2015-04-14 00:31:28 +00:00

83 lines
2.6 KiB
C++

//===- lib/ReaderWriter/ELF/ELFReader.h -----------------------------------===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLD_READER_WRITER_ELF_READER_H
#define LLD_READER_WRITER_ELF_READER_H
#include "DynamicFile.h"
#include "ELFFile.h"
#include "lld/Core/File.h"
#include "lld/Core/Reader.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Object/ELF.h"
namespace lld {
namespace elf {
template <typename ELFT, typename ContextT, template <typename> class FileT>
class ELFReader : public Reader {
public:
typedef llvm::object::Elf_Ehdr_Impl<ELFT> Elf_Ehdr;
ELFReader(ContextT &ctx) : _ctx(ctx) {}
bool canParse(file_magic magic, const MemoryBuffer &mb) const override {
return (FileT<ELFT>::canParse(magic) &&
elfHeader(mb)->e_machine == ContextT::machine);
}
std::error_code
loadFile(std::unique_ptr<MemoryBuffer> mb, const class Registry &,
std::vector<std::unique_ptr<File>> &result) const override {
const Elf_Ehdr *hdr = elfHeader(*mb);
if (auto ec = _ctx.mergeHeaderFlags(hdr->getFileClass(), hdr->e_flags))
return ec;
result.push_back(createELF(std::move(mb)));
return std::error_code();
}
private:
/// Create an object depending on the runtime attributes and alignment
/// of an ELF file.
std::unique_ptr<File> createELF(std::unique_ptr<MemoryBuffer> mb) const {
using namespace llvm::ELF;
using namespace llvm::support;
if (uintptr_t(mb->getBufferStart()) & 1)
llvm_unreachable("Invalid alignment for ELF file!");
unsigned char size;
unsigned char endian;
std::tie(size, endian) = llvm::object::getElfArchType(mb->getBuffer());
File *file = nullptr;
if (size == ELFCLASS32 && endian == ELFDATA2LSB) {
file = new FileT<ELF32LE>(std::move(mb), _ctx);
} else if (size == ELFCLASS32 && endian == ELFDATA2MSB) {
file = new FileT<ELF32BE>(std::move(mb), _ctx);
} else if (size == ELFCLASS64 && endian == ELFDATA2LSB) {
file = new FileT<ELF64LE>(std::move(mb), _ctx);
} else if (size == ELFCLASS64 && endian == ELFDATA2MSB) {
file = new FileT<ELF64BE>(std::move(mb), _ctx);
}
if (!file)
llvm_unreachable("Invalid ELF type!");
return std::unique_ptr<File>(file);
}
static const Elf_Ehdr *elfHeader(const MemoryBuffer &buf) {
return reinterpret_cast<const Elf_Ehdr *>(buf.getBuffer().data());
}
ContextT &_ctx;
};
} // namespace elf
} // namespace lld
#endif // LLD_READER_WRITER_ELF_READER_H