| //===--- Compression.cpp - Compression implementation ---------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements compression functions. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Support/Compression.h" |
| #include "llvm/ADT/OwningPtr.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/Config/config.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/MemoryBuffer.h" |
| #if LLVM_ENABLE_ZLIB == 1 && HAVE_ZLIB_H |
| #include <zlib.h> |
| #endif |
| |
| using namespace llvm; |
| |
| #if LLVM_ENABLE_ZLIB == 1 && HAVE_LIBZ |
| static int encodeZlibCompressionLevel(zlib::CompressionLevel Level) { |
| switch (Level) { |
| case zlib::NoCompression: return 0; |
| case zlib::BestSpeedCompression: return 1; |
| case zlib::DefaultCompression: return Z_DEFAULT_COMPRESSION; |
| case zlib::BestSizeCompression: return 9; |
| } |
| llvm_unreachable("Invalid zlib::CompressionLevel!"); |
| } |
| |
| static zlib::Status encodeZlibReturnValue(int ReturnValue) { |
| switch (ReturnValue) { |
| case Z_OK: return zlib::StatusOK; |
| case Z_MEM_ERROR: return zlib::StatusOutOfMemory; |
| case Z_BUF_ERROR: return zlib::StatusBufferTooShort; |
| case Z_STREAM_ERROR: return zlib::StatusInvalidArg; |
| case Z_DATA_ERROR: return zlib::StatusInvalidData; |
| default: llvm_unreachable("unknown zlib return status!"); |
| } |
| } |
| |
| bool zlib::isAvailable() { return true; } |
| zlib::Status zlib::compress(StringRef InputBuffer, |
| OwningPtr<MemoryBuffer> &CompressedBuffer, |
| CompressionLevel Level) { |
| unsigned long CompressedSize = ::compressBound(InputBuffer.size()); |
| OwningArrayPtr<char> TmpBuffer(new char[CompressedSize]); |
| int CLevel = encodeZlibCompressionLevel(Level); |
| Status Res = encodeZlibReturnValue(::compress2( |
| (Bytef *)TmpBuffer.get(), &CompressedSize, |
| (const Bytef *)InputBuffer.data(), InputBuffer.size(), CLevel)); |
| if (Res == StatusOK) { |
| CompressedBuffer.reset(MemoryBuffer::getMemBufferCopy( |
| StringRef(TmpBuffer.get(), CompressedSize))); |
| // Tell MSan that memory initialized by zlib is valid. |
| __msan_unpoison(CompressedBuffer->getBufferStart(), CompressedSize); |
| } |
| return Res; |
| } |
| |
| zlib::Status zlib::uncompress(StringRef InputBuffer, |
| OwningPtr<MemoryBuffer> &UncompressedBuffer, |
| size_t UncompressedSize) { |
| OwningArrayPtr<char> TmpBuffer(new char[UncompressedSize]); |
| Status Res = encodeZlibReturnValue( |
| ::uncompress((Bytef *)TmpBuffer.get(), (uLongf *)&UncompressedSize, |
| (const Bytef *)InputBuffer.data(), InputBuffer.size())); |
| if (Res == StatusOK) { |
| UncompressedBuffer.reset(MemoryBuffer::getMemBufferCopy( |
| StringRef(TmpBuffer.get(), UncompressedSize))); |
| // Tell MSan that memory initialized by zlib is valid. |
| __msan_unpoison(UncompressedBuffer->getBufferStart(), UncompressedSize); |
| } |
| return Res; |
| } |
| |
| #else |
| bool zlib::isAvailable() { return false; } |
| zlib::Status zlib::compress(StringRef InputBuffer, |
| OwningPtr<MemoryBuffer> &CompressedBuffer, |
| CompressionLevel Level) { |
| return zlib::StatusUnsupported; |
| } |
| zlib::Status zlib::uncompress(StringRef InputBuffer, |
| OwningPtr<MemoryBuffer> &UncompressedBuffer, |
| size_t UncompressedSize) { |
| return zlib::StatusUnsupported; |
| } |
| #endif |
| |