modules/access/oss.c

   1 /*****************************************************************************
   2  * oss.c : OSS input module for vlc
   3  *****************************************************************************
   4  * Copyright (C) 2002-2009 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Benjamin Pracht <bigben at videolan dot org>
   8  *          Richard Hosking <richard at hovis dot net>
   9  *          Antoine Cellerier <dionoea at videolan d.t org>
  10  *          Dennis Lou <dlou99 at yahoo dot com>
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  25  *****************************************************************************/
  26
  27 /*****************************************************************************
  28  * Preamble
  29  *****************************************************************************/
  30
  31 #ifdef HAVE_CONFIG_H
  32 # include "config.h"
  33 #endif
  34
  35 #include <vlc_common.h>
  36 #include <vlc_plugin.h>
  37 #include <vlc_access.h>
  38 #include <vlc_demux.h>
  39 #include <vlc_fs.h>
  40
  41 #include <fcntl.h>
  42 #include <unistd.h>
  43 #include <sys/ioctl.h>
  44 #include <sys/mman.h>
  45
  46 #ifdef HAVE_SYS_SOUNDCARD_H
  47 #  include <sys/soundcard.h>
  48 #endif
  49 #ifdef HAVE_SOUNDCARD_H
  50 #  include <soundcard.h>
  51 #endif
  52
  53 #include <poll.h>
  54
  55 /*****************************************************************************
  56  * Module descriptior
  57  *****************************************************************************/
  58
  59 static int  DemuxOpen ( vlc_object_t * );
  60 static void DemuxClose( vlc_object_t * );
  61
  62
  63 #define STEREO_TEXT N_( "Stereo" )
  64 #define STEREO_LONGTEXT N_( \
  65     "Capture the audio stream in stereo." )
  66 #define SAMPLERATE_TEXT N_( "Samplerate" )
  67 #define SAMPLERATE_LONGTEXT N_( \
  68     "Samplerate of the captured audio stream, in Hz (eg: 11025, 22050, 44100, 48000)" )
  69
  70 #define CACHING_TEXT N_("Caching value in ms")
  71 #define CACHING_LONGTEXT N_( \
  72     "Caching value for OSS captures. This " \
  73     "value should be set in milliseconds." )
  74
  75 #define OSS_DEFAULT "/dev/dsp"
  76
  77 #define CFG_PREFIX "oss-"
  78
  79 vlc_module_begin ()
  80     set_shortname( N_("OSS") )
  81     set_description( N_("OSS input") )
  82     set_category( CAT_INPUT )
  83     set_subcategory( SUBCAT_INPUT_ACCESS )
  84
  85     add_shortcut( "oss" )
  86     set_capability( "access_demux", 10 )
  87     set_callbacks( DemuxOpen, DemuxClose )
  88
  89     add_bool( CFG_PREFIX "stereo", true, NULL, STEREO_TEXT, STEREO_LONGTEXT,
  90                 true )
  91     add_integer( CFG_PREFIX "samplerate", 48000, NULL, SAMPLERATE_TEXT,
  92                 SAMPLERATE_LONGTEXT, true )
  93     add_integer( CFG_PREFIX "caching", DEFAULT_PTS_DELAY / 1000, NULL,
  94                 CACHING_TEXT, CACHING_LONGTEXT, true )
  95 vlc_module_end ()
  96
  97 /*****************************************************************************
  98  * Access: local prototypes
  99  *****************************************************************************/
 100
 101 static int DemuxControl( demux_t *, int, va_list );
 102
 103 static int Demux( demux_t * );
 104
 105 static block_t* GrabAudio( demux_t *p_demux );
 106
 107 static int OpenAudioDev( demux_t * );
 108 static int OpenAudioDevOss( demux_t * );
 109 static bool ProbeAudioDevOss( demux_t *, const char *psz_device );
 110
 111 struct buffer_t
 112 {
 113     void *  start;
 114     size_t  length;
 115 };
 116
 117 struct demux_sys_t
 118 {
 119     const char *psz_device;  /* OSS device from MRL */
 120
 121     int  i_fd;
 122
 123     /* Audio */
 124     int i_cache;
 125     unsigned int i_sample_rate;
 126     bool b_stereo;
 127     size_t i_max_frame_size;
 128     block_t *p_block;
 129     es_out_id_t *p_es;
 130
 131     int64_t i_next_demux_date; /* Used to handle oss:// as input-slave properly */
 132 };
 133
 134 static int FindMainDevice( demux_t *p_demux )
 135 {
 136     msg_Dbg( p_demux, "opening device '%s'", p_demux->p_sys->psz_device );
 137     if( ProbeAudioDevOss( p_demux, p_demux->p_sys->psz_device ) )
 138     {
 139         msg_Dbg( p_demux, "'%s' is an audio device", p_demux->p_sys->psz_device );
 140         p_demux->p_sys->i_fd = OpenAudioDev( p_demux );
 141     }
 142
 143     if( p_demux->p_sys->i_fd < 0 )
 144         return VLC_EGENERIC;
 145     return VLC_SUCCESS;
 146 }
 147
 148 /*****************************************************************************
 149  * DemuxOpen: opens oss device, access_demux callback
 150  *****************************************************************************
 151  *
 152  * url: <oss device>::::
 153  *
 154  *****************************************************************************/
 155 static int DemuxOpen( vlc_object_t *p_this )
 156 {
 157     demux_t     *p_demux = (demux_t*)p_this;
 158     demux_sys_t *p_sys;
 159
 160     /* Only when selected */
 161     if( *p_demux->psz_access == '\0' ) return VLC_EGENERIC;
 162
 163     /* Set up p_demux */
 164     p_demux->pf_control = DemuxControl;
 165     p_demux->pf_demux = Demux;
 166     p_demux->info.i_update = 0;
 167     p_demux->info.i_title = 0;
 168     p_demux->info.i_seekpoint = 0;
 169
 170     p_demux->p_sys = p_sys = calloc( 1, sizeof( demux_sys_t ) );
 171     if( p_sys == NULL ) return VLC_ENOMEM;
 172
 173     p_sys->i_sample_rate = var_InheritInteger( p_demux, CFG_PREFIX "samplerate" );
 174     p_sys->b_stereo = var_InheritBool( p_demux, CFG_PREFIX "stereo" );
 175     p_sys->i_cache = var_InheritInteger( p_demux, CFG_PREFIX "caching" );
 176     p_sys->i_fd = -1;
 177     p_sys->p_es = NULL;
 178     p_sys->p_block = NULL;
 179     p_sys->i_next_demux_date = -1;
 180
 181     if( p_demux->psz_location && *p_demux->psz_location )
 182         p_sys->psz_device = p_demux->psz_location;
 183     else
 184         p_sys->psz_device = OSS_DEFAULT;
 185
 186     if( FindMainDevice( p_demux ) != VLC_SUCCESS )
 187     {
 188         DemuxClose( p_this );
 189         return VLC_EGENERIC;
 190     }
 191
 192     return VLC_SUCCESS;
 193 }
 194
 195 /*****************************************************************************
 196  * Close: close device, free resources
 197  *****************************************************************************/
 198 static void DemuxClose( vlc_object_t *p_this )
 199 {
 200     demux_t     *p_demux = (demux_t *)p_this;
 201     demux_sys_t *p_sys   = p_demux->p_sys;
 202
 203     if( p_sys->i_fd >= 0 ) close( p_sys->i_fd );
 204
 205     if( p_sys->p_block ) block_Release( p_sys->p_block );
 206     free( p_sys );
 207 }
 208
 209 /*****************************************************************************
 210  * DemuxControl:
 211  *****************************************************************************/
 212 static int DemuxControl( demux_t *p_demux, int i_query, va_list args )
 213 {
 214     demux_sys_t *p_sys = p_demux->p_sys;
 215     bool *pb;
 216     int64_t    *pi64;
 217
 218     switch( i_query )
 219     {
 220         /* Special for access_demux */
 221         case DEMUX_CAN_PAUSE:
 222         case DEMUX_CAN_SEEK:
 223         case DEMUX_CAN_CONTROL_PACE:
 224             pb = (bool*)va_arg( args, bool * );
 225             *pb = false;
 226             return VLC_SUCCESS;
 227
 228         case DEMUX_GET_PTS_DELAY:
 229             pi64 = (int64_t*)va_arg( args, int64_t * );
 230             *pi64 = (int64_t)p_sys->i_cache * 1000;
 231             return VLC_SUCCESS;
 232
 233         case DEMUX_GET_TIME:
 234             pi64 = (int64_t*)va_arg( args, int64_t * );
 235             *pi64 = mdate();
 236             return VLC_SUCCESS;
 237
 238         case DEMUX_SET_NEXT_DEMUX_TIME:
 239             p_sys->i_next_demux_date = (int64_t)va_arg( args, int64_t );
 240             return VLC_SUCCESS;
 241
 242         /* TODO implement others */
 243         default:
 244             return VLC_EGENERIC;
 245     }
 246
 247     return VLC_EGENERIC;
 248 }
 249
 250 /*****************************************************************************
 251  * Demux: Processes the audio frame
 252  *****************************************************************************/
 253 static int Demux( demux_t *p_demux )
 254 {
 255     demux_sys_t *p_sys = p_demux->p_sys;
 256
 257     struct pollfd fd;
 258     fd.fd = p_sys->i_fd;
 259     fd.events = POLLIN|POLLPRI;
 260     fd.revents = 0;
 261
 262     block_t *p_block = NULL;
 263
 264     do
 265     {
 266         if( p_block )
 267         {
 268             es_out_Send( p_demux->out, p_sys->p_es, p_block );
 269             p_block = NULL;
 270         }
 271
 272         /* Wait for data */
 273         if( poll( &fd, 1, 10 ) ) /* Timeout after 0.01 seconds. Bigger delays are an issue when used with/as an input-slave since all the inputs run in the same thread. */
 274         {
 275             if( fd.revents & (POLLIN|POLLPRI) )
 276             {
 277                 p_block = GrabAudio( p_demux );
 278                 if( p_block )
 279                     es_out_Control( p_demux->out, ES_OUT_SET_PCR, p_block->i_pts );
 280             }
 281         }
 282     } while( p_block && p_sys->i_next_demux_date > 0 &&
 283              p_block->i_pts < p_sys->i_next_demux_date );
 284
 285     if( p_block )
 286         es_out_Send( p_demux->out, p_sys->p_es, p_block );
 287
 288     return 1;
 289 }
 290
 291 /*****************************************************************************
 292  * GrabAudio: Grab an audio frame
 293  *****************************************************************************/
 294 static block_t* GrabAudio( demux_t *p_demux )
 295 {
 296     demux_sys_t *p_sys = p_demux->p_sys;
 297     struct audio_buf_info buf_info;
 298     int i_read = 0, i_correct;
 299     block_t *p_block;
 300
 301     if( p_sys->p_block ) p_block = p_sys->p_block;
 302     else p_block = block_New( p_demux, p_sys->i_max_frame_size );
 303
 304     if( !p_block )
 305     {
 306         msg_Warn( p_demux, "cannot get block" );
 307         return 0;
 308     }
 309
 310     p_sys->p_block = p_block;
 311
 312     i_read = read( p_sys->i_fd, p_block->p_buffer,
 313                 p_sys->i_max_frame_size );
 314
 315     if( i_read <= 0 ) return 0;
 316
 317     p_block->i_buffer = i_read;
 318     p_sys->p_block = 0;
 319
 320     /* Correct the date because of kernel buffering */
 321     i_correct = i_read;
 322     if( ioctl( p_sys->i_fd, SNDCTL_DSP_GETISPACE, &buf_info ) == 0 )
 323     {
 324         i_correct += buf_info.bytes;
 325     }
 326
 327     /* Timestamp */
 328     p_block->i_pts = p_block->i_dts =
 329         mdate() - INT64_C(1000000) * (mtime_t)i_correct /
 330         2 / ( p_sys->b_stereo ? 2 : 1) / p_sys->i_sample_rate;
 331
 332     return p_block;
 333 }
 334
 335 /*****************************************************************************
 336  * OpenAudioDev: open and set up the audio device and probe for capabilities
 337  *****************************************************************************/
 338 static int OpenAudioDevOss( demux_t *p_demux )
 339 {
 340     int i_fd;
 341     int i_format;
 342
 343     i_fd = vlc_open( p_demux->p_sys->psz_device, O_RDONLY | O_NONBLOCK );
 344
 345     if( i_fd < 0 )
 346     {
 347         msg_Err( p_demux, "cannot open OSS audio device (%m)" );
 348         goto adev_fail;
 349     }
 350
 351     i_format = AFMT_S16_LE;
 352     if( ioctl( i_fd, SNDCTL_DSP_SETFMT, &i_format ) < 0
 353         || i_format != AFMT_S16_LE )
 354     {
 355         msg_Err( p_demux,
 356                  "cannot set audio format (16b little endian) (%m)" );
 357         goto adev_fail;
 358     }
 359
 360     if( ioctl( i_fd, SNDCTL_DSP_STEREO,
 361                &p_demux->p_sys->b_stereo ) < 0 )
 362     {
 363         msg_Err( p_demux, "cannot set audio channels count (%m)" );
 364         goto adev_fail;
 365     }
 366
 367     if( ioctl( i_fd, SNDCTL_DSP_SPEED,
 368                &p_demux->p_sys->i_sample_rate ) < 0 )
 369     {
 370         msg_Err( p_demux, "cannot set audio sample rate (%m)" );
 371         goto adev_fail;
 372     }
 373
 374     p_demux->p_sys->i_max_frame_size = 6 * 1024;
 375
 376     return i_fd;
 377
 378  adev_fail:
 379
 380     if( i_fd >= 0 ) close( i_fd );
 381     return -1;
 382 }
 383
 384 static int OpenAudioDev( demux_t *p_demux )
 385 {
 386     demux_sys_t *p_sys = p_demux->p_sys;
 387     int i_fd = OpenAudioDevOss( p_demux );
 388
 389     if( i_fd < 0 )
 390         return i_fd;
 391
 392     msg_Dbg( p_demux, "opened adev=`%s' %s %dHz",
 393              p_sys->psz_device, p_sys->b_stereo ? "stereo" : "mono",
 394              p_sys->i_sample_rate );
 395
 396     es_format_t fmt;
 397     es_format_Init( &fmt, AUDIO_ES, VLC_CODEC_S16L );
 398
 399     fmt.audio.i_channels = p_sys->b_stereo ? 2 : 1;
 400     fmt.audio.i_rate = p_sys->i_sample_rate;
 401     fmt.audio.i_bitspersample = 16;
 402     fmt.audio.i_blockalign = fmt.audio.i_channels * fmt.audio.i_bitspersample / 8;
 403     fmt.i_bitrate = fmt.audio.i_channels * fmt.audio.i_rate * fmt.audio.i_bitspersample;
 404
 405     msg_Dbg( p_demux, "new audio es %d channels %dHz",
 406              fmt.audio.i_channels, fmt.audio.i_rate );
 407
 408     p_sys->p_es = es_out_Add( p_demux->out, &fmt );
 409
 410     return i_fd;
 411 }
 412
 413 /*****************************************************************************
 414  * ProbeAudioDev: probe audio for capabilities
 415  *****************************************************************************/
 416 static bool ProbeAudioDevOss( demux_t *p_demux, const char *psz_device )
 417 {
 418     int i_caps;
 419     int i_fd = vlc_open( psz_device, O_RDONLY | O_NONBLOCK );
 420
 421     if( i_fd < 0 )
 422     {
 423         msg_Err( p_demux, "cannot open device %s for OSS audio (%m)", psz_device );
 424         goto open_failed;
 425     }
 426
 427     /* this will fail if the device is video */
 428     if( ioctl( i_fd, SNDCTL_DSP_GETCAPS, &i_caps ) < 0 )
 429     {
 430         msg_Err( p_demux, "cannot get audio caps (%m)" );
 431         goto open_failed;
 432     }
 433
 434     if( i_fd >= 0 ) close( i_fd );
 435
 436     return true;
 437
 438 open_failed:
 439     if( i_fd >= 0 ) close( i_fd );
 440     return false;
 441 }