git.sesse.net Git - vlc/blob - plugins/mpeg/input_ps.c

   1 /*****************************************************************************
   2  * input_ps.c: PS demux and packet management
   3  *****************************************************************************
   4  * Copyright (C) 1998, 1999, 2000 VideoLAN
   5  * $Id: input_ps.c,v 1.19 2001/04/27 23:29:14 stef Exp $
   6  *
   7  * Authors: Christophe Massiot <massiot@via.ecp.fr>
   8  *          Cyril Deguet <asmax@via.ecp.fr>
   9  *
  10  * This program is free software; you can redistribute it and/or modify
  11  * it under the terms of the GNU General Public License as published by
  12  * the Free Software Foundation; either version 2 of the License, or
  13  * (at your option) any later version.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License
  21  * along with this program; if not, write to the Free Software
  22  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  23  *****************************************************************************/
  24
  25 #define MODULE_NAME ps
  26 #include "modules_inner.h"
  27
  28 /*****************************************************************************
  29  * Preamble
  30  *****************************************************************************/
  31 #include "defs.h"
  32
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <errno.h>
  36
  37 #include <sys/types.h>
  38 #include <sys/stat.h>
  39 #include <unistd.h>
  40 #include <fcntl.h>
  41
  42 #include "config.h"
  43 #include "common.h"
  44 #include "threads.h"
  45 #include "mtime.h"
  46 #include "tests.h"
  47
  48 #include "intf_msg.h"
  49
  50 #include "main.h"
  51
  52 #include "stream_control.h"
  53 #include "input_ext-intf.h"
  54 #include "input_ext-dec.h"
  55
  56 #include "input.h"
  57
  58 #include "input_ps.h"
  59 #include "mpeg_system.h"
  60
  61 #include "debug.h"
  62
  63 #include "modules.h"
  64
  65 /*****************************************************************************
  66  * Local prototypes
  67  *****************************************************************************/
  68 static int  PSProbe     ( probedata_t * );
  69 static int  PSRead      ( struct input_thread_s *,
  70                           data_packet_t * p_packets[INPUT_READ_ONCE] );
  71 static void PSInit      ( struct input_thread_s * );
  72 static void PSEnd       ( struct input_thread_s * );
  73 static void PSSeek      ( struct input_thread_s *, off_t );
  74 static struct pes_packet_s *  NewPES    ( void * );
  75 static struct data_packet_s * NewPacket ( void *, size_t );
  76 static void DeletePacket( void *, struct data_packet_s * );
  77 static void DeletePES   ( void *, struct pes_packet_s * );
  78
  79 /*****************************************************************************
  80  * Functions exported as capabilities. They are declared as static so that
  81  * we don't pollute the namespace too much.
  82  *****************************************************************************/
  83 void _M( input_getfunctions )( function_list_t * p_function_list )
  84 {
  85 #define input p_function_list->functions.input
  86     p_function_list->pf_probe = PSProbe;
  87     input.pf_init             = PSInit;
  88     input.pf_open             = input_FileOpen;
  89     input.pf_close            = input_FileClose;
  90     input.pf_end              = PSEnd;
  91     input.pf_set_area         = NULL;
  92     input.pf_read             = PSRead;
  93     input.pf_demux            = input_DemuxPS;
  94     input.pf_new_packet       = NewPacket;
  95     input.pf_new_pes          = NewPES;
  96     input.pf_delete_packet    = DeletePacket;
  97     input.pf_delete_pes       = DeletePES;
  98     input.pf_rewind           = NULL;
  99     input.pf_seek             = PSSeek;
 100 #undef input
 101 }
 102
 103 /*
 104  * Data reading functions
 105  */
 106
 107 /*****************************************************************************
 108  * PSProbe: verifies that the stream is a PS stream
 109  *****************************************************************************/
 110 static int PSProbe( probedata_t *p_data )
 111 {
 112     input_thread_t * p_input = (input_thread_t *)p_data;
 113
 114     char * psz_name = p_input->p_source;
 115     int i_handle;
 116     int i_score = 10;
 117
 118     if( TestMethod( INPUT_METHOD_VAR, "ps" ) )
 119     {
 120         return( 999 );
 121     }
 122
 123     if( ( strlen(psz_name) > 5 ) && !strncasecmp( psz_name, "file:", 5 ) )
 124     {
 125         /* If the user specified "file:" then it's probably a file */
 126         i_score = 100;
 127         psz_name += 5;
 128     }
 129
 130     i_handle = open( psz_name, 0 );
 131     if( i_handle == -1 )
 132     {
 133         return( 0 );
 134     }
 135     close( i_handle );
 136
 137     return( i_score );
 138 }
 139
 140 /*****************************************************************************
 141  * PSInit: initializes PS structures
 142  *****************************************************************************/
 143 static void PSInit( input_thread_t * p_input )
 144 {
 145     thread_ps_data_t *  p_method;
 146     packet_cache_t *    p_packet_cache;
 147
 148     if( (p_method =
 149          (thread_ps_data_t *)malloc( sizeof(thread_ps_data_t) )) == NULL )
 150     {
 151         intf_ErrMsg( "Out of memory" );
 152         p_input->b_error = 1;
 153         return;
 154     }
 155     p_input->p_plugin_data = (void *)p_method;
 156
 157     /* creates the packet cache structure */
 158     p_packet_cache = malloc( sizeof(packet_cache_t) );
 159     if ( p_packet_cache == NULL )
 160     {
 161         intf_ErrMsg( "Out of memory" );
 162         p_input->b_error = 1;
 163         return;
 164     }
 165     p_input->p_method_data = (void *)p_packet_cache;
 166
 167     /* allocates the data cache */
 168     p_packet_cache->data.p_stack = malloc( DATA_CACHE_SIZE *
 169         sizeof(data_packet_t*) );
 170     if ( p_packet_cache->data.p_stack == NULL )
 171     {
 172         intf_ErrMsg( "Out of memory" );
 173         p_input->b_error = 1;
 174         return;
 175     }
 176     p_packet_cache->data.l_index = 0;
 177
 178     /* allocates the PES cache */
 179     p_packet_cache->pes.p_stack = malloc( PES_CACHE_SIZE *
 180         sizeof(pes_packet_t*) );
 181     if ( p_packet_cache->pes.p_stack == NULL )
 182     {
 183         intf_ErrMsg( "Out of memory" );
 184         p_input->b_error = 1;
 185         return;
 186     }
 187     p_packet_cache->pes.l_index = 0;
 188
 189     /* allocates the small buffer cache */
 190     p_packet_cache->small.p_stack = malloc( SMALL_CACHE_SIZE *
 191         sizeof(packet_buffer_t) );
 192     if ( p_packet_cache->small.p_stack == NULL )
 193     {
 194         intf_ErrMsg( "Out of memory" );
 195         p_input->b_error = 1;
 196         return;
 197     }
 198     p_packet_cache->small.l_index = 0;
 199
 200     /* allocates the large buffer cache */
 201     p_packet_cache->large.p_stack = malloc( LARGE_CACHE_SIZE *
 202         sizeof(packet_buffer_t) );
 203     if ( p_packet_cache->large.p_stack == NULL )
 204     {
 205         intf_ErrMsg( "Out of memory" );
 206         p_input->b_error = 1;
 207         return;
 208     }
 209     p_packet_cache->large.l_index = 0;
 210
 211     /* Re-open the socket as a buffered FILE stream */
 212     if( (p_method->stream = fdopen( p_input->i_handle, "r" )) == NULL )
 213     {
 214         intf_ErrMsg( "Cannot open file (%s)", strerror(errno) );
 215         p_input->b_error = 1;
 216         return;
 217     }
 218     rewind( p_method->stream );
 219
 220     /* FIXME : detect if InitStream failed */
 221     input_InitStream( p_input, sizeof( stream_ps_data_t ) );
 222     input_AddProgram( p_input, 0, sizeof( stream_ps_data_t ) );
 223
 224     if( p_input->stream.b_seekable )
 225     {
 226         stream_ps_data_t * p_demux_data =
 227              (stream_ps_data_t *)p_input->stream.pp_programs[0]->p_demux_data;
 228
 229         /* Pre-parse the stream to gather stream_descriptor_t. */
 230         p_input->stream.pp_programs[0]->b_is_ok = 0;
 231         p_demux_data->i_PSM_version = EMPTY_PSM_VERSION;
 232
 233         while( !p_input->b_die && !p_input->b_error
 234                 && !p_demux_data->b_has_PSM )
 235         {
 236             int                 i_result, i;
 237             data_packet_t *     pp_packets[INPUT_READ_ONCE];
 238
 239             i_result = PSRead( p_input, pp_packets );
 240             if( i_result == 1 )
 241             {
 242                 /* EOF */
 243                 vlc_mutex_lock( &p_input->stream.stream_lock );
 244                 p_input->stream.pp_programs[0]->b_is_ok = 1;
 245                 vlc_mutex_unlock( &p_input->stream.stream_lock );
 246                 break;
 247             }
 248             if( i_result == -1 )
 249             {
 250                 p_input->b_error = 1;
 251                 break;
 252             }
 253
 254             for( i = 0; i < INPUT_READ_ONCE && pp_packets[i] != NULL; i++ )
 255             {
 256                 /* FIXME: use i_p_config_t */
 257                 input_ParsePS( p_input, pp_packets[i] );
 258                 DeletePacket( p_input->p_method_data, pp_packets[i] );
 259             }
 260
 261             /* File too big. */
 262             if( p_input->stream.p_selected_area->i_tell >
 263                                                     INPUT_PREPARSE_LENGTH )
 264             {
 265                 break;
 266             }
 267         }
 268         rewind( p_method->stream );
 269         vlc_mutex_lock( &p_input->stream.stream_lock );
 270
 271         p_input->stream.i_method = INPUT_METHOD_FILE;
 272         p_input->stream.p_selected_area->i_tell = 0;
 273
 274         if( p_demux_data->b_has_PSM )
 275         {
 276             /* (The PSM decoder will care about spawning the decoders) */
 277             p_input->stream.pp_programs[0]->b_is_ok = 1;
 278         }
 279 #ifdef AUTO_SPAWN
 280         else
 281         {
 282             /* (We have to do it ourselves) */
 283             int                 i_es;
 284
 285             /* FIXME: we should do multiple passes in case an audio type
 286              * is not present */
 287             for( i_es = 0;
 288                  i_es < p_input->stream.pp_programs[0]->i_es_number;
 289                  i_es++ )
 290             {
 291 #define p_es p_input->stream.pp_programs[0]->pp_es[i_es]
 292                 switch( p_es->i_type )
 293                 {
 294                     case MPEG1_VIDEO_ES:
 295                     case MPEG2_VIDEO_ES:
 296                         input_SelectES( p_input, p_es );
 297                         break;
 298
 299                     case MPEG1_AUDIO_ES:
 300                     case MPEG2_AUDIO_ES:
 301                         if( main_GetIntVariable( INPUT_CHANNEL_VAR, 0 )
 302                                 == (p_es->i_id & 0x1F) )
 303                         switch( main_GetIntVariable( INPUT_AUDIO_VAR, 0 ) )
 304                         {
 305                         case 0:
 306                             main_PutIntVariable( INPUT_AUDIO_VAR,
 307                                                  REQUESTED_MPEG );
 308                         case REQUESTED_MPEG:
 309                             input_SelectES( p_input, p_es );
 310                         }
 311                         break;
 312
 313                     case AC3_AUDIO_ES:
 314                         if( main_GetIntVariable( INPUT_CHANNEL_VAR, 0 )
 315                                 == ((p_es->i_id & 0xF00) >> 8) )
 316                         switch( main_GetIntVariable( INPUT_AUDIO_VAR, 0 ) )
 317                         {
 318                         case 0:
 319                             main_PutIntVariable( INPUT_AUDIO_VAR,
 320                                                  REQUESTED_AC3 );
 321                         case REQUESTED_AC3:
 322                             input_SelectES( p_input, p_es );
 323                         }
 324                         break;
 325
 326                     case DVD_SPU_ES:
 327                         if( main_GetIntVariable( INPUT_SUBTITLE_VAR, -1 )
 328                                 == ((p_es->i_id & 0x1F00) >> 8) )
 329                         {
 330                             input_SelectES( p_input, p_es );
 331                         }
 332                         break;
 333
 334                     case LPCM_AUDIO_ES:
 335                         /* FIXME ! */
 336                         break;
 337                 }
 338             }
 339
 340         }
 341 #endif
 342 #ifdef STATS
 343         input_DumpStream( p_input );
 344 #endif
 345         vlc_mutex_unlock( &p_input->stream.stream_lock );
 346     }
 347     else
 348     {
 349         /* The programs will be added when we read them. */
 350         vlc_mutex_lock( &p_input->stream.stream_lock );
 351         p_input->stream.i_method = INPUT_METHOD_FILE;
 352         p_input->stream.pp_programs[0]->b_is_ok = 0;
 353         vlc_mutex_unlock( &p_input->stream.stream_lock );
 354     }
 355 }
 356
 357 /*****************************************************************************
 358  * PSEnd: frees unused data
 359  *****************************************************************************/
 360 static void PSEnd( input_thread_t * p_input )
 361 {
 362     free( p_input->p_plugin_data );
 363 }
 364
 365 /*****************************************************************************
 366  * SafeRead: reads a chunk of stream and correctly detects errors
 367  *****************************************************************************/
 368 static __inline__ int SafeRead( input_thread_t * p_input, byte_t * p_buffer,
 369                                 size_t i_len )
 370 {
 371     thread_ps_data_t *  p_method;
 372     int                 i_error;
 373
 374     p_method = (thread_ps_data_t *)p_input->p_plugin_data;
 375     while( fread( p_buffer, i_len, 1, p_method->stream ) != 1 )
 376     {
 377         if( feof( p_method->stream ) )
 378         {
 379             return( 1 );
 380         }
 381
 382         if( (i_error = ferror( p_method->stream )) )
 383         {
 384             intf_ErrMsg( "Read failed (%s)", strerror(i_error) );
 385             return( -1 );
 386         }
 387     }
 388     vlc_mutex_lock( &p_input->stream.stream_lock );
 389     p_input->stream.p_selected_area->i_tell += i_len;
 390     vlc_mutex_unlock( &p_input->stream.stream_lock );
 391     return( 0 );
 392 }
 393
 394 /*****************************************************************************
 395  * PSRead: reads data packets
 396  *****************************************************************************
 397  * Returns -1 in case of error, 0 if everything went well, and 1 in case of
 398  * EOF.
 399  *****************************************************************************/
 400 static int PSRead( input_thread_t * p_input,
 401                    data_packet_t * pp_packets[INPUT_READ_ONCE] )
 402 {
 403     byte_t              p_header[6];
 404     data_packet_t *     p_data;
 405     size_t              i_packet_size;
 406     int                 i_packet, i_error;
 407     thread_ps_data_t *  p_method;
 408
 409     p_method = (thread_ps_data_t *)p_input->p_plugin_data;
 410
 411     memset( pp_packets, 0, INPUT_READ_ONCE * sizeof(data_packet_t *) );
 412     for( i_packet = 0; i_packet < INPUT_READ_ONCE; i_packet++ )
 413     {
 414         /* Read what we believe to be a packet header. */
 415         if( (i_error = SafeRead( p_input, p_header, 6 )) )
 416         {
 417             return( i_error );
 418         }
 419
 420         if( (U32_AT(p_header) & 0xFFFFFF00) != 0x100L )
 421         {
 422             /* This is not the startcode of a packet. Read the stream
 423              * until we find one. */
 424             u32         i_startcode = U32_AT(p_header);
 425             int         i_dummy;
 426
 427             if( i_startcode )
 428             {
 429                 /* It is common for MPEG-1 streams to pad with zeros
 430                  * (although it is forbidden by the recommendation), so
 431                  * don't bother everybody in this case. */
 432                 intf_WarnMsg( 1, "Garbage at input (%.8x)", i_startcode );
 433             }
 434
 435             while( (i_startcode & 0xFFFFFF00) != 0x100L )
 436             {
 437                 i_startcode <<= 8;
 438                 if( (i_dummy = getc( p_method->stream )) != EOF )
 439                 {
 440                     i_startcode |= i_dummy;
 441                 }
 442                 else
 443                 {
 444                     return( 1 );
 445                 }
 446             }
 447             /* Packet found. */
 448             *(u32 *)p_header = U32_AT(&i_startcode);
 449             if( (i_error = SafeRead( p_input, p_header + 4, 2 )) )
 450             {
 451                 return( i_error );
 452             }
 453         }
 454
 455         if( U32_AT(p_header) != 0x1BA )
 456         {
 457             /* That's the case for all packets, except pack header. */
 458             i_packet_size = U16_AT(&p_header[4]);
 459         }
 460         else
 461         {
 462             /* Pack header. */
 463             if( (p_header[4] & 0xC0) == 0x40 )
 464             {
 465                 /* MPEG-2 */
 466                 i_packet_size = 8;
 467             }
 468             else if( (p_header[4] & 0xF0) == 0x20 )
 469             {
 470                 /* MPEG-1 */
 471                 i_packet_size = 6;
 472             }
 473             else
 474             {
 475                 intf_ErrMsg( "Unable to determine stream type" );
 476                 return( -1 );
 477             }
 478         }
 479
 480         /* Fetch a packet of the appropriate size. */
 481         if( (p_data = NewPacket( p_input->p_method_data, i_packet_size + 6 ))
 482             == NULL )
 483         {
 484             intf_ErrMsg( "Out of memory" );
 485             return( -1 );
 486         }
 487
 488         /* Copy the header we already read. */
 489         memcpy( p_data->p_buffer, p_header, 6 );
 490
 491         /* Read the remaining of the packet. */
 492         if( i_packet_size && (i_error =
 493                 SafeRead( p_input, p_data->p_buffer + 6, i_packet_size )) )
 494         {
 495             return( i_error );
 496         }
 497
 498         /* In MPEG-2 pack headers we still have to read stuffing bytes. */
 499         if( U32_AT(p_header) == 0x1BA )
 500         {
 501             if( i_packet_size == 8 && (p_data->p_buffer[13] & 0x7) != 0 )
 502             {
 503                 /* MPEG-2 stuffing bytes */
 504                 byte_t      p_garbage[8];
 505                 if( (i_error = SafeRead( p_input, p_garbage,
 506                                          p_data->p_buffer[13] & 0x7)) )
 507                 {
 508                     return( i_error );
 509                 }
 510             }
 511         }
 512
 513         /* Give the packet to the other input stages. */
 514         pp_packets[i_packet] = p_data;
 515     }
 516
 517     return( 0 );
 518 }
 519
 520 /*****************************************************************************
 521  * PSSeek: changes the stream position indicator
 522  *****************************************************************************/
 523 static void PSSeek( input_thread_t * p_input, off_t i_position )
 524 {
 525     thread_ps_data_t *  p_method;
 526
 527     p_method = (thread_ps_data_t *)p_input->p_plugin_data;
 528
 529     /* A little bourrin but should work for a while --Meuuh */
 530     fseeko( p_method->stream, i_position, SEEK_SET );
 531
 532     p_input->stream.p_selected_area->i_tell = i_position;
 533 }
 534
 535 /*
 536  * Packet management utilities
 537  */
 538
 539
 540 /*****************************************************************************
 541  * NewPacket: allocates a data packet
 542  *****************************************************************************/
 543 static struct data_packet_s * NewPacket( void * p_packet_cache,
 544                                          size_t l_size )
 545 {
 546     packet_cache_t *   p_cache;
 547     data_packet_t *    p_data;
 548     long               l_index;
 549
 550     p_cache = (packet_cache_t *)p_packet_cache;
 551
 552 #ifdef DEBUG
 553     if ( p_cache == NULL )
 554     {
 555         intf_ErrMsg( "PPacket cache not initialized" );
 556         return NULL;
 557     }
 558 #endif
 559
 560     /* Safety check */
 561     if( l_size > INPUT_MAX_PACKET_SIZE )
 562     {
 563         intf_ErrMsg( "Packet too big (%d)", l_size );
 564         return NULL;
 565     }
 566
 567     /* Checks whether the data cache is empty */
 568     if( p_cache->data.l_index == 0 )
 569     {
 570         /* Allocates a new packet */
 571         if ( (p_data = malloc( sizeof(data_packet_t) )) == NULL )
 572         {
 573             intf_ErrMsg( "Out of memory" );
 574             return NULL;
 575         }
 576 #ifdef TRACE_INPUT
 577         intf_DbgMsg( "PS input: data packet allocated" );
 578 #endif
 579     }
 580     else
 581     {
 582         /* Takes the packet out from the cache */
 583         if( (p_data = p_cache->data.p_stack[ -- p_cache->data.l_index ])
 584             == NULL )
 585         {
 586             intf_ErrMsg( "NULL packet in the data cache" );
 587             return NULL;
 588         }
 589     }
 590
 591     if( l_size < MAX_SMALL_SIZE )
 592     {
 593         /* Small buffer */
 594
 595         /* Checks whether the buffer cache is empty */
 596         if( p_cache->small.l_index == 0 )
 597         {
 598             /* Allocates a new packet */
 599             if ( (p_data->p_buffer = malloc( l_size )) == NULL )
 600             {
 601                 intf_DbgMsg( "Out of memory" );
 602                 free( p_data );
 603                 return NULL;
 604             }
 605 #ifdef TRACE_INPUT
 606             intf_DbgMsg( "PS input: small buffer allocated" );
 607 #endif
 608             p_data->l_size = l_size;
 609         }
 610         else
 611         {
 612             /* Takes the packet out from the cache */
 613             l_index = -- p_cache->small.l_index;
 614             if( (p_data->p_buffer = p_cache->small.p_stack[l_index].p_data)
 615                 == NULL )
 616             {
 617                 intf_ErrMsg( "NULL packet in the small buffer cache" );
 618                 free( p_data );
 619                 return NULL;
 620             }
 621                 /* Reallocates the packet if it is too small or too large */
 622             if( p_cache->small.p_stack[l_index].l_size < l_size ||
 623                 p_cache->small.p_stack[l_index].l_size > 2*l_size )
 624             {
 625                 p_data->p_buffer = realloc( p_data->p_buffer, l_size );
 626                 p_data->l_size = l_size;
 627             }
 628             else
 629             {
 630                 p_data->l_size = p_cache->small.p_stack[l_index].l_size;
 631             }
 632         }
 633     }
 634     else
 635     {
 636         /* Large buffer */
 637
 638         /* Checks whether the buffer cache is empty */
 639         if( p_cache->large.l_index == 0 )
 640         {
 641             /* Allocates a new packet */
 642             if ( (p_data->p_buffer = malloc( l_size )) == NULL )
 643             {
 644                 intf_ErrMsg( "Out of memory" );
 645                 free( p_data );
 646                 return NULL;
 647             }
 648 #ifdef TRACE_INPUT
 649             intf_DbgMsg( "PS input: large buffer allocated" );
 650 #endif
 651             p_data->l_size = l_size;
 652         }
 653         else
 654         {
 655             /* Takes the packet out from the cache */
 656             l_index = -- p_cache->large.l_index;
 657             if( (p_data->p_buffer = p_cache->large.p_stack[l_index].p_data)
 658                 == NULL )
 659             {
 660                 intf_ErrMsg( "NULL packet in the small buffer cache" );
 661                 free( p_data );
 662                 return NULL;
 663             }
 664                 /* Reallocates the packet if it is too small or too large */
 665             if( p_cache->large.p_stack[l_index].l_size < l_size ||
 666                 p_cache->large.p_stack[l_index].l_size > 2*l_size )
 667             {
 668                 p_data->p_buffer = realloc( p_data->p_buffer, l_size );
 669                 p_data->l_size = l_size;
 670             }
 671             else
 672             {
 673                 p_data->l_size = p_cache->large.p_stack[l_index].l_size;
 674             }
 675             }
 676     }
 677
 678     /* Initialize data */
 679     p_data->p_next = NULL;
 680     p_data->b_discard_payload = 0;
 681     p_data->p_payload_start = p_data->p_buffer;
 682     p_data->p_payload_end = p_data->p_buffer + l_size;
 683
 684     return( p_data );
 685
 686 }
 687
 688
 689 /*****************************************************************************
 690  * NewPES: allocates a pes packet
 691  *****************************************************************************/
 692 static pes_packet_t * NewPES( void * p_packet_cache )
 693 {
 694     packet_cache_t *   p_cache;
 695     pes_packet_t *     p_pes;
 696
 697     p_cache = (packet_cache_t *)p_packet_cache;
 698
 699 #ifdef DEBUG
 700     if ( p_cache == NULL )
 701     {
 702         intf_ErrMsg( "Packet cache not initialized" );
 703         return NULL;
 704     }
 705 #endif
 706
 707     /* Checks whether the PES cache is empty */
 708     if( p_cache->pes.l_index == 0 )
 709     {
 710         /* Allocates a new packet */
 711         if ( (p_pes = malloc( sizeof(pes_packet_t) )) == NULL )
 712         {
 713             intf_DbgMsg( "Out of memory" );
 714             return NULL;
 715         }
 716 #ifdef TRACE_INPUT
 717         intf_DbgMsg( "PS input: PES packet allocated" );
 718 #endif
 719     }
 720     else
 721     {
 722         /* Takes the packet out from the cache */
 723         if( (p_pes = p_cache->pes.p_stack[ -- p_cache->pes.l_index ])
 724             == NULL )
 725         {
 726             intf_ErrMsg( "NULL packet in the data cache" );
 727             return NULL;
 728         }
 729     }
 730
 731     p_pes->b_data_alignment = p_pes->b_discontinuity =
 732         p_pes->i_pts = p_pes->i_dts = 0;
 733     p_pes->i_pes_size = 0;
 734     p_pes->p_first = NULL;
 735
 736     return( p_pes );
 737
 738 }
 739
 740 /*****************************************************************************
 741  * DeletePacket: deletes a data packet
 742  *****************************************************************************/
 743 static void DeletePacket( void * p_packet_cache,
 744                           data_packet_t * p_data )
 745 {
 746     packet_cache_t *   p_cache;
 747
 748     p_cache = (packet_cache_t *)p_packet_cache;
 749
 750 #ifdef DEBUG
 751     if ( p_cache == NULL )
 752     {
 753         intf_ErrMsg( "Packet cache not initialized" );
 754         return;
 755     }
 756 #endif
 757
 758         ASSERT( p_data );
 759
 760     /* Checks whether the data cache is full */
 761     if ( p_cache->data.l_index < DATA_CACHE_SIZE )
 762     {
 763         /* Cache not full: store the packet in it */
 764         p_cache->data.p_stack[ p_cache->data.l_index ++ ] = p_data;
 765         /* Small buffer or large buffer? */
 766         if ( p_data->l_size < MAX_SMALL_SIZE )
 767         {
 768             /* Checks whether the small buffer cache is full */
 769             if ( p_cache->small.l_index < SMALL_CACHE_SIZE )
 770             {
 771                 p_cache->small.p_stack[ p_cache->small.l_index ].l_size =
 772                     p_data->l_size;
 773                 p_cache->small.p_stack[ p_cache->small.l_index ++ ].p_data =
 774                     p_data->p_buffer;
 775             }
 776             else
 777             {
 778                 ASSERT( p_data->p_buffer );
 779                 free( p_data->p_buffer );
 780 #ifdef TRACE_INPUT
 781                 intf_DbgMsg( "PS input: small buffer freed" );
 782 #endif
 783             }
 784         }
 785         else
 786         {
 787             /* Checks whether the large buffer cache is full */
 788             if ( p_cache->large.l_index < LARGE_CACHE_SIZE )
 789             {
 790                 p_cache->large.p_stack[ p_cache->large.l_index ].l_size =
 791                     p_data->l_size;
 792                 p_cache->large.p_stack[ p_cache->large.l_index ++ ].p_data =
 793                     p_data->p_buffer;
 794             }
 795             else
 796             {
 797                 ASSERT( p_data->p_buffer );
 798                 free( p_data->p_buffer );
 799 #ifdef TRACE_INPUT
 800                 intf_DbgMsg( "PS input: large buffer freed" );
 801 #endif
 802             }
 803         }
 804     }
 805     else
 806     {
 807         /* Cache full: the packet must be freed */
 808         free( p_data->p_buffer );
 809         free( p_data );
 810 #ifdef TRACE_INPUT
 811         intf_DbgMsg( "PS input: data packet freed" );
 812 #endif
 813     }
 814
 815 }
 816
 817 /*****************************************************************************
 818  * DeletePES: deletes a PES packet and associated data packets
 819  *****************************************************************************/
 820 static void DeletePES( void * p_packet_cache, pes_packet_t * p_pes )
 821 {
 822     packet_cache_t *    p_cache;
 823     data_packet_t *     p_data;
 824     data_packet_t *     p_next;
 825
 826     p_cache = (packet_cache_t *)p_packet_cache;
 827
 828 #ifdef DEBUG
 829     if ( p_cache == NULL )
 830     {
 831         intf_ErrMsg( "Packet cache not initialized" );
 832         return;
 833     }
 834 #endif
 835
 836     ASSERT( p_pes);
 837
 838     p_data = p_pes->p_first;
 839
 840     while( p_data != NULL )
 841     {
 842         p_next = p_data->p_next;
 843         DeletePacket( p_cache, p_data );
 844         p_data = p_next;
 845     }
 846
 847     /* Checks whether the PES cache is full */
 848     if ( p_cache->pes.l_index < PES_CACHE_SIZE )
 849     {
 850         /* Cache not full: store the packet in it */
 851         p_cache->pes.p_stack[ p_cache->pes.l_index ++ ] = p_pes;
 852     }
 853     else
 854     {
 855         /* Cache full: the packet must be freed */
 856         free( p_pes );
 857 #ifdef TRACE_INPUT
 858         intf_DbgMsg( "PS input: PES packet freed" );
 859 #endif
 860     }
 861 }
 862