7 files changed, 706 insertions, 0 deletions
diff --git a/src/filter/chain_filter_plugin.c b/src/filter/chain_filter_plugin.c
new file mode 100644
index 000000000..ec8bef5c0
--- /dev/null
+++ b/src/filter/chain_filter_plugin.c
@@ -0,0 +1,177 @@
+/*
+ * Copyright (C) 2003-2009 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.
+ */
+
+#include "filter/chain_filter_plugin.h"
+#include "filter_plugin.h"
+#include "filter_internal.h"
+#include "filter_registry.h"
+
+#include <assert.h>
+
+struct filter_chain {
+	/** the base class */
+	struct filter base;
+
+	GSList *children;
+};
+
+static struct filter *
+chain_filter_init(G_GNUC_UNUSED const struct config_param *param,
+		  G_GNUC_UNUSED GError **error_r)
+{
+	struct filter_chain *chain = g_new(struct filter_chain, 1);
+
+	filter_init(&chain->base, &chain_filter_plugin);
+	chain->children = NULL;
+
+	return &chain->base;
+}
+
+static void
+chain_free_child(gpointer data, G_GNUC_UNUSED gpointer user_data)
+{
+	struct filter *filter = data;
+
+	filter_free(filter);
+}
+
+static void
+chain_filter_finish(struct filter *_filter)
+{
+	struct filter_chain *chain = (struct filter_chain *)_filter;
+
+	g_slist_foreach(chain->children, chain_free_child, NULL);
+	g_slist_free(chain->children);
+
+	g_free(chain);
+}
+
+/**
+ * Close all filters in the chain until #until is reached.  #until
+ * itself is not closed.
+ */
+static void
+chain_close_until(struct filter_chain *chain, const struct filter *until)
+{
+	GSList *i = chain->children;
+	struct filter *filter;
+
+	while (true) {
+		/* this assertion fails if #until does not exist
+		   (anymore) */
+		assert(i != NULL);
+
+		if (i->data == until)
+			/* don't close this filter */
+			break;
+
+		/* close this filter */
+		filter = i->data;
+		filter_close(filter);
+
+		i = g_slist_next(i);
+	}
+}
+
+static const struct audio_format *
+chain_filter_open(struct filter *_filter,
+		  const struct audio_format *audio_format,
+		  GError **error_r)
+{
+	struct filter_chain *chain = (struct filter_chain *)_filter;
+
+	for (GSList *i = chain->children; i != NULL; i = g_slist_next(i)) {
+		struct filter *filter = i->data;
+
+		audio_format = filter_open(filter, audio_format, error_r);
+		if (audio_format == NULL) {
+			/* rollback, close all children */
+			chain_close_until(chain, filter);
+			return NULL;
+		}
+	}
+
+	/* return the output format of the last filter */
+	return audio_format;
+}
+
+static void
+chain_close_child(gpointer data, G_GNUC_UNUSED gpointer user_data)
+{
+	struct filter *filter = data;
+
+	filter_close(filter);
+}
+
+static void
+chain_filter_close(struct filter *_filter)
+{
+	struct filter_chain *chain = (struct filter_chain *)_filter;
+
+	g_slist_foreach(chain->children, chain_close_child, NULL);
+}
+
+static const void *
+chain_filter_filter(struct filter *_filter,
+		    const void *src, size_t src_size,
+		    size_t *dest_size_r, GError **error_r)
+{
+	struct filter_chain *chain = (struct filter_chain *)_filter;
+
+	for (GSList *i = chain->children; i != NULL; i = g_slist_next(i)) {
+		struct filter *filter = i->data;
+
+		/* feed the output of the previous filter as input
+		   into the current one */
+		src = filter_filter(filter, src, src_size, &src_size, error_r);
+		if (src == NULL)
+			chain_close_until(chain, filter);
+	}
+
+	/* return the output of the last filter */
+	*dest_size_r = src_size;
+	return src;
+}
+
+const struct filter_plugin chain_filter_plugin = {
+	.name = "chain",
+	.init = chain_filter_init,
+	.finish = chain_filter_finish,
+	.open = chain_filter_open,
+	.close = chain_filter_close,
+	.filter = chain_filter_filter,
+};
+
+struct filter *
+filter_chain_new(void)
+{
+	struct filter *filter = filter_new(&chain_filter_plugin, NULL, NULL);
+	/* chain_filter_init() never fails */
+	assert(filter != NULL);
+
+	return filter;
+}
+
+void
+filter_chain_append(struct filter *_chain, struct filter *filter)
+{
+	struct filter_chain *chain = (struct filter_chain *)_chain;
+
+	chain->children = g_slist_append(chain->children, filter);
+}
diff --git a/src/filter/chain_filter_plugin.h b/src/filter/chain_filter_plugin.h
new file mode 100644
index 000000000..f8462b22d
--- /dev/null
+++ b/src/filter/chain_filter_plugin.h
@@ -0,0 +1,48 @@
+/*
+ * Copyright (C) 2003-2009 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.
+ */
+
+/** \file
+ *
+ * A filter chain is a container for several filters.  They are
+ * chained together, i.e. called in a row, one filter passing its
+ * output to the next one.
+ */
+
+#ifndef MPD_FILTER_CHAIN_H
+#define MPD_FILTER_CHAIN_H
+
+struct filter;
+
+/**
+ * Creates a new filter chain.
+ */
+struct filter *
+filter_chain_new(void);
+
+/**
+ * Appends a new filter at the end of the filter chain.  You must call
+ * this function before the first filter_open() call.
+ *
+ * @param chain the filter chain created with filter_chain_new()
+ * @param filter the filter to be appended to #chain
+ */
+void
+filter_chain_append(struct filter *chain, struct filter *filter);
+
+#endif
diff --git a/src/filter/convert_filter_plugin.c b/src/filter/convert_filter_plugin.c
new file mode 100644
index 000000000..d197dbdb9
--- /dev/null
+++ b/src/filter/convert_filter_plugin.c
@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2003-2009 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.
+ */
+
+#include "filter/convert_filter_plugin.h"
+#include "filter_plugin.h"
+#include "filter_internal.h"
+#include "filter_registry.h"
+#include "conf.h"
+#include "pcm_convert.h"
+#include "audio_format.h"
+#include "poison.h"
+
+#include <assert.h>
+#include <string.h>
+
+struct convert_filter {
+	struct filter base;
+
+	/**
+	 * The current convert, from 0 to #PCM_CONVERT_1.
+	 */
+	unsigned convert;
+
+	/**
+	 * The input audio format; PCM data is passed to the filter()
+	 * method in this format.
+	 */
+	struct audio_format in_audio_format;
+
+	/**
+	 * The output audio format; the consumer of this plugin
+	 * expects PCM data in this format.  This defaults to
+	 * #in_audio_format, and can be set with convert_filter_set().
+	 */
+	struct audio_format out_audio_format;
+
+	struct pcm_convert_state state;
+};
+
+static struct filter *
+convert_filter_init(G_GNUC_UNUSED const struct config_param *param,
+		    G_GNUC_UNUSED GError **error_r)
+{
+	struct convert_filter *filter = g_new(struct convert_filter, 1);
+
+	filter_init(&filter->base, &convert_filter_plugin);
+	return &filter->base;
+}
+
+static void
+convert_filter_finish(struct filter *filter)
+{
+	g_free(filter);
+}
+
+static const struct audio_format *
+convert_filter_open(struct filter *_filter,
+		    const struct audio_format *audio_format,
+		    G_GNUC_UNUSED GError **error_r)
+{
+	struct convert_filter *filter = (struct convert_filter *)_filter;
+
+	assert(audio_format_valid(audio_format));
+
+	filter->in_audio_format = filter->out_audio_format = *audio_format;
+	pcm_convert_init(&filter->state);
+
+	return audio_format;
+}
+
+static void
+convert_filter_close(struct filter *_filter)
+{
+	struct convert_filter *filter = (struct convert_filter *)_filter;
+
+	pcm_convert_deinit(&filter->state);
+
+	poison_undefined(&filter->in_audio_format,
+			 sizeof(filter->in_audio_format));
+	poison_undefined(&filter->out_audio_format,
+			 sizeof(filter->out_audio_format));
+}
+
+static const void *
+convert_filter_filter(struct filter *_filter, const void *src, size_t src_size,
+		     size_t *dest_size_r, GError **error_r)
+{
+	struct convert_filter *filter = (struct convert_filter *)_filter;
+	const void *dest;
+
+	if (audio_format_equals(&filter->in_audio_format,
+				&filter->out_audio_format)) {
+		/* optimized special case: no-op */
+		*dest_size_r = src_size;
+		return src;
+	}
+
+	dest = pcm_convert(&filter->state, &filter->in_audio_format,
+			   src, src_size,
+			   &filter->out_audio_format, dest_size_r,
+			   error_r);
+	if (dest == NULL)
+		return NULL;
+
+	return dest;
+}
+
+const struct filter_plugin convert_filter_plugin = {
+	.name = "convert",
+	.init = convert_filter_init,
+	.finish = convert_filter_finish,
+	.open = convert_filter_open,
+	.close = convert_filter_close,
+	.filter = convert_filter_filter,
+};
+
+void
+convert_filter_set(struct filter *_filter,
+		   const struct audio_format *out_audio_format)
+{
+	struct convert_filter *filter = (struct convert_filter *)_filter;
+
+	assert(filter != NULL);
+	assert(audio_format_valid(&filter->in_audio_format));
+	assert(audio_format_valid(&filter->out_audio_format));
+	assert(out_audio_format != NULL);
+	assert(audio_format_valid(out_audio_format));
+	assert(filter->in_audio_format.reverse_endian == 0);
+
+	filter->out_audio_format = *out_audio_format;
+}
diff --git a/src/filter/convert_filter_plugin.h b/src/filter/convert_filter_plugin.h
new file mode 100644
index 000000000..8d370b0cb
--- /dev/null
+++ b/src/filter/convert_filter_plugin.h
@@ -0,0 +1,36 @@
+/*
+ * Copyright (C) 2003-2009 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 CONVERT_FILTER_PLUGIN_H
+#define CONVERT_FILTER_PLUGIN_H
+
+struct filter;
+struct audio_format;
+
+/**
+ * Sets the output audio format for the specified filter.  You must
+ * call this after the filter has been opened.  Since this audio
+ * format switch is a violation of the filter API, this filter must be
+ * the last in a chain.
+ */
+void
+convert_filter_set(struct filter *filter,
+		   const struct audio_format *out_audio_format);
+
+#endif
diff --git a/src/filter/null_filter_plugin.c b/src/filter/null_filter_plugin.c
new file mode 100644
index 000000000..689388558
--- /dev/null
+++ b/src/filter/null_filter_plugin.c
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2003-2009 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.
+ */
+
+/** \file
+ *
+ * This filter plugin does nothing.  That is not quite useful, except
+ * for testing the filter core, or as a template for new filter
+ * plugins.
+ */
+
+#include "filter_plugin.h"
+#include "filter_internal.h"
+#include "filter_registry.h"
+
+#include <assert.h>
+
+struct null_filter {
+	struct filter filter;
+};
+
+static struct filter *
+null_filter_init(G_GNUC_UNUSED const struct config_param *param,
+		 G_GNUC_UNUSED GError **error_r)
+{
+	struct null_filter *filter = g_new(struct null_filter, 1);
+
+	filter_init(&filter->filter, &null_filter_plugin);
+	return &filter->filter;
+}
+
+static void
+null_filter_finish(struct filter *_filter)
+{
+	struct null_filter *filter = (struct null_filter *)_filter;
+
+	g_free(filter);
+}
+
+static const struct audio_format *
+null_filter_open(struct filter *_filter,
+		 const struct audio_format *audio_format,
+		 G_GNUC_UNUSED GError **error_r)
+{
+	struct null_filter *filter = (struct null_filter *)_filter;
+	(void)filter;
+
+	return audio_format;
+}
+
+static void
+null_filter_close(struct filter *_filter)
+{
+	struct null_filter *filter = (struct null_filter *)_filter;
+	(void)filter;
+}
+
+static const void *
+null_filter_filter(struct filter *_filter,
+		   const void *src, size_t src_size,
+		   size_t *dest_size_r, G_GNUC_UNUSED GError **error_r)
+{
+	struct null_filter *filter = (struct null_filter *)_filter;
+	(void)filter;
+
+	/* return the unmodified source buffer */
+	*dest_size_r = src_size;
+	return src;
+}
+
+const struct filter_plugin null_filter_plugin = {
+	.name = "null",
+	.init = null_filter_init,
+	.finish = null_filter_finish,
+	.open = null_filter_open,
+	.close = null_filter_close,
+	.filter = null_filter_filter,
+};
diff --git a/src/filter/volume_filter_plugin.c b/src/filter/volume_filter_plugin.c
new file mode 100644
index 000000000..298ca2f36
--- /dev/null
+++ b/src/filter/volume_filter_plugin.c
@@ -0,0 +1,174 @@
+/*
+ * Copyright (C) 2003-2009 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.
+ */
+
+#include "filter/volume_filter_plugin.h"
+#include "filter_plugin.h"
+#include "filter_internal.h"
+#include "filter_registry.h"
+#include "conf.h"
+#include "pcm_buffer.h"
+#include "pcm_volume.h"
+#include "audio_format.h"
+#include "player_control.h"
+
+#include <assert.h>
+#include <string.h>
+
+struct volume_filter {
+	struct filter filter;
+
+	/**
+	 * The current volume, from 0 to #PCM_VOLUME_1.
+	 */
+	unsigned volume;
+
+	struct audio_format audio_format;
+
+	struct pcm_buffer buffer;
+};
+
+static inline GQuark
+volume_quark(void)
+{
+	return g_quark_from_static_string("pcm_volume");
+}
+
+static struct filter *
+volume_filter_init(G_GNUC_UNUSED const struct config_param *param,
+		   G_GNUC_UNUSED GError **error_r)
+{
+	struct volume_filter *filter = g_new(struct volume_filter, 1);
+
+	filter_init(&filter->filter, &volume_filter_plugin);
+	filter->volume = PCM_VOLUME_1;
+
+	return &filter->filter;
+}
+
+static void
+volume_filter_finish(struct filter *filter)
+{
+	g_free(filter);
+}
+
+static const struct audio_format *
+volume_filter_open(struct filter *_filter,
+		   const struct audio_format *audio_format,
+		   GError **error_r)
+{
+	struct volume_filter *filter = (struct volume_filter *)_filter;
+
+	if (audio_format->bits != 8 && audio_format->bits != 16 &&
+	    audio_format->bits != 24) {
+		g_set_error(error_r, volume_quark(), 0,
+			    "Unsupported audio format");
+		return false;
+	}
+
+	if (audio_format->reverse_endian) {
+		g_set_error(error_r, volume_quark(), 0,
+			    "Software volume for reverse endian "
+			    "samples is not implemented");
+		return false;
+	}
+
+	filter->audio_format = *audio_format;
+	pcm_buffer_init(&filter->buffer);
+
+	return &filter->audio_format;
+}
+
+static void
+volume_filter_close(struct filter *_filter)
+{
+	struct volume_filter *filter = (struct volume_filter *)_filter;
+
+	pcm_buffer_deinit(&filter->buffer);
+}
+
+static const void *
+volume_filter_filter(struct filter *_filter, const void *src, size_t src_size,
+		     size_t *dest_size_r, GError **error_r)
+{
+	struct volume_filter *filter = (struct volume_filter *)_filter;
+	bool success;
+	void *dest;
+
+	if (filter->volume >= PCM_VOLUME_1) {
+		/* optimized special case: 100% volume = no-op */
+		*dest_size_r = src_size;
+		return src;
+	}
+
+	dest = pcm_buffer_get(&filter->buffer, src_size);
+	*dest_size_r = src_size;
+
+	if (filter->volume <= 0) {
+		/* optimized special case: 0% volume = memset(0) */
+		/* XXX is this valid for all sample formats? What
+		   about floating point? */
+		memset(dest, 0, src_size);
+		return dest;
+	}
+
+	memcpy(dest, src, src_size);
+
+	success = pcm_volume(dest, src_size, &filter->audio_format,
+			     filter->volume);
+	if (!success) {
+		g_set_error(error_r, volume_quark(), 0,
+			    "pcm_volume() has failed");
+		return NULL;
+	}
+
+	return dest;
+}
+
+const struct filter_plugin volume_filter_plugin = {
+	.name = "volume",
+	.init = volume_filter_init,
+	.finish = volume_filter_finish,
+	.open = volume_filter_open,
+	.close = volume_filter_close,
+	.filter = volume_filter_filter,
+};
+
+unsigned
+volume_filter_get(const struct filter *_filter)
+{
+	const struct volume_filter *filter =
+		(const struct volume_filter *)_filter;
+
+	assert(filter->filter.plugin == &volume_filter_plugin);
+	assert(filter->volume <= PCM_VOLUME_1);
+
+	return filter->volume;
+}
+
+void
+volume_filter_set(struct filter *_filter, unsigned volume)
+{
+	struct volume_filter *filter = (struct volume_filter *)_filter;
+
+	assert(filter->filter.plugin == &volume_filter_plugin);
+	assert(volume <= PCM_VOLUME_1);
+
+	filter->volume = volume;
+}
+
diff --git a/src/filter/volume_filter_plugin.h b/src/filter/volume_filter_plugin.h
new file mode 100644
index 000000000..c064741a2
--- /dev/null
+++ b/src/filter/volume_filter_plugin.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2003-2009 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 VOLUME_FILTER_PLUGIN_H
+#define VOLUME_FILTER_PLUGIN_H
+
+struct filter;
+
+unsigned
+volume_filter_get(const struct filter *filter);
+
+void
+volume_filter_set(struct filter *filter, unsigned volume);
+
+#endif