git.sesse.net Git - vlc/blob - modules/demux/mpeg/system.c

   1 /*****************************************************************************
   2  * system.c: helper module for TS, PS and PES management
   3  *****************************************************************************
   4  * Copyright (C) 1998-2002 VideoLAN
   5  * $Id: system.c,v 1.14 2003/05/05 22:23:36 gbazin Exp $
   6  *
   7  * Authors: Christophe Massiot <massiot@via.ecp.fr>
   8  *          Michel Lespinasse <walken@via.ecp.fr>
   9  *          Benoît Steiner <benny@via.ecp.fr>
  10  *          Samuel Hocevar <sam@zoy.org>
  11  *          Henri Fallon <henri@via.ecp.fr>
  12  *
  13  * This program is free software; you can redistribute it and/or modify
  14  * it under the terms of the GNU General Public License as published by
  15  * the Free Software Foundation; either version 2 of the License, or
  16  * (at your option) any later version.
  17  *
  18  * This program is distributed in the hope that it will be useful,
  19  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  20  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  21  * GNU General Public License for more details.
  22  *
  23  * You should have received a copy of the GNU General Public License
  24  * along with this program; if not, write to the Free Software
  25  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  26  *****************************************************************************/
  27
  28 /*****************************************************************************
  29  * Preamble
  30  *****************************************************************************/
  31 #include <stdlib.h>
  32 #include <string.h>                                    /* memcpy(), memset() */
  33
  34 #include <vlc/vlc.h>
  35 #include <vlc/input.h>
  36
  37 #include "system.h"
  38
  39 /*****************************************************************************
  40  * Local prototypes
  41  *****************************************************************************/
  42 static int Activate ( vlc_object_t * );
  43
  44 static ssize_t           ReadPS  ( input_thread_t *, data_packet_t ** );
  45 static es_descriptor_t * ParsePS ( input_thread_t *, data_packet_t * );
  46 static void              DemuxPS ( input_thread_t *, data_packet_t * );
  47
  48 static ssize_t           ReadTS  ( input_thread_t *, data_packet_t ** );
  49 static void              DemuxTS ( input_thread_t *, data_packet_t *,
  50                                    psi_callback_t );
  51
  52 /*****************************************************************************
  53  * Module descriptor
  54  *****************************************************************************/
  55 vlc_module_begin();
  56     set_description( _("generic ISO 13818-1 MPEG demultiplexing") );
  57     set_capability( "mpeg-system", 100 );
  58     set_callbacks( Activate, NULL );
  59 vlc_module_end();
  60
  61 /*****************************************************************************
  62  * Activate: initializes helper functions
  63  *****************************************************************************/
  64 static int Activate ( vlc_object_t *p_this )
  65 {
  66     static mpeg_demux_t mpeg_demux =
  67                     { NULL, ReadPS, ParsePS, DemuxPS, ReadTS, DemuxTS };
  68
  69     memcpy( p_this->p_private, &mpeg_demux, sizeof( mpeg_demux ) );
  70
  71     return VLC_SUCCESS;
  72 }
  73
  74 /*
  75  * PES Packet management
  76  */
  77
  78 /*****************************************************************************
  79  * MoveChunk
  80  *****************************************************************************
  81  * Small utility function used to parse discontinuous headers safely. Copies
  82  * i_buf_len bytes of data to a buffer and returns the size copied.
  83  * It also solves some alignment problems on non-IA-32, non-PPC processors.
  84  * This is a variation on the theme of input_ext-dec.h:GetChunk().
  85  *****************************************************************************/
  86 static inline size_t MoveChunk( byte_t * p_dest, data_packet_t ** pp_data_src,
  87                                 byte_t ** pp_src, size_t i_buf_len )
  88 {
  89     size_t i_available;
  90
  91     i_available = (ptrdiff_t)((*pp_data_src)->p_payload_end - *pp_src);
  92     if( i_available >= i_buf_len )
  93     {
  94         if( p_dest != NULL )
  95             memcpy( p_dest, *pp_src, i_buf_len );
  96         *pp_src += i_buf_len;
  97         return( i_buf_len );
  98     }
  99     else
 100     {
 101         size_t i_init_len = i_buf_len;
 102
 103         do
 104         {
 105             if( p_dest != NULL )
 106                 memcpy( p_dest, *pp_src, i_available );
 107             *pp_data_src = (*pp_data_src)->p_next;
 108             i_buf_len -= i_available;
 109             p_dest += i_available;
 110             if( *pp_data_src == NULL )
 111             {
 112                 *pp_src = NULL;
 113                 return( i_init_len - i_buf_len );
 114             }
 115             *pp_src = (*pp_data_src)->p_payload_start;
 116
 117             i_available = (ptrdiff_t)((*pp_data_src)->p_payload_end - *pp_src);
 118         }
 119         while( i_available <= i_buf_len );
 120
 121         if( i_buf_len )
 122         {
 123             if( p_dest != NULL )
 124                 memcpy( p_dest, *pp_src, i_buf_len );
 125             *pp_src += i_buf_len;
 126         }
 127         return( i_init_len );
 128     }
 129 }
 130
 131 /*****************************************************************************
 132  * ParsePES
 133  *****************************************************************************
 134  * Parse a finished PES packet and analyze its header.
 135  *****************************************************************************/
 136 #define PES_HEADER_SIZE     7
 137 static void ParsePES( input_thread_t * p_input, es_descriptor_t * p_es )
 138 {
 139     data_packet_t * p_data;
 140     byte_t *        p_byte;
 141     byte_t          p_header[PES_HEADER_SIZE];
 142     int             i_done;
 143
 144 #define p_pes (p_es->p_pes)
 145
 146     /* Parse the header. The header has a variable length, but in order
 147      * to improve the algorithm, we will read the 14 bytes we may be
 148      * interested in */
 149     p_data = p_pes->p_first;
 150     p_byte = p_data->p_payload_start;
 151     i_done = 0;
 152
 153     if( MoveChunk( p_header, &p_data, &p_byte, PES_HEADER_SIZE )
 154             != PES_HEADER_SIZE )
 155     {
 156         msg_Warn( p_input, "PES packet too short to have a header" );
 157         input_DeletePES( p_input->p_method_data, p_pes );
 158         p_pes = NULL;
 159         return;
 160     }
 161
 162     /* Get the PES size if defined */
 163     p_es->i_pes_real_size = U16_AT(p_header + 4);
 164     if( p_es->i_pes_real_size )
 165     {
 166         p_es->i_pes_real_size += 6;
 167     }
 168
 169     /* First read the 6 header bytes common to all PES packets:
 170      * use them to test the PES validity */
 171     if( (p_header[0] || p_header[1] || (p_header[2] != 1)) )
 172     {
 173         /* packet_start_code_prefix != 0x000001 */
 174         msg_Err( p_input, "data loss, PES packet does not start with 000001" );
 175         input_DeletePES( p_input->p_method_data, p_pes );
 176         p_pes = NULL;
 177     }
 178     else
 179     {
 180         unsigned int i_pes_header_size, i_payload_size;
 181
 182         if ( p_es->i_pes_real_size &&
 183              (p_es->i_pes_real_size != p_pes->i_pes_size) )
 184         {
 185             /* PES_packet_length is set and != total received payload */
 186             /* Warn the decoder that the data may be corrupt. */
 187             msg_Warn( p_input, "packet corrupted, PES sizes do not match" );
 188         }
 189
 190         switch( p_header[3] )
 191         {
 192         case 0xBC:  /* Program stream map */
 193         case 0xBE:  /* Padding */
 194         case 0xBF:  /* Private stream 2 */
 195         case 0xB0:  /* ECM */
 196         case 0xB1:  /* EMM */
 197         case 0xFF:  /* Program stream directory */
 198         case 0xF2:  /* DSMCC stream */
 199         case 0xF8:  /* ITU-T H.222.1 type E stream */
 200             /* The payload begins immediately after the 6 bytes header, so
 201              * we have finished with the parsing */
 202             i_pes_header_size = 6;
 203             break;
 204
 205         default:
 206             if( (p_header[6] & 0xC0) == 0x80 )
 207             {
 208                 /* MPEG-2 : the PES header contains at least 3 more bytes. */
 209                 size_t      i_max_len;
 210                 vlc_bool_t  b_has_pts, b_has_dts;
 211                 byte_t      p_full_header[12];
 212
 213                 p_pes->b_data_alignment = p_header[6] & 0x04;
 214
 215                 i_max_len = MoveChunk( p_full_header, &p_data, &p_byte, 12 );
 216                 if( i_max_len < 2 )
 217                 {
 218                     msg_Warn( p_input,
 219                               "PES packet too short to have a MPEG-2 header" );
 220                     input_DeletePES( p_input->p_method_data,
 221                                             p_pes );
 222                     p_pes = NULL;
 223                     return;
 224                 }
 225
 226                 b_has_pts = p_full_header[0] & 0x80;
 227                 b_has_dts = p_full_header[0] & 0x40;
 228                 i_pes_header_size = p_full_header[1] + 9;
 229
 230                 /* Now parse the optional header extensions */
 231                 if( b_has_pts )
 232                 {
 233                     if( i_max_len < 7 )
 234                     {
 235                         msg_Warn( p_input,
 236                              "PES packet too short to have a MPEG-2 header" );
 237                         input_DeletePES( p_input->p_method_data,
 238                                                 p_pes );
 239                         p_pes = NULL;
 240                         return;
 241                     }
 242                     p_pes->i_pts = input_ClockGetTS( p_input, p_es->p_pgrm,
 243                     ( ((mtime_t)(p_full_header[2] & 0x0E) << 29) |
 244                       ((mtime_t)(p_full_header[3]) << 22) |
 245                       ((mtime_t)(p_full_header[4] & 0xFE) << 14) |
 246                       ((mtime_t)p_full_header[5] << 7) |
 247                       ((mtime_t)p_full_header[6] >> 1) ) );
 248
 249                     if( b_has_dts )
 250                     {
 251                         if( i_max_len < 12 )
 252                         {
 253                             msg_Warn( p_input,
 254                               "PES packet too short to have a MPEG-2 header" );
 255                             input_DeletePES( p_input->p_method_data,
 256                                                     p_pes );
 257                             p_pes = NULL;
 258                             return;
 259                         }
 260                         p_pes->i_dts = input_ClockGetTS( p_input, p_es->p_pgrm,
 261                         ( ((mtime_t)(p_full_header[7] & 0x0E) << 29) |
 262                           (((mtime_t)U16_AT(p_full_header + 8) << 14)
 263                                 - (1 << 14)) |
 264                           ((mtime_t)U16_AT(p_full_header + 10) >> 1) ) );
 265                     }
 266                 }
 267             }
 268             else
 269             {
 270                 /* Probably MPEG-1 */
 271                 vlc_bool_t      b_has_pts, b_has_dts;
 272
 273                 i_pes_header_size = 6;
 274                 p_data = p_pes->p_first;
 275                 p_byte = p_data->p_payload_start;
 276                 /* Cannot fail because the previous one succeeded. */
 277                 MoveChunk( NULL, &p_data, &p_byte, 6 );
 278
 279                 while( *p_byte == 0xFF && i_pes_header_size < 23 )
 280                 {
 281                     i_pes_header_size++;
 282                     if( MoveChunk( NULL, &p_data, &p_byte, 1 ) != 1 )
 283                     {
 284                         msg_Warn( p_input,
 285                             "PES packet too short to have a MPEG-1 header" );
 286                         input_DeletePES( p_input->p_method_data, p_pes );
 287                         p_pes = NULL;
 288                         return;
 289                     }
 290                 }
 291                 if( i_pes_header_size == 23 )
 292                 {
 293                     msg_Err( p_input, "too much MPEG-1 stuffing" );
 294                     input_DeletePES( p_input->p_method_data, p_pes );
 295                     p_pes = NULL;
 296                     return;
 297                 }
 298
 299                 if( (*p_byte & 0xC0) == 0x40 )
 300                 {
 301                     /* Don't ask why... --Meuuh */
 302                     /* Erm... why ? --Sam */
 303                     /* Well... According to the recommendation, it is for
 304                      * STD_buffer_scale and STD_buffer_size. --Meuuh */
 305                     i_pes_header_size += 2;
 306                     if( MoveChunk( NULL, &p_data, &p_byte, 2 ) != 2 )
 307                     {
 308                         msg_Warn( p_input,
 309                             "PES packet too short to have a MPEG-1 header" );
 310                         input_DeletePES( p_input->p_method_data, p_pes );
 311                         p_pes = NULL;
 312                         return;
 313                     }
 314                 }
 315
 316                 i_pes_header_size++;
 317
 318                 b_has_pts = *p_byte & 0x20;
 319                 b_has_dts = *p_byte & 0x10;
 320
 321                 if( b_has_pts )
 322                 {
 323                     byte_t      p_ts[5];
 324
 325                     i_pes_header_size += 4;
 326                     if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
 327                     {
 328                         msg_Warn( p_input,
 329                             "PES packet too short to have a MPEG-1 header" );
 330                         input_DeletePES( p_input->p_method_data, p_pes );
 331                         p_pes = NULL;
 332                         return;
 333                     }
 334
 335                     p_pes->i_pts = input_ClockGetTS( p_input, p_es->p_pgrm,
 336                        ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
 337                          (((mtime_t)U32_AT(p_ts) & 0xFFFE00) << 6) |
 338                          ((mtime_t)p_ts[3] << 7) |
 339                          ((mtime_t)p_ts[4] >> 1) ) );
 340
 341                     if( b_has_dts )
 342                     {
 343                         i_pes_header_size += 5;
 344                         if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
 345                         {
 346                             msg_Warn( p_input,
 347                               "PES packet too short to have a MPEG-1 header" );
 348                             input_DeletePES( p_input->p_method_data, p_pes );
 349                             p_pes = NULL;
 350                             return;
 351                         }
 352
 353                         p_pes->i_dts = input_ClockGetTS( p_input,
 354                                                          p_es->p_pgrm,
 355                             ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
 356                               (((mtime_t)U32_AT(p_ts) & 0xFFFE00) << 6) |
 357                               ((mtime_t)p_ts[3] << 7) |
 358                               ((mtime_t)p_ts[4] >> 1) ) );
 359                     }
 360                 }
 361             }
 362
 363             break;
 364         }
 365
 366         /* Welcome to the kludge area ! --Meuuh */
 367         if ( p_es->i_fourcc == VLC_FOURCC('a','5','2','b') )
 368         {
 369             /* With A/52 audio, we need to skip the first 4 bytes */
 370             i_pes_header_size += 4;
 371         }
 372
 373         if ( p_es->i_fourcc == VLC_FOURCC('l','p','c','b')
 374               || p_es->i_fourcc == VLC_FOURCC('s','p','u','b')
 375               || p_es->i_fourcc == VLC_FOURCC('d','t','s','b')
 376               || p_es->i_fourcc == VLC_FOURCC('s','d','d','b') )
 377         {
 378             /* stream_private_id */
 379             i_pes_header_size += 1;
 380         }
 381
 382         /* Now we've parsed the header, we just have to indicate in some
 383          * specific data packets where the PES payload begins (renumber
 384          * p_payload_start), so that the decoders can find the beginning
 385          * of their data right out of the box. */
 386         p_data = p_pes->p_first;
 387         i_payload_size = p_data->p_payload_end
 388                                  - p_data->p_payload_start;
 389         while( i_pes_header_size > i_payload_size )
 390         {
 391             /* These packets are entirely filled by the PES header. */
 392             i_pes_header_size -= i_payload_size;
 393             p_data->p_payload_start = p_data->p_payload_end;
 394             /* Go to the next data packet. */
 395             if( (p_data = p_data->p_next) == NULL )
 396             {
 397                 msg_Err( p_input, "PES header bigger than payload" );
 398                 input_DeletePES( p_input->p_method_data, p_pes );
 399                 p_pes = NULL;
 400                 return;
 401             }
 402             i_payload_size = p_data->p_payload_end
 403                                  - p_data->p_payload_start;
 404         }
 405         /* This last packet is partly header, partly payload. */
 406         if( i_payload_size < i_pes_header_size )
 407         {
 408             msg_Err( p_input, "PES header bigger than payload" );
 409             input_DeletePES( p_input->p_method_data, p_pes );
 410             p_pes = NULL;
 411             return;
 412         }
 413         p_data->p_payload_start += i_pes_header_size;
 414
 415
 416         /* Now we can eventually put the PES packet in the decoder's
 417          * PES fifo */
 418         if( p_es->p_decoder_fifo != NULL )
 419         {
 420             input_DecodePES( p_es->p_decoder_fifo, p_pes );
 421         }
 422         else
 423         {
 424             msg_Err( p_input, "no fifo to receive PES %p "
 425                               "(who wrote this damn code ?)", p_pes );
 426             input_DeletePES( p_input->p_method_data, p_pes );
 427         }
 428         p_pes = NULL;
 429     }
 430 #undef p_pes
 431
 432 }
 433
 434 /*****************************************************************************
 435  * GatherPES:
 436  *****************************************************************************
 437  * Gather a PES packet.
 438  *****************************************************************************/
 439 static void GatherPES( input_thread_t * p_input, data_packet_t * p_data,
 440                        es_descriptor_t * p_es,
 441                        vlc_bool_t b_unit_start, vlc_bool_t b_packet_lost )
 442 {
 443 #define p_pes (p_es->p_pes)
 444
 445     /* If we lost data, insert a NULL data packet (philosophy : 0 is quite
 446      * often an escape sequence in decoders, so that should make them wait
 447      * for the next start code). */
 448     if( b_packet_lost )
 449     {
 450         input_NullPacket( p_input, p_es );
 451     }
 452
 453     if( b_unit_start && p_pes != NULL )
 454     {
 455         /* If the data packet contains the begining of a new PES packet, and
 456          * if we were reassembling a PES packet, then the PES should be
 457          * complete now, so parse its header and give it to the decoders. */
 458         ParsePES( p_input, p_es );
 459     }
 460
 461     if( !b_unit_start && p_pes == NULL )
 462     {
 463         /* Random access... */
 464         input_DeletePacket( p_input->p_method_data, p_data );
 465     }
 466     else
 467     {
 468         if( b_unit_start )
 469         {
 470             /* If we are at the beginning of a new PES packet, we must fetch
 471              * a new PES buffer to begin with the reassembly of this PES
 472              * packet. This is also here that we can synchronize with the
 473              * stream if we lost packets or if the decoder has just
 474              * started. */
 475             if( (p_pes = input_NewPES( p_input->p_method_data ) ) == NULL )
 476             {
 477                 msg_Err( p_input, "out of memory" );
 478                 p_input->b_error = 1;
 479                 return;
 480             }
 481             p_pes->i_rate = p_input->stream.control.i_rate;
 482             p_pes->p_first = p_data;
 483
 484             /* If the PES header fits in the first data packet, we can
 485              * already set p_gather->i_pes_real_size. */
 486             if( p_data->p_payload_end - p_data->p_payload_start
 487                     >= PES_HEADER_SIZE )
 488             {
 489                 p_es->i_pes_real_size = ((u16)p_data->p_payload_start[4] << 8)
 490                                          + p_data->p_payload_start[5];
 491                 if ( p_es->i_pes_real_size )
 492                 {
 493                     p_es->i_pes_real_size += 6;
 494                 }
 495             }
 496             else
 497             {
 498                 p_es->i_pes_real_size = 0;
 499             }
 500         }
 501         else
 502         {
 503             /* Update the relations between the data packets */
 504             p_pes->p_last->p_next = p_data;
 505         }
 506
 507         p_pes->p_last = p_data;
 508         p_pes->i_nb_data++;
 509
 510         /* Size of the payload carried in the data packet */
 511         p_pes->i_pes_size += (p_data->p_payload_end
 512                                  - p_data->p_payload_start);
 513
 514         /* We can check if the packet is finished */
 515         if( p_es->i_pes_real_size  && p_pes->i_pes_size >= p_es->i_pes_real_size )
 516         {
 517             if( p_pes->i_pes_size > p_es->i_pes_real_size )
 518             {
 519                 msg_Warn( p_input,
 520                           "Oversized PES packet for PID %d: expected %d, actual %d",
 521                           p_es->i_id, p_es->i_pes_real_size, p_pes->i_pes_size );
 522             }
 523             /* The packet is finished, parse it */
 524             ParsePES( p_input, p_es );
 525         }
 526     }
 527 #undef p_pes
 528 }
 529
 530
 531 /*
 532  * PS Demultiplexing
 533  */
 534
 535 /*****************************************************************************
 536  * GetID: Get the ID of a stream
 537  *****************************************************************************/
 538 static u16 GetID( data_packet_t * p_data )
 539 {
 540     u16         i_id;
 541
 542     i_id = p_data->p_demux_start[3];                            /* stream_id */
 543     if( i_id == 0xBD )
 544     {
 545         /* FIXME : this is not valid if the header is split in multiple
 546          * packets */
 547         /* stream_private_id */
 548         i_id |= p_data->p_demux_start[ 9 + p_data->p_demux_start[8] ] << 8;
 549     }
 550     return( i_id );
 551 }
 552
 553 /*****************************************************************************
 554  * DecodePSM: Decode the Program Stream Map information
 555  *****************************************************************************
 556  * FIXME : loads are not aligned in this function
 557  *****************************************************************************/
 558 static void DecodePSM( input_thread_t * p_input, data_packet_t * p_data )
 559 {
 560     stream_ps_data_t *  p_demux =
 561                  (stream_ps_data_t *)p_input->stream.p_demux_data;
 562     byte_t *            p_byte;
 563     byte_t *            p_end;
 564     unsigned int        i;
 565     unsigned int        i_new_es_number = 0;
 566
 567     if( p_data->p_demux_start + 10 > p_data->p_payload_end )
 568     {
 569         msg_Err( p_input, "PSM too short, packet corrupt" );
 570         return;
 571     }
 572
 573     if( p_demux->b_has_PSM
 574         && p_demux->i_PSM_version == (p_data->p_demux_start[6] & 0x1F) )
 575     {
 576         /* Already got that one. */
 577         return;
 578     }
 579
 580     p_demux->b_has_PSM = 1;
 581     p_demux->i_PSM_version = p_data->p_demux_start[6] & 0x1F;
 582
 583     /* Go to elementary_stream_map_length, jumping over
 584      * program_stream_info. */
 585     p_byte = p_data->p_demux_start + 10
 586               + U16_AT(&p_data->p_demux_start[8]);
 587     if( p_byte > p_data->p_payload_end )
 588     {
 589         msg_Err( p_input, "PSM too short, packet corrupt" );
 590         return;
 591     }
 592     /* This is the full size of the elementary_stream_map.
 593      * 2 == elementary_stream_map_length
 594      * Please note that CRC_32 is not included in the length. */
 595     p_end = p_byte + 2 + U16_AT(p_byte);
 596     p_byte += 2;
 597     if( p_end > p_data->p_payload_end )
 598     {
 599         msg_Err( p_input, "PSM too short, packet corrupt" );
 600         return;
 601     }
 602
 603     vlc_mutex_lock( &p_input->stream.stream_lock );
 604
 605     /* 4 == minimum useful size of a section */
 606     while( p_byte + 4 <= p_end )
 607     {
 608         es_descriptor_t *   p_es = NULL;
 609         uint8_t             i_stream_id = p_byte[1];
 610         /* FIXME: there will be a problem with private streams... (same
 611          * stream_id) */
 612
 613         /* Look for the ES in the ES table */
 614         for( i = i_new_es_number;
 615              i < p_input->stream.pp_programs[0]->i_es_number;
 616              i++ )
 617         {
 618             if( p_input->stream.pp_programs[0]->pp_es[i]->i_stream_id
 619                     == i_stream_id )
 620             {
 621                 p_es = p_input->stream.pp_programs[0]->pp_es[i];
 622                 /* FIXME: do something below */
 623 #if 0
 624                 if( p_es->i_type != p_byte[0] )
 625                 {
 626                     input_DelES( p_input, p_es );
 627                     p_es = NULL;
 628                 }
 629                 else
 630 #endif
 631                 {
 632                     /* Move the ES to the beginning. */
 633                     p_input->stream.pp_programs[0]->pp_es[i]
 634                         = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 635                     p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ]
 636                         = p_es;
 637                     i_new_es_number++;
 638                 }
 639                 break;
 640             }
 641         }
 642
 643         /* The goal is to have all the ES we have just read in the
 644          * beginning of the pp_es table, and all the others at the end,
 645          * so that we can close them more easily at the end. */
 646         if( p_es == NULL )
 647         {
 648             int i_fourcc, i_cat;
 649
 650             switch( p_byte[0] )
 651             {
 652             case MPEG1_VIDEO_ES:
 653             case MPEG2_VIDEO_ES:
 654             case MPEG2_MOTO_VIDEO_ES:
 655                 i_fourcc = VLC_FOURCC('m','p','g','v');
 656                 i_cat = VIDEO_ES;
 657                 break;
 658             case DVD_SPU_ES:
 659                 i_fourcc = VLC_FOURCC('s','p','u','b');
 660                 i_cat = SPU_ES;
 661                 break;
 662             case MPEG1_AUDIO_ES:
 663             case MPEG2_AUDIO_ES:
 664                 i_fourcc = VLC_FOURCC('m','p','g','a');
 665                 i_cat = AUDIO_ES;
 666                 break;
 667             case A52_AUDIO_ES:
 668             case A52DVB_AUDIO_ES:
 669                 i_fourcc = VLC_FOURCC('a','5','2','b');
 670                 i_cat = AUDIO_ES;
 671                 break;
 672             case LPCM_AUDIO_ES:
 673                 i_fourcc = VLC_FOURCC('l','p','c','b');
 674                 i_cat = AUDIO_ES;
 675                 break;
 676             default:
 677                 i_cat = UNKNOWN_ES;
 678                 i_fourcc = 0;
 679                 break;
 680             }
 681
 682             p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 683                                 i_stream_id, i_cat, NULL, 0 );
 684             p_es->i_fourcc = i_fourcc;
 685
 686             /* input_AddES has inserted the new element at the end. */
 687             p_input->stream.pp_programs[0]->pp_es[
 688                 p_input->stream.pp_programs[0]->i_es_number ]
 689                 = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 690             p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ] = p_es;
 691             i_new_es_number++;
 692         }
 693         p_byte += 4 + U16_AT(&p_byte[2]);
 694     }
 695
 696     /* Un-select the streams that are no longer parts of the program. */
 697     while( i_new_es_number < p_input->stream.pp_programs[0]->i_es_number )
 698     {
 699         /* We remove pp_es[i_new_es_member] and not pp_es[i] because the
 700          * list will be emptied starting from the end */
 701         input_DelES( p_input,
 702                      p_input->stream.pp_programs[0]->pp_es[i_new_es_number] );
 703     }
 704
 705     msg_Dbg( p_input, "the stream map after the PSM is now:" );
 706     input_DumpStream( p_input );
 707
 708     vlc_mutex_unlock( &p_input->stream.stream_lock );
 709 }
 710
 711 /*****************************************************************************
 712  * ReadPS: store a PS packet into a data_buffer_t
 713  *****************************************************************************/
 714 #define PEEK( SIZE )                                                        \
 715     i_error = input_Peek( p_input, &p_peek, SIZE );                         \
 716     if( i_error == -1 )                                                     \
 717     {                                                                       \
 718         return( -1 );                                                       \
 719     }                                                                       \
 720     else if( (size_t)i_error < SIZE )                                       \
 721     {                                                                       \
 722         /* EOF */                                                           \
 723         return( 0 );                                                        \
 724     }
 725
 726 static ssize_t ReadPS( input_thread_t * p_input, data_packet_t ** pp_data )
 727 {
 728     byte_t *            p_peek;
 729     size_t              i_packet_size;
 730     ssize_t             i_error, i_read;
 731
 732     /* Read what we believe to be a packet header. */
 733     PEEK( 4 );
 734
 735     if( p_peek[0] || p_peek[1] || p_peek[2] != 1 || p_peek[3] < 0xB9 )
 736     {
 737         if( p_peek[0] || p_peek[1] || p_peek[2] )
 738         {
 739             /* It is common for MPEG-1 streams to pad with zeros
 740              * (although it is forbidden by the recommendation), so
 741              * don't bother everybody in this case. */
 742             msg_Warn( p_input, "garbage (0x%.2x%.2x%.2x%.2x)",
 743                       p_peek[0], p_peek[1], p_peek[2], p_peek[3] );
 744         }
 745
 746         /* This is not the startcode of a packet. Read the stream
 747          * until we find one. */
 748         while( p_peek[0] || p_peek[1] || p_peek[2] != 1 || p_peek[3] < 0xB9 )
 749         {
 750             p_input->p_current_data++;
 751             PEEK( 4 );
 752             if( p_input->b_die ) return( -1 );
 753         }
 754         /* Packet found. */
 755     }
 756
 757     /* 0x1B9 == SYSTEM_END_CODE, it is only 4 bytes long. */
 758     if( p_peek[3] != 0xB9 )
 759     {
 760         /* The packet is at least 6 bytes long. */
 761         PEEK( 6 );
 762
 763         if( p_peek[3] != 0xBA )
 764         {
 765             /* That's the case for all packets, except pack header. */
 766             i_packet_size = (p_peek[4] << 8) | p_peek[5];
 767         }
 768         else
 769         {
 770             /* Pack header. */
 771             if( (p_peek[4] & 0xC0) == 0x40 )
 772             {
 773                 /* MPEG-2 */
 774                 i_packet_size = 8;
 775             }
 776             else if( (p_peek[4] & 0xF0) == 0x20 )
 777             {
 778                 /* MPEG-1 */
 779                 i_packet_size = 6;
 780             }
 781             else
 782             {
 783                 msg_Err( p_input, "unable to determine stream type" );
 784                 return( -1 );
 785             }
 786         }
 787     }
 788     else
 789     {
 790         /* System End Code */
 791         i_packet_size = -2;
 792     }
 793
 794     /* Fetch a packet of the appropriate size. */
 795     i_read = input_SplitBuffer( p_input, pp_data, i_packet_size + 6 );
 796     if( i_read <= 0 )
 797     {
 798         return( i_read );
 799     }
 800
 801     /* In MPEG-2 pack headers we still have to read stuffing bytes. */
 802     if( ((*pp_data)->p_demux_start[3] == 0xBA) && (i_packet_size == 8) )
 803     {
 804         size_t i_stuffing = ((*pp_data)->p_demux_start[13] & 0x7);
 805         /* Force refill of the input buffer - though we don't care
 806          * about p_peek. Please note that this is unoptimized. */
 807         PEEK( i_stuffing );
 808         p_input->p_current_data += i_stuffing;
 809     }
 810
 811     return( 1 );
 812 }
 813
 814 #undef PEEK
 815
 816 /*****************************************************************************
 817  * ParsePS: read the PS header
 818  *****************************************************************************/
 819 static es_descriptor_t * ParsePS( input_thread_t * p_input,
 820                                   data_packet_t * p_data )
 821 {
 822     uint32_t            i_code;
 823     es_descriptor_t *   p_es = NULL;
 824
 825     i_code = p_data->p_demux_start[3];
 826
 827     if( i_code > 0xBC ) /* ES start code */
 828     {
 829         uint16_t            i_id;
 830         unsigned int        i_dummy;
 831
 832         /* This is a PES packet. Find out if we want it or not. */
 833         i_id = GetID( p_data );
 834
 835         vlc_mutex_lock( &p_input->stream.stream_lock );
 836         if( p_input->stream.pp_programs[0]->b_is_ok )
 837         {
 838             /* Look only at the selected ES. */
 839             for( i_dummy = 0; i_dummy < p_input->stream.i_selected_es_number;
 840                  i_dummy++ )
 841             {
 842                 if( p_input->stream.pp_selected_es[i_dummy] != NULL
 843                     && p_input->stream.pp_selected_es[i_dummy]->i_id == i_id )
 844                 {
 845                     p_es = p_input->stream.pp_selected_es[i_dummy];
 846                     break;
 847                 }
 848             }
 849         }
 850         else
 851         {
 852             vlc_bool_t b_auto_spawn = VLC_FALSE;
 853             stream_ps_data_t * p_demux =
 854               (stream_ps_data_t *)p_input->stream.pp_programs[0]->p_demux_data;
 855
 856             /* Search all ES ; if not found -> AddES */
 857             p_es = input_FindES( p_input, i_id );
 858
 859             if( p_es == NULL && !p_demux->b_has_PSM )
 860             {
 861                 int i_fourcc, i_cat;
 862
 863                 /* Set stream type and auto-spawn. */
 864                 if( (i_id & 0xF0) == 0xE0 )
 865                 {
 866                     /* MPEG video */
 867                     i_fourcc = VLC_FOURCC('m','p','g','v');
 868                     i_cat = VIDEO_ES;
 869 #ifdef AUTO_SPAWN
 870                     if( !p_input->stream.b_seekable ) b_auto_spawn = VLC_TRUE;
 871 #endif
 872                 }
 873                 else if( (i_id & 0xE0) == 0xC0 )
 874                 {
 875                     /* MPEG audio */
 876                     i_fourcc = VLC_FOURCC('m','p','g','a');
 877                     i_cat = AUDIO_ES;
 878 #ifdef AUTO_SPAWN
 879                     if( !p_input->stream.b_seekable )
 880                     if( config_GetInt( p_input, "audio-channel" )
 881                             == (i_id & 0x1F) ||
 882                         ( config_GetInt( p_input, "audio-channel" ) < 0
 883                           && !(i_id & 0x1F) ) )
 884                     switch( config_GetInt( p_input, "audio-type" ) )
 885                     {
 886                     case -1:
 887                     case REQUESTED_MPEG:
 888                         b_auto_spawn = VLC_TRUE;
 889                     }
 890 #endif
 891                 }
 892                 else if( (i_id & 0xF8FF) == 0x88BD )
 893                 {
 894                     i_fourcc = VLC_FOURCC('d','t','s','b');
 895                     i_cat = AUDIO_ES;
 896 #ifdef AUTO_SPAWN
 897                     if( !p_input->stream.b_seekable )
 898                     if( config_GetInt( p_input, "audio-channel" )
 899                             == ((i_id & 0x700) >> 8) ||
 900                         ( config_GetInt( p_input, "audio-channel" ) < 0
 901                           && !((i_id & 0x700) >> 8)) )
 902                     switch( config_GetInt( p_input, "audio-type" ) )
 903                     {
 904                     case -1:
 905                     case REQUESTED_DTS:
 906                         b_auto_spawn = VLC_TRUE;
 907                     }
 908 #endif
 909                 }
 910                 else if( (i_id & 0xF0FF) == 0x80BD )
 911                 {
 912                     /* A52 audio (0x80->0x8F) */
 913                     i_fourcc = VLC_FOURCC('a','5','2','b');
 914                     i_cat = AUDIO_ES;
 915 #ifdef AUTO_SPAWN
 916                     if( !p_input->stream.b_seekable )
 917                     if( config_GetInt( p_input, "audio-channel" )
 918                             == ((i_id & 0xF00) >> 8) ||
 919                         ( config_GetInt( p_input, "audio-channel" ) < 0
 920                           && !((i_id & 0xF00) >> 8)) )
 921                     switch( config_GetInt( p_input, "audio-type" ) )
 922                     {
 923                     case -1:
 924                     case REQUESTED_A52:
 925                         b_auto_spawn = VLC_TRUE;
 926                     }
 927 #endif
 928                 }
 929                 else if( (i_id & 0xE0FF) == 0x20BD )
 930                 {
 931                     /* Subtitles video (0x20->0x3F) */
 932                     i_fourcc = VLC_FOURCC('s','p','u','b');
 933                     i_cat = SPU_ES;
 934 #ifdef AUTO_SPAWN
 935                     if( !p_input->stream.b_seekable )
 936                     if( config_GetInt( p_input, "spu-channel" )
 937                            == ((i_id & 0x1F00) >> 8) )
 938                     {
 939                         b_auto_spawn = VLC_TRUE;
 940                     }
 941 #endif
 942                 }
 943                 else if( (i_id & 0xF0FF) == 0xA0BD )
 944                 {
 945                     /* LPCM audio (0xA0->0xAF) */
 946                     i_fourcc = VLC_FOURCC('l','p','c','b');
 947                     i_cat = AUDIO_ES;
 948                 }
 949                 else
 950                 {
 951                     i_cat = UNKNOWN_ES;
 952                     i_fourcc = 0;
 953                 }
 954
 955                 p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 956                                     i_id, i_cat, NULL, 0 );
 957
 958                 p_es->i_stream_id = p_data->p_demux_start[3];
 959                 p_es->i_fourcc = i_fourcc;
 960
 961                 if( b_auto_spawn ) input_SelectES( p_input, p_es );
 962
 963                 /* Tell the interface the stream has changed */
 964                 p_input->stream.b_changed = 1;
 965             }
 966         } /* stream.b_is_ok */
 967         vlc_mutex_unlock( &p_input->stream.stream_lock );
 968     } /* i_code > 0xBC */
 969
 970     return( p_es );
 971 }
 972
 973 /*****************************************************************************
 974  * DemuxPS: first step of demultiplexing: the PS header
 975  *****************************************************************************/
 976 static void DemuxPS( input_thread_t * p_input, data_packet_t * p_data )
 977 {
 978     u32                 i_code;
 979     vlc_bool_t          b_trash = 0;
 980     es_descriptor_t *   p_es = NULL;
 981
 982     i_code = ((u32)p_data->p_demux_start[0] << 24)
 983                 | ((u32)p_data->p_demux_start[1] << 16)
 984                 | ((u32)p_data->p_demux_start[2] << 8)
 985                 | p_data->p_demux_start[3];
 986     if( i_code <= 0x1BC )
 987     {
 988         switch( i_code )
 989         {
 990         case 0x1BA: /* PACK_START_CODE */
 991             {
 992                 /* Read the SCR. */
 993                 mtime_t         scr_time;
 994                 u32             i_mux_rate;
 995
 996                 if( (p_data->p_demux_start[4] & 0xC0) == 0x40 )
 997                 {
 998                     /* MPEG-2 */
 999                     byte_t      p_header[14];
1000                     byte_t *    p_byte;
1001                     p_byte = p_data->p_demux_start;
1002
1003                     if( MoveChunk( p_header, &p_data, &p_byte, 14 ) != 14 )
1004                     {
1005                         msg_Warn( p_input,
1006                                   "packet too short to have a header" );
1007                         b_trash = 1;
1008                         break;
1009                     }
1010                     scr_time =
1011                          ((mtime_t)(p_header[4] & 0x38) << 27) |
1012                          ((mtime_t)(U32_AT(p_header + 4) & 0x03FFF800)
1013                                         << 4) |
1014                          ((( ((mtime_t)U16_AT(p_header + 6) << 16)
1015                             | (mtime_t)U16_AT(p_header + 8) ) & 0x03FFF800)
1016                                         >> 11);
1017
1018                     /* mux_rate */
1019                     i_mux_rate = ((u32)U16_AT(p_header + 10) << 6)
1020                                    | (p_header[12] >> 2);
1021                     /* FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
1022                      * This is the biggest kludge ever !
1023                      * I don't know what's wrong with mux_rate calculation
1024                      * but this heuristic works well : */
1025                     i_mux_rate <<= 1;
1026                     i_mux_rate /= 3;
1027                 }
1028                 else
1029                 {
1030                     /* MPEG-1 SCR is like PTS. */
1031                     byte_t      p_header[12];
1032                     byte_t *    p_byte;
1033                     p_byte = p_data->p_demux_start;
1034
1035                     if( MoveChunk( p_header, &p_data, &p_byte, 12 ) != 12 )
1036                     {
1037                         msg_Warn( p_input,
1038                                   "packet too short to have a header" );
1039                         b_trash = 1;
1040                         break;
1041                     }
1042                     scr_time =
1043                          ((mtime_t)(p_header[4] & 0x0E) << 29) |
1044                          (((mtime_t)U32_AT(p_header + 4) & 0xFFFE00) << 6) |
1045                          ((mtime_t)p_header[7] << 7) |
1046                          ((mtime_t)p_header[8] >> 1);
1047
1048                     /* mux_rate */
1049                     i_mux_rate = (U32_AT(p_header + 8) & 0x7FFFFE) >> 1;
1050                 }
1051                 /* Call the pace control. */
1052                 input_ClockManageRef( p_input,
1053                                       p_input->stream.p_selected_program,
1054                                       scr_time );
1055
1056                 if( i_mux_rate != p_input->stream.i_mux_rate
1057                      && p_input->stream.i_mux_rate )
1058                 {
1059                     msg_Warn( p_input,
1060                               "mux_rate changed, expect cosmetic errors" );
1061                 }
1062                 p_input->stream.i_mux_rate = i_mux_rate;
1063
1064                 b_trash = 1;
1065             }
1066             break;
1067
1068         case 0x1BB: /* SYSTEM_START_CODE */
1069             b_trash = 1;                              /* Nothing interesting */
1070             break;
1071
1072         case 0x1BC: /* PROGRAM_STREAM_MAP_CODE */
1073             DecodePSM( p_input, p_data );
1074             b_trash = 1;
1075             break;
1076
1077         case 0x1B9: /* PROGRAM_END_CODE */
1078             b_trash = 1;
1079             break;
1080
1081         default:
1082             /* This should not happen */
1083             b_trash = 1;
1084             msg_Warn( p_input, "unwanted packet received "
1085                                "with startcode 0x%.8x", i_code );
1086         }
1087     }
1088     else
1089     {
1090         p_es = ParsePS( p_input, p_data );
1091
1092         vlc_mutex_lock( &p_input->stream.control.control_lock );
1093         if( p_es != NULL && p_es->p_decoder_fifo != NULL
1094              && (p_es->i_cat != AUDIO_ES || !p_input->stream.control.b_mute) )
1095         {
1096             vlc_mutex_unlock( &p_input->stream.control.control_lock );
1097             p_es->c_packets++;
1098             GatherPES( p_input, p_data, p_es, 1, 0 );
1099         }
1100         else
1101         {
1102             vlc_mutex_unlock( &p_input->stream.control.control_lock );
1103             b_trash = 1;
1104         }
1105     }
1106
1107     /* Trash the packet if it has no payload or if it isn't selected */
1108     if( b_trash )
1109     {
1110         input_DeletePacket( p_input->p_method_data, p_data );
1111         p_input->stream.c_packets_trashed++;
1112     }
1113 }
1114
1115
1116 /*
1117  * TS Demultiplexing
1118  */
1119
1120 /*****************************************************************************
1121  * ReadTS: store a TS packet into a data_buffer_t
1122  *****************************************************************************/
1123 #define PEEK( SIZE )                                                        \
1124     i_error = input_Peek( p_input, &p_peek, SIZE );                         \
1125     if( i_error == -1 )                                                     \
1126     {                                                                       \
1127         return( -1 );                                                       \
1128     }                                                                       \
1129     else if( i_error < SIZE )                                               \
1130     {                                                                       \
1131         /* EOF */                                                           \
1132         return( 0 );                                                        \
1133     }
1134
1135 static ssize_t ReadTS( input_thread_t * p_input, data_packet_t ** pp_data )
1136 {
1137     byte_t *            p_peek;
1138     ssize_t             i_error, i_read;
1139
1140     PEEK( 1 );
1141
1142     if( *p_peek != TS_SYNC_CODE )
1143     {
1144         msg_Warn( p_input, "garbage at input (%x)", *p_peek );
1145
1146         if( p_input->i_mtu )
1147         {
1148             while( *p_peek != TS_SYNC_CODE )
1149             {
1150                 /* Try to resync on next packet. */
1151                 PEEK( TS_PACKET_SIZE );
1152                 p_input->p_current_data += TS_PACKET_SIZE;
1153                 PEEK( 1 );
1154             }
1155         }
1156         else
1157         {
1158             /* Move forward until we find 0x47 (and hope it's the good
1159              * one... FIXME) */
1160             while( *p_peek != TS_SYNC_CODE )
1161             {
1162                 p_input->p_current_data++;
1163                 PEEK( 1 );
1164             }
1165         }
1166     }
1167
1168     i_read = input_SplitBuffer( p_input, pp_data, TS_PACKET_SIZE );
1169     if( i_read <= 0 )
1170     {
1171         return( i_read );
1172     }
1173
1174     return( 1 );
1175 }
1176
1177 /*****************************************************************************
1178  * DemuxTS: first step of demultiplexing: the TS header
1179  *****************************************************************************/
1180 static void DemuxTS( input_thread_t * p_input, data_packet_t * p_data,
1181                      psi_callback_t pf_psi_callback )
1182 {
1183     uint16_t            i_pid;
1184     unsigned int        i_dummy;
1185     vlc_bool_t          b_adaptation;         /* Adaptation field is present */
1186     vlc_bool_t          b_payload;                 /* Packet carries payload */
1187     vlc_bool_t          b_unit_start;  /* A PSI or a PES start in the packet */
1188     vlc_bool_t          b_trash = 0;             /* Is the packet unuseful ? */
1189     vlc_bool_t          b_lost = 0;             /* Was there a packet loss ? */
1190     vlc_bool_t          b_psi = 0;                        /* Is this a PSI ? */
1191     vlc_bool_t          b_pcr = 0;                   /* Does it have a PCR ? */
1192     es_descriptor_t *   p_es = NULL;
1193     es_ts_data_t *      p_es_demux = NULL;
1194     pgrm_ts_data_t *    p_pgrm_demux = NULL;
1195     stream_ts_data_t *  p_stream_demux =
1196                           (stream_ts_data_t *)p_input->stream.p_demux_data;
1197
1198 #define p (p_data->p_demux_start)
1199     /* Extract flags values from TS common header. */
1200     i_pid = ((p[1] & 0x1F) << 8) | p[2];
1201     b_unit_start = (p[1] & 0x40);
1202     b_adaptation = (p[3] & 0x20);
1203     b_payload = (p[3] & 0x10);
1204
1205     /* Was there a transport error ? */
1206     if ( p[1] & 0x80 )
1207     {
1208         msg_Warn( p_input, "transport_error_indicator set for PID %d counter %x", i_pid, p[3] & 0x0f );
1209     }
1210
1211     /* Find out the elementary stream. */
1212     vlc_mutex_lock( &p_input->stream.stream_lock );
1213
1214     for( i_dummy = 0; i_dummy < p_input->stream.i_pgrm_number; i_dummy ++ )
1215     {
1216         if( (( pgrm_ts_data_t * ) p_input->stream.pp_programs[i_dummy]->
1217                     p_demux_data)->i_pcr_pid == i_pid )
1218         {
1219             b_pcr = 1;
1220             break;
1221         }
1222     }
1223
1224     p_es = input_FindES( p_input, i_pid );
1225
1226     if( (p_es != NULL) && (p_es->p_demux_data != NULL) )
1227     {
1228         p_es_demux = (es_ts_data_t *)p_es->p_demux_data;
1229
1230         if( p_es_demux->b_psi )
1231         {
1232             b_psi = 1;
1233         }
1234         else
1235         {
1236             p_pgrm_demux = (pgrm_ts_data_t *)p_es->p_pgrm->p_demux_data;
1237         }
1238     }
1239
1240     vlc_mutex_lock( &p_input->stream.control.control_lock );
1241     if( ( p_es == NULL ) || (p_es->i_cat == AUDIO_ES
1242                               && p_input->stream.control.b_mute) )
1243     {
1244         /* Not selected. Just read the adaptation field for a PCR. */
1245         b_trash = 1;
1246     }
1247     else if( p_es->p_decoder_fifo == NULL && !b_psi )
1248     {
1249         b_trash = 1;
1250     }
1251
1252     vlc_mutex_unlock( &p_input->stream.control.control_lock );
1253     vlc_mutex_unlock( &p_input->stream.stream_lock );
1254
1255
1256     /* Don't change the order of the tests : if b_psi then p_pgrm_demux
1257      * may still be null. Who said it was ugly ?
1258      * I have written worse. --Meuuh */
1259     if( ( p_es ) &&
1260         ((p_es->p_decoder_fifo != NULL) || b_psi || b_pcr ) )
1261     {
1262         p_es->c_packets++;
1263
1264         /* Extract adaptation field information if any */
1265
1266         if( !b_adaptation )
1267         {
1268             /* We don't have any adaptation_field, so payload starts
1269              * immediately after the 4 byte TS header */
1270             p_data->p_payload_start += 4;
1271         }
1272         else
1273         {
1274             /* p[4] is adaptation_field_length minus one */
1275             p_data->p_payload_start += 5 + p[4];
1276
1277             /* The adaptation field can be limited to the
1278              * adaptation_field_length byte, so that there is nothing to do:
1279              * skip this possibility */
1280             if( p[4] )
1281             {
1282                 /* If the packet has both adaptation_field and payload,
1283                  * adaptation_field cannot be more than 182 bytes long; if
1284                  * there is only an adaptation_field, it must fill the next
1285                  * 183 bytes. */
1286                 if( b_payload ? (p[4] > 182) : (p[4] != 183) )
1287                 {
1288                     msg_Warn( p_input, "invalid TS adaptation field for PID %d (%2x)",
1289                               i_pid, p[4] );
1290                     p_data->b_discard_payload = 1;
1291                     p_es->c_invalid_packets++;
1292
1293                     /* The length was invalid so we shouldn't have added it to
1294                      * p_payload_start above.  Ensure p_payload_start has a
1295                      * valid value by setting it equal to p_payload_end.  This
1296                      * also stops any data being processed from the packet.
1297                      */
1298                     p_data->p_payload_start = p_data->p_payload_end;
1299                 }
1300
1301                 /* Now we are sure that the byte containing flags is present:
1302                  * read it */
1303                 else
1304                 {
1305                     /* discontinuity_indicator */
1306                     if( p[5] & 0x80 )
1307                     {
1308                         msg_Warn( p_input,
1309                             "discontinuity_indicator encountered by TS demux "
1310                             "(PID %d: current %d, packet %d)",
1311                             i_pid,
1312                             ( p_es_demux->i_continuity_counter ) & 0x0f,
1313                             p[3] & 0x0f );
1314
1315                         /* If the PID carries the PCR, there will be a system
1316                          * time-based discontinuity. We let the PCR decoder
1317                          * handle that. */
1318                         p_es->p_pgrm->i_synchro_state = SYNCHRO_REINIT;
1319
1320                         /* Don't resynchronise the counter here - it will
1321                          * be checked later and b_lost will then be set if
1322                          * necessary.
1323                          */
1324                     }
1325
1326                 } /* valid TS adaptation field ? */
1327             } /* length > 0 */
1328         } /* has adaptation field */
1329         /* Check the continuity of the stream. */
1330         i_dummy = ((p[3] & 0x0f) - p_es_demux->i_continuity_counter) & 0x0f;
1331         if( b_payload &&
1332                 ( i_dummy == 1 || (b_psi && p_stream_demux->b_buggy_psi ) ) )
1333         {
1334             /* Everything is ok, just increase our counter */
1335             (p_es_demux->i_continuity_counter)++;
1336         }
1337         else
1338         {
1339             if( !b_payload && i_dummy == 0 )
1340             {
1341                 /* This is a packet without payload, this is allowed by the
1342                  * draft. As there is nothing interesting in this packet
1343                  * (except PCR that have already been handled), we can trash
1344                  * the packet. */
1345                 b_trash = 1;
1346             }
1347             else if( !b_payload )
1348             {
1349                 /* If there is no payload, the counter should be unchanged */
1350                 msg_Warn( p_input, "packet rxd for PID %d with no payload but "
1351                         "wrong counter: current %d, packet %d", i_pid,
1352                         p_es_demux->i_continuity_counter & 0x0f, p[3] & 0x0f );
1353             }
1354             else if( i_dummy <= 0 )
1355             {
1356                 /* Duplicate packet: mark it as being to be trashed. */
1357                 msg_Warn( p_input,
1358                           "duplicate packet received for PID %d (counter %d)",
1359                           p_es->i_id, p[3] & 0x0f );
1360                 b_trash = 1;
1361             }
1362             else if( p_es_demux->i_continuity_counter == 0xFF )
1363             {
1364                 /* This means that the packet is the first one we receive for
1365                  * this ES since the continuity counter ranges between 0 and
1366                  * 0x0F excepts when it has been initialized by the input:
1367                  * init the counter to the correct value. */
1368                 msg_Warn( p_input, "first packet for PID %d received "
1369                                    "by TS demux", p_es->i_id );
1370                 p_es_demux->i_continuity_counter = (p[3] & 0x0f);
1371             }
1372             else
1373             {
1374                 /* This can indicate that we missed a packet or that the
1375                  * continuity_counter wrapped and we received a dup packet:
1376                  * as we don't know, do as if we missed a packet to be sure
1377                  * to recover from this situation */
1378                 msg_Warn( p_input,
1379                           "packet lost by TS demux for PID %d: current %d, packet %d",
1380                           i_pid,
1381                           p_es_demux->i_continuity_counter & 0x0f,
1382                           p[3] & 0x0f );
1383                 b_lost = 1;
1384                 p_es_demux->i_continuity_counter = p[3] & 0x0f;
1385             } /* not continuous */
1386         } /* continuity */
1387     } /* if selected or PCR */
1388
1389     /* Handle PCR */
1390     if( b_pcr && b_adaptation && (p[5] & 0x10) && p[4]>=7 )
1391     {
1392         /* Read the PCR. */
1393         mtime_t     pcr_time;
1394         pcr_time = ( (mtime_t)p[6] << 25 ) |
1395                    ( (mtime_t)p[7] << 17 ) |
1396                    ( (mtime_t)p[8] << 9 ) |
1397                    ( (mtime_t)p[9] << 1 ) |
1398                    ( (mtime_t)p[10] >> 7 );
1399         /* Call the pace control. */
1400         for( i_dummy = 0; i_dummy < p_input->stream.i_pgrm_number;
1401                                 i_dummy ++ )
1402         {
1403             if( ( ( pgrm_ts_data_t * ) p_input->stream.pp_programs[i_dummy]->
1404                         p_demux_data )->i_pcr_pid == i_pid )
1405             {
1406                 input_ClockManageRef( p_input,
1407                     p_input->stream.pp_programs[i_dummy], pcr_time );
1408             }
1409         }
1410
1411     }
1412
1413     /* Trash the packet if it has no payload or if it isn't selected */
1414     if( b_trash )
1415     {
1416         input_DeletePacket( p_input->p_method_data, p_data );
1417         p_input->stream.c_packets_trashed++;
1418     }
1419     else
1420     {
1421         if( b_psi )
1422         {
1423             /* The payload contains PSI tables */
1424             (* pf_psi_callback) ( p_input, p_data, p_es, b_unit_start );
1425         }
1426         else
1427         {
1428             /* The payload carries a PES stream */
1429             GatherPES( p_input, p_data, p_es, b_unit_start, b_lost );
1430         }
1431
1432     }
1433
1434 #undef p
1435
1436 }