1 files changed, 339 insertions, 0 deletions
diff --git a/src/DecoderControl.hxx b/src/DecoderControl.hxx
new file mode 100644
index 000000000..42c28d785
--- /dev/null
+++ b/src/DecoderControl.hxx
@@ -0,0 +1,339 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * 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.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef MPD_DECODER_CONTROL_HXX
+#define MPD_DECODER_CONTROL_HXX
+
+#include "decoder_command.h"
+#include "audio_format.h"
+
+#include <glib.h>
+
+#include <assert.h>
+
+enum decoder_state {
+	DECODE_STATE_STOP = 0,
+	DECODE_STATE_START,
+	DECODE_STATE_DECODE,
+
+	/**
+	 * The last "START" command failed, because there was an I/O
+	 * error or because no decoder was able to decode the file.
+	 * This state will only come after START; once the state has
+	 * turned to DECODE, by definition no such error can occur.
+	 */
+	DECODE_STATE_ERROR,
+};
+
+struct decoder_control {
+	/** the handle of the decoder thread, or NULL if the decoder
+	    thread isn't running */
+	GThread *thread;
+
+	/**
+	 * This lock protects #state and #command.
+	 */
+	GMutex *mutex;
+
+	/**
+	 * Trigger this object after you have modified #command.  This
+	 * is also used by the decoder thread to notify the caller
+	 * when it has finished a command.
+	 */
+	GCond *cond;
+
+	/**
+	 * The trigger of this object's client.  It is signalled
+	 * whenever an event occurs.
+	 */
+	GCond *client_cond;
+
+	enum decoder_state state;
+	enum decoder_command command;
+
+	/**
+	 * The error that occurred in the decoder thread.  This
+	 * attribute is only valid if #state is #DECODE_STATE_ERROR.
+	 * The object must be freed when this object transitions to
+	 * any other state (usually #DECODE_STATE_START).
+	 */
+	GError *error;
+
+	bool quit;
+	bool seek_error;
+	bool seekable;
+	double seek_where;
+
+	/** the format of the song file */
+	struct audio_format in_audio_format;
+
+	/** the format being sent to the music pipe */
+	struct audio_format out_audio_format;
+
+	/**
+	 * The song currently being decoded.  This attribute is set by
+	 * the player thread, when it sends the #DECODE_COMMAND_START
+	 * command.
+	 *
+	 * This is a duplicate, and must be freed when this attribute
+	 * is cleared.
+	 */
+	struct song *song;
+
+	/**
+	 * The initial seek position (in milliseconds), e.g. to the
+	 * start of a sub-track described by a CUE file.
+	 *
+	 * This attribute is set by dc_start().
+	 */
+	unsigned start_ms;
+
+	/**
+	 * The decoder will stop when it reaches this position (in
+	 * milliseconds).  0 means don't stop before the end of the
+	 * file.
+	 *
+	 * This attribute is set by dc_start().
+	 */
+	unsigned end_ms;
+
+	float total_time;
+
+	/** the #music_chunk allocator */
+	struct music_buffer *buffer;
+
+	/**
+	 * The destination pipe for decoded chunks.  The caller thread
+	 * owns this object, and is responsible for freeing it.
+	 */
+	struct music_pipe *pipe;
+
+	float replay_gain_db;
+	float replay_gain_prev_db;
+	char *mixramp_start;
+	char *mixramp_end;
+	char *mixramp_prev_end;
+};
+
+G_GNUC_MALLOC
+struct decoder_control *
+dc_new();
+
+void
+dc_free(struct decoder_control *dc);
+
+/**
+ * Locks the #decoder_control object.
+ */
+static inline void
+decoder_lock(struct decoder_control *dc)
+{
+	g_mutex_lock(dc->mutex);
+}
+
+/**
+ * Unlocks the #decoder_control object.
+ */
+static inline void
+decoder_unlock(struct decoder_control *dc)
+{
+	g_mutex_unlock(dc->mutex);
+}
+
+/**
+ * Waits for a signal on the #decoder_control object.  This function
+ * is only valid in the decoder thread.  The object must be locked
+ * prior to calling this function.
+ */
+static inline void
+decoder_wait(struct decoder_control *dc)
+{
+	g_cond_wait(dc->cond, dc->mutex);
+}
+
+/**
+ * Signals the #decoder_control object.  This function is only valid
+ * in the player thread.  The object should be locked prior to calling
+ * this function.
+ */
+static inline void
+decoder_signal(struct decoder_control *dc)
+{
+	g_cond_signal(dc->cond);
+}
+
+static inline bool
+decoder_is_idle(const struct decoder_control *dc)
+{
+	return dc->state == DECODE_STATE_STOP ||
+		dc->state == DECODE_STATE_ERROR;
+}
+
+static inline bool
+decoder_is_starting(const struct decoder_control *dc)
+{
+	return dc->state == DECODE_STATE_START;
+}
+
+static inline bool
+decoder_has_failed(const struct decoder_control *dc)
+{
+	assert(dc->command == DECODE_COMMAND_NONE);
+
+	return dc->state == DECODE_STATE_ERROR;
+}
+
+/**
+ * Checks whether an error has occurred, and if so, returns a newly
+ * allocated copy of the #GError object.
+ *
+ * Caller must lock the object.
+ */
+static inline GError *
+dc_get_error(const struct decoder_control *dc)
+{
+	assert(dc != NULL);
+	assert(dc->command == DECODE_COMMAND_NONE);
+	assert(dc->state != DECODE_STATE_ERROR || dc->error != NULL);
+
+	return dc->state == DECODE_STATE_ERROR
+		? g_error_copy(dc->error)
+		: NULL;
+}
+
+/**
+ * Like dc_get_error(), but locks and unlocks the object.
+ */
+static inline GError *
+dc_lock_get_error(struct decoder_control *dc)
+{
+	decoder_lock(dc);
+	GError *error = dc_get_error(dc);
+	decoder_unlock(dc);
+	return error;
+}
+
+/**
+ * Clear the error condition and free the #GError object (if any).
+ *
+ * Caller must lock the object.
+ */
+static inline void
+dc_clear_error(struct decoder_control *dc)
+{
+	if (dc->state == DECODE_STATE_ERROR) {
+		g_error_free(dc->error);
+		dc->state = DECODE_STATE_STOP;
+	}
+}
+
+static inline bool
+decoder_lock_is_idle(struct decoder_control *dc)
+{
+	bool ret;
+
+	decoder_lock(dc);
+	ret = decoder_is_idle(dc);
+	decoder_unlock(dc);
+
+	return ret;
+}
+
+static inline bool
+decoder_lock_is_starting(struct decoder_control *dc)
+{
+	bool ret;
+
+	decoder_lock(dc);
+	ret = decoder_is_starting(dc);
+	decoder_unlock(dc);
+
+	return ret;
+}
+
+static inline bool
+decoder_lock_has_failed(struct decoder_control *dc)
+{
+	bool ret;
+
+	decoder_lock(dc);
+	ret = decoder_has_failed(dc);
+	decoder_unlock(dc);
+
+	return ret;
+}
+
+/**
+ * Check if the specified song is currently being decoded.  If the
+ * decoder is not running currently (or being started), then this
+ * function returns false in any case.
+ *
+ * Caller must lock the object.
+ */
+gcc_pure
+bool
+decoder_is_current_song(const struct decoder_control *dc,
+			const struct song *song);
+
+gcc_pure
+static inline bool
+decoder_lock_is_current_song(struct decoder_control *dc,
+			     const struct song *song)
+{
+	decoder_lock(dc);
+	const bool result = decoder_is_current_song(dc, song);
+	decoder_unlock(dc);
+	return result;
+}
+
+/**
+ * Start the decoder.
+ *
+ * @param the decoder
+ * @param song the song to be decoded; the given instance will be
+ * owned and freed by the decoder
+ * @param start_ms see #decoder_control
+ * @param end_ms see #decoder_control
+ * @param pipe the pipe which receives the decoded chunks (owned by
+ * the caller)
+ */
+void
+dc_start(struct decoder_control *dc, struct song *song,
+	 unsigned start_ms, unsigned end_ms,
+	 struct music_buffer *buffer, struct music_pipe *pipe);
+
+void
+dc_stop(struct decoder_control *dc);
+
+bool
+dc_seek(struct decoder_control *dc, double where);
+
+void
+dc_quit(struct decoder_control *dc);
+
+void
+dc_mixramp_start(struct decoder_control *dc, char *mixramp_start);
+
+void
+dc_mixramp_end(struct decoder_control *dc, char *mixramp_end);
+
+void
+dc_mixramp_prev_end(struct decoder_control *dc, char *mixramp_prev_end);
+
+#endif