1251607Sdim//===--- Compression.cpp - Compression implementation ---------------------===// 2251607Sdim// 3251607Sdim// The LLVM Compiler Infrastructure 4251607Sdim// 5251607Sdim// This file is distributed under the University of Illinois Open Source 6251607Sdim// License. See LICENSE.TXT for details. 7251607Sdim// 8251607Sdim//===----------------------------------------------------------------------===// 9251607Sdim// 10251607Sdim// This file implements compression functions. 11251607Sdim// 12251607Sdim//===----------------------------------------------------------------------===// 13251607Sdim 14251607Sdim#include "llvm/Support/Compression.h" 15251607Sdim#include "llvm/ADT/OwningPtr.h" 16251607Sdim#include "llvm/ADT/StringRef.h" 17251607Sdim#include "llvm/Config/config.h" 18251607Sdim#include "llvm/Support/Compiler.h" 19251607Sdim#include "llvm/Support/ErrorHandling.h" 20251607Sdim#include "llvm/Support/MemoryBuffer.h" 21251607Sdim#if LLVM_ENABLE_ZLIB == 1 && HAVE_ZLIB_H 22251607Sdim#include <zlib.h> 23251607Sdim#endif 24251607Sdim 25251607Sdimusing namespace llvm; 26251607Sdim 27251607Sdim#if LLVM_ENABLE_ZLIB == 1 && HAVE_LIBZ 28251607Sdimstatic int encodeZlibCompressionLevel(zlib::CompressionLevel Level) { 29251607Sdim switch (Level) { 30251607Sdim case zlib::NoCompression: return 0; 31251607Sdim case zlib::BestSpeedCompression: return 1; 32251607Sdim case zlib::DefaultCompression: return Z_DEFAULT_COMPRESSION; 33251607Sdim case zlib::BestSizeCompression: return 9; 34251607Sdim } 35251607Sdim llvm_unreachable("Invalid zlib::CompressionLevel!"); 36251607Sdim} 37251607Sdim 38251607Sdimstatic zlib::Status encodeZlibReturnValue(int ReturnValue) { 39251607Sdim switch (ReturnValue) { 40251607Sdim case Z_OK: return zlib::StatusOK; 41251607Sdim case Z_MEM_ERROR: return zlib::StatusOutOfMemory; 42251607Sdim case Z_BUF_ERROR: return zlib::StatusBufferTooShort; 43251607Sdim case Z_STREAM_ERROR: return zlib::StatusInvalidArg; 44251607Sdim case Z_DATA_ERROR: return zlib::StatusInvalidData; 45251607Sdim default: llvm_unreachable("unknown zlib return status!"); 46251607Sdim } 47251607Sdim} 48251607Sdim 49251607Sdimbool zlib::isAvailable() { return true; } 50251607Sdimzlib::Status zlib::compress(StringRef InputBuffer, 51251607Sdim OwningPtr<MemoryBuffer> &CompressedBuffer, 52251607Sdim CompressionLevel Level) { 53251607Sdim unsigned long CompressedSize = ::compressBound(InputBuffer.size()); 54251607Sdim OwningArrayPtr<char> TmpBuffer(new char[CompressedSize]); 55251607Sdim int CLevel = encodeZlibCompressionLevel(Level); 56251607Sdim Status Res = encodeZlibReturnValue(::compress2( 57251607Sdim (Bytef *)TmpBuffer.get(), &CompressedSize, 58251607Sdim (const Bytef *)InputBuffer.data(), InputBuffer.size(), CLevel)); 59251607Sdim if (Res == StatusOK) { 60251607Sdim CompressedBuffer.reset(MemoryBuffer::getMemBufferCopy( 61251607Sdim StringRef(TmpBuffer.get(), CompressedSize))); 62251607Sdim // Tell MSan that memory initialized by zlib is valid. 63251607Sdim __msan_unpoison(CompressedBuffer->getBufferStart(), CompressedSize); 64251607Sdim } 65251607Sdim return Res; 66251607Sdim} 67251607Sdim 68251607Sdimzlib::Status zlib::uncompress(StringRef InputBuffer, 69251607Sdim OwningPtr<MemoryBuffer> &UncompressedBuffer, 70251607Sdim size_t UncompressedSize) { 71251607Sdim OwningArrayPtr<char> TmpBuffer(new char[UncompressedSize]); 72251607Sdim Status Res = encodeZlibReturnValue( 73251607Sdim ::uncompress((Bytef *)TmpBuffer.get(), (uLongf *)&UncompressedSize, 74251607Sdim (const Bytef *)InputBuffer.data(), InputBuffer.size())); 75251607Sdim if (Res == StatusOK) { 76251607Sdim UncompressedBuffer.reset(MemoryBuffer::getMemBufferCopy( 77251607Sdim StringRef(TmpBuffer.get(), UncompressedSize))); 78251607Sdim // Tell MSan that memory initialized by zlib is valid. 79251607Sdim __msan_unpoison(UncompressedBuffer->getBufferStart(), UncompressedSize); 80251607Sdim } 81251607Sdim return Res; 82251607Sdim} 83251607Sdim 84263508Sdimuint32_t zlib::crc32(StringRef Buffer) { 85263508Sdim return ::crc32(0, (const Bytef *)Buffer.data(), Buffer.size()); 86263508Sdim} 87263508Sdim 88251607Sdim#else 89251607Sdimbool zlib::isAvailable() { return false; } 90251607Sdimzlib::Status zlib::compress(StringRef InputBuffer, 91251607Sdim OwningPtr<MemoryBuffer> &CompressedBuffer, 92251607Sdim CompressionLevel Level) { 93251607Sdim return zlib::StatusUnsupported; 94251607Sdim} 95251607Sdimzlib::Status zlib::uncompress(StringRef InputBuffer, 96251607Sdim OwningPtr<MemoryBuffer> &UncompressedBuffer, 97251607Sdim size_t UncompressedSize) { 98251607Sdim return zlib::StatusUnsupported; 99251607Sdim} 100263508Sdimuint32_t zlib::crc32(StringRef Buffer) { 101263508Sdim llvm_unreachable("zlib::crc32 is unavailable"); 102263508Sdim} 103251607Sdim#endif 104251607Sdim 105