git.sesse.net Git - vlc/blob - modules/audio_output/directx.c

   1 /*****************************************************************************
   2  * directx.c: Windows DirectX audio output method
   3  *****************************************************************************
   4  * Copyright (C) 2001 VideoLAN
   5  * $Id: directx.c,v 1.10 2003/01/05 13:39:32 gbazin Exp $
   6  *
   7  * Authors: Gildas Bazin <gbazin@netcourrier.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111, USA.
  22  *****************************************************************************/
  23
  24 /*****************************************************************************
  25  * Preamble
  26  *****************************************************************************/
  27 #include <errno.h>                                                 /* ENOMEM */
  28 #include <fcntl.h>                                       /* open(), O_WRONLY */
  29 #include <string.h>                                            /* strerror() */
  30
  31 #include <stdlib.h>                            /* calloc(), malloc(), free() */
  32
  33 #include <vlc/vlc.h>
  34 #include <vlc/aout.h>
  35 #include "aout_internal.h"
  36
  37 #include <windows.h>
  38 #include <mmsystem.h>
  39 #include <dsound.h>
  40
  41 #define FRAME_SIZE 2048              /* The size is in samples, not in bytes */
  42 #define FRAMES_NUM 4
  43
  44 /* frame buffer status */
  45 #define FRAME_QUEUED 0
  46 #define FRAME_EMPTY 1
  47
  48 /*****************************************************************************
  49  * DirectSound GUIDs.
  50  * Defining them here allows us to get rid of the dxguid library during
  51  * the linking stage.
  52  *****************************************************************************/
  53 #include <initguid.h>
  54 DEFINE_GUID(IID_IDirectSoundNotify, 0xb0210783, 0x89cd, 0x11d0, 0xaf, 0x8, 0x0, 0xa0, 0xc9, 0x25, 0xcd, 0x16);
  55
  56 /*****************************************************************************
  57  * Useful macros
  58  *****************************************************************************/
  59 #ifndef WAVE_FORMAT_IEEE_FLOAT
  60 #   define WAVE_FORMAT_IEEE_FLOAT 0x0003
  61 #endif
  62
  63 /*****************************************************************************
  64  * notification_thread_t: DirectX event thread
  65  *****************************************************************************/
  66 typedef struct notification_thread_t
  67 {
  68     VLC_COMMON_MEMBERS
  69
  70     aout_instance_t * p_aout;
  71     int i_frame_status[FRAMES_NUM];           /* status of each frame buffer */
  72     DSBPOSITIONNOTIFY p_events[FRAMES_NUM];      /* play notification events */
  73     int i_frame_size;                         /* Size in bytes of one frame */
  74
  75     mtime_t start_date;
  76
  77 } notification_thread_t;
  78
  79 /*****************************************************************************
  80  * aout_sys_t: directx audio output method descriptor
  81  *****************************************************************************
  82  * This structure is part of the audio output thread descriptor.
  83  * It describes the direct sound specific properties of an audio device.
  84  *****************************************************************************/
  85 struct aout_sys_t
  86 {
  87     LPDIRECTSOUND       p_dsobject;              /* main Direct Sound object */
  88
  89     LPDIRECTSOUNDBUFFER p_dsbuffer;   /* the sound buffer we use (direct sound
  90                                        * takes care of mixing all the
  91                                        * secondary buffers into the primary) */
  92
  93     LPDIRECTSOUNDNOTIFY p_dsnotify;         /* the position notify interface */
  94
  95     HINSTANCE           hdsound_dll;      /* handle of the opened dsound dll */
  96
  97     notification_thread_t * p_notif;                 /* DirectSoundThread id */
  98
  99     int b_playing;                                         /* playing status */
 100 };
 101
 102 /*****************************************************************************
 103  * Local prototypes.
 104  *****************************************************************************/
 105 static int  OpenAudio  ( vlc_object_t * );
 106 static void CloseAudio ( vlc_object_t * );
 107
 108 static void Play       ( aout_instance_t * );
 109
 110 /* local functions */
 111 static int  DirectxCreateSecondaryBuffer ( aout_instance_t * );
 112 static void DirectxDestroySecondaryBuffer( aout_instance_t * );
 113 static int  DirectxInitDSound            ( aout_instance_t * );
 114 static void DirectSoundThread            ( notification_thread_t * );
 115 static int  DirectxFillBuffer            ( aout_instance_t *, int,
 116                                            aout_buffer_t * );
 117
 118 /*****************************************************************************
 119  * Module descriptor
 120  *****************************************************************************/
 121 vlc_module_begin();
 122     set_description( _("DirectX audio module") );
 123     set_capability( "audio output", 100 );
 124     add_shortcut( "directx" );
 125     set_callbacks( OpenAudio, CloseAudio );
 126 vlc_module_end();
 127
 128 /*****************************************************************************
 129  * OpenAudio: open the audio device
 130  *****************************************************************************
 131  * This function opens and setups Direct Sound.
 132  *****************************************************************************/
 133 static int OpenAudio( vlc_object_t *p_this )
 134 {
 135     aout_instance_t * p_aout = (aout_instance_t *)p_this;
 136     int i;
 137
 138     msg_Dbg( p_aout, "Open" );
 139
 140    /* Allocate structure */
 141     p_aout->output.p_sys = malloc( sizeof( aout_sys_t ) );
 142     if( p_aout->output.p_sys == NULL )
 143     {
 144         msg_Err( p_aout, "out of memory" );
 145         return VLC_EGENERIC;
 146     }
 147
 148     /* Initialize some variables */
 149     p_aout->output.p_sys->p_dsobject = NULL;
 150     p_aout->output.p_sys->p_dsbuffer = NULL;
 151     p_aout->output.p_sys->p_dsnotify = NULL;
 152     p_aout->output.p_sys->p_notif = NULL;
 153     p_aout->output.p_sys->b_playing = 0;
 154
 155     p_aout->output.pf_play = Play;
 156     aout_VolumeSoftInit( p_aout );
 157
 158     /* Initialise DirectSound */
 159     if( DirectxInitDSound( p_aout ) )
 160     {
 161         msg_Err( p_aout, "cannot initialize DirectSound" );
 162         goto error;
 163     }
 164
 165     /* Now we need to setup DirectSound play notification */
 166     p_aout->output.p_sys->p_notif =
 167         vlc_object_create( p_aout, sizeof(notification_thread_t) );
 168     p_aout->output.p_sys->p_notif->p_aout = p_aout;
 169
 170     /* first we need to create the notification events */
 171     for( i = 0; i < FRAMES_NUM; i++ )
 172         p_aout->output.p_sys->p_notif->p_events[i].hEventNotify =
 173             CreateEvent( NULL, FALSE, FALSE, NULL );
 174
 175     /* then create a new secondary buffer */
 176     p_aout->output.output.i_format = VLC_FOURCC('f','l','3','2');
 177     if( DirectxCreateSecondaryBuffer( p_aout ) )
 178     {
 179         msg_Dbg( p_aout, "cannot create WAVE_FORMAT_IEEE_FLOAT buffer" );
 180
 181         p_aout->output.output.i_format = VLC_FOURCC('s','1','6','l');
 182         if( DirectxCreateSecondaryBuffer( p_aout ) )
 183         {
 184             msg_Err( p_aout, "cannot create WAVE_FORMAT_PCM buffer" );
 185             return 1;
 186         }
 187     }
 188
 189     /* then launch the notification thread */
 190     msg_Dbg( p_aout, "creating DirectSoundThread" );
 191     if( vlc_thread_create( p_aout->output.p_sys->p_notif,
 192                            "DirectSound Notification Thread",
 193                            DirectSoundThread,
 194                            VLC_THREAD_PRIORITY_HIGHEST, 1 ) )
 195     {
 196         msg_Err( p_aout, "cannot create DirectSoundThread" );
 197         goto error;
 198     }
 199
 200     vlc_object_attach( p_aout->output.p_sys->p_notif, p_aout );
 201
 202     return 0;
 203
 204  error:
 205     CloseAudio( VLC_OBJECT(p_aout) );
 206     return VLC_EGENERIC;
 207 }
 208
 209 /*****************************************************************************
 210  * Play: we'll start playing the directsound buffer here because at least here
 211  *       we know the first buffer has been put in the aout fifo and we also
 212  *       know its date.
 213  *****************************************************************************/
 214 static void Play( aout_instance_t *p_aout )
 215 {
 216     if( !p_aout->output.p_sys->b_playing )
 217     {
 218         aout_buffer_t *p_buffer;
 219
 220         p_aout->output.p_sys->b_playing = 1;
 221
 222         /* get the playing date of the first aout buffer */
 223         p_aout->output.p_sys->p_notif->start_date =
 224             aout_FifoFirstDate( p_aout, &p_aout->output.fifo );
 225
 226         /* fill in the first samples */
 227         p_buffer = aout_FifoPop( p_aout, &p_aout->output.fifo );
 228         DirectxFillBuffer( p_aout, 0, p_buffer );
 229
 230         /* wake up the audio output thread */
 231         SetEvent( p_aout->output.p_sys->p_notif->p_events[0].hEventNotify );
 232     }
 233 }
 234
 235 /*****************************************************************************
 236  * CloseAudio: close the audio device
 237  *****************************************************************************/
 238 static void CloseAudio( vlc_object_t *p_this )
 239 {
 240     aout_instance_t * p_aout = (aout_instance_t *)p_this;
 241
 242     msg_Dbg( p_aout, "Close" );
 243
 244     /* kill the position notification thread, if any */
 245     if( p_aout->output.p_sys->p_notif )
 246     {
 247         vlc_object_detach( p_aout->output.p_sys->p_notif );
 248         if( p_aout->output.p_sys->p_notif->b_thread )
 249         {
 250             p_aout->output.p_sys->p_notif->b_die = 1;
 251
 252             if( !p_aout->output.p_sys->b_playing )
 253                 /* wake up the audio thread */
 254                 SetEvent(
 255                     p_aout->output.p_sys->p_notif->p_events[0].hEventNotify );
 256
 257             vlc_thread_join( p_aout->output.p_sys->p_notif );
 258         }
 259         vlc_object_destroy( p_aout->output.p_sys->p_notif );
 260     }
 261
 262     /* release the secondary buffer */
 263     DirectxDestroySecondaryBuffer( p_aout );
 264
 265     /* finally release the DirectSound object */
 266     if( p_aout->output.p_sys->p_dsobject )
 267         IDirectSound_Release( p_aout->output.p_sys->p_dsobject );
 268
 269     /* free DSOUND.DLL */
 270     if( p_aout->output.p_sys->hdsound_dll )
 271        FreeLibrary( p_aout->output.p_sys->hdsound_dll );
 272
 273     free( p_aout->output.p_sys );
 274 }
 275
 276 /*****************************************************************************
 277  * DirectxInitDSound: handle all the gory details of DirectSound initialisation
 278  *****************************************************************************/
 279 static int DirectxInitDSound( aout_instance_t *p_aout )
 280 {
 281     HRESULT (WINAPI *OurDirectSoundCreate)(LPGUID, LPDIRECTSOUND *, LPUNKNOWN);
 282
 283     p_aout->output.p_sys->hdsound_dll = LoadLibrary("DSOUND.DLL");
 284     if( p_aout->output.p_sys->hdsound_dll == NULL )
 285     {
 286         msg_Warn( p_aout, "cannot open DSOUND.DLL" );
 287         goto error;
 288     }
 289
 290     OurDirectSoundCreate = (void *)GetProcAddress(
 291                                            p_aout->output.p_sys->hdsound_dll,
 292                                            "DirectSoundCreate" );
 293     if( OurDirectSoundCreate == NULL )
 294     {
 295         msg_Warn( p_aout, "GetProcAddress FAILED" );
 296         goto error;
 297     }
 298
 299     /* Create the direct sound object */
 300     if( OurDirectSoundCreate( NULL, &p_aout->output.p_sys->p_dsobject, NULL )
 301         != DS_OK )
 302     {
 303         msg_Warn( p_aout, "cannot create a direct sound device" );
 304         goto error;
 305     }
 306
 307     /* Set DirectSound Cooperative level, ie what control we want over Windows
 308      * sound device. In our case, DSSCL_EXCLUSIVE means that we can modify the
 309      * settings of the primary buffer, but also that only the sound of our
 310      * application will be hearable when it will have the focus.
 311      * !!! (this is not really working as intended yet because to set the
 312      * cooperative level you need the window handle of your application, and
 313      * I don't know of any easy way to get it. Especially since we might play
 314      * sound without any video, and so what window handle should we use ???
 315      * The hack for now is to use the Desktop window handle - it seems to be
 316      * working */
 317     if( IDirectSound_SetCooperativeLevel( p_aout->output.p_sys->p_dsobject,
 318                                           GetDesktopWindow(),
 319                                           DSSCL_EXCLUSIVE) )
 320     {
 321         msg_Warn( p_aout, "cannot set direct sound cooperative level" );
 322     }
 323
 324     return 0;
 325
 326  error:
 327     p_aout->output.p_sys->p_dsobject = NULL;
 328     if( p_aout->output.p_sys->hdsound_dll )
 329     {
 330         FreeLibrary( p_aout->output.p_sys->hdsound_dll );
 331         p_aout->output.p_sys->hdsound_dll = NULL;
 332     }
 333     return 1;
 334
 335 }
 336
 337 /*****************************************************************************
 338  * DirectxCreateSecondaryBuffer
 339  *****************************************************************************
 340  * This function creates the buffer we'll use to play audio.
 341  * In DirectSound there are two kinds of buffers:
 342  * - the primary buffer: which is the actual buffer that the soundcard plays
 343  * - the secondary buffer(s): these buffers are the one actually used by
 344  *    applications and DirectSound takes care of mixing them into the primary.
 345  *
 346  * Once you create a secondary buffer, you cannot change its format anymore so
 347  * you have to release the current and create another one.
 348  *****************************************************************************/
 349 static int DirectxCreateSecondaryBuffer( aout_instance_t *p_aout )
 350 {
 351     WAVEFORMATEX         waveformat;
 352     DSBUFFERDESC         dsbdesc;
 353     DSBCAPS              dsbcaps;
 354     int                  i_nb_channels, i;
 355
 356     i_nb_channels = aout_FormatNbChannels( &p_aout->output.output );
 357     if ( i_nb_channels >= 2 )
 358     {
 359         i_nb_channels = 2;
 360         p_aout->output.output.i_physical_channels =
 361             AOUT_CHAN_LEFT | AOUT_CHAN_RIGHT;
 362     }
 363     else
 364     {
 365         i_nb_channels = 1;
 366         p_aout->output.output.i_physical_channels =
 367             AOUT_CHAN_CENTER;
 368     }
 369
 370     /* First set the buffer format */
 371     memset( &waveformat, 0, sizeof(WAVEFORMATEX) );
 372     switch( p_aout->output.output.i_format )
 373     {
 374     case VLC_FOURCC('s','1','6','l'):
 375         waveformat.wFormatTag     = WAVE_FORMAT_PCM;
 376         waveformat.wBitsPerSample = 16;
 377         break;
 378     case VLC_FOURCC('f','l','3','2'):
 379         waveformat.wFormatTag     = WAVE_FORMAT_IEEE_FLOAT;
 380         waveformat.wBitsPerSample = sizeof(float) * 8;
 381         break;
 382     }
 383     waveformat.nChannels       = i_nb_channels;
 384     waveformat.nSamplesPerSec  = p_aout->output.output.i_rate;
 385     waveformat.nBlockAlign     = waveformat.wBitsPerSample / 8 *
 386                                  waveformat.nChannels;
 387     waveformat.nAvgBytesPerSec = waveformat.nSamplesPerSec *
 388                                      waveformat.nBlockAlign;
 389
 390     aout_FormatPrepare( &p_aout->output.output );
 391
 392     /* Then fill in the descriptor */
 393     memset(&dsbdesc, 0, sizeof(DSBUFFERDESC));
 394     dsbdesc.dwSize = sizeof(DSBUFFERDESC);
 395     dsbdesc.dwFlags = DSBCAPS_GETCURRENTPOSITION2/* Better position accuracy */
 396                     | DSBCAPS_CTRLPOSITIONNOTIFY     /* We need notification */
 397                     | DSBCAPS_GLOBALFOCUS;      /* Allows background playing */
 398     dsbdesc.dwBufferBytes = FRAME_SIZE * FRAMES_NUM           /* buffer size */
 399                             * p_aout->output.output.i_bytes_per_frame;
 400     dsbdesc.lpwfxFormat = &waveformat;
 401
 402     if( IDirectSound_CreateSoundBuffer( p_aout->output.p_sys->p_dsobject,
 403                                         &dsbdesc,
 404                                         &p_aout->output.p_sys->p_dsbuffer,
 405                                         NULL) != DS_OK )
 406     {
 407         msg_Warn( p_aout, "cannot create direct sound secondary buffer" );
 408         goto error;
 409     }
 410
 411     /* backup the size of a frame */
 412     p_aout->output.p_sys->p_notif->i_frame_size = FRAME_SIZE *
 413         p_aout->output.output.i_bytes_per_frame;
 414
 415     memset(&dsbcaps, 0, sizeof(DSBCAPS));
 416     dsbcaps.dwSize = sizeof(DSBCAPS);
 417     IDirectSoundBuffer_GetCaps( p_aout->output.p_sys->p_dsbuffer, &dsbcaps  );
 418     msg_Dbg( p_aout, "requested %li bytes buffer and got %li bytes.",
 419              FRAMES_NUM * p_aout->output.p_sys->p_notif->i_frame_size,
 420              dsbcaps.dwBufferBytes );
 421
 422     /* Now the secondary buffer is created, we need to setup its position
 423      * notification */
 424     for( i = 0; i < FRAMES_NUM; i++ )
 425     {
 426         p_aout->output.p_sys->p_notif->p_events[i].dwOffset = i *
 427             p_aout->output.p_sys->p_notif->i_frame_size;
 428
 429         p_aout->output.p_sys->p_notif->i_frame_status[i] = FRAME_EMPTY;
 430     }
 431
 432     /* Get the IDirectSoundNotify interface */
 433     if FAILED( IDirectSoundBuffer_QueryInterface(
 434                                 p_aout->output.p_sys->p_dsbuffer,
 435                                 &IID_IDirectSoundNotify,
 436                                 (LPVOID *)&p_aout->output.p_sys->p_dsnotify ) )
 437     {
 438         msg_Err( p_aout, "cannot get Notify interface" );
 439         goto error;
 440     }
 441
 442     if FAILED( IDirectSoundNotify_SetNotificationPositions(
 443                                     p_aout->output.p_sys->p_dsnotify,
 444                                     FRAMES_NUM,
 445                                     p_aout->output.p_sys->p_notif->p_events ) )
 446     {
 447         msg_Err( p_aout, "cannot set position Notification" );
 448         goto error;
 449     }
 450
 451     p_aout->output.i_nb_samples = FRAME_SIZE;
 452
 453     return 0;
 454
 455  error:
 456     if( p_aout->output.p_sys->p_dsbuffer )
 457     {
 458         IDirectSoundBuffer_Release( p_aout->output.p_sys->p_dsbuffer );
 459         p_aout->output.p_sys->p_dsbuffer = NULL;
 460     }
 461     if( p_aout->output.p_sys->p_dsnotify )
 462     {
 463         IDirectSoundBuffer_Release( p_aout->output.p_sys->p_dsbuffer );
 464         p_aout->output.p_sys->p_dsnotify = NULL;
 465     }
 466     return VLC_EGENERIC;
 467 }
 468
 469 /*****************************************************************************
 470  * DirectxCreateSecondaryBuffer
 471  *****************************************************************************
 472  * This function destroys the secondary buffer.
 473  *****************************************************************************/
 474 static void DirectxDestroySecondaryBuffer( aout_instance_t *p_aout )
 475 {
 476     /* make sure the buffer isn't playing */
 477     if( p_aout->output.p_sys->p_dsbuffer )
 478         IDirectSoundBuffer_Stop( p_aout->output.p_sys->p_dsbuffer );
 479
 480     if( p_aout->output.p_sys->p_dsnotify )
 481     {
 482         IDirectSoundNotify_Release( p_aout->output.p_sys->p_dsnotify );
 483         p_aout->output.p_sys->p_dsnotify = NULL;
 484     }
 485
 486     if( p_aout->output.p_sys->p_dsbuffer )
 487     {
 488         IDirectSoundBuffer_Release( p_aout->output.p_sys->p_dsbuffer );
 489         p_aout->output.p_sys->p_dsbuffer = NULL;
 490     }
 491 }
 492
 493 /*****************************************************************************
 494  * DirectxFillBuffer: Fill in one of the direct sound frame buffers.
 495  *****************************************************************************
 496  * Returns VLC_SUCCESS on success.
 497  *****************************************************************************/
 498 static int DirectxFillBuffer( aout_instance_t *p_aout, int i_frame,
 499                               aout_buffer_t *p_buffer )
 500 {
 501     notification_thread_t *p_notif = p_aout->output.p_sys->p_notif;
 502     void *p_write_position, *p_wrap_around;
 503     long l_bytes1, l_bytes2;
 504     HRESULT dsresult;
 505
 506     /* Before copying anything, we have to lock the buffer */
 507     dsresult = IDirectSoundBuffer_Lock(
 508                 p_aout->output.p_sys->p_dsbuffer,               /* DS buffer */
 509                 i_frame * p_notif->i_frame_size,             /* Start offset */
 510                 p_notif->i_frame_size,                    /* Number of bytes */
 511                 &p_write_position,                  /* Address of lock start */
 512                 &l_bytes1,       /* Count of bytes locked before wrap around */
 513                 &p_wrap_around,            /* Buffer adress (if wrap around) */
 514                 &l_bytes2,               /* Count of bytes after wrap around */
 515                 0 );                                                /* Flags */
 516     if( dsresult == DSERR_BUFFERLOST )
 517     {
 518         IDirectSoundBuffer_Restore( p_aout->output.p_sys->p_dsbuffer );
 519         dsresult = IDirectSoundBuffer_Lock(
 520                                p_aout->output.p_sys->p_dsbuffer,
 521                                i_frame * p_notif->i_frame_size,
 522                                p_notif->i_frame_size,
 523                                &p_write_position,
 524                                &l_bytes1,
 525                                &p_wrap_around,
 526                                &l_bytes2,
 527                                0 );
 528     }
 529     if( dsresult != DS_OK )
 530     {
 531         msg_Warn( p_notif, "cannot lock buffer" );
 532         if( p_buffer ) aout_BufferFree( p_buffer );
 533         return VLC_EGENERIC;
 534     }
 535
 536     if ( p_buffer != NULL )
 537     {
 538         p_aout->p_vlc->pf_memcpy( p_write_position, p_buffer->p_buffer,
 539                                   l_bytes1 );
 540         aout_BufferFree( p_buffer );
 541     }
 542     else
 543         memset( p_write_position, 0, l_bytes1 );
 544
 545     /* Now the data has been copied, unlock the buffer */
 546     IDirectSoundBuffer_Unlock( p_aout->output.p_sys->p_dsbuffer,
 547                                p_write_position, l_bytes1,
 548                                p_wrap_around, l_bytes2 );
 549
 550     return VLC_SUCCESS;
 551 }
 552
 553 /*****************************************************************************
 554  * DirectSoundThread: this thread will capture play notification events.
 555  *****************************************************************************
 556  * We use this thread to emulate a callback mechanism. The thread probes for
 557  * event notification and fills up the DS secondary buffer when needed.
 558  *****************************************************************************/
 559 static void DirectSoundThread( notification_thread_t *p_notif )
 560 {
 561     HANDLE  notification_events[FRAMES_NUM];
 562     HRESULT dsresult;
 563     aout_instance_t *p_aout = p_notif->p_aout;
 564     int i, i_which_frame, i_last_frame, i_next_frame;
 565     mtime_t mtime;
 566
 567     for( i = 0; i < FRAMES_NUM; i++ )
 568         notification_events[i] = p_notif->p_events[i].hEventNotify;
 569
 570     /* Tell the main thread that we are ready */
 571     vlc_thread_ready( p_notif );
 572
 573     msg_Dbg( p_notif, "DirectSoundThread ready" );
 574
 575     /* Wait here until Play() is called */
 576     WaitForSingleObject( notification_events[0], INFINITE );
 577
 578     if( !p_notif->b_die )
 579     {
 580         mwait( p_notif->start_date - AOUT_PTS_TOLERANCE / 2 );
 581
 582         /* start playing the buffer */
 583         dsresult = IDirectSoundBuffer_Play( p_aout->output.p_sys->p_dsbuffer,
 584                                         0,                         /* Unused */
 585                                         0,                         /* Unused */
 586                                         DSBPLAY_LOOPING );          /* Flags */
 587         if( dsresult == DSERR_BUFFERLOST )
 588         {
 589             IDirectSoundBuffer_Restore( p_aout->output.p_sys->p_dsbuffer );
 590             dsresult = IDirectSoundBuffer_Play(
 591                                             p_aout->output.p_sys->p_dsbuffer,
 592                                             0,                     /* Unused */
 593                                             0,                     /* Unused */
 594                                             DSBPLAY_LOOPING );      /* Flags */
 595         }
 596         if( dsresult != DS_OK )
 597         {
 598             msg_Err( p_aout, "cannot start playing buffer" );
 599         }
 600     }
 601
 602     while( !p_notif->b_die )
 603     {
 604         aout_buffer_t *p_buffer;
 605         long l_latency;
 606
 607         /* wait for the position notification */
 608         i_which_frame = WaitForMultipleObjects( FRAMES_NUM,
 609                                                 notification_events, 0,
 610                                                 INFINITE ) - WAIT_OBJECT_0;
 611
 612         if( p_notif->b_die )
 613             break;
 614
 615         mtime = mdate();
 616
 617         /* We take into account the current latency */
 618         if( IDirectSoundBuffer_GetCurrentPosition(
 619                 p_aout->output.p_sys->p_dsbuffer,
 620                 &l_latency, NULL ) == DS_OK )
 621         {
 622             if( l_latency > (i_which_frame * FRAME_SIZE)
 623                   && l_latency < ((i_which_frame+1) * FRAME_SIZE) )
 624             {
 625                 l_latency = - ( l_latency /
 626                                 p_aout->output.output.i_bytes_per_frame %
 627                                 FRAME_SIZE );
 628             }
 629             else
 630             {
 631                 l_latency = FRAME_SIZE - ( l_latency /
 632                                       p_aout->output.output.i_bytes_per_frame %
 633                                       FRAME_SIZE );
 634             }
 635         }
 636         else
 637         {
 638             l_latency = 0;
 639         }
 640
 641         /* Mark last frame as empty */
 642         i_last_frame = (i_which_frame + FRAMES_NUM -1) % FRAMES_NUM;
 643         i_next_frame = (i_which_frame + 1) % FRAMES_NUM;
 644         p_notif->i_frame_status[i_last_frame] = FRAME_EMPTY;
 645
 646         /* Try to fill in as many frame buffers as possible */
 647         for( i = i_next_frame; (i % FRAMES_NUM) != i_which_frame; i++ )
 648         {
 649
 650             /* Check if frame buf is already filled */
 651             if( p_notif->i_frame_status[i % FRAMES_NUM] == FRAME_QUEUED )
 652                 continue;
 653
 654             p_buffer = aout_OutputNextBuffer( p_aout,
 655                 mtime + 1000000 / p_aout->output.output.i_rate *
 656                 ((i - i_next_frame + 1) * FRAME_SIZE + l_latency), VLC_FALSE );
 657
 658             /* If there is no audio data available and we have some buffered
 659              * already, then just wait for the next time */
 660             if( !p_buffer && (i != i_next_frame) )
 661             {
 662                 //msg_Err( p_aout, "only %i frame buffers filled!",
 663                 //         i - i_next_frame );
 664                 break;
 665             }
 666
 667             if( DirectxFillBuffer( p_aout, (i%FRAMES_NUM), p_buffer )
 668                 != VLC_SUCCESS )
 669                 break;
 670
 671             /* Mark the frame buffer as QUEUED */
 672             p_notif->i_frame_status[i%FRAMES_NUM] = FRAME_QUEUED;
 673         }
 674
 675     }
 676
 677     /* free the events */
 678     for( i = 0; i < FRAMES_NUM; i++ )
 679         CloseHandle( notification_events[i] );
 680
 681     msg_Dbg( p_notif, "DirectSoundThread exiting" );
 682 }