src/matroska.c

   1 /*****************************************************************************
   2  * matroska.c:
   3  *****************************************************************************
   4  * Copyright (C) 2005 x264 project
   5  *
   6  * Authors: Mike Matsnev
   7  *          Nathan Caldwell
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23 #include "config.h"
  24 #include "libmkv.h"
  25 #include "matroska.h"
  26 #include "md5.h"
  27
  28 #include <sys/time.h>
  29
  30 #define RESERVED_SEEKHEAD 0x100
  31 /* 256 bytes should be enough room for our Seek entries. */
  32 #define RESERVED_CHAPTERS 0x1000
  33 /* 4096 bytes, hopefully enough for Chapters. */
  34
  35 int mk_seekFile(mk_Writer *w, uint64_t pos)
  36 {
  37         if (fseek(w->fp, pos, SEEK_SET))
  38                 return -1;
  39
  40         w->f_pos = pos;
  41
  42         if (pos > w->f_eof)
  43                 w->f_eof = pos;
  44
  45         return 0;
  46 }
  47
  48 char *mk_laceXiph(uint64_t *sizes, uint8_t num_frames,
  49                                   uint64_t *output_size)
  50 {
  51         unsigned i, j;
  52         uint64_t offset = 0;
  53         uint64_t alloc_size = num_frames * 6;   /* Complete guess. It gets realloc'd
  54                                                                                          * below if we need more space, though.
  55                                                                                          */
  56         char *laced = calloc(alloc_size, sizeof(*laced));
  57         if (laced == NULL)
  58                 return NULL;
  59
  60         laced[offset++] = num_frames;
  61         for (i = 0; i < num_frames; i++) {
  62                 for (j = sizes[i]; j >= 255; j -= 255) {
  63                         laced[offset++] = 255;
  64                         if (offset + 1 >= alloc_size) {
  65                                 int avg_sz = offset / (i - 1);  /* Compute approximate average bytes/frame */
  66                                 alloc_size += avg_sz * (num_frames - i);
  67                                                                 /* Sum average so far and number of frames left
  68                                                                  * with alloc'd size
  69                                                                  */
  70                                 if ((laced = realloc(laced, alloc_size)) == NULL)
  71                                         return NULL;
  72                         }
  73                 }
  74                 laced[offset++] = j;
  75         }
  76
  77         if (output_size != NULL)
  78                 *output_size = offset;
  79
  80         return laced;
  81 }
  82
  83 mk_Writer *mk_createWriter(const char *filename, int64_t timescale,
  84                                                    uint8_t vlc_compat)
  85 {
  86         mk_Writer *w = calloc(1, sizeof(*w));
  87         struct timeval tv;
  88
  89         if (w == NULL)
  90                 return NULL;
  91
  92         w->root = mk_createContext(w, NULL, 0);
  93         if (w->root == NULL) {
  94                 free(w);
  95                 return NULL;
  96         }
  97
  98         /* Cues */
  99         if ((w->cues = mk_createContext(w, w->root, MATROSKA_ID_CUES)) == NULL)
 100         {
 101                 mk_destroyContexts(w);
 102                 free(w);
 103                 return NULL;
 104         }
 105
 106         /* Clusters SeekHead */
 107         if ((w->cluster.seekhead = mk_createContext(w, w->root, MATROSKA_ID_SEEKHEAD)) == NULL)
 108         {
 109                 mk_destroyContexts(w);
 110                 free(w);
 111                 return NULL;
 112         }
 113
 114         w->fp = fopen(filename, "wb");
 115         if (w->fp == NULL) {
 116                 mk_destroyContexts(w);
 117                 free(w);
 118                 return NULL;
 119         }
 120
 121         gettimeofday( &tv, NULL );
 122         srandom(tv.tv_sec ^ tv.tv_usec);
 123
 124         w->timescale = timescale;
 125         w->vlc_compat = vlc_compat;
 126
 127         return w;
 128 }
 129
 130 int mk_writeHeader(mk_Writer *w, const char *writingApp)
 131 {
 132         mk_Context *c;
 133         int64_t offset = 0;
 134
 135         if (w->wrote_header)
 136                 return -1;
 137
 138         md5_starts(&w->segment_md5);    /* Initalize MD5 */
 139
 140         CHECK(mk_writeEbmlHeader(w, "matroska", MATROSKA_VERSION, MATROSKA_VERSION));
 141
 142         /* Segment */
 143         if ((c = mk_createContext(w, w->root, MATROSKA_ID_SEGMENT)) == NULL)
 144                 return -1;
 145         CHECK(mk_flushContextID(c));
 146         w->segment_ptr = c->d_cur;
 147         CHECK(mk_closeContext(c, &w->segment_ptr));
 148
 149         if (w->vlc_compat) {
 150                 CHECK(mk_writeVoid(w->root, RESERVED_SEEKHEAD));        /* Reserved space for SeekHead */
 151                 CHECK(mk_writeVoid(w->root, RESERVED_CHAPTERS));        /* Reserved space for Chapters */
 152         } else {
 153                 w->seek_data.seekhead = 0x80000000;
 154                 CHECK(mk_writeSeekHead(w, &w->seekhead_ptr));
 155                 w->seek_data.seekhead = 0;
 156         }
 157
 158         if ((c = mk_createContext(w, w->root, MATROSKA_ID_INFO)) == NULL)       /* SegmentInfo */
 159                 return -1;
 160         w->seek_data.segmentinfo = w->root->d_cur - w->segment_ptr;
 161         CHECK(mk_writeVoid(c, 16));     /* Reserve space for a SegmentUID, to be written it later. */
 162         CHECK(mk_writeStr(c, MATROSKA_ID_MUXINGAPP, PACKAGE_STRING));   /* MuxingApp */
 163         CHECK(mk_writeStr(c, MATROSKA_ID_WRITINGAPP, writingApp));      /* WritingApp */
 164         CHECK(mk_writeUInt(c, MATROSKA_ID_TIMECODESCALE, w->timescale));        /* TimecodeScale */
 165         CHECK(mk_writeFloat(c, MATROSKA_ID_DURATION, 0));       /* Duration */
 166         w->duration_ptr = c->d_cur - 4;
 167         CHECK(mk_closeContext(c, &offset));
 168         w->duration_ptr += offset;
 169         w->segmentuid_ptr = offset;
 170
 171         w->seek_data.tracks = w->root->d_cur - w->segment_ptr;
 172
 173         if (w->tracks)
 174                 CHECK(mk_closeContext(w->tracks, 0));
 175
 176         CHECK(mk_flushContextData(w->root));
 177
 178         w->wrote_header = 1;
 179         w->def_duration = w->tracks_arr[0]->default_duration;
 180         return 0;
 181 }
 182
 183 static int mk_closeCluster(mk_Writer *w)
 184 {
 185         if (w->cluster.context == NULL)
 186                 return 0;
 187         w->cluster.count++;
 188         CHECK(mk_closeContext(w->cluster.context, 0));
 189         w->cluster.context = NULL;
 190         CHECK(mk_flushContextData(w->root));
 191
 192         return 0;
 193 }
 194
 195 int mk_flushFrame(mk_Writer *w, mk_Track *track)
 196 {
 197         mk_Context *c, *tp;
 198         int64_t delta, ref = 0;
 199         unsigned fsize, bgsize;
 200         uint8_t flags, c_delta[2];
 201         int i;
 202         char *laced = NULL;
 203         uint64_t length = 0;
 204         uint64_t block_duration = 0;
 205
 206         if (!track->in_frame)
 207                 return 0;
 208
 209         delta = track->frame.timecode / w->timescale - w->cluster.tc_scaled;
 210         block_duration = track->frame.duration / w->timescale;
 211         /* If switch rapidly back-and-forth between tracks with drastically different timecodes
 212          * this causes a new cluster to be written each time a switch is made. This causes
 213          * unnecessary overhead.
 214          */
 215
 216         if (delta > 20000ll || delta < -20000ll)
 217                 CHECK(mk_closeCluster(w));
 218
 219         if (w->cluster.context == NULL) {
 220                 w->cluster.tc_scaled = track->frame.timecode / w->timescale;
 221                 /* Cluster */
 222                 w->cluster.context = mk_createContext(w, w->root, MATROSKA_ID_CLUSTER);
 223                 if (w->cluster.context == NULL)
 224                         return -1;
 225
 226                 w->cluster.pointer = w->f_pos - w->segment_ptr;
 227
 228                 /* Cluster SeekEntry */
 229                 CHECK(mk_writeSeek(w, w->cluster.seekhead, MATROSKA_ID_CLUSTER,
 230                                                    w->cluster.pointer));
 231
 232                 /* Cluster Timecode */
 233                 CHECK(mk_writeUInt(w->cluster.context, MATROSKA_ID_CLUSTERTIMECODE, w->cluster.tc_scaled));
 234
 235                 delta = 0;
 236                 w->cluster.block_count = 0;
 237         }
 238
 239         /* Calculate the encoded lacing sizes. */
 240         switch (track->frame.lacing) {
 241                 case MK_LACING_XIPH:
 242                         laced = mk_laceXiph(track->frame.lacing_sizes,
 243                                                                 track->frame.lacing_num_frames, &length);
 244                         break;
 245                 case MK_LACING_EBML:
 246                 {
 247                         uint64_t u_size = 0;
 248                         /* Add one below for the frame count. */
 249                         length += mk_ebmlSizeSize(track->frame.lacing_sizes[0]) + 1;
 250                         for (i = 1; i < track->frame.lacing_num_frames; i++) {
 251                                 u_size = llabs(track->frame.lacing_sizes[i] -
 252                                                            track->frame.lacing_sizes[i - 1]);
 253                                 /* Shift by one so we get the right size for a signed number. */
 254                                 length += mk_ebmlSizeSize((u_size) << 1);
 255                         }
 256                         break;
 257                 }
 258                 case MK_LACING_FIXED:
 259                 {
 260                         laced = calloc(1, sizeof(*laced));
 261                         laced[0] = track->frame.lacing_num_frames;
 262                         ++length;
 263                         break;
 264                 }
 265                 default:
 266                         break;
 267         }
 268
 269         fsize = track->frame.data ? track->frame.data->d_cur : 0;
 270         bgsize = fsize + 4 + mk_ebmlSizeSize(fsize + 4 + length) + 1 + length;
 271         if (!track->frame.keyframe) {
 272                 ref = track->prev_frame_tc_scaled - w->cluster.tc_scaled - delta;
 273                 bgsize += 1 + 1 + mk_ebmlSIntSize(ref);
 274         }
 275         if (block_duration > 0) /* BlockDuration */
 276         {
 277                 bgsize += 1 + 1 + mk_ebmlUIntSize(block_duration);
 278         }
 279
 280         CHECK(mk_writeID(w->cluster.context, MATROSKA_ID_BLOCKGROUP));  /* BlockGroup */
 281         CHECK(mk_writeSize(w->cluster.context, bgsize));
 282         CHECK(mk_writeID(w->cluster.context, MATROSKA_ID_BLOCK));       /* Block */
 283         CHECK(mk_writeSize(w->cluster.context, fsize + 4 + length));    /* BlockSize */
 284         CHECK(mk_writeSize(w->cluster.context, track->track_id));       /* track number */
 285
 286         w->cluster.block_count++;
 287
 288         c_delta[0] = delta >> 8;
 289         c_delta[1] = delta;
 290         /* Timecode relative to Cluster. */
 291         CHECK(mk_appendContextData(w->cluster.context, c_delta, 2));
 292
 293 /*      flags = ( track->frame.keyframe << 8 ) | track->frame.lacing; */
 294         flags = track->frame.lacing << 1;       /* Flags: Bit 5-6 describe what type of lacing to use. */
 295         CHECK(mk_appendContextData(w->cluster.context, &flags, 1));
 296         if (track->frame.lacing) {
 297                 if (track->frame.lacing == MK_LACING_EBML) {
 298                         /* Number of frames in lace - 1 */
 299                         CHECK(mk_appendContextData(w->cluster.context, &track->frame.lacing_num_frames, 1));
 300                         /* Size of 1st frame. */
 301                         CHECK(mk_writeSize(w->cluster.context, track->frame.lacing_sizes[0]));
 302                         for (i = 1; i < track->frame.lacing_num_frames; i++) {
 303                                 /* Size difference between previous size and this size. */
 304                                 CHECK(mk_writeSSize(w->cluster.context, track->frame.lacing_sizes[i] - track->frame.lacing_sizes[i - 1]));
 305                         }
 306                 } else if (length > 0 && laced != NULL) {
 307                         CHECK(mk_appendContextData(w->cluster.context, laced, length));
 308                         free(laced);
 309                         laced = NULL;
 310                 }
 311         }
 312
 313         if (track->frame.data) {
 314                 CHECK(mk_appendContextData(w->cluster.context, track->frame.data->data,
 315                                                                    track->frame.data->d_cur));
 316                 track->frame.data->d_cur = 0;
 317         }
 318         if (!track->frame.keyframe)             /* ReferenceBlock */
 319                 CHECK(mk_writeSInt(w->cluster.context, MATROSKA_ID_REFERENCEBLOCK, ref));
 320
 321         if (block_duration > 0) /* BlockDuration */
 322                 CHECK(mk_writeUInt(w->cluster.context, 0x9b, block_duration));
 323
 324         /* This may get a little out of hand, but it seems sane enough for now. */
 325         if (track->frame.keyframe && (track->track_type == MK_TRACK_VIDEO)) {
 326 /*      if (track->frame.keyframe && (track->track_type & MK_TRACK_VIDEO) && ((track->prev_cue_pos + 3*CLSIZE) <= w->f_pos || track->frame.timecode == 0)) { */
 327                 /* CuePoint */
 328                 if ((c = mk_createContext(w, w->cues, MATROSKA_ID_CUEPOINT)) == NULL)
 329                         return -1;
 330                 /* CueTime */
 331                 CHECK(mk_writeUInt(c, MATROSKA_ID_CUETIME, (track->frame.timecode / w->timescale)));
 332
 333                 /* CueTrackPositions */
 334                 if ((tp = mk_createContext(w, c, MATROSKA_ID_CUETRACKPOSITIONS)) == NULL)
 335                         return -1;
 336                 /* CueTrack */
 337                 CHECK(mk_writeUInt(tp, MATROSKA_ID_CUETRACK, track->track_id));
 338                 /* CueClusterPosition */
 339                 CHECK(mk_writeUInt(tp, MATROSKA_ID_CUECLUSTERPOSITION, w->cluster.pointer));
 340                 /* CueBlockNumber */
 341 /*              CHECK(mk_writeUInt(c, MATROSKA_ID_CUEBLOCKNUMBER, w->cluster.block_count)); */
 342                 CHECK(mk_closeContext(tp, 0));
 343                 CHECK(mk_closeContext(c, 0));
 344                 track->prev_cue_pos = w->f_pos;
 345         }
 346
 347         track->in_frame = 0;
 348         track->prev_frame_tc_scaled = w->cluster.tc_scaled + delta;
 349
 350         /* Write a new Cluster ~ every 5MB */
 351         if (w->cluster.context->d_cur > 5 * CLSIZE)
 352                 CHECK(mk_closeCluster(w));
 353
 354         return 0;
 355 }
 356
 357 int mk_startFrame(mk_Writer *w, mk_Track *track)
 358 {
 359         if (mk_flushFrame(w, track) < 0)
 360                 return -1;
 361
 362         track->in_frame = 1;
 363         track->frame.keyframe = 0;
 364         track->frame.lacing = MK_LACING_NONE;
 365         track->frame.lacing_num_frames = 0;
 366         track->frame.lacing_sizes = NULL;
 367
 368         return 0;
 369 }
 370
 371 int mk_setFrameFlags(mk_Writer *w, mk_Track *track, int64_t timestamp,
 372                                          unsigned keyframe, uint64_t duration)
 373 {
 374         if (!track->in_frame)
 375                 return -1;
 376
 377         track->frame.timecode = timestamp;
 378         track->frame.keyframe = keyframe != 0;
 379
 380         if (track->max_frame_tc < timestamp)
 381                 track->max_frame_tc = timestamp;
 382
 383         if (duration > 0)
 384                 track->frame.duration = duration;
 385
 386         return 0;
 387 }
 388
 389 int mk_setFrameLacing(mk_Writer *w, mk_Track *track,
 390                                           mk_LacingType lacing, uint8_t num_frames,
 391                                           uint64_t sizes[])
 392 {
 393         if (!track->in_frame)
 394                 return -1;
 395         track->frame.lacing_sizes = calloc(num_frames, sizeof(*sizes));
 396
 397         track->frame.lacing = lacing;
 398         track->frame.lacing_num_frames = num_frames;
 399         memcpy(track->frame.lacing_sizes, sizes,
 400                    num_frames * sizeof(*sizes));
 401
 402         return 0;
 403 }
 404
 405 int mk_addFrameData(mk_Writer *w, mk_Track *track, const void *data,
 406                                         unsigned size)
 407 {
 408         if (!track->in_frame)
 409                 return -1;
 410
 411         if (track->frame.data == NULL) {
 412                 if ((track->frame.data = mk_createContext(w, NULL, 0)) == NULL)
 413                         return -1;
 414         }
 415
 416         md5_update(&w->segment_md5, (unsigned char *) data, size);
 417
 418         return mk_appendContextData(track->frame.data, data, size);
 419 }
 420
 421 int mk_writeSeek(mk_Writer *w, mk_Context *c, unsigned seek_id,
 422                                  uint64_t seek_pos)
 423 {
 424         mk_Context *s;
 425
 426         if ((s = mk_createContext(w, c, MATROSKA_ID_SEEKENTRY)) == NULL)        /* Seek */
 427                 return -1;
 428         CHECK(mk_writeUInt(s, MATROSKA_ID_SEEKID, seek_id));    /* SeekID */
 429         CHECK(mk_writeUInt(s, MATROSKA_ID_SEEKPOSITION, seek_pos));     /* SeekPosition */
 430         CHECK(mk_closeContext(s, 0));
 431
 432         return 0;
 433 }
 434
 435 /* The offset of the SeekHead is returned in pointer. */
 436 int mk_writeSeekHead(mk_Writer *w, int64_t *pointer)
 437 {
 438         mk_Context *c;
 439         int64_t seekhead_ptr;
 440
 441         /* SeekHead */
 442         if ((c = mk_createContext(w, w->root, MATROSKA_ID_SEEKHEAD)) == NULL)
 443                 return -1;
 444         if (pointer != NULL)
 445                 seekhead_ptr = w->f_pos;
 446         if (w->seek_data.seekhead)
 447                 CHECK(mk_writeSeek(w, c, MATROSKA_ID_SEEKHEAD, w->seek_data.seekhead));
 448         if (w->seek_data.segmentinfo)
 449                 CHECK(mk_writeSeek(w, c, MATROSKA_ID_INFO, w->seek_data.segmentinfo));
 450         if (w->seek_data.tracks)
 451                 CHECK(mk_writeSeek(w, c, MATROSKA_ID_TRACKS, w->seek_data.tracks));
 452         if (w->seek_data.cues)
 453                 CHECK(mk_writeSeek(w, c, MATROSKA_ID_CUES, w->seek_data.cues));
 454         if (w->seek_data.attachments)
 455                 CHECK(mk_writeSeek(w, c, MATROSKA_ID_ATTACHMENTS, w->seek_data.attachments));
 456         if (w->seek_data.chapters)
 457                 CHECK(mk_writeSeek(w, c, MATROSKA_ID_CHAPTERS, w->seek_data.chapters));
 458         if (w->seek_data.tags)
 459                 CHECK(mk_writeSeek(w, c, MATROSKA_ID_TAGS, w->seek_data.tags));
 460         CHECK(mk_closeContext(c, 0));
 461
 462         if (pointer != NULL)
 463                 *pointer = seekhead_ptr;
 464
 465         return 0;
 466 }
 467
 468 int mk_close(mk_Writer *w)
 469 {
 470         int i, ret = 0;
 471         mk_Track *tk;
 472         int64_t max_frame_tc = w->tracks_arr[0]->max_frame_tc;
 473         uint64_t segment_size = 0;
 474         unsigned char c_size[8];
 475         unsigned char segment_uid[16];
 476
 477         md5_finish(&w->segment_md5, segment_uid);
 478
 479         for (i = w->num_tracks - 1; i >= 0; i--) {
 480                 tk = w->tracks_arr[i];
 481                 w->tracks_arr[i] = NULL;
 482                 --w->num_tracks;
 483                 if (mk_flushFrame(w, tk) < 0)
 484                         ret = -1;
 485                 free(tk);
 486                 tk = NULL;
 487         }
 488
 489         if (mk_closeCluster(w) < 0)
 490                 ret = -1;
 491
 492         w->seek_data.cues = w->f_pos - w->segment_ptr;
 493         if (mk_closeContext(w->cues, 0) < 0)
 494                 ret = -1;
 495         if (mk_flushContextData(w->root) < 0)
 496                 ret = -1;
 497
 498         if (w->cluster.seekhead) {
 499                 w->seek_data.seekhead = w->f_pos - w->segment_ptr;
 500                 if (mk_closeContext(w->cluster.seekhead, 0) < 0)
 501                         ret = -1;
 502                 if (mk_flushContextData(w->root) < 0)
 503                         ret = -1;
 504         }
 505
 506         if (w->attachments != NULL) {
 507                 w->seek_data.attachments = w->f_pos - w->segment_ptr;
 508                 mk_writeAttachments(w);
 509                 if (mk_flushContextData(w->root) < 0)
 510                         ret = -1;
 511         }
 512
 513         if (w->tags != NULL) {
 514                 w->seek_data.tags = w->f_pos - w->segment_ptr;
 515                 mk_writeTags(w);
 516                 if (mk_flushContextData(w->root) < 0)
 517                         ret = -1;
 518         }
 519
 520         if (w->chapters != NULL) {
 521                 if (w->vlc_compat) {
 522                         if (mk_flushContextData(w->root) < 0)
 523                                 ret = -1;
 524                         if (mk_seekFile(w, w->segment_ptr + RESERVED_SEEKHEAD + 3) < 0)
 525                                 ret = -1;
 526                 }
 527                 w->seek_data.chapters = w->f_pos - w->segment_ptr;
 528                 mk_writeChapters(w);
 529                 if (mk_flushContextData(w->root) < 0)
 530                         ret = -1;
 531                 if (w->vlc_compat) {
 532                         if (mk_writeVoid(w->root, (RESERVED_CHAPTERS - (w->f_pos - w->segment_ptr - RESERVED_SEEKHEAD - 3))) < 0)
 533                                 ret = -1;
 534                         if (mk_flushContextData(w->root) < 0)
 535                                 ret = -1;
 536                 }
 537         }
 538
 539         if (w->wrote_header) {
 540                 if (w->vlc_compat) {
 541                         if (mk_seekFile(w, w->segment_ptr) < 0)
 542                                 ret = -1;
 543                 }
 544
 545                 if (mk_writeSeekHead(w, &w->seek_data.seekhead) < 0)
 546                         ret = -1;
 547                 w->seek_data.seekhead -= w->segment_ptr;
 548
 549                 if (w->vlc_compat) {
 550                         if (mk_flushContextData(w->root) < 0)
 551                                 ret = -1;
 552                         if (mk_writeVoid(w->root, (RESERVED_SEEKHEAD - (w->f_pos - w->segment_ptr))) < 0)
 553                                 ret = -1;
 554                 }
 555
 556                 if (mk_flushContextData(w->root) < 0)
 557                         ret = -1;
 558
 559                 if (!w->vlc_compat) {
 560                         int i = w->seek_data.segmentinfo;
 561                         w->seek_data.segmentinfo = 0;
 562                         w->seek_data.tracks = 0;
 563                         w->seek_data.cues = 0;
 564                         w->seek_data.chapters = 0;
 565                         w->seek_data.attachments = 0;
 566                         w->seek_data.tags = 0;
 567                         if (mk_seekFile(w, w->segment_ptr) < 0)
 568                                 ret = -1;
 569                         if (mk_writeSeekHead(w, NULL) < 0 || mk_flushContextData(w->root) < 0)
 570                                 ret = -1;
 571                         // The conditional below is easier to understand, but incorrect
 572                         // because f_pos is unsigned and causes the lhs to be evaluated
 573                         // as an unsigned quantity.
 574                         // if (((i + w->segment_ptr) - w->f_pos - 2) > 1)
 575                         if ((i + w->segment_ptr) > (w->f_pos + 3))
 576                                 if (mk_writeVoid(w->root, (i + w->segment_ptr) - w->f_pos - 2) < 0
 577                                         || mk_flushContextData(w->root) < 0)
 578                                         ret = -1;
 579                 }
 580
 581                 if (mk_seekFile(w, w->duration_ptr) < 0)
 582                         ret = -1;
 583                 if (mk_writeFloatRaw(w->root,
 584                                                          (float) ((double) (max_frame_tc + w->def_duration) /
 585                                                          w->timescale)) < 0
 586                         || mk_flushContextData(w->root) < 0)
 587                         ret = -1;
 588                 if (mk_seekFile(w, w->segment_ptr - 8) < 0)
 589                         ret = -1;
 590                 segment_size = w->f_eof - w->segment_ptr;
 591                 for (i = 7; i > 0; --i)
 592                         c_size[i] = segment_size >> (8 * (7 - i));
 593                 c_size[i] = 0x01;
 594                 if (mk_appendContextData(w->root, &c_size, 8) < 0 ||
 595                         mk_flushContextData(w->root) < 0)
 596                         ret = -1;
 597                 if (mk_seekFile(w, w->segmentuid_ptr) < 0)
 598                         ret = -1;
 599                 if (mk_writeBin(w->root, MATROSKA_ID_SEGMENTUID, segment_uid,
 600                                                 sizeof(segment_uid)) < 0 ||
 601                         mk_flushContextData(w->root) < 0)
 602                         ret = -1;
 603         }
 604
 605         if (mk_closeContext(w->root, 0) < 0)
 606                 ret = -1;
 607         mk_destroyContexts(w);
 608         fclose(w->fp);
 609         free(w->tracks_arr);
 610         free(w);
 611
 612         return ret;
 613 }