| 1 | /*************************************************************************** |
| 2 | oss.c - description |
| 3 | ------------------- |
| 4 | begin : Wed May 15 2002 |
| 5 | copyright : (C) 2002 by Pete Bernert |
| 6 | email : BlackDove@addcom.de |
| 7 | ***************************************************************************/ |
| 8 | /*************************************************************************** |
| 9 | * * |
| 10 | * This program is free software; you can redistribute it and/or modify * |
| 11 | * it under the terms of the GNU General Public License as published by * |
| 12 | * the Free Software Foundation; either version 2 of the License, or * |
| 13 | * (at your option) any later version. See also the license.txt file for * |
| 14 | * additional informations. * |
| 15 | * * |
| 16 | ***************************************************************************/ |
| 17 | |
| 18 | #include <stdio.h> |
| 19 | #include <string.h> |
| 20 | #include <sys/types.h> |
| 21 | #include <sys/stat.h> |
| 22 | #include <fcntl.h> |
| 23 | #include <sys/ioctl.h> |
| 24 | #include <unistd.h> |
| 25 | #include <sys/soundcard.h> |
| 26 | #include "out.h" |
| 27 | |
| 28 | //////////////////////////////////////////////////////////////////////// |
| 29 | // oss globals |
| 30 | //////////////////////////////////////////////////////////////////////// |
| 31 | |
| 32 | #define OSS_MODE_STEREO 1 |
| 33 | #define OSS_MODE_MONO 0 |
| 34 | |
| 35 | #define OSS_SPEED_44100 44100 |
| 36 | |
| 37 | #define FRAGMENT_SHIFT 12 |
| 38 | #define FRAGMENT_SIZE (1 << FRAGMENT_SHIFT) |
| 39 | |
| 40 | static int oss_audio_fd = -1; |
| 41 | extern int errno; |
| 42 | |
| 43 | //////////////////////////////////////////////////////////////////////// |
| 44 | // SETUP SOUND |
| 45 | //////////////////////////////////////////////////////////////////////// |
| 46 | |
| 47 | static int oss_init(void) |
| 48 | { |
| 49 | int pspeed=44100; |
| 50 | int pstereo; |
| 51 | int format; |
| 52 | int myfrag; |
| 53 | int oss_speed, oss_stereo; |
| 54 | |
| 55 | pstereo = OSS_MODE_STEREO; |
| 56 | oss_speed = pspeed; |
| 57 | oss_stereo = pstereo; |
| 58 | |
| 59 | if((oss_audio_fd=open("/dev/dsp",O_WRONLY,0))==-1) |
| 60 | { |
| 61 | printf("OSS device not available\n"); |
| 62 | return -1; |
| 63 | } |
| 64 | |
| 65 | if(ioctl(oss_audio_fd,SNDCTL_DSP_RESET,0)==-1) |
| 66 | { |
| 67 | printf("Sound reset failed\n"); |
| 68 | return -1; |
| 69 | } |
| 70 | |
| 71 | // we use 64 fragments with 1024 bytes each |
| 72 | // rearmed: now using 10*4096 for better latency |
| 73 | |
| 74 | myfrag = (10<<16) | FRAGMENT_SHIFT; |
| 75 | |
| 76 | if(ioctl(oss_audio_fd,SNDCTL_DSP_SETFRAGMENT,&myfrag)==-1) |
| 77 | { |
| 78 | printf("Sound set fragment failed!\n"); |
| 79 | return -1; |
| 80 | } |
| 81 | |
| 82 | format = AFMT_S16_NE; |
| 83 | |
| 84 | if(ioctl(oss_audio_fd,SNDCTL_DSP_SETFMT,&format) == -1) |
| 85 | { |
| 86 | printf("Sound format not supported!\n"); |
| 87 | return -1; |
| 88 | } |
| 89 | |
| 90 | if(format!=AFMT_S16_NE) |
| 91 | { |
| 92 | printf("Sound format not supported!\n"); |
| 93 | return -1; |
| 94 | } |
| 95 | |
| 96 | if(ioctl(oss_audio_fd,SNDCTL_DSP_STEREO,&oss_stereo)==-1 || !oss_stereo) |
| 97 | { |
| 98 | printf("Stereo mode not supported!\n"); |
| 99 | return -1; |
| 100 | } |
| 101 | |
| 102 | if(ioctl(oss_audio_fd,SNDCTL_DSP_SPEED,&oss_speed)==-1) |
| 103 | { |
| 104 | printf("Sound frequency not supported\n"); |
| 105 | return -1; |
| 106 | } |
| 107 | |
| 108 | if(oss_speed!=pspeed) |
| 109 | { |
| 110 | printf("Sound frequency not supported\n"); |
| 111 | return -1; |
| 112 | } |
| 113 | |
| 114 | return 0; |
| 115 | } |
| 116 | |
| 117 | //////////////////////////////////////////////////////////////////////// |
| 118 | // REMOVE SOUND |
| 119 | //////////////////////////////////////////////////////////////////////// |
| 120 | |
| 121 | static void oss_finish(void) |
| 122 | { |
| 123 | if(oss_audio_fd != -1 ) |
| 124 | { |
| 125 | close(oss_audio_fd); |
| 126 | oss_audio_fd = -1; |
| 127 | } |
| 128 | } |
| 129 | |
| 130 | //////////////////////////////////////////////////////////////////////// |
| 131 | // GET BUFFERED STATUS |
| 132 | //////////////////////////////////////////////////////////////////////// |
| 133 | |
| 134 | static int oss_busy(void) |
| 135 | { |
| 136 | audio_buf_info info; |
| 137 | unsigned long l; |
| 138 | |
| 139 | if(oss_audio_fd == -1) return 1; |
| 140 | if(ioctl(oss_audio_fd,SNDCTL_DSP_GETOSPACE,&info)==-1) |
| 141 | l=0; |
| 142 | else |
| 143 | { |
| 144 | if(info.fragments<(info.fragstotal>>1)) // can we write in at least the half of fragments? |
| 145 | l=1; // -> no? wait |
| 146 | else l=0; // -> else go on |
| 147 | } |
| 148 | |
| 149 | return l; |
| 150 | } |
| 151 | |
| 152 | //////////////////////////////////////////////////////////////////////// |
| 153 | // FEED SOUND DATA |
| 154 | //////////////////////////////////////////////////////////////////////// |
| 155 | |
| 156 | static void oss_feed(void *buf, int bytes) |
| 157 | { |
| 158 | audio_buf_info info; |
| 159 | char sbuf[4096]; |
| 160 | |
| 161 | if(oss_audio_fd == -1) return; |
| 162 | if(ioctl(oss_audio_fd,SNDCTL_DSP_GETOSPACE,&info)==0) |
| 163 | { |
| 164 | // for fast forward |
| 165 | if(bytes > info.fragments * FRAGMENT_SIZE) |
| 166 | bytes = info.fragments * FRAGMENT_SIZE; |
| 167 | if(bytes == 0) |
| 168 | return; |
| 169 | |
| 170 | if(info.fragments==info.fragstotal) |
| 171 | { |
| 172 | memset(sbuf, 0, sizeof(sbuf)); |
| 173 | write(oss_audio_fd, sbuf, sizeof(sbuf)); |
| 174 | write(oss_audio_fd, sbuf, sizeof(sbuf)); |
| 175 | write(oss_audio_fd, sbuf, sizeof(sbuf)); |
| 176 | } |
| 177 | } |
| 178 | |
| 179 | write(oss_audio_fd, buf, bytes); |
| 180 | } |
| 181 | |
| 182 | void out_register_oss(struct out_driver *drv) |
| 183 | { |
| 184 | drv->name = "oss"; |
| 185 | drv->init = oss_init; |
| 186 | drv->finish = oss_finish; |
| 187 | drv->busy = oss_busy; |
| 188 | drv->feed = oss_feed; |
| 189 | } |