X-Git-Url: http://git.tuebingen.mpg.de/?a=blobdiff_plain;f=mix.h;fp=mix.h;h=a4105544daf526c857e86d9ff6a1ab2dab47cd9c;hb=46af7dd81149caee0409535d5d9884ed9fa5af0e;hp=0000000000000000000000000000000000000000;hpb=7024574d05fe8571c763d11c61626a9ac4980267;p=paraslash.git

diff --git a/mix.h b/mix.h
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index 00000000..a4105544
--- /dev/null
+++ b/mix.h
@@ -0,0 +1,28 @@
+/**
+ * Opaque structure which corresponds to an instance of a mixer.
+ *
+ * A pointer to a structure of this type is returned by ->open().  This pointer
+ * must be passed to most other methods of \ref struct mixer.
+ */
+struct mixer_handle;
+
+/**
+ * Operations provided by each mixer plugin.
+ */
+struct mixer {
+	/** Called on startup, must fill in all other members. */
+	void (*init)(struct mixer *self);
+	/** 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. */
+	char *(*get_channels)(struct mixer_handle *handle);
+	/** Select the channel for subsequent get/set operations. */
+	int (*set_channel)(struct mixer_handle *handle,
+		const char *mixer_channel);
+	/** Return the (normalized) current value of the selected channel. */
+	int (*get)(struct mixer_handle *handle);
+	/** Change the value of the selected channel. */
+	int (*set)(struct mixer_handle *handle, int val);
+	/** Free all ressources associated with the given handle. */
+	void (*close)(struct mixer_handle **handle);
+};