|
1 /* |
|
2 SDL - Simple DirectMedia Layer |
|
3 Copyright (C) 1997-2006 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 Sam Lantinga |
|
20 slouken@libsdl.org |
|
21 */ |
|
22 #include "SDL_config.h" |
|
23 |
|
24 /* Allow access to a raw mixing buffer */ |
|
25 |
|
26 #include <fcntl.h> |
|
27 #include <errno.h> |
|
28 #ifdef __NETBSD__ |
|
29 #include <sys/ioctl.h> |
|
30 #include <sys/audioio.h> |
|
31 #endif |
|
32 #ifdef __SVR4 |
|
33 #include <sys/audioio.h> |
|
34 #else |
|
35 #include <sys/time.h> |
|
36 #include <sys/types.h> |
|
37 #endif |
|
38 #include <unistd.h> |
|
39 |
|
40 #include "SDL_timer.h" |
|
41 #include "SDL_audio.h" |
|
42 #include "../SDL_audiomem.h" |
|
43 #include "../SDL_audio_c.h" |
|
44 #include "../SDL_audiodev_c.h" |
|
45 #include "SDL_sunaudio.h" |
|
46 |
|
47 /* Open the audio device for playback, and don't block if busy */ |
|
48 #define OPEN_FLAGS (O_WRONLY|O_NONBLOCK) |
|
49 |
|
50 /* Audio driver functions */ |
|
51 static int DSP_OpenAudio(_THIS, SDL_AudioSpec *spec); |
|
52 static void DSP_WaitAudio(_THIS); |
|
53 static void DSP_PlayAudio(_THIS); |
|
54 static Uint8 *DSP_GetAudioBuf(_THIS); |
|
55 static void DSP_CloseAudio(_THIS); |
|
56 |
|
57 static Uint8 snd2au(int sample); |
|
58 |
|
59 /* Audio driver bootstrap functions */ |
|
60 |
|
61 static int Audio_Available(void) |
|
62 { |
|
63 int fd; |
|
64 int available; |
|
65 |
|
66 available = 0; |
|
67 fd = SDL_OpenAudioPath(NULL, 0, OPEN_FLAGS, 1); |
|
68 if ( fd >= 0 ) { |
|
69 available = 1; |
|
70 close(fd); |
|
71 } |
|
72 return(available); |
|
73 } |
|
74 |
|
75 static void Audio_DeleteDevice(SDL_AudioDevice *device) |
|
76 { |
|
77 SDL_free(device->hidden); |
|
78 SDL_free(device); |
|
79 } |
|
80 |
|
81 static SDL_AudioDevice *Audio_CreateDevice(int devindex) |
|
82 { |
|
83 SDL_AudioDevice *this; |
|
84 |
|
85 /* Initialize all variables that we clean on shutdown */ |
|
86 this = (SDL_AudioDevice *)SDL_malloc(sizeof(SDL_AudioDevice)); |
|
87 if ( this ) { |
|
88 SDL_memset(this, 0, (sizeof *this)); |
|
89 this->hidden = (struct SDL_PrivateAudioData *) |
|
90 SDL_malloc((sizeof *this->hidden)); |
|
91 } |
|
92 if ( (this == NULL) || (this->hidden == NULL) ) { |
|
93 SDL_OutOfMemory(); |
|
94 if ( this ) { |
|
95 SDL_free(this); |
|
96 } |
|
97 return(0); |
|
98 } |
|
99 SDL_memset(this->hidden, 0, (sizeof *this->hidden)); |
|
100 audio_fd = -1; |
|
101 |
|
102 /* Set the function pointers */ |
|
103 this->OpenAudio = DSP_OpenAudio; |
|
104 this->WaitAudio = DSP_WaitAudio; |
|
105 this->PlayAudio = DSP_PlayAudio; |
|
106 this->GetAudioBuf = DSP_GetAudioBuf; |
|
107 this->CloseAudio = DSP_CloseAudio; |
|
108 |
|
109 this->free = Audio_DeleteDevice; |
|
110 |
|
111 return this; |
|
112 } |
|
113 |
|
114 AudioBootStrap SUNAUDIO_bootstrap = { |
|
115 "audio", "UNIX /dev/audio interface", |
|
116 Audio_Available, Audio_CreateDevice |
|
117 }; |
|
118 |
|
119 #ifdef DEBUG_AUDIO |
|
120 void CheckUnderflow(_THIS) |
|
121 { |
|
122 #ifdef AUDIO_GETINFO |
|
123 audio_info_t info; |
|
124 int left; |
|
125 |
|
126 ioctl(audio_fd, AUDIO_GETINFO, &info); |
|
127 left = (written - info.play.samples); |
|
128 if ( written && (left == 0) ) { |
|
129 fprintf(stderr, "audio underflow!\n"); |
|
130 } |
|
131 #endif |
|
132 } |
|
133 #endif |
|
134 |
|
135 void DSP_WaitAudio(_THIS) |
|
136 { |
|
137 #ifdef AUDIO_GETINFO |
|
138 #define SLEEP_FUDGE 10 /* 10 ms scheduling fudge factor */ |
|
139 audio_info_t info; |
|
140 Sint32 left; |
|
141 |
|
142 ioctl(audio_fd, AUDIO_GETINFO, &info); |
|
143 left = (written - info.play.samples); |
|
144 if ( left > fragsize ) { |
|
145 Sint32 sleepy; |
|
146 |
|
147 sleepy = ((left - fragsize)/frequency); |
|
148 sleepy -= SLEEP_FUDGE; |
|
149 if ( sleepy > 0 ) { |
|
150 SDL_Delay(sleepy); |
|
151 } |
|
152 } |
|
153 #else |
|
154 fd_set fdset; |
|
155 |
|
156 FD_ZERO(&fdset); |
|
157 FD_SET(audio_fd, &fdset); |
|
158 select(audio_fd+1, NULL, &fdset, NULL, NULL); |
|
159 #endif |
|
160 } |
|
161 |
|
162 void DSP_PlayAudio(_THIS) |
|
163 { |
|
164 /* Write the audio data */ |
|
165 if ( ulaw_only ) { |
|
166 /* Assuming that this->spec.freq >= 8000 Hz */ |
|
167 int accum, incr, pos; |
|
168 Uint8 *aubuf; |
|
169 |
|
170 accum = 0; |
|
171 incr = this->spec.freq/8; |
|
172 aubuf = ulaw_buf; |
|
173 switch (audio_fmt & 0xFF) { |
|
174 case 8: { |
|
175 Uint8 *sndbuf; |
|
176 |
|
177 sndbuf = mixbuf; |
|
178 for ( pos=0; pos < fragsize; ++pos ) { |
|
179 *aubuf = snd2au((0x80-*sndbuf)*64); |
|
180 accum += incr; |
|
181 while ( accum > 0 ) { |
|
182 accum -= 1000; |
|
183 sndbuf += 1; |
|
184 } |
|
185 aubuf += 1; |
|
186 } |
|
187 } |
|
188 break; |
|
189 case 16: { |
|
190 Sint16 *sndbuf; |
|
191 |
|
192 sndbuf = (Sint16 *)mixbuf; |
|
193 for ( pos=0; pos < fragsize; ++pos ) { |
|
194 *aubuf = snd2au(*sndbuf/4); |
|
195 accum += incr; |
|
196 while ( accum > 0 ) { |
|
197 accum -= 1000; |
|
198 sndbuf += 1; |
|
199 } |
|
200 aubuf += 1; |
|
201 } |
|
202 } |
|
203 break; |
|
204 } |
|
205 #ifdef DEBUG_AUDIO |
|
206 CheckUnderflow(this); |
|
207 #endif |
|
208 if ( write(audio_fd, ulaw_buf, fragsize) < 0 ) { |
|
209 /* Assume fatal error, for now */ |
|
210 this->enabled = 0; |
|
211 } |
|
212 written += fragsize; |
|
213 } else { |
|
214 #ifdef DEBUG_AUDIO |
|
215 CheckUnderflow(this); |
|
216 #endif |
|
217 if ( write(audio_fd, mixbuf, this->spec.size) < 0 ) { |
|
218 /* Assume fatal error, for now */ |
|
219 this->enabled = 0; |
|
220 } |
|
221 written += fragsize; |
|
222 } |
|
223 } |
|
224 |
|
225 Uint8 *DSP_GetAudioBuf(_THIS) |
|
226 { |
|
227 return(mixbuf); |
|
228 } |
|
229 |
|
230 void DSP_CloseAudio(_THIS) |
|
231 { |
|
232 if ( mixbuf != NULL ) { |
|
233 SDL_FreeAudioMem(mixbuf); |
|
234 mixbuf = NULL; |
|
235 } |
|
236 if ( ulaw_buf != NULL ) { |
|
237 SDL_free(ulaw_buf); |
|
238 ulaw_buf = NULL; |
|
239 } |
|
240 close(audio_fd); |
|
241 } |
|
242 |
|
243 int DSP_OpenAudio(_THIS, SDL_AudioSpec *spec) |
|
244 { |
|
245 char audiodev[1024]; |
|
246 #ifdef AUDIO_SETINFO |
|
247 int enc; |
|
248 #endif |
|
249 int desired_freq = spec->freq; |
|
250 |
|
251 /* Initialize our freeable variables, in case we fail*/ |
|
252 audio_fd = -1; |
|
253 mixbuf = NULL; |
|
254 ulaw_buf = NULL; |
|
255 |
|
256 /* Determine the audio parameters from the AudioSpec */ |
|
257 switch ( spec->format & 0xFF ) { |
|
258 |
|
259 case 8: { /* Unsigned 8 bit audio data */ |
|
260 spec->format = AUDIO_U8; |
|
261 #ifdef AUDIO_SETINFO |
|
262 enc = AUDIO_ENCODING_LINEAR8; |
|
263 #endif |
|
264 } |
|
265 break; |
|
266 |
|
267 case 16: { /* Signed 16 bit audio data */ |
|
268 spec->format = AUDIO_S16SYS; |
|
269 #ifdef AUDIO_SETINFO |
|
270 enc = AUDIO_ENCODING_LINEAR; |
|
271 #endif |
|
272 } |
|
273 break; |
|
274 |
|
275 default: { |
|
276 SDL_SetError("Unsupported audio format"); |
|
277 return(-1); |
|
278 } |
|
279 } |
|
280 audio_fmt = spec->format; |
|
281 |
|
282 /* Open the audio device */ |
|
283 audio_fd = SDL_OpenAudioPath(audiodev, sizeof(audiodev), OPEN_FLAGS, 1); |
|
284 if ( audio_fd < 0 ) { |
|
285 SDL_SetError("Couldn't open %s: %s", audiodev, |
|
286 strerror(errno)); |
|
287 return(-1); |
|
288 } |
|
289 |
|
290 ulaw_only = 0; /* modern Suns do support linear audio */ |
|
291 #ifdef AUDIO_SETINFO |
|
292 for(;;) { |
|
293 audio_info_t info; |
|
294 AUDIO_INITINFO(&info); /* init all fields to "no change" */ |
|
295 |
|
296 /* Try to set the requested settings */ |
|
297 info.play.sample_rate = spec->freq; |
|
298 info.play.channels = spec->channels; |
|
299 info.play.precision = (enc == AUDIO_ENCODING_ULAW) |
|
300 ? 8 : spec->format & 0xff; |
|
301 info.play.encoding = enc; |
|
302 if( ioctl(audio_fd, AUDIO_SETINFO, &info) == 0 ) { |
|
303 |
|
304 /* Check to be sure we got what we wanted */ |
|
305 if(ioctl(audio_fd, AUDIO_GETINFO, &info) < 0) { |
|
306 SDL_SetError("Error getting audio parameters: %s", |
|
307 strerror(errno)); |
|
308 return -1; |
|
309 } |
|
310 if(info.play.encoding == enc |
|
311 && info.play.precision == (spec->format & 0xff) |
|
312 && info.play.channels == spec->channels) { |
|
313 /* Yow! All seems to be well! */ |
|
314 spec->freq = info.play.sample_rate; |
|
315 break; |
|
316 } |
|
317 } |
|
318 |
|
319 switch(enc) { |
|
320 case AUDIO_ENCODING_LINEAR8: |
|
321 /* unsigned 8bit apparently not supported here */ |
|
322 enc = AUDIO_ENCODING_LINEAR; |
|
323 spec->format = AUDIO_S16SYS; |
|
324 break; /* try again */ |
|
325 |
|
326 case AUDIO_ENCODING_LINEAR: |
|
327 /* linear 16bit didn't work either, resort to µ-law */ |
|
328 enc = AUDIO_ENCODING_ULAW; |
|
329 spec->channels = 1; |
|
330 spec->freq = 8000; |
|
331 spec->format = AUDIO_U8; |
|
332 ulaw_only = 1; |
|
333 break; |
|
334 |
|
335 default: |
|
336 /* oh well... */ |
|
337 SDL_SetError("Error setting audio parameters: %s", |
|
338 strerror(errno)); |
|
339 return -1; |
|
340 } |
|
341 } |
|
342 #endif /* AUDIO_SETINFO */ |
|
343 written = 0; |
|
344 |
|
345 /* We can actually convert on-the-fly to U-Law */ |
|
346 if ( ulaw_only ) { |
|
347 spec->freq = desired_freq; |
|
348 fragsize = (spec->samples*1000)/(spec->freq/8); |
|
349 frequency = 8; |
|
350 ulaw_buf = (Uint8 *)SDL_malloc(fragsize); |
|
351 if ( ulaw_buf == NULL ) { |
|
352 SDL_OutOfMemory(); |
|
353 return(-1); |
|
354 } |
|
355 spec->channels = 1; |
|
356 } else { |
|
357 fragsize = spec->samples; |
|
358 frequency = spec->freq/1000; |
|
359 } |
|
360 #ifdef DEBUG_AUDIO |
|
361 fprintf(stderr, "Audio device %s U-Law only\n", |
|
362 ulaw_only ? "is" : "is not"); |
|
363 fprintf(stderr, "format=0x%x chan=%d freq=%d\n", |
|
364 spec->format, spec->channels, spec->freq); |
|
365 #endif |
|
366 |
|
367 /* Update the fragment size as size in bytes */ |
|
368 SDL_CalculateAudioSpec(spec); |
|
369 |
|
370 /* Allocate mixing buffer */ |
|
371 mixbuf = (Uint8 *)SDL_AllocAudioMem(spec->size); |
|
372 if ( mixbuf == NULL ) { |
|
373 SDL_OutOfMemory(); |
|
374 return(-1); |
|
375 } |
|
376 SDL_memset(mixbuf, spec->silence, spec->size); |
|
377 |
|
378 /* We're ready to rock and roll. :-) */ |
|
379 return(0); |
|
380 } |
|
381 |
|
382 /************************************************************************/ |
|
383 /* This function (snd2au()) copyrighted: */ |
|
384 /************************************************************************/ |
|
385 /* Copyright 1989 by Rich Gopstein and Harris Corporation */ |
|
386 /* */ |
|
387 /* Permission to use, copy, modify, and distribute this software */ |
|
388 /* and its documentation for any purpose and without fee is */ |
|
389 /* hereby granted, provided that the above copyright notice */ |
|
390 /* appears in all copies and that both that copyright notice and */ |
|
391 /* this permission notice appear in supporting documentation, and */ |
|
392 /* that the name of Rich Gopstein and Harris Corporation not be */ |
|
393 /* used in advertising or publicity pertaining to distribution */ |
|
394 /* of the software without specific, written prior permission. */ |
|
395 /* Rich Gopstein and Harris Corporation make no representations */ |
|
396 /* about the suitability of this software for any purpose. It */ |
|
397 /* provided "as is" without express or implied warranty. */ |
|
398 /************************************************************************/ |
|
399 |
|
400 static Uint8 snd2au(int sample) |
|
401 { |
|
402 |
|
403 int mask; |
|
404 |
|
405 if (sample < 0) { |
|
406 sample = -sample; |
|
407 mask = 0x7f; |
|
408 } else { |
|
409 mask = 0xff; |
|
410 } |
|
411 |
|
412 if (sample < 32) { |
|
413 sample = 0xF0 | (15 - sample / 2); |
|
414 } else if (sample < 96) { |
|
415 sample = 0xE0 | (15 - (sample - 32) / 4); |
|
416 } else if (sample < 224) { |
|
417 sample = 0xD0 | (15 - (sample - 96) / 8); |
|
418 } else if (sample < 480) { |
|
419 sample = 0xC0 | (15 - (sample - 224) / 16); |
|
420 } else if (sample < 992) { |
|
421 sample = 0xB0 | (15 - (sample - 480) / 32); |
|
422 } else if (sample < 2016) { |
|
423 sample = 0xA0 | (15 - (sample - 992) / 64); |
|
424 } else if (sample < 4064) { |
|
425 sample = 0x90 | (15 - (sample - 2016) / 128); |
|
426 } else if (sample < 8160) { |
|
427 sample = 0x80 | (15 - (sample - 4064) / 256); |
|
428 } else { |
|
429 sample = 0x80; |
|
430 } |
|
431 return (mask & sample); |
|
432 } |