Mercurial > sdl-ios-xcode
annotate src/audio/dsp/SDL_dspaudio.c @ 315:3333b6e68289
Date: Sat, 23 Mar 2002 13:53:37 +0200
From: "Mike Gorchak" <mike@malva.ua>
Subject: Big QNX patch again.
Added 8bit palette emulation code for window mode with bpp>=15.
Added store/restore original palette for 8bit modes.
Added more information about photon API call fails.
Rewroten change palette code, slow but works.
Fixed bug with set caption before window was inited.
Fixed bugs with some initial state of variables.
Fixed bug with storing old video mode settings.
Fixed bug with switching to fullscreen mode and back.
Fixed few double SEGFAULTS during parachute mode.
Removed compilation warning with no PgWaitHWIdle prototype.
Removed pack of dead unusable code.
Cleanups SDL_PrivateVideoData structure, some headers.
Some code formatting.
| author | Sam Lantinga <slouken@libsdl.org> |
|---|---|
| date | Sat, 23 Mar 2002 20:19:44 +0000 |
| parents | f6ffac90895c |
| children | 30935e76acb5 |
| rev | line source |
|---|---|
| 0 | 1 /* |
| 2 SDL - Simple DirectMedia Layer | |
|
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Updated copyright information for 2002
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3 Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002 Sam Lantinga |
| 0 | 4 |
| 5 This library is free software; you can redistribute it and/or | |
| 6 modify it under the terms of the GNU Library General Public | |
| 7 License as published by the Free Software Foundation; either | |
| 8 version 2 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 Library General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU Library General Public | |
| 16 License along with this library; if not, write to the Free | |
| 17 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
| 18 | |
| 19 Sam Lantinga | |
|
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20 slouken@libsdl.org |
| 0 | 21 */ |
| 22 | |
| 23 #ifdef SAVE_RCSID | |
| 24 static char rcsid = | |
| 25 "@(#) $Id$"; | |
| 26 #endif | |
| 27 | |
| 28 /* Allow access to a raw mixing buffer */ | |
| 29 | |
| 30 #include <stdlib.h> | |
| 31 #include <stdio.h> | |
| 32 #include <string.h> | |
| 33 #include <errno.h> | |
| 34 #include <unistd.h> | |
| 35 #include <fcntl.h> | |
| 36 #include <signal.h> | |
| 37 #include <sys/time.h> | |
| 38 #include <sys/ioctl.h> | |
| 39 #include <sys/stat.h> | |
|
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40 #ifdef OSS_USE_SOUNDCARD_H |
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41 /* This is installed on some systems */ |
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42 #include <soundcard.h> |
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43 #else |
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44 /* This is recommended by OSS */ |
| 0 | 45 #include <sys/soundcard.h> |
|
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46 #endif |
| 0 | 47 |
| 48 #include "SDL_audio.h" | |
| 49 #include "SDL_error.h" | |
| 50 #include "SDL_audiomem.h" | |
| 51 #include "SDL_audio_c.h" | |
| 52 #include "SDL_timer.h" | |
| 53 #include "SDL_audiodev_c.h" | |
| 54 #include "SDL_dspaudio.h" | |
| 55 | |
| 56 /* The tag name used by DSP audio */ | |
| 57 #define DSP_DRIVER_NAME "dsp" | |
| 58 | |
| 59 /* Open the audio device for playback, and don't block if busy */ | |
|
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60 /*#define USE_BLOCKING_WRITES*/ |
| 0 | 61 #define OPEN_FLAGS (O_WRONLY|O_NONBLOCK) |
| 62 | |
| 63 /* Audio driver functions */ | |
| 64 static int DSP_OpenAudio(_THIS, SDL_AudioSpec *spec); | |
| 65 static void DSP_WaitAudio(_THIS); | |
| 66 static void DSP_PlayAudio(_THIS); | |
| 67 static Uint8 *DSP_GetAudioBuf(_THIS); | |
| 68 static void DSP_CloseAudio(_THIS); | |
| 69 | |
| 70 /* Audio driver bootstrap functions */ | |
| 71 | |
| 72 static int Audio_Available(void) | |
| 73 { | |
| 74 int fd; | |
| 75 int available; | |
| 76 | |
| 77 available = 0; | |
| 78 fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 0); | |
| 79 if ( fd >= 0 ) { | |
| 80 available = 1; | |
| 81 close(fd); | |
| 82 } | |
| 83 return(available); | |
| 84 } | |
| 85 | |
| 86 static void Audio_DeleteDevice(SDL_AudioDevice *device) | |
| 87 { | |
| 88 free(device->hidden); | |
| 89 free(device); | |
| 90 } | |
| 91 | |
| 92 static SDL_AudioDevice *Audio_CreateDevice(int devindex) | |
| 93 { | |
| 94 SDL_AudioDevice *this; | |
| 95 | |
| 96 /* Initialize all variables that we clean on shutdown */ | |
| 97 this = (SDL_AudioDevice *)malloc(sizeof(SDL_AudioDevice)); | |
| 98 if ( this ) { | |
| 99 memset(this, 0, (sizeof *this)); | |
| 100 this->hidden = (struct SDL_PrivateAudioData *) | |
| 101 malloc((sizeof *this->hidden)); | |
| 102 } | |
| 103 if ( (this == NULL) || (this->hidden == NULL) ) { | |
| 104 SDL_OutOfMemory(); | |
| 105 if ( this ) { | |
| 106 free(this); | |
| 107 } | |
| 108 return(0); | |
| 109 } | |
| 110 memset(this->hidden, 0, (sizeof *this->hidden)); | |
| 111 audio_fd = -1; | |
| 112 | |
| 113 /* Set the function pointers */ | |
| 114 this->OpenAudio = DSP_OpenAudio; | |
| 115 this->WaitAudio = DSP_WaitAudio; | |
| 116 this->PlayAudio = DSP_PlayAudio; | |
| 117 this->GetAudioBuf = DSP_GetAudioBuf; | |
| 118 this->CloseAudio = DSP_CloseAudio; | |
| 119 | |
| 120 this->free = Audio_DeleteDevice; | |
| 121 | |
| 122 return this; | |
| 123 } | |
| 124 | |
| 125 AudioBootStrap DSP_bootstrap = { | |
| 126 DSP_DRIVER_NAME, "OSS /dev/dsp standard audio", | |
| 127 Audio_Available, Audio_CreateDevice | |
| 128 }; | |
| 129 | |
| 130 /* This function waits until it is possible to write a full sound buffer */ | |
| 131 static void DSP_WaitAudio(_THIS) | |
| 132 { | |
| 133 /* Check to see if the thread-parent process is still alive */ | |
| 134 { static int cnt = 0; | |
| 135 /* Note that this only works with thread implementations | |
| 136 that use a different process id for each thread. | |
| 137 */ | |
| 138 if (parent && (((++cnt)%10) == 0)) { /* Check every 10 loops */ | |
| 139 if ( kill(parent, 0) < 0 ) { | |
| 140 this->enabled = 0; | |
| 141 } | |
| 142 } | |
| 143 } | |
| 144 | |
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145 #ifndef USE_BLOCKING_WRITES /* Not necessary when using blocking writes */ |
| 0 | 146 /* See if we need to use timed audio synchronization */ |
| 147 if ( frame_ticks ) { | |
| 148 /* Use timer for general audio synchronization */ | |
| 149 Sint32 ticks; | |
| 150 | |
| 151 ticks = ((Sint32)(next_frame - SDL_GetTicks()))-FUDGE_TICKS; | |
| 152 if ( ticks > 0 ) { | |
| 153 SDL_Delay(ticks); | |
| 154 } | |
| 155 } else { | |
| 156 /* Use select() for audio synchronization */ | |
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157 fd_set fdset; |
| 0 | 158 struct timeval timeout; |
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159 |
| 0 | 160 FD_ZERO(&fdset); |
| 161 FD_SET(audio_fd, &fdset); | |
| 162 timeout.tv_sec = 10; | |
| 163 timeout.tv_usec = 0; | |
| 164 #ifdef DEBUG_AUDIO | |
| 165 fprintf(stderr, "Waiting for audio to get ready\n"); | |
| 166 #endif | |
| 167 if ( select(audio_fd+1, NULL, &fdset, NULL, &timeout) <= 0 ) { | |
| 168 const char *message = | |
| 169 "Audio timeout - buggy audio driver? (disabled)"; | |
| 170 /* In general we should never print to the screen, | |
| 171 but in this case we have no other way of letting | |
| 172 the user know what happened. | |
| 173 */ | |
| 174 fprintf(stderr, "SDL: %s\n", message); | |
| 175 this->enabled = 0; | |
| 176 /* Don't try to close - may hang */ | |
| 177 audio_fd = -1; | |
| 178 #ifdef DEBUG_AUDIO | |
| 179 fprintf(stderr, "Done disabling audio\n"); | |
| 180 #endif | |
| 181 } | |
| 182 #ifdef DEBUG_AUDIO | |
| 183 fprintf(stderr, "Ready!\n"); | |
| 184 #endif | |
| 185 } | |
| 186 #endif /* !USE_BLOCKING_WRITES */ | |
| 187 } | |
| 188 | |
| 189 static void DSP_PlayAudio(_THIS) | |
| 190 { | |
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191 int written, p=0; |
| 0 | 192 |
| 193 /* Write the audio data, checking for EAGAIN on broken audio drivers */ | |
| 194 do { | |
|
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195 written = write(audio_fd, &mixbuf[p], mixlen-p); |
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196 if (written>0) |
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197 p += written; |
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198 if (written == -1 && errno != 0 && errno != EAGAIN && errno != EINTR) |
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199 { |
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200 /* Non recoverable error has occurred. It should be reported!!! */ |
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201 perror("audio"); |
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202 break; |
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203 } |
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204 |
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205 if ( p < written || ((written < 0) && ((errno == 0) || (errno == EAGAIN))) ) { |
| 0 | 206 SDL_Delay(1); /* Let a little CPU time go by */ |
| 207 } | |
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208 } while ( p < written ); |
| 0 | 209 |
| 210 /* If timer synchronization is enabled, set the next write frame */ | |
| 211 if ( frame_ticks ) { | |
| 212 next_frame += frame_ticks; | |
| 213 } | |
| 214 | |
| 215 /* If we couldn't write, assume fatal error for now */ | |
| 216 if ( written < 0 ) { | |
| 217 this->enabled = 0; | |
| 218 } | |
| 219 #ifdef DEBUG_AUDIO | |
| 220 fprintf(stderr, "Wrote %d bytes of audio data\n", written); | |
| 221 #endif | |
| 222 } | |
| 223 | |
| 224 static Uint8 *DSP_GetAudioBuf(_THIS) | |
| 225 { | |
| 226 return(mixbuf); | |
| 227 } | |
| 228 | |
| 229 static void DSP_CloseAudio(_THIS) | |
| 230 { | |
| 231 if ( mixbuf != NULL ) { | |
| 232 SDL_FreeAudioMem(mixbuf); | |
| 233 mixbuf = NULL; | |
| 234 } | |
| 235 if ( audio_fd >= 0 ) { | |
|
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236 int value; |
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237 ioctl(audio_fd, SNDCTL_DSP_RESET, &value); |
| 0 | 238 close(audio_fd); |
| 239 audio_fd = -1; | |
| 240 } | |
| 241 } | |
| 242 | |
| 243 static int DSP_ReopenAudio(_THIS, const char *audiodev, int format, | |
| 244 SDL_AudioSpec *spec) | |
| 245 { | |
| 246 int frag_spec; | |
| 247 int value; | |
| 248 | |
| 249 /* Close and then reopen the audio device */ | |
| 250 close(audio_fd); | |
| 251 audio_fd = open(audiodev, O_WRONLY, 0); | |
| 252 if ( audio_fd < 0 ) { | |
| 253 SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno)); | |
| 254 return(-1); | |
| 255 } | |
| 256 | |
| 257 /* Calculate the final parameters for this audio specification */ | |
| 258 SDL_CalculateAudioSpec(spec); | |
| 259 | |
| 260 /* Determine the power of two of the fragment size */ | |
| 261 for ( frag_spec = 0; (0x01<<frag_spec) < spec->size; ++frag_spec ); | |
| 262 if ( (0x01<<frag_spec) != spec->size ) { | |
| 263 SDL_SetError("Fragment size must be a power of two"); | |
| 264 return(-1); | |
| 265 } | |
| 266 frag_spec |= 0x00020000; /* two fragments, for low latency */ | |
| 267 | |
| 268 /* Set the audio buffering parameters */ | |
| 269 #ifdef DEBUG_AUDIO | |
| 270 fprintf(stderr, "Requesting %d fragments of size %d\n", | |
| 271 (frag_spec >> 16), 1<<(frag_spec&0xFFFF)); | |
| 272 #endif | |
| 273 if ( ioctl(audio_fd, SNDCTL_DSP_SETFRAGMENT, &frag_spec) < 0 ) { | |
| 274 fprintf(stderr, "Warning: Couldn't set audio fragment size\n"); | |
| 275 } | |
| 276 #ifdef DEBUG_AUDIO | |
| 277 { audio_buf_info info; | |
| 278 ioctl(audio_fd, SNDCTL_DSP_GETOSPACE, &info); | |
| 279 fprintf(stderr, "fragments = %d\n", info.fragments); | |
| 280 fprintf(stderr, "fragstotal = %d\n", info.fragstotal); | |
| 281 fprintf(stderr, "fragsize = %d\n", info.fragsize); | |
| 282 fprintf(stderr, "bytes = %d\n", info.bytes); | |
| 283 } | |
| 284 #endif | |
| 285 | |
| 286 /* Set the audio format */ | |
| 287 value = format; | |
| 288 if ( (ioctl(audio_fd, SNDCTL_DSP_SETFMT, &value) < 0) || | |
| 289 (value != format) ) { | |
| 290 SDL_SetError("Couldn't set audio format"); | |
| 291 return(-1); | |
| 292 } | |
| 293 | |
| 294 /* Set the number of channels of output */ | |
| 295 value = spec->channels; | |
| 296 #ifdef SNDCTL_DSP_CHANNELS | |
| 297 if ( ioctl(audio_fd, SNDCTL_DSP_CHANNELS, &value) < 0 ) { | |
| 298 #endif | |
| 299 value = (spec->channels > 1); | |
| 300 ioctl(audio_fd, SNDCTL_DSP_STEREO, &value); | |
| 301 value = (value ? 2 : 1); | |
| 302 #ifdef SNDCTL_DSP_CHANNELS | |
| 303 } | |
| 304 #endif | |
| 305 if ( value != spec->channels ) { | |
| 306 SDL_SetError("Couldn't set audio channels"); | |
| 307 return(-1); | |
| 308 } | |
| 309 | |
| 310 /* Set the DSP frequency */ | |
| 311 value = spec->freq; | |
| 312 if ( ioctl(audio_fd, SOUND_PCM_WRITE_RATE, &value) < 0 ) { | |
| 313 SDL_SetError("Couldn't set audio frequency"); | |
| 314 return(-1); | |
| 315 } | |
| 316 spec->freq = value; | |
| 317 | |
| 318 /* We successfully re-opened the audio */ | |
| 319 return(0); | |
| 320 } | |
| 321 | |
| 322 static int DSP_OpenAudio(_THIS, SDL_AudioSpec *spec) | |
| 323 { | |
| 324 char audiodev[1024]; | |
| 325 int format; | |
| 326 int value; | |
| 327 Uint16 test_format; | |
| 328 | |
| 329 /* Reset the timer synchronization flag */ | |
| 330 frame_ticks = 0.0; | |
| 331 | |
| 332 /* Open the audio device */ | |
| 333 audio_fd = SDL_OpenAudioPath(audiodev, sizeof(audiodev), OPEN_FLAGS, 0); | |
| 334 if ( audio_fd < 0 ) { | |
| 335 SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno)); | |
| 336 return(-1); | |
| 337 } | |
| 338 mixbuf = NULL; | |
| 339 | |
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340 #ifdef USE_BLOCKING_WRITES |
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341 /* Make the file descriptor use blocking writes with fcntl() */ |
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342 { long flags; |
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343 flags = fcntl(audio_fd, F_GETFL); |
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344 flags &= ~O_NONBLOCK; |
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345 if ( fcntl(audio_fd, F_SETFL, flags) < 0 ) { |
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346 SDL_SetError("Couldn't set audio blocking mode"); |
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347 return(-1); |
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348 } |
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349 } |
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350 #endif |
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351 |
| 0 | 352 /* Get a list of supported hardware formats */ |
| 353 if ( ioctl(audio_fd, SNDCTL_DSP_GETFMTS, &value) < 0 ) { | |
| 354 SDL_SetError("Couldn't get audio format list"); | |
| 355 return(-1); | |
| 356 } | |
| 357 | |
| 358 /* Try for a closest match on audio format */ | |
| 359 format = 0; | |
| 360 for ( test_format = SDL_FirstAudioFormat(spec->format); | |
| 361 ! format && test_format; ) { | |
| 362 #ifdef DEBUG_AUDIO | |
| 363 fprintf(stderr, "Trying format 0x%4.4x\n", test_format); | |
| 364 #endif | |
| 365 switch ( test_format ) { | |
| 366 case AUDIO_U8: | |
| 367 if ( value & AFMT_U8 ) { | |
| 368 format = AFMT_U8; | |
| 369 } | |
| 370 break; | |
| 371 case AUDIO_S8: | |
| 372 if ( value & AFMT_S8 ) { | |
| 373 format = AFMT_S8; | |
| 374 } | |
| 375 break; | |
| 376 case AUDIO_S16LSB: | |
| 377 if ( value & AFMT_S16_LE ) { | |
| 378 format = AFMT_S16_LE; | |
| 379 } | |
| 380 break; | |
| 381 case AUDIO_S16MSB: | |
| 382 if ( value & AFMT_S16_BE ) { | |
| 383 format = AFMT_S16_BE; | |
| 384 } | |
| 385 break; | |
| 386 case AUDIO_U16LSB: | |
| 387 if ( value & AFMT_U16_LE ) { | |
| 388 format = AFMT_U16_LE; | |
| 389 } | |
| 390 break; | |
| 391 case AUDIO_U16MSB: | |
| 392 if ( value & AFMT_U16_BE ) { | |
| 393 format = AFMT_U16_BE; | |
| 394 } | |
| 395 break; | |
| 396 default: | |
| 397 break; | |
| 398 } | |
| 399 if ( ! format ) { | |
| 400 test_format = SDL_NextAudioFormat(); | |
| 401 } | |
| 402 } | |
| 403 if ( format == 0 ) { | |
| 404 SDL_SetError("Couldn't find any hardware audio formats"); | |
| 405 return(-1); | |
| 406 } | |
| 407 spec->format = test_format; | |
| 408 | |
| 409 /* Set the audio format */ | |
| 410 value = format; | |
| 411 if ( (ioctl(audio_fd, SNDCTL_DSP_SETFMT, &value) < 0) || | |
| 412 (value != format) ) { | |
| 413 SDL_SetError("Couldn't set audio format"); | |
| 414 return(-1); | |
| 415 } | |
| 416 | |
| 417 /* Set the number of channels of output */ | |
| 418 value = spec->channels; | |
| 419 #ifdef SNDCTL_DSP_CHANNELS | |
| 420 if ( ioctl(audio_fd, SNDCTL_DSP_CHANNELS, &value) < 0 ) { | |
| 421 #endif | |
| 422 value = (spec->channels > 1); | |
| 423 ioctl(audio_fd, SNDCTL_DSP_STEREO, &value); | |
| 424 value = (value ? 2 : 1); | |
| 425 #ifdef SNDCTL_DSP_CHANNELS | |
| 426 } | |
| 427 #endif | |
| 428 spec->channels = value; | |
| 429 | |
| 430 /* Because some drivers don't allow setting the buffer size | |
| 431 after setting the format, we must re-open the audio device | |
| 432 once we know what format and channels are supported | |
| 433 */ | |
| 434 if ( DSP_ReopenAudio(this, audiodev, format, spec) < 0 ) { | |
| 435 /* Error is set by DSP_ReopenAudio() */ | |
| 436 return(-1); | |
| 437 } | |
| 438 | |
| 439 /* Allocate mixing buffer */ | |
| 440 mixlen = spec->size; | |
| 441 mixbuf = (Uint8 *)SDL_AllocAudioMem(mixlen); | |
| 442 if ( mixbuf == NULL ) { | |
| 443 return(-1); | |
| 444 } | |
| 445 memset(mixbuf, spec->silence, spec->size); | |
| 446 | |
| 447 #ifndef USE_BLOCKING_WRITES | |
| 448 /* Check to see if we need to use select() workaround */ | |
| 449 { char *workaround; | |
| 450 workaround = getenv("SDL_DSP_NOSELECT"); | |
| 451 if ( workaround ) { | |
| 452 frame_ticks = (float)(spec->samples*1000)/spec->freq; | |
| 453 next_frame = SDL_GetTicks()+frame_ticks; | |
| 454 } | |
| 455 } | |
| 456 #endif /* !USE_BLOCKING_WRITES */ | |
| 457 | |
| 458 /* Get the parent process id (we're the parent of the audio thread) */ | |
| 459 parent = getpid(); | |
| 460 | |
| 461 /* We're ready to rock and roll. :-) */ | |
| 462 return(0); | |
| 463 } |