llvm-6502/lib/Object/ObjectFile.cpp
Rafael Espindola 548f2b6e8f Don't own the buffer in object::Binary.
Owning the buffer is somewhat inflexible. Some Binaries have sub Binaries
(like Archive) and we had to create dummy buffers just to handle that. It is
also a bad fit for IRObjectFile where the Module wants to own the buffer too.

Keeping this ownership would make supporting IR inside native objects
particularly painful.

This patch focuses in lib/Object. If something elsewhere used to own an Binary,
now it also owns a MemoryBuffer.

This patch introduces a few new types.

* MemoryBufferRef. This is just a pair of StringRefs for the data and name.
  This is to MemoryBuffer as StringRef is to std::string.
* OwningBinary. A combination of Binary and a MemoryBuffer. This is needed
  for convenience functions that take a filename and return both the
  buffer and the Binary using that buffer.

The C api now uses OwningBinary to avoid any change in semantics. I will start
a new thread to see if we want to change it and how.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216002 91177308-0d34-0410-b5e6-96231b3b80d8
2014-08-19 18:44:46 +00:00

103 lines
3.6 KiB
C++

//===- ObjectFile.cpp - File format independent object file -----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a file format independent ObjectFile class.
//
//===----------------------------------------------------------------------===//
#include "llvm/Object/COFF.h"
#include "llvm/Object/MachO.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MemoryBuffer.h"
#include "llvm/Support/raw_ostream.h"
#include <system_error>
using namespace llvm;
using namespace object;
void ObjectFile::anchor() { }
ObjectFile::ObjectFile(unsigned int Type, MemoryBufferRef Source)
: SymbolicFile(Type, Source) {}
std::error_code ObjectFile::printSymbolName(raw_ostream &OS,
DataRefImpl Symb) const {
StringRef Name;
if (std::error_code EC = getSymbolName(Symb, Name))
return EC;
OS << Name;
return object_error::success;
}
std::error_code ObjectFile::getSymbolAlignment(DataRefImpl DRI,
uint32_t &Result) const {
Result = 0;
return object_error::success;
}
section_iterator ObjectFile::getRelocatedSection(DataRefImpl Sec) const {
return section_iterator(SectionRef(Sec, this));
}
ErrorOr<std::unique_ptr<ObjectFile>>
ObjectFile::createObjectFile(MemoryBufferRef Object, sys::fs::file_magic Type) {
StringRef Data = Object.getBuffer();
if (Type == sys::fs::file_magic::unknown)
Type = sys::fs::identify_magic(Data);
switch (Type) {
case sys::fs::file_magic::unknown:
case sys::fs::file_magic::bitcode:
case sys::fs::file_magic::archive:
case sys::fs::file_magic::macho_universal_binary:
case sys::fs::file_magic::windows_resource:
return object_error::invalid_file_type;
case sys::fs::file_magic::elf_relocatable:
case sys::fs::file_magic::elf_executable:
case sys::fs::file_magic::elf_shared_object:
case sys::fs::file_magic::elf_core:
return createELFObjectFile(Object);
case sys::fs::file_magic::macho_object:
case sys::fs::file_magic::macho_executable:
case sys::fs::file_magic::macho_fixed_virtual_memory_shared_lib:
case sys::fs::file_magic::macho_core:
case sys::fs::file_magic::macho_preload_executable:
case sys::fs::file_magic::macho_dynamically_linked_shared_lib:
case sys::fs::file_magic::macho_dynamic_linker:
case sys::fs::file_magic::macho_bundle:
case sys::fs::file_magic::macho_dynamically_linked_shared_lib_stub:
case sys::fs::file_magic::macho_dsym_companion:
return createMachOObjectFile(Object);
case sys::fs::file_magic::coff_object:
case sys::fs::file_magic::coff_import_library:
case sys::fs::file_magic::pecoff_executable:
return createCOFFObjectFile(Object);
}
llvm_unreachable("Unexpected Object File Type");
}
ErrorOr<OwningBinary<ObjectFile>>
ObjectFile::createObjectFile(StringRef ObjectPath) {
ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
MemoryBuffer::getFile(ObjectPath);
if (std::error_code EC = FileOrErr.getError())
return EC;
std::unique_ptr<MemoryBuffer> Buffer = std::move(FileOrErr.get());
ErrorOr<std::unique_ptr<ObjectFile>> ObjOrErr =
createObjectFile(Buffer->getMemBufferRef());
if (std::error_code EC = ObjOrErr.getError())
return EC;
std::unique_ptr<ObjectFile> Obj = std::move(ObjOrErr.get());
return OwningBinary<ObjectFile>(std::move(Obj), std::move(Buffer));
}