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 "common.h"
  25
  26 #if HAVE_SYS_SOUNDCARD_H
  27
  28 #include <unistd.h>
  29 #include <poll.h>
  30 #include <fcntl.h>
  31 #include <unistd.h>
  32 #include <errno.h>
  33 #include <sys/ioctl.h>
  34 #include <sys/soundcard.h>
  35
  36 #include "configuration.h"
  37 #include "syscalls.h"
  38 #include "log.h"
  39 #include "speaker-protocol.h"
  40 #include "speaker.h"
  41
  42 /** @brief Current device */
  43 static int ossfd = -1;
  44
  45 /** @brief OSS backend initialization */
  46 static void oss_init(void) {
  47   info("selected OSS backend");
  48 }
  49
  50 /** @brief OSS deactivation */
  51 static void oss_deactivate(void) {
  52   if(ossfd != -1) {
  53     xclose(ossfd);
  54     ossfd = -1;
  55     device_state = device_closed;
  56     D(("released audio device"));
  57   }
  58 }
  59
  60 /** @brief OSS backend activation */
  61 static void oss_activate(void) {
  62   int stereo, format, rate;
  63   const char *device;
  64
  65   if(ossfd == -1) {
  66     /* Try to pick a device */
  67     if(!strcmp(config->device, "default")) {
  68       if(access("/dev/dsp", W_OK) == 0)
  69         device = "/dev/dsp";
  70       else if(access("/dev/audio", W_OK) == 0)
  71         device = "/dev/audio";
  72       else {
  73         static int reported;
  74
  75         if(!reported) {
  76           error(0, "cannot determine default OSS device");
  77           reported = 1;
  78         }
  79         goto failed;
  80       }
  81     } else
  82       device = config->device;  /* just believe the user */
  83     /* Open the device */
  84     if((ossfd = open(device, O_WRONLY, 0)) < 0) {
  85       error(errno, "error opening %s", device);
  86       goto failed;
  87     }
  88     /* Set the audio format */
  89     stereo = (config->sample_format.channels == 2);
  90     if(ioctl(ossfd, SNDCTL_DSP_STEREO, &stereo) < 0) {
  91       error(errno, "error calling ioctl SNDCTL_DSP_STEREO %d", stereo);
  92       goto failed;
  93     }
  94     if(config->sample_format.bits == 8)
  95       format = AFMT_U8;
  96     else if(config->sample_format.bits == 16)
  97       format = (config->sample_format.endian == ENDIAN_LITTLE
  98                 ? AFMT_S16_LE : AFMT_S16_BE);
  99     else {
 100       error(0, "unsupported sample_format for oss backend");
 101       goto failed;
 102     }
 103     if(ioctl(ossfd, SNDCTL_DSP_SETFMT, &format) < 0) {
 104       error(errno, "error calling ioctl SNDCTL_DSP_SETFMT %#x", format);
 105       goto failed;
 106     }
 107     rate = config->sample_format.rate;
 108     if(ioctl(ossfd, SNDCTL_DSP_SPEED, &rate) < 0) {
 109       error(errno, "error calling ioctl SNDCTL_DSP_SPEED %d", rate);
 110       goto failed;
 111     }
 112     if((unsigned)rate != config->sample_format.rate)
 113       error(0, "asked for %luHz, got %dHz",
 114             (unsigned long)config->sample_format.rate, rate);
 115     nonblock(ossfd);
 116     device_state = device_open;
 117   }
 118   return;
 119 failed:
 120   device_state = device_error;
 121   if(ossfd >= 0) {
 122     xclose(ossfd);
 123     ossfd = -1;
 124   }
 125 }
 126
 127 /** @brief Play via OSS */
 128 static size_t oss_play(size_t frames) {
 129   const size_t bytes_to_play = frames * bpf;
 130   ssize_t bytes_written;
 131
 132   bytes_written = write(ossfd, playing->buffer + playing->start,
 133                         bytes_to_play);
 134   if(bytes_written < 0)
 135     switch(errno) {
 136     case EINTR:                 /* interruped */
 137     case EAGAIN:                /* overrun */
 138       return 0;                 /* try again later */
 139     default:
 140       fatal(errno, "error writing to audio device");
 141     }
 142   return bytes_written / bpf;
 143 }
 144
 145 static int oss_slot;
 146
 147 /** @brief Fill in poll fd array for OSS */
 148 static void oss_beforepoll(int attribute((unused)) *timeoutp) {
 149   oss_slot = addfd(ossfd, POLLOUT|POLLERR);
 150 }
 151
 152 /** @brief Process poll() results for OSS */
 153 static int oss_ready(void) {
 154   return !!(fds[oss_slot].revents & (POLLOUT|POLLERR));
 155 }
 156
 157 const struct speaker_backend oss_backend = {
 158   BACKEND_OSS,
 159   0,
 160   oss_init,
 161   oss_activate,
 162   oss_play,
 163   oss_deactivate,
 164   oss_beforepoll,
 165   oss_ready
 166 };
 167
 168 #endif
 169
 170 /*
 171 Local Variables:
 172 c-basic-offset:2
 173 comment-column:40
 174 fill-column:79
 175 indent-tabs-mode:nil
 176 End:
 177 */