modules/access/dv.c

   1 /*****************************************************************************
   2  * dv.c: Digital video/Firewire input (file: access plug-in)
   3  *****************************************************************************
   4  * Copyright (C) 2005 M2X
   5  * $Id$
   6  *
   7  * Authors: Jean-Paul Saman <jpsaman at m2x dot nl>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License along
  20  * with this program; if not, write to the Free Software Foundation, Inc.,
  21  * 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #ifdef HAVE_CONFIG_H
  28 # include "config.h"
  29 #endif
  30
  31 #include <vlc_common.h>
  32 #include <vlc_plugin.h>
  33 #include <vlc_access.h>
  34
  35 #include <errno.h>
  36 #include <sys/types.h>
  37 #ifdef HAVE_UNISTD_H
  38 #   include <unistd.h>
  39 #elif defined( WIN32 ) && !defined( UNDER_CE )
  40 #   include <io.h>
  41 #endif
  42
  43 #include <sys/poll.h>
  44
  45 #include <libraw1394/raw1394.h>
  46 #include <libraw1394/csr.h>
  47 #include <libavc1394/avc1394.h>
  48 #include <libavc1394/avc1394_vcr.h>
  49 #include <libavc1394/rom1394.h>
  50
  51 /*****************************************************************************
  52  * Module descriptor
  53  *****************************************************************************/
  54 static int  Open ( vlc_object_t * );
  55 static void Close( vlc_object_t * );
  56 static block_t *Block( access_t * );
  57 static int Control( access_t *, int, va_list );
  58
  59 #define CACHING_TEXT N_("Caching value in ms")
  60 #define CACHING_LONGTEXT N_( \
  61     "Caching value for DV streams. This " \
  62     "value should be set in milliseconds." )
  63
  64 vlc_module_begin ()
  65     set_description( N_("Digital Video (Firewire/ieee1394)  input") )
  66     set_shortname( N_("DV") )
  67     set_category( CAT_INPUT )
  68     set_subcategory( SUBCAT_INPUT_ACCESS )
  69     add_integer( "dv-caching", 60000 / 1000, CACHING_TEXT, CACHING_LONGTEXT, true )
  70         change_safe()
  71     set_capability( "access", 0 )
  72     add_shortcut( "dv", "dv1394", "raw1394" )
  73     set_callbacks( Open, Close )
  74 vlc_module_end ()
  75
  76 typedef struct
  77 {
  78     vlc_thread_t    thread;
  79     access_t        *p_access;
  80     vlc_mutex_t     lock;
  81     block_t         *p_frame;
  82     block_t         **pp_last;
  83
  84 } event_thread_t;
  85
  86 static void* Raw1394EventThread( void * );
  87 static enum raw1394_iso_disposition
  88 Raw1394Handler(raw1394handle_t, unsigned char *,
  89         unsigned int, unsigned char,
  90         unsigned char, unsigned char, unsigned int,
  91         unsigned int);
  92
  93 static int Raw1394GetNumPorts( access_t *p_access );
  94 static raw1394handle_t Raw1394Open( access_t *, int );
  95 static void Raw1394Close( raw1394handle_t );
  96
  97 static int DiscoverAVC( access_t *, int *, uint64_t );
  98 static raw1394handle_t AVCOpen( access_t *, int );
  99 static void AVCClose( access_t * );
 100 static int AVCResetHandler( raw1394handle_t, unsigned int );
 101 static int AVCPlay( access_t *, int );
 102 static int AVCPause( access_t *, int );
 103 static int AVCStop( access_t *, int );
 104
 105 struct access_sys_t
 106 {
 107     raw1394handle_t p_avc1394;
 108     raw1394handle_t p_raw1394;
 109     struct pollfd   raw1394_poll;
 110
 111     int i_cards;
 112     int i_node;
 113     int i_port;
 114     int i_channel;
 115     uint64_t i_guid;
 116
 117     /* event */
 118     event_thread_t *p_ev;
 119     vlc_mutex_t lock;
 120     block_t *p_frame;
 121 };
 122
 123 #define ISOCHRONOUS_QUEUE_LENGTH 1000
 124 #define ISOCHRONOUS_MAX_PACKET_SIZE 4096
 125
 126 /*****************************************************************************
 127  * Open: open the file
 128  *****************************************************************************/
 129 static int Open( vlc_object_t *p_this )
 130 {
 131     access_t     *p_access = (access_t*)p_this;
 132     access_sys_t *p_sys;
 133
 134     struct raw1394_portinfo port_inf[ 16 ];
 135
 136     msg_Dbg( p_access, "opening device" );
 137
 138     /* Set up p_access */
 139     access_InitFields( p_access );
 140     ACCESS_SET_CALLBACKS( NULL, Block, Control, NULL );
 141
 142     p_access->p_sys = p_sys = malloc( sizeof( access_sys_t ) );
 143     if( !p_sys )
 144         return VLC_EGENERIC;
 145
 146     p_sys->i_cards = 0;
 147     p_sys->i_node = 0;
 148     p_sys->i_port = 0;
 149     p_sys->i_guid = 0;
 150     p_sys->i_channel = 63;
 151     p_sys->p_raw1394 = NULL;
 152     p_sys->p_avc1394 = NULL;
 153     p_sys->p_frame = NULL;
 154     p_sys->p_ev = NULL;
 155
 156     vlc_mutex_init( &p_sys->lock );
 157
 158     p_sys->i_node = DiscoverAVC( p_access, &p_sys->i_port, p_sys->i_guid );
 159     if( p_sys->i_node < 0 )
 160     {
 161         msg_Err( p_access, "failed to open a Firewire (IEEE1394) connection" );
 162         Close( p_this );
 163         return VLC_EGENERIC;
 164     }
 165
 166     p_sys->p_avc1394 = AVCOpen( p_access, p_sys->i_port );
 167     if( !p_sys->p_avc1394 )
 168     {
 169         msg_Err( p_access, "no Digital Video Control device found" );
 170         Close( p_this );
 171         return VLC_EGENERIC;
 172     }
 173
 174     p_sys->p_raw1394 = raw1394_new_handle();
 175     if( !p_sys->p_raw1394 )
 176     {
 177         msg_Err( p_access, "no Digital Video device found" );
 178         Close( p_this );
 179         return VLC_EGENERIC;
 180     }
 181
 182     p_sys->i_cards = raw1394_get_port_info( p_sys->p_raw1394, port_inf, 16 );
 183     if( p_sys->i_cards < 0 )
 184     {
 185         msg_Err( p_access, "failed to get port info" );
 186         Close( p_this );
 187         return VLC_EGENERIC;
 188     }
 189
 190     if( raw1394_set_port( p_sys->p_raw1394, p_sys->i_port ) < 0 )
 191     {
 192         msg_Err( p_access, "failed to set port info" );
 193         Close( p_this );
 194         return VLC_EGENERIC;
 195     }
 196
 197     if ( raw1394_iso_recv_init( p_sys->p_raw1394, Raw1394Handler,
 198                 ISOCHRONOUS_QUEUE_LENGTH, ISOCHRONOUS_MAX_PACKET_SIZE,
 199                 p_sys->i_channel, RAW1394_DMA_PACKET_PER_BUFFER, -1 ) < 0 )
 200     {
 201         msg_Err( p_access, "failed to init isochronous recv" );
 202         Close( p_this );
 203         return VLC_EGENERIC;
 204     }
 205
 206     raw1394_set_userdata( p_sys->p_raw1394, p_access );
 207     raw1394_iso_recv_start( p_sys->p_raw1394, -1, -1, 0 );
 208
 209     p_sys->raw1394_poll.fd = raw1394_get_fd( p_sys->p_raw1394 );
 210     p_sys->raw1394_poll.events = POLLIN | POLLPRI;
 211
 212     /* Update default_pts to a suitable value for udp access */
 213     var_Create( p_access, "dv-caching", VLC_VAR_INTEGER | VLC_VAR_DOINHERIT );
 214
 215     /* Now create our event thread catcher */
 216     p_sys->p_ev = calloc( 1, sizeof( *p_sys->p_ev ) );
 217     if( !p_sys->p_ev )
 218     {
 219         msg_Err( p_access, "failed to create event thread" );
 220         Close( p_this );
 221         return VLC_EGENERIC;
 222     }
 223
 224     p_sys->p_ev->p_frame = NULL;
 225     p_sys->p_ev->pp_last = &p_sys->p_ev->p_frame;
 226     p_sys->p_ev->p_access = p_access;
 227     vlc_mutex_init( &p_sys->p_ev->lock );
 228     vlc_clone( &p_sys->p_ev->thread, Raw1394EventThread,
 229                p_sys->p_ev, VLC_THREAD_PRIORITY_OUTPUT );
 230
 231     return VLC_SUCCESS;
 232 }
 233
 234 /*****************************************************************************
 235  * Close: free unused data structures
 236  *****************************************************************************/
 237 static void Close( vlc_object_t *p_this )
 238 {
 239     access_t     *p_access = (access_t*)p_this;
 240     access_sys_t *p_sys = p_access->p_sys;
 241
 242     if( p_sys->p_ev )
 243     {
 244         /* stop the event handler */
 245         vlc_cancel( p_sys->p_ev->thread );
 246
 247         if( p_sys->p_raw1394 )
 248             raw1394_iso_shutdown( p_sys->p_raw1394 );
 249
 250         vlc_join( p_sys->p_ev->thread, NULL );
 251         vlc_mutex_destroy( &p_sys->p_ev->lock );
 252
 253         /* Cleanup frame data */
 254         if( p_sys->p_ev->p_frame )
 255         {
 256             block_ChainRelease( p_sys->p_ev->p_frame );
 257             p_sys->p_ev->p_frame = NULL;
 258             p_sys->p_ev->pp_last = &p_sys->p_frame;
 259         }
 260         free( p_sys->p_ev );
 261     }
 262
 263     if( p_sys->p_frame )
 264         block_ChainRelease( p_sys->p_frame );
 265     if( p_sys->p_raw1394 )
 266         raw1394_destroy_handle( p_sys->p_raw1394 );
 267
 268     AVCClose( p_access );
 269
 270     vlc_mutex_destroy( &p_sys->lock );
 271     free( p_sys );
 272 }
 273
 274 /*****************************************************************************
 275  * Control:
 276  *****************************************************************************/
 277 static int Control( access_t *p_access, int i_query, va_list args )
 278 {
 279     switch( i_query )
 280     {
 281         /* */
 282         case ACCESS_CAN_PAUSE:
 283             *va_arg( args, bool* ) = true;
 284             break;
 285
 286        case ACCESS_CAN_SEEK:
 287        case ACCESS_CAN_FASTSEEK:
 288        case ACCESS_CAN_CONTROL_PACE:
 289             *va_arg( args, bool* ) = false;
 290             break;
 291
 292         case ACCESS_GET_PTS_DELAY:
 293             *va_arg( args, int64_t * )
 294                    = var_GetInteger( p_access, "dv-caching" ) * 1000;
 295             break;
 296
 297         /* */
 298         case ACCESS_SET_PAUSE_STATE:
 299             AVCPause( p_access, p_access->p_sys->i_node );
 300             break;
 301
 302         case ACCESS_GET_TITLE_INFO:
 303         case ACCESS_SET_TITLE:
 304         case ACCESS_SET_SEEKPOINT:
 305         case ACCESS_SET_PRIVATE_ID_STATE:
 306         case ACCESS_GET_CONTENT_TYPE:
 307             return VLC_EGENERIC;
 308
 309         default:
 310             msg_Warn( p_access, "unimplemented query in control" );
 311             return VLC_EGENERIC;
 312
 313     }
 314     return VLC_SUCCESS;
 315 }
 316
 317 static block_t *Block( access_t *p_access )
 318 {
 319     access_sys_t *p_sys = p_access->p_sys;
 320     block_t *p_block = NULL;
 321
 322     vlc_mutex_lock( &p_sys->lock );
 323     p_block = p_sys->p_frame;
 324     //msg_Dbg( p_access, "sending frame %p",p_block );
 325     p_sys->p_frame = NULL;
 326     vlc_mutex_unlock( &p_sys->lock );
 327
 328     return p_block;
 329 }
 330
 331 static void Raw1394EventThreadCleanup( void *obj )
 332 {
 333     event_thread_t *p_ev = (event_thread_t *)obj;
 334
 335     AVCStop( p_ev->p_access, p_ev->p_access->p_sys->i_node );
 336 }
 337
 338 static void* Raw1394EventThread( void *obj )
 339 {
 340     event_thread_t *p_ev = (event_thread_t *)obj;
 341     access_t *p_access = (access_t *) p_ev->p_access;
 342     access_sys_t *p_sys = (access_sys_t *) p_access->p_sys;
 343     int result = 0;
 344     int canc = vlc_savecancel();
 345
 346     AVCPlay( p_access, p_sys->i_node );
 347     vlc_cleanup_push( Raw1394EventThreadCleanup, p_ev );
 348     vlc_restorecancel( canc );
 349
 350     for( ;; )
 351     {
 352         while( ( result = poll( &p_sys->raw1394_poll, 1, -1 ) ) < 0 )
 353         {
 354             if( errno != EINTR )
 355                 msg_Err( p_access, "poll error: %m" );
 356         }
 357
 358         if( result > 0 && ( ( p_sys->raw1394_poll.revents & POLLIN )
 359                          || ( p_sys->raw1394_poll.revents & POLLPRI ) ) )
 360         {
 361             canc = vlc_savecancel();
 362             result = raw1394_loop_iterate( p_sys->p_raw1394 );
 363             vlc_restorecancel( canc );
 364         }
 365     }
 366
 367     vlc_cleanup_run();
 368     return NULL;
 369 }
 370
 371 static enum raw1394_iso_disposition
 372 Raw1394Handler(raw1394handle_t handle, unsigned char *data,
 373         unsigned int length, unsigned char channel,
 374         unsigned char tag, unsigned char sy, unsigned int cycle,
 375         unsigned int dropped)
 376 {
 377     access_t *p_access = NULL;
 378     access_sys_t *p_sys = NULL;
 379     block_t *p_block = NULL;
 380     VLC_UNUSED(channel); VLC_UNUSED(tag);
 381     VLC_UNUSED(sy); VLC_UNUSED(cycle); VLC_UNUSED(dropped);
 382
 383     p_access = (access_t *) raw1394_get_userdata( handle );
 384     if( !p_access ) return 0;
 385
 386     p_sys = p_access->p_sys;
 387
 388     /* skip empty packets */
 389     if( length > 16 )
 390     {
 391         unsigned char * p = data + 8;
 392         int section_type = p[ 0 ] >> 5;           /* section type is in bits 5 - 7 */
 393         int dif_sequence = p[ 1 ] >> 4;           /* dif sequence number is in bits 4 - 7 */
 394         int dif_block = p[ 2 ];
 395
 396         vlc_mutex_lock( &p_sys->p_ev->lock );
 397
 398         /* if we are at the beginning of a frame, we put the previous
 399            frame in our output_queue. */
 400         if( (section_type == 0) && (dif_sequence == 0) )
 401         {
 402             vlc_mutex_lock( &p_sys->lock );
 403             if( p_sys->p_ev->p_frame )
 404             {
 405                 /* Push current frame to p_access thread. */
 406                 //p_sys->p_ev->p_frame->i_pts = mdate();
 407                 block_ChainAppend( &p_sys->p_frame, p_sys->p_ev->p_frame );
 408             }
 409             /* reset list */
 410             p_sys->p_ev->p_frame = block_New( p_access, 144000 );
 411             p_sys->p_ev->pp_last = &p_sys->p_frame;
 412             vlc_mutex_unlock( &p_sys->lock );
 413         }
 414
 415         p_block = p_sys->p_ev->p_frame;
 416         if( p_block )
 417         {
 418             switch ( section_type )
 419             {
 420             case 0:    /* 1 Header block */
 421                 /* p[3] |= 0x80; // hack to force PAL data */
 422                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80, p, 480 );
 423                 break;
 424
 425             case 1:    /* 2 Subcode blocks */
 426                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 1 + dif_block ) * 80, p, 480 );
 427                 break;
 428
 429             case 2:    /* 3 VAUX blocks */
 430                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 3 + dif_block ) * 80, p, 480 );
 431                 break;
 432
 433             case 3:    /* 9 Audio blocks interleaved with video */
 434                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 6 + dif_block * 16 ) * 80, p, 480 );
 435                 break;
 436
 437             case 4:    /* 135 Video blocks interleaved with audio */
 438                 memcpy( p_block->p_buffer + dif_sequence * 150 * 80 + ( 7 + ( dif_block / 15 ) + dif_block ) * 80, p, 480 );
 439                 break;
 440
 441             default:    /* we can´t handle any other data */
 442                 block_Release( p_block );
 443                 p_block = NULL;
 444                 break;
 445             }
 446         }
 447
 448         vlc_mutex_unlock( &p_sys->p_ev->lock );
 449     }
 450     return 0;
 451 }
 452
 453 /*
 454  * Routing borrowed from dvgrab-1.8
 455  * Copyright by Arne Schirmacher <dvgrab@schirmacher.de>
 456  * Dan Dennedy <dan@dennedy.org> and others
 457  */
 458 static int Raw1394GetNumPorts( access_t *p_access )
 459 {
 460     int n_ports;
 461     struct raw1394_portinfo pinf[ 16 ];
 462     raw1394handle_t handle;
 463
 464     /* get a raw1394 handle */
 465     if( !( handle = raw1394_new_handle() ) )
 466     {
 467         msg_Err( p_access, "raw1394 - failed to get handle: %m." );
 468         return VLC_EGENERIC;
 469     }
 470
 471     if( ( n_ports = raw1394_get_port_info( handle, pinf, 16 ) ) < 0 )
 472     {
 473         msg_Err( p_access, "raw1394 - failed to get port info: %m." );
 474         raw1394_destroy_handle( handle );
 475         return VLC_EGENERIC;
 476     }
 477     raw1394_destroy_handle( handle );
 478
 479     return n_ports;
 480 }
 481
 482 static raw1394handle_t Raw1394Open( access_t *p_access, int port )
 483 {
 484     int n_ports;
 485     struct raw1394_portinfo pinf[ 16 ];
 486     raw1394handle_t handle;
 487
 488     /* get a raw1394 handle */
 489     handle = raw1394_new_handle();
 490     if( !handle )
 491     {
 492         msg_Err( p_access, "raw1394 - failed to get handle: %m." );
 493         return NULL;
 494     }
 495
 496     if( ( n_ports = raw1394_get_port_info( handle, pinf, 16 ) ) < 0 )
 497     {
 498         msg_Err( p_access, "raw1394 - failed to get port info: %m." );
 499         raw1394_destroy_handle( handle );
 500         return NULL;
 501     }
 502
 503     /* tell raw1394 which host adapter to use */
 504     if( raw1394_set_port( handle, port ) < 0 )
 505     {
 506         msg_Err( p_access, "raw1394 - failed to set set port: %m." );
 507         return NULL;
 508     }
 509
 510     return handle;
 511 }
 512
 513 static void Raw1394Close( raw1394handle_t handle )
 514 {
 515     raw1394_destroy_handle( handle );
 516 }
 517
 518 static int DiscoverAVC( access_t *p_access, int* port, uint64_t guid )
 519 {
 520     rom1394_directory rom_dir;
 521     raw1394handle_t handle = NULL;
 522     int device = -1;
 523     int i, j = 0;
 524     int m = Raw1394GetNumPorts( p_access );
 525
 526     if( *port >= 0 )
 527     {
 528         /* search on explicit port */
 529         j = *port;
 530         m = *port + 1;
 531     }
 532
 533     for( ; j < m && device == -1; j++ )
 534     {
 535         handle = Raw1394Open( p_access, j );
 536         if( !handle )
 537             return -1;
 538
 539         for( i = 0; i < raw1394_get_nodecount( handle ); ++i )
 540         {
 541             if( guid != 0 )
 542             {
 543                 /* select explicitly by GUID */
 544                 if( guid == rom1394_get_guid( handle, i ) )
 545                 {
 546                     device = i;
 547                     *port = j;
 548                     break;
 549                 }
 550             }
 551             else
 552             {
 553                 /* select first AV/C Tape Reccorder Player node */
 554                 if( rom1394_get_directory( handle, i, &rom_dir ) < 0 )
 555                 {
 556                     msg_Err( p_access, "error reading config rom directory for node %d", i );
 557                     continue;
 558                 }
 559                 if( ( rom1394_get_node_type( &rom_dir ) == ROM1394_NODE_TYPE_AVC ) &&
 560                         avc1394_check_subunit_type( handle, i, AVC1394_SUBUNIT_TYPE_VCR ) )
 561                 {
 562                     device = i;
 563                     *port = j;
 564                     break;
 565                 }
 566             }
 567         }
 568         Raw1394Close( handle );
 569     }
 570
 571     return device;
 572 }
 573
 574 /*
 575  * Handle AVC commands
 576  */
 577 static raw1394handle_t AVCOpen( access_t *p_access, int port )
 578 {
 579     access_sys_t *p_sys = p_access->p_sys;
 580     struct raw1394_portinfo pinf[ 16 ];
 581     int numcards;
 582
 583     p_sys->p_avc1394 = raw1394_new_handle();
 584     if( !p_sys->p_avc1394 )
 585         return NULL;
 586
 587     numcards = raw1394_get_port_info( p_sys->p_avc1394, pinf, 16 );
 588     if( numcards < -1 )
 589         return NULL;
 590     if( raw1394_set_port( p_sys->p_avc1394, port ) < 0 )
 591         return NULL;
 592
 593     raw1394_set_bus_reset_handler( p_sys->p_avc1394, AVCResetHandler );
 594
 595     return  p_sys->p_avc1394;
 596 }
 597
 598 static void AVCClose( access_t *p_access )
 599 {
 600     access_sys_t *p_sys = p_access->p_sys;
 601
 602     if( p_sys->p_avc1394 )
 603     {
 604         raw1394_destroy_handle( p_sys->p_avc1394 );
 605         p_sys->p_avc1394 = NULL;
 606     }
 607 }
 608
 609 static int AVCResetHandler( raw1394handle_t handle, unsigned int generation )
 610 {
 611     raw1394_update_generation( handle, generation );
 612     return 0;
 613 }
 614
 615 static int AVCPlay( access_t *p_access, int phyID )
 616 {
 617     access_sys_t *p_sys = p_access->p_sys;
 618
 619     msg_Dbg( p_access, "send play command over Digital Video control channel" );
 620
 621     if( p_sys->p_avc1394 && phyID >= 0 )
 622     {
 623         if( !avc1394_vcr_is_recording( p_sys->p_avc1394, phyID ) &&
 624             avc1394_vcr_is_playing( p_sys->p_avc1394, phyID ) != AVC1394_VCR_OPERAND_PLAY_FORWARD )
 625                 avc1394_vcr_play( p_sys->p_avc1394, phyID );
 626     }
 627     return 0;
 628 }
 629
 630 static int AVCPause( access_t *p_access, int phyID )
 631 {
 632     access_sys_t *p_sys = p_access->p_sys;
 633
 634     if( p_sys->p_avc1394 && phyID >= 0 )
 635     {
 636         if( !avc1394_vcr_is_recording( p_sys->p_avc1394, phyID ) &&
 637             ( avc1394_vcr_is_playing( p_sys->p_avc1394, phyID ) != AVC1394_VCR_OPERAND_PLAY_FORWARD_PAUSE ) )
 638                 avc1394_vcr_pause( p_sys->p_avc1394, phyID );
 639     }
 640     return 0;
 641 }
 642
 643
 644 static int AVCStop( access_t *p_access, int phyID )
 645 {
 646     access_sys_t *p_sys = p_access->p_sys;
 647
 648     msg_Dbg( p_access, "closing Digital Video control channel" );
 649
 650     if ( p_sys->p_avc1394 && phyID >= 0 )
 651         avc1394_vcr_stop( p_sys->p_avc1394, phyID );
 652
 653     return 0;
 654 }