--- /dev/null
+//===-- Decompressor.h ------------------------------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===/
+
+#ifndef LLVM_OBJECT_DECOMPRESSOR_H
+#define LLVM_OBJECT_DECOMPRESSOR_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/Object/ObjectFile.h"
+
+namespace llvm {
+namespace object {
+
+/// @brief Decompressor helps to handle decompression of compressed sections.
+class Decompressor {
+public:
+ /// @brief Create decompressor object.
+ /// @param Name Section name.
+ /// @param Data Section content.
+ /// @param IsLE Flag determines if Data is in little endian form.
+ /// @param Name Flag determines if object is 64 bit.
+ static Expected<Decompressor> create(StringRef Name, StringRef Data,
+ bool IsLE, bool Is64Bit);
+
+ /// @brief Resize the buffer and uncompress section data into it.
+ /// @param Out Destination buffer.
+ Error decompress(SmallString<32> &Out);
+
+ /// @brief Uncompress section data to raw buffer provided.
+ /// @param Buffer Destination buffer.
+ Error decompress(MutableArrayRef<char> Buffer);
+
+ /// @brief Return memory buffer size required for decompression.
+ uint64_t getDecompressedSize() { return DecompressedSize; }
+
+ /// @brief Return true if section is compressed, including gnu-styled case.
+ static bool isCompressed(const object::SectionRef &Section);
+
+ /// @brief Return true if section is a ELF compressed one.
+ static bool isCompressedELFSection(uint64_t Flags, StringRef Name);
+
+ /// @brief Return true if section name matches gnu style compressed one.
+ static bool isGnuStyle(StringRef Name);
+
+private:
+ Decompressor(StringRef Data);
+
+ Error consumeCompressedGnuHeader();
+ Error consumeCompressedZLibHeader(bool Is64Bit, bool IsLittleEndian);
+
+ StringRef SectionData;
+ uint64_t DecompressedSize;
+};
+
+} // end namespace object
+} // end namespace llvm
+
+#endif // LLVM_OBJECT_DECOMPRESSOR_H
#include "llvm/DebugInfo/DWARF/DWARFDebugArangeSet.h"
#include "llvm/DebugInfo/DWARF/DWARFDebugPubTable.h"
#include "llvm/DebugInfo/DWARF/DWARFUnitIndex.h"
+#include "llvm/Object/Decompressor.h"
#include "llvm/Object/MachO.h"
#include "llvm/Object/RelocVisitor.h"
#include "llvm/Support/Compression.h"
return InliningInfo;
}
-static bool consumeCompressedGnuHeader(StringRef &data,
- uint64_t &OriginalSize) {
- // Consume "ZLIB" prefix.
- if (!data.startswith("ZLIB"))
- return false;
- data = data.substr(4);
- // Consume uncompressed section size (big-endian 8 bytes).
- DataExtractor extractor(data, false, 8);
- uint32_t Offset = 0;
- OriginalSize = extractor.getU64(&Offset);
- if (Offset == 0)
- return false;
- data = data.substr(Offset);
- return true;
-}
-
-static bool consumeCompressedZLibHeader(StringRef &Data, uint64_t &OriginalSize,
- bool IsLE, bool Is64Bit) {
- using namespace ELF;
- uint64_t HdrSize = Is64Bit ? sizeof(Elf64_Chdr) : sizeof(Elf32_Chdr);
- if (Data.size() < HdrSize)
- return false;
-
- DataExtractor Extractor(Data, IsLE, 0);
- uint32_t Offset = 0;
- if (Extractor.getUnsigned(&Offset, Is64Bit ? sizeof(Elf64_Word)
- : sizeof(Elf32_Word)) !=
- ELFCOMPRESS_ZLIB)
- return false;
-
- // Skip Elf64_Chdr::ch_reserved field.
- if (Is64Bit)
- Offset += sizeof(Elf64_Word);
-
- OriginalSize = Extractor.getUnsigned(&Offset, Is64Bit ? sizeof(Elf64_Xword)
- : sizeof(Elf32_Word));
- Data = Data.substr(HdrSize);
- return true;
-}
-
-static bool tryDecompress(StringRef &Name, StringRef &Data,
- SmallString<32> &Out, bool ZLibStyle, bool IsLE,
- bool Is64Bit) {
- if (!zlib::isAvailable())
- return false;
-
- uint64_t OriginalSize;
- bool Result =
- ZLibStyle ? consumeCompressedZLibHeader(Data, OriginalSize, IsLE, Is64Bit)
- : consumeCompressedGnuHeader(Data, OriginalSize);
-
- if (!Result || zlib::uncompress(Data, Out, OriginalSize) != zlib::StatusOK)
- return false;
-
- // gnu-style names are started from "z", consume that.
- if (!ZLibStyle)
- Name = Name.substr(1);
- return true;
-}
-
DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
const LoadedObjectInfo *L)
: IsLittleEndian(Obj.isLittleEndian()),
if (!L || !L->getLoadedSectionContents(*RelocatedSection,data))
Section.getContents(data);
- name = name.substr(name.find_first_not_of("._")); // Skip . and _ prefixes.
-
- bool ZLibStyleCompressed = Section.isCompressed();
- if (ZLibStyleCompressed || name.startswith("zdebug_")) {
+ if (Decompressor::isCompressed(Section)) {
+ Expected<Decompressor> Decompressor =
+ Decompressor::create(name, data, IsLittleEndian, AddressSize == 8);
+ if (!Decompressor)
+ continue;
SmallString<32> Out;
- if (!tryDecompress(name, data, Out, ZLibStyleCompressed, IsLittleEndian,
- AddressSize == 8))
+ if (auto Err = Decompressor->decompress(Out))
continue;
UncompressedSections.emplace_back(std::move(Out));
data = UncompressedSections.back();
}
+ // Compressed sections names in GNU style starts from ".z",
+ // at this point section is decompressed and we drop compression prefix.
+ name = name.substr(
+ name.find_first_not_of("._z")); // Skip ".", "z" and "_" prefixes.
+
StringRef *SectionData =
StringSwitch<StringRef *>(name)
.Case("debug_info", &InfoSection.Data)
ArchiveWriter.cpp
Binary.cpp
COFFObjectFile.cpp
+ Decompressor.cpp
ELF.cpp
ELFObjectFile.cpp
Error.cpp
--- /dev/null
+//===-- Decompressor.cpp --------------------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Object/Decompressor.h"
+#include "llvm/Object/ELFObjectFile.h"
+#include "llvm/Support/Compression.h"
+#include "llvm/Support/DataExtractor.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/ELF.h"
+
+using namespace llvm;
+using namespace llvm::support::endian;
+using namespace object;
+
+Expected<Decompressor> Decompressor::create(StringRef Name, StringRef Data,
+ bool IsLE, bool Is64Bit) {
+ if (!zlib::isAvailable())
+ return createError("zlib is not available");
+
+ Decompressor D(Data);
+ Error Err = isGnuStyle(Name) ? D.consumeCompressedGnuHeader()
+ : D.consumeCompressedZLibHeader(Is64Bit, IsLE);
+ if (Err)
+ return std::move(Err);
+ return D;
+}
+
+Decompressor::Decompressor(StringRef Data)
+ : SectionData(Data), DecompressedSize(0) {}
+
+Error Decompressor::consumeCompressedGnuHeader() {
+ if (!SectionData.startswith("ZLIB"))
+ return createError("corrupted compressed section header");
+
+ SectionData = SectionData.substr(4);
+
+ // Consume uncompressed section size (big-endian 8 bytes).
+ if (SectionData.size() < 8)
+ return createError("corrupted uncompressed section size");
+ DecompressedSize = read64be(SectionData.data());
+ SectionData = SectionData.substr(8);
+
+ return Error::success();
+}
+
+Error Decompressor::consumeCompressedZLibHeader(bool Is64Bit,
+ bool IsLittleEndian) {
+ using namespace ELF;
+ uint64_t HdrSize = Is64Bit ? sizeof(Elf64_Chdr) : sizeof(Elf32_Chdr);
+ if (SectionData.size() < HdrSize)
+ return createError("corrupted compressed section header");
+
+ DataExtractor Extractor(SectionData, IsLittleEndian, 0);
+ uint32_t Offset = 0;
+ if (Extractor.getUnsigned(&Offset, Is64Bit ? sizeof(Elf64_Word)
+ : sizeof(Elf32_Word)) !=
+ ELFCOMPRESS_ZLIB)
+ return createError("unsupported compression type");
+
+ // Skip Elf64_Chdr::ch_reserved field.
+ if (Is64Bit)
+ Offset += sizeof(Elf64_Word);
+
+ DecompressedSize = Extractor.getUnsigned(
+ &Offset, Is64Bit ? sizeof(Elf64_Xword) : sizeof(Elf32_Word));
+ SectionData = SectionData.substr(HdrSize);
+ return Error::success();
+}
+
+bool Decompressor::isGnuStyle(StringRef Name) {
+ return Name.startswith(".zdebug");
+}
+
+bool Decompressor::isCompressed(const object::SectionRef &Section) {
+ StringRef Name;
+ if (std::error_code E = Section.getName(Name))
+ return false;
+ return Section.isCompressed() || isGnuStyle(Name);
+}
+
+bool Decompressor::isCompressedELFSection(uint64_t Flags, StringRef Name) {
+ return (Flags & ELF::SHF_COMPRESSED) || isGnuStyle(Name);
+}
+
+Error Decompressor::decompress(SmallString<32> &Out) {
+ Out.resize(DecompressedSize);
+ return decompress({Out.data(), (size_t)DecompressedSize});
+}
+
+Error Decompressor::decompress(MutableArrayRef<char> Buffer) {
+ size_t Size = Buffer.size();
+ zlib::Status Status = zlib::uncompress(SectionData, Buffer.data(), Size);
+ if (Status != zlib::StatusOK)
+ return createError("decompression failed");
+ return Error::success();
+}
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