Unify sound API configuration.

[disorder] / lib / mixer-oss.c

diff --git a/lib/mixer-oss.c b/lib/mixer-oss.c
new file mode 100644 (file)
index 0000000..7ab73a2
--- /dev/null
+++ b/lib/mixer-oss.c
@@ -0,0 +1,165 @@
+/*
+ * This file is part of DisOrder
+ * Copyright (C) 2004, 2007 Richard Kettlewell
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+ * USA
+ */
+
+#include <config.h>
+#include "types.h"
+
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <stddef.h>
+#include <sys/ioctl.h>
+
+#include "configuration.h"
+#include "mixer.h"
+#include "log.h"
+#include "syscalls.h"
+
+#if HAVE_SYS_SOUNDCARD_H
+#include <sys/soundcard.h>
+
+/* documentation does not match implementation! */
+#ifndef SOUND_MIXER_READ
+# define SOUND_MIXER_READ(x) MIXER_READ(x)
+#endif
+#ifndef SOUND_MIXER_WRITE
+# define SOUND_MIXER_WRITE(x) MIXER_WRITE(x)
+#endif
+
+static const char *channels[] = SOUND_DEVICE_NAMES;
+
+static int mixer_channel(const char *c) {
+  unsigned n;
+  
+  if(!c[strspn(c, "0123456789")])
+    return atoi(c);
+  else {
+    for(n = 0; n < sizeof channels / sizeof *channels; ++n)
+      if(!strcmp(channels[n], c))
+       return n;
+    return -1;
+  }
+}
+
+static int oss_validate_channel(const char *c) {
+  if(mixer_channel(c) != -1)
+    return 1;
+  else
+    return 0;
+}
+
+static int oss_validate_device(const char *d) {
+  struct stat sb;
+
+  if(stat(d, &sb) < 0) {
+    error(errno, "%s", d);
+    return 0;
+  }
+  if(!S_ISCHR(sb.st_mode)) {
+    error(0, "%s: not a character device", d);
+    return 0;
+  }
+  return 1;
+}
+
+static int oss_do_open(void) {
+  int fd;
+  
+  if((fd = open(config->mixer, O_RDWR, 0)) < 0)
+    error(errno, "error opening %s", config->mixer);
+  return fd;
+}
+
+static int oss_do_get(int *left, int *right, int fd, int ch) {
+  int r;
+  
+  if(ioctl(fd, SOUND_MIXER_READ(ch), &r) == -1) {
+    error(errno, "error reading %s channel %s",
+         config->mixer, config->channel);
+    return -1;
+  }
+  *left = r & 0xff;
+  *right = (r >> 8) & 0xff;
+  return 0;
+}
+
+static int oss_get(int *left, int *right) {
+  int ch, fd;
+
+  if(config->mixer
+     && config->channel
+     && (ch = mixer_channel(config->channel)) != -1) {
+    if((fd = oss_do_open()) < 0)
+      return -1;
+    if(oss_do_get(left, right, fd, ch) < 0) {
+      xclose(fd);
+      return -1;
+    }
+    xclose(fd);
+    return 0;
+  } else
+    return -1;
+}
+
+static int oss_set(int *left, int *right) {
+  int ch, fd, r;
+
+  if(config->mixer
+     && config->channel
+     && (ch = mixer_channel(config->channel)) != -1) {
+    if((fd = oss_do_open()) < 0)
+      return -1;
+    r = (*left & 0xff) + (*right & 0xff) * 256;
+    if(ioctl(fd, SOUND_MIXER_WRITE(ch), &r) == -1) {
+      error(errno, "error changing %s channel %s",
+           config->mixer, config->channel);
+      xclose(fd);
+      return -1;
+    }
+    if(oss_do_get(left, right, fd, ch) < 0) {
+      xclose(fd);
+      return -1;
+    }
+    xclose(fd);
+    return 0;
+  } else
+    return -1;
+}
+
+const struct mixer mixer_oss = {
+  BACKEND_OSS,
+  oss_validate_device,
+  oss_validate_channel,
+  oss_get,
+  oss_set,
+  "/dev/mixer",
+  "pcm"
+};
+#endif
+
+/*
+Local Variables:
+c-basic-offset:2
+comment-column:40
+End:
+*/