Codec Kit: Initial BMetaData implementation

headers/os/codec/MetaData.h

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2018, Dario Casalinuovo. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+
+#ifndef _META_DATA_H
+#define _META_DATA_H
+
+#include <Message.h>
+
+
+namespace BPrivate {
+namespace media {
+
+
+enum MetaDataKeys {
+	// Playback capabilities
+	CanPause = 0x1000,	// bool
+	CanSeekBackward,	// bool
+	CanSeekForward,		// bool
+	CanSeek,			// bool
+
+	// Bitrates
+	AudioBitRate,		// uint32 (bps)
+	VideoBitRate,		// uint32 (bps)
+	AudioSampleRate,	// uint32 (hz)
+	VideoFrameRate,		// uint32 (hz)
+
+	// RFC2046 and RFC4281
+	MimeType,			// BString
+	AudioCodec,			// BString
+	VideoCodec,			// BString
+	VideoHeight,		// uint32
+	VideoWidth,			// uint32
+	NumTracks,			// uint32
+	DrmCrippled,		// bool
+
+	// General use attributes
+	Title,				// BString
+	Comment,			// BString
+	Copyright,			// BString
+	Album,				// BString
+	Artist,				// BString
+	Author,				// BString
+	Composer,			// BString
+	Genre,				// BString
+	// TODO: what we would use for encoded dates?
+	// Date,			// date
+	Duration,			// uint32 (ms)
+	Rating,				// BString
+	// TODO: BBitmap? uint8 array?
+	//AlbumArt,			// 
+	CDTrackNum,			// uint32
+	CDTrackMax			// uint32
+};
+
+
+class BMetaData {
+public:
+						BMetaData();
+						~BMetaData();
+
+	// Woah. It seems we need BValue there.
+	status_t			SetString(uint32 key, const BString& value);
+	status_t			SetBool(uint32 key, bool value);
+	status_t			SetUInt32(uint32 key, uint32 value);
+
+	status_t			FindString(uint32 key, BString* value) const;
+	status_t			FindBool(uint32 key, bool* value) const;
+    status_t			FindUInt32(uint32 key, uint32* value) const;
+
+	status_t			RemoveValue(uint32 key);
+
+	// Clean up all keys
+	void 				Reset();
+
+	status_t			FromMessage(const BMessage& msg);
+	const BMessage&		ToMessage();
+
+private:
+	// TODO: padding
+	BMessage*			fMessage;
+
+						BMetaData(const BMetaData&);
+						BMetaData& operator=(const BMetaData&);
+};
+
+} // namespace media
+} // namespace BPrivate
+
+using namespace BPrivate::media;
+
+#endif	// _META_DATA_H

src/kits/codec/Jamfile

@@ -17,6 +17,9 @@ for architectureObject in [ MultiArchSubDirSetup ] {
 			AdapterIO.cpp
 			MediaIO.cpp
 
+			# Support API
+			MetaData.cpp
+
 			# Codec Plugin API
 			ChunkCache.cpp
 			DecoderPlugin.cpp

src/kits/codec/MetaData.cpp

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2018, Dario Casalinuovo. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include <MetaData.h>
+#include <String.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+
+
+// TODO: probably we can do better
+const char*
+key_to_string(uint32 key)
+{
+	char buf[sizeof(char) * sizeof(uint32) * 4 + 1];
+	if (buf) {
+		sprintf(buf, "%"B_PRId32, key);
+	}
+	BString ret(buf);
+	ret.Prepend("codec:metadata:");
+	return ret.String();
+}
+
+
+BMetaData::BMetaData()
+	:
+	fMessage(NULL)
+{
+	fMessage = new BMessage();
+}
+
+
+BMetaData::~BMetaData()
+{
+	delete fMessage;
+}
+
+
+status_t
+BMetaData::SetString(uint32 key, const BString& value)
+{
+	return fMessage->AddString(key_to_string(key), value);
+}
+
+
+status_t
+BMetaData::SetBool(uint32 key, bool value)
+{
+	return fMessage->AddBool(key_to_string(key), value);
+}
+
+
+status_t
+BMetaData::SetUInt32(uint32 key, uint32 value)
+{
+	return fMessage->AddUInt32(key_to_string(key), value);
+}
+
+
+status_t
+BMetaData::FindString(uint32 key, BString* value) const
+{
+	return fMessage->FindString(key_to_string(key), value);
+}
+
+
+status_t
+BMetaData::FindBool(uint32 key, bool* value) const
+{
+	return fMessage->FindBool(key_to_string(key), value);
+}
+
+
+status_t
+BMetaData::FindUInt32(uint32 key, uint32* value) const
+{
+	return fMessage->FindUInt32(key_to_string(key), value);
+}
+
+
+status_t
+BMetaData::RemoveValue(uint32 key)
+{
+	return fMessage->RemoveName(key_to_string(key));
+}
+
+
+// Clean up all keys
+void
+BMetaData::Reset()
+{
+	delete fMessage;
+	fMessage = new BMessage();
+}