1 //===- ObjectFile.cpp - File format independent object file ---------------===// 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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file defines a file format independent ObjectFile class. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/Object/ObjectFile.h" 14 #include "llvm/ADT/StringRef.h" 15 #include "llvm/BinaryFormat/Magic.h" 16 #include "llvm/Object/Binary.h" 17 #include "llvm/Object/COFF.h" 18 #include "llvm/Object/Error.h" 19 #include "llvm/Object/MachO.h" 20 #include "llvm/Object/Wasm.h" 21 #include "llvm/Support/Error.h" 22 #include "llvm/Support/ErrorHandling.h" 23 #include "llvm/Support/ErrorOr.h" 24 #include "llvm/Support/FileSystem.h" 25 #include "llvm/Support/MemoryBuffer.h" 26 #include "llvm/Support/raw_ostream.h" 27 #include <algorithm> 28 #include <cstdint> 29 #include <memory> 30 #include <system_error> 31 32 using namespace llvm; 33 using namespace object; 34 35 raw_ostream &object::operator<<(raw_ostream &OS, const SectionedAddress &Addr) { 36 OS << "SectionedAddress{" << format_hex(Addr.Address, 10); 37 if (Addr.SectionIndex != SectionedAddress::UndefSection) 38 OS << ", " << Addr.SectionIndex; 39 return OS << "}"; 40 } 41 42 void ObjectFile::anchor() {} 43 44 ObjectFile::ObjectFile(unsigned int Type, MemoryBufferRef Source) 45 : SymbolicFile(Type, Source) {} 46 47 bool SectionRef::containsSymbol(SymbolRef S) const { 48 Expected<section_iterator> SymSec = S.getSection(); 49 if (!SymSec) { 50 // TODO: Actually report errors helpfully. 51 consumeError(SymSec.takeError()); 52 return false; 53 } 54 return *this == **SymSec; 55 } 56 57 uint64_t ObjectFile::getSymbolValue(DataRefImpl Ref) const { 58 uint32_t Flags = getSymbolFlags(Ref); 59 if (Flags & SymbolRef::SF_Undefined) 60 return 0; 61 if (Flags & SymbolRef::SF_Common) 62 return getCommonSymbolSize(Ref); 63 return getSymbolValueImpl(Ref); 64 } 65 66 Error ObjectFile::printSymbolName(raw_ostream &OS, DataRefImpl Symb) const { 67 Expected<StringRef> Name = getSymbolName(Symb); 68 if (!Name) 69 return Name.takeError(); 70 OS << *Name; 71 return Error::success(); 72 } 73 74 uint32_t ObjectFile::getSymbolAlignment(DataRefImpl DRI) const { return 0; } 75 76 bool ObjectFile::isSectionBitcode(DataRefImpl Sec) const { 77 Expected<StringRef> NameOrErr = getSectionName(Sec); 78 if (NameOrErr) 79 return *NameOrErr == ".llvmbc"; 80 consumeError(NameOrErr.takeError()); 81 return false; 82 } 83 84 bool ObjectFile::isSectionStripped(DataRefImpl Sec) const { return false; } 85 86 bool ObjectFile::isBerkeleyText(DataRefImpl Sec) const { 87 return isSectionText(Sec); 88 } 89 90 bool ObjectFile::isBerkeleyData(DataRefImpl Sec) const { 91 return isSectionData(Sec); 92 } 93 94 Expected<section_iterator> 95 ObjectFile::getRelocatedSection(DataRefImpl Sec) const { 96 return section_iterator(SectionRef(Sec, this)); 97 } 98 99 Triple ObjectFile::makeTriple() const { 100 Triple TheTriple; 101 auto Arch = getArch(); 102 TheTriple.setArch(Triple::ArchType(Arch)); 103 104 // For ARM targets, try to use the build attributes to build determine 105 // the build target. Target features are also added, but later during 106 // disassembly. 107 if (Arch == Triple::arm || Arch == Triple::armeb) 108 setARMSubArch(TheTriple); 109 110 // TheTriple defaults to ELF, and COFF doesn't have an environment: 111 // the best we can do here is indicate that it is mach-o. 112 if (isMachO()) 113 TheTriple.setObjectFormat(Triple::MachO); 114 115 if (isCOFF()) { 116 const auto COFFObj = cast<COFFObjectFile>(this); 117 if (COFFObj->getArch() == Triple::thumb) 118 TheTriple.setTriple("thumbv7-windows"); 119 } 120 121 return TheTriple; 122 } 123 124 Expected<std::unique_ptr<ObjectFile>> 125 ObjectFile::createObjectFile(MemoryBufferRef Object, file_magic Type) { 126 StringRef Data = Object.getBuffer(); 127 if (Type == file_magic::unknown) 128 Type = identify_magic(Data); 129 130 switch (Type) { 131 case file_magic::unknown: 132 case file_magic::bitcode: 133 case file_magic::coff_cl_gl_object: 134 case file_magic::archive: 135 case file_magic::macho_universal_binary: 136 case file_magic::windows_resource: 137 case file_magic::pdb: 138 case file_magic::minidump: 139 return errorCodeToError(object_error::invalid_file_type); 140 case file_magic::tapi_file: 141 return errorCodeToError(object_error::invalid_file_type); 142 case file_magic::elf: 143 case file_magic::elf_relocatable: 144 case file_magic::elf_executable: 145 case file_magic::elf_shared_object: 146 case file_magic::elf_core: 147 return createELFObjectFile(Object); 148 case file_magic::macho_object: 149 case file_magic::macho_executable: 150 case file_magic::macho_fixed_virtual_memory_shared_lib: 151 case file_magic::macho_core: 152 case file_magic::macho_preload_executable: 153 case file_magic::macho_dynamically_linked_shared_lib: 154 case file_magic::macho_dynamic_linker: 155 case file_magic::macho_bundle: 156 case file_magic::macho_dynamically_linked_shared_lib_stub: 157 case file_magic::macho_dsym_companion: 158 case file_magic::macho_kext_bundle: 159 return createMachOObjectFile(Object); 160 case file_magic::coff_object: 161 case file_magic::coff_import_library: 162 case file_magic::pecoff_executable: 163 return createCOFFObjectFile(Object); 164 case file_magic::xcoff_object_32: 165 return createXCOFFObjectFile(Object, Binary::ID_XCOFF32); 166 case file_magic::xcoff_object_64: 167 return createXCOFFObjectFile(Object, Binary::ID_XCOFF64); 168 case file_magic::wasm_object: 169 return createWasmObjectFile(Object); 170 } 171 llvm_unreachable("Unexpected Object File Type"); 172 } 173 174 Expected<OwningBinary<ObjectFile>> 175 ObjectFile::createObjectFile(StringRef ObjectPath) { 176 ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr = 177 MemoryBuffer::getFile(ObjectPath); 178 if (std::error_code EC = FileOrErr.getError()) 179 return errorCodeToError(EC); 180 std::unique_ptr<MemoryBuffer> Buffer = std::move(FileOrErr.get()); 181 182 Expected<std::unique_ptr<ObjectFile>> ObjOrErr = 183 createObjectFile(Buffer->getMemBufferRef()); 184 if (Error Err = ObjOrErr.takeError()) 185 return std::move(Err); 186 std::unique_ptr<ObjectFile> Obj = std::move(ObjOrErr.get()); 187 188 return OwningBinary<ObjectFile>(std::move(Obj), std::move(Buffer)); 189 } 190