Initial community commit

Src/external_dependencies/openmpt-trunk/include/ancient/src/RLENDecompressor.cpp

@@ -0,0 +1,62 @@
+/* Copyright (C) Teemu Suutari */
+
+#include "RLENDecompressor.hpp"
+#include "InputStream.hpp"
+#include "OutputStream.hpp"
+#include "common/Common.hpp"
+
+
+namespace ancient::internal
+{
+
+bool RLENDecompressor::detectHeaderXPK(uint32_t hdr) noexcept
+{
+	return hdr==FourCC("RLEN");
+}
+
+std::shared_ptr<XPKDecompressor> RLENDecompressor::create(uint32_t hdr,uint32_t recursionLevel,const Buffer &packedData,std::shared_ptr<XPKDecompressor::State> &state,bool verify)
+{
+	return std::make_shared<RLENDecompressor>(hdr,recursionLevel,packedData,state,verify);
+}
+
+RLENDecompressor::RLENDecompressor(uint32_t hdr,uint32_t recursionLevel,const Buffer &packedData,std::shared_ptr<XPKDecompressor::State> &state,bool verify) :
+	XPKDecompressor(recursionLevel),
+	_packedData(packedData)
+{
+	if (!detectHeaderXPK(hdr)) throw Decompressor::InvalidFormatError();
+}
+
+RLENDecompressor::~RLENDecompressor()
+{
+	// nothing needed
+}
+
+const std::string &RLENDecompressor::getSubName() const noexcept
+{
+	static std::string name="XPK-RLEN: RLE-compressor";
+	return name;
+}
+
+void RLENDecompressor::decompressImpl(Buffer &rawData,const Buffer &previousData,bool verify)
+{
+	ForwardInputStream inputStream(_packedData,0,_packedData.size());
+	ForwardOutputStream outputStream(rawData,0,rawData.size());
+
+	while (!outputStream.eof())
+	{
+		uint32_t count=uint32_t(inputStream.readByte());
+		if (count<128)
+		{
+			if (!count) throw Decompressor::DecompressionError();	// lets have this as error...
+			for (uint32_t i=0;i<count;i++) outputStream.writeByte(inputStream.readByte());
+		} else {
+			// I can see from different implementations that count=0x80 is buggy...
+			// lets try to have it more or less correctly here
+			count=256-count;
+			uint8_t ch=inputStream.readByte();
+			for (uint32_t i=0;i<count;i++) outputStream.writeByte(ch);
+		}
+	}
+}
+
+}