src/audio/SDL_audiodev.c

   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 /* Get the name of the audio device we use for output */
  25
  26 #if SDL_AUDIO_DRIVER_BSD || SDL_AUDIO_DRIVER_OSS || SDL_AUDIO_DRIVER_SUNAUDIO
  27
  28 #include <fcntl.h>
  29 #include <sys/types.h>
  30 #include <sys/stat.h>
  31
  32 #include "SDL_stdinc.h"
  33 #include "SDL_audiodev_c.h"
  34
  35 #ifndef _PATH_DEV_DSP
  36 #if defined(__NETBSD__) || defined(__OPENBSD__)
  37 #define _PATH_DEV_DSP  "/dev/audio"
  38 #else
  39 #define _PATH_DEV_DSP  "/dev/dsp"
  40 #endif
  41 #endif
  42 #ifndef _PATH_DEV_DSP24
  43 #define _PATH_DEV_DSP24 "/dev/sound/dsp"
  44 #endif
  45 #ifndef _PATH_DEV_AUDIO
  46 #define _PATH_DEV_AUDIO "/dev/audio"
  47 #endif
  48
  49
  50 int SDL_OpenAudioPath(char *path, int maxlen, int flags, int classic)
  51 {
  52         const char *audiodev;
  53         int audio_fd;
  54         char audiopath[1024];
  55
  56         /* Figure out what our audio device is */
  57         if ( ((audiodev=SDL_getenv("SDL_PATH_DSP")) == NULL) &&
  58              ((audiodev=SDL_getenv("AUDIODEV")) == NULL) ) {
  59                 if ( classic ) {
  60                         audiodev = _PATH_DEV_AUDIO;
  61                 } else {
  62                         struct stat sb;
  63
  64                         /* Added support for /dev/sound/\* in Linux 2.4 */
  65                         if ( ((stat("/dev/sound", &sb) == 0) && S_ISDIR(sb.st_mode)) &&
  66                                  ((stat(_PATH_DEV_DSP24, &sb) == 0) && S_ISCHR(sb.st_mode)) ) {
  67                                 audiodev = _PATH_DEV_DSP24;
  68                         } else {
  69                                 audiodev = _PATH_DEV_DSP;
  70                         }
  71                 }
  72         }
  73         audio_fd = open(audiodev, flags, 0);
  74
  75         /* If the first open fails, look for other devices */
  76         if ( (audio_fd < 0) && (SDL_strlen(audiodev) < (sizeof(audiopath)-3)) ) {
  77                 int exists, instance;
  78                 struct stat sb;
  79
  80                 instance = 1;
  81                 do { /* Don't use errno ENOENT - it may not be thread-safe */
  82                         SDL_snprintf(audiopath, SDL_arraysize(audiopath),
  83                                      "%s%d", audiodev, instance++);
  84                         exists = 0;
  85                         if ( stat(audiopath, &sb) == 0 ) {
  86                                 exists = 1;
  87                                 audio_fd = open(audiopath, flags, 0);
  88                         }
  89                 } while ( exists && (audio_fd < 0) );
  90                 audiodev = audiopath;
  91         }
  92         if ( path != NULL ) {
  93                 SDL_strlcpy(path, audiodev, maxlen);
  94                 path[maxlen-1] = '\0';
  95         }
  96         return(audio_fd);
  97 }
  98
  99 #elif SDL_AUDIO_DRIVER_PAUD
 100
 101 /* Get the name of the audio device we use for output */
 102
 103 #include <sys/types.h>
 104 #include <sys/stat.h>
 105
 106 #include "SDL_stdinc.h"
 107 #include "SDL_audiodev_c.h"
 108
 109 #ifndef _PATH_DEV_DSP
 110 #define _PATH_DEV_DSP   "/dev/%caud%c/%c"
 111 #endif
 112
 113 char devsettings[][3] =
 114 {
 115     { 'p', '0', '1' }, { 'p', '0', '2' }, { 'p', '0', '3' }, { 'p', '0', '4' },
 116     { 'p', '1', '1' }, { 'p', '1', '2' }, { 'p', '1', '3' }, { 'p', '1', '4' },
 117     { 'p', '2', '1' }, { 'p', '2', '2' }, { 'p', '2', '3' }, { 'p', '2', '4' },
 118     { 'p', '3', '1' }, { 'p', '3', '2' }, { 'p', '3', '3' }, { 'p', '3', '4' },
 119     { 'b', '0', '1' }, { 'b', '0', '2' }, { 'b', '0', '3' }, { 'b', '0', '4' },
 120     { 'b', '1', '1' }, { 'b', '1', '2' }, { 'b', '1', '3' }, { 'b', '1', '4' },
 121     { 'b', '2', '1' }, { 'b', '2', '2' }, { 'b', '2', '3' }, { 'b', '2', '4' },
 122     { 'b', '3', '1' }, { 'b', '3', '2' }, { 'b', '3', '3' }, { 'b', '3', '4' },
 123     { '\0', '\0', '\0' }
 124 };
 125
 126 static int OpenUserDefinedDevice(char *path, int maxlen, int flags)
 127 {
 128         const char *audiodev;
 129         int  audio_fd;
 130
 131         /* Figure out what our audio device is */
 132         if ((audiodev=SDL_getenv("SDL_PATH_DSP")) == NULL) {
 133             audiodev=SDL_getenv("AUDIODEV");
 134         }
 135         if ( audiodev == NULL ) {
 136             return -1;
 137         }
 138         audio_fd = open(audiodev, flags, 0);
 139         if ( path != NULL ) {
 140                 SDL_strlcpy(path, audiodev, maxlen);
 141                 path[maxlen-1] = '\0';
 142         }
 143         return audio_fd;
 144 }
 145
 146 int SDL_OpenAudioPath(char *path, int maxlen, int flags, int classic)
 147 {
 148     struct stat sb;
 149     int         audio_fd;
 150     char        audiopath[1024];
 151     int         cycle;
 152
 153     audio_fd = OpenUserDefinedDevice(path,maxlen,flags);
 154     if ( audio_fd != -1 ) {
 155         return audio_fd;
 156     }
 157
 158     cycle    = 0;
 159     while( devsettings[cycle][0] != '\0' ) {
 160         SDL_snprintf( audiopath, SDL_arraysize(audiopath),
 161                  _PATH_DEV_DSP,
 162                  devsettings[cycle][0],
 163                  devsettings[cycle][1],
 164                  devsettings[cycle][2]);
 165
 166         if ( stat(audiopath, &sb) == 0 ) {
 167             audio_fd = open(audiopath, flags, 0);
 168             if ( audio_fd > 0 ) {
 169                 if ( path != NULL ) {
 170                     SDL_strlcpy( path, audiopath, maxlen );
 171                 }
 172                 return audio_fd;
 173             }
 174         }
 175     }
 176     return -1;
 177 }
 178
 179 #endif /* Audio driver selection */