diff options
Diffstat (limited to 'llvm/tools/llvm-objcopy')
-rw-r--r-- | llvm/tools/llvm-objcopy/Object.cpp | 602 | ||||
-rw-r--r-- | llvm/tools/llvm-objcopy/Object.h | 325 | ||||
-rw-r--r-- | llvm/tools/llvm-objcopy/llvm-objcopy.cpp | 134 | ||||
-rw-r--r-- | llvm/tools/llvm-objcopy/llvm-objcopy.h | 3 |
4 files changed, 627 insertions, 437 deletions
diff --git a/llvm/tools/llvm-objcopy/Object.cpp b/llvm/tools/llvm-objcopy/Object.cpp index 944075d6197..c7b4c1f3dd3 100644 --- a/llvm/tools/llvm-objcopy/Object.cpp +++ b/llvm/tools/llvm-objcopy/Object.cpp @@ -30,61 +30,73 @@ using namespace llvm; using namespace object; using namespace ELF; -template <class ELFT> void Segment::writeHeader(FileOutputBuffer &Out) const { +template <class ELFT> void ELFWriter<ELFT>::writePhdr(const Segment &Seg) { using Elf_Ehdr = typename ELFT::Ehdr; using Elf_Phdr = typename ELFT::Phdr; - uint8_t *Buf = Out.getBufferStart(); - Buf += sizeof(Elf_Ehdr) + Index * sizeof(Elf_Phdr); + uint8_t *Buf = BufPtr->getBufferStart(); + Buf += sizeof(Elf_Ehdr) + Seg.Index * sizeof(Elf_Phdr); Elf_Phdr &Phdr = *reinterpret_cast<Elf_Phdr *>(Buf); - Phdr.p_type = Type; - Phdr.p_flags = Flags; - Phdr.p_offset = Offset; - Phdr.p_vaddr = VAddr; - Phdr.p_paddr = PAddr; - Phdr.p_filesz = FileSize; - Phdr.p_memsz = MemSize; - Phdr.p_align = Align; -} - -void Segment::writeSegment(FileOutputBuffer &Out) const { - uint8_t *Buf = Out.getBufferStart() + Offset; - // We want to maintain segments' interstitial data and contents exactly. - // This lets us just copy segments directly. - std::copy(std::begin(Contents), std::end(Contents), Buf); + Phdr.p_type = Seg.Type; + Phdr.p_flags = Seg.Flags; + Phdr.p_offset = Seg.Offset; + Phdr.p_vaddr = Seg.VAddr; + Phdr.p_paddr = Seg.PAddr; + Phdr.p_filesz = Seg.FileSize; + Phdr.p_memsz = Seg.MemSize; + Phdr.p_align = Seg.Align; } void SectionBase::removeSectionReferences(const SectionBase *Sec) {} void SectionBase::initialize(SectionTableRef SecTable) {} void SectionBase::finalize() {} -template <class ELFT> -void SectionBase::writeHeader(FileOutputBuffer &Out) const { - uint8_t *Buf = Out.getBufferStart(); - Buf += HeaderOffset; +template <class ELFT> void ELFWriter<ELFT>::writeShdr(const SectionBase &Sec) { + uint8_t *Buf = BufPtr->getBufferStart(); + Buf += Sec.HeaderOffset; typename ELFT::Shdr &Shdr = *reinterpret_cast<typename ELFT::Shdr *>(Buf); - Shdr.sh_name = NameIndex; - Shdr.sh_type = Type; - Shdr.sh_flags = Flags; - Shdr.sh_addr = Addr; - Shdr.sh_offset = Offset; - Shdr.sh_size = Size; - Shdr.sh_link = Link; - Shdr.sh_info = Info; - Shdr.sh_addralign = Align; - Shdr.sh_entsize = EntrySize; -} - -void Section::writeSection(FileOutputBuffer &Out) const { - if (Type == SHT_NOBITS) + Shdr.sh_name = Sec.NameIndex; + Shdr.sh_type = Sec.Type; + Shdr.sh_flags = Sec.Flags; + Shdr.sh_addr = Sec.Addr; + Shdr.sh_offset = Sec.Offset; + Shdr.sh_size = Sec.Size; + Shdr.sh_link = Sec.Link; + Shdr.sh_info = Sec.Info; + Shdr.sh_addralign = Sec.Align; + Shdr.sh_entsize = Sec.EntrySize; +} + +SectionVisitor::~SectionVisitor() {} + +void BinarySectionWriter::visit(const SymbolTableSection &Sec) { + error("Cannot write symbol table '" + Sec.Name + "' out to binary"); +} + +void BinarySectionWriter::visit(const RelocationSection &Sec) { + error("Cannot write relocation section '" + Sec.Name + "' out to binary"); +} + +void BinarySectionWriter::visit(const GnuDebugLinkSection &Sec) { + error("Cannot write '.gnu_debuglink' out to binary"); +} + +void SectionWriter::visit(const Section &Sec) { + if (Sec.Type == SHT_NOBITS) return; - uint8_t *Buf = Out.getBufferStart() + Offset; - std::copy(std::begin(Contents), std::end(Contents), Buf); + uint8_t *Buf = Out.getBufferStart() + Sec.Offset; + std::copy(std::begin(Sec.Contents), std::end(Sec.Contents), Buf); } -void OwnedDataSection::writeSection(FileOutputBuffer &Out) const { - uint8_t *Buf = Out.getBufferStart() + Offset; - std::copy(std::begin(Data), std::end(Data), Buf); +void Section::accept(SectionVisitor &Visitor) const { Visitor.visit(*this); } + +void SectionWriter::visit(const OwnedDataSection &Sec) { + uint8_t *Buf = Out.getBufferStart() + Sec.Offset; + std::copy(std::begin(Sec.Data), std::end(Sec.Data), Buf); +} + +void OwnedDataSection::accept(SectionVisitor &Visitor) const { + Visitor.visit(*this); } void StringTableSection::addString(StringRef Name) { @@ -98,8 +110,12 @@ uint32_t StringTableSection::findIndex(StringRef Name) const { void StringTableSection::finalize() { StrTabBuilder.finalize(); } -void StringTableSection::writeSection(FileOutputBuffer &Out) const { - StrTabBuilder.write(Out.getBufferStart() + Offset); +void SectionWriter::visit(const StringTableSection &Sec) { + Sec.StrTabBuilder.write(Out.getBufferStart() + Sec.Offset); +} + +void StringTableSection::accept(SectionVisitor &Visitor) const { + Visitor.visit(*this); } static bool isValidReservedSectionIndex(uint16_t Index, uint16_t Machine) { @@ -234,12 +250,12 @@ const Symbol *SymbolTableSection::getSymbolByIndex(uint32_t Index) const { } template <class ELFT> -void SymbolTableSectionImpl<ELFT>::writeSection(FileOutputBuffer &Out) const { +void ELFSectionWriter<ELFT>::visit(const SymbolTableSection &Sec) { uint8_t *Buf = Out.getBufferStart(); - Buf += Offset; + Buf += Sec.Offset; typename ELFT::Sym *Sym = reinterpret_cast<typename ELFT::Sym *>(Buf); // Loop though symbols setting each entry of the symbol table. - for (auto &Symbol : Symbols) { + for (auto &Symbol : Sec.Symbols) { Sym->st_name = Symbol->NameIndex; Sym->st_value = Symbol->Value; Sym->st_size = Symbol->Size; @@ -251,6 +267,10 @@ void SymbolTableSectionImpl<ELFT>::writeSection(FileOutputBuffer &Out) const { } } +void SymbolTableSection::accept(SectionVisitor &Visitor) const { + Visitor.visit(*this); +} + template <class SymTabType> void RelocSectionWithSymtabBase<SymTabType>::removeSectionReferences( const SectionBase *Sec) { @@ -294,9 +314,8 @@ void setAddend(Elf_Rel_Impl<ELFT, true> &Rela, uint64_t Addend) { Rela.r_addend = Addend; } -template <class ELFT> -template <class T> -void RelocationSection<ELFT>::writeRel(T *Buf) const { +template <class RelRange, class T> +void writeRel(const RelRange &Relocations, T *Buf) { for (const auto &Reloc : Relocations) { Buf->r_offset = Reloc.Offset; setAddend(*Buf, Reloc.Addend); @@ -306,17 +325,25 @@ void RelocationSection<ELFT>::writeRel(T *Buf) const { } template <class ELFT> -void RelocationSection<ELFT>::writeSection(FileOutputBuffer &Out) const { - uint8_t *Buf = Out.getBufferStart() + Offset; - if (Type == SHT_REL) - writeRel(reinterpret_cast<Elf_Rel *>(Buf)); +void ELFSectionWriter<ELFT>::visit(const RelocationSection &Sec) { + uint8_t *Buf = Out.getBufferStart() + Sec.Offset; + if (Sec.Type == SHT_REL) + writeRel(Sec.Relocations, reinterpret_cast<Elf_Rel *>(Buf)); else - writeRel(reinterpret_cast<Elf_Rela *>(Buf)); + writeRel(Sec.Relocations, reinterpret_cast<Elf_Rela *>(Buf)); +} + +void RelocationSection::accept(SectionVisitor &Visitor) const { + Visitor.visit(*this); +} + +void SectionWriter::visit(const DynamicRelocationSection &Sec) { + std::copy(std::begin(Sec.Contents), std::end(Sec.Contents), + Out.getBufferStart() + Sec.Offset); } -void DynamicRelocationSection::writeSection(FileOutputBuffer &Out) const { - std::copy(std::begin(Contents), std::end(Contents), - Out.getBufferStart() + Offset); +void DynamicRelocationSection::accept(SectionVisitor &Visitor) const { + Visitor.visit(*this); } void SectionWithStrTab::removeSectionReferences(const SectionBase *Sec) { @@ -344,8 +371,7 @@ void SectionWithStrTab::initialize(SectionTableRef SecTable) { void SectionWithStrTab::finalize() { this->Link = StrTab->Index; } -template <class ELFT> -void GnuDebugLinkSection<ELFT>::init(StringRef File, StringRef Data) { +void GnuDebugLinkSection::init(StringRef File, StringRef Data) { FileName = sys::path::stem(File); // The format for the .gnu_debuglink starts with the stemmed file name and is // followed by a null terminator and then the CRC32 of the file. The CRC32 @@ -368,9 +394,7 @@ void GnuDebugLinkSection<ELFT>::init(StringRef File, StringRef Data) { CRC32 = ~crc.getCRC(); } -template <class ELFT> -GnuDebugLinkSection<ELFT>::GnuDebugLinkSection(StringRef File) - : FileName(File) { +GnuDebugLinkSection::GnuDebugLinkSection(StringRef File) : FileName(File) { // Read in the file to compute the CRC of it. auto DebugOrErr = MemoryBuffer::getFile(File); if (!DebugOrErr) @@ -380,12 +404,17 @@ GnuDebugLinkSection<ELFT>::GnuDebugLinkSection(StringRef File) } template <class ELFT> -void GnuDebugLinkSection<ELFT>::writeSection(FileOutputBuffer &Out) const { - auto Buf = Out.getBufferStart() + Offset; +void ELFSectionWriter<ELFT>::visit(const GnuDebugLinkSection &Sec) { + auto Buf = Out.getBufferStart() + Sec.Offset; char *File = reinterpret_cast<char *>(Buf); - Elf_Word *CRC = reinterpret_cast<Elf_Word *>(Buf + Size - sizeof(Elf_Word)); - *CRC = CRC32; - std::copy(std::begin(FileName), std::end(FileName), File); + Elf_Word *CRC = + reinterpret_cast<Elf_Word *>(Buf + Sec.Size - sizeof(Elf_Word)); + *CRC = Sec.CRC32; + std::copy(std::begin(Sec.FileName), std::end(Sec.FileName), File); +} + +void GnuDebugLinkSection::accept(SectionVisitor &Visitor) const { + Visitor.visit(*this); } // Returns true IFF a section is wholly inside the range of a segment @@ -427,14 +456,12 @@ static bool compareSegmentsByPAddr(const Segment *A, const Segment *B) { return A->Index < B->Index; } -template <class ELFT> -void Object<ELFT>::readProgramHeaders(const ELFFile<ELFT> &ElfFile) { +template <class ELFT> void ELFBuilder<ELFT>::readProgramHeaders() { uint32_t Index = 0; for (const auto &Phdr : unwrapOrError(ElfFile.program_headers())) { ArrayRef<uint8_t> Data{ElfFile.base() + Phdr.p_offset, (size_t)Phdr.p_filesz}; - Segments.emplace_back(llvm::make_unique<Segment>(Data)); - Segment &Seg = *Segments.back(); + Segment &Seg = Obj.addSegment(Data); Seg.Type = Phdr.p_type; Seg.Flags = Phdr.p_flags; Seg.OriginalOffset = Phdr.p_offset; @@ -445,29 +472,29 @@ void Object<ELFT>::readProgramHeaders(const ELFFile<ELFT> &ElfFile) { Seg.MemSize = Phdr.p_memsz; Seg.Align = Phdr.p_align; Seg.Index = Index++; - for (auto &Section : Sections) { - if (sectionWithinSegment(*Section, Seg)) { - Seg.addSection(&*Section); - if (!Section->ParentSegment || - Section->ParentSegment->Offset > Seg.Offset) { - Section->ParentSegment = &Seg; + for (auto &Section : Obj.sections()) { + if (sectionWithinSegment(Section, Seg)) { + Seg.addSection(&Section); + if (!Section.ParentSegment || + Section.ParentSegment->Offset > Seg.Offset) { + Section.ParentSegment = &Seg; } } } } // Now we do an O(n^2) loop through the segments in order to match up // segments. - for (auto &Child : Segments) { - for (auto &Parent : Segments) { + for (auto &Child : Obj.segments()) { + for (auto &Parent : Obj.segments()) { // Every segment will overlap with itself but we don't want a segment to // be it's own parent so we avoid that situation. - if (&Child != &Parent && segmentOverlapsSegment(*Child, *Parent)) { + if (&Child != &Parent && segmentOverlapsSegment(Child, Parent)) { // We want a canonical "most parental" segment but this requires // inspecting the ParentSegment. - if (compareSegmentsByOffset(Parent.get(), Child.get())) - if (Child->ParentSegment == nullptr || - compareSegmentsByOffset(Parent.get(), Child->ParentSegment)) { - Child->ParentSegment = Parent.get(); + if (compareSegmentsByOffset(&Parent, &Child)) + if (Child.ParentSegment == nullptr || + compareSegmentsByOffset(&Parent, Child.ParentSegment)) { + Child.ParentSegment = &Parent; } } } @@ -475,9 +502,7 @@ void Object<ELFT>::readProgramHeaders(const ELFFile<ELFT> &ElfFile) { } template <class ELFT> -void Object<ELFT>::initSymbolTable(const object::ELFFile<ELFT> &ElfFile, - SymbolTableSection *SymTab, - SectionTableRef SecTable) { +void ELFBuilder<ELFT>::initSymbolTable(SymbolTableSection *SymTab) { const Elf_Shdr &Shdr = *unwrapOrError(ElfFile.getSection(SymTab->Index)); StringRef StrTabData = unwrapOrError(ElfFile.getStringTableForSymtab(Shdr)); @@ -486,14 +511,14 @@ void Object<ELFT>::initSymbolTable(const object::ELFFile<ELFT> &ElfFile, StringRef Name = unwrapOrError(Sym.getName(StrTabData)); if (Sym.st_shndx >= SHN_LORESERVE) { - if (!isValidReservedSectionIndex(Sym.st_shndx, Machine)) { + if (!isValidReservedSectionIndex(Sym.st_shndx, Obj.Machine)) { error( "Symbol '" + Name + "' has unsupported value greater than or equal to SHN_LORESERVE: " + Twine(Sym.st_shndx)); } } else if (Sym.st_shndx != SHN_UNDEF) { - DefSection = SecTable.getSection( + DefSection = Obj.sections().getSection( Sym.st_shndx, "Symbol '" + Name + "' is defined in invalid section with index " + Twine(Sym.st_shndx)); @@ -512,9 +537,9 @@ static void getAddend(uint64_t &ToSet, const Elf_Rel_Impl<ELFT, true> &Rela) { ToSet = Rela.r_addend; } -template <class ELFT, class T> -void initRelocations(RelocationSection<ELFT> *Relocs, - SymbolTableSection *SymbolTable, T RelRange) { +template <class T> +void initRelocations(RelocationSection *Relocs, SymbolTableSection *SymbolTable, + T RelRange) { for (const auto &Rel : RelRange) { Relocation ToAdd; ToAdd.Offset = Rel.r_offset; @@ -540,147 +565,190 @@ T *SectionTableRef::getSectionOfType(uint16_t Index, Twine IndexErrMsg, } template <class ELFT> -std::unique_ptr<SectionBase> -Object<ELFT>::makeSection(const object::ELFFile<ELFT> &ElfFile, - const Elf_Shdr &Shdr) { +SectionBase &ELFBuilder<ELFT>::makeSection(const Elf_Shdr &Shdr) { ArrayRef<uint8_t> Data; switch (Shdr.sh_type) { case SHT_REL: case SHT_RELA: if (Shdr.sh_flags & SHF_ALLOC) { Data = unwrapOrError(ElfFile.getSectionContents(&Shdr)); - return llvm::make_unique<DynamicRelocationSection>(Data); + return Obj.addSection<DynamicRelocationSection>(Data); } - return llvm::make_unique<RelocationSection<ELFT>>(); + return Obj.addSection<RelocationSection>(); case SHT_STRTAB: // If a string table is allocated we don't want to mess with it. That would // mean altering the memory image. There are no special link types or // anything so we can just use a Section. if (Shdr.sh_flags & SHF_ALLOC) { Data = unwrapOrError(ElfFile.getSectionContents(&Shdr)); - return llvm::make_unique<Section>(Data); + return Obj.addSection<Section>(Data); } - return llvm::make_unique<StringTableSection>(); + return Obj.addSection<StringTableSection>(); case SHT_HASH: case SHT_GNU_HASH: // Hash tables should refer to SHT_DYNSYM which we're not going to change. // Because of this we don't need to mess with the hash tables either. Data = unwrapOrError(ElfFile.getSectionContents(&Shdr)); - return llvm::make_unique<Section>(Data); + return Obj.addSection<Section>(Data); case SHT_DYNSYM: Data = unwrapOrError(ElfFile.getSectionContents(&Shdr)); - return llvm::make_unique<DynamicSymbolTableSection>(Data); + return Obj.addSection<DynamicSymbolTableSection>(Data); case SHT_DYNAMIC: Data = unwrapOrError(ElfFile.getSectionContents(&Shdr)); - return llvm::make_unique<DynamicSection>(Data); + return Obj.addSection<DynamicSection>(Data); case SHT_SYMTAB: { - auto SymTab = llvm::make_unique<SymbolTableSectionImpl<ELFT>>(); - SymbolTable = SymTab.get(); - return std::move(SymTab); + auto &SymTab = Obj.addSection<SymbolTableSection>(); + Obj.SymbolTable = &SymTab; + return SymTab; } case SHT_NOBITS: - return llvm::make_unique<Section>(Data); + return Obj.addSection<Section>(Data); default: Data = unwrapOrError(ElfFile.getSectionContents(&Shdr)); - return llvm::make_unique<Section>(Data); + return Obj.addSection<Section>(Data); } } -template <class ELFT> -SectionTableRef Object<ELFT>::readSectionHeaders(const ELFFile<ELFT> &ElfFile) { +template <class ELFT> void ELFBuilder<ELFT>::readSectionHeaders() { uint32_t Index = 0; for (const auto &Shdr : unwrapOrError(ElfFile.sections())) { if (Index == 0) { ++Index; continue; } - SecPtr Sec = makeSection(ElfFile, Shdr); - Sec->Name = unwrapOrError(ElfFile.getSectionName(&Shdr)); - Sec->Type = Shdr.sh_type; - Sec->Flags = Shdr.sh_flags; - Sec->Addr = Shdr.sh_addr; - Sec->Offset = Shdr.sh_offset; - Sec->OriginalOffset = Shdr.sh_offset; - Sec->Size = Shdr.sh_size; - Sec->Link = Shdr.sh_link; - Sec->Info = Shdr.sh_info; - Sec->Align = Shdr.sh_addralign; - Sec->EntrySize = Shdr.sh_entsize; - Sec->Index = Index++; - Sections.push_back(std::move(Sec)); + auto &Sec = makeSection(Shdr); + Sec.Name = unwrapOrError(ElfFile.getSectionName(&Shdr)); + Sec.Type = Shdr.sh_type; + Sec.Flags = Shdr.sh_flags; + Sec.Addr = Shdr.sh_addr; + Sec.Offset = Shdr.sh_offset; + Sec.OriginalOffset = Shdr.sh_offset; + Sec.Size = Shdr.sh_size; + Sec.Link = Shdr.sh_link; + Sec.Info = Shdr.sh_info; + Sec.Align = Shdr.sh_addralign; + Sec.EntrySize = Shdr.sh_entsize; + Sec.Index = Index++; } - SectionTableRef SecTable(Sections); - // Now that all of the sections have been added we can fill out some extra // details about symbol tables. We need the symbol table filled out before // any relocations. - if (SymbolTable) { - SymbolTable->initialize(SecTable); - initSymbolTable(ElfFile, SymbolTable, SecTable); + if (Obj.SymbolTable) { + Obj.SymbolTable->initialize(Obj.sections()); + initSymbolTable(Obj.SymbolTable); } // Now that all sections and symbols have been added we can add // relocations that reference symbols and set the link and info fields for // relocation sections. - for (auto &Section : Sections) { - if (Section.get() == SymbolTable) + for (auto &Section : Obj.sections()) { + if (&Section == Obj.SymbolTable) continue; - Section->initialize(SecTable); - if (auto RelSec = dyn_cast<RelocationSection<ELFT>>(Section.get())) { + Section.initialize(Obj.sections()); + if (auto RelSec = dyn_cast<RelocationSection>(&Section)) { auto Shdr = unwrapOrError(ElfFile.sections()).begin() + RelSec->Index; if (RelSec->Type == SHT_REL) - initRelocations(RelSec, SymbolTable, unwrapOrError(ElfFile.rels(Shdr))); + initRelocations(RelSec, Obj.SymbolTable, + unwrapOrError(ElfFile.rels(Shdr))); else - initRelocations(RelSec, SymbolTable, + initRelocations(RelSec, Obj.SymbolTable, unwrapOrError(ElfFile.relas(Shdr))); } } - - return SecTable; } -template <class ELFT> Object<ELFT>::Object(const ELFObjectFile<ELFT> &Obj) { - const auto &ElfFile = *Obj.getELFFile(); +template <class ELFT> void ELFBuilder<ELFT>::build() { const auto &Ehdr = *ElfFile.getHeader(); - std::copy(Ehdr.e_ident, Ehdr.e_ident + 16, Ident); - Type = Ehdr.e_type; - Machine = Ehdr.e_machine; - Version = Ehdr.e_version; - Entry = Ehdr.e_entry; - Flags = Ehdr.e_flags; - - SectionTableRef SecTable = readSectionHeaders(ElfFile); - readProgramHeaders(ElfFile); - - SectionNames = SecTable.getSectionOfType<StringTableSection>( - Ehdr.e_shstrndx, - "e_shstrndx field value " + Twine(Ehdr.e_shstrndx) + " in elf header " + - " is invalid", - "e_shstrndx field value " + Twine(Ehdr.e_shstrndx) + " in elf header " + - " is not a string table"); + std::copy(Ehdr.e_ident, Ehdr.e_ident + 16, Obj.Ident); + Obj.Type = Ehdr.e_type; + Obj.Machine = Ehdr.e_machine; + Obj.Version = Ehdr.e_version; + Obj.Entry = Ehdr.e_entry; + Obj.Flags = Ehdr.e_flags; + + readSectionHeaders(); + readProgramHeaders(); + + Obj.SectionNames = + Obj.sections().template getSectionOfType<StringTableSection>( + Ehdr.e_shstrndx, + "e_shstrndx field value " + Twine(Ehdr.e_shstrndx) + + " in elf header " + " is invalid", + "e_shstrndx field value " + Twine(Ehdr.e_shstrndx) + + " in elf header " + " is not a string table"); } -template <class ELFT> -void Object<ELFT>::writeHeader(FileOutputBuffer &Out) const { - uint8_t *Buf = Out.getBufferStart(); +// A generic size function which computes sizes of any random access range. +template <class R> size_t size(R &&Range) { + return static_cast<size_t>(std::end(Range) - std::begin(Range)); +} + +Writer::~Writer() {} + +Reader::~Reader() {} + +ELFReader::ELFReader(StringRef File) { + auto BinaryOrErr = createBinary(File); + if (!BinaryOrErr) + reportError(File, BinaryOrErr.takeError()); + auto Bin = std::move(BinaryOrErr.get()); + std::tie(Binary, Data) = Bin.takeBinary(); +} + +ElfType ELFReader::getElfType() const { + if (auto *o = dyn_cast<ELFObjectFile<ELF32LE>>(Binary.get())) + return ELFT_ELF32LE; + if (auto *o = dyn_cast<ELFObjectFile<ELF64LE>>(Binary.get())) + return ELFT_ELF64LE; + if (auto *o = dyn_cast<ELFObjectFile<ELF32BE>>(Binary.get())) + return ELFT_ELF32BE; + if (auto *o = dyn_cast<ELFObjectFile<ELF64BE>>(Binary.get())) + return ELFT_ELF64BE; + llvm_unreachable("Invalid ELFType"); +} + +std::unique_ptr<Object> ELFReader::create() const { + auto Obj = llvm::make_unique<Object>(Data); + if (auto *o = dyn_cast<ELFObjectFile<ELF32LE>>(Binary.get())) { + ELFBuilder<ELF32LE> Builder(*o, *Obj); + Builder.build(); + return Obj; + } else if (auto *o = dyn_cast<ELFObjectFile<ELF64LE>>(Binary.get())) { + ELFBuilder<ELF64LE> Builder(*o, *Obj); + Builder.build(); + return Obj; + } else if (auto *o = dyn_cast<ELFObjectFile<ELF32BE>>(Binary.get())) { + ELFBuilder<ELF32BE> Builder(*o, *Obj); + Builder.build(); + return Obj; + } else if (auto *o = dyn_cast<ELFObjectFile<ELF64BE>>(Binary.get())) { + ELFBuilder<ELF64BE> Builder(*o, *Obj); + Builder.build(); + return Obj; + } + error("Invalid file type"); +} + +template <class ELFT> void ELFWriter<ELFT>::writeEhdr() { + uint8_t *Buf = BufPtr->getBufferStart(); Elf_Ehdr &Ehdr = *reinterpret_cast<Elf_Ehdr *>(Buf); - std::copy(Ident, Ident + 16, Ehdr.e_ident); - Ehdr.e_type = Type; - Ehdr.e_machine = Machine; - Ehdr.e_version = Version; - Ehdr.e_entry = Entry; + std::copy(Obj.Ident, Obj.Ident + 16, Ehdr.e_ident); + Ehdr.e_type = Obj.Type; + Ehdr.e_machine = Obj.Machine; + Ehdr.e_version = Obj.Version; + Ehdr.e_entry = Obj.Entry; Ehdr.e_phoff = sizeof(Elf_Ehdr); - Ehdr.e_flags = Flags; + Ehdr.e_flags = Obj.Flags; Ehdr.e_ehsize = sizeof(Elf_Ehdr); Ehdr.e_phentsize = sizeof(Elf_Phdr); - Ehdr.e_phnum = Segments.size(); + Ehdr.e_phnum = size(Obj.segments()); Ehdr.e_shentsize = sizeof(Elf_Shdr); if (WriteSectionHeaders) { - Ehdr.e_shoff = SHOffset; - Ehdr.e_shnum = Sections.size() + 1; - Ehdr.e_shstrndx = SectionNames->Index; + Ehdr.e_shoff = Obj.SHOffset; + Ehdr.e_shnum = size(Obj.sections()) + 1; + Ehdr.e_shstrndx = Obj.SectionNames->Index; } else { Ehdr.e_shoff = 0; Ehdr.e_shnum = 0; @@ -688,15 +756,13 @@ void Object<ELFT>::writeHeader(FileOutputBuffer &Out) const { } } -template <class ELFT> -void Object<ELFT>::writeProgramHeaders(FileOutputBuffer &Out) const { - for (auto &Phdr : Segments) - Phdr->template writeHeader<ELFT>(Out); +template <class ELFT> void ELFWriter<ELFT>::writePhdrs() { + for (auto &Seg : Obj.segments()) + writePhdr(Seg); } -template <class ELFT> -void Object<ELFT>::writeSectionHeaders(FileOutputBuffer &Out) const { - uint8_t *Buf = Out.getBufferStart() + SHOffset; +template <class ELFT> void ELFWriter<ELFT>::writeShdrs() { + uint8_t *Buf = BufPtr->getBufferStart() + Obj.SHOffset; // This reference serves to write the dummy section header at the begining // of the file. It is not used for anything else Elf_Shdr &Shdr = *reinterpret_cast<Elf_Shdr *>(Buf); @@ -711,19 +777,16 @@ void Object<ELFT>::writeSectionHeaders(FileOutputBuffer &Out) const { Shdr.sh_addralign = 0; Shdr.sh_entsize = 0; - for (auto &Section : Sections) - Section->template writeHeader<ELFT>(Out); + for (auto &Sec : Obj.sections()) + writeShdr(Sec); } -template <class ELFT> -void Object<ELFT>::writeSectionData(FileOutputBuffer &Out) const { - for (auto &Section : Sections) - Section->writeSection(Out); +template <class ELFT> void ELFWriter<ELFT>::writeSectionData() { + for (auto &Sec : Obj.sections()) + Sec.accept(*SecWriter); } -template <class ELFT> -void Object<ELFT>::removeSections( - std::function<bool(const SectionBase &)> ToRemove) { +void Object::removeSections(std::function<bool(const SectionBase &)> ToRemove) { auto Iter = std::stable_partition( std::begin(Sections), std::end(Sections), [=](const SecPtr &Sec) { @@ -737,10 +800,7 @@ void Object<ELFT>::removeSections( }); if (SymbolTable != nullptr && ToRemove(*SymbolTable)) SymbolTable = nullptr; - if (ToRemove(*SectionNames)) { - if (WriteSectionHeaders) - error("Cannot remove " + SectionNames->Name + - " because it is the section header string table."); + if (SectionNames != nullptr && ToRemove(*SectionNames)) { SectionNames = nullptr; } // Now make sure there are no remaining references to the sections that will @@ -756,18 +816,7 @@ void Object<ELFT>::removeSections( Sections.erase(Iter, std::end(Sections)); } -template <class ELFT> -void Object<ELFT>::addSection(StringRef SecName, ArrayRef<uint8_t> Data) { - auto Sec = llvm::make_unique<OwnedDataSection>(SecName, Data); - Sec->OriginalOffset = ~0ULL; - Sections.push_back(std::move(Sec)); -} - -template <class ELFT> void Object<ELFT>::addGnuDebugLink(StringRef File) { - Sections.emplace_back(llvm::make_unique<GnuDebugLinkSection<ELFT>>(File)); -} - -template <class ELFT> void ELFObject<ELFT>::sortSections() { +void Object::sortSections() { // Put all sections in offset order. Maintain the ordering as closely as // possible while meeting that demand however. auto CompareSections = [](const SecPtr &A, const SecPtr &B) { @@ -832,8 +881,8 @@ static uint64_t LayoutSegments(std::vector<Segment *> &Segments, // does not have a ParentSegment. It returns either the offset given if all // sections had a ParentSegment or an offset one past the last section if there // was a section that didn't have a ParentSegment. -template <class SecPtr> -static uint64_t LayoutSections(std::vector<SecPtr> &Sections, uint64_t Offset) { +template <class Range> +static uint64_t LayoutSections(Range Sections, uint64_t Offset) { // Now the offset of every segment has been set we can assign the offsets // of each section. For sections that are covered by a segment we should use // the segment's original offset and the section's original offset to compute @@ -842,28 +891,28 @@ static uint64_t LayoutSections(std::vector<SecPtr> &Sections, uint64_t Offset) { // covered by segments we can just bump Offset to the next valid location. uint32_t Index = 1; for (auto &Section : Sections) { - Section->Index = Index++; - if (Section->ParentSegment != nullptr) { - auto Segment = Section->ParentSegment; - Section->Offset = - Segment->Offset + (Section->OriginalOffset - Segment->OriginalOffset); + Section.Index = Index++; + if (Section.ParentSegment != nullptr) { + auto Segment = *Section.ParentSegment; + Section.Offset = + Segment.Offset + (Section.OriginalOffset - Segment.OriginalOffset); } else { - Offset = alignTo(Offset, Section->Align == 0 ? 1 : Section->Align); - Section->Offset = Offset; - if (Section->Type != SHT_NOBITS) - Offset += Section->Size; + Offset = alignTo(Offset, Section.Align == 0 ? 1 : Section.Align); + Section.Offset = Offset; + if (Section.Type != SHT_NOBITS) + Offset += Section.Size; } } return Offset; } -template <class ELFT> void ELFObject<ELFT>::assignOffsets() { +template <class ELFT> void ELFWriter<ELFT>::assignOffsets() { // We need a temporary list of segments that has a special order to it // so that we know that anytime ->ParentSegment is set that segment has // already had its offset properly set. std::vector<Segment *> OrderedSegments; - for (auto &Segment : this->Segments) - OrderedSegments.push_back(Segment.get()); + for (auto &Segment : Obj.segments()) + OrderedSegments.push_back(&Segment); OrderSegments(OrderedSegments); // The size of ELF + program headers will not change so it is ok to assume // that the first offset of the first segment is a good place to start @@ -876,72 +925,88 @@ template <class ELFT> void ELFObject<ELFT>::assignOffsets() { Offset = sizeof(Elf_Ehdr); } Offset = LayoutSegments(OrderedSegments, Offset); - Offset = LayoutSections(this->Sections, Offset); + Offset = LayoutSections(Obj.sections(), Offset); // If we need to write the section header table out then we need to align the // Offset so that SHOffset is valid. - if (this->WriteSectionHeaders) + if (WriteSectionHeaders) Offset = alignTo(Offset, sizeof(typename ELFT::Addr)); - this->SHOffset = Offset; + Obj.SHOffset = Offset; } -template <class ELFT> size_t ELFObject<ELFT>::totalSize() const { +template <class ELFT> size_t ELFWriter<ELFT>::totalSize() const { // We already have the section header offset so we can calculate the total // size by just adding up the size of each section header. - auto NullSectionSize = this->WriteSectionHeaders ? sizeof(Elf_Shdr) : 0; - return this->SHOffset + this->Sections.size() * sizeof(Elf_Shdr) + + auto NullSectionSize = WriteSectionHeaders ? sizeof(Elf_Shdr) : 0; + return Obj.SHOffset + size(Obj.sections()) * sizeof(Elf_Shdr) + NullSectionSize; } -template <class ELFT> void ELFObject<ELFT>::write(FileOutputBuffer &Out) const { - this->writeHeader(Out); - this->writeProgramHeaders(Out); - this->writeSectionData(Out); - if (this->WriteSectionHeaders) - this->writeSectionHeaders(Out); +template <class ELFT> void ELFWriter<ELFT>::write() { + writeEhdr(); + writePhdrs(); + writeSectionData(); + if (WriteSectionHeaders) + writeShdrs(); + if (auto E = BufPtr->commit()) + reportError(File, errorToErrorCode(std::move(E))); } -template <class ELFT> void ELFObject<ELFT>::finalize() { +void Writer::createBuffer(uint64_t Size) { + auto BufferOrErr = + FileOutputBuffer::create(File, Size, FileOutputBuffer::F_executable); + handleAllErrors(BufferOrErr.takeError(), [this](const ErrorInfoBase &) { + error("failed to open " + File); + }); + BufPtr = std::move(*BufferOrErr); +} + +template <class ELFT> void ELFWriter<ELFT>::finalize() { + // It could happen that SectionNames has been removed and yet the user wants + // a section header table output. We need to throw an error if a user tries + // to do that. + if (Obj.SectionNames == nullptr && WriteSectionHeaders) + error("Cannot write section header table because section header string " + "table was removed."); + // Make sure we add the names of all the sections. - if (this->SectionNames != nullptr) - for (const auto &Section : this->Sections) { - this->SectionNames->addString(Section->Name); + if (Obj.SectionNames != nullptr) + for (const auto &Section : Obj.sections()) { + Obj.SectionNames->addString(Section.Name); } // Make sure we add the names of all the symbols. - if (this->SymbolTable != nullptr) - this->SymbolTable->addSymbolNames(); + if (Obj.SymbolTable != nullptr) + Obj.SymbolTable->addSymbolNames(); - sortSections(); + Obj.sortSections(); assignOffsets(); // Finalize SectionNames first so that we can assign name indexes. - if (this->SectionNames != nullptr) - this->SectionNames->finalize(); + if (Obj.SectionNames != nullptr) + Obj.SectionNames->finalize(); // Finally now that all offsets and indexes have been set we can finalize any // remaining issues. - uint64_t Offset = this->SHOffset + sizeof(Elf_Shdr); - for (auto &Section : this->Sections) { - Section->HeaderOffset = Offset; + uint64_t Offset = Obj.SHOffset + sizeof(Elf_Shdr); + for (auto &Section : Obj.sections()) { + Section.HeaderOffset = Offset; Offset += sizeof(Elf_Shdr); - if (this->WriteSectionHeaders) - Section->NameIndex = this->SectionNames->findIndex(Section->Name); - Section->finalize(); + if (WriteSectionHeaders) + Section.NameIndex = Obj.SectionNames->findIndex(Section.Name); + Section.finalize(); } -} -template <class ELFT> size_t BinaryObject<ELFT>::totalSize() const { - return TotalSize; + createBuffer(totalSize()); + SecWriter = llvm::make_unique<ELFSectionWriter<ELFT>>(*BufPtr); } -template <class ELFT> -void BinaryObject<ELFT>::write(FileOutputBuffer &Out) const { - for (auto &Section : this->Sections) { - if ((Section->Flags & SHF_ALLOC) == 0) +void BinaryWriter::write() { + for (auto &Section : Obj.sections()) { + if ((Section.Flags & SHF_ALLOC) == 0) continue; - Section->writeSection(Out); + Section.accept(*SecWriter); } } -template <class ELFT> void BinaryObject<ELFT>::finalize() { +void BinaryWriter::finalize() { // TODO: Create a filter range to construct OrderedSegments from so that this // code can be deduped with assignOffsets above. This should also solve the // todo below for LayoutSections. @@ -950,10 +1015,9 @@ template <class ELFT> void BinaryObject<ELFT>::finalize() { // already had it's offset properly set. We only want to consider the segments // that will affect layout of allocated sections so we only add those. std::vector<Segment *> OrderedSegments; - for (auto &Section : this->Sections) { - if ((Section->Flags & SHF_ALLOC) != 0 && - Section->ParentSegment != nullptr) { - OrderedSegments.push_back(Section->ParentSegment); + for (auto &Section : Obj.sections()) { + if ((Section.Flags & SHF_ALLOC) != 0 && Section.ParentSegment != nullptr) { + OrderedSegments.push_back(Section.ParentSegment); } } @@ -1004,12 +1068,12 @@ template <class ELFT> void BinaryObject<ELFT>::finalize() { // not hold. Then pass such a range to LayoutSections instead of constructing // AllocatedSections here. std::vector<SectionBase *> AllocatedSections; - for (auto &Section : this->Sections) { - if ((Section->Flags & SHF_ALLOC) == 0) + for (auto &Section : Obj.sections()) { + if ((Section.Flags & SHF_ALLOC) == 0) continue; - AllocatedSections.push_back(Section.get()); + AllocatedSections.push_back(&Section); } - LayoutSections(AllocatedSections, Offset); + LayoutSections(make_pointee_range(AllocatedSections), Offset); // Now that every section has been laid out we just need to compute the total // file size. This might not be the same as the offset returned by @@ -1020,23 +1084,21 @@ template <class ELFT> void BinaryObject<ELFT>::finalize() { if (Section->Type != SHT_NOBITS) TotalSize = std::max(TotalSize, Section->Offset + Section->Size); } + + createBuffer(TotalSize); + SecWriter = llvm::make_unique<BinarySectionWriter>(*BufPtr); } namespace llvm { -template class Object<ELF64LE>; -template class Object<ELF64BE>; -template class Object<ELF32LE>; -template class Object<ELF32BE>; - -template class ELFObject<ELF64LE>; -template class ELFObject<ELF64BE>; -template class ELFObject<ELF32LE>; -template class ELFObject<ELF32BE>; +template class ELFBuilder<ELF64LE>; +template class ELFBuilder<ELF64BE>; +template class ELFBuilder<ELF32LE>; +template class ELFBuilder<ELF32BE>; -template class BinaryObject<ELF64LE>; -template class BinaryObject<ELF64BE>; -template class BinaryObject<ELF32LE>; -template class BinaryObject<ELF32BE>; +template class ELFWriter<ELF64LE>; +template class ELFWriter<ELF64BE>; +template class ELFWriter<ELF32LE>; +template class ELFWriter<ELF32BE>; } // end namespace llvm diff --git a/llvm/tools/llvm-objcopy/Object.h b/llvm/tools/llvm-objcopy/Object.h index 6ac7edd32ae..2c7b572bdab 100644 --- a/llvm/tools/llvm-objcopy/Object.h +++ b/llvm/tools/llvm-objcopy/Object.h @@ -16,6 +16,7 @@ #include "llvm/BinaryFormat/ELF.h" #include "llvm/MC/StringTableBuilder.h" #include "llvm/Object/ELFObjectFile.h" +#include "llvm/Support/FileOutputBuffer.h" #include "llvm/Support/JamCRC.h" #include <cstddef> #include <cstdint> @@ -26,25 +27,159 @@ namespace llvm { -class FileOutputBuffer; class SectionBase; +class Section; +class OwnedDataSection; +class StringTableSection; +class SymbolTableSection; +class RelocationSection; +class DynamicRelocationSection; +class GnuDebugLinkSection; class Segment; +class Object; class SectionTableRef { private: - ArrayRef<std::unique_ptr<SectionBase>> Sections; + MutableArrayRef<std::unique_ptr<SectionBase>> Sections; public: - SectionTableRef(ArrayRef<std::unique_ptr<SectionBase>> Secs) + using iterator = pointee_iterator<std::unique_ptr<SectionBase> *>; + + SectionTableRef(MutableArrayRef<std::unique_ptr<SectionBase>> Secs) : Sections(Secs) {} SectionTableRef(const SectionTableRef &) = default; + iterator begin() { return iterator(Sections.data()); } + iterator end() { return iterator(Sections.data() + Sections.size()); } + SectionBase *getSection(uint16_t Index, Twine ErrMsg); template <class T> T *getSectionOfType(uint16_t Index, Twine IndexErrMsg, Twine TypeErrMsg); }; +enum ElfType { ELFT_ELF32LE, ELFT_ELF64LE, ELFT_ELF32BE, ELFT_ELF64BE }; + +class SectionVisitor { +public: + virtual ~SectionVisitor(); + + virtual void visit(const Section &Sec) = 0; + virtual void visit(const OwnedDataSection &Sec) = 0; + virtual void visit(const StringTableSection &Sec) = 0; + virtual void visit(const SymbolTableSection &Sec) = 0; + virtual void visit(const RelocationSection &Sec) = 0; + virtual void visit(const DynamicRelocationSection &Sec) = 0; + virtual void visit(const GnuDebugLinkSection &Sec) = 0; +}; + +class SectionWriter : public SectionVisitor { +protected: + FileOutputBuffer &Out; + +public: + virtual ~SectionWriter(){}; + + void visit(const Section &Sec) override; + void visit(const OwnedDataSection &Sec) override; + void visit(const StringTableSection &Sec) override; + void visit(const DynamicRelocationSection &Sec) override; + virtual void visit(const SymbolTableSection &Sec) override = 0; + virtual void visit(const RelocationSection &Sec) override = 0; + virtual void visit(const GnuDebugLinkSection &Sec) override = 0; + + SectionWriter(FileOutputBuffer &Buf) : Out(Buf) {} +}; + +template <class ELFT> class ELFSectionWriter : public SectionWriter { +private: + using Elf_Word = typename ELFT::Word; + using Elf_Rel = typename ELFT::Rel; + using Elf_Rela = typename ELFT::Rela; + +public: + virtual ~ELFSectionWriter() {} + void visit(const SymbolTableSection &Sec) override; + void visit(const RelocationSection &Sec) override; + void visit(const GnuDebugLinkSection &Sec) override; + + ELFSectionWriter(FileOutputBuffer &Buf) : SectionWriter(Buf) {} +}; + +#define MAKE_SEC_WRITER_FRIEND \ + friend class SectionWriter; \ + template <class ELFT> friend class ELFSectionWriter; + +class BinarySectionWriter : public SectionWriter { +public: + virtual ~BinarySectionWriter() {} + + void visit(const SymbolTableSection &Sec) override; + void visit(const RelocationSection &Sec) override; + void visit(const GnuDebugLinkSection &Sec) override; + BinarySectionWriter(FileOutputBuffer &Buf) : SectionWriter(Buf) {} +}; + +class Writer { +protected: + StringRef File; + Object &Obj; + std::unique_ptr<FileOutputBuffer> BufPtr; + + void createBuffer(uint64_t Size); + +public: + virtual ~Writer(); + + virtual void finalize() = 0; + virtual void write() = 0; + + Writer(StringRef File, Object &Obj) : File(File), Obj(Obj) {} +}; + +template <class ELFT> class ELFWriter : public Writer { +private: + using Elf_Shdr = typename ELFT::Shdr; + using Elf_Phdr = typename ELFT::Phdr; + using Elf_Ehdr = typename ELFT::Ehdr; + + void writeEhdr(); + void writePhdr(const Segment &Seg); + void writeShdr(const SectionBase &Sec); + + void writePhdrs(); + void writeShdrs(); + void writeSectionData(); + + void assignOffsets(); + + std::unique_ptr<ELFSectionWriter<ELFT>> SecWriter; + + size_t totalSize() const; + +public: + virtual ~ELFWriter() {} + bool WriteSectionHeaders = true; + + void finalize() override; + void write() override; + ELFWriter(StringRef File, Object &Obj, bool WSH) + : Writer(File, Obj), WriteSectionHeaders(WSH) {} +}; + +class BinaryWriter : public Writer { +private: + std::unique_ptr<BinarySectionWriter> SecWriter; + + uint64_t TotalSize; + +public: + ~BinaryWriter() {} + void finalize() override; + void write() override; + BinaryWriter(StringRef File, Object &Obj) : Writer(File, Obj) {} +}; + class SectionBase { public: StringRef Name; @@ -69,8 +204,7 @@ public: virtual void initialize(SectionTableRef SecTable); virtual void finalize(); virtual void removeSectionReferences(const SectionBase *Sec); - template <class ELFT> void writeHeader(FileOutputBuffer &Out) const; - virtual void writeSection(FileOutputBuffer &Out) const = 0; + virtual void accept(SectionVisitor &Visitor) const = 0; }; class Segment { @@ -113,21 +247,23 @@ public: void removeSection(const SectionBase *Sec) { Sections.erase(Sec); } void addSection(const SectionBase *Sec) { Sections.insert(Sec); } - template <class ELFT> void writeHeader(FileOutputBuffer &Out) const; - void writeSegment(FileOutputBuffer &Out) const; }; class Section : public SectionBase { + MAKE_SEC_WRITER_FRIEND + private: ArrayRef<uint8_t> Contents; public: Section(ArrayRef<uint8_t> Data) : Contents(Data) {} - void writeSection(FileOutputBuffer &Out) const override; + void accept(SectionVisitor &Visitor) const override; }; class OwnedDataSection : public SectionBase { + MAKE_SEC_WRITER_FRIEND + private: std::vector<uint8_t> Data; @@ -137,8 +273,10 @@ public: Name = SecName; Type = ELF::SHT_PROGBITS; Size = Data.size(); + OriginalOffset = std::numeric_limits<uint64_t>::max(); } - void writeSection(FileOutputBuffer &Out) const override; + + void accept(SectionVisitor &Sec) const override; }; // There are two types of string tables that can exist, dynamic and not dynamic. @@ -150,6 +288,8 @@ public: // classof method checks that the particular instance is not allocated. This // then agrees with the makeSection method used to construct most sections. class StringTableSection : public SectionBase { + MAKE_SEC_WRITER_FRIEND + private: StringTableBuilder StrTabBuilder; @@ -161,7 +301,7 @@ public: void addString(StringRef Name); uint32_t findIndex(StringRef Name) const; void finalize() override; - void writeSection(FileOutputBuffer &Out) const override; + void accept(SectionVisitor &Visitor) const override; static bool classof(const SectionBase *S) { if (S->Flags & ELF::SHF_ALLOC) @@ -200,6 +340,8 @@ struct Symbol { }; class SymbolTableSection : public SectionBase { + MAKE_SEC_WRITER_FRIEND + protected: std::vector<std::unique_ptr<Symbol>> Symbols; StringTableSection *SymbolNames = nullptr; @@ -218,17 +360,13 @@ public: void localize(std::function<bool(const Symbol &)> ToLocalize); void initialize(SectionTableRef SecTable) override; void finalize() override; + void accept(SectionVisitor &Visitor) const override; static bool classof(const SectionBase *S) { return S->Type == ELF::SHT_SYMTAB; } }; -// Only writeSection depends on the ELF type so we implement it in a subclass. -template <class ELFT> class SymbolTableSectionImpl : public SymbolTableSection { - void writeSection(FileOutputBuffer &Out) const override; -}; - struct Relocation { const Symbol *RelocSymbol = nullptr; uint64_t Offset; @@ -275,20 +413,16 @@ public: void finalize() override; }; -template <class ELFT> class RelocationSection : public RelocSectionWithSymtabBase<SymbolTableSection> { -private: - using Elf_Rel = typename ELFT::Rel; - using Elf_Rela = typename ELFT::Rela; + MAKE_SEC_WRITER_FRIEND +private: std::vector<Relocation> Relocations; - template <class T> void writeRel(T *Buf) const; - public: void addRelocation(Relocation Rel) { Relocations.push_back(Rel); } - void writeSection(FileOutputBuffer &Out) const override; + void accept(SectionVisitor &Visitor) const override; static bool classof(const SectionBase *S) { if (S->Flags & ELF::SHF_ALLOC) @@ -331,13 +465,15 @@ public: class DynamicRelocationSection : public RelocSectionWithSymtabBase<DynamicSymbolTableSection> { + MAKE_SEC_WRITER_FRIEND + private: ArrayRef<uint8_t> Contents; public: DynamicRelocationSection(ArrayRef<uint8_t> Data) : Contents(Data) {} - void writeSection(FileOutputBuffer &Out) const override; + void accept(SectionVisitor &) const override; static bool classof(const SectionBase *S) { if (!(S->Flags & ELF::SHF_ALLOC)) @@ -346,12 +482,10 @@ public: } }; -template <class ELFT> class GnuDebugLinkSection : public SectionBase { +class GnuDebugLinkSection : public SectionBase { + MAKE_SEC_WRITER_FRIEND + private: - // Elf_Word is 4-bytes on every format but has the same endianess as the elf - // type ELFT. We'll need to write the CRC32 out in the proper endianess so - // we'll make sure to use this type. - using Elf_Word = typename ELFT::Word; StringRef FileName; uint32_t CRC32; @@ -361,92 +495,101 @@ private: public: // If we add this section from an external source we can use this ctor. GnuDebugLinkSection(StringRef File); - void writeSection(FileOutputBuffer &Out) const override; + void accept(SectionVisitor &Visitor) const override; }; -template <class ELFT> class Object { -private: - using SecPtr = std::unique_ptr<SectionBase>; - using SegPtr = std::unique_ptr<Segment>; +class Reader { +public: + virtual ~Reader(); + virtual std::unique_ptr<Object> create() const = 0; +}; + +using object::OwningBinary; +using object::Binary; +using object::ELFFile; +using object::ELFObjectFile; +template <class ELFT> class ELFBuilder { +private: using Elf_Shdr = typename ELFT::Shdr; - using Elf_Ehdr = typename ELFT::Ehdr; - using Elf_Phdr = typename ELFT::Phdr; - void initSymbolTable(const object::ELFFile<ELFT> &ElfFile, - SymbolTableSection *SymTab, SectionTableRef SecTable); - SecPtr makeSection(const object::ELFFile<ELFT> &ElfFile, - const Elf_Shdr &Shdr); - void readProgramHeaders(const object::ELFFile<ELFT> &ElfFile); - SectionTableRef readSectionHeaders(const object::ELFFile<ELFT> &ElfFile); + const ELFFile<ELFT> &ElfFile; + Object &Obj; -protected: - StringTableSection *SectionNames = nullptr; - SymbolTableSection *SymbolTable = nullptr; - std::vector<SecPtr> Sections; - std::vector<SegPtr> Segments; - - void writeHeader(FileOutputBuffer &Out) const; - void writeProgramHeaders(FileOutputBuffer &Out) const; - void writeSectionData(FileOutputBuffer &Out) const; - void writeSectionHeaders(FileOutputBuffer &Out) const; + void readProgramHeaders(); + void initSymbolTable(SymbolTableSection *SymTab); + void readSectionHeaders(); + SectionBase &makeSection(const Elf_Shdr &Shdr); public: - uint8_t Ident[16]; - uint64_t Entry; - uint64_t SHOffset; - uint32_t Type; - uint32_t Machine; - uint32_t Version; - uint32_t Flags; - bool WriteSectionHeaders = true; - - Object(const object::ELFObjectFile<ELFT> &Obj); - virtual ~Object() = default; + ELFBuilder(const ELFObjectFile<ELFT> &ElfObj, Object &Obj) + : ElfFile(*ElfObj.getELFFile()), Obj(Obj) {} - SymbolTableSection *getSymTab() const { return SymbolTable; } - const SectionBase *getSectionHeaderStrTab() const { return SectionNames; } - void removeSections(std::function<bool(const SectionBase &)> ToRemove); - void addSection(StringRef SecName, ArrayRef<uint8_t> Data); - void addGnuDebugLink(StringRef File); - virtual size_t totalSize() const = 0; - virtual void finalize() = 0; - virtual void write(FileOutputBuffer &Out) const = 0; + void build(); }; -template <class ELFT> class ELFObject : public Object<ELFT> { +class ELFReader : public Reader { private: - using SecPtr = std::unique_ptr<SectionBase>; - using SegPtr = std::unique_ptr<Segment>; - - using Elf_Shdr = typename ELFT::Shdr; - using Elf_Ehdr = typename ELFT::Ehdr; - using Elf_Phdr = typename ELFT::Phdr; - - void sortSections(); - void assignOffsets(); + std::unique_ptr<Binary> Binary; + std::shared_ptr<MemoryBuffer> Data; public: - ELFObject(const object::ELFObjectFile<ELFT> &Obj) : Object<ELFT>(Obj) {} - - void finalize() override; - size_t totalSize() const override; - void write(FileOutputBuffer &Out) const override; + ElfType getElfType() const; + std::unique_ptr<Object> create() const override; + ELFReader(StringRef File); }; -template <class ELFT> class BinaryObject : public Object<ELFT> { +class Object { private: using SecPtr = std::unique_ptr<SectionBase>; using SegPtr = std::unique_ptr<Segment>; - uint64_t TotalSize; + std::shared_ptr<MemoryBuffer> OwnedData; + std::vector<SecPtr> Sections; + std::vector<SegPtr> Segments; public: - BinaryObject(const object::ELFObjectFile<ELFT> &Obj) : Object<ELFT>(Obj) {} + template <class T> + using Range = iterator_range< + pointee_iterator<typename std::vector<std::unique_ptr<T>>::iterator>>; - void finalize() override; - size_t totalSize() const override; - void write(FileOutputBuffer &Out) const override; + template <class T> + using ConstRange = iterator_range<pointee_iterator< + typename std::vector<std::unique_ptr<T>>::const_iterator>>; + + uint8_t Ident[16]; + uint64_t Entry; + uint64_t SHOffset; + uint32_t Type; + uint32_t Machine; + uint32_t Version; + uint32_t Flags; + + StringTableSection *SectionNames = nullptr; + SymbolTableSection *SymbolTable = nullptr; + + Object(std::shared_ptr<MemoryBuffer> Data) : OwnedData(Data) {} + virtual ~Object() = default; + + void sortSections(); + SectionTableRef sections() { return SectionTableRef(Sections); } + ConstRange<SectionBase> sections() const { + return make_pointee_range(Sections); + } + Range<Segment> segments() { return make_pointee_range(Segments); } + ConstRange<Segment> segments() const { return make_pointee_range(Segments); } + + void removeSections(std::function<bool(const SectionBase &)> ToRemove); + template <class T, class... Ts> T &addSection(Ts &&... Args) { + auto Sec = llvm::make_unique<T>(std::forward<Ts>(Args)...); + auto Ptr = Sec.get(); + Sections.emplace_back(std::move(Sec)); + return *Ptr; + } + Segment &addSegment(ArrayRef<uint8_t> Data) { + Segments.emplace_back(llvm::make_unique<Segment>(Data)); + return *Segments.back(); + } }; } // end namespace llvm diff --git a/llvm/tools/llvm-objcopy/llvm-objcopy.cpp b/llvm/tools/llvm-objcopy/llvm-objcopy.cpp index 0b09184497d..8f5243cefa0 100644 --- a/llvm/tools/llvm-objcopy/llvm-objcopy.cpp +++ b/llvm/tools/llvm-objcopy/llvm-objcopy.cpp @@ -130,42 +130,42 @@ using SectionPred = std::function<bool(const SectionBase &Sec)>; bool IsDWOSection(const SectionBase &Sec) { return Sec.Name.endswith(".dwo"); } -template <class ELFT> -bool OnlyKeepDWOPred(const Object<ELFT> &Obj, const SectionBase &Sec) { +bool OnlyKeepDWOPred(const Object &Obj, const SectionBase &Sec) { // We can't remove the section header string table. - if (&Sec == Obj.getSectionHeaderStrTab()) + if (&Sec == Obj.SectionNames) return false; // Short of keeping the string table we want to keep everything that is a DWO // section and remove everything else. return !IsDWOSection(Sec); } -template <class ELFT> -void WriteObjectFile(const Object<ELFT> &Obj, StringRef File) { - std::unique_ptr<FileOutputBuffer> Buffer; - Expected<std::unique_ptr<FileOutputBuffer>> BufferOrErr = - FileOutputBuffer::create(File, Obj.totalSize(), - FileOutputBuffer::F_executable); - handleAllErrors(BufferOrErr.takeError(), [](const ErrorInfoBase &) { - error("failed to open " + OutputFilename); - }); - Buffer = std::move(*BufferOrErr); - - Obj.write(*Buffer); - if (auto E = Buffer->commit()) - reportError(File, errorToErrorCode(std::move(E))); -} +static ElfType OutputElfType; -template <class ELFT> -void SplitDWOToFile(const ELFObjectFile<ELFT> &ObjFile, StringRef File) { - // Construct a second output file for the DWO sections. - ELFObject<ELFT> DWOFile(ObjFile); +std::unique_ptr<Writer> CreateWriter(Object &Obj, StringRef File) { + if (OutputFormat == "binary") { + return llvm::make_unique<BinaryWriter>(OutputFilename, Obj); + } + // Depending on the initial ELFT and OutputFormat we need a different Writer. + switch (OutputElfType) { + case ELFT_ELF32LE: + return llvm::make_unique<ELFWriter<ELF32LE>>(File, Obj, !StripSections); + case ELFT_ELF64LE: + return llvm::make_unique<ELFWriter<ELF64LE>>(File, Obj, !StripSections); + case ELFT_ELF32BE: + return llvm::make_unique<ELFWriter<ELF32BE>>(File, Obj, !StripSections); + case ELFT_ELF64BE: + return llvm::make_unique<ELFWriter<ELF64BE>>(File, Obj, !StripSections); + } + llvm_unreachable("Invalid output format"); +} - DWOFile.removeSections([&](const SectionBase &Sec) { - return OnlyKeepDWOPred<ELFT>(DWOFile, Sec); - }); - DWOFile.finalize(); - WriteObjectFile(DWOFile, File); +void SplitDWOToFile(const Reader &Reader, StringRef File) { + auto DWOFile = Reader.create(); + DWOFile->removeSections( + [&](const SectionBase &Sec) { return OnlyKeepDWOPred(*DWOFile, Sec); }); + auto Writer = CreateWriter(*DWOFile, File); + Writer->finalize(); + Writer->write(); } // This function handles the high level operations of GNU objcopy including @@ -175,23 +175,16 @@ void SplitDWOToFile(const ELFObjectFile<ELFT> &ObjFile, StringRef File) { // any previous removals. Lastly whether or not something is removed shouldn't // depend a) on the order the options occur in or b) on some opaque priority // system. The only priority is that keeps/copies overrule removes. -template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { - std::unique_ptr<Object<ELFT>> Obj; - - if (!OutputFormat.empty() && OutputFormat != "binary") - error("invalid output format '" + OutputFormat + "'"); - if (!OutputFormat.empty() && OutputFormat == "binary") - Obj = llvm::make_unique<BinaryObject<ELFT>>(ObjFile); - else - Obj = llvm::make_unique<ELFObject<ELFT>>(ObjFile); +void HandleArgs(Object &Obj, const Reader &Reader) { - if (!SplitDWO.empty()) - SplitDWOToFile<ELFT>(ObjFile, SplitDWO.getValue()); + if (!SplitDWO.empty()) { + SplitDWOToFile(Reader, SplitDWO); + } // Localize: if (LocalizeHidden) { - Obj->getSymTab()->localize([](const Symbol &Sym) { + Obj.SymbolTable->localize([](const Symbol &Sym) { return Sym.Visibility == STV_HIDDEN || Sym.Visibility == STV_INTERNAL; }); } @@ -214,7 +207,7 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { if (ExtractDWO) RemovePred = [RemovePred, &Obj](const SectionBase &Sec) { - return OnlyKeepDWOPred(*Obj, Sec) || RemovePred(Sec); + return OnlyKeepDWOPred(Obj, Sec) || RemovePred(Sec); }; if (StripAllGNU) @@ -223,7 +216,7 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { return true; if ((Sec.Flags & SHF_ALLOC) != 0) return false; - if (&Sec == Obj->getSectionHeaderStrTab()) + if (&Sec == Obj.SectionNames) return false; switch (Sec.Type) { case SHT_SYMTAB: @@ -239,7 +232,6 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { RemovePred = [RemovePred](const SectionBase &Sec) { return RemovePred(Sec) || (Sec.Flags & SHF_ALLOC) == 0; }; - Obj->WriteSectionHeaders = false; } if (StripDebug) { @@ -252,7 +244,7 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { RemovePred = [RemovePred, &Obj](const SectionBase &Sec) { if (RemovePred(Sec)) return true; - if (&Sec == Obj->getSectionHeaderStrTab()) + if (&Sec == Obj.SectionNames) return false; return (Sec.Flags & SHF_ALLOC) == 0; }; @@ -261,7 +253,7 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { RemovePred = [RemovePred, &Obj](const SectionBase &Sec) { if (RemovePred(Sec)) return true; - if (&Sec == Obj->getSectionHeaderStrTab()) + if (&Sec == Obj.SectionNames) return false; if (Sec.Name.startswith(".gnu.warning")) return false; @@ -278,17 +270,15 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { return false; // Allow all implicit removes. - if (RemovePred(Sec)) { + if (RemovePred(Sec)) return true; - } // Keep special sections. - if (Obj->getSectionHeaderStrTab() == &Sec) { + if (Obj.SectionNames == &Sec) return false; - } - if (Obj->getSymTab() == &Sec || Obj->getSymTab()->getStrTab() == &Sec) { + if (Obj.SymbolTable == &Sec || Obj.SymbolTable->getStrTab() == &Sec) return false; - } + // Remove everything else. return true; }; @@ -305,7 +295,7 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { }; } - Obj->removeSections(RemovePred); + Obj.removeSections(RemovePred); if (!AddSection.empty()) { for (const auto &Flag : AddSection) { @@ -318,16 +308,22 @@ template <class ELFT> void CopyBinary(const ELFObjectFile<ELFT> &ObjFile) { auto Buf = std::move(*BufOrErr); auto BufPtr = reinterpret_cast<const uint8_t *>(Buf->getBufferStart()); auto BufSize = Buf->getBufferSize(); - Obj->addSection(SecName, ArrayRef<uint8_t>(BufPtr, BufSize)); + Obj.addSection<OwnedDataSection>(SecName, + ArrayRef<uint8_t>(BufPtr, BufSize)); } } if (!AddGnuDebugLink.empty()) { - Obj->addGnuDebugLink(AddGnuDebugLink); + Obj.addSection<GnuDebugLinkSection>(StringRef(AddGnuDebugLink)); } +} - Obj->finalize(); - WriteObjectFile(*Obj, OutputFilename.getValue()); +std::unique_ptr<Reader> CreateReader() { + // Right now we can only read ELF files so there's only one reader; + auto Out = llvm::make_unique<ELFReader>(StringRef(InputFilename)); + // We need to set the default ElfType for output. + OutputElfType = Out->getElfType(); + return std::move(Out); } int main(int argc, char **argv) { @@ -341,25 +337,11 @@ int main(int argc, char **argv) { cl::PrintHelpMessage(); return 2; } - Expected<OwningBinary<Binary>> BinaryOrErr = createBinary(InputFilename); - if (!BinaryOrErr) - reportError(InputFilename, BinaryOrErr.takeError()); - Binary &Binary = *BinaryOrErr.get().getBinary(); - if (auto *o = dyn_cast<ELFObjectFile<ELF64LE>>(&Binary)) { - CopyBinary(*o); - return 0; - } - if (auto *o = dyn_cast<ELFObjectFile<ELF32LE>>(&Binary)) { - CopyBinary(*o); - return 0; - } - if (auto *o = dyn_cast<ELFObjectFile<ELF64BE>>(&Binary)) { - CopyBinary(*o); - return 0; - } - if (auto *o = dyn_cast<ELFObjectFile<ELF32BE>>(&Binary)) { - CopyBinary(*o); - return 0; - } - reportError(InputFilename, object_error::invalid_file_type); + + auto Reader = CreateReader(); + auto Obj = Reader->create(); + auto Writer = CreateWriter(*Obj, OutputFilename); + HandleArgs(*Obj, *Reader); + Writer->finalize(); + Writer->write(); } diff --git a/llvm/tools/llvm-objcopy/llvm-objcopy.h b/llvm/tools/llvm-objcopy/llvm-objcopy.h index 6732e410d8e..10b083ecaee 100644 --- a/llvm/tools/llvm-objcopy/llvm-objcopy.h +++ b/llvm/tools/llvm-objcopy/llvm-objcopy.h @@ -19,6 +19,9 @@ namespace llvm { LLVM_ATTRIBUTE_NORETURN extern void error(Twine Message); +LLVM_ATTRIBUTE_NORETURN extern void reportError(StringRef File, Error E); +LLVM_ATTRIBUTE_NORETURN extern void reportError(StringRef File, + std::error_code EC); // This is taken from llvm-readobj. // [see here](llvm/tools/llvm-readobj/llvm-readobj.h:38) |