ObjectFile.cpp revision 309124 
1//===- ObjectFile.cpp - File format independent object file -----*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines a file format independent ObjectFile class.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/Object/COFF.h"
15#include "llvm/Object/MachO.h"
16#include "llvm/Object/ObjectFile.h"
17#include "llvm/Support/ErrorHandling.h"
18#include "llvm/Support/FileSystem.h"
19#include "llvm/Support/MemoryBuffer.h"
20#include "llvm/Support/raw_ostream.h"
21#include <system_error>
22
23using namespace llvm;
24using namespace object;
25
26void ObjectFile::anchor() { }
27
28ObjectFile::ObjectFile(unsigned int Type, MemoryBufferRef Source)
29    : SymbolicFile(Type, Source) {}
30
31bool SectionRef::containsSymbol(SymbolRef S) const {
32  Expected<section_iterator> SymSec = S.getSection();
33  if (!SymSec) {
34    // TODO: Actually report errors helpfully.
35    consumeError(SymSec.takeError());
36    return false;
37  }
38  return *this == **SymSec;
39}
40
41uint64_t ObjectFile::getSymbolValue(DataRefImpl Ref) const {
42  uint32_t Flags = getSymbolFlags(Ref);
43  if (Flags & SymbolRef::SF_Undefined)
44    return 0;
45  if (Flags & SymbolRef::SF_Common)
46    return getCommonSymbolSize(Ref);
47  return getSymbolValueImpl(Ref);
48}
49
50std::error_code ObjectFile::printSymbolName(raw_ostream &OS,
51                                            DataRefImpl Symb) const {
52  Expected<StringRef> Name = getSymbolName(Symb);
53  if (!Name)
54    return errorToErrorCode(Name.takeError());
55  OS << *Name;
56  return std::error_code();
57}
58
59uint32_t ObjectFile::getSymbolAlignment(DataRefImpl DRI) const { return 0; }
60
61bool ObjectFile::isSectionBitcode(DataRefImpl Sec) const {
62  StringRef SectName;
63  if (!getSectionName(Sec, SectName))
64    return SectName == ".llvmbc";
65  return false;
66}
67
68section_iterator ObjectFile::getRelocatedSection(DataRefImpl Sec) const {
69  return section_iterator(SectionRef(Sec, this));
70}
71
72Expected<std::unique_ptr<ObjectFile>>
73ObjectFile::createObjectFile(MemoryBufferRef Object, sys::fs::file_magic Type) {
74  StringRef Data = Object.getBuffer();
75  if (Type == sys::fs::file_magic::unknown)
76    Type = sys::fs::identify_magic(Data);
77
78  switch (Type) {
79  case sys::fs::file_magic::unknown:
80  case sys::fs::file_magic::bitcode:
81  case sys::fs::file_magic::archive:
82  case sys::fs::file_magic::macho_universal_binary:
83  case sys::fs::file_magic::windows_resource:
84    return errorCodeToError(object_error::invalid_file_type);
85  case sys::fs::file_magic::elf:
86  case sys::fs::file_magic::elf_relocatable:
87  case sys::fs::file_magic::elf_executable:
88  case sys::fs::file_magic::elf_shared_object:
89  case sys::fs::file_magic::elf_core:
90    return errorOrToExpected(createELFObjectFile(Object));
91  case sys::fs::file_magic::macho_object:
92  case sys::fs::file_magic::macho_executable:
93  case sys::fs::file_magic::macho_fixed_virtual_memory_shared_lib:
94  case sys::fs::file_magic::macho_core:
95  case sys::fs::file_magic::macho_preload_executable:
96  case sys::fs::file_magic::macho_dynamically_linked_shared_lib:
97  case sys::fs::file_magic::macho_dynamic_linker:
98  case sys::fs::file_magic::macho_bundle:
99  case sys::fs::file_magic::macho_dynamically_linked_shared_lib_stub:
100  case sys::fs::file_magic::macho_dsym_companion:
101  case sys::fs::file_magic::macho_kext_bundle:
102    return createMachOObjectFile(Object);
103  case sys::fs::file_magic::coff_object:
104  case sys::fs::file_magic::coff_import_library:
105  case sys::fs::file_magic::pecoff_executable:
106    return errorOrToExpected(createCOFFObjectFile(Object));
107  }
108  llvm_unreachable("Unexpected Object File Type");
109}
110
111Expected<OwningBinary<ObjectFile>>
112ObjectFile::createObjectFile(StringRef ObjectPath) {
113  ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
114      MemoryBuffer::getFile(ObjectPath);
115  if (std::error_code EC = FileOrErr.getError())
116    return errorCodeToError(EC);
117  std::unique_ptr<MemoryBuffer> Buffer = std::move(FileOrErr.get());
118
119  Expected<std::unique_ptr<ObjectFile>> ObjOrErr =
120      createObjectFile(Buffer->getMemBufferRef());
121  if (!ObjOrErr)
122    ObjOrErr.takeError();
123  std::unique_ptr<ObjectFile> Obj = std::move(ObjOrErr.get());
124
125  return OwningBinary<ObjectFile>(std::move(Obj), std::move(Buffer));
126}
127