icy_metadata: convert to C++

src/IcyMetaDataParser.hxx

@@ -0,0 +1,83 @@
+/*
+ * 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_ICY_META_DATA_PARSER_HXX
+#define MPD_ICY_META_DATA_PARSER_HXX
+
+#include <stddef.h>
+
+class IcyMetaDataParser {
+	size_t data_size, data_rest;
+
+	size_t meta_size, meta_position;
+	char *meta_data;
+
+	struct tag *tag;
+
+public:
+	IcyMetaDataParser():data_size(0) {}
+	~IcyMetaDataParser() {
+		Reset();
+	}
+
+	/**
+	 * Initialize an enabled icy_metadata object with the specified
+	 * data_size (from the icy-metaint HTTP response header).
+	 */
+	void Start(size_t _data_size) {
+		data_size = data_rest = _data_size;
+		meta_size = 0;
+		tag = nullptr;
+	}
+
+	/**
+	 * Resets the icy_metadata.  Call this after rewinding the stream.
+	 */
+	void Reset();
+
+	/**
+	 * Checks whether the icy_metadata object is enabled.
+	 */
+	bool IsDefined() const {
+		return data_size > 0;
+	}
+
+	/**
+	 * Evaluates data.  Returns the number of bytes of normal data which
+	 * can be read by the caller, but not more than "length".  If the
+	 * return value is smaller than "length", the caller should invoke
+	 * icy_meta().
+	 */
+	size_t Data(size_t length);
+
+	/**
+	 * Reads metadata from the stream.  Returns the number of bytes
+	 * consumed.  If the return value is smaller than "length", the caller
+	 * should invoke icy_data().
+	 */
+	size_t Meta(const void *data, size_t length);
+
+	struct tag *ReadTag() {
+		struct tag *result = tag;
+		tag = nullptr;
+		return result;
+	}
+};
+
+#endif