mdw@git.distorted.org.uk Git - disorder/blob - server/speaker-oss.c

   1 /*
   2  * This file is part of DisOrder
   3  * Copyright (C) 2007, 2008 Richard Kettlewell
   4  * Portions copyright (C) 2007 Ross Younger
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  19  * USA
  20  */
  21 /** @file server/speaker-oss.c
  22  * @brief Support for @ref BACKEND_OSS */
  23
  24 #include <config.h>
  25
  26 #if HAVE_SYS_SOUNDCARD_H
  27
  28 #include "types.h"
  29
  30 #include <unistd.h>
  31 #include <poll.h>
  32 #include <string.h>
  33 #include <fcntl.h>
  34 #include <unistd.h>
  35 #include <errno.h>
  36 #include <sys/ioctl.h>
  37 #include <sys/soundcard.h>
  38
  39 #include "configuration.h"
  40 #include "syscalls.h"
  41 #include "log.h"
  42 #include "speaker-protocol.h"
  43 #include "speaker.h"
  44
  45 /** @brief Current device */
  46 static int ossfd = -1;
  47
  48 /** @brief OSS backend initialization */
  49 static void oss_init(void) {
  50   info("selected OSS backend");
  51 }
  52
  53 /** @brief OSS deactivation */
  54 static void oss_deactivate(void) {
  55   if(ossfd != -1) {
  56     xclose(ossfd);
  57     ossfd = -1;
  58     device_state = device_closed;
  59     D(("released audio device"));
  60   }
  61 }
  62
  63 /** @brief OSS backend activation */
  64 static void oss_activate(void) {
  65   int stereo, format, rate;
  66   const char *device;
  67
  68   if(ossfd == -1) {
  69     /* Try to pick a device */
  70     if(!strcmp(config->device, "default")) {
  71       if(access("/dev/dsp", W_OK) == 0)
  72         device = "/dev/dsp";
  73       else if(access("/dev/audio", W_OK) == 0)
  74         device = "/dev/audio";
  75       else {
  76         static int reported;
  77
  78         if(!reported) {
  79           error(0, "cannot determine default OSS device");
  80           reported = 1;
  81         }
  82         goto failed;
  83       }
  84     } else
  85       device = config->device;  /* just believe the user */
  86     /* Open the device */
  87     if((ossfd = open(device, O_WRONLY, 0)) < 0) {
  88       error(errno, "error opening %s", device);
  89       goto failed;
  90     }
  91     /* Set the audio format */
  92     stereo = (config->sample_format.channels == 2);
  93     if(ioctl(ossfd, SNDCTL_DSP_STEREO, &stereo) < 0) {
  94       error(errno, "error calling ioctl SNDCTL_DSP_STEREO %d", stereo);
  95       goto failed;
  96     }
  97     if(config->sample_format.bits == 8)
  98       format = AFMT_U8;
  99     else if(config->sample_format.bits == 16)
 100       format = (config->sample_format.endian == ENDIAN_LITTLE
 101                 ? AFMT_S16_LE : AFMT_S16_BE);
 102     else {
 103       error(0, "unsupported sample_format for oss backend");
 104       goto failed;
 105     }
 106     if(ioctl(ossfd, SNDCTL_DSP_SETFMT, &format) < 0) {
 107       error(errno, "error calling ioctl SNDCTL_DSP_SETFMT %#x", format);
 108       goto failed;
 109     }
 110     rate = config->sample_format.rate;
 111     if(ioctl(ossfd, SNDCTL_DSP_SPEED, &rate) < 0) {
 112       error(errno, "error calling ioctl SNDCTL_DSP_SPEED %d", rate);
 113       goto failed;
 114     }
 115     if((unsigned)rate != config->sample_format.rate)
 116       error(0, "asked for %luHz, got %dHz",
 117             (unsigned long)config->sample_format.rate, rate);
 118     nonblock(ossfd);
 119     device_state = device_open;
 120   }
 121   return;
 122 failed:
 123   device_state = device_error;
 124   if(ossfd >= 0) {
 125     xclose(ossfd);
 126     ossfd = -1;
 127   }
 128 }
 129
 130 /** @brief Play via OSS */
 131 static size_t oss_play(size_t frames) {
 132   const size_t bytes_to_play = frames * bpf;
 133   ssize_t bytes_written;
 134
 135   bytes_written = write(ossfd, playing->buffer + playing->start,
 136                         bytes_to_play);
 137   if(bytes_written < 0)
 138     switch(errno) {
 139     case EINTR:                 /* interruped */
 140     case EAGAIN:                /* overrun */
 141       return 0;                 /* try again later */
 142     default:
 143       fatal(errno, "error writing to audio device");
 144     }
 145   return bytes_written / bpf;
 146 }
 147
 148 static int oss_slot;
 149
 150 /** @brief Fill in poll fd array for OSS */
 151 static void oss_beforepoll(int attribute((unused)) *timeoutp) {
 152   oss_slot = addfd(ossfd, POLLOUT|POLLERR);
 153 }
 154
 155 /** @brief Process poll() results for OSS */
 156 static int oss_ready(void) {
 157   return !!(fds[oss_slot].revents & (POLLOUT|POLLERR));
 158 }
 159
 160 const struct speaker_backend oss_backend = {
 161   BACKEND_OSS,
 162   0,
 163   oss_init,
 164   oss_activate,
 165   oss_play,
 166   oss_deactivate,
 167   oss_beforepoll,
 168   oss_ready
 169 };
 170
 171 #endif
 172
 173 /*
 174 Local Variables:
 175 c-basic-offset:2
 176 comment-column:40
 177 fill-column:79
 178 indent-tabs-mode:nil
 179 End:
 180 */