Add B[Zlib]CompressionAlgorithm

* BCompressionAlgorithm is a base class for classes that provide
  compression/decompression functionality. There are methods for
  compressing/decompressing a single buffer and factory methods for
  a compressing/decompressing input/output BDataIO.
* BZlibCompressionAlgorithm is a BCompressionAlgorithm implementation
  using zlib.

headers/private/support/ZlibCompressionAlgorithm.h

@@ -0,0 +1,96 @@
+/*
+ * Copyright 2014, Ingo Weinhold, [email protected].
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef _ZLIB_COMPRESSION_ALGORITHM_H_
+#define _ZLIB_COMPRESSION_ALGORITHM_H_
+
+
+#include <CompressionAlgorithm.h>
+
+
+// compression level
+enum {
+	B_ZLIB_COMPRESSION_NONE		= 0,
+	B_ZLIB_COMPRESSION_FASTEST	= 1,
+	B_ZLIB_COMPRESSION_BEST		= 9,
+	B_ZLIB_COMPRESSION_DEFAULT	= -1,
+};
+
+
+class BZlibCompressionParameters : public BCompressionParameters {
+public:
+								BZlibCompressionParameters(
+									int compressionLevel
+										= B_ZLIB_COMPRESSION_DEFAULT);
+	virtual						~BZlibCompressionParameters();
+
+			int32				CompressionLevel() const;
+			void				SetCompressionLevel(int32 level);
+
+			size_t				BufferSize() const;
+			void				SetBufferSize(size_t size);
+
+private:
+			int32				fCompressionLevel;
+			size_t				fBufferSize;
+};
+
+
+class BZlibDecompressionParameters : public BDecompressionParameters {
+public:
+								BZlibDecompressionParameters();
+	virtual						~BZlibDecompressionParameters();
+
+			size_t				BufferSize() const;
+			void				SetBufferSize(size_t size);
+
+private:
+			size_t				fBufferSize;
+};
+
+
+class BZlibCompressionAlgorithm : public BCompressionAlgorithm {
+public:
+								BZlibCompressionAlgorithm();
+	virtual						~BZlibCompressionAlgorithm();
+
+	virtual	status_t			CreateCompressingInputStream(BDataIO* input,
+									const BCompressionParameters* parameters,
+									BDataIO*& _stream);
+	virtual	status_t			CreateCompressingOutputStream(BDataIO* output,
+									const BCompressionParameters* parameters,
+									BDataIO*& _stream);
+	virtual	status_t			CreateDecompressingInputStream(BDataIO* input,
+									const BDecompressionParameters* parameters,
+									BDataIO*& _stream);
+	virtual	status_t			CreateDecompressingOutputStream(BDataIO* output,
+									const BDecompressionParameters* parameters,
+									BDataIO*& _stream);
+
+	virtual	status_t			CompressBuffer(const void* input,
+									size_t inputSize, void* output,
+									size_t outputSize, size_t& _compressedSize,
+									const BCompressionParameters* parameters
+										= NULL);
+	virtual	status_t			DecompressBuffer(const void* input,
+									size_t inputSize, void* output,
+									size_t outputSize,
+									size_t& _uncompressedSize,
+									const BDecompressionParameters* parameters
+										= NULL);
+
+private:
+			struct CompressionStrategy;
+			struct DecompressionStrategy;
+
+			template<typename BaseClass, typename Strategy> struct Stream;
+			template<typename BaseClass, typename Strategy>
+				friend struct Stream;
+
+private:
+	static	status_t			_TranslateZlibError(int error);
+};
+
+
+#endif	// _ZLIB_COMPRESSION_ALGORITHM_H_