modules/audio_output/jack.c

   1 /*****************************************************************************
   2  * jack : JACK audio output module
   3  *****************************************************************************
   4  * Copyright (C) 2006 the VideoLAN team
   5  * $Id$
   6  *
   7  * Authors: Cyril Deguet <asmax _at_ videolan.org>
   8  *          Jon Griffiths <jon_p_griffiths _At_ yahoo _DOT_ com>
   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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  23  *****************************************************************************/
  24 /**
  25  * \file modules/audio_output/jack.c
  26  * \brief JACK audio output functions
  27  */
  28 /*****************************************************************************
  29  * Preamble
  30  *****************************************************************************/
  31 #include <unistd.h>                                      /* write(), close() */
  32
  33 #ifdef HAVE_CONFIG_H
  34 # include "config.h"
  35 #endif
  36
  37 #include <vlc_common.h>
  38 #include <vlc_plugin.h>
  39 #include <vlc_aout.h>
  40
  41 #include <jack/jack.h>
  42
  43 typedef jack_default_audio_sample_t jack_sample_t;
  44
  45 /*****************************************************************************
  46  * aout_sys_t: JACK audio output method descriptor
  47  *****************************************************************************
  48  * This structure is part of the audio output thread descriptor.
  49  * It describes some JACK specific variables.
  50  *****************************************************************************/
  51 struct aout_sys_t
  52 {
  53     jack_client_t  *p_jack_client;
  54     jack_port_t   **p_jack_ports;
  55     jack_sample_t **p_jack_buffers;
  56     unsigned int    i_channels;
  57     jack_nframes_t latency;
  58 };
  59
  60 /*****************************************************************************
  61  * Local prototypes
  62  *****************************************************************************/
  63 static int  Open         ( vlc_object_t * );
  64 static void Close        ( vlc_object_t * );
  65 static void Play         ( aout_instance_t * );
  66 static int  Process      ( jack_nframes_t i_frames, void *p_arg );
  67 static int  GraphChange  ( void *p_arg );
  68
  69 #define AUTO_CONNECT_OPTION "jack-auto-connect"
  70 #define AUTO_CONNECT_TEXT N_("Automatically connect to writable clients")
  71 #define AUTO_CONNECT_LONGTEXT N_( \
  72     "If enabled, this option will automatically connect sound output to the " \
  73     "first writable JACK clients found." )
  74
  75 #define CONNECT_REGEX_OPTION "jack-connect-regex"
  76 #define CONNECT_REGEX_TEXT N_("Connect to clients matching")
  77 #define CONNECT_REGEX_LONGTEXT N_( \
  78     "If automatic connection is enabled, only JACK clients whose names " \
  79     "match this regular expression will be considered for connection." )
  80
  81 /*****************************************************************************
  82  * Module descriptor
  83  *****************************************************************************/
  84 vlc_module_begin ()
  85     set_shortname( "JACK" )
  86     set_description( N_("JACK audio output") )
  87     set_capability( "audio output", 100 )
  88     set_category( CAT_AUDIO )
  89     set_subcategory( SUBCAT_AUDIO_AOUT )
  90     add_bool( AUTO_CONNECT_OPTION, false, NULL, AUTO_CONNECT_TEXT,
  91               AUTO_CONNECT_LONGTEXT, true )
  92     add_string( CONNECT_REGEX_OPTION, NULL, CONNECT_REGEX_TEXT,
  93                 CONNECT_REGEX_LONGTEXT, true )
  94     set_callbacks( Open, Close )
  95 vlc_module_end ()
  96
  97 /*****************************************************************************
  98  * Open: create a JACK client
  99  *****************************************************************************/
 100 static int Open( vlc_object_t *p_this )
 101 {
 102     char psz_name[32];
 103     aout_instance_t *p_aout = (aout_instance_t *)p_this;
 104     struct aout_sys_t *p_sys = NULL;
 105     int status = VLC_SUCCESS;
 106     unsigned int i;
 107     int i_error;
 108
 109     /* Allocate structure */
 110     p_sys = calloc( 1, sizeof( aout_sys_t ) );
 111     if( p_sys == NULL )
 112     {
 113         status = VLC_ENOMEM;
 114         goto error_out;
 115     }
 116     p_aout->output.p_sys = p_sys;
 117     p_sys->latency = 0;
 118
 119     /* Connect to the JACK server */
 120     snprintf( psz_name, sizeof(psz_name), "vlc_%d", getpid());
 121     psz_name[sizeof(psz_name) - 1] = '\0';
 122     p_sys->p_jack_client = jack_client_open( psz_name,
 123                                              JackNullOption | JackNoStartServer,
 124                                              NULL );
 125     if( p_sys->p_jack_client == NULL )
 126     {
 127         msg_Err( p_aout, "failed to connect to JACK server" );
 128         status = VLC_EGENERIC;
 129         goto error_out;
 130     }
 131
 132     /* Set the process callback */
 133     jack_set_process_callback( p_sys->p_jack_client, Process, p_aout );
 134     jack_set_graph_order_callback ( p_sys->p_jack_client, GraphChange, p_aout );
 135
 136     p_aout->output.pf_play = Play;
 137     aout_VolumeSoftInit( p_aout );
 138
 139     /* JACK only supports fl32 format */
 140     p_aout->output.output.i_format = VLC_CODEC_FL32;
 141     // TODO add buffer size callback
 142     p_aout->output.i_nb_samples = jack_get_buffer_size( p_sys->p_jack_client );
 143     p_aout->output.output.i_rate = jack_get_sample_rate( p_sys->p_jack_client );
 144
 145     p_sys->i_channels = aout_FormatNbChannels( &p_aout->output.output );
 146
 147     p_sys->p_jack_ports = malloc( p_sys->i_channels *
 148                                   sizeof(jack_port_t *) );
 149     if( p_sys->p_jack_ports == NULL )
 150     {
 151         status = VLC_ENOMEM;
 152         goto error_out;
 153     }
 154
 155     p_sys->p_jack_buffers = malloc( p_sys->i_channels *
 156                                     sizeof(jack_sample_t *) );
 157     if( p_sys->p_jack_buffers == NULL )
 158     {
 159         status = VLC_ENOMEM;
 160         goto error_out;
 161     }
 162
 163     /* Create the output ports */
 164     for( i = 0; i < p_sys->i_channels; i++ )
 165     {
 166         snprintf( psz_name, sizeof(psz_name), "out_%d", i + 1);
 167         psz_name[sizeof(psz_name) - 1] = '\0';
 168         p_sys->p_jack_ports[i] = jack_port_register( p_sys->p_jack_client,
 169                 psz_name, JACK_DEFAULT_AUDIO_TYPE, JackPortIsOutput, 0 );
 170
 171         if( p_sys->p_jack_ports[i] == NULL )
 172         {
 173             msg_Err( p_aout, "failed to register a JACK port" );
 174             status = VLC_EGENERIC;
 175             goto error_out;
 176         }
 177     }
 178
 179     /* Tell the JACK server we are ready */
 180     i_error = jack_activate( p_sys->p_jack_client );
 181     if( i_error )
 182     {
 183         msg_Err( p_aout, "failed to activate JACK client (error %d)", i_error );
 184         status = VLC_EGENERIC;
 185         goto error_out;
 186     }
 187
 188     /* Auto connect ports if we were asked to */
 189     if( var_InheritBool( p_aout, AUTO_CONNECT_OPTION ) )
 190     {
 191         unsigned int i_in_ports;
 192         char *psz_regex = var_InheritString( p_aout, CONNECT_REGEX_OPTION );
 193         const char **pp_in_ports = jack_get_ports( p_sys->p_jack_client,
 194                                                    psz_regex, NULL,
 195                                                    JackPortIsInput );
 196         free( psz_regex );
 197         /* Count the number of returned ports */
 198         i_in_ports = 0;
 199         while( pp_in_ports && pp_in_ports[i_in_ports] )
 200         {
 201             i_in_ports++;
 202         }
 203
 204         /* Tie the output ports to JACK input ports */
 205         for( i = 0; i_in_ports > 0 && i < p_sys->i_channels; i++ )
 206         {
 207             const char* psz_in = pp_in_ports[i % i_in_ports];
 208             const char* psz_out = jack_port_name( p_sys->p_jack_ports[i] );
 209
 210             i_error = jack_connect( p_sys->p_jack_client, psz_out, psz_in );
 211             if( i_error )
 212             {
 213                 msg_Err( p_aout, "failed to connect port %s to port %s (error %d)",
 214                          psz_out, psz_in, i_error );
 215             }
 216             else
 217             {
 218                 msg_Dbg( p_aout, "connecting port %s to port %s",
 219                          psz_out, psz_in );
 220             }
 221         }
 222         free( pp_in_ports );
 223     }
 224
 225     msg_Dbg( p_aout, "JACK audio output initialized (%d channels, buffer "
 226              "size=%d, rate=%d)", p_sys->i_channels,
 227              p_aout->output.i_nb_samples, p_aout->output.output.i_rate );
 228
 229 error_out:
 230     /* Clean up, if an error occurred */
 231     if( status != VLC_SUCCESS && p_sys != NULL)
 232     {
 233         if( p_sys->p_jack_client )
 234         {
 235             jack_deactivate( p_sys->p_jack_client );
 236             jack_client_close( p_sys->p_jack_client );
 237         }
 238         free( p_sys->p_jack_ports );
 239         free( p_sys->p_jack_buffers );
 240         free( p_sys );
 241     }
 242     return status;
 243 }
 244
 245
 246 /*****************************************************************************
 247  * Process: callback for JACK
 248  *****************************************************************************/
 249 int Process( jack_nframes_t i_frames, void *p_arg )
 250 {
 251     unsigned int i, j, i_nb_samples = 0;
 252     aout_instance_t *p_aout = (aout_instance_t*) p_arg;
 253     struct aout_sys_t *p_sys = p_aout->output.p_sys;
 254     jack_sample_t *p_src = NULL;
 255
 256     jack_nframes_t dframes = p_sys->latency
 257                              - jack_frames_since_cycle_start( p_sys->p_jack_client );
 258
 259     jack_time_t dtime = dframes * 1000 * 1000 / jack_get_sample_rate( p_sys->p_jack_client );
 260     mtime_t play_date = mdate() + (mtime_t) ( dtime );
 261
 262     /* Get the next audio data buffer */
 263     aout_buffer_t *p_buffer = aout_OutputNextBuffer( p_aout, play_date, false );
 264
 265     if( p_buffer != NULL )
 266     {
 267         p_src = (jack_sample_t *)p_buffer->p_buffer;
 268         i_nb_samples = p_buffer->i_nb_samples;
 269     }
 270
 271     /* Get the JACK buffers to write to */
 272     for( i = 0; i < p_sys->i_channels; i++ )
 273     {
 274         p_sys->p_jack_buffers[i] = jack_port_get_buffer( p_sys->p_jack_ports[i],
 275                                                          i_frames );
 276     }
 277
 278     /* Copy in the audio data */
 279     for( j = 0; j < i_nb_samples; j++ )
 280     {
 281         for( i = 0; i < p_sys->i_channels; i++ )
 282         {
 283             jack_sample_t *p_dst = p_sys->p_jack_buffers[i];
 284             p_dst[j] = *p_src;
 285             p_src++;
 286         }
 287     }
 288
 289     /* Fill any remaining buffer with silence */
 290     if( i_nb_samples < i_frames )
 291     {
 292         for( i = 0; i < p_sys->i_channels; i++ )
 293         {
 294             memset( p_sys->p_jack_buffers[i] + i_nb_samples, 0,
 295                     sizeof( jack_sample_t ) * (i_frames - i_nb_samples) );
 296         }
 297     }
 298
 299     if( p_buffer )
 300     {
 301         aout_BufferFree( p_buffer );
 302     }
 303     return 0;
 304 }
 305
 306 /*****************************************************************************
 307  * GraphChange: callback when JACK reorders it's process graph.
 308                 We update latency information.
 309  *****************************************************************************/
 310
 311 static int GraphChange( void *p_arg )
 312 {
 313   aout_instance_t *p_aout = (aout_instance_t*) p_arg;
 314   struct aout_sys_t *p_sys = p_aout->output.p_sys;
 315   unsigned int i;
 316   jack_nframes_t port_latency;
 317
 318   p_sys->latency = 0;
 319
 320   for( i = 0; i < p_sys->i_channels; ++i )
 321   {
 322     port_latency = jack_port_get_total_latency( p_sys->p_jack_client,
 323                                                   p_sys->p_jack_ports[i] );
 324     p_sys->latency = __MAX( p_sys->latency, port_latency );
 325   }
 326
 327   msg_Dbg(p_aout, "JACK graph reordered. Our maximum latency=%d.", p_sys->latency);
 328
 329   return 0;
 330 }
 331
 332 /*****************************************************************************
 333  * Play: nothing to do
 334  *****************************************************************************/
 335 static void Play( aout_instance_t *p_aout )
 336 {
 337     VLC_UNUSED( p_aout );
 338 }
 339
 340 /*****************************************************************************
 341  * Close: close the JACK client
 342  *****************************************************************************/
 343 static void Close( vlc_object_t *p_this )
 344 {
 345     int i_error;
 346     aout_instance_t *p_aout = (aout_instance_t *)p_this;
 347     struct aout_sys_t *p_sys = p_aout->output.p_sys;
 348
 349     i_error = jack_deactivate( p_sys->p_jack_client );
 350     if( i_error )
 351     {
 352         msg_Err( p_aout, "jack_deactivate failed (error %d)", i_error );
 353     }
 354
 355     i_error = jack_client_close( p_sys->p_jack_client );
 356     if( i_error )
 357     {
 358         msg_Err( p_aout, "jack_client_close failed (error %d)", i_error );
 359     }
 360     free( p_sys->p_jack_ports );
 361     free( p_sys->p_jack_buffers );
 362     free( p_sys );
 363 }