src/audio/pulse/SDL_pulseaudio.c

   1 /*
   2     SDL - Simple DirectMedia Layer
   3     Copyright (C) 1997-2009 Sam Lantinga
   4
   5     This library is free software; you can redistribute it and/or
   6     modify it under the terms of the GNU Lesser General Public
   7     License as published by the Free Software Foundation; either
   8     version 2.1 of the License, or (at your option) any later version.
   9
  10     This library is distributed in the hope that it will be useful,
  11     but WITHOUT ANY WARRANTY; without even the implied warranty of
  12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13     Lesser General Public License for more details.
  14
  15     You should have received a copy of the GNU Lesser General Public
  16     License along with this library; if not, write to the Free Software
  17     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  18
  19     Stéphan Kochen
  20     stephan@kochen.nl
  21
  22     Based on parts of the ALSA and ESounD output drivers.
  23 */
  24 #include "SDL_config.h"
  25
  26 /* Allow access to an PulseAudio network stream mixing buffer */
  27
  28 #include <sys/types.h>
  29 #include <unistd.h>
  30 #include <signal.h>
  31 #include <errno.h>
  32 #include <pulse/pulseaudio.h>
  33 #include <pulse/simple.h>
  34
  35 #include "SDL_timer.h"
  36 #include "SDL_audio.h"
  37 #include "../SDL_audiomem.h"
  38 #include "../SDL_audio_c.h"
  39 #include "../SDL_audiodev_c.h"
  40 #include "SDL_pulseaudio.h"
  41
  42 #ifdef SDL_AUDIO_DRIVER_PULSE_DYNAMIC
  43 #include "SDL_name.h"
  44 #include "SDL_loadso.h"
  45 #else
  46 #define SDL_NAME(X)     X
  47 #endif
  48
  49 /* The tag name used by the driver */
  50 #define PULSE_DRIVER_NAME       "pulse"
  51
  52 /* Audio driver functions */
  53 static int PULSE_OpenAudio(_THIS, SDL_AudioSpec *spec);
  54 static void PULSE_WaitAudio(_THIS);
  55 static void PULSE_PlayAudio(_THIS);
  56 static Uint8 *PULSE_GetAudioBuf(_THIS);
  57 static void PULSE_CloseAudio(_THIS);
  58 static void PULSE_WaitDone(_THIS);
  59
  60 #ifdef SDL_AUDIO_DRIVER_PULSE_DYNAMIC
  61
  62 static const char *pulse_library = SDL_AUDIO_DRIVER_PULSE_DYNAMIC;
  63 static void *pulse_handle = NULL;
  64 static int pulse_loaded = 0;
  65
  66 static pa_simple* (*SDL_NAME(pa_simple_new))(
  67         const char *server,
  68         const char *name,
  69         pa_stream_direction_t dir,
  70         const char *dev,
  71         const char *stream_name,
  72         const pa_sample_spec *ss,
  73         const pa_channel_map *map,
  74         const pa_buffer_attr *attr,
  75         int *error
  76 );
  77 static void (*SDL_NAME(pa_simple_free))(pa_simple *s);
  78
  79 static pa_channel_map* (*SDL_NAME(pa_channel_map_init_auto))(
  80         pa_channel_map *m,
  81         unsigned channels,
  82         pa_channel_map_def_t def
  83 );
  84
  85 pa_mainloop * (*SDL_NAME(pa_mainloop_new))(void);
  86 pa_mainloop_api * (*SDL_NAME(pa_mainloop_get_api))(pa_mainloop *m);
  87 int (*SDL_NAME(pa_mainloop_iterate))(pa_mainloop *m, int block, int *retval);
  88 void (*SDL_NAME(pa_mainloop_free))(pa_mainloop *m);
  89
  90 pa_operation_state_t (*SDL_NAME(pa_operation_get_state))(pa_operation *o);
  91 void (*SDL_NAME(pa_operation_cancel))(pa_operation *o);
  92 void (*SDL_NAME(pa_operation_unref))(pa_operation *o);
  93
  94 pa_context * (*SDL_NAME(pa_context_new))(
  95         pa_mainloop_api *m, const char *name);
  96 int (*SDL_NAME(pa_context_connect))(
  97         pa_context *c, const char *server,
  98         pa_context_flags_t flags, const pa_spawn_api *api);
  99 pa_context_state_t (*SDL_NAME(pa_context_get_state))(pa_context *c);
 100 void (*SDL_NAME(pa_context_disconnect))(pa_context *c);
 101 void (*SDL_NAME(pa_context_unref))(pa_context *c);
 102
 103 pa_stream * (*SDL_NAME(pa_stream_new))(pa_context *c,
 104         const char *name, const pa_sample_spec *ss, const pa_channel_map *map);
 105 int (*SDL_NAME(pa_stream_connect_playback))(pa_stream *s, const char *dev,
 106         const pa_buffer_attr *attr, pa_stream_flags_t flags,
 107         pa_cvolume *volume, pa_stream *sync_stream);
 108 pa_stream_state_t (*SDL_NAME(pa_stream_get_state))(pa_stream *s);
 109 size_t (*SDL_NAME(pa_stream_writable_size))(pa_stream *s);
 110 int (*SDL_NAME(pa_stream_write))(pa_stream *s, const void *data, size_t nbytes,
 111         pa_free_cb_t free_cb, int64_t offset, pa_seek_mode_t seek);
 112 pa_operation * (*SDL_NAME(pa_stream_drain))(pa_stream *s,
 113         pa_stream_success_cb_t cb, void *userdata);
 114 int (*SDL_NAME(pa_stream_disconnect))(pa_stream *s);
 115 void (*SDL_NAME(pa_stream_unref))(pa_stream *s);
 116
 117 static struct {
 118         const char *name;
 119         void **func;
 120 } pulse_functions[] = {
 121         { "pa_simple_new",
 122                 (void **)&SDL_NAME(pa_simple_new)               },
 123         { "pa_simple_free",
 124                 (void **)&SDL_NAME(pa_simple_free)              },
 125         { "pa_channel_map_init_auto",
 126                 (void **)&SDL_NAME(pa_channel_map_init_auto)    },
 127         { "pa_mainloop_new",
 128                 (void **)&SDL_NAME(pa_mainloop_new)             },
 129         { "pa_mainloop_get_api",
 130                 (void **)&SDL_NAME(pa_mainloop_get_api)         },
 131         { "pa_mainloop_iterate",
 132                 (void **)&SDL_NAME(pa_mainloop_iterate)         },
 133         { "pa_mainloop_free",
 134                 (void **)&SDL_NAME(pa_mainloop_free)            },
 135         { "pa_operation_get_state",
 136                 (void **)&SDL_NAME(pa_operation_get_state)      },
 137         { "pa_operation_cancel",
 138                 (void **)&SDL_NAME(pa_operation_cancel)         },
 139         { "pa_operation_unref",
 140                 (void **)&SDL_NAME(pa_operation_unref)          },
 141         { "pa_context_new",
 142                 (void **)&SDL_NAME(pa_context_new)              },
 143         { "pa_context_connect",
 144                 (void **)&SDL_NAME(pa_context_connect)          },
 145         { "pa_context_get_state",
 146                 (void **)&SDL_NAME(pa_context_get_state)        },
 147         { "pa_context_disconnect",
 148                 (void **)&SDL_NAME(pa_context_disconnect)       },
 149         { "pa_context_unref",
 150                 (void **)&SDL_NAME(pa_context_unref)            },
 151         { "pa_stream_new",
 152                 (void **)&SDL_NAME(pa_stream_new)               },
 153         { "pa_stream_connect_playback",
 154                 (void **)&SDL_NAME(pa_stream_connect_playback)  },
 155         { "pa_stream_get_state",
 156                 (void **)&SDL_NAME(pa_stream_get_state)         },
 157         { "pa_stream_writable_size",
 158                 (void **)&SDL_NAME(pa_stream_writable_size)     },
 159         { "pa_stream_write",
 160                 (void **)&SDL_NAME(pa_stream_write)             },
 161         { "pa_stream_drain",
 162                 (void **)&SDL_NAME(pa_stream_drain)             },
 163         { "pa_stream_disconnect",
 164                 (void **)&SDL_NAME(pa_stream_disconnect)        },
 165         { "pa_stream_unref",
 166                 (void **)&SDL_NAME(pa_stream_unref)             },
 167 };
 168
 169 static void UnloadPulseLibrary()
 170 {
 171         if ( pulse_loaded ) {
 172                 SDL_UnloadObject(pulse_handle);
 173                 pulse_handle = NULL;
 174                 pulse_loaded = 0;
 175         }
 176 }
 177
 178 static int LoadPulseLibrary(void)
 179 {
 180         int i, retval = -1;
 181
 182         pulse_handle = SDL_LoadObject(pulse_library);
 183         if ( pulse_handle ) {
 184                 pulse_loaded = 1;
 185                 retval = 0;
 186                 for ( i=0; i<SDL_arraysize(pulse_functions); ++i ) {
 187                         *pulse_functions[i].func = SDL_LoadFunction(pulse_handle, pulse_functions[i].name);
 188                         if ( !*pulse_functions[i].func ) {
 189                                 retval = -1;
 190                                 UnloadPulseLibrary();
 191                                 break;
 192                         }
 193                 }
 194         }
 195         return retval;
 196 }
 197
 198 #else
 199
 200 static void UnloadPulseLibrary()
 201 {
 202         return;
 203 }
 204
 205 static int LoadPulseLibrary(void)
 206 {
 207         return 0;
 208 }
 209
 210 #endif /* SDL_AUDIO_DRIVER_PULSE_DYNAMIC */
 211
 212 /* Audio driver bootstrap functions */
 213
 214 static int Audio_Available(void)
 215 {
 216         pa_sample_spec paspec;
 217         pa_simple *connection;
 218         int available;
 219
 220         available = 0;
 221         if ( LoadPulseLibrary() < 0 ) {
 222                 return available;
 223         }
 224
 225         /* Connect with a dummy format. */
 226         paspec.format = PA_SAMPLE_U8;
 227         paspec.rate = 11025;
 228         paspec.channels = 1;
 229         connection = SDL_NAME(pa_simple_new)(
 230                 NULL,                        /* server */
 231                 "Test stream",               /* application name */
 232                 PA_STREAM_PLAYBACK,          /* playback mode */
 233                 NULL,                        /* device on the server */
 234                 "Simple DirectMedia Layer",  /* stream description */
 235                 &paspec,                     /* sample format spec */
 236                 NULL,                        /* channel map */
 237                 NULL,                        /* buffering attributes */
 238                 NULL                         /* error code */
 239         );
 240         if ( connection != NULL ) {
 241                 available = 1;
 242                 SDL_NAME(pa_simple_free)(connection);
 243         }
 244
 245         UnloadPulseLibrary();
 246         return(available);
 247 }
 248
 249 static void Audio_DeleteDevice(SDL_AudioDevice *device)
 250 {
 251         SDL_free(device->hidden);
 252         SDL_free(device);
 253         UnloadPulseLibrary();
 254 }
 255
 256 static SDL_AudioDevice *Audio_CreateDevice(int devindex)
 257 {
 258         SDL_AudioDevice *this;
 259
 260         /* Initialize all variables that we clean on shutdown */
 261         LoadPulseLibrary();
 262         this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice));
 263         if ( this ) {
 264                 SDL_memset(this, 0, (sizeof *this));
 265                 this->hidden = (struct SDL_PrivateAudioData *)
 266                                 SDL_malloc((sizeof *this->hidden));
 267         }
 268         if ( (this == NULL) || (this->hidden == NULL) ) {
 269                 SDL_OutOfMemory();
 270                 if ( this ) {
 271                         SDL_free(this);
 272                 }
 273                 return(0);
 274         }
 275         SDL_memset(this->hidden, 0, (sizeof *this->hidden));
 276
 277         /* Set the function pointers */
 278         this->OpenAudio = PULSE_OpenAudio;
 279         this->WaitAudio = PULSE_WaitAudio;
 280         this->PlayAudio = PULSE_PlayAudio;
 281         this->GetAudioBuf = PULSE_GetAudioBuf;
 282         this->CloseAudio = PULSE_CloseAudio;
 283         this->WaitDone = PULSE_WaitDone;
 284
 285         this->free = Audio_DeleteDevice;
 286
 287         return this;
 288 }
 289
 290 AudioBootStrap PULSE_bootstrap = {
 291         PULSE_DRIVER_NAME, "PulseAudio",
 292         Audio_Available, Audio_CreateDevice
 293 };
 294
 295 /* This function waits until it is possible to write a full sound buffer */
 296 static void PULSE_WaitAudio(_THIS)
 297 {
 298         int size;
 299         while(1) {
 300                 if (SDL_NAME(pa_context_get_state)(context) != PA_CONTEXT_READY ||
 301                     SDL_NAME(pa_stream_get_state)(stream) != PA_STREAM_READY ||
 302                     SDL_NAME(pa_mainloop_iterate)(mainloop, 1, NULL) < 0) {
 303                         this->enabled = 0;
 304                         return;
 305                 }
 306                 size = SDL_NAME(pa_stream_writable_size)(stream);
 307                 if (size >= mixlen)
 308                         return;
 309         }
 310 }
 311
 312 static void PULSE_PlayAudio(_THIS)
 313 {
 314         /* Write the audio data */
 315         if (SDL_NAME(pa_stream_write)(stream, mixbuf, mixlen, NULL, 0LL, PA_SEEK_RELATIVE) < 0)
 316                 this->enabled = 0;
 317 }
 318
 319 static Uint8 *PULSE_GetAudioBuf(_THIS)
 320 {
 321         return(mixbuf);
 322 }
 323
 324 static void PULSE_CloseAudio(_THIS)
 325 {
 326         if ( mixbuf != NULL ) {
 327                 SDL_FreeAudioMem(mixbuf);
 328                 mixbuf = NULL;
 329         }
 330         if ( stream != NULL ) {
 331                 SDL_NAME(pa_stream_disconnect)(stream);
 332                 SDL_NAME(pa_stream_unref)(stream);
 333                 stream = NULL;
 334         }
 335         if (context != NULL) {
 336                 SDL_NAME(pa_context_disconnect)(context);
 337                 SDL_NAME(pa_context_unref)(context);
 338                 context = NULL;
 339         }
 340         if (mainloop != NULL) {
 341                 SDL_NAME(pa_mainloop_free)(mainloop);
 342                 mainloop = NULL;
 343         }
 344 }
 345
 346 /* Try to get the name of the program */
 347 static char *get_progname(void)
 348 {
 349 #ifdef __LINUX__
 350         char *progname = NULL;
 351         FILE *fp;
 352         static char temp[BUFSIZ];
 353
 354         SDL_snprintf(temp, SDL_arraysize(temp), "/proc/%d/cmdline", getpid());
 355         fp = fopen(temp, "r");
 356         if ( fp != NULL ) {
 357                 if ( fgets(temp, sizeof(temp)-1, fp) ) {
 358                         progname = SDL_strrchr(temp, '/');
 359                         if ( progname == NULL ) {
 360                                 progname = temp;
 361                         } else {
 362                                 progname = progname+1;
 363                         }
 364                 }
 365                 fclose(fp);
 366         }
 367         return(progname);
 368 #elif defined(__NetBSD__)
 369         return getprogname();
 370 #else
 371         return("unknown");
 372 #endif
 373 }
 374
 375 static void stream_drain_complete(pa_stream *s, int success, void *userdata) {
 376 }
 377
 378 static void PULSE_WaitDone(_THIS)
 379 {
 380         pa_operation *o;
 381
 382         o = SDL_NAME(pa_stream_drain)(stream, stream_drain_complete, NULL);
 383         if (!o)
 384                 return;
 385
 386         while (SDL_NAME(pa_operation_get_state)(o) != PA_OPERATION_DONE) {
 387                 if (SDL_NAME(pa_context_get_state)(context) != PA_CONTEXT_READY ||
 388                     SDL_NAME(pa_stream_get_state)(stream) != PA_STREAM_READY ||
 389                     SDL_NAME(pa_mainloop_iterate)(mainloop, 1, NULL) < 0) {
 390                         SDL_NAME(pa_operation_cancel)(o);
 391                         break;
 392                 }
 393         }
 394         SDL_NAME(pa_operation_unref)(o);
 395 }
 396
 397 static int PULSE_OpenAudio(_THIS, SDL_AudioSpec *spec)
 398 {
 399         int             state;
 400         Uint16          test_format;
 401         pa_sample_spec  paspec;
 402         pa_buffer_attr  paattr;
 403         pa_channel_map  pacmap;
 404         pa_stream_flags_t flags = 0;
 405
 406         paspec.format = PA_SAMPLE_INVALID;
 407         for ( test_format = SDL_FirstAudioFormat(spec->format); test_format; ) {
 408                 switch ( test_format ) {
 409                         case AUDIO_U8:
 410                                 paspec.format = PA_SAMPLE_U8;
 411                                 break;
 412                         case AUDIO_S16LSB:
 413                                 paspec.format = PA_SAMPLE_S16LE;
 414                                 break;
 415                         case AUDIO_S16MSB:
 416                                 paspec.format = PA_SAMPLE_S16BE;
 417                                 break;
 418                 }
 419                 if ( paspec.format != PA_SAMPLE_INVALID )
 420                         break;
 421         }
 422         if (paspec.format == PA_SAMPLE_INVALID ) {
 423                 SDL_SetError("Couldn't find any suitable audio formats");
 424                 return(-1);
 425         }
 426         spec->format = test_format;
 427
 428         paspec.channels = spec->channels;
 429         paspec.rate = spec->freq;
 430
 431         /* Calculate the final parameters for this audio specification */
 432 #ifdef PA_STREAM_ADJUST_LATENCY
 433         spec->samples /= 2; /* Mix in smaller chunck to avoid underruns */
 434 #endif
 435         SDL_CalculateAudioSpec(spec);
 436
 437         /* Allocate mixing buffer */
 438         mixlen = spec->size;
 439         mixbuf = (Uint8 *)SDL_AllocAudioMem(mixlen);
 440         if ( mixbuf == NULL ) {
 441                 return(-1);
 442         }
 443         SDL_memset(mixbuf, spec->silence, spec->size);
 444
 445         /* Reduced prebuffering compared to the defaults. */
 446 #ifdef PA_STREAM_ADJUST_LATENCY
 447         paattr.tlength = mixlen * 4; /* 2x original requested bufsize */
 448         paattr.prebuf = -1;
 449         paattr.maxlength = -1;
 450         paattr.minreq = mixlen; /* -1 can lead to pa_stream_writable_size()
 451                                    >= mixlen never becoming true */
 452         flags = PA_STREAM_ADJUST_LATENCY;
 453 #else
 454         paattr.tlength = mixlen*2;
 455         paattr.prebuf = mixlen*2;
 456         paattr.maxlength = mixlen*2;
 457         paattr.minreq = mixlen;
 458 #endif
 459
 460         /* The SDL ALSA output hints us that we use Windows' channel mapping */
 461         /* http://bugzilla.libsdl.org/show_bug.cgi?id=110 */
 462         SDL_NAME(pa_channel_map_init_auto)(
 463                 &pacmap, spec->channels, PA_CHANNEL_MAP_WAVEEX);
 464
 465         /* Set up a new main loop */
 466         if (!(mainloop = SDL_NAME(pa_mainloop_new)())) {
 467                 PULSE_CloseAudio(this);
 468                 SDL_SetError("pa_mainloop_new() failed");
 469                 return(-1);
 470         }
 471
 472         mainloop_api = SDL_NAME(pa_mainloop_get_api)(mainloop);
 473         if (!(context = SDL_NAME(pa_context_new)(mainloop_api, get_progname()))) {
 474                 PULSE_CloseAudio(this);
 475                 SDL_SetError("pa_context_new() failed");
 476                 return(-1);
 477         }
 478
 479         /* Connect to the PulseAudio server */
 480         if (SDL_NAME(pa_context_connect)(context, NULL, 0, NULL) < 0) {
 481                 PULSE_CloseAudio(this);
 482                 SDL_SetError("Could not setup connection to PulseAudio");
 483                 return(-1);
 484         }
 485
 486         do {
 487                 if (SDL_NAME(pa_mainloop_iterate)(mainloop, 1, NULL) < 0) {
 488                         PULSE_CloseAudio(this);
 489                         SDL_SetError("pa_mainloop_iterate() failed");
 490                         return(-1);
 491                 }
 492                 state = SDL_NAME(pa_context_get_state)(context);
 493                 if (!PA_CONTEXT_IS_GOOD(state)) {
 494                         PULSE_CloseAudio(this);
 495                         SDL_SetError("Could not connect to PulseAudio");
 496                         return(-1);
 497                 }
 498         } while (state != PA_CONTEXT_READY);
 499
 500         stream = SDL_NAME(pa_stream_new)(
 501                 context,
 502                 "Simple DirectMedia Layer",  /* stream description */
 503                 &paspec,                     /* sample format spec */
 504                 &pacmap                      /* channel map */
 505         );
 506         if ( stream == NULL ) {
 507                 PULSE_CloseAudio(this);
 508                 SDL_SetError("Could not setup PulseAudio stream");
 509                 return(-1);
 510         }
 511
 512         if (SDL_NAME(pa_stream_connect_playback)(stream, NULL, &paattr, flags,
 513                         NULL, NULL) < 0) {
 514                 PULSE_CloseAudio(this);
 515                 SDL_SetError("Could not connect PulseAudio stream");
 516                 return(-1);
 517         }
 518
 519         do {
 520                 if (SDL_NAME(pa_mainloop_iterate)(mainloop, 1, NULL) < 0) {
 521                         PULSE_CloseAudio(this);
 522                         SDL_SetError("pa_mainloop_iterate() failed");
 523                         return(-1);
 524                 }
 525                 state = SDL_NAME(pa_stream_get_state)(stream);
 526                 if (!PA_STREAM_IS_GOOD(state)) {
 527                         PULSE_CloseAudio(this);
 528                         SDL_SetError("Could not create to PulseAudio stream");
 529                         return(-1);
 530                 }
 531         } while (state != PA_STREAM_READY);
 532
 533         return(0);
 534 }