Skip to content

Latest commit

 

History

History
365 lines (309 loc) · 10.4 KB

SDL_artsaudio.c

File metadata and controls

365 lines (309 loc) · 10.4 KB
 
1
2
/*
Simple DirectMedia Layer
Jan 2, 2016
Jan 2, 2016
3
Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
This software is provided 'as-is', without any express or implied
warranty. In no event will the authors be held liable for any damages
arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it
freely, subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not
claim that you wrote the original software. If you use this software
in a product, an acknowledgment in the product documentation would be
appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be
misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#include "../../SDL_internal.h"
#if SDL_AUDIO_DRIVER_ARTS
/* Allow access to a raw mixing buffer */
#ifdef HAVE_SIGNAL_H
#include <signal.h>
#endif
#include <unistd.h>
#include <errno.h>
#include "SDL_timer.h"
#include "SDL_audio.h"
#include "../SDL_audio_c.h"
#include "SDL_artsaudio.h"
#ifdef SDL_AUDIO_DRIVER_ARTS_DYNAMIC
#include "SDL_name.h"
#include "SDL_loadso.h"
#else
#define SDL_NAME(X) X
#endif
#ifdef SDL_AUDIO_DRIVER_ARTS_DYNAMIC
static const char *arts_library = SDL_AUDIO_DRIVER_ARTS_DYNAMIC;
static void *arts_handle = NULL;
/* !!! FIXME: I hate this SDL_NAME clutter...it makes everything so messy! */
static int (*SDL_NAME(arts_init)) (void);
static void (*SDL_NAME(arts_free)) (void);
static arts_stream_t(*SDL_NAME(arts_play_stream)) (int rate, int bits,
int channels,
const char *name);
static int (*SDL_NAME(arts_stream_set)) (arts_stream_t s,
arts_parameter_t param, int value);
static int (*SDL_NAME(arts_stream_get)) (arts_stream_t s,
arts_parameter_t param);
static int (*SDL_NAME(arts_write)) (arts_stream_t s, const void *buffer,
int count);
static void (*SDL_NAME(arts_close_stream)) (arts_stream_t s);
static int (*SDL_NAME(arts_suspend))(void);
static int (*SDL_NAME(arts_suspended)) (void);
static const char *(*SDL_NAME(arts_error_text)) (int errorcode);
#define SDL_ARTS_SYM(x) { #x, (void **) (char *) &SDL_NAME(x) }
static struct
{
const char *name;
void **func;
} arts_functions[] = {
/* *INDENT-OFF* */
SDL_ARTS_SYM(arts_init),
SDL_ARTS_SYM(arts_free),
SDL_ARTS_SYM(arts_play_stream),
SDL_ARTS_SYM(arts_stream_set),
SDL_ARTS_SYM(arts_stream_get),
SDL_ARTS_SYM(arts_write),
SDL_ARTS_SYM(arts_close_stream),
SDL_ARTS_SYM(arts_suspend),
SDL_ARTS_SYM(arts_suspended),
SDL_ARTS_SYM(arts_error_text),
/* *INDENT-ON* */
};
#undef SDL_ARTS_SYM
static void
UnloadARTSLibrary()
{
if (arts_handle != NULL) {
SDL_UnloadObject(arts_handle);
arts_handle = NULL;
}
}
static int
LoadARTSLibrary(void)
{
int i, retval = -1;
if (arts_handle == NULL) {
arts_handle = SDL_LoadObject(arts_library);
if (arts_handle != NULL) {
retval = 0;
for (i = 0; i < SDL_arraysize(arts_functions); ++i) {
*arts_functions[i].func =
SDL_LoadFunction(arts_handle, arts_functions[i].name);
if (!*arts_functions[i].func) {
retval = -1;
UnloadARTSLibrary();
break;
}
}
}
}
return retval;
}
#else
static void
UnloadARTSLibrary()
{
return;
}
static int
LoadARTSLibrary(void)
{
return 0;
}
#endif /* SDL_AUDIO_DRIVER_ARTS_DYNAMIC */
/* This function waits until it is possible to write a full sound buffer */
static void
ARTS_WaitDevice(_THIS)
{
Sint32 ticks;
/* Check to see if the thread-parent process is still alive */
{
static int cnt = 0;
/* Note that this only works with thread implementations
that use a different process id for each thread.
*/
/* Check every 10 loops */
if (this->hidden->parent && (((++cnt) % 10) == 0)) {
if (kill(this->hidden->parent, 0) < 0 && errno == ESRCH) {
SDL_OpenedAudioDeviceDisconnected(this);
}
}
}
/* Use timer for general audio synchronization */
ticks =
((Sint32) (this->hidden->next_frame - SDL_GetTicks())) - FUDGE_TICKS;
if (ticks > 0) {
SDL_Delay(ticks);
}
}
static void
ARTS_PlayDevice(_THIS)
{
/* Write the audio data */
int written = SDL_NAME(arts_write) (this->hidden->stream,
this->hidden->mixbuf,
this->hidden->mixlen);
/* If timer synchronization is enabled, set the next write frame */
if (this->hidden->frame_ticks) {
this->hidden->next_frame += this->hidden->frame_ticks;
}
/* If we couldn't write, assume fatal error for now */
if (written < 0) {
SDL_OpenedAudioDeviceDisconnected(this);
}
#ifdef DEBUG_AUDIO
fprintf(stderr, "Wrote %d bytes of audio data\n", written);
#endif
}
static Uint8 *
ARTS_GetDeviceBuf(_THIS)
{
return (this->hidden->mixbuf);
}
static void
ARTS_CloseDevice(_THIS)
{
Aug 5, 2016
Aug 5, 2016
198
199
if (this->hidden->stream) {
SDL_NAME(arts_close_stream) (this->hidden->stream);
Aug 5, 2016
Aug 5, 2016
201
SDL_NAME(arts_free) ();
Aug 5, 2016
Aug 5, 2016
202
SDL_free(this->hidden->mixbuf);
Aug 5, 2016
Aug 5, 2016
203
SDL_free(this->hidden);
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
}
static int
ARTS_Suspend(void)
{
const Uint32 abortms = SDL_GetTicks() + 3000; /* give up after 3 secs */
while ( (!SDL_NAME(arts_suspended)()) && !SDL_TICKS_PASSED(SDL_GetTicks(), abortms) ) {
if ( SDL_NAME(arts_suspend)() ) {
break;
}
}
return SDL_NAME(arts_suspended)();
}
static int
ARTS_OpenDevice(_THIS, void *handle, const char *devname, int iscapture)
{
int rc = 0;
int bits = 0, frag_spec = 0;
SDL_AudioFormat test_format = 0, format = 0;
/* Initialize all variables that we clean on shutdown */
this->hidden = (struct SDL_PrivateAudioData *)
SDL_malloc((sizeof *this->hidden));
if (this->hidden == NULL) {
return SDL_OutOfMemory();
}
Aug 5, 2016
Aug 5, 2016
231
SDL_zerop(this->hidden);
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
/* Try for a closest match on audio format */
for (test_format = SDL_FirstAudioFormat(this->spec.format);
!format && test_format;) {
#ifdef DEBUG_AUDIO
fprintf(stderr, "Trying format 0x%4.4x\n", test_format);
#endif
switch (test_format) {
case AUDIO_U8:
bits = 8;
format = 1;
break;
case AUDIO_S16LSB:
bits = 16;
format = 1;
break;
default:
format = 0;
break;
}
if (!format) {
test_format = SDL_NextAudioFormat();
}
}
if (format == 0) {
return SDL_SetError("Couldn't find any hardware audio formats");
}
this->spec.format = test_format;
if ((rc = SDL_NAME(arts_init) ()) != 0) {
return SDL_SetError("Unable to initialize ARTS: %s",
SDL_NAME(arts_error_text) (rc));
}
Aug 4, 2016
Aug 4, 2016
266
267
if (!ARTS_Suspend()) {
return SDL_SetError("ARTS can not open audio device");
Aug 4, 2016
Aug 4, 2016
270
271
272
273
274
275
276
277
this->hidden->stream = SDL_NAME(arts_play_stream) (this->spec.freq,
bits,
this->spec.channels,
"SDL");
/* Play nothing so we have at least one write (server bug workaround). */
SDL_NAME(arts_write) (this->hidden->stream, "", 0);
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
/* Calculate the final parameters for this audio specification */
SDL_CalculateAudioSpec(&this->spec);
/* Determine the power of two of the fragment size */
for (frag_spec = 0; (0x01 << frag_spec) < this->spec.size; ++frag_spec);
if ((0x01 << frag_spec) != this->spec.size) {
return SDL_SetError("Fragment size must be a power of two");
}
frag_spec |= 0x00020000; /* two fragments, for low latency */
#ifdef ARTS_P_PACKET_SETTINGS
SDL_NAME(arts_stream_set) (this->hidden->stream,
ARTS_P_PACKET_SETTINGS, frag_spec);
#else
SDL_NAME(arts_stream_set) (this->hidden->stream, ARTS_P_PACKET_SIZE,
frag_spec & 0xffff);
SDL_NAME(arts_stream_set) (this->hidden->stream, ARTS_P_PACKET_COUNT,
frag_spec >> 16);
#endif
this->spec.size = SDL_NAME(arts_stream_get) (this->hidden->stream,
ARTS_P_PACKET_SIZE);
/* Allocate mixing buffer */
this->hidden->mixlen = this->spec.size;
Aug 5, 2016
Aug 5, 2016
302
this->hidden->mixbuf = (Uint8 *) SDL_malloc(this->hidden->mixlen);
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
if (this->hidden->mixbuf == NULL) {
return SDL_OutOfMemory();
}
SDL_memset(this->hidden->mixbuf, this->spec.silence, this->spec.size);
/* Get the parent process id (we're the parent of the audio thread) */
this->hidden->parent = getpid();
/* We're ready to rock and roll. :-) */
return 0;
}
static void
ARTS_Deinitialize(void)
{
UnloadARTSLibrary();
}
static int
ARTS_Init(SDL_AudioDriverImpl * impl)
{
if (LoadARTSLibrary() < 0) {
return 0;
} else {
if (SDL_NAME(arts_init) () != 0) {
UnloadARTSLibrary();
SDL_SetError("ARTS: arts_init failed (no audio server?)");
return 0;
}
/* Play a stream so aRts doesn't crash */
if (ARTS_Suspend()) {
arts_stream_t stream;
stream = SDL_NAME(arts_play_stream) (44100, 16, 2, "SDL");
SDL_NAME(arts_write) (stream, "", 0);
SDL_NAME(arts_close_stream) (stream);
}
SDL_NAME(arts_free) ();
}
/* Set the function pointers */
impl->OpenDevice = ARTS_OpenDevice;
impl->PlayDevice = ARTS_PlayDevice;
impl->WaitDevice = ARTS_WaitDevice;
impl->GetDeviceBuf = ARTS_GetDeviceBuf;
impl->CloseDevice = ARTS_CloseDevice;
impl->Deinitialize = ARTS_Deinitialize;
impl->OnlyHasDefaultOutputDevice = 1;
return 1; /* this audio target is available. */
}
AudioBootStrap ARTS_bootstrap = {
"arts", "Analog RealTime Synthesizer", ARTS_Init, 0
};
#endif /* SDL_AUDIO_DRIVER_ARTS */
/* vi: set ts=4 sw=4 expandtab: */