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 1.6 2002/10/20 12:23:48 massiot 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 #include <sys/types.h>                                              /* off_t */
  34
  35 #include <vlc/vlc.h>
  36 #include <vlc/input.h>
  37
  38 #include "system.h"
  39
  40 /*****************************************************************************
  41  * Local prototypes
  42  *****************************************************************************/
  43 static int Activate ( vlc_object_t * );
  44
  45 static ssize_t           ReadPS  ( input_thread_t *, data_packet_t ** );
  46 static es_descriptor_t * ParsePS ( input_thread_t *, data_packet_t * );
  47 static void              DemuxPS ( input_thread_t *, data_packet_t * );
  48
  49 static ssize_t           ReadTS  ( input_thread_t *, data_packet_t ** );
  50 static void              DemuxTS ( input_thread_t *, data_packet_t *,
  51                                    psi_callback_t );
  52
  53 /*****************************************************************************
  54  * Module descriptor
  55  *****************************************************************************/
  56 vlc_module_begin();
  57     set_description( _("generic ISO 13818-1 MPEG demultiplexing") );
  58     set_capability( "mpeg-system", 100 );
  59     set_callbacks( Activate, NULL );
  60 vlc_module_end();
  61
  62 /*****************************************************************************
  63  * Activate: initializes helper functions
  64  *****************************************************************************/
  65 static int Activate ( vlc_object_t *p_this )
  66 {
  67     static mpeg_demux_t mpeg_demux =
  68                     { NULL, ReadPS, ParsePS, DemuxPS, ReadTS, DemuxTS };
  69
  70     memcpy( p_this->p_private, &mpeg_demux, sizeof( mpeg_demux ) );
  71
  72     return VLC_SUCCESS;
  73 }
  74
  75 /*
  76  * PES Packet management
  77  */
  78
  79 /*****************************************************************************
  80  * MoveChunk
  81  *****************************************************************************
  82  * Small utility function used to parse discontinuous headers safely. Copies
  83  * i_buf_len bytes of data to a buffer and returns the size copied.
  84  * It also solves some alignment problems on non-IA-32, non-PPC processors.
  85  * This is a variation on the theme of input_ext-dec.h:GetChunk().
  86  *****************************************************************************/
  87 static inline size_t MoveChunk( byte_t * p_dest, data_packet_t ** pp_data_src,
  88                                 byte_t ** pp_src, size_t i_buf_len )
  89 {
  90     ptrdiff_t           i_available;
  91
  92     if( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
  93             >= i_buf_len )
  94     {
  95         if( p_dest != NULL )
  96             memcpy( p_dest, *pp_src, i_buf_len );
  97         *pp_src += i_buf_len;
  98         return( i_buf_len );
  99     }
 100     else
 101     {
 102         size_t          i_init_len = i_buf_len;
 103
 104         do
 105         {
 106             if( p_dest != NULL )
 107                 memcpy( p_dest, *pp_src, i_available );
 108             *pp_data_src = (*pp_data_src)->p_next;
 109             i_buf_len -= i_available;
 110             p_dest += i_available;
 111             if( *pp_data_src == NULL )
 112             {
 113                 *pp_src = NULL;
 114                 return( i_init_len - i_buf_len );
 115             }
 116             *pp_src = (*pp_data_src)->p_payload_start;
 117         }
 118         while( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
 119                 <= 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         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_es->i_stream_id )
 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] + 6;
 491             }
 492             else
 493             {
 494                 p_es->i_pes_real_size = 0;
 495             }
 496         }
 497         else
 498         {
 499             /* Update the relations between the data packets */
 500             p_pes->p_last->p_next = p_data;
 501         }
 502
 503         p_pes->p_last = p_data;
 504         p_pes->i_nb_data++;
 505
 506         /* Size of the payload carried in the data packet */
 507         p_pes->i_pes_size += (p_data->p_payload_end
 508                                  - p_data->p_payload_start);
 509
 510         /* We can check if the packet is finished */
 511         if( p_pes->i_pes_size == p_es->i_pes_real_size )
 512         {
 513             /* The packet is finished, parse it */
 514             ParsePES( p_input, p_es );
 515         }
 516     }
 517 #undef p_pes
 518 }
 519
 520
 521 /*
 522  * PS Demultiplexing
 523  */
 524
 525 /*****************************************************************************
 526  * GetID: Get the ID of a stream
 527  *****************************************************************************/
 528 static u16 GetID( data_packet_t * p_data )
 529 {
 530     u16         i_id;
 531
 532     i_id = p_data->p_demux_start[3];                            /* stream_id */
 533     if( i_id == 0xBD )
 534     {
 535         /* FIXME : this is not valid if the header is split in multiple
 536          * packets */
 537         /* stream_private_id */
 538         i_id |= p_data->p_demux_start[ 9 + p_data->p_demux_start[8] ] << 8;
 539     }
 540     return( i_id );
 541 }
 542
 543 /*****************************************************************************
 544  * DecodePSM: Decode the Program Stream Map information
 545  *****************************************************************************
 546  * FIXME : loads are not aligned in this function
 547  *****************************************************************************/
 548 static void DecodePSM( input_thread_t * p_input, data_packet_t * p_data )
 549 {
 550     stream_ps_data_t *  p_demux =
 551                  (stream_ps_data_t *)p_input->stream.p_demux_data;
 552     byte_t *            p_byte;
 553     byte_t *            p_end;
 554     int                 i;
 555     int                 i_new_es_number = 0;
 556
 557     if( p_data->p_demux_start + 10 > p_data->p_payload_end )
 558     {
 559         msg_Err( p_input, "PSM too short, packet corrupt" );
 560         return;
 561     }
 562
 563     if( p_demux->b_has_PSM
 564         && p_demux->i_PSM_version == (p_data->p_demux_start[6] & 0x1F) )
 565     {
 566         /* Already got that one. */
 567         return;
 568     }
 569
 570     p_demux->b_has_PSM = 1;
 571     p_demux->i_PSM_version = p_data->p_demux_start[6] & 0x1F;
 572
 573     /* Go to elementary_stream_map_length, jumping over
 574      * program_stream_info. */
 575     p_byte = p_data->p_demux_start + 10
 576               + U16_AT(&p_data->p_demux_start[8]);
 577     if( p_byte > p_data->p_payload_end )
 578     {
 579         msg_Err( p_input, "PSM too short, packet corrupt" );
 580         return;
 581     }
 582     /* This is the full size of the elementary_stream_map.
 583      * 2 == elementary_stream_map_length
 584      * Please note that CRC_32 is not included in the length. */
 585     p_end = p_byte + 2 + U16_AT(p_byte);
 586     p_byte += 2;
 587     if( p_end > p_data->p_payload_end )
 588     {
 589         msg_Err( p_input, "PSM too short, packet corrupt" );
 590         return;
 591     }
 592
 593     vlc_mutex_lock( &p_input->stream.stream_lock );
 594
 595     /* 4 == minimum useful size of a section */
 596     while( p_byte + 4 <= p_end )
 597     {
 598         es_descriptor_t *   p_es = NULL;
 599         u8                  i_stream_id = p_byte[1];
 600         /* FIXME: there will be a problem with private streams... (same
 601          * stream_id) */
 602
 603         /* Look for the ES in the ES table */
 604         for( i = i_new_es_number;
 605              i < p_input->stream.pp_programs[0]->i_es_number;
 606              i++ )
 607         {
 608             if( p_input->stream.pp_programs[0]->pp_es[i]->i_stream_id
 609                     == i_stream_id )
 610             {
 611                 p_es = p_input->stream.pp_programs[0]->pp_es[i];
 612                 /* FIXME: do something below */
 613 #if 0
 614                 if( p_es->i_type != p_byte[0] )
 615                 {
 616                     input_DelES( p_input, p_es );
 617                     p_es = NULL;
 618                 }
 619                 else
 620 #endif
 621                 {
 622                     /* Move the ES to the beginning. */
 623                     p_input->stream.pp_programs[0]->pp_es[i]
 624                         = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 625                     p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ]
 626                         = p_es;
 627                     i_new_es_number++;
 628                 }
 629                 break;
 630             }
 631         }
 632
 633         /* The goal is to have all the ES we have just read in the
 634          * beginning of the pp_es table, and all the others at the end,
 635          * so that we can close them more easily at the end. */
 636         if( p_es == NULL )
 637         {
 638             p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 639                                 i_stream_id, 0 );
 640             switch( p_byte[0] )
 641             {
 642             case MPEG1_VIDEO_ES:
 643             case MPEG2_VIDEO_ES:
 644                 p_es->i_fourcc = VLC_FOURCC('m','p','g','v');
 645                 p_es->i_cat = VIDEO_ES;
 646                 break;
 647             case DVD_SPU_ES:
 648                 p_es->i_fourcc = VLC_FOURCC('s','p','u','b');
 649                 p_es->i_cat = SPU_ES;
 650                 break;
 651             case MPEG1_AUDIO_ES:
 652             case MPEG2_AUDIO_ES:
 653                 p_es->i_fourcc = VLC_FOURCC('m','p','g','a');
 654                 p_es->i_cat = AUDIO_ES;
 655                 break;
 656             case A52_AUDIO_ES:
 657             case A52DVB_AUDIO_ES:
 658                 p_es->i_fourcc = VLC_FOURCC('a','5','2','b');
 659                 p_es->i_cat = AUDIO_ES;
 660                 break;
 661             case LPCM_AUDIO_ES:
 662                 p_es->i_fourcc = VLC_FOURCC('l','p','c','b');
 663                 p_es->i_cat = AUDIO_ES;
 664                 break;
 665             default:
 666                 p_es->i_fourcc = 0;
 667                 break;
 668             }
 669
 670             /* input_AddES has inserted the new element at the end. */
 671             p_input->stream.pp_programs[0]->pp_es[
 672                 p_input->stream.pp_programs[0]->i_es_number ]
 673                 = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
 674             p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ] = p_es;
 675             i_new_es_number++;
 676         }
 677         p_byte += 4 + U16_AT(&p_byte[2]);
 678     }
 679
 680     /* Un-select the streams that are no longer parts of the program. */
 681     while( i_new_es_number < p_input->stream.pp_programs[0]->i_es_number )
 682     {
 683         /* We remove pp_es[i_new_es_member] and not pp_es[i] because the
 684          * list will be emptied starting from the end */
 685         input_DelES( p_input,
 686                      p_input->stream.pp_programs[0]->pp_es[i_new_es_number] );
 687     }
 688
 689     msg_Dbg( p_input, "the stream map after the PSM is now:" );
 690     input_DumpStream( p_input );
 691
 692     vlc_mutex_unlock( &p_input->stream.stream_lock );
 693 }
 694
 695 /*****************************************************************************
 696  * ReadPS: store a PS packet into a data_buffer_t
 697  *****************************************************************************/
 698 #define PEEK( SIZE )                                                        \
 699     i_error = input_Peek( p_input, &p_peek, SIZE );                         \
 700     if( i_error == -1 )                                                     \
 701     {                                                                       \
 702         return( -1 );                                                       \
 703     }                                                                       \
 704     else if( i_error < SIZE )                                               \
 705     {                                                                       \
 706         /* EOF */                                                           \
 707         return( 0 );                                                        \
 708     }
 709
 710 static ssize_t ReadPS( input_thread_t * p_input, data_packet_t ** pp_data )
 711 {
 712     byte_t *            p_peek;
 713     size_t              i_packet_size;
 714     ssize_t             i_error, i_read;
 715
 716     /* Read what we believe to be a packet header. */
 717     PEEK( 4 );
 718
 719     if( p_peek[0] || p_peek[1] || p_peek[2] != 1 || p_peek[3] < 0xB9 )
 720     {
 721         if( p_peek[0] || p_peek[1] || p_peek[2] )
 722         {
 723             /* It is common for MPEG-1 streams to pad with zeros
 724              * (although it is forbidden by the recommendation), so
 725              * don't bother everybody in this case. */
 726             msg_Warn( p_input, "garbage (0x%.2x%.2x%.2x%.2x)",
 727                       p_peek[0], p_peek[1], p_peek[2], p_peek[3] );
 728         }
 729
 730         /* This is not the startcode of a packet. Read the stream
 731          * until we find one. */
 732         while( p_peek[0] || p_peek[1] || p_peek[2] != 1 || p_peek[3] < 0xB9 )
 733         {
 734             p_input->p_current_data++;
 735             PEEK( 4 );
 736             if( p_input->b_die ) return( -1 );
 737         }
 738         /* Packet found. */
 739     }
 740
 741     /* 0x1B9 == SYSTEM_END_CODE, it is only 4 bytes long. */
 742     if( p_peek[3] != 0xB9 )
 743     {
 744         /* The packet is at least 6 bytes long. */
 745         PEEK( 6 );
 746
 747         if( p_peek[3] != 0xBA )
 748         {
 749             /* That's the case for all packets, except pack header. */
 750             i_packet_size = (p_peek[4] << 8) | p_peek[5];
 751         }
 752         else
 753         {
 754             /* Pack header. */
 755             if( (p_peek[4] & 0xC0) == 0x40 )
 756             {
 757                 /* MPEG-2 */
 758                 i_packet_size = 8;
 759             }
 760             else if( (p_peek[4] & 0xF0) == 0x20 )
 761             {
 762                 /* MPEG-1 */
 763                 i_packet_size = 6;
 764             }
 765             else
 766             {
 767                 msg_Err( p_input, "unable to determine stream type" );
 768                 return( -1 );
 769             }
 770         }
 771     }
 772     else
 773     {
 774         /* System End Code */
 775         i_packet_size = -2;
 776     }
 777
 778     /* Fetch a packet of the appropriate size. */
 779     i_read = input_SplitBuffer( p_input, pp_data, i_packet_size + 6 );
 780     if( i_read <= 0 )
 781     {
 782         return( i_read );
 783     }
 784
 785     /* In MPEG-2 pack headers we still have to read stuffing bytes. */
 786     if( ((*pp_data)->p_demux_start[3] == 0xBA) && (i_packet_size == 8) )
 787     {
 788         size_t i_stuffing = ((*pp_data)->p_demux_start[13] & 0x7);
 789         /* Force refill of the input buffer - though we don't care
 790          * about p_peek. Please note that this is unoptimized. */
 791         PEEK( i_stuffing );
 792         p_input->p_current_data += i_stuffing;
 793     }
 794
 795     return( 1 );
 796 }
 797
 798 #undef PEEK
 799
 800 /*****************************************************************************
 801  * ParsePS: read the PS header
 802  *****************************************************************************/
 803 static es_descriptor_t * ParsePS( input_thread_t * p_input,
 804                                   data_packet_t * p_data )
 805 {
 806     u32                 i_code;
 807     es_descriptor_t *   p_es = NULL;
 808
 809     i_code = p_data->p_demux_start[3];
 810
 811     if( i_code > 0xBC ) /* ES start code */
 812     {
 813         u16                 i_id;
 814         int                 i_dummy;
 815
 816         /* This is a PES packet. Find out if we want it or not. */
 817         i_id = GetID( p_data );
 818
 819         vlc_mutex_lock( &p_input->stream.stream_lock );
 820         if( p_input->stream.pp_programs[0]->b_is_ok )
 821         {
 822             /* Look only at the selected ES. */
 823             for( i_dummy = 0; i_dummy < p_input->stream.i_selected_es_number;
 824                  i_dummy++ )
 825             {
 826                 if( p_input->stream.pp_selected_es[i_dummy] != NULL
 827                     && p_input->stream.pp_selected_es[i_dummy]->i_id == i_id )
 828                 {
 829                     p_es = p_input->stream.pp_selected_es[i_dummy];
 830                     break;
 831                 }
 832             }
 833         }
 834         else
 835         {
 836             stream_ps_data_t * p_demux =
 837               (stream_ps_data_t *)p_input->stream.pp_programs[0]->p_demux_data;
 838
 839             /* Search all ES ; if not found -> AddES */
 840             p_es = input_FindES( p_input, i_id );
 841
 842             if( p_es == NULL && !p_demux->b_has_PSM )
 843             {
 844                 p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
 845                                     i_id, 0 );
 846                 if( p_es != NULL )
 847                 {
 848                     p_es->i_stream_id = p_data->p_demux_start[3];
 849
 850                     /* Set stream type and auto-spawn. */
 851                     if( (i_id & 0xF0) == 0xE0 )
 852                     {
 853                         /* MPEG video */
 854                         p_es->i_fourcc = VLC_FOURCC('m','p','g','v');
 855                         p_es->i_cat = VIDEO_ES;
 856 #ifdef AUTO_SPAWN
 857                         if( !p_input->stream.b_seekable )
 858                             input_SelectES( p_input, p_es );
 859 #endif
 860                     }
 861                     else if( (i_id & 0xE0) == 0xC0 )
 862                     {
 863                         /* MPEG audio */
 864                         p_es->i_fourcc = VLC_FOURCC('m','p','g','a');
 865                         p_es->i_cat = AUDIO_ES;
 866 #ifdef AUTO_SPAWN
 867                         if( !p_input->stream.b_seekable )
 868                         if( config_GetInt( p_input, "audio-channel" )
 869                                 == (p_es->i_id & 0x1F) ||
 870                             ( config_GetInt( p_input, "audio-channel" ) < 0
 871                               && !(p_es->i_id & 0x1F) ) )
 872                         switch( config_GetInt( p_input, "audio-type" ) )
 873                         {
 874                         case -1:
 875                         case REQUESTED_MPEG:
 876                             input_SelectES( p_input, p_es );
 877                         }
 878 #endif
 879                     }
 880                     else if( (i_id & 0xF0FF) == 0x80BD )
 881                     {
 882                         /* A52 audio (0x80->0x8F) */
 883                         p_es->i_fourcc = VLC_FOURCC('a','5','2','b');
 884                         p_es->i_cat = AUDIO_ES;
 885 #ifdef AUTO_SPAWN
 886                         if( !p_input->stream.b_seekable )
 887                         if( config_GetInt( p_input, "audio-channel" )
 888                                 == ((p_es->i_id & 0xF00) >> 8) ||
 889                             ( config_GetInt( p_input, "audio-channel" ) < 0
 890                               && !((p_es->i_id & 0xF00) >> 8)) )
 891                         switch( config_GetInt( p_input, "audio-type" ) )
 892                         {
 893                         case -1:
 894                         case REQUESTED_A52:
 895                             input_SelectES( p_input, p_es );
 896                         }
 897 #endif
 898                     }
 899                     else if( (i_id & 0xE0FF) == 0x20BD )
 900                     {
 901                         /* Subtitles video (0x20->0x3F) */
 902                         p_es->i_fourcc = VLC_FOURCC('s','p','u','b');
 903                         p_es->i_cat = SPU_ES;
 904 #ifdef AUTO_SPAWN
 905                         if( config_GetInt( p_input, "spu-channel" )
 906                                 == ((p_es->i_id & 0x1F00) >> 8) )
 907                         {
 908                             if( !p_input->stream.b_seekable )
 909                                 input_SelectES( p_input, p_es );
 910                         }
 911 #endif
 912                     }
 913                     else if( (i_id & 0xF0FF) == 0xA0BD )
 914                     {
 915                         /* LPCM audio (0xA0->0xAF) */
 916                         p_es->i_fourcc = VLC_FOURCC('l','p','c','b');
 917                         p_es->i_cat = AUDIO_ES;
 918                     }
 919                     else
 920                     {
 921                         p_es->i_fourcc = 0;
 922                     }
 923                 }
 924
 925                 /* Tell the interface the stream has changed */
 926                 p_input->stream.b_changed = 1;
 927             }
 928         } /* stream.b_is_ok */
 929         vlc_mutex_unlock( &p_input->stream.stream_lock );
 930     } /* i_code > 0xBC */
 931
 932     return( p_es );
 933 }
 934
 935 /*****************************************************************************
 936  * DemuxPS: first step of demultiplexing: the PS header
 937  *****************************************************************************/
 938 static void DemuxPS( input_thread_t * p_input, data_packet_t * p_data )
 939 {
 940     u32                 i_code;
 941     vlc_bool_t          b_trash = 0;
 942     es_descriptor_t *   p_es = NULL;
 943
 944     i_code = ((u32)p_data->p_demux_start[0] << 24)
 945                 | ((u32)p_data->p_demux_start[1] << 16)
 946                 | ((u32)p_data->p_demux_start[2] << 8)
 947                 | p_data->p_demux_start[3];
 948     if( i_code <= 0x1BC )
 949     {
 950         switch( i_code )
 951         {
 952         case 0x1BA: /* PACK_START_CODE */
 953             {
 954                 /* Read the SCR. */
 955                 mtime_t         scr_time;
 956                 u32             i_mux_rate;
 957
 958                 if( (p_data->p_demux_start[4] & 0xC0) == 0x40 )
 959                 {
 960                     /* MPEG-2 */
 961                     byte_t      p_header[14];
 962                     byte_t *    p_byte;
 963                     p_byte = p_data->p_demux_start;
 964
 965                     if( MoveChunk( p_header, &p_data, &p_byte, 14 ) != 14 )
 966                     {
 967                         msg_Warn( p_input,
 968                                   "packet too short to have a header" );
 969                         b_trash = 1;
 970                         break;
 971                     }
 972                     scr_time =
 973                          ((mtime_t)(p_header[4] & 0x38) << 27) |
 974                          ((mtime_t)(U32_AT(p_header + 4) & 0x03FFF800)
 975                                         << 4) |
 976                          ((( ((mtime_t)U16_AT(p_header + 6) << 16)
 977                             | (mtime_t)U16_AT(p_header + 8) ) & 0x03FFF800)
 978                                         >> 11);
 979
 980                     /* mux_rate */
 981                     i_mux_rate = ((u32)U16_AT(p_header + 10) << 6)
 982                                    | (p_header[12] >> 2);
 983                     /* FIXME FIXME FIXME FIXME FIXME FIXME FIXME FIXME
 984                      * This is the biggest kludge ever !
 985                      * I don't know what's wrong with mux_rate calculation
 986                      * but this heuristic works well : */
 987                     i_mux_rate <<= 1;
 988                     i_mux_rate /= 3;
 989                 }
 990                 else
 991                 {
 992                     /* MPEG-1 SCR is like PTS. */
 993                     byte_t      p_header[12];
 994                     byte_t *    p_byte;
 995                     p_byte = p_data->p_demux_start;
 996
 997                     if( MoveChunk( p_header, &p_data, &p_byte, 12 ) != 12 )
 998                     {
 999                         msg_Warn( p_input,
1000                                   "packet too short to have a header" );
1001                         b_trash = 1;
1002                         break;
1003                     }
1004                     scr_time =
1005                          ((mtime_t)(p_header[4] & 0x0E) << 29) |
1006                          (((mtime_t)U32_AT(p_header + 4) & 0xFFFE00) << 6) |
1007                          ((mtime_t)p_header[7] << 7) |
1008                          ((mtime_t)p_header[8] >> 1);
1009
1010                     /* mux_rate */
1011                     i_mux_rate = (U32_AT(p_header + 8) & 0x7FFFFE) >> 1;
1012                 }
1013                 /* Call the pace control. */
1014                 input_ClockManageRef( p_input,
1015                                       p_input->stream.p_selected_program,
1016                                       scr_time );
1017
1018                 if( i_mux_rate != p_input->stream.i_mux_rate
1019                      && p_input->stream.i_mux_rate )
1020                 {
1021                     msg_Warn( p_input,
1022                               "mux_rate changed, expect cosmetic errors" );
1023                 }
1024                 p_input->stream.i_mux_rate = i_mux_rate;
1025
1026                 b_trash = 1;
1027             }
1028             break;
1029
1030         case 0x1BB: /* SYSTEM_START_CODE */
1031             b_trash = 1;                              /* Nothing interesting */
1032             break;
1033
1034         case 0x1BC: /* PROGRAM_STREAM_MAP_CODE */
1035             DecodePSM( p_input, p_data );
1036             b_trash = 1;
1037             break;
1038
1039         case 0x1B9: /* PROGRAM_END_CODE */
1040             b_trash = 1;
1041             break;
1042
1043         default:
1044             /* This should not happen */
1045             b_trash = 1;
1046             msg_Warn( p_input, "unwanted packet received "
1047                                "with startcode 0x%.8x", i_code );
1048         }
1049     }
1050     else
1051     {
1052         p_es = ParsePS( p_input, p_data );
1053
1054         vlc_mutex_lock( &p_input->stream.control.control_lock );
1055         if( p_es != NULL && p_es->p_decoder_fifo != NULL
1056              && (p_es->i_cat != AUDIO_ES || !p_input->stream.control.b_mute) )
1057         {
1058             vlc_mutex_unlock( &p_input->stream.control.control_lock );
1059             p_es->c_packets++;
1060             GatherPES( p_input, p_data, p_es, 1, 0 );
1061         }
1062         else
1063         {
1064             vlc_mutex_unlock( &p_input->stream.control.control_lock );
1065             b_trash = 1;
1066         }
1067     }
1068
1069     /* Trash the packet if it has no payload or if it isn't selected */
1070     if( b_trash )
1071     {
1072         input_DeletePacket( p_input->p_method_data, p_data );
1073         p_input->stream.c_packets_trashed++;
1074     }
1075 }
1076
1077
1078 /*
1079  * TS Demultiplexing
1080  */
1081
1082 /*****************************************************************************
1083  * ReadTS: store a TS packet into a data_buffer_t
1084  *****************************************************************************/
1085 #define PEEK( SIZE )                                                        \
1086     i_error = input_Peek( p_input, &p_peek, SIZE );                         \
1087     if( i_error == -1 )                                                     \
1088     {                                                                       \
1089         return( -1 );                                                       \
1090     }                                                                       \
1091     else if( i_error < SIZE )                                               \
1092     {                                                                       \
1093         /* EOF */                                                           \
1094         return( 0 );                                                        \
1095     }
1096
1097 static ssize_t ReadTS( input_thread_t * p_input, data_packet_t ** pp_data )
1098 {
1099     byte_t *            p_peek;
1100     ssize_t             i_error, i_read;
1101
1102     PEEK( 1 );
1103
1104     if( *p_peek != TS_SYNC_CODE )
1105     {
1106         msg_Warn( p_input, "garbage at input (%x)", *p_peek );
1107
1108         if( p_input->i_mtu )
1109         {
1110             while( *p_peek != TS_SYNC_CODE )
1111             {
1112                 /* Try to resync on next packet. */
1113                 PEEK( TS_PACKET_SIZE );
1114                 p_input->p_current_data += TS_PACKET_SIZE;
1115                 PEEK( 1 );
1116             }
1117         }
1118         else
1119         {
1120             /* Move forward until we find 0x47 (and hope it's the good
1121              * one... FIXME) */
1122             while( *p_peek != TS_SYNC_CODE )
1123             {
1124                 p_input->p_current_data++;
1125                 PEEK( 1 );
1126             }
1127         }
1128     }
1129
1130     i_read = input_SplitBuffer( p_input, pp_data, TS_PACKET_SIZE );
1131     if( i_read <= 0 )
1132     {
1133         return( i_read );
1134     }
1135
1136     return( 1 );
1137 }
1138
1139 /*****************************************************************************
1140  * DemuxTS: first step of demultiplexing: the TS header
1141  *****************************************************************************/
1142 static void DemuxTS( input_thread_t * p_input, data_packet_t * p_data,
1143                      psi_callback_t pf_psi_callback )
1144 {
1145     u16                 i_pid;
1146     int                 i_dummy;
1147     vlc_bool_t          b_adaptation;         /* Adaptation field is present */
1148     vlc_bool_t          b_payload;                 /* Packet carries payload */
1149     vlc_bool_t          b_unit_start;  /* A PSI or a PES start in the packet */
1150     vlc_bool_t          b_trash = 0;             /* Is the packet unuseful ? */
1151     vlc_bool_t          b_lost = 0;             /* Was there a packet loss ? */
1152     vlc_bool_t          b_psi = 0;                        /* Is this a PSI ? */
1153     vlc_bool_t          b_pcr = 0;                   /* Does it have a PCR ? */
1154     es_descriptor_t *   p_es = NULL;
1155     es_ts_data_t *      p_es_demux = NULL;
1156     pgrm_ts_data_t *    p_pgrm_demux = NULL;
1157
1158 #define p (p_data->p_demux_start)
1159     /* Extract flags values from TS common header. */
1160     i_pid = ((p[1] & 0x1F) << 8) | p[2];
1161     b_unit_start = (p[1] & 0x40);
1162     b_adaptation = (p[3] & 0x20);
1163     b_payload = (p[3] & 0x10);
1164
1165     /* Find out the elementary stream. */
1166     vlc_mutex_lock( &p_input->stream.stream_lock );
1167
1168     for( i_dummy = 0; i_dummy < p_input->stream.i_pgrm_number; i_dummy ++ )
1169     {
1170         if( (( pgrm_ts_data_t * ) p_input->stream.pp_programs[i_dummy]->
1171                     p_demux_data)->i_pcr_pid == i_pid )
1172         {
1173             b_pcr = 1;
1174             break;
1175         }
1176     }
1177
1178     p_es= input_FindES( p_input, i_pid );
1179
1180     if( (p_es != NULL) && (p_es->p_demux_data != NULL) )
1181     {
1182         p_es_demux = (es_ts_data_t *)p_es->p_demux_data;
1183
1184         if( p_es_demux->b_psi )
1185         {
1186             b_psi = 1;
1187         }
1188         else
1189         {
1190             p_pgrm_demux = (pgrm_ts_data_t *)p_es->p_pgrm->p_demux_data;
1191         }
1192     }
1193
1194     vlc_mutex_lock( &p_input->stream.control.control_lock );
1195     if( ( p_es == NULL ) || (p_es->i_cat == AUDIO_ES
1196                               && p_input->stream.control.b_mute) )
1197     {
1198         /* Not selected. Just read the adaptation field for a PCR. */
1199         b_trash = 1;
1200     }
1201     else if( p_es->p_decoder_fifo == NULL && !b_psi )
1202     {
1203         b_trash = 1;
1204     }
1205
1206     vlc_mutex_unlock( &p_input->stream.control.control_lock );
1207     vlc_mutex_unlock( &p_input->stream.stream_lock );
1208
1209
1210     /* Don't change the order of the tests : if b_psi then p_pgrm_demux
1211      * may still be null. Who said it was ugly ?
1212      * I have written worse. --Meuuh */
1213     if( ( p_es  ) &&
1214         ((p_es->p_decoder_fifo != NULL) || b_psi || b_pcr ) )
1215     {
1216         p_es->c_packets++;
1217
1218         /* Extract adaptation field information if any */
1219
1220         if( !b_adaptation )
1221         {
1222             /* We don't have any adaptation_field, so payload starts
1223              * immediately after the 4 byte TS header */
1224             p_data->p_payload_start += 4;
1225         }
1226         else
1227         {
1228             /* p[4] is adaptation_field_length minus one */
1229             p_data->p_payload_start += 5 + p[4];
1230
1231             /* The adaptation field can be limited to the
1232              * adaptation_field_length byte, so that there is nothing to do:
1233              * skip this possibility */
1234             if( p[4] )
1235             {
1236                 /* If the packet has both adaptation_field and payload,
1237                  * adaptation_field cannot be more than 182 bytes long; if
1238                  * there is only an adaptation_field, it must fill the next
1239                  * 183 bytes. */
1240                 if( b_payload ? (p[4] > 182) : (p[4] != 183) )
1241                 {
1242                     msg_Warn( p_input, "invalid TS adaptation field (%p)",
1243                               p_data );
1244                     p_data->b_discard_payload = 1;
1245                     p_es->c_invalid_packets++;
1246                 }
1247
1248                 /* Now we are sure that the byte containing flags is present:
1249                  * read it */
1250                 else
1251                 {
1252                     /* discontinuity_indicator */
1253                     if( p[5] & 0x80 )
1254                     {
1255                         msg_Warn( p_input,
1256                             "discontinuity_indicator encountered by TS demux "
1257                             "(position read: %d, saved: %d)",
1258                             p[5] & 0x80, p_es_demux->i_continuity_counter );
1259
1260                         /* If the PID carries the PCR, there will be a system
1261                          * time-based discontinuity. We let the PCR decoder
1262                          * handle that. */
1263                         p_es->p_pgrm->i_synchro_state = SYNCHRO_REINIT;
1264
1265                         /* There also may be a continuity_counter
1266                          * discontinuity: resynchronize our counter with
1267                          * the one of the stream. */
1268                         p_es_demux->i_continuity_counter = (p[3] & 0x0f) - 1;
1269                     }
1270
1271                 } /* valid TS adaptation field ? */
1272             } /* length > 0 */
1273         } /* has adaptation field */
1274         /* Check the continuity of the stream. */
1275         i_dummy = ((p[3] & 0x0f) - p_es_demux->i_continuity_counter) & 0x0f;
1276         if( i_dummy == 1 )
1277         {
1278             /* Everything is ok, just increase our counter */
1279             (p_es_demux->i_continuity_counter)++;
1280         }
1281         else
1282         {
1283             if( !b_payload && i_dummy == 0 )
1284             {
1285                 /* This is a packet without payload, this is allowed by the
1286                  * draft. As there is nothing interesting in this packet
1287                  * (except PCR that have already been handled), we can trash
1288                  * the packet. */
1289                 b_trash = 1;
1290             }
1291             else if( i_dummy <= 0 )
1292             {
1293                 /* Duplicate packet: mark it as being to be trashed. */
1294                 msg_Warn( p_input,
1295                           "duplicate packet received by TS demux (%d)",
1296                           i_dummy );
1297                 b_trash = 1;
1298             }
1299             else if( p_es_demux->i_continuity_counter == 0xFF )
1300             {
1301                 /* This means that the packet is the first one we receive for
1302                  * this ES since the continuity counter ranges between 0 and
1303                  * 0x0F excepts when it has been initialized by the input:
1304                  * init the counter to the correct value. */
1305                 msg_Warn( p_input, "first packet for PID %d received "
1306                                    "by TS demux", p_es->i_id );
1307                 p_es_demux->i_continuity_counter = (p[3] & 0x0f);
1308             }
1309             else
1310             {
1311                 /* This can indicate that we missed a packet or that the
1312                  * continuity_counter wrapped and we received a dup packet:
1313                  * as we don't know, do as if we missed a packet to be sure
1314                  * to recover from this situation */
1315                 msg_Warn( p_input,
1316                           "packet lost by TS demux: current %d, packet %d",
1317                           p_es_demux->i_continuity_counter & 0x0f,
1318                           p[3] & 0x0f );
1319                 b_lost = 1;
1320                 p_es_demux->i_continuity_counter = p[3] & 0x0f;
1321             } /* not continuous */
1322         } /* continuity */
1323     } /* if selected or PCR */
1324
1325     /* Handle PCR */
1326     if( b_pcr && b_adaptation && (p[5] & 0x10) && p[4]>=7 )
1327     {
1328         /* Read the PCR. */
1329         mtime_t     pcr_time;
1330         pcr_time = ( (mtime_t)p[6] << 25 ) |
1331                    ( (mtime_t)p[7] << 17 ) |
1332                    ( (mtime_t)p[8] << 9 ) |
1333                    ( (mtime_t)p[9] << 1 ) |
1334                    ( (mtime_t)p[10] >> 7 );
1335         /* Call the pace control. */
1336         for( i_dummy = 0; i_dummy < p_input->stream.i_pgrm_number;
1337                                 i_dummy ++ )
1338         {
1339             if( ( ( pgrm_ts_data_t * ) p_input->stream.pp_programs[i_dummy]->
1340                         p_demux_data )->i_pcr_pid == i_pid )
1341             {
1342                 input_ClockManageRef( p_input,
1343                     p_input->stream.pp_programs[i_dummy], pcr_time );
1344             }
1345         }
1346
1347     }
1348
1349     /* Trash the packet if it has no payload or if it isn't selected */
1350     if( b_trash )
1351     {
1352         input_DeletePacket( p_input->p_method_data, p_data );
1353         p_input->stream.c_packets_trashed++;
1354     }
1355     else
1356     {
1357         if( b_psi )
1358         {
1359             /* The payload contains PSI tables */
1360             (* pf_psi_callback) ( p_input, p_data, p_es, b_unit_start );
1361         }
1362         else
1363         {
1364             /* The payload carries a PES stream */
1365             GatherPES( p_input, p_data, p_es, b_unit_start, b_lost );
1366         }
1367
1368     }
1369
1370 #undef p
1371
1372 }
1373