output: added output_api.h

Just like decoder_api.h, output_api.h provides the audio output API
which is used by the plugins.

src/output_api.h

@@ -0,0 +1,91 @@
+/* the Music Player Daemon (MPD)
+ * Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
+ * Copyright (C) 2008 Max Kellermann <max@duempel.org>
+ * This project's homepage is: http://www.musicpd.org
+ *
+ * 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
+ */
+
+#ifndef OUTPUT_API_H
+#define OUTPUT_API_H
+
+#include "../config.h"
+#include "pcm_utils.h"
+#include "audio_format.h"
+#include "tag.h"
+#include "conf.h"
+#include "log.h"
+#include "os_compat.h"
+
+#define DISABLED_AUDIO_OUTPUT_PLUGIN(plugin) AudioOutputPlugin plugin;
+
+typedef struct _AudioOutput AudioOutput;
+
+typedef int (*AudioOutputTestDefaultDeviceFunc) (void);
+
+typedef int (*AudioOutputInitDriverFunc) (AudioOutput * audioOutput,
+					  ConfigParam * param);
+
+typedef void (*AudioOutputFinishDriverFunc) (AudioOutput * audioOutput);
+
+typedef int (*AudioOutputOpenDeviceFunc) (AudioOutput * audioOutput);
+
+typedef int (*AudioOutputPlayFunc) (AudioOutput * audioOutput,
+				    const char *playChunk, size_t size);
+
+typedef void (*AudioOutputDropBufferedAudioFunc) (AudioOutput * audioOutput);
+
+typedef void (*AudioOutputCloseDeviceFunc) (AudioOutput * audioOutput);
+
+typedef void (*AudioOutputSendMetadataFunc) (AudioOutput * audioOutput,
+					     const struct tag *tag);
+
+typedef struct _AudioOutputPlugin {
+	const char *name;
+
+	AudioOutputTestDefaultDeviceFunc testDefaultDeviceFunc;
+	AudioOutputInitDriverFunc initDriverFunc;
+	AudioOutputFinishDriverFunc finishDriverFunc;
+	AudioOutputOpenDeviceFunc openDeviceFunc;
+	AudioOutputPlayFunc playFunc;
+	AudioOutputDropBufferedAudioFunc dropBufferedAudioFunc;
+	AudioOutputCloseDeviceFunc closeDeviceFunc;
+	AudioOutputSendMetadataFunc sendMetdataFunc;
+} AudioOutputPlugin;
+
+struct _AudioOutput {
+	int open;
+	const char *name;
+	const char *type;
+
+	AudioOutputFinishDriverFunc finishDriverFunc;
+	AudioOutputOpenDeviceFunc openDeviceFunc;
+	AudioOutputPlayFunc playFunc;
+	AudioOutputDropBufferedAudioFunc dropBufferedAudioFunc;
+	AudioOutputCloseDeviceFunc closeDeviceFunc;
+	AudioOutputSendMetadataFunc sendMetdataFunc;
+
+	int convertAudioFormat;
+	struct audio_format inAudioFormat;
+	struct audio_format outAudioFormat;
+	struct audio_format reqAudioFormat;
+	ConvState convState;
+	char *convBuffer;
+	size_t convBufferLen;
+	int sameInAndOutFormats;
+
+	void *data;
+};
+
+#endif