1 /*
2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997-2012 Sam Lantinga
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
20 slouken@libsdl.org
21 */
22 #include "SDL_config.h"
23
24 /*
25 * Driver for native OpenBSD/NetBSD audio(4).
26 * vedge@vedge.com.ar.
27 */
28
29 #include <errno.h>
30 #include <unistd.h>
31 #include <fcntl.h>
32 #include <sys/time.h>
33 #include <sys/ioctl.h>
34 #include <sys/stat.h>
35 #include <sys/types.h>
36 #include <sys/audioio.h>
37
38 #include "SDL_timer.h"
39 #include "SDL_audio.h"
40 #include "../SDL_audiomem.h"
41 #include "../SDL_audio_c.h"
42 #include "../SDL_audiodev_c.h"
43 #include "SDL_bsdaudio.h"
44
45 /* The tag name used by NetBSD/OpenBSD audio */
46 #ifdef __NetBSD__
47 #define BSD_AUDIO_DRIVER_NAME "netbsd"
48 #define BSD_AUDIO_DRIVER_DESC "Native NetBSD audio"
49 #else
50 #define BSD_AUDIO_DRIVER_NAME "openbsd"
51 #define BSD_AUDIO_DRIVER_DESC "Native OpenBSD audio"
52 #endif
53
54 /* Open the audio device for playback, and don't block if busy */
55 /* #define USE_BLOCKING_WRITES */
56
57 /* Use timer for synchronization */
58 /* #define USE_TIMER_SYNC */
59
60 /* #define DEBUG_AUDIO */
61 /* #define DEBUG_AUDIO_STREAM */
62
63 #ifdef USE_BLOCKING_WRITES
64 #define OPEN_FLAGS O_WRONLY
65 #else
66 #define OPEN_FLAGS (O_WRONLY|O_NONBLOCK)
67 #endif
68
69 /* Audio driver functions */
70 static void OBSD_WaitAudio(_THIS);
71 static int OBSD_OpenAudio(_THIS, SDL_AudioSpec *spec);
72 static void OBSD_PlayAudio(_THIS);
73 static Uint8 *OBSD_GetAudioBuf(_THIS);
74 static void OBSD_CloseAudio(_THIS);
75
76 #ifdef DEBUG_AUDIO
77 static void OBSD_Status(_THIS);
78 #endif
79
80 /* Audio driver bootstrap functions */
81
82 static int
Audio_Available(void)83 Audio_Available(void)
84 {
85 int fd;
86 int available;
87
88 available = 0;
89 fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 0);
90 if(fd >= 0) {
91 available = 1;
92 close(fd);
93 }
94 return(available);
95 }
96
97 static void
Audio_DeleteDevice(SDL_AudioDevice * device)98 Audio_DeleteDevice(SDL_AudioDevice *device)
99 {
100 SDL_free(device->hidden);
101 SDL_free(device);
102 }
103
104 static SDL_AudioDevice
Audio_CreateDevice(int devindex)105 *Audio_CreateDevice(int devindex)
106 {
107 SDL_AudioDevice *this;
108
109 /* Initialize all variables that we clean on shutdown */
110 this = (SDL_AudioDevice*)SDL_malloc(sizeof(SDL_AudioDevice));
111 if(this) {
112 SDL_memset(this, 0, (sizeof *this));
113 this->hidden =
114 (struct SDL_PrivateAudioData*)SDL_malloc((sizeof *this->hidden));
115 }
116 if((this == NULL) || (this->hidden == NULL)) {
117 SDL_OutOfMemory();
118 if(this) SDL_free(this);
119 return(0);
120 }
121 SDL_memset(this->hidden, 0, (sizeof *this->hidden));
122 audio_fd = -1;
123
124 /* Set the function pointers */
125 this->OpenAudio = OBSD_OpenAudio;
126 this->WaitAudio = OBSD_WaitAudio;
127 this->PlayAudio = OBSD_PlayAudio;
128 this->GetAudioBuf = OBSD_GetAudioBuf;
129 this->CloseAudio = OBSD_CloseAudio;
130
131 this->free = Audio_DeleteDevice;
132
133 return this;
134 }
135
136 AudioBootStrap BSD_AUDIO_bootstrap = {
137 BSD_AUDIO_DRIVER_NAME, BSD_AUDIO_DRIVER_DESC,
138 Audio_Available, Audio_CreateDevice
139 };
140
141 /* This function waits until it is possible to write a full sound buffer */
142 static void
OBSD_WaitAudio(_THIS)143 OBSD_WaitAudio(_THIS)
144 {
145 #ifndef USE_BLOCKING_WRITES /* Not necessary when using blocking writes */
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 */
157 fd_set fdset;
158 struct timeval timeout;
159
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
OBSD_PlayAudio(_THIS)190 OBSD_PlayAudio(_THIS)
191 {
192 int written, p=0;
193
194 /* Write the audio data, checking for EAGAIN on broken audio drivers */
195 do {
196 written = write(audio_fd, &mixbuf[p], mixlen-p);
197 if (written>0)
198 p += written;
199 if (written == -1 && errno != 0 && errno != EAGAIN && errno != EINTR)
200 {
201 /* Non recoverable error has occurred. It should be reported!!! */
202 perror("audio");
203 break;
204 }
205
206 if ( p < written || ((written < 0) && ((errno == 0) || (errno == EAGAIN))) ) {
207 SDL_Delay(1); /* Let a little CPU time go by */
208 }
209 } while ( p < written );
210
211 /* If timer synchronization is enabled, set the next write frame */
212 if ( frame_ticks ) {
213 next_frame += frame_ticks;
214 }
215
216 /* If we couldn't write, assume fatal error for now */
217 if ( written < 0 ) {
218 this->enabled = 0;
219 }
220 #ifdef DEBUG_AUDIO
221 fprintf(stderr, "Wrote %d bytes of audio data\n", written);
222 #endif
223 }
224
225 static Uint8
OBSD_GetAudioBuf(_THIS)226 *OBSD_GetAudioBuf(_THIS)
227 {
228 return(mixbuf);
229 }
230
231 static void
OBSD_CloseAudio(_THIS)232 OBSD_CloseAudio(_THIS)
233 {
234 if(mixbuf != NULL) {
235 SDL_FreeAudioMem(mixbuf);
236 mixbuf = NULL;
237 }
238 if(audio_fd >= 0) {
239 close(audio_fd);
240 audio_fd = -1;
241 }
242 }
243
244 #ifdef DEBUG_AUDIO
245 void
OBSD_Status(_THIS)246 OBSD_Status(_THIS)
247 {
248 audio_info_t info;
249
250 if(ioctl(audio_fd, AUDIO_GETINFO, &info) < 0) {
251 fprintf(stderr,"AUDIO_GETINFO failed.\n");
252 return;
253 }
254
255 fprintf(stderr,"\n"
256 "[play/record info]\n"
257 "buffer size : %d bytes\n"
258 "sample rate : %i Hz\n"
259 "channels : %i\n"
260 "precision : %i-bit\n"
261 "encoding : 0x%x\n"
262 "seek : %i\n"
263 "sample count : %i\n"
264 "EOF count : %i\n"
265 "paused : %s\n"
266 "error occured : %s\n"
267 "waiting : %s\n"
268 "active : %s\n"
269 "",
270 info.play.buffer_size,
271 info.play.sample_rate,
272 info.play.channels,
273 info.play.precision,
274 info.play.encoding,
275 info.play.seek,
276 info.play.samples,
277 info.play.eof,
278 info.play.pause ? "yes" : "no",
279 info.play.error ? "yes" : "no",
280 info.play.waiting ? "yes" : "no",
281 info.play.active ? "yes": "no");
282
283 fprintf(stderr,"\n"
284 "[audio info]\n"
285 "monitor_gain : %i\n"
286 "hw block size : %d bytes\n"
287 "hi watermark : %i\n"
288 "lo watermark : %i\n"
289 "audio mode : %s\n"
290 "",
291 info.monitor_gain,
292 info.blocksize,
293 info.hiwat, info.lowat,
294 (info.mode == AUMODE_PLAY) ? "PLAY"
295 : (info.mode = AUMODE_RECORD) ? "RECORD"
296 : (info.mode == AUMODE_PLAY_ALL ? "PLAY_ALL"
297 : "?"));
298 }
299 #endif /* DEBUG_AUDIO */
300
301 static int
OBSD_OpenAudio(_THIS,SDL_AudioSpec * spec)302 OBSD_OpenAudio(_THIS, SDL_AudioSpec *spec)
303 {
304 char audiodev[64];
305 Uint16 format;
306 audio_info_t info;
307
308 AUDIO_INITINFO(&info);
309
310 /* Calculate the final parameters for this audio specification */
311 SDL_CalculateAudioSpec(spec);
312
313 #ifdef USE_TIMER_SYNC
314 frame_ticks = 0.0;
315 #endif
316
317 /* Open the audio device */
318 audio_fd = SDL_OpenAudioPath(audiodev, sizeof(audiodev), OPEN_FLAGS, 0);
319 if(audio_fd < 0) {
320 SDL_SetError("Couldn't open %s: %s", audiodev, strerror(errno));
321 return(-1);
322 }
323
324 /* Set to play mode */
325 info.mode = AUMODE_PLAY;
326 if(ioctl(audio_fd, AUDIO_SETINFO, &info) < 0) {
327 SDL_SetError("Couldn't put device into play mode");
328 return(-1);
329 }
330
331 mixbuf = NULL;
332 AUDIO_INITINFO(&info);
333 for (format = SDL_FirstAudioFormat(spec->format);
334 format; format = SDL_NextAudioFormat())
335 {
336 switch(format) {
337 case AUDIO_U8:
338 info.play.encoding = AUDIO_ENCODING_ULINEAR;
339 info.play.precision = 8;
340 break;
341 case AUDIO_S8:
342 info.play.encoding = AUDIO_ENCODING_SLINEAR;
343 info.play.precision = 8;
344 break;
345 case AUDIO_S16LSB:
346 info.play.encoding = AUDIO_ENCODING_SLINEAR_LE;
347 info.play.precision = 16;
348 break;
349 case AUDIO_S16MSB:
350 info.play.encoding = AUDIO_ENCODING_SLINEAR_BE;
351 info.play.precision = 16;
352 break;
353 case AUDIO_U16LSB:
354 info.play.encoding = AUDIO_ENCODING_ULINEAR_LE;
355 info.play.precision = 16;
356 break;
357 case AUDIO_U16MSB:
358 info.play.encoding = AUDIO_ENCODING_ULINEAR_BE;
359 info.play.precision = 16;
360 break;
361 default:
362 continue;
363 }
364 if (ioctl(audio_fd, AUDIO_SETINFO, &info) == 0)
365 break;
366 }
367
368 if(!format) {
369 SDL_SetError("No supported encoding for 0x%x", spec->format);
370 return(-1);
371 }
372
373 spec->format = format;
374
375 AUDIO_INITINFO(&info);
376 info.play.channels = spec->channels;
377 if (ioctl(audio_fd, AUDIO_SETINFO, &info) == -1)
378 spec->channels = 1;
379 AUDIO_INITINFO(&info);
380 info.play.sample_rate = spec->freq;
381 info.blocksize = spec->size;
382 info.hiwat = 5;
383 info.lowat = 3;
384 (void)ioctl(audio_fd, AUDIO_SETINFO, &info);
385 (void)ioctl(audio_fd, AUDIO_GETINFO, &info);
386 spec->freq = info.play.sample_rate;
387 /* Allocate mixing buffer */
388 mixlen = spec->size;
389 mixbuf = (Uint8*)SDL_AllocAudioMem(mixlen);
390 if(mixbuf == NULL) {
391 return(-1);
392 }
393 SDL_memset(mixbuf, spec->silence, spec->size);
394
395 /* Get the parent process id (we're the parent of the audio thread) */
396 parent = getpid();
397
398 #ifdef DEBUG_AUDIO
399 OBSD_Status(this);
400 #endif
401
402 /* We're ready to rock and roll. :-) */
403 return(0);
404 }
405