147 lines · cpp
1//===-- LZMA.cpp ----------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "lldb/Host/Config.h"10#include "llvm/ADT/StringRef.h"11#include "llvm/Support/Error.h"12 13#if LLDB_ENABLE_LZMA14#include <lzma.h>15#endif // LLDB_ENABLE_LZMA16 17namespace lldb_private {18 19namespace lzma {20 21#if !LLDB_ENABLE_LZMA22bool isAvailable() { return false; }23llvm::Expected<uint64_t>24getUncompressedSize(llvm::ArrayRef<uint8_t> InputBuffer) {25 llvm_unreachable("lzma::getUncompressedSize is unavailable");26}27 28llvm::Error uncompress(llvm::ArrayRef<uint8_t> InputBuffer,29 llvm::SmallVectorImpl<uint8_t> &Uncompressed) {30 llvm_unreachable("lzma::uncompress is unavailable");31}32 33#else // LLDB_ENABLE_LZMA34 35bool isAvailable() { return true; }36 37static const char *convertLZMACodeToString(lzma_ret Code) {38 switch (Code) {39 case LZMA_STREAM_END:40 return "lzma error: LZMA_STREAM_END";41 case LZMA_NO_CHECK:42 return "lzma error: LZMA_NO_CHECK";43 case LZMA_UNSUPPORTED_CHECK:44 return "lzma error: LZMA_UNSUPPORTED_CHECK";45 case LZMA_GET_CHECK:46 return "lzma error: LZMA_GET_CHECK";47 case LZMA_MEM_ERROR:48 return "lzma error: LZMA_MEM_ERROR";49 case LZMA_MEMLIMIT_ERROR:50 return "lzma error: LZMA_MEMLIMIT_ERROR";51 case LZMA_FORMAT_ERROR:52 return "lzma error: LZMA_FORMAT_ERROR";53 case LZMA_OPTIONS_ERROR:54 return "lzma error: LZMA_OPTIONS_ERROR";55 case LZMA_DATA_ERROR:56 return "lzma error: LZMA_DATA_ERROR";57 case LZMA_BUF_ERROR:58 return "lzma error: LZMA_BUF_ERROR";59 case LZMA_PROG_ERROR:60 return "lzma error: LZMA_PROG_ERROR";61 default:62 llvm_unreachable("unknown or unexpected lzma status code");63 }64}65 66llvm::Expected<uint64_t>67getUncompressedSize(llvm::ArrayRef<uint8_t> InputBuffer) {68 lzma_stream_flags opts{};69 if (InputBuffer.size() < LZMA_STREAM_HEADER_SIZE) {70 return llvm::createStringError(71 llvm::inconvertibleErrorCode(),72 "size of xz-compressed blob (%lu bytes) is smaller than the "73 "LZMA_STREAM_HEADER_SIZE (%lu bytes)",74 InputBuffer.size(), LZMA_STREAM_HEADER_SIZE);75 }76 77 // Decode xz footer.78 lzma_ret xzerr = lzma_stream_footer_decode(79 &opts, InputBuffer.take_back(LZMA_STREAM_HEADER_SIZE).data());80 if (xzerr != LZMA_OK) {81 return llvm::createStringError(llvm::inconvertibleErrorCode(),82 "lzma_stream_footer_decode()=%s",83 convertLZMACodeToString(xzerr));84 }85 if (InputBuffer.size() < (opts.backward_size + LZMA_STREAM_HEADER_SIZE)) {86 return llvm::createStringError(87 llvm::inconvertibleErrorCode(),88 "xz-compressed buffer size (%lu bytes) too small (required at "89 "least %lu bytes) ",90 InputBuffer.size(), (opts.backward_size + LZMA_STREAM_HEADER_SIZE));91 }92 93 // Decode xz index.94 lzma_index *xzindex;95 uint64_t memlimit(UINT64_MAX);96 size_t inpos = 0;97 xzerr = lzma_index_buffer_decode(98 &xzindex, &memlimit, nullptr,99 InputBuffer.take_back(LZMA_STREAM_HEADER_SIZE + opts.backward_size)100 .data(),101 &inpos, InputBuffer.size());102 if (xzerr != LZMA_OK) {103 return llvm::createStringError(llvm::inconvertibleErrorCode(),104 "lzma_index_buffer_decode()=%s",105 convertLZMACodeToString(xzerr));106 }107 108 // Get size of uncompressed file to construct an in-memory buffer of the109 // same size on the calling end (if needed).110 uint64_t uncompressedSize = lzma_index_uncompressed_size(xzindex);111 112 // Deallocate xz index as it is no longer needed.113 lzma_index_end(xzindex, nullptr);114 115 return uncompressedSize;116}117 118llvm::Error uncompress(llvm::ArrayRef<uint8_t> InputBuffer,119 llvm::SmallVectorImpl<uint8_t> &Uncompressed) {120 llvm::Expected<uint64_t> uncompressedSize = getUncompressedSize(InputBuffer);121 122 if (auto err = uncompressedSize.takeError())123 return err;124 125 Uncompressed.resize(*uncompressedSize);126 127 // Decompress xz buffer to buffer.128 uint64_t memlimit = UINT64_MAX;129 size_t inpos = 0;130 size_t outpos = 0;131 lzma_ret ret = lzma_stream_buffer_decode(132 &memlimit, 0, nullptr, InputBuffer.data(), &inpos, InputBuffer.size(),133 Uncompressed.data(), &outpos, Uncompressed.size());134 if (ret != LZMA_OK) {135 return llvm::createStringError(llvm::inconvertibleErrorCode(),136 "lzma_stream_buffer_decode()=%s",137 convertLZMACodeToString(ret));138 }139 140 return llvm::Error::success();141}142 143#endif // LLDB_ENABLE_LZMA144 145} // end of namespace lzma146} // namespace lldb_private147