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ffmpeg / libavformat / nutdec.c @ e356fc57

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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
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 * 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 <strings.h>
24
#include "libavutil/avstring.h"
25
#include "libavutil/bswap.h"
26
#include "libavutil/tree.h"
27
#include "nut.h"
28

    
29
#undef NDEBUG
30
#include <assert.h>
31

    
32
#if FF_API_MAX_STREAMS
33
#define NUT_MAX_STREAMS MAX_STREAMS
34
#else
35
#define NUT_MAX_STREAMS 256    /* arbitrary sanity check value */
36
#endif
37

    
38
static int get_str(AVIOContext *bc, char *string, unsigned int maxlen){
39
    unsigned int len= ff_get_v(bc);
40

    
41
    if(len && maxlen)
42
        avio_read(bc, string, FFMIN(len, maxlen));
43
    while(len > maxlen){
44
        avio_r8(bc);
45
        len--;
46
    }
47

    
48
    if(maxlen)
49
        string[FFMIN(len, maxlen-1)]= 0;
50

    
51
    if(maxlen == len)
52
        return -1;
53
    else
54
        return 0;
55
}
56

    
57
static int64_t get_s(AVIOContext *bc){
58
    int64_t v = ff_get_v(bc) + 1;
59

    
60
    if (v&1) return -(v>>1);
61
    else     return  (v>>1);
62
}
63

    
64
static uint64_t get_fourcc(AVIOContext *bc){
65
    unsigned int len= ff_get_v(bc);
66

    
67
    if     (len==2) return avio_rl16(bc);
68
    else if(len==4) return avio_rl32(bc);
69
    else            return -1;
70
}
71

    
72
#ifdef TRACE
73
static inline uint64_t get_v_trace(AVIOContext *bc, char *file, char *func, int line){
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    uint64_t v= ff_get_v(bc);
75

    
76
    av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
77
    return v;
78
}
79

    
80
static inline int64_t get_s_trace(AVIOContext *bc, char *file, char *func, int line){
81
    int64_t v= get_s(bc);
82

    
83
    av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
84
    return v;
85
}
86

    
87
static inline uint64_t get_vb_trace(AVIOContext *bc, char *file, char *func, int line){
88
    uint64_t v= get_vb(bc);
89

    
90
    av_log(NULL, AV_LOG_DEBUG, "get_vb %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);
91
    return v;
92
}
93
#define ff_get_v(bc)  get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
94
#define get_s(bc)  get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
95
#define get_vb(bc)  get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__)
96
#endif
97

    
98
static int get_packetheader(NUTContext *nut, AVIOContext *bc, int calculate_checksum, uint64_t startcode)
99
{
100
    int64_t size;
101
//    start= url_ftell(bc) - 8;
102

    
103
    startcode= av_be2ne64(startcode);
104
    startcode= ff_crc04C11DB7_update(0, (uint8_t*)&startcode, 8);
105

    
106
    init_checksum(bc, ff_crc04C11DB7_update, startcode);
107
    size= ff_get_v(bc);
108
    if(size > 4096)
109
        avio_rb32(bc);
110
    if(get_checksum(bc) && size > 4096)
111
        return -1;
112

    
113
    init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0);
114

    
115
    return size;
116
}
117

    
118
static uint64_t find_any_startcode(AVIOContext *bc, int64_t pos){
119
    uint64_t state=0;
120

    
121
    if(pos >= 0)
122
        avio_seek(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
123

    
124
    while(!url_feof(bc)){
125
        state= (state<<8) | avio_r8(bc);
126
        if((state>>56) != 'N')
127
            continue;
128
        switch(state){
129
        case MAIN_STARTCODE:
130
        case STREAM_STARTCODE:
131
        case SYNCPOINT_STARTCODE:
132
        case INFO_STARTCODE:
133
        case INDEX_STARTCODE:
134
            return state;
135
        }
136
    }
137

    
138
    return 0;
139
}
140

    
141
/**
142
 * Find the given startcode.
143
 * @param code the startcode
144
 * @param pos the start position of the search, or -1 if the current position
145
 * @return the position of the startcode or -1 if not found
146
 */
147
static int64_t find_startcode(AVIOContext *bc, uint64_t code, int64_t pos){
148
    for(;;){
149
        uint64_t startcode= find_any_startcode(bc, pos);
150
        if(startcode == code)
151
            return url_ftell(bc) - 8;
152
        else if(startcode == 0)
153
            return -1;
154
        pos=-1;
155
    }
156
}
157

    
158
static int nut_probe(AVProbeData *p){
159
    int i;
160
    uint64_t code= 0;
161

    
162
    for (i = 0; i < p->buf_size; i++) {
163
        code = (code << 8) | p->buf[i];
164
        if (code == MAIN_STARTCODE)
165
            return AVPROBE_SCORE_MAX;
166
    }
167
    return 0;
168
}
169

    
170
#define GET_V(dst, check) \
171
    tmp= ff_get_v(bc);\
172
    if(!(check)){\
173
        av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);\
174
        return -1;\
175
    }\
176
    dst= tmp;
177

    
178
static int skip_reserved(AVIOContext *bc, int64_t pos){
179
    pos -= url_ftell(bc);
180
    if(pos<0){
181
        avio_seek(bc, pos, SEEK_CUR);
182
        return -1;
183
    }else{
184
        while(pos--)
185
            avio_r8(bc);
186
        return 0;
187
    }
188
}
189

    
190
static int decode_main_header(NUTContext *nut){
191
    AVFormatContext *s= nut->avf;
192
    AVIOContext *bc = s->pb;
193
    uint64_t tmp, end;
194
    unsigned int stream_count;
195
    int i, j, tmp_stream, tmp_mul, tmp_pts, tmp_size, count, tmp_res, tmp_head_idx;
196
    int64_t tmp_match;
197

    
198
    end= get_packetheader(nut, bc, 1, MAIN_STARTCODE);
199
    end += url_ftell(bc);
200

    
201
    GET_V(tmp              , tmp >=2 && tmp <= 3)
202
    GET_V(stream_count     , tmp > 0 && tmp <= NUT_MAX_STREAMS)
203

    
204
    nut->max_distance = ff_get_v(bc);
205
    if(nut->max_distance > 65536){
206
        av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance);
207
        nut->max_distance= 65536;
208
    }
209

    
210
    GET_V(nut->time_base_count, tmp>0 && tmp<INT_MAX / sizeof(AVRational))
211
    nut->time_base= av_malloc(nut->time_base_count * sizeof(AVRational));
212

    
213
    for(i=0; i<nut->time_base_count; i++){
214
        GET_V(nut->time_base[i].num, tmp>0 && tmp<(1ULL<<31))
215
        GET_V(nut->time_base[i].den, tmp>0 && tmp<(1ULL<<31))
216
        if(av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1){
217
            av_log(s, AV_LOG_ERROR, "time base invalid\n");
218
            return AVERROR_INVALIDDATA;
219
        }
220
    }
221
    tmp_pts=0;
222
    tmp_mul=1;
223
    tmp_stream=0;
224
    tmp_match= 1-(1LL<<62);
225
    tmp_head_idx= 0;
226
    for(i=0; i<256;){
227
        int tmp_flags = ff_get_v(bc);
228
        int tmp_fields= ff_get_v(bc);
229
        if(tmp_fields>0) tmp_pts   = get_s(bc);
230
        if(tmp_fields>1) tmp_mul   = ff_get_v(bc);
231
        if(tmp_fields>2) tmp_stream= ff_get_v(bc);
232
        if(tmp_fields>3) tmp_size  = ff_get_v(bc);
233
        else             tmp_size  = 0;
234
        if(tmp_fields>4) tmp_res   = ff_get_v(bc);
235
        else             tmp_res   = 0;
236
        if(tmp_fields>5) count     = ff_get_v(bc);
237
        else             count     = tmp_mul - tmp_size;
238
        if(tmp_fields>6) tmp_match = get_s(bc);
239
        if(tmp_fields>7) tmp_head_idx= ff_get_v(bc);
240

    
241
        while(tmp_fields-- > 8)
242
           ff_get_v(bc);
243

    
244
        if(count == 0 || i+count > 256){
245
            av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i);
246
            return AVERROR_INVALIDDATA;
247
        }
248
        if(tmp_stream >= stream_count){
249
            av_log(s, AV_LOG_ERROR, "illegal stream number\n");
250
            return AVERROR_INVALIDDATA;
251
        }
252

    
253
        for(j=0; j<count; j++,i++){
254
            if (i == 'N') {
255
                nut->frame_code[i].flags= FLAG_INVALID;
256
                j--;
257
                continue;
258
            }
259
            nut->frame_code[i].flags           = tmp_flags ;
260
            nut->frame_code[i].pts_delta       = tmp_pts   ;
261
            nut->frame_code[i].stream_id       = tmp_stream;
262
            nut->frame_code[i].size_mul        = tmp_mul   ;
263
            nut->frame_code[i].size_lsb        = tmp_size+j;
264
            nut->frame_code[i].reserved_count  = tmp_res   ;
265
            nut->frame_code[i].header_idx      = tmp_head_idx;
266
        }
267
    }
268
    assert(nut->frame_code['N'].flags == FLAG_INVALID);
269

    
270
    if(end > url_ftell(bc) + 4){
271
        int rem= 1024;
272
        GET_V(nut->header_count, tmp<128U)
273
        nut->header_count++;
274
        for(i=1; i<nut->header_count; i++){
275
            GET_V(nut->header_len[i], tmp>0 && tmp<256);
276
            rem -= nut->header_len[i];
277
            if(rem < 0){
278
                av_log(s, AV_LOG_ERROR, "invalid elision header\n");
279
                return AVERROR_INVALIDDATA;
280
            }
281
            nut->header[i]= av_malloc(nut->header_len[i]);
282
            avio_read(bc, nut->header[i], nut->header_len[i]);
283
        }
284
        assert(nut->header_len[0]==0);
285
    }
286

    
287
    if(skip_reserved(bc, end) || get_checksum(bc)){
288
        av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n");
289
        return AVERROR_INVALIDDATA;
290
    }
291

    
292
    nut->stream = av_mallocz(sizeof(StreamContext)*stream_count);
293
    for(i=0; i<stream_count; i++){
294
        av_new_stream(s, i);
295
    }
296

    
297
    return 0;
298
}
299

    
300
static int decode_stream_header(NUTContext *nut){
301
    AVFormatContext *s= nut->avf;
302
    AVIOContext *bc = s->pb;
303
    StreamContext *stc;
304
    int class, stream_id;
305
    uint64_t tmp, end;
306
    AVStream *st;
307

    
308
    end= get_packetheader(nut, bc, 1, STREAM_STARTCODE);
309
    end += url_ftell(bc);
310

    
311
    GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base);
312
    stc= &nut->stream[stream_id];
313

    
314
    st = s->streams[stream_id];
315
    if (!st)
316
        return AVERROR(ENOMEM);
317

    
318
    class = ff_get_v(bc);
319
    tmp = get_fourcc(bc);
320
    st->codec->codec_tag= tmp;
321
    switch(class)
322
    {
323
        case 0:
324
            st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
325
            st->codec->codec_id = av_codec_get_id(
326
                (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, 0 },
327
                tmp);
328
            break;
329
        case 1:
330
            st->codec->codec_type = AVMEDIA_TYPE_AUDIO;
331
            st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, tmp);
332
            break;
333
        case 2:
334
            st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE;
335
            st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp);
336
            break;
337
        case 3:
338
            st->codec->codec_type = AVMEDIA_TYPE_DATA;
339
            break;
340
        default:
341
            av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class);
342
            return -1;
343
    }
344
    if(class<3 && st->codec->codec_id == CODEC_ID_NONE)
345
        av_log(s, AV_LOG_ERROR, "Unknown codec tag '0x%04x' for stream number %d\n",
346
               (unsigned int)tmp, stream_id);
347

    
348
    GET_V(stc->time_base_id    , tmp < nut->time_base_count);
349
    GET_V(stc->msb_pts_shift   , tmp < 16);
350
    stc->max_pts_distance= ff_get_v(bc);
351
    GET_V(stc->decode_delay    , tmp < 1000); //sanity limit, raise this if Moore's law is true
352
    st->codec->has_b_frames= stc->decode_delay;
353
    ff_get_v(bc); //stream flags
354

    
355
    GET_V(st->codec->extradata_size, tmp < (1<<30));
356
    if(st->codec->extradata_size){
357
        st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE);
358
        avio_read(bc, st->codec->extradata, st->codec->extradata_size);
359
    }
360

    
361
    if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO){
362
        GET_V(st->codec->width , tmp > 0)
363
        GET_V(st->codec->height, tmp > 0)
364
        st->sample_aspect_ratio.num= ff_get_v(bc);
365
        st->sample_aspect_ratio.den= ff_get_v(bc);
366
        if((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)){
367
            av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den);
368
            return -1;
369
        }
370
        ff_get_v(bc); /* csp type */
371
    }else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO){
372
        GET_V(st->codec->sample_rate , tmp > 0)
373
        ff_get_v(bc); // samplerate_den
374
        GET_V(st->codec->channels, tmp > 0)
375
    }
376
    if(skip_reserved(bc, end) || get_checksum(bc)){
377
        av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id);
378
        return -1;
379
    }
380
    stc->time_base= &nut->time_base[stc->time_base_id];
381
    av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den);
382
    return 0;
383
}
384

    
385
static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){
386
    int flag = 0, i;
387
    for (i=0; ff_nut_dispositions[i].flag; ++i) {
388
        if (!strcmp(ff_nut_dispositions[i].str, value))
389
            flag = ff_nut_dispositions[i].flag;
390
    }
391
    if (!flag)
392
        av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value);
393
    for (i = 0; i < avf->nb_streams; ++i)
394
        if (stream_id == i || stream_id == -1)
395
            avf->streams[i]->disposition |= flag;
396
}
397

    
398
static int decode_info_header(NUTContext *nut){
399
    AVFormatContext *s= nut->avf;
400
    AVIOContext *bc = s->pb;
401
    uint64_t tmp, chapter_start, chapter_len;
402
    unsigned int stream_id_plus1, count;
403
    int chapter_id, i;
404
    int64_t value, end;
405
    char name[256], str_value[1024], type_str[256];
406
    const char *type;
407
    AVChapter *chapter= NULL;
408
    AVStream *st= NULL;
409
    AVMetadata **metadata = NULL;
410

    
411
    end= get_packetheader(nut, bc, 1, INFO_STARTCODE);
412
    end += url_ftell(bc);
413

    
414
    GET_V(stream_id_plus1, tmp <= s->nb_streams)
415
    chapter_id   = get_s(bc);
416
    chapter_start= ff_get_v(bc);
417
    chapter_len  = ff_get_v(bc);
418
    count        = ff_get_v(bc);
419

    
420
    if(chapter_id && !stream_id_plus1){
421
        int64_t start= chapter_start / nut->time_base_count;
422
        chapter= ff_new_chapter(s, chapter_id,
423
                                nut->time_base[chapter_start % nut->time_base_count],
424
                                start, start + chapter_len, NULL);
425
        metadata = &chapter->metadata;
426
    } else if(stream_id_plus1) {
427
        st= s->streams[stream_id_plus1 - 1];
428
        metadata = &st->metadata;
429
    } else
430
        metadata = &s->metadata;
431

    
432
    for(i=0; i<count; i++){
433
        get_str(bc, name, sizeof(name));
434
        value= get_s(bc);
435
        if(value == -1){
436
            type= "UTF-8";
437
            get_str(bc, str_value, sizeof(str_value));
438
        }else if(value == -2){
439
            get_str(bc, type_str, sizeof(type_str));
440
            type= type_str;
441
            get_str(bc, str_value, sizeof(str_value));
442
        }else if(value == -3){
443
            type= "s";
444
            value= get_s(bc);
445
        }else if(value == -4){
446
            type= "t";
447
            value= ff_get_v(bc);
448
        }else if(value < -4){
449
            type= "r";
450
            get_s(bc);
451
        }else{
452
            type= "v";
453
        }
454

    
455
        if (stream_id_plus1 > s->nb_streams) {
456
            av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n");
457
            continue;
458
        }
459

    
460
        if(!strcmp(type, "UTF-8")){
461
            if(chapter_id==0 && !strcmp(name, "Disposition")) {
462
                set_disposition_bits(s, str_value, stream_id_plus1 - 1);
463
                continue;
464
            }
465
            if(metadata && strcasecmp(name,"Uses")
466
               && strcasecmp(name,"Depends") && strcasecmp(name,"Replaces"))
467
                av_metadata_set2(metadata, name, str_value, 0);
468
        }
469
    }
470

    
471
    if(skip_reserved(bc, end) || get_checksum(bc)){
472
        av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n");
473
        return -1;
474
    }
475
    return 0;
476
}
477

    
478
static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){
479
    AVFormatContext *s= nut->avf;
480
    AVIOContext *bc = s->pb;
481
    int64_t end, tmp;
482

    
483
    nut->last_syncpoint_pos= url_ftell(bc)-8;
484

    
485
    end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE);
486
    end += url_ftell(bc);
487

    
488
    tmp= ff_get_v(bc);
489
    *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc);
490
    if(*back_ptr < 0)
491
        return -1;
492

    
493
    ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count);
494

    
495
    if(skip_reserved(bc, end) || get_checksum(bc)){
496
        av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n");
497
        return -1;
498
    }
499

    
500
    *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE;
501
    ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts);
502

    
503
    return 0;
504
}
505

    
506
static int find_and_decode_index(NUTContext *nut){
507
    AVFormatContext *s= nut->avf;
508
    AVIOContext *bc = s->pb;
509
    uint64_t tmp, end;
510
    int i, j, syncpoint_count;
511
    int64_t filesize= url_fsize(bc);
512
    int64_t *syncpoints;
513
    int8_t *has_keyframe;
514
    int ret= -1;
515

    
516
    avio_seek(bc, filesize-12, SEEK_SET);
517
    avio_seek(bc, filesize-avio_rb64(bc), SEEK_SET);
518
    if(avio_rb64(bc) != INDEX_STARTCODE){
519
        av_log(s, AV_LOG_ERROR, "no index at the end\n");
520
        return -1;
521
    }
522

    
523
    end= get_packetheader(nut, bc, 1, INDEX_STARTCODE);
524
    end += url_ftell(bc);
525

    
526
    ff_get_v(bc); //max_pts
527
    GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0)
528
    syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count);
529
    has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1));
530
    for(i=0; i<syncpoint_count; i++){
531
        syncpoints[i] = ff_get_v(bc);
532
        if(syncpoints[i] <= 0)
533
            goto fail;
534
        if(i)
535
            syncpoints[i] += syncpoints[i-1];
536
    }
537

    
538
    for(i=0; i<s->nb_streams; i++){
539
        int64_t last_pts= -1;
540
        for(j=0; j<syncpoint_count;){
541
            uint64_t x= ff_get_v(bc);
542
            int type= x&1;
543
            int n= j;
544
            x>>=1;
545
            if(type){
546
                int flag= x&1;
547
                x>>=1;
548
                if(n+x >= syncpoint_count + 1){
549
                    av_log(s, AV_LOG_ERROR, "index overflow A\n");
550
                    goto fail;
551
                }
552
                while(x--)
553
                    has_keyframe[n++]= flag;
554
                has_keyframe[n++]= !flag;
555
            }else{
556
                while(x != 1){
557
                    if(n>=syncpoint_count + 1){
558
                        av_log(s, AV_LOG_ERROR, "index overflow B\n");
559
                        goto fail;
560
                    }
561
                    has_keyframe[n++]= x&1;
562
                    x>>=1;
563
                }
564
            }
565
            if(has_keyframe[0]){
566
                av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n");
567
                goto fail;
568
            }
569
            assert(n<=syncpoint_count+1);
570
            for(; j<n && j<syncpoint_count; j++){
571
                if(has_keyframe[j]){
572
                    uint64_t B, A= ff_get_v(bc);
573
                    if(!A){
574
                        A= ff_get_v(bc);
575
                        B= ff_get_v(bc);
576
                        //eor_pts[j][i] = last_pts + A + B
577
                    }else
578
                        B= 0;
579
                    av_add_index_entry(
580
                        s->streams[i],
581
                        16*syncpoints[j-1],
582
                        last_pts + A,
583
                        0,
584
                        0,
585
                        AVINDEX_KEYFRAME);
586
                    last_pts += A + B;
587
                }
588
            }
589
        }
590
    }
591

    
592
    if(skip_reserved(bc, end) || get_checksum(bc)){
593
        av_log(s, AV_LOG_ERROR, "index checksum mismatch\n");
594
        goto fail;
595
    }
596
    ret= 0;
597
fail:
598
    av_free(syncpoints);
599
    av_free(has_keyframe);
600
    return ret;
601
}
602

    
603
static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap)
604
{
605
    NUTContext *nut = s->priv_data;
606
    AVIOContext *bc = s->pb;
607
    int64_t pos;
608
    int initialized_stream_count;
609

    
610
    nut->avf= s;
611

    
612
    /* main header */
613
    pos=0;
614
    do{
615
        pos= find_startcode(bc, MAIN_STARTCODE, pos)+1;
616
        if (pos<0+1){
617
            av_log(s, AV_LOG_ERROR, "No main startcode found.\n");
618
            return AVERROR_INVALIDDATA;
619
        }
620
    }while(decode_main_header(nut) < 0);
621

    
622
    /* stream headers */
623
    pos=0;
624
    for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){
625
        pos= find_startcode(bc, STREAM_STARTCODE, pos)+1;
626
        if (pos<0+1){
627
            av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n");
628
            return AVERROR_INVALIDDATA;
629
        }
630
        if(decode_stream_header(nut) >= 0)
631
            initialized_stream_count++;
632
    }
633

    
634
    /* info headers */
635
    pos=0;
636
    for(;;){
637
        uint64_t startcode= find_any_startcode(bc, pos);
638
        pos= url_ftell(bc);
639

    
640
        if(startcode==0){
641
            av_log(s, AV_LOG_ERROR, "EOF before video frames\n");
642
            return AVERROR_INVALIDDATA;
643
        }else if(startcode == SYNCPOINT_STARTCODE){
644
            nut->next_startcode= startcode;
645
            break;
646
        }else if(startcode != INFO_STARTCODE){
647
            continue;
648
        }
649

    
650
        decode_info_header(nut);
651
    }
652

    
653
    s->data_offset= pos-8;
654

    
655
    if(!url_is_streamed(bc)){
656
        int64_t orig_pos= url_ftell(bc);
657
        find_and_decode_index(nut);
658
        avio_seek(bc, orig_pos, SEEK_SET);
659
    }
660
    assert(nut->next_startcode == SYNCPOINT_STARTCODE);
661

    
662
    ff_metadata_conv_ctx(s, NULL, ff_nut_metadata_conv);
663

    
664
    return 0;
665
}
666

    
667
static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){
668
    AVFormatContext *s= nut->avf;
669
    AVIOContext *bc = s->pb;
670
    StreamContext *stc;
671
    int size, flags, size_mul, pts_delta, i, reserved_count;
672
    uint64_t tmp;
673

    
674
    if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){
675
        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);
676
        return AVERROR_INVALIDDATA;
677
    }
678

    
679
    flags          = nut->frame_code[frame_code].flags;
680
    size_mul       = nut->frame_code[frame_code].size_mul;
681
    size           = nut->frame_code[frame_code].size_lsb;
682
    *stream_id     = nut->frame_code[frame_code].stream_id;
683
    pts_delta      = nut->frame_code[frame_code].pts_delta;
684
    reserved_count = nut->frame_code[frame_code].reserved_count;
685
    *header_idx    = nut->frame_code[frame_code].header_idx;
686

    
687
    if(flags & FLAG_INVALID)
688
        return AVERROR_INVALIDDATA;
689
    if(flags & FLAG_CODED)
690
        flags ^= ff_get_v(bc);
691
    if(flags & FLAG_STREAM_ID){
692
        GET_V(*stream_id, tmp < s->nb_streams)
693
    }
694
    stc= &nut->stream[*stream_id];
695
    if(flags&FLAG_CODED_PTS){
696
        int coded_pts= ff_get_v(bc);
697
//FIXME check last_pts validity?
698
        if(coded_pts < (1<<stc->msb_pts_shift)){
699
            *pts=ff_lsb2full(stc, coded_pts);
700
        }else
701
            *pts=coded_pts - (1<<stc->msb_pts_shift);
702
    }else
703
        *pts= stc->last_pts + pts_delta;
704
    if(flags&FLAG_SIZE_MSB){
705
        size += size_mul*ff_get_v(bc);
706
    }
707
    if(flags&FLAG_MATCH_TIME)
708
        get_s(bc);
709
    if(flags&FLAG_HEADER_IDX)
710
        *header_idx= ff_get_v(bc);
711
    if(flags&FLAG_RESERVED)
712
        reserved_count= ff_get_v(bc);
713
    for(i=0; i<reserved_count; i++)
714
        ff_get_v(bc);
715

    
716
    if(*header_idx >= (unsigned)nut->header_count){
717
        av_log(s, AV_LOG_ERROR, "header_idx invalid\n");
718
        return AVERROR_INVALIDDATA;
719
    }
720
    if(size > 4096)
721
        *header_idx=0;
722
    size -= nut->header_len[*header_idx];
723

    
724
    if(flags&FLAG_CHECKSUM){
725
        avio_rb32(bc); //FIXME check this
726
    }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){
727
        av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n");
728
        return AVERROR_INVALIDDATA;
729
    }
730

    
731
    stc->last_pts= *pts;
732
    stc->last_flags= flags;
733

    
734
    return size;
735
}
736

    
737
static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){
738
    AVFormatContext *s= nut->avf;
739
    AVIOContext *bc = s->pb;
740
    int size, stream_id, discard;
741
    int64_t pts, last_IP_pts;
742
    StreamContext *stc;
743
    uint8_t header_idx;
744

    
745
    size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code);
746
    if(size < 0)
747
        return size;
748

    
749
    stc= &nut->stream[stream_id];
750

    
751
    if (stc->last_flags & FLAG_KEY)
752
        stc->skip_until_key_frame=0;
753

    
754
    discard= s->streams[ stream_id ]->discard;
755
    last_IP_pts= s->streams[ stream_id ]->last_IP_pts;
756
    if(  (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY))
757
       ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts)
758
       || discard >= AVDISCARD_ALL
759
       || stc->skip_until_key_frame){
760
        avio_seek(bc, size, SEEK_CUR);
761
        return 1;
762
    }
763

    
764
    av_new_packet(pkt, size + nut->header_len[header_idx]);
765
    memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]);
766
    pkt->pos= url_ftell(bc); //FIXME
767
    avio_read(bc, pkt->data + nut->header_len[header_idx], size);
768

    
769
    pkt->stream_index = stream_id;
770
    if (stc->last_flags & FLAG_KEY)
771
        pkt->flags |= AV_PKT_FLAG_KEY;
772
    pkt->pts = pts;
773

    
774
    return 0;
775
}
776

    
777
static int nut_read_packet(AVFormatContext *s, AVPacket *pkt)
778
{
779
    NUTContext *nut = s->priv_data;
780
    AVIOContext *bc = s->pb;
781
    int i, frame_code=0, ret, skip;
782
    int64_t ts, back_ptr;
783

    
784
    for(;;){
785
        int64_t pos= url_ftell(bc);
786
        uint64_t tmp= nut->next_startcode;
787
        nut->next_startcode=0;
788

    
789
        if(tmp){
790
            pos-=8;
791
        }else{
792
            frame_code = avio_r8(bc);
793
            if(url_feof(bc))
794
                return -1;
795
            if(frame_code == 'N'){
796
                tmp= frame_code;
797
                for(i=1; i<8; i++)
798
                    tmp = (tmp<<8) + avio_r8(bc);
799
            }
800
        }
801
        switch(tmp){
802
        case MAIN_STARTCODE:
803
        case STREAM_STARTCODE:
804
        case INDEX_STARTCODE:
805
            skip= get_packetheader(nut, bc, 0, tmp);
806
            avio_seek(bc, skip, SEEK_CUR);
807
            break;
808
        case INFO_STARTCODE:
809
            if(decode_info_header(nut)<0)
810
                goto resync;
811
            break;
812
        case SYNCPOINT_STARTCODE:
813
            if(decode_syncpoint(nut, &ts, &back_ptr)<0)
814
                goto resync;
815
            frame_code = avio_r8(bc);
816
        case 0:
817
            ret= decode_frame(nut, pkt, frame_code);
818
            if(ret==0)
819
                return 0;
820
            else if(ret==1) //ok but discard packet
821
                break;
822
        default:
823
resync:
824
av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos);
825
            tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1);
826
            if(tmp==0)
827
                return AVERROR_INVALIDDATA;
828
av_log(s, AV_LOG_DEBUG, "sync\n");
829
            nut->next_startcode= tmp;
830
        }
831
    }
832
}
833

    
834
static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){
835
    NUTContext *nut = s->priv_data;
836
    AVIOContext *bc = s->pb;
837
    int64_t pos, pts, back_ptr;
838
av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit);
839

    
840
    pos= *pos_arg;
841
    do{
842
        pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1;
843
        if(pos < 1){
844
            assert(nut->next_startcode == 0);
845
            av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n");
846
            return AV_NOPTS_VALUE;
847
        }
848
    }while(decode_syncpoint(nut, &pts, &back_ptr) < 0);
849
    *pos_arg = pos-1;
850
    assert(nut->last_syncpoint_pos == *pos_arg);
851

    
852
    av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr );
853
    if     (stream_index == -1) return pts;
854
    else if(stream_index == -2) return back_ptr;
855

    
856
assert(0);
857
}
858

    
859
static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){
860
    NUTContext *nut = s->priv_data;
861
    AVStream *st= s->streams[stream_index];
862
    Syncpoint dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE};
863
    Syncpoint nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE};
864
    Syncpoint *sp, *next_node[2]= {&nopts_sp, &nopts_sp};
865
    int64_t pos, pos2, ts;
866
    int i;
867

    
868
    if(st->index_entries){
869
        int index= av_index_search_timestamp(st, pts, flags);
870
        if(index<0)
871
            return -1;
872

    
873
        pos2= st->index_entries[index].pos;
874
        ts  = st->index_entries[index].timestamp;
875
    }else{
876
        av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp,
877
                     (void **) next_node);
878
        av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos,
879
                                                    next_node[0]->ts , next_node[1]->ts);
880
        pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos,
881
                                            next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp);
882

    
883
        if(!(flags & AVSEEK_FLAG_BACKWARD)){
884
            dummy.pos= pos+16;
885
            next_node[1]= &nopts_sp;
886
            av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
887
                         (void **) next_node);
888
            pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos     , next_node[1]->pos, next_node[1]->pos,
889
                                                next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp);
890
            if(pos2>=0)
891
                pos= pos2;
892
            //FIXME dir but I think it does not matter
893
        }
894
        dummy.pos= pos;
895
        sp= av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp,
896
                         NULL);
897

    
898
        assert(sp);
899
        pos2= sp->back_ptr  - 15;
900
    }
901
    av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2);
902
    pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2);
903
    avio_seek(s->pb, pos, SEEK_SET);
904
    av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos);
905
    if(pos2 > pos || pos2 + 15 < pos){
906
        av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n");
907
    }
908
    for(i=0; i<s->nb_streams; i++)
909
        nut->stream[i].skip_until_key_frame=1;
910

    
911
    return 0;
912
}
913

    
914
static int nut_read_close(AVFormatContext *s)
915
{
916
    NUTContext *nut = s->priv_data;
917
    int i;
918

    
919
    av_freep(&nut->time_base);
920
    av_freep(&nut->stream);
921
    ff_nut_free_sp(nut);
922
    for(i = 1; i < nut->header_count; i++)
923
        av_freep(&nut->header[i]);
924

    
925
    return 0;
926
}
927

    
928
#if CONFIG_NUT_DEMUXER
929
AVInputFormat ff_nut_demuxer = {
930
    "nut",
931
    NULL_IF_CONFIG_SMALL("NUT format"),
932
    sizeof(NUTContext),
933
    nut_probe,
934
    nut_read_header,
935
    nut_read_packet,
936
    nut_read_close,
937
    read_seek,
938
    .extensions = "nut",
939
    .codec_tag = (const AVCodecTag * const []) { ff_codec_bmp_tags, ff_nut_video_tags, ff_codec_wav_tags, ff_nut_subtitle_tags, 0 },
940
};
941
#endif