aft: Avoid invalid read.

[paraslash.git] / mix.h

diff --git a/mix.h b/mix.h
index 305e9d80aaa1d742649fb77021b24fddc65c9b5d..cad435e811e09a9d3d924f946608fd57cce81ed1 100644 (file)
--- a/mix.h
+++ b/mix.h
@@ -1,10 +1,6 @@
-/*
- * Copyright (C) 2012-2014 Andre Noll <maan@tuebingen.mpg.de>
- *
- * Licensed under the GPL v2. For licencing details see COPYING.
- */
+/* Copyright (C) 2012 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
 
-/** \file mix.h Mixer API (used by para_fade). */
+/** \file mix.h Mixer API for para_mixer. */
 
 /**
  * Opaque structure which corresponds to an instance of a mixer.
@@ -16,10 +12,14 @@ struct mixer_handle;
 
 /**
  * Operations provided by each mixer plugin.
+ *
+ * Each mixer plugin must define a non-static instance of this structure, with
+ * all pointers initialized to non-NULL values. No other symbols need to be
+ * exported.
  */
 struct mixer {
-       /** Called on startup, must fill in all other members. */
-       void (*init)(struct mixer *self);
+       /** Used to identify the mixer. */
+       const char * const name;
        /** Return a handle that can be passed to other methods. */
        int (*open)(const char *dev, struct mixer_handle **handle);
        /** Returns a string of all valid mixer channels. */
@@ -34,3 +34,6 @@ struct mixer {
        /** Free all resources associated with the given handle. */
        void (*close)(struct mixer_handle **handle);
 };
+
+/** Declared even if unsupported because it does not hurt and avoids ifdefs. */
+extern const struct mixer alsa_mixer, oss_mixer;