Initial community commit

Src/external_dependencies/openmpt-trunk/soundlib/ContainerPP20.cpp

@@ -0,0 +1,217 @@
+/*
+ * ContainerPP20.cpp
+ * -----------------
+ * Purpose: Handling of PowerPack PP20 compressed modules
+ * Notes  : (currently none)
+ * Authors: Olivier Lapicque
+ *          OpenMPT Devs
+ * The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
+ */
+
+
+#include "stdafx.h"
+
+#include "../common/FileReader.h"
+#include "Container.h"
+#include "Sndfile.h"
+
+#include <stdexcept>
+
+
+OPENMPT_NAMESPACE_BEGIN
+
+
+#if !defined(MPT_WITH_ANCIENT)
+
+
+struct PPBITBUFFER
+{
+	uint32 bitcount = 0;
+	uint32 bitbuffer = 0;
+	const uint8 *pStart = nullptr;
+	const uint8 *pSrc = nullptr;
+
+	uint32 GetBits(uint32 n);
+};
+
+
+uint32 PPBITBUFFER::GetBits(uint32 n)
+{
+	uint32 result = 0;
+
+	for(uint32 i = 0; i < n; i++)
+	{
+		if(!bitcount)
+		{
+			bitcount = 8;
+			if(pSrc != pStart)
+				pSrc--;
+			bitbuffer = *pSrc;
+		}
+		result = (result << 1) | (bitbuffer & 1);
+		bitbuffer >>= 1;
+		bitcount--;
+	}
+	return result;
+}
+
+
+static bool PP20_DoUnpack(const uint8 *pSrc, uint32 srcLen, uint8 *pDst, uint32 dstLen)
+{
+	const std::array<uint8, 4> modeTable{pSrc[0], pSrc[1], pSrc[2], pSrc[3]};
+	PPBITBUFFER BitBuffer;
+	BitBuffer.pStart = pSrc;
+	BitBuffer.pSrc = pSrc + srcLen - 4;
+	BitBuffer.GetBits(pSrc[srcLen - 1]);
+	uint32 bytesLeft = dstLen;
+	while(bytesLeft > 0)
+	{
+		if(!BitBuffer.GetBits(1))
+		{
+			uint32 count = 1, countAdd;
+			do
+			{
+				countAdd = BitBuffer.GetBits(2);
+				count += countAdd;
+			} while(countAdd == 3);
+			LimitMax(count, bytesLeft);
+			for(uint32 i = 0; i < count; i++)
+			{
+				pDst[--bytesLeft] = (uint8)BitBuffer.GetBits(8);
+			}
+			if(!bytesLeft)
+				break;
+		}
+		{
+			uint32 modeIndex = BitBuffer.GetBits(2);
+			MPT_CHECKER_ASSUME(modeIndex < 4);
+			uint32 count = modeIndex + 2, offset;
+			if(modeIndex == 3)
+			{
+				offset = BitBuffer.GetBits((BitBuffer.GetBits(1)) ? modeTable[modeIndex] : 7);
+				uint32 countAdd = 7;
+				do
+				{
+					countAdd = BitBuffer.GetBits(3);
+					count += countAdd;
+				} while(countAdd == 7);
+			} else
+			{
+				offset = BitBuffer.GetBits(modeTable[modeIndex]);
+			}
+			LimitMax(count, bytesLeft);
+			for(uint32 i = 0; i < count; i++)
+			{
+				pDst[bytesLeft - 1] = (bytesLeft + offset < dstLen) ? pDst[bytesLeft + offset] : 0;
+				--bytesLeft;
+			}
+		}
+	}
+	return true;
+}
+
+
+struct PP20header
+{
+	char  magic[4];       // "PP20"
+	uint8 efficiency[4];
+};
+
+MPT_BINARY_STRUCT(PP20header, 8)
+
+
+static bool ValidateHeader(const PP20header &hdr)
+{
+	if(std::memcmp(hdr.magic, "PP20", 4) != 0)
+	{
+		return false;
+	}
+	if(hdr.efficiency[0] < 9 || hdr.efficiency[0] > 15
+		|| hdr.efficiency[1] < 9 || hdr.efficiency[1] > 15
+		|| hdr.efficiency[2] < 9 || hdr.efficiency[2] > 15
+		|| hdr.efficiency[3] < 9 || hdr.efficiency[3] > 15)
+	{
+		return false;
+	}
+	return true;
+}
+
+
+CSoundFile::ProbeResult CSoundFile::ProbeFileHeaderPP20(MemoryFileReader file, const uint64 *pfilesize)
+{
+	PP20header hdr;
+	if(!file.ReadStruct(hdr))
+	{
+		return ProbeWantMoreData;
+	}
+	if(!ValidateHeader(hdr))
+	{
+		return ProbeFailure;
+	}
+	MPT_UNREFERENCED_PARAMETER(pfilesize);
+	return ProbeSuccess;
+}
+
+
+bool UnpackPP20(std::vector<ContainerItem> &containerItems, FileReader &file, ContainerLoadingFlags loadFlags)
+{
+	file.Rewind();
+	containerItems.clear();
+
+	PP20header hdr;
+	if(!file.ReadStruct(hdr))
+	{
+		return false;
+	}
+	if(!ValidateHeader(hdr))
+	{
+		return false;
+	}
+	if(loadFlags == ContainerOnlyVerifyHeader)
+	{
+		return true;
+	}
+
+	if(!file.CanRead(4))
+	{
+		return false;
+	}
+
+	containerItems.emplace_back();
+	containerItems.back().data_cache = std::make_unique<std::vector<char> >();
+	std::vector<char> & unpackedData = *(containerItems.back().data_cache);
+
+	FileReader::off_t length = file.GetLength();
+	if(!mpt::in_range<uint32>(length)) return false;
+	// Length word must be aligned
+	if((length % 2u) != 0)
+		return false;
+
+	file.Seek(length - 4);
+	uint32 dstLen = file.ReadUint24BE();
+	if(dstLen == 0)
+		return false;
+	try
+	{
+		unpackedData.resize(dstLen);
+	} catch(mpt::out_of_memory e)
+	{
+		mpt::delete_out_of_memory(e);
+		return false;
+	}
+	file.Seek(4);
+	bool result = PP20_DoUnpack(file.GetRawData<uint8>().data(), static_cast<uint32>(length - 4), mpt::byte_cast<uint8 *>(unpackedData.data()), dstLen);
+
+	if(result)
+	{
+		containerItems.back().file = FileReader(mpt::byte_cast<mpt::const_byte_span>(mpt::as_span(unpackedData)));
+	}
+
+	return result;
+}
+
+
+#endif // !MPT_WITH_ANCIENT
+
+
+OPENMPT_NAMESPACE_END