ALSA mixer support.

[disorder] / lib / mixer.h

diff --git a/lib/mixer.h b/lib/mixer.h
index 07aab5d21fb1dae517a604a95455d9b68945075d..6739ed82a31962d386235350192af68f7d9b2826 100644 (file)
--- a/lib/mixer.h
+++ b/lib/mixer.h
@@ -1,6 +1,6 @@
 /*
  * This file is part of DisOrder
- * Copyright (C) 2004 Richard Kettlewell
+ * 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
@@ -17,20 +17,47 @@
  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  * USA
  */
+/** @file lib/mixer.h
+ * @brief Mixer support
+ */
 
 #ifndef MIXER_H
 #define MIXER_H
 
-int mixer_channel(const char *c);
-/* convert @c@ to a channel number, or return -1 if it does not match */
+/** @brief Definition of a mixer */
+struct mixer {
+  /** @brief API used by this mixer */
+  int api;
+
+  /** @brief Get the volume
+   * @param left Where to store left-channel volume
+   * @param right Where to store right-channel volume
+   * @return 0 on success, non-0 on error
+   */
+  int (*get)(int *left, int *right);
+
+  /** @brief Set the volume
+   * @param left Pointer to target left-channel volume
+   * @param right Pointer to target right-channel volume
+   * @return 0 on success, non-0 on error
+   *
+   * @p left and @p right are updated with the actual volume set.
+   */
+  int (*set)(int *left, int *right);
+
+  /** @brief Default device */
+  const char *device;
+
+  /** @brief Default channel */
+  const char *channel;
+};
 
 int mixer_control(int *left, int *right, int set);
-/* get/set the current level.  If @set@ is true then the level is set
- * according to the pointers.  In either case the eventual level is
- * returned via the pointers.
- *
- * Returns 0 on success and -1 on error.
- */
+const char *mixer_default_device(int api);
+const char *mixer_default_channel(int api);
+
+extern const struct mixer mixer_oss;
+extern const struct mixer mixer_alsa;
 
 #endif /* MIXER_H */