src/audio/baudio/SDL_beaudio.cc
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FUNCTIONS
This source file includes following functions.
1 /*
2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997 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@devolution.com
21 */
22
23 #ifdef SAVE_RCSID
24 static char rcsid =
25 "@(#) $Id: SDL_beaudio.cc,v 1.1.2.3 2000/12/22 04:56:31 hercules Exp $";
26 #endif
27
28 /* Allow access to the audio stream on BeOS */
29
30 #include <stdlib.h>
31 #include <stdio.h>
32 #include <string.h>
33 #include <SoundPlayer.h>
34
35 #include "SDL_BeApp.h"
36
37 extern "C" {
38
39 #include "SDL_audio.h"
40 #include "SDL_audio_c.h"
41 #include "SDL_sysaudio.h"
42 #include "SDL_systhread_c.h"
43 #include "SDL_beaudio.h"
44
45
46 /* Audio driver functions */
47 static int BE_OpenAudio(_THIS, SDL_AudioSpec *spec);
48 static void BE_WaitAudio(_THIS);
49 static void BE_PlayAudio(_THIS);
50 static Uint8 *BE_GetAudioBuf(_THIS);
51 static void BE_CloseAudio(_THIS);
52
53 /* Audio driver bootstrap functions */
54
55 static int Audio_Available(void)
56 {
57 return(1);
58 }
59
60 static void Audio_DeleteDevice(SDL_AudioDevice *device)
61 {
62 free(device->hidden);
63 free(device);
64 }
65
66 static SDL_AudioDevice *Audio_CreateDevice(int devindex)
67 {
68 SDL_AudioDevice *device;
69
70 /* Initialize all variables that we clean on shutdown */
71 device = (SDL_AudioDevice *)malloc(sizeof(SDL_AudioDevice));
72 if ( device ) {
73 memset(device, 0, (sizeof *device));
74 device->hidden = (struct SDL_PrivateAudioData *)
75 malloc((sizeof *device->hidden));
76 }
77 if ( (device == NULL) || (device->hidden == NULL) ) {
78 SDL_OutOfMemory();
79 if ( device ) {
80 free(device);
81 }
82 return(0);
83 }
84 memset(device->hidden, 0, (sizeof *device->hidden));
85
86 /* Set the function pointers */
87 device->OpenAudio = BE_OpenAudio;
88 device->WaitAudio = BE_WaitAudio;
89 device->PlayAudio = BE_PlayAudio;
90 device->GetAudioBuf = BE_GetAudioBuf;
91 device->CloseAudio = BE_CloseAudio;
92
93 device->free = Audio_DeleteDevice;
94
95 return device;
96 }
97
98 AudioBootStrap BAUDIO_bootstrap = {
99 "baudio", "BeOS BSoundPlayer",
100 Audio_Available, Audio_CreateDevice
101 };
102
103 /* The BeOS callback for handling the audio buffer */
104 static void FillSound(void *device, void *stream, size_t len,
105 const media_raw_audio_format &format)
106 {
107 SDL_AudioDevice *audio = (SDL_AudioDevice *)device;
108
109 /* Silence the buffer, since it's ours */
110 memset(stream, audio->spec.silence, len);
111
112 /* Only do soemthing if audio is enabled */
113 if ( ! audio->enabled )
114 return;
115
116 if ( ! audio->paused ) {
117 if ( audio->convert.needed ) {
118 SDL_mutexP(audio->mixer_lock);
119 (*audio->spec.callback)(audio->spec.userdata,
120 (Uint8 *)audio->convert.buf,audio->convert.len);
121 SDL_mutexV(audio->mixer_lock);
122 SDL_ConvertAudio(&audio->convert);
123 memcpy(stream,audio->convert.buf,audio->convert.len_cvt);
124 } else {
125 SDL_mutexP(audio->mixer_lock);
126 (*audio->spec.callback)(audio->spec.userdata,
127 (Uint8 *)stream, len);
128 SDL_mutexV(audio->mixer_lock);
129 }
130 }
131 return;
132 }
133
134 /* Dummy functions -- we don't use thread-based audio */
135 void BE_WaitAudio(_THIS)
136 {
137 return;
138 }
139 void BE_PlayAudio(_THIS)
140 {
141 return;
142 }
143 Uint8 *BE_GetAudioBuf(_THIS)
144 {
145 return(NULL);
146 }
147
148 void BE_CloseAudio(_THIS)
149 {
150 if ( audio_obj ) {
151 audio_obj->Stop();
152 delete audio_obj;
153 audio_obj = NULL;
154 }
155
156 /* Quit the Be Application, if there's nothing left to do */
157 SDL_QuitBeApp();
158 }
159
160 int BE_OpenAudio(_THIS, SDL_AudioSpec *spec)
161 {
162 media_raw_audio_format format;
163
164 /* Initialize the Be Application, if it's not already started */
165 if ( SDL_InitBeApp() < 0 ) {
166 return(-1);
167 }
168
169 /* Parse the audio format and fill the Be raw audio format */
170 format.frame_rate = (float)spec->freq;
171 format.channel_count = spec->channels;
172 switch (spec->format&~0x1000) {
173 case AUDIO_S8:
174 /* Signed 8-bit audio unsupported, convert to U8 */
175 spec->format = AUDIO_U8;
176 case AUDIO_U8:
177 format.format = media_raw_audio_format::B_AUDIO_UCHAR;
178 format.byte_order = 0;
179 break;
180 case AUDIO_U16:
181 /* Unsigned 16-bit audio unsupported, convert to S16 */
182 spec->format ^= 0x8000;
183 case AUDIO_S16:
184 format.format = media_raw_audio_format::B_AUDIO_SHORT;
185 if ( spec->format & 0x1000 ) {
186 format.byte_order = 1; /* Big endian */
187 } else {
188 format.byte_order = 2; /* Little endian */
189 }
190 break;
191 }
192 format.buffer_size = spec->samples;
193
194 /* Calculate the final parameters for this audio specification */
195 SDL_CalculateAudioSpec(spec);
196
197 /* Subscribe to the audio stream (creates a new thread) */
198 { sigset_t omask;
199 SDL_MaskSignals(&omask);
200 audio_obj = new BSoundPlayer(&format, "SDL Audio", FillSound,
201 NULL, _this);
202 SDL_UnmaskSignals(&omask);
203 }
204 audio_obj->Start();
205 audio_obj->SetHasData(true);
206
207 /* We're running! */
208 return(1);
209 }
210
211 }; /* Extern C */