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ffmpeg / libavformat / nutdec.c @ 53620bba

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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
 *
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 * 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.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
22

    
23
#include "tree.h"
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#include "nut.h"
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#include "avstring.h"
26

    
27
#undef NDEBUG
28
#include <assert.h>
29

    
30
static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){
31
    unsigned int len= ff_get_v(bc);
32

    
33
    if(len && maxlen)
34
        get_buffer(bc, string, FFMIN(len, maxlen));
35
    while(len > maxlen){
36
        get_byte(bc);
37
        len--;
38
    }
39

    
40
    if(maxlen)
41
        string[FFMIN(len, maxlen-1)]= 0;
42

    
43
    if(maxlen == len)
44
        return -1;
45
    else
46
        return 0;
47
}
48

    
49
static int64_t get_s(ByteIOContext *bc){
50
    int64_t v = ff_get_v(bc) + 1;
51

    
52
    if (v&1) return -(v>>1);
53
    else     return  (v>>1);
54
}
55

    
56
static uint64_t get_fourcc(ByteIOContext *bc){
57
    unsigned int len= ff_get_v(bc);
58

    
59
    if     (len==2) return get_le16(bc);
60
    else if(len==4) return get_le32(bc);
61
    else            return -1;
62
}
63

    
64
#ifdef TRACE
65
static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){
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    uint64_t v= ff_get_v(bc);
67

    
68
    av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
69
    return v;
70
}
71

    
72
static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){
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    int64_t v= get_s(bc);
74

    
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    av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
76
    return v;
77
}
78

    
79
static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){
80
    uint64_t v= get_vb(bc);
81

    
82
    av_log(NULL, AV_LOG_DEBUG, "get_vb %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
83
    return v;
84
}
85
#define ff_get_v(bc)  get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
86
#define get_s(bc)  get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
87
#define get_vb(bc)  get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
88
#endif
89

    
90
static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum, uint64_t startcode)
91
{
92
    int64_t size;
93
//    start= url_ftell(bc) - 8;
94

    
95
    startcode= be2me_64(startcode);
96
    startcode= ff_crc04C11DB7_update(0, &startcode, 8);
97

    
98
    init_checksum(bc, ff_crc04C11DB7_update, startcode);
99
    size= ff_get_v(bc);
100
    if(size > 4096)
101
        get_be32(bc);
102
    if(get_checksum(bc) && size > 4096)
103
        return -1;
104

    
105
    init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
106

    
107
    return size;
108
}
109

    
110
static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){
111
    uint64_t state=0;
112

    
113
    if(pos >= 0)
114
        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
115

    
116
    while(!url_feof(bc)){
117
        state= (state<<8) | get_byte(bc);
118
        if((state>>56) != 'N')
119
            continue;
120
        switch(state){
121
        case MAIN_STARTCODE:
122
        case STREAM_STARTCODE:
123
        case SYNCPOINT_STARTCODE:
124
        case INFO_STARTCODE:
125
        case INDEX_STARTCODE:
126
            return state;
127
        }
128
    }
129

    
130
    return 0;
131
}
132

    
133
/**
134
 * Find the given startcode.
135
 * @param code the startcode
136
 * @param pos the start position of the search, or -1 if the current position
137
 * @returns the position of the startcode or -1 if not found
138
 */
139
static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){
140
    for(;;){
141
        uint64_t startcode= find_any_startcode(bc, pos);
142
        if(startcode == code)
143
            return url_ftell(bc) - 8;
144
        else if(startcode == 0)
145
            return -1;
146
        pos=-1;
147
    }
148
}
149

    
150
static int nut_probe(AVProbeData *p){
151
    int i;
152
    uint64_t code= 0;
153

    
154
    for (i = 0; i < p->buf_size; i++) {
155
        code = (code << 8) | p->buf[i];
156
        if (code == MAIN_STARTCODE)
157
            return AVPROBE_SCORE_MAX;
158
    }
159
    return 0;
160
}
161

    
162
#define GET_V(dst, check) \
163
    tmp= ff_get_v(bc);\
164
    if(!(check)){\
165
        av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);\
166
        return -1;\
167
    }\
168
    dst= tmp;
169

    
170
static int skip_reserved(ByteIOContext *bc, int64_t pos){
171
    pos -= url_ftell(bc);
172
    if(pos<0){
173
        url_fseek(bc, pos, SEEK_CUR);
174
        return -1;
175
    }else{
176
        while(pos--)
177
            get_byte(bc);
178
        return 0;
179
    }
180
}
181

    
182
static int decode_main_header(NUTContext *nut){
183
    AVFormatContext *s= nut->avf;
184
    ByteIOContext *bc = s->pb;
185
    uint64_t tmp, end;
186
    unsigned int stream_count;
187
    int i, j, tmp_stream, tmp_mul, tmp_pts, tmp_size, count, tmp_res, tmp_head_idx;
188
    int64_t tmp_match;
189

    
190
    end= get_packetheader(nut, bc, 1, MAIN_STARTCODE);
191
    end += url_ftell(bc);
192

    
193
    GET_V(tmp              , tmp >=2 && tmp <= 3)
194
    GET_V(stream_count     , tmp > 0 && tmp <=MAX_STREAMS)
195

    
196
    nut->max_distance = ff_get_v(bc);
197
    if(nut->max_distance > 65536){
198
        av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
199
        nut->max_distance= 65536;
200
    }
201

    
202
    GET_V(nut->time_base_count, tmp>0 && tmp<INT_MAX / sizeof(AVRational))
203
    nut->time_base= av_malloc(nut->time_base_count * sizeof(AVRational));
204

    
205
    for(i=0; i<nut->time_base_count; i++){
206
        GET_V(nut->time_base[i].num, tmp>0 && tmp<(1ULL<<31))
207
        GET_V(nut->time_base[i].den, tmp>0 && tmp<(1ULL<<31))
208
        if(ff_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1){
209
            av_log(s, AV_LOG_ERROR, "time base invalid\n");
210
            return -1;
211
        }
212
    }
213
    tmp_pts=0;
214
    tmp_mul=1;
215
    tmp_stream=0;
216
    tmp_match= 1-(1LL<<62);
217
    tmp_head_idx= 0;
218
    for(i=0; i<256;){
219
        int tmp_flags = ff_get_v(bc);
220
        int tmp_fields= ff_get_v(bc);
221
        if(tmp_fields>0) tmp_pts   = get_s(bc);
222
        if(tmp_fields>1) tmp_mul   = ff_get_v(bc);
223
        if(tmp_fields>2) tmp_stream= ff_get_v(bc);
224
        if(tmp_fields>3) tmp_size  = ff_get_v(bc);
225
        else             tmp_size  = 0;
226
        if(tmp_fields>4) tmp_res   = ff_get_v(bc);
227
        else             tmp_res   = 0;
228
        if(tmp_fields>5) count     = ff_get_v(bc);
229
        else             count     = tmp_mul - tmp_size;
230
        if(tmp_fields>6) tmp_match = get_s(bc);
231
        if(tmp_fields>7) tmp_head_idx= ff_get_v(bc);
232

    
233
        while(tmp_fields-- > 8)
234
           ff_get_v(bc);
235

    
236
        if(count == 0 || i+count > 256){
237
            av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
238
            return -1;
239
        }
240
        if(tmp_stream >= stream_count){
241
            av_log(s, AV_LOG_ERROR, "illegal stream number\n");
242
            return -1;
243
        }
244

    
245
        for(j=0; j<count; j++,i++){
246
            if (i == 'N') {
247
                nut->frame_code[i].flags= FLAG_INVALID;
248
                j--;
249
                continue;
250
            }
251
            nut->frame_code[i].flags           = tmp_flags ;
252
            nut->frame_code[i].pts_delta       = tmp_pts   ;
253
            nut->frame_code[i].stream_id       = tmp_stream;
254
            nut->frame_code[i].size_mul        = tmp_mul   ;
255
            nut->frame_code[i].size_lsb        = tmp_size+j;
256
            nut->frame_code[i].reserved_count  = tmp_res   ;
257
            nut->frame_code[i].header_idx      = tmp_head_idx;
258
        }
259
    }
260
    assert(nut->frame_code['N'].flags == FLAG_INVALID);
261

    
262
    if(end > url_ftell(bc) + 4){
263
        int rem= 1024;
264
        GET_V(nut->header_count, tmp<128U)
265
        nut->header_count++;
266
        for(i=1; i<nut->header_count; i++){
267
            GET_V(nut->header_len[i], tmp>0 && tmp<256);
268
            rem -= nut->header_len[i];
269
            if(rem < 0){
270
                av_log(s, AV_LOG_ERROR, "invalid elision header\n");
271
                return -1;
272
            }
273
            nut->header[i]= av_malloc(nut->header_len[i]);
274
            get_buffer(bc, nut->header[i], nut->header_len[i]);
275
        }
276
        assert(nut->header_len[0]==0);
277
    }
278

    
279
    if(skip_reserved(bc, end) || get_checksum(bc)){
280
        av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
281
        return -1;
282
    }
283

    
284
    nut->stream = av_mallocz(sizeof(StreamContext)*stream_count);
285
    for(i=0; i<stream_count; i++){
286
        av_new_stream(s, i);
287
    }
288

    
289
    return 0;
290
}
291

    
292
static int decode_stream_header(NUTContext *nut){
293
    AVFormatContext *s= nut->avf;
294
    ByteIOContext *bc = s->pb;
295
    StreamContext *stc;
296
    int class, stream_id;
297
    uint64_t tmp, end;
298
    AVStream *st;
299

    
300
    end= get_packetheader(nut, bc, 1, STREAM_STARTCODE);
301
    end += url_ftell(bc);
302

    
303
    GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
304
    stc= &nut->stream[stream_id];
305

    
306
    st = s->streams[stream_id];
307
    if (!st)
308
        return AVERROR(ENOMEM);
309

    
310
    class = ff_get_v(bc);
311
    tmp = get_fourcc(bc);
312
    st->codec->codec_tag= tmp;
313
    switch(class)
314
    {
315
        case 0:
316
            st->codec->codec_type = CODEC_TYPE_VIDEO;
317
            st->codec->codec_id = codec_get_id(codec_bmp_tags, tmp);
318
            break;
319
        case 1:
320
            st->codec->codec_type = CODEC_TYPE_AUDIO;
321
            st->codec->codec_id = codec_get_id(codec_wav_tags, tmp);
322
            break;
323
        case 2:
324
            st->codec->codec_type = CODEC_TYPE_SUBTITLE;
325
            st->codec->codec_id = codec_get_id(ff_nut_subtitle_tags, tmp);
326
            break;
327
        case 3:
328
            st->codec->codec_type = CODEC_TYPE_DATA;
329
            break;
330
        default:
331
            av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
332
            return -1;
333
    }
334
    if(class<3 && st->codec->codec_id == CODEC_ID_NONE)
335
        av_log(s, AV_LOG_ERROR, "Unknown codec?!\n");
336

    
337
    GET_V(stc->time_base_id    , tmp < nut->time_base_count);
338
    GET_V(stc->msb_pts_shift   , tmp < 16);
339
    stc->max_pts_distance= ff_get_v(bc);
340
    GET_V(stc->decode_delay    , tmp < 1000); //sanity limit, raise this if Moore's law is true
341
    st->codec->has_b_frames= stc->decode_delay;
342
    ff_get_v(bc); //stream flags
343

    
344
    GET_V(st->codec->extradata_size, tmp < (1<<30));
345
    if(st->codec->extradata_size){
346
        st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
347
        get_buffer(bc, st->codec->extradata, st->codec->extradata_size);
348
    }
349

    
350
    if (st->codec->codec_type == CODEC_TYPE_VIDEO){
351
        GET_V(st->codec->width , tmp > 0)
352
        GET_V(st->codec->height, tmp > 0)
353
        st->codec->sample_aspect_ratio.num= ff_get_v(bc);
354
        st->codec->sample_aspect_ratio.den= ff_get_v(bc);
355
        if((!st->codec->sample_aspect_ratio.num) != (!st->codec->sample_aspect_ratio.den)){
356
            av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->codec->sample_aspect_ratio.num, st->codec->sample_aspect_ratio.den);
357
            return -1;
358
        }
359
        ff_get_v(bc); /* csp type */
360
    }else if (st->codec->codec_type == CODEC_TYPE_AUDIO){
361
        GET_V(st->codec->sample_rate , tmp > 0)
362
        ff_get_v(bc); // samplerate_den
363
        GET_V(st->codec->channels, tmp > 0)
364
    }
365
    if(skip_reserved(bc, end) || get_checksum(bc)){
366
        av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id);
367
        return -1;
368
    }
369
    stc->time_base= &nut->time_base[stc->time_base_id];
370
    av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den);
371
    return 0;
372
}
373

    
374
static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){
375
    int flag = 0, i;
376
    for (i=0; ff_nut_dispositions[i].flag; ++i) {
377
        if (!strcmp(ff_nut_dispositions[i].str, value))
378
            flag = ff_nut_dispositions[i].flag;
379
    }
380
    if (!flag)
381
        av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
382
    for (i = 0; i < avf->nb_streams; ++i)
383
        if (stream_id == i || stream_id == -1)
384
            avf->streams[i]->disposition |= flag;
385
}
386

    
387
static int decode_info_header(NUTContext *nut){
388
    AVFormatContext *s= nut->avf;
389
    ByteIOContext *bc = s->pb;
390
    uint64_t tmp;
391
    unsigned int stream_id_plus1, chapter_start, chapter_len, count;
392
    int chapter_id, i;
393
    int64_t value, end;
394
    char name[256], str_value[1024], type_str[256];
395
    const char *type;
396

    
397
    end= get_packetheader(nut, bc, 1, INFO_STARTCODE);
398
    end += url_ftell(bc);
399

    
400
    GET_V(stream_id_plus1, tmp <= s->nb_streams)
401
    chapter_id   = get_s(bc);
402
    chapter_start= ff_get_v(bc);
403
    chapter_len  = ff_get_v(bc);
404
    count        = ff_get_v(bc);
405
    for(i=0; i<count; i++){
406
        get_str(bc, name, sizeof(name));
407
        value= get_s(bc);
408
        if(value == -1){
409
            type= "UTF-8";
410
            get_str(bc, str_value, sizeof(str_value));
411
        }else if(value == -2){
412
            get_str(bc, type_str, sizeof(type_str));
413
            type= type_str;
414
            get_str(bc, str_value, sizeof(str_value));
415
        }else if(value == -3){
416
            type= "s";
417
            value= get_s(bc);
418
        }else if(value == -4){
419
            type= "t";
420
            value= ff_get_v(bc);
421
        }else if(value < -4){
422
            type= "r";
423
            get_s(bc);
424
        }else{
425
            type= "v";
426
        }
427

    
428
        if (stream_id_plus1 < 0 || stream_id_plus1 > s->nb_streams) {
429
            av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
430
            continue;
431
        }
432

    
433
        if(chapter_id==0 && !strcmp(type, "UTF-8")){
434
            if     (!strcmp(name, "Author"))
435
                av_strlcpy(s->author   , str_value, sizeof(s->author));
436
            else if(!strcmp(name, "Title"))
437
                av_strlcpy(s->title    , str_value, sizeof(s->title));
438
            else if(!strcmp(name, "Copyright"))
439
                av_strlcpy(s->copyright, str_value, sizeof(s->copyright));
440
            else if(!strcmp(name, "Description"))
441
                av_strlcpy(s->comment  , str_value, sizeof(s->comment));
442
            else if(!strcmp(name, "Disposition"))
443
                set_disposition_bits(s, str_value, stream_id_plus1 - 1);
444
        }
445
    }
446

    
447
    if(skip_reserved(bc, end) || get_checksum(bc)){
448
        av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
449
        return -1;
450
    }
451
    return 0;
452
}
453

    
454
static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){
455
    AVFormatContext *s= nut->avf;
456
    ByteIOContext *bc = s->pb;
457
    int64_t end, tmp;
458

    
459
    nut->last_syncpoint_pos= url_ftell(bc)-8;
460

    
461
    end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
462
    end += url_ftell(bc);
463

    
464
    tmp= ff_get_v(bc);
465
    *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc);
466
    if(*back_ptr < 0)
467
        return -1;
468

    
469
    ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count);
470

    
471
    if(skip_reserved(bc, end) || get_checksum(bc)){
472
        av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
473
        return -1;
474
    }
475

    
476
    *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE;
477
    ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
478

    
479
    return 0;
480
}
481

    
482
static int find_and_decode_index(NUTContext *nut){
483
    AVFormatContext *s= nut->avf;
484
    ByteIOContext *bc = s->pb;
485
    uint64_t tmp, end;
486
    int i, j, syncpoint_count;
487
    int64_t filesize= url_fsize(bc);
488
    int64_t *syncpoints;
489
    int8_t *has_keyframe;
490

    
491
    url_fseek(bc, filesize-12, SEEK_SET);
492
    url_fseek(bc, filesize-get_be64(bc), SEEK_SET);
493
    if(get_be64(bc) != INDEX_STARTCODE){
494
        av_log(s, AV_LOG_ERROR, "no index at the end\n");
495
        return -1;
496
    }
497

    
498
    end= get_packetheader(nut, bc, 1, INDEX_STARTCODE);
499
    end += url_ftell(bc);
500

    
501
    ff_get_v(bc); //max_pts
502
    GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0)
503
    syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count);
504
    has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1));
505
    for(i=0; i<syncpoint_count; i++){
506
        GET_V(syncpoints[i], tmp>0)
507
        if(i)
508
            syncpoints[i] += syncpoints[i-1];
509
    }
510

    
511
    for(i=0; i<s->nb_streams; i++){
512
        int64_t last_pts= -1;
513
        for(j=0; j<syncpoint_count;){
514
            uint64_t x= ff_get_v(bc);
515
            int type= x&1;
516
            int n= j;
517
            x>>=1;
518
            if(type){
519
                int flag= x&1;
520
                x>>=1;
521
                if(n+x >= syncpoint_count + 1){
522
                    av_log(s, AV_LOG_ERROR, "index overflow A\n");
523
                    return -1;
524
                }
525
                while(x--)
526
                    has_keyframe[n++]= flag;
527
                has_keyframe[n++]= !flag;
528
            }else{
529
                while(x != 1){
530
                    if(n>=syncpoint_count + 1){
531
                        av_log(s, AV_LOG_ERROR, "index overflow B\n");
532
                        return -1;
533
                    }
534
                    has_keyframe[n++]= x&1;
535
                    x>>=1;
536
                }
537
            }
538
            if(has_keyframe[0]){
539
                av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
540
                return -1;
541
            }
542
            assert(n<=syncpoint_count+1);
543
            for(; j<n && j<syncpoint_count; j++){
544
                if(has_keyframe[j]){
545
                    uint64_t B, A= ff_get_v(bc);
546
                    if(!A){
547
                        A= ff_get_v(bc);
548
                        B= ff_get_v(bc);
549
                        //eor_pts[j][i] = last_pts + A + B
550
                    }else
551
                        B= 0;
552
                    av_add_index_entry(
553
                        s->streams[i],
554
                        16*syncpoints[j-1],
555
                        last_pts + A,
556
                        0,
557
                        0,
558
                        AVINDEX_KEYFRAME);
559
                    last_pts += A + B;
560
                }
561
            }
562
        }
563
    }
564

    
565
    if(skip_reserved(bc, end) || get_checksum(bc)){
566
        av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
567
        return -1;
568
    }
569
    return 0;
570
}
571

    
572
static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
573
{
574
    NUTContext *nut = s->priv_data;
575
    ByteIOContext *bc = s->pb;
576
    int64_t pos;
577
    int initialized_stream_count;
578

    
579
    nut->avf= s;
580

    
581
    /* main header */
582
    pos=0;
583
    do{
584
        pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
585
        if (pos<0+1){
586
            av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
587
            return -1;
588
        }
589
    }while(decode_main_header(nut) < 0);
590

    
591
    /* stream headers */
592
    pos=0;
593
    for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){
594
        pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
595
        if (pos<0+1){
596
            av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
597
            return -1;
598
        }
599
        if(decode_stream_header(nut) >= 0)
600
            initialized_stream_count++;
601
    }
602

    
603
    /* info headers */
604
    pos=0;
605
    for(;;){
606
        uint64_t startcode= find_any_startcode(bc, pos);
607
        pos= url_ftell(bc);
608

    
609
        if(startcode==0){
610
            av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
611
            return -1;
612
        }else if(startcode == SYNCPOINT_STARTCODE){
613
            nut->next_startcode= startcode;
614
            break;
615
        }else if(startcode != INFO_STARTCODE){
616
            continue;
617
        }
618

    
619
        decode_info_header(nut);
620
    }
621

    
622
    s->data_offset= pos-8;
623

    
624
    if(!url_is_streamed(bc)){
625
        int64_t orig_pos= url_ftell(bc);
626
        find_and_decode_index(nut);
627
        url_fseek(bc, orig_pos, SEEK_SET);
628
    }
629
    assert(nut->next_startcode == SYNCPOINT_STARTCODE);
630

    
631
    return 0;
632
}
633

    
634
static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){
635
    AVFormatContext *s= nut->avf;
636
    ByteIOContext *bc = s->pb;
637
    StreamContext *stc;
638
    int size, flags, size_mul, pts_delta, i, reserved_count;
639
    uint64_t tmp;
640

    
641
    if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){
642
        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);
643
        return -1;
644
    }
645

    
646
    flags          = nut->frame_code[frame_code].flags;
647
    size_mul       = nut->frame_code[frame_code].size_mul;
648
    size           = nut->frame_code[frame_code].size_lsb;
649
    *stream_id     = nut->frame_code[frame_code].stream_id;
650
    pts_delta      = nut->frame_code[frame_code].pts_delta;
651
    reserved_count = nut->frame_code[frame_code].reserved_count;
652
    *header_idx    = nut->frame_code[frame_code].header_idx;
653

    
654
    if(flags & FLAG_INVALID)
655
        return -1;
656
    if(flags & FLAG_CODED)
657
        flags ^= ff_get_v(bc);
658
    if(flags & FLAG_STREAM_ID){
659
        GET_V(*stream_id, tmp < s->nb_streams)
660
    }
661
    stc= &nut->stream[*stream_id];
662
    if(flags&FLAG_CODED_PTS){
663
        int coded_pts= ff_get_v(bc);
664
//FIXME check last_pts validity?
665
        if(coded_pts < (1<<stc->msb_pts_shift)){
666
            *pts=ff_lsb2full(stc, coded_pts);
667
        }else
668
            *pts=coded_pts - (1<<stc->msb_pts_shift);
669
    }else
670
        *pts= stc->last_pts + pts_delta;
671
    if(flags&FLAG_SIZE_MSB){
672
        size += size_mul*ff_get_v(bc);
673
    }
674
    if(flags&FLAG_MATCH_TIME)
675
        get_s(bc);
676
    if(flags&FLAG_HEADER_IDX)
677
        *header_idx= ff_get_v(bc);
678
    if(flags&FLAG_RESERVED)
679
        reserved_count= ff_get_v(bc);
680
    for(i=0; i<reserved_count; i++)
681
        ff_get_v(bc);
682

    
683
    if(*header_idx >= (unsigned)nut->header_count){
684
        av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
685
        return -1;
686
    }
687
    if(size > 4096)
688
        *header_idx=0;
689
    size -= nut->header_len[*header_idx];
690

    
691
    if(flags&FLAG_CHECKSUM){
692
        get_be32(bc); //FIXME check this
693
    }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){
694
        av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
695
        return -1;
696
    }
697

    
698
    stc->last_pts= *pts;
699
    stc->last_flags= flags;
700

    
701
    return size;
702
}
703

    
704
static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){
705
    AVFormatContext *s= nut->avf;
706
    ByteIOContext *bc = s->pb;
707
    int size, stream_id, discard;
708
    int64_t pts, last_IP_pts;
709
    StreamContext *stc;
710
    uint8_t header_idx;
711

    
712
    size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
713
    if(size < 0)
714
        return -1;
715

    
716
    stc= &nut->stream[stream_id];
717

    
718
    if (stc->last_flags & FLAG_KEY)
719
        stc->skip_until_key_frame=0;
720

    
721
    discard= s->streams[ stream_id ]->discard;
722
    last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
723
    if(  (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY))
724
       ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
725
       || discard >= AVDISCARD_ALL
726
       || stc->skip_until_key_frame){
727
        url_fskip(bc, size);
728
        return 1;
729
    }
730

    
731
    av_new_packet(pkt, size + nut->header_len[header_idx]);
732
    memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
733
    pkt->pos= url_ftell(bc); //FIXME
734
    get_buffer(bc, pkt->data + nut->header_len[header_idx], size);
735

    
736
    pkt->stream_index = stream_id;
737
    if (stc->last_flags & FLAG_KEY)
738
        pkt->flags |= PKT_FLAG_KEY;
739
    pkt->pts = pts;
740

    
741
    return 0;
742
}
743

    
744
static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
745
{
746
    NUTContext *nut = s->priv_data;
747
    ByteIOContext *bc = s->pb;
748
    int i, frame_code=0, ret, skip;
749
    int64_t ts, back_ptr;
750

    
751
    for(;;){
752
        int64_t pos= url_ftell(bc);
753
        uint64_t tmp= nut->next_startcode;
754
        nut->next_startcode=0;
755

    
756
        if(tmp){
757
            pos-=8;
758
        }else{
759
            frame_code = get_byte(bc);
760
            if(url_feof(bc))
761
                return -1;
762
            if(frame_code == 'N'){
763
                tmp= frame_code;
764
                for(i=1; i<8; i++)
765
                    tmp = (tmp<<8) + get_byte(bc);
766
            }
767
        }
768
        switch(tmp){
769
        case MAIN_STARTCODE:
770
        case STREAM_STARTCODE:
771
        case INDEX_STARTCODE:
772
            skip= get_packetheader(nut, bc, 0, tmp);
773
            url_fseek(bc, skip, SEEK_CUR);
774
            break;
775
        case INFO_STARTCODE:
776
            if(decode_info_header(nut)<0)
777
                goto resync;
778
            break;
779
        case SYNCPOINT_STARTCODE:
780
            if(decode_syncpoint(nut, &ts, &back_ptr)<0)
781
                goto resync;
782
            frame_code = get_byte(bc);
783
        case 0:
784
            ret= decode_frame(nut, pkt, frame_code);
785
            if(ret==0)
786
                return 0;
787
            else if(ret==1) //ok but discard packet
788
                break;
789
        default:
790
resync:
791
av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
792
            tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1);
793
            if(tmp==0)
794
                return -1;
795
av_log(s, AV_LOG_DEBUG, "sync\n");
796
            nut->next_startcode= tmp;
797
        }
798
    }
799
}
800

    
801
static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
802
    NUTContext *nut = s->priv_data;
803
    ByteIOContext *bc = s->pb;
804
    int64_t pos, pts, back_ptr;
805
av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
806

    
807
    pos= *pos_arg;
808
    do{
809
        pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1;
810
        if(pos < 1){
811
            assert(nut->next_startcode == 0);
812
            av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
813
            return AV_NOPTS_VALUE;
814
        }
815
    }while(decode_syncpoint(nut, &pts, &back_ptr) < 0);
816
    *pos_arg = pos-1;
817
    assert(nut->last_syncpoint_pos == *pos_arg);
818

    
819
    av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr );
820
    if     (stream_index == -1) return pts;
821
    else if(stream_index == -2) return back_ptr;
822

    
823
assert(0);
824
}
825

    
826
static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){
827
    NUTContext *nut = s->priv_data;
828
    AVStream *st= s->streams[stream_index];
829
    syncpoint_t dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE};
830
    syncpoint_t nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE};
831
    syncpoint_t *sp, *next_node[2]= {&nopts_sp, &nopts_sp};
832
    int64_t pos, pos2, ts;
833
    int i;
834

    
835
    if(st->index_entries){
836
        int index= av_index_search_timestamp(st, pts, flags);
837
        if(index<0)
838
            return -1;
839

    
840
        pos2= st->index_entries[index].pos;
841
        ts  = st->index_entries[index].timestamp;
842
    }else{
843
        av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pts_cmp, next_node);
844
        av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos,
845
                                                    next_node[0]->ts , next_node[1]->ts);
846
        pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos,
847
                                            next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
848

    
849
        if(!(flags & AVSEEK_FLAG_BACKWARD)){
850
            dummy.pos= pos+16;
851
            next_node[1]= &nopts_sp;
852
            av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp, next_node);
853
            pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos     , next_node[1]->pos, next_node[1]->pos,
854
                                                next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp);
855
            if(pos2>=0)
856
                pos= pos2;
857
            //FIXME dir but I think it does not matter
858
        }
859
        dummy.pos= pos;
860
        sp= av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp, NULL);
861

    
862
        assert(sp);
863
        pos2= sp->back_ptr  - 15;
864
    }
865
    av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
866
    pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
867
    url_fseek(s->pb, pos, SEEK_SET);
868
    av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
869
    if(pos2 > pos || pos2 + 15 < pos){
870
        av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
871
    }
872
    for(i=0; i<s->nb_streams; i++)
873
        nut->stream[i].skip_until_key_frame=1;
874

    
875
    return 0;
876
}
877

    
878
static int nut_read_close(AVFormatContext *s)
879
{
880
    NUTContext *nut = s->priv_data;
881

    
882
    av_freep(&nut->time_base);
883
    av_freep(&nut->stream);
884

    
885
    return 0;
886
}
887

    
888
#ifdef CONFIG_NUT_DEMUXER
889
AVInputFormat nut_demuxer = {
890
    "nut",
891
    "nut format",
892
    sizeof(NUTContext),
893
    nut_probe,
894
    nut_read_header,
895
    nut_read_packet,
896
    nut_read_close,
897
    read_seek,
898
    .extensions = "nut",
899
};
900
#endif