Add love.data module.

- Moved love.math.compress / decompress / decode / encode / hash to love.data.
- Changed love.data.compress/decompress to take the format argument first instead of second.
- Added love.data.newDataView. Returns a read-only subsection of an existing Data object.
- Added love.data.newByteData. Mostly useful in combination with LuaJIT's FFI as it has no extra methods currently.
- Added implementations of Lua 5.3's data packing APIs: love.data.packString / packData / unpack / getPackedSize.

Resolves issue #1336.
Resolves issue #1331.

--HG--
branch : minor

src/modules/data/CompressedData.h

@@ -0,0 +1,76 @@
+/**
+ * Copyright (c) 2006-2017 LOVE Development Team
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty.  In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ *
+ * 1. The origin of this software must not be misrepresented; you must not
+ *    claim that you wrote the original software. If you use this software
+ *    in a product, an acknowledgment in the product documentation would be
+ *    appreciated but is not required.
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ *    misrepresented as being the original software.
+ * 3. This notice may not be removed or altered from any source distribution.
+ **/
+
+#pragma once
+
+// LOVE
+#include "common/Data.h"
+#include "Compressor.h"
+
+namespace love
+{
+namespace data
+{
+
+/**
+ * Stores byte data compressed via DataModule::compress.
+ **/
+class CompressedData : public love::Data
+{
+public:
+
+	static love::Type type;
+
+	/**
+	 * Constructor just stores already-compressed data in the object.
+	 **/
+	CompressedData(Compressor::Format format, char *cdata, size_t compressedsize, size_t rawsize, bool own = true);
+	CompressedData(const CompressedData &c);
+	virtual ~CompressedData();
+
+	/**
+	 * Gets the format that was used to compress the data.
+	 **/
+	Compressor::Format getFormat() const;
+
+	/**
+	 * Gets the original (uncompressed) size of the compressed data. May return
+	 * 0 if the uncompressed size is unknown.
+	 **/
+	size_t getDecompressedSize() const;
+
+	// Implements Data.
+	CompressedData *clone() const override;
+	void *getData() const override;
+	size_t getSize() const override;
+
+private:
+
+	Compressor::Format format;
+
+	char *data;
+	size_t dataSize;
+
+	size_t originalSize;
+
+}; // CompressedData
+
+} // data
+} // love