2 Copyright (C) 1996-1997 Id Software, Inc.
4 This program is free software; you can redistribute it and/or
5 modify it under the terms of the GNU General Public License
6 as published by the Free Software Foundation; either version 2
7 of the License, or (at your option) any later version.
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
13 See the GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the Free Software
17 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 #include <sys/param.h>
22 #include <sys/audioio.h>
23 #include <sys/endian.h>
24 #include <sys/ioctl.h>
33 static const int tryrates[] = {44100, 22051, 11025, 8000};
35 static int audio_fd = -1;
36 static qboolean snd_inited = false;
38 // TODO: allocate them in SNDDMA_Init, with a size depending on
39 // the sound format (enough for 0.5 sec of sound for instance)
40 #define SND_BUFF_SIZE 65536
41 static qbyte dma_buffer [SND_BUFF_SIZE];
42 static qbyte writebuf [SND_BUFF_SIZE];
45 qboolean SNDDMA_Init (void)
48 const char *snddev = _PATH_SOUND;
51 memset ((void*)shm, 0, sizeof (*shm));
53 // Open the audio device
54 audio_fd = open (snddev, O_WRONLY | O_NDELAY | O_NONBLOCK);
57 Con_Printf("Can't open the sound device (%s)\n", snddev);
61 // Look for an appropriate sound format
62 // TODO: we should also test mono/stereo and bits
63 // TODO: support "-sndspeed", "-sndbits", "-sndmono" and "-sndstereo"
66 for (i = 0; i < sizeof (tryrates) / sizeof (tryrates[0]); i++)
68 shm->speed = tryrates[i];
70 AUDIO_INITINFO (&info);
71 info.play.sample_rate = shm->speed;
72 info.play.channels = shm->channels;
73 info.play.precision = shm->samplebits;
74 // We only handle sound cards of the same endianess than the CPU
75 #if BYTE_ORDER == BIG_ENDIAN
76 info.play.encoding = AUDIO_ENCODING_SLINEAR_BE;
78 info.play.encoding = AUDIO_ENCODING_SLINEAR_LE;
80 if (ioctl (audio_fd, AUDIO_SETINFO, &info) == 0)
83 if (i == sizeof (tryrates) / sizeof (tryrates[0]))
85 Con_Print("Can't select an appropriate sound output format\n");
90 // Print some information
91 Con_Printf("%d bit %s sound initialized (rate: %dHz)\n",
93 (info.play.channels == 2) ? "stereo" : "mono",
94 info.play.sample_rate);
96 shm->samples = sizeof (dma_buffer) / (shm->samplebits / 8);
98 shm->buffer = dma_buffer;
104 int SNDDMA_GetDMAPos (void)
111 if (ioctl (audio_fd, AUDIO_GETINFO, &info) < 0)
113 Con_Print("Error: can't get audio info\n");
118 return ((info.play.samples * shm->channels) % shm->samples);
121 void SNDDMA_Shutdown (void)
135 Send sound to device if buffer isn't really the dma buffer
138 void SNDDMA_Submit (void)
142 static int wbufp = 0;
145 int stop = paintedtime;
150 if (paintedtime < wbufp)
153 bsize = shm->channels * (shm->samplebits / 8);
154 bytes = (paintedtime - wbufp) * bsize;
159 if (bytes > sizeof (writebuf))
161 bytes = sizeof (writebuf);
162 stop = wbufp + bytes / bsize;
165 // Transfert the sound data from the circular dma_buffer to writebuf
166 // TODO: using 2 memcpys instead of this loop should be faster
168 idx = (wbufp*bsize) & (sizeof (dma_buffer) - 1);
169 for (b = bytes; b; b--)
171 *p++ = dma_buffer[idx];
172 idx = (idx + 1) & (sizeof (dma_buffer) - 1);
175 if (write (audio_fd, writebuf, bytes) < bytes)
176 Con_Print("audio can't keep up!\n");
181 void *S_LockBuffer (void)
186 void S_UnlockBuffer (void)