448             else if(!strcmp(name, "Copyright"))
449                 av_strlcpy(s->copyright, str_value, sizeof(s->copyright));
450             else if(!strcmp(name, "Description"))
451                 av_strlcpy(s->comment  , str_value, sizeof(s->comment));
452             else if(!strcmp(name, "Disposition"))
453                 set_disposition_bits(s, str_value, stream_id_plus1 - 1);
454         }
455         if(chapter && !strcmp(type, "UTF-8")){
456             if(!strcmp(name, "Title"))
457                 chapter->title= av_strdup(str_value);
458         }
459     }
460
461     if(skip_reserved(bc, end) || get_checksum(bc)){
462         av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
463         return -1;
464     }
465     return 0;
466 }
467
468 static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){
469     AVFormatContext *s= nut->avf;
470     ByteIOContext *bc = s->pb;
471     int64_t end, tmp;
472
473     nut->last_syncpoint_pos= url_ftell(bc)-8;
474
475     end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
476     end += url_ftell(bc);
477
478     tmp= ff_get_v(bc);
479     *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc);
480     if(*back_ptr < 0)
481         return -1;
482
483     ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count);
484
485     if(skip_reserved(bc, end) || get_checksum(bc)){
486         av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
487         return -1;
488     }
489
490     *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE;
491     ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
492
493     return 0;
494 }
495
496 static int find_and_decode_index(NUTContext *nut){
497     AVFormatContext *s= nut->avf;
498     ByteIOContext *bc = s->pb;
499     uint64_t tmp, end;
500     int i, j, syncpoint_count;
501     int64_t filesize= url_fsize(bc);
502     int64_t *syncpoints;
503     int8_t *has_keyframe;
504     int ret= -1;
505
506     url_fseek(bc, filesize-12, SEEK_SET);
507     url_fseek(bc, filesize-get_be64(bc), SEEK_SET);
508     if(get_be64(bc) != INDEX_STARTCODE){
509         av_log(s, AV_LOG_ERROR, "no index at the end\n");
510         return -1;
511     }
512
513     end= get_packetheader(nut, bc, 1, INDEX_STARTCODE);
514     end += url_ftell(bc);
515
516     ff_get_v(bc); //max_pts
517     GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0)
518     syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count);
519     has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1));
520     for(i=0; i<syncpoint_count; i++){
521         syncpoints[i] = ff_get_v(bc);
522         if(syncpoints[i] <= 0)
523             goto fail;
524         if(i)
525             syncpoints[i] += syncpoints[i-1];
526     }
527
528     for(i=0; i<s->nb_streams; i++){
529         int64_t last_pts= -1;
530         for(j=0; j<syncpoint_count;){
531             uint64_t x= ff_get_v(bc);
532             int type= x&1;
533             int n= j;
534             x>>=1;
535             if(type){
536                 int flag= x&1;
537                 x>>=1;
538                 if(n+x >= syncpoint_count + 1){
539                     av_log(s, AV_LOG_ERROR, "index overflow A\n");
540                     goto fail;
541                 }
542                 while(x--)
543                     has_keyframe[n++]= flag;
544                 has_keyframe[n++]= !flag;
545             }else{
546                 while(x != 1){
547                     if(n>=syncpoint_count + 1){
548                         av_log(s, AV_LOG_ERROR, "index overflow B\n");
549                         goto fail;
550                     }
551                     has_keyframe[n++]= x&1;
552                     x>>=1;
553                 }
554             }
555             if(has_keyframe[0]){
556                 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
557                 goto fail;
558             }
559             assert(n<=syncpoint_count+1);
560             for(; j<n && j<syncpoint_count; j++){
561                 if(has_keyframe[j]){
562                     uint64_t B, A= ff_get_v(bc);
563                     if(!A){
564                         A= ff_get_v(bc);
565                         B= ff_get_v(bc);
566                         //eor_pts[j][i] = last_pts + A + B
567                     }else
568                         B= 0;
569                     av_add_index_entry(
570                         s->streams[i],
571                         16*syncpoints[j-1],
572                         last_pts + A,
573                         0,
574                         0,
575                         AVINDEX_KEYFRAME);
576                     last_pts += A + B;
577                 }
578             }
579         }
580     }
581
582     if(skip_reserved(bc, end) || get_checksum(bc)){
583         av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
584         goto fail;
585     }
586     ret= 0;
587 fail:
588     av_free(syncpoints);
589     av_free(has_keyframe);
590     return ret;
591 }
592
593 static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
594 {
595     NUTContext *nut = s->priv_data;
596     ByteIOContext *bc = s->pb;
597     int64_t pos;
598     int initialized_stream_count;
599
600     nut->avf= s;
601
602     /* main header */
603     pos=0;
604     do{
605         pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
606         if (pos<0+1){
607             av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
608             return -1;
609         }
610     }while(decode_main_header(nut) < 0);
611
612     /* stream headers */
613     pos=0;
614     for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){
615         pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
616         if (pos<0+1){
617             av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
618             return -1;
619         }
620         if(decode_stream_header(nut) >= 0)
621             initialized_stream_count++;
622     }
623
624     /* info headers */
625     pos=0;
626     for(;;){
627         uint64_t startcode= find_any_startcode(bc, pos);
628         pos= url_ftell(bc);
629
630         if(startcode==0){
631             av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
632             return -1;
633         }else if(startcode == SYNCPOINT_STARTCODE){
634             nut->next_startcode= startcode;
635             break;
636         }else if(startcode != INFO_STARTCODE){
637             continue;
638         }
639
640         decode_info_header(nut);
641     }
642
643     s->data_offset= pos-8;
644
645     if(!url_is_streamed(bc)){
646         int64_t orig_pos= url_ftell(bc);
647         find_and_decode_index(nut);
648         url_fseek(bc, orig_pos, SEEK_SET);
649     }
650     assert(nut->next_startcode == SYNCPOINT_STARTCODE);
651
652     return 0;
653 }
654
655 static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){
656     AVFormatContext *s= nut->avf;
657     ByteIOContext *bc = s->pb;
658     StreamContext *stc;
659     int size, flags, size_mul, pts_delta, i, reserved_count;
660     uint64_t tmp;
661
662     if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){
663         av_log(s, AV_LOG_ERROR, "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n", url_ftell(bc), nut->last_syncpoint_pos, nut->max_distance);
664         return -1;
665     }
666
667     flags          = nut->frame_code[frame_code].flags;
668     size_mul       = nut->frame_code[frame_code].size_mul;
669     size           = nut->frame_code[frame_code].size_lsb;
670     *stream_id     = nut->frame_code[frame_code].stream_id;
671     pts_delta      = nut->frame_code[frame_code].pts_delta;
672     reserved_count = nut->frame_code[frame_code].reserved_count;
673     *header_idx    = nut->frame_code[frame_code].header_idx;
674
675     if(flags & FLAG_INVALID)
676         return -1;
677     if(flags & FLAG_CODED)
678         flags ^= ff_get_v(bc);
679     if(flags & FLAG_STREAM_ID){
680         GET_V(*stream_id, tmp < s->nb_streams)
681     }
682     stc= &nut->stream[*stream_id];
683     if(flags&FLAG_CODED_PTS){
684         int coded_pts= ff_get_v(bc);
685 //FIXME check last_pts validity?
686         if(coded_pts < (1<<stc->msb_pts_shift)){
687             *pts=ff_lsb2full(stc, coded_pts);
688         }else
689             *pts=coded_pts - (1<<stc->msb_pts_shift);
690     }else
691         *pts= stc->last_pts + pts_delta;
692     if(flags&FLAG_SIZE_MSB){
693         size += size_mul*ff_get_v(bc);
694     }
695     if(flags&FLAG_MATCH_TIME)
696         get_s(bc);
697     if(flags&FLAG_HEADER_IDX)
698         *header_idx= ff_get_v(bc);
699     if(flags&FLAG_RESERVED)
700         reserved_count= ff_get_v(bc);
701     for(i=0; i<reserved_count; i++)
702         ff_get_v(bc);
703
704     if(*header_idx >= (unsigned)nut->header_count){
705         av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
706         return -1;
707     }
708     if(size > 4096)
709         *header_idx=0;
710     size -= nut->header_len[*header_idx];
711
712     if(flags&FLAG_CHECKSUM){
713         get_be32(bc); //FIXME check this
714     }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){
715         av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
716         return -1;
717     }
718
719     stc->last_pts= *pts;
720     stc->last_flags= flags;
721
722     return size;
723 }
724
725 static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){
726     AVFormatContext *s= nut->avf;
727     ByteIOContext *bc = s->pb;
728     int size, stream_id, discard;
729     int64_t pts, last_IP_pts;
730     StreamContext *stc;
731     uint8_t header_idx;
732
733     size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
734     if(size < 0)
735         return -1;
736
737     stc= &nut->stream[stream_id];
738
739     if (stc->last_flags & FLAG_KEY)
740         stc->skip_until_key_frame=0;
741
742     discard= s->streams[ stream_id ]->discard;
743     last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
744     if(  (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY))
745        ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
746        || discard >= AVDISCARD_ALL
747        || stc->skip_until_key_frame){
748         url_fskip(bc, size);
749         return 1;
750     }
751
752     av_new_packet(pkt, size + nut->header_len[header_idx]);
753     memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
754     pkt->pos= url_ftell(bc); //FIXME
755     get_buffer(bc, pkt->data + nut->header_len[header_idx], size);
756
757     pkt->stream_index = stream_id;
758     if (stc->last_flags & FLAG_KEY)
759         pkt->flags |= PKT_FLAG_KEY;
760     pkt->pts = pts;
761
762     return 0;
763 }
764
765 static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
766 {
767     NUTContext *nut = s->priv_data;
768     ByteIOContext *bc = s->pb;
769     int i, frame_code=0, ret, skip;
770     int64_t ts, back_ptr;
771
772     for(;;){
773         int64_t pos= url_ftell(bc);
774         uint64_t tmp= nut->next_startcode;
775         nut->next_startcode=0;
776
777         if(tmp){
778             pos-=8;
779         }else{
780             frame_code = get_byte(bc);
781             if(url_feof(bc))
782                 return -1;
783             if(frame_code == 'N'){
784                 tmp= frame_code;
785                 for(i=1; i<8; i++)
786                     tmp = (tmp<<8) + get_byte(bc);
787             }
788         }
789         switch(tmp){
790         case MAIN_STARTCODE:
791         case STREAM_STARTCODE:
792         case INDEX_STARTCODE:
793             skip= get_packetheader(nut, bc, 0, tmp);
794             url_fseek(bc, skip, SEEK_CUR);
795             break;
796         case INFO_STARTCODE:
797             if(decode_info_header(nut)<0)
798                 goto resync;
799             break;
800         case SYNCPOINT_STARTCODE:
801             if(decode_syncpoint(nut, &ts, &back_ptr)<0)
802                 goto resync;
803             frame_code = get_byte(bc);
804         case 0:
805             ret= decode_frame(nut, pkt, frame_code);
806             if(ret==0)
807                 return 0;
808             else if(ret==1) //ok but discard packet
809                 break;
810         default:
811 resync:
812 av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
813             tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1);
814             if(tmp==0)
815                 return -1;
816 av_log(s, AV_LOG_DEBUG, "sync\n");
817             nut->next_startcode= tmp;
818         }
819     }
820 }
821
822 static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
823     NUTContext *nut = s->priv_data;
824     ByteIOContext *bc = s->pb;
825     int64_t pos, pts, back_ptr;
826 av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
827
828     pos= *pos_arg;
829     do{
830         pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1;
831         if(pos < 1){
832             assert(nut->next_startcode == 0);
833             av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
834             return AV_NOPTS_VALUE;
835         }
836     }while(decode_syncpoint(nut, &pts, &back_ptr) < 0);
837     *pos_arg = pos-1;
838     assert(nut->last_syncpoint_pos == *pos_arg);
839
840     av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr );
841     if     (stream_index == -1) return pts;
842     else if(stream_index == -2) return back_ptr;
843
844 assert(0);
845 }
846
847 static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){
848     NUTContext *nut = s->priv_data;
849     AVStream *st= s->streams[stream_index];
850     Syncpoint dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE};
851     Syncpoint nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE};
852     Syncpoint *sp, *next_node[2]= {&nopts_sp, &nopts_sp};
853     int64_t pos, pos2, ts;
854     int i;
855
856     if(st->index_entries){
857         int index= av_index_search_timestamp(st, pts, flags);
858         if(index<0)
859             return -1;
860
861         pos2= st->index_entries[index].pos;
862         ts  = st->index_entries[index].timestamp;
863     }else{
864         av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pts_cmp, next_node);
865         av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos,
866                                                     next_node[0]->ts , next_node[1]->ts);
867         pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos,
868                                             next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
869
870         if(!(flags & AVSEEK_FLAG_BACKWARD)){
871             dummy.pos= pos+16;
872             next_node[1]= &nopts_sp;
873             av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp, next_node);
874             pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos     , next_node[1]->pos, next_node[1]->pos,
875                                                 next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp);
876             if(pos2>=0)
877                 pos= pos2;
878             //FIXME dir but I think it does not matter
879         }
880         dummy.pos= pos;
881         sp= av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp, NULL);
882
883         assert(sp);
884         pos2= sp->back_ptr  - 15;
885     }
886     av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
887     pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
888     url_fseek(s->pb, pos, SEEK_SET);
889     av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
890     if(pos2 > pos || pos2 + 15 < pos){
891         av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
892     }
893     for(i=0; i<s->nb_streams; i++)
894         nut->stream[i].skip_until_key_frame=1;
895
896     return 0;
897 }
898
899 static int nut_read_close(AVFormatContext *s)
900 {
901     NUTContext *nut = s->priv_data;
902
903     av_freep(&nut->time_base);
904     av_freep(&nut->stream);
905
906     return 0;
907 }
908
909 #ifdef CONFIG_NUT_DEMUXER
910 AVInputFormat nut_demuxer = {
911     "nut",
912     NULL_IF_CONFIG_SMALL("NUT format"),
913     sizeof(NUTContext),
914     nut_probe,
915     nut_read_header,
916     nut_read_packet,
917     nut_read_close,
918     read_seek,
919     .extensions = "nut",
920 };
921 #endif