pcm_export: convert to C++

3 files changed, 198 insertions, 226 deletions

diff --git a/src/pcm/PcmExport.cxx b/src/pcm/PcmExport.cxx
new file mode 100644
index 000000000..288b59ab4
--- /dev/null
+++ b/src/pcm/PcmExport.cxx
@@ -0,0 +1,148 @@
+/*
+ * 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.
+ */
+
+#include "config.h"
+#include "PcmExport.hxx"
+
+extern "C" {
+#include "pcm_dsd_usb.h"
+#include "pcm_pack.h"
+#include "util/byte_reverse.h"
+}
+
+void
+PcmExport::Open(enum sample_format sample_format, unsigned _channels,
+		bool _dsd_usb, bool _shift8, bool _pack, bool _reverse_endian)
+{
+	assert(audio_valid_sample_format(sample_format));
+	assert(!_dsd_usb || audio_valid_channel_count(_channels));
+
+	channels = _channels;
+	dsd_usb = _dsd_usb && sample_format == SAMPLE_FORMAT_DSD;
+	if (dsd_usb)
+		/* after the conversion to DSD-over-USB, the DSD
+		   samples are stuffed inside fake 24 bit samples */
+		sample_format = SAMPLE_FORMAT_S24_P32;
+
+	shift8 = _shift8 && sample_format == SAMPLE_FORMAT_S24_P32;
+	pack24 = _pack && sample_format == SAMPLE_FORMAT_S24_P32;
+
+	assert(!shift8 || !pack24);
+
+	reverse_endian = 0;
+	if (_reverse_endian) {
+		size_t sample_size = pack24
+			? 3
+			: sample_format_size(sample_format);
+		assert(sample_size <= 0xff);
+
+		if (sample_size > 1)
+			reverse_endian = sample_size;
+	}
+}
+
+size_t
+PcmExport::GetFrameSize(const struct audio_format &audio_format) const
+{
+	if (pack24)
+		/* packed 24 bit samples (3 bytes per sample) */
+		return audio_format.channels * 3;
+
+	if (dsd_usb)
+		/* the DSD-over-USB draft says that DSD 1-bit samples
+		   are enclosed within 24 bit samples, and MPD's
+		   representation of 24 bit is padded to 32 bit (4
+		   bytes per sample) */
+		return channels * 4;
+
+	return audio_format_frame_size(&audio_format);
+}
+
+const void *
+PcmExport::Export(const void *data, size_t size, size_t &dest_size_r)
+{
+	if (dsd_usb)
+		data = pcm_dsd_to_usb(&dsd_buffer, channels,
+				      (const uint8_t *)data, size, &size);
+
+	if (pack24) {
+		assert(size % 4 == 0);
+
+		const size_t num_samples = size / 4;
+		const size_t dest_size = num_samples * 3;
+
+		const uint8_t *src8 = (const uint8_t *)data;
+		const uint8_t *src_end8 = src8 + size;
+		uint8_t *dest = (uint8_t *)
+			pcm_buffer_get(&pack_buffer, dest_size);
+		assert(dest != NULL);
+
+		pcm_pack_24(dest, (const int32_t *)src8,
+			    (const int32_t *)src_end8);
+
+		data = dest;
+		size = dest_size;
+	} else if (shift8) {
+		assert(size % 4 == 0);
+
+		const uint8_t *src8 = (const uint8_t *)data;
+		const uint8_t *src_end8 = src8 + size;
+		const uint32_t *src = (const uint32_t *)src8;
+		const uint32_t *const src_end = (const uint32_t *)src_end8;
+
+		uint32_t *dest = (uint32_t *)
+			pcm_buffer_get(&pack_buffer, size);
+		data = dest;
+
+		while (src < src_end)
+			*dest++ = *src++ << 8;
+	}
+
+
+	if (reverse_endian > 0) {
+		assert(reverse_endian >= 2);
+
+		uint8_t *dest = (uint8_t *)
+			pcm_buffer_get(&reverse_buffer, size);
+		assert(dest != NULL);
+
+		const uint8_t *src = (const uint8_t *)data;
+		const uint8_t *src_end = src + size;
+		reverse_bytes(dest, src, src_end, reverse_endian);
+
+		data = dest;
+	}
+
+	dest_size_r = size;
+	return data;
+}
+
+size_t
+PcmExport::CalcSourceSize(size_t size) const
+{
+	if (pack24)
+		/* 32 bit to 24 bit conversion (4 to 3 bytes) */
+		size = (size / 3) * 4;
+
+	if (dsd_usb)
+		/* DSD over USB doubles the transport size */
+		size /= 2;
+
+	return size;
+}
diff --git a/src/pcm/pcm_export.h b/src/pcm/PcmExport.hxx
index 005db48e0..4fb5cc9fc 100644
--- a/src/pcm/pcm_export.h
+++ b/src/pcm/PcmExport.hxx
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2003-2012 The Music Player Daemon Project
+ * 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
@@ -17,15 +17,13 @@
  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#ifndef PCM_EXPORT_H
-#define PCM_EXPORT_H
+#ifndef PCM_EXPORT_HXX
+#define PCM_EXPORT_HXX
 
 #include "check.h"
 #include "pcm_buffer.h"
 #include "audio_format.h"
 
-#include <stdbool.h>
-
 struct audio_format;
 
 /**
@@ -33,7 +31,7 @@ struct audio_format;
  * outside of MPD.  It has a few more options to tweak the binary
  * representation which are not supported by the pcm_convert library.
  */
-struct pcm_export_state {
+struct PcmExport {
 	/**
 	 * The buffer is used to convert DSD samples to the
 	 * DSD-over-USB format.
@@ -85,71 +83,57 @@ struct pcm_export_state {
 	 * sample (2 or bigger).
 	 */
 	uint8_t reverse_endian;
-};
 
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-/**
- * Initialize a #pcm_export_state object.
- */
-void
-pcm_export_init(struct pcm_export_state *state);
-
-/**
- * Deinitialize a #pcm_export_state object and free allocated memory.
- */
-void
-pcm_export_deinit(struct pcm_export_state *state);
+	PcmExport() {
+		pcm_buffer_init(&reverse_buffer);
+		pcm_buffer_init(&pack_buffer);
+		pcm_buffer_init(&dsd_buffer);
+	}
 
-/**
- * Open the #pcm_export_state object.
- *
- * There is no "close" method.  This function may be called multiple
- * times to reuse the object, until pcm_export_deinit() is called.
- *
- * This function cannot fail.
- *
- * @param channels the number of channels; ignored unless dsd_usb is set
- */
-void
-pcm_export_open(struct pcm_export_state *state,
-		enum sample_format sample_format, unsigned channels,
-		bool dsd_usb, bool shift8, bool pack, bool reverse_endian);
+	~PcmExport() {
+		pcm_buffer_deinit(&reverse_buffer);
+		pcm_buffer_deinit(&pack_buffer);
+		pcm_buffer_deinit(&dsd_buffer);
+	}
 
-/**
- * Calculate the size of one output frame.
- */
-G_GNUC_PURE
-size_t
-pcm_export_frame_size(const struct pcm_export_state *state,
-		      const struct audio_format *audio_format);
+	/**
+	 * Open the #pcm_export_state object.
+	 *
+	 * There is no "close" method.  This function may be called multiple
+	 * times to reuse the object, until pcm_export_deinit() is called.
+	 *
+	 * This function cannot fail.
+	 *
+	 * @param channels the number of channels; ignored unless dsd_usb is set
+	 */
+	void Open(enum sample_format sample_format, unsigned channels,
+		  bool dsd_usb, bool shift8, bool pack, bool reverse_endian);
 
-/**
- * Export a PCM buffer.
- *
- * @param state an initialized and open pcm_export_state object
- * @param src the source PCM buffer
- * @param src_size the size of #src in bytes
- * @param dest_size_r returns the number of bytes of the destination buffer
- * @return the destination buffer (may be a pointer to the source buffer)
- */
-const void *
-pcm_export(struct pcm_export_state *state, const void *src, size_t src_size,
-	   size_t *dest_size_r);
+	/**
+	 * Calculate the size of one output frame.
+	 */
+	gcc_pure
+	size_t GetFrameSize(const struct audio_format &audio_format) const;
 
-/**
- * Converts the number of consumed bytes from the pcm_export()
- * destination buffer to the according number of bytes from the
- * pcm_export() source buffer.
- */
-G_GNUC_PURE
-size_t
-pcm_export_source_size(const struct pcm_export_state *state, size_t dest_size);
+	/**
+	 * Export a PCM buffer.
+	 *
+	 * @param state an initialized and open pcm_export_state object
+	 * @param src the source PCM buffer
+	 * @param src_size the size of #src in bytes
+	 * @param dest_size_r returns the number of bytes of the destination buffer
+	 * @return the destination buffer (may be a pointer to the source buffer)
+	 */
+	const void *Export(const void *src, size_t src_size,
+			   size_t &dest_size_r);
 
-#ifdef __cplusplus
-}
-#endif
+	/**
+	 * Converts the number of consumed bytes from the pcm_export()
+	 * destination buffer to the according number of bytes from the
+	 * pcm_export() source buffer.
+	 */
+	gcc_pure
+	size_t CalcSourceSize(size_t dest_size) const;
+};
 
 #endif
diff --git a/src/pcm/pcm_export.c b/src/pcm/pcm_export.c
deleted file mode 100644
index 144ac71cd..000000000
--- a/src/pcm/pcm_export.c
+++ /dev/null
@@ -1,160 +0,0 @@
-/*
- * Copyright (C) 2003-2012 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 "config.h"
-#include "pcm_export.h"
-#include "pcm_dsd_usb.h"
-#include "pcm_pack.h"
-#include "util/byte_reverse.h"
-
-void
-pcm_export_init(struct pcm_export_state *state)
-{
-	pcm_buffer_init(&state->reverse_buffer);
-	pcm_buffer_init(&state->pack_buffer);
-	pcm_buffer_init(&state->dsd_buffer);
-}
-
-void pcm_export_deinit(struct pcm_export_state *state)
-{
-	pcm_buffer_deinit(&state->reverse_buffer);
-	pcm_buffer_deinit(&state->pack_buffer);
-	pcm_buffer_deinit(&state->dsd_buffer);
-}
-
-void
-pcm_export_open(struct pcm_export_state *state,
-		enum sample_format sample_format, unsigned channels,
-		bool dsd_usb, bool shift8, bool pack, bool reverse_endian)
-{
-	assert(audio_valid_sample_format(sample_format));
-	assert(!dsd_usb || audio_valid_channel_count(channels));
-
-	state->channels = channels;
-	state->dsd_usb = dsd_usb && sample_format == SAMPLE_FORMAT_DSD;
-	if (state->dsd_usb)
-		/* after the conversion to DSD-over-USB, the DSD
-		   samples are stuffed inside fake 24 bit samples */
-		sample_format = SAMPLE_FORMAT_S24_P32;
-
-	state->shift8 = shift8 && sample_format == SAMPLE_FORMAT_S24_P32;
-	state->pack24 = pack && sample_format == SAMPLE_FORMAT_S24_P32;
-
-	assert(!state->shift8 || !state->pack24);
-
-	state->reverse_endian = 0;
-	if (reverse_endian) {
-		size_t sample_size = state->pack24
-			? 3
-			: sample_format_size(sample_format);
-		assert(sample_size <= 0xff);
-
-		if (sample_size > 1)
-			state->reverse_endian = sample_size;
-	}
-}
-
-size_t
-pcm_export_frame_size(const struct pcm_export_state *state,
-		      const struct audio_format *audio_format)
-{
-	assert(state != NULL);
-	assert(audio_format != NULL);
-
-	if (state->pack24)
-		/* packed 24 bit samples (3 bytes per sample) */
-		return audio_format->channels * 3;
-
-	if (state->dsd_usb)
-		/* the DSD-over-USB draft says that DSD 1-bit samples
-		   are enclosed within 24 bit samples, and MPD's
-		   representation of 24 bit is padded to 32 bit (4
-		   bytes per sample) */
-		return audio_format->channels * 4;
-
-	return audio_format_frame_size(audio_format);
-}
-
-const void *
-pcm_export(struct pcm_export_state *state, const void *data, size_t size,
-	   size_t *dest_size_r)
-{
-	if (state->dsd_usb)
-		data = pcm_dsd_to_usb(&state->dsd_buffer, state->channels,
-				      data, size, &size);
-
-	if (state->pack24) {
-		assert(size % 4 == 0);
-
-		const size_t num_samples = size / 4;
-		const size_t dest_size = num_samples * 3;
-
-		const uint8_t *src8 = data, *src_end8 = src8 + size;
-		uint8_t *dest = pcm_buffer_get(&state->pack_buffer, dest_size);
-		assert(dest != NULL);
-
-		pcm_pack_24(dest, (const int32_t *)src8,
-			    (const int32_t *)src_end8);
-
-		data = dest;
-		size = dest_size;
-	} else if (state->shift8) {
-		assert(size % 4 == 0);
-
-		const uint8_t *src8 = data, *src_end8 = src8 + size;
-		const uint32_t *src = (const uint32_t *)src8;
-		const uint32_t *const src_end = (const uint32_t *)src_end8;
-
-		uint32_t *dest = pcm_buffer_get(&state->pack_buffer, size);
-		data = dest;
-
-		while (src < src_end)
-			*dest++ = *src++ << 8;
-	}
-
-
-	if (state->reverse_endian > 0) {
-		assert(state->reverse_endian >= 2);
-
-		void *dest = pcm_buffer_get(&state->reverse_buffer, size);
-		assert(dest != NULL);
-
-		const uint8_t *src = data, *src_end = src + size;
-		reverse_bytes(dest, src, src_end, state->reverse_endian);
-
-		data = dest;
-	}
-
-	*dest_size_r = size;
-	return data;
-}
-
-size_t
-pcm_export_source_size(const struct pcm_export_state *state, size_t size)
-{
-	if (state->pack24)
-		/* 32 bit to 24 bit conversion (4 to 3 bytes) */
-		size = (size / 3) * 4;
-
-	if (state->dsd_usb)
-		/* DSD over USB doubles the transport size */
-		size /= 2;
-
-	return size;
-}