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Diffstat (limited to 'compiler/elf_writer_quick.cc')
-rw-r--r-- | compiler/elf_writer_quick.cc | 665 |
1 files changed, 665 insertions, 0 deletions
diff --git a/compiler/elf_writer_quick.cc b/compiler/elf_writer_quick.cc new file mode 100644 index 0000000..9de96d2 --- /dev/null +++ b/compiler/elf_writer_quick.cc @@ -0,0 +1,665 @@ +/* + * Copyright (C) 2012 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "elf_writer_quick.h" + +#include "base/logging.h" +#include "base/unix_file/fd_file.h" +#include "driver/compiler_driver.h" +#include "globals.h" +#include "oat.h" +#include "utils.h" + +namespace art { + +ElfWriterQuick::ElfWriterQuick(const CompilerDriver& driver, File* elf_file) + : ElfWriter(driver, elf_file) {} + +ElfWriterQuick::~ElfWriterQuick() {} + +bool ElfWriterQuick::Create(File* elf_file, + std::vector<uint8_t>& oat_contents, + const std::vector<const DexFile*>& dex_files, + const std::string& android_root, + bool is_host, + const CompilerDriver& driver) { + ElfWriterQuick elf_writer(driver, elf_file); + return elf_writer.Write(oat_contents, dex_files, android_root, is_host); +} + +bool ElfWriterQuick::Write(std::vector<uint8_t>& oat_contents, + const std::vector<const DexFile*>& dex_files_unused, + const std::string& android_root_unused, + bool is_host_unused) { + const bool debug = false; + // +-------------------------+ + // | Elf32_Ehdr | + // +-------------------------+ + // | Elf32_Phdr PHDR | + // | Elf32_Phdr LOAD R | .dynsym .dynstr .hash .rodata + // | Elf32_Phdr LOAD R X | .text + // | Elf32_Phdr LOAD RW | .dynamic + // | Elf32_Phdr DYNAMIC | .dynamic + // +-------------------------+ + // | .dynsym | + // | Elf32_Sym STN_UNDEF | + // | Elf32_Sym oatdata | + // | Elf32_Sym oatexec | + // | Elf32_Sym oatlastword | + // +-------------------------+ + // | .dynstr | + // | \0 | + // | oatdata\0 | + // | oatexec\0 | + // | oatlastword\0 | + // | boot.oat\0 | + // +-------------------------+ + // | .hash | + // | Elf32_Word nbucket = 1 | + // | Elf32_Word nchain = 3 | + // | Elf32_Word bucket[0] = 0| + // | Elf32_Word chain[0] = 1| + // | Elf32_Word chain[1] = 2| + // | Elf32_Word chain[2] = 3| + // +-------------------------+ + // | .rodata | + // | oatdata..oatexec-4 | + // +-------------------------+ + // | .text | + // | oatexec..oatlastword | + // +-------------------------+ + // | .dynamic | + // | Elf32_Dyn DT_SONAME | + // | Elf32_Dyn DT_HASH | + // | Elf32_Dyn DT_SYMTAB | + // | Elf32_Dyn DT_SYMENT | + // | Elf32_Dyn DT_STRTAB | + // | Elf32_Dyn DT_STRSZ | + // | Elf32_Dyn DT_NULL | + // +-------------------------+ + // | .shstrtab | + // | \0 | + // | .dynamic\0 | + // | .dynsym\0 | + // | .dynstr\0 | + // | .hash\0 | + // | .rodata\0 | + // | .text\0 | + // | .shstrtab\0 | + // +-------------------------+ + // | Elf32_Shdr NULL | + // | Elf32_Shdr .dynsym | + // | Elf32_Shdr .dynstr | + // | Elf32_Shdr .hash | + // | Elf32_Shdr .text | + // | Elf32_Shdr .rodata | + // | Elf32_Shdr .dynamic | + // | Elf32_Shdr .shstrtab | + // +-------------------------+ + + // phase 1: computing offsets + uint32_t expected_offset = 0; + + // Elf32_Ehdr + expected_offset += sizeof(llvm::ELF::Elf32_Ehdr); + + // PHDR + uint32_t phdr_alignment = sizeof(llvm::ELF::Elf32_Word); + uint32_t phdr_offset = expected_offset; + const uint8_t PH_PHDR = 0; + const uint8_t PH_LOAD_R__ = 1; + const uint8_t PH_LOAD_R_X = 2; + const uint8_t PH_LOAD_RW_ = 3; + const uint8_t PH_DYNAMIC = 4; + const uint8_t PH_NUM = 5; + uint32_t phdr_size = sizeof(llvm::ELF::Elf32_Phdr) * PH_NUM; + expected_offset += phdr_size; + if (debug) { + LOG(INFO) << "phdr_offset=" << phdr_offset << std::hex << " " << phdr_offset; + LOG(INFO) << "phdr_size=" << phdr_size << std::hex << " " << phdr_size; + } + + // .dynsym + uint32_t dynsym_alignment = sizeof(llvm::ELF::Elf32_Word); + uint32_t dynsym_offset = expected_offset = RoundUp(expected_offset, dynsym_alignment); + const uint8_t SYM_UNDEF = 0; // aka STN_UNDEF + const uint8_t SYM_OATDATA = 1; + const uint8_t SYM_OATEXEC = 2; + const uint8_t SYM_OATLASTWORD = 3; + const uint8_t SYM_NUM = 4; + uint32_t dynsym_size = sizeof(llvm::ELF::Elf32_Sym) * SYM_NUM; + expected_offset += dynsym_size; + if (debug) { + LOG(INFO) << "dynsym_offset=" << dynsym_offset << std::hex << " " << dynsym_offset; + LOG(INFO) << "dynsym_size=" << dynsym_size << std::hex << " " << dynsym_size; + } + + // .dynstr + uint32_t dynstr_alignment = 1; + uint32_t dynstr_offset = expected_offset = RoundUp(expected_offset, dynstr_alignment); + std::string dynstr; + dynstr += '\0'; + uint32_t dynstr_oatdata_offset = dynstr.size(); + dynstr += "oatdata"; + dynstr += '\0'; + uint32_t dynstr_oatexec_offset = dynstr.size(); + dynstr += "oatexec"; + dynstr += '\0'; + uint32_t dynstr_oatlastword_offset = dynstr.size(); + dynstr += "oatlastword"; + dynstr += '\0'; + uint32_t dynstr_soname_offset = dynstr.size(); + std::string file_name(elf_file_->GetPath()); + size_t directory_separator_pos = file_name.rfind('/'); + if (directory_separator_pos != std::string::npos) { + file_name = file_name.substr(directory_separator_pos + 1); + } + dynstr += file_name; + dynstr += '\0'; + uint32_t dynstr_size = dynstr.size(); + expected_offset += dynstr_size; + if (debug) { + LOG(INFO) << "dynstr_offset=" << dynstr_offset << std::hex << " " << dynstr_offset; + LOG(INFO) << "dynstr_size=" << dynstr_size << std::hex << " " << dynstr_size; + } + + // .hash + uint32_t hash_alignment = sizeof(llvm::ELF::Elf32_Word); // Even for 64-bit + uint32_t hash_offset = expected_offset = RoundUp(expected_offset, hash_alignment); + const uint8_t HASH_NBUCKET = 0; + const uint8_t HASH_NCHAIN = 1; + const uint8_t HASH_BUCKET0 = 2; + const uint8_t HASH_NUM = HASH_BUCKET0 + 1 + SYM_NUM; + uint32_t hash_size = sizeof(llvm::ELF::Elf32_Word) * HASH_NUM; + expected_offset += hash_size; + if (debug) { + LOG(INFO) << "hash_offset=" << hash_offset << std::hex << " " << hash_offset; + LOG(INFO) << "hash_size=" << hash_size << std::hex << " " << hash_size; + } + + // .rodata + uint32_t oat_data_alignment = kPageSize; + uint32_t oat_data_offset = expected_offset = RoundUp(expected_offset, oat_data_alignment); + const OatHeader* oat_header = reinterpret_cast<OatHeader*>(&oat_contents[0]); + CHECK(oat_header->IsValid()); + uint32_t oat_data_size = oat_header->GetExecutableOffset(); + expected_offset += oat_data_size; + if (debug) { + LOG(INFO) << "oat_data_offset=" << oat_data_offset << std::hex << " " << oat_data_offset; + LOG(INFO) << "oat_data_size=" << oat_data_size << std::hex << " " << oat_data_size; + } + + // .text + uint32_t oat_exec_alignment = kPageSize; + CHECK_ALIGNED(expected_offset, kPageSize); + uint32_t oat_exec_offset = expected_offset = RoundUp(expected_offset, oat_exec_alignment); + uint32_t oat_exec_size = oat_contents.size() - oat_data_size; + expected_offset += oat_exec_size; + CHECK_EQ(oat_data_offset + oat_contents.size(), expected_offset); + if (debug) { + LOG(INFO) << "oat_exec_offset=" << oat_exec_offset << std::hex << " " << oat_exec_offset; + LOG(INFO) << "oat_exec_size=" << oat_exec_size << std::hex << " " << oat_exec_size; + } + + // .dynamic + // alignment would naturally be sizeof(llvm::ELF::Elf32_Word), but we want this in a new segment + uint32_t dynamic_alignment = kPageSize; + uint32_t dynamic_offset = expected_offset = RoundUp(expected_offset, dynamic_alignment); + const uint8_t DH_SONAME = 0; + const uint8_t DH_HASH = 1; + const uint8_t DH_SYMTAB = 2; + const uint8_t DH_SYMENT = 3; + const uint8_t DH_STRTAB = 4; + const uint8_t DH_STRSZ = 5; + const uint8_t DH_NULL = 6; + const uint8_t DH_NUM = 7; + uint32_t dynamic_size = sizeof(llvm::ELF::Elf32_Dyn) * DH_NUM; + expected_offset += dynamic_size; + if (debug) { + LOG(INFO) << "dynamic_offset=" << dynamic_offset << std::hex << " " << dynamic_offset; + LOG(INFO) << "dynamic_size=" << dynamic_size << std::hex << " " << dynamic_size; + } + + // .shstrtab + uint32_t shstrtab_alignment = 1; + uint32_t shstrtab_offset = expected_offset = RoundUp(expected_offset, shstrtab_alignment); + std::string shstrtab; + shstrtab += '\0'; + uint32_t shstrtab_dynamic_offset = shstrtab.size(); + CHECK_EQ(1U, shstrtab_dynamic_offset); + shstrtab += ".dynamic"; + shstrtab += '\0'; + uint32_t shstrtab_dynsym_offset = shstrtab.size(); + shstrtab += ".dynsym"; + shstrtab += '\0'; + uint32_t shstrtab_dynstr_offset = shstrtab.size(); + shstrtab += ".dynstr"; + shstrtab += '\0'; + uint32_t shstrtab_hash_offset = shstrtab.size(); + shstrtab += ".hash"; + shstrtab += '\0'; + uint32_t shstrtab_rodata_offset = shstrtab.size(); + shstrtab += ".rodata"; + shstrtab += '\0'; + uint32_t shstrtab_text_offset = shstrtab.size(); + shstrtab += ".text"; + shstrtab += '\0'; + uint32_t shstrtab_shstrtab_offset = shstrtab.size(); + shstrtab += ".shstrtab"; + shstrtab += '\0'; + uint32_t shstrtab_size = shstrtab.size(); + expected_offset += shstrtab_size; + if (debug) { + LOG(INFO) << "shstrtab_offset=" << shstrtab_offset << std::hex << " " << shstrtab_offset; + LOG(INFO) << "shstrtab_size=" << shstrtab_size << std::hex << " " << shstrtab_size; + } + + // section headers (after all sections) + uint32_t shdr_alignment = sizeof(llvm::ELF::Elf32_Word); + uint32_t shdr_offset = expected_offset = RoundUp(expected_offset, shdr_alignment); + const uint8_t SH_NULL = 0; + const uint8_t SH_DYNSYM = 1; + const uint8_t SH_DYNSTR = 2; + const uint8_t SH_HASH = 3; + const uint8_t SH_RODATA = 4; + const uint8_t SH_TEXT = 5; + const uint8_t SH_DYNAMIC = 6; + const uint8_t SH_SHSTRTAB = 7; + const uint8_t SH_NUM = 8; + uint32_t shdr_size = sizeof(llvm::ELF::Elf32_Shdr) * SH_NUM; + expected_offset += shdr_size; + if (debug) { + LOG(INFO) << "shdr_offset=" << shdr_offset << std::hex << " " << shdr_offset; + LOG(INFO) << "shdr_size=" << shdr_size << std::hex << " " << shdr_size; + } + + // phase 2: initializing data + + // Elf32_Ehdr + llvm::ELF::Elf32_Ehdr elf_header; + memset(&elf_header, 0, sizeof(elf_header)); + elf_header.e_ident[llvm::ELF::EI_MAG0] = llvm::ELF::ElfMagic[0]; + elf_header.e_ident[llvm::ELF::EI_MAG1] = llvm::ELF::ElfMagic[1]; + elf_header.e_ident[llvm::ELF::EI_MAG2] = llvm::ELF::ElfMagic[2]; + elf_header.e_ident[llvm::ELF::EI_MAG3] = llvm::ELF::ElfMagic[3]; + elf_header.e_ident[llvm::ELF::EI_CLASS] = llvm::ELF::ELFCLASS32; + elf_header.e_ident[llvm::ELF::EI_DATA] = llvm::ELF::ELFDATA2LSB; + elf_header.e_ident[llvm::ELF::EI_VERSION] = llvm::ELF::EV_CURRENT; + elf_header.e_ident[llvm::ELF::EI_OSABI] = llvm::ELF::ELFOSABI_LINUX; + elf_header.e_ident[llvm::ELF::EI_ABIVERSION] = 0; + elf_header.e_type = llvm::ELF::ET_DYN; + switch (compiler_driver_->GetInstructionSet()) { + case kThumb2: { + elf_header.e_machine = llvm::ELF::EM_ARM; + elf_header.e_flags = llvm::ELF::EF_ARM_EABI_VER5; + break; + } + case kX86: { + elf_header.e_machine = llvm::ELF::EM_386; + elf_header.e_flags = 0; + break; + } + case kMips: { + elf_header.e_machine = llvm::ELF::EM_MIPS; + elf_header.e_flags = (llvm::ELF::EF_MIPS_NOREORDER | + llvm::ELF::EF_MIPS_PIC | + llvm::ELF::EF_MIPS_CPIC | + llvm::ELF::EF_MIPS_ABI_O32 | + llvm::ELF::EF_MIPS_ARCH_32R2); + break; + } + case kArm: + default: { + LOG(FATAL) << "Unknown instruction set: " << compiler_driver_->GetInstructionSet(); + break; + } + } + elf_header.e_version = 1; + elf_header.e_entry = 0; + elf_header.e_phoff = phdr_offset; + elf_header.e_shoff = shdr_offset; + elf_header.e_ehsize = sizeof(llvm::ELF::Elf32_Ehdr); + elf_header.e_phentsize = sizeof(llvm::ELF::Elf32_Phdr); + elf_header.e_phnum = PH_NUM; + elf_header.e_shentsize = sizeof(llvm::ELF::Elf32_Shdr); + elf_header.e_shnum = SH_NUM; + elf_header.e_shstrndx = SH_SHSTRTAB; + + // PHDR + llvm::ELF::Elf32_Phdr program_headers[PH_NUM]; + memset(&program_headers, 0, sizeof(program_headers)); + + program_headers[PH_PHDR].p_type = llvm::ELF::PT_PHDR; + program_headers[PH_PHDR].p_offset = phdr_offset; + program_headers[PH_PHDR].p_vaddr = phdr_offset; + program_headers[PH_PHDR].p_paddr = phdr_offset; + program_headers[PH_PHDR].p_filesz = sizeof(program_headers); + program_headers[PH_PHDR].p_memsz = sizeof(program_headers); + program_headers[PH_PHDR].p_flags = llvm::ELF::PF_R; + program_headers[PH_PHDR].p_align = phdr_alignment; + + program_headers[PH_LOAD_R__].p_type = llvm::ELF::PT_LOAD; + program_headers[PH_LOAD_R__].p_offset = 0; + program_headers[PH_LOAD_R__].p_vaddr = 0; + program_headers[PH_LOAD_R__].p_paddr = 0; + program_headers[PH_LOAD_R__].p_filesz = oat_data_offset + oat_data_size; + program_headers[PH_LOAD_R__].p_memsz = oat_data_offset + oat_data_size; + program_headers[PH_LOAD_R__].p_flags = llvm::ELF::PF_R; + program_headers[PH_LOAD_R__].p_align = oat_data_alignment; + + program_headers[PH_LOAD_R_X].p_type = llvm::ELF::PT_LOAD; + program_headers[PH_LOAD_R_X].p_offset = oat_exec_offset; + program_headers[PH_LOAD_R_X].p_vaddr = oat_exec_offset; + program_headers[PH_LOAD_R_X].p_paddr = oat_exec_offset; + program_headers[PH_LOAD_R_X].p_filesz = oat_exec_size; + program_headers[PH_LOAD_R_X].p_memsz = oat_exec_size; + program_headers[PH_LOAD_R_X].p_flags = llvm::ELF::PF_R | llvm::ELF::PF_X; + program_headers[PH_LOAD_R_X].p_align = oat_exec_alignment; + + // TODO: PF_W for DYNAMIC is considered processor specific, do we need it? + program_headers[PH_LOAD_RW_].p_type = llvm::ELF::PT_LOAD; + program_headers[PH_LOAD_RW_].p_offset = dynamic_offset; + program_headers[PH_LOAD_RW_].p_vaddr = dynamic_offset; + program_headers[PH_LOAD_RW_].p_paddr = dynamic_offset; + program_headers[PH_LOAD_RW_].p_filesz = dynamic_size; + program_headers[PH_LOAD_RW_].p_memsz = dynamic_size; + program_headers[PH_LOAD_RW_].p_flags = llvm::ELF::PF_R | llvm::ELF::PF_W; + program_headers[PH_LOAD_RW_].p_align = dynamic_alignment; + + // TODO: PF_W for DYNAMIC is considered processor specific, do we need it? + program_headers[PH_DYNAMIC].p_type = llvm::ELF::PT_DYNAMIC; + program_headers[PH_DYNAMIC].p_offset = dynamic_offset; + program_headers[PH_DYNAMIC].p_vaddr = dynamic_offset; + program_headers[PH_DYNAMIC].p_paddr = dynamic_offset; + program_headers[PH_DYNAMIC].p_filesz = dynamic_size; + program_headers[PH_DYNAMIC].p_memsz = dynamic_size; + program_headers[PH_DYNAMIC].p_flags = llvm::ELF::PF_R | llvm::ELF::PF_W; + program_headers[PH_DYNAMIC].p_align = dynamic_alignment; + + // .dynsym + llvm::ELF::Elf32_Sym dynsym[SYM_NUM]; + memset(&dynsym, 0, sizeof(dynsym)); + + dynsym[SYM_UNDEF].st_name = 0; + dynsym[SYM_UNDEF].st_value = 0; + dynsym[SYM_UNDEF].st_size = 0; + dynsym[SYM_UNDEF].st_info = 0; + dynsym[SYM_UNDEF].st_other = 0; + dynsym[SYM_UNDEF].st_shndx = 0; + + dynsym[SYM_OATDATA].st_name = dynstr_oatdata_offset; + dynsym[SYM_OATDATA].st_value = oat_data_offset; + dynsym[SYM_OATDATA].st_size = oat_data_size; + dynsym[SYM_OATDATA].setBindingAndType(llvm::ELF::STB_GLOBAL, llvm::ELF::STT_OBJECT); + dynsym[SYM_OATDATA].st_other = llvm::ELF::STV_DEFAULT; + dynsym[SYM_OATDATA].st_shndx = SH_RODATA; + + dynsym[SYM_OATEXEC].st_name = dynstr_oatexec_offset; + dynsym[SYM_OATEXEC].st_value = oat_exec_offset; + dynsym[SYM_OATEXEC].st_size = oat_exec_size; + dynsym[SYM_OATEXEC].setBindingAndType(llvm::ELF::STB_GLOBAL, llvm::ELF::STT_OBJECT); + dynsym[SYM_OATEXEC].st_other = llvm::ELF::STV_DEFAULT; + dynsym[SYM_OATEXEC].st_shndx = SH_TEXT; + + dynsym[SYM_OATLASTWORD].st_name = dynstr_oatlastword_offset; + dynsym[SYM_OATLASTWORD].st_value = oat_exec_offset + oat_exec_size - 4; + dynsym[SYM_OATLASTWORD].st_size = 4; + dynsym[SYM_OATLASTWORD].setBindingAndType(llvm::ELF::STB_GLOBAL, llvm::ELF::STT_OBJECT); + dynsym[SYM_OATLASTWORD].st_other = llvm::ELF::STV_DEFAULT; + dynsym[SYM_OATLASTWORD].st_shndx = SH_TEXT; + + // .dynstr initialized above as dynstr + + // .hash + llvm::ELF::Elf32_Word hash[HASH_NUM]; // Note this is Elf32_Word even on 64-bit + hash[HASH_NBUCKET] = 1; + hash[HASH_NCHAIN] = SYM_NUM; + hash[HASH_BUCKET0] = SYM_OATDATA; + hash[HASH_BUCKET0 + 1 + SYM_UNDEF] = SYM_UNDEF; + hash[HASH_BUCKET0 + 1 + SYM_OATDATA] = SYM_OATEXEC; + hash[HASH_BUCKET0 + 1 + SYM_OATEXEC] = SYM_OATLASTWORD; + hash[HASH_BUCKET0 + 1 + SYM_OATLASTWORD] = SYM_UNDEF; + + // .rodata and .text content come from oat_contents + + // .dynamic + llvm::ELF::Elf32_Dyn dynamic_headers[DH_NUM]; + memset(&dynamic_headers, 0, sizeof(dynamic_headers)); + + dynamic_headers[DH_SONAME].d_tag = llvm::ELF::DT_SONAME; + dynamic_headers[DH_SONAME].d_un.d_val = dynstr_soname_offset; + + dynamic_headers[DH_HASH].d_tag = llvm::ELF::DT_HASH; + dynamic_headers[DH_HASH].d_un.d_ptr = hash_offset; + + dynamic_headers[DH_SYMTAB].d_tag = llvm::ELF::DT_SYMTAB; + dynamic_headers[DH_SYMTAB].d_un.d_ptr = dynsym_offset; + + dynamic_headers[DH_SYMENT].d_tag = llvm::ELF::DT_SYMENT; + dynamic_headers[DH_SYMENT].d_un.d_val = sizeof(llvm::ELF::Elf32_Sym); + + dynamic_headers[DH_STRTAB].d_tag = llvm::ELF::DT_STRTAB; + dynamic_headers[DH_STRTAB].d_un.d_ptr = dynstr_offset; + + dynamic_headers[DH_STRSZ].d_tag = llvm::ELF::DT_STRSZ; + dynamic_headers[DH_STRSZ].d_un.d_val = dynstr_size; + + dynamic_headers[DH_NULL].d_tag = llvm::ELF::DT_NULL; + dynamic_headers[DH_NULL].d_un.d_val = 0; + + // .shstrtab initialized above as shstrtab + + // section headers (after all sections) + llvm::ELF::Elf32_Shdr section_headers[SH_NUM]; + memset(§ion_headers, 0, sizeof(section_headers)); + + section_headers[SH_NULL].sh_name = 0; + section_headers[SH_NULL].sh_type = llvm::ELF::SHT_NULL; + section_headers[SH_NULL].sh_flags = 0; + section_headers[SH_NULL].sh_addr = 0; + section_headers[SH_NULL].sh_offset = 0; + section_headers[SH_NULL].sh_size = 0; + section_headers[SH_NULL].sh_link = 0; + section_headers[SH_NULL].sh_info = 0; + section_headers[SH_NULL].sh_addralign = 0; + section_headers[SH_NULL].sh_entsize = 0; + + section_headers[SH_DYNSYM].sh_name = shstrtab_dynsym_offset; + section_headers[SH_DYNSYM].sh_type = llvm::ELF::SHT_DYNSYM; + section_headers[SH_DYNSYM].sh_flags = llvm::ELF::SHF_ALLOC; + section_headers[SH_DYNSYM].sh_addr = dynsym_offset; + section_headers[SH_DYNSYM].sh_offset = dynsym_offset; + section_headers[SH_DYNSYM].sh_size = dynsym_size; + section_headers[SH_DYNSYM].sh_link = SH_DYNSTR; + section_headers[SH_DYNSYM].sh_info = 1; // 1 because we have not STB_LOCAL symbols + section_headers[SH_DYNSYM].sh_addralign = dynsym_alignment; + section_headers[SH_DYNSYM].sh_entsize = sizeof(llvm::ELF::Elf32_Sym); + + section_headers[SH_DYNSTR].sh_name = shstrtab_dynstr_offset; + section_headers[SH_DYNSTR].sh_type = llvm::ELF::SHT_STRTAB; + section_headers[SH_DYNSTR].sh_flags = llvm::ELF::SHF_ALLOC; + section_headers[SH_DYNSTR].sh_addr = dynstr_offset; + section_headers[SH_DYNSTR].sh_offset = dynstr_offset; + section_headers[SH_DYNSTR].sh_size = dynstr_size; + section_headers[SH_DYNSTR].sh_link = 0; + section_headers[SH_DYNSTR].sh_info = 0; + section_headers[SH_DYNSTR].sh_addralign = dynstr_alignment; + section_headers[SH_DYNSTR].sh_entsize = 0; + + section_headers[SH_HASH].sh_name = shstrtab_hash_offset; + section_headers[SH_HASH].sh_type = llvm::ELF::SHT_HASH; + section_headers[SH_HASH].sh_flags = llvm::ELF::SHF_ALLOC; + section_headers[SH_HASH].sh_addr = hash_offset; + section_headers[SH_HASH].sh_offset = hash_offset; + section_headers[SH_HASH].sh_size = hash_size; + section_headers[SH_HASH].sh_link = SH_DYNSYM; + section_headers[SH_HASH].sh_info = 0; + section_headers[SH_HASH].sh_addralign = hash_alignment; + section_headers[SH_HASH].sh_entsize = sizeof(llvm::ELF::Elf32_Word); // This is Elf32_Word even on 64-bit + + section_headers[SH_RODATA].sh_name = shstrtab_rodata_offset; + section_headers[SH_RODATA].sh_type = llvm::ELF::SHT_PROGBITS; + section_headers[SH_RODATA].sh_flags = llvm::ELF::SHF_ALLOC; + section_headers[SH_RODATA].sh_addr = oat_data_offset; + section_headers[SH_RODATA].sh_offset = oat_data_offset; + section_headers[SH_RODATA].sh_size = oat_data_size; + section_headers[SH_RODATA].sh_link = 0; + section_headers[SH_RODATA].sh_info = 0; + section_headers[SH_RODATA].sh_addralign = oat_data_alignment; + section_headers[SH_RODATA].sh_entsize = 0; + + section_headers[SH_TEXT].sh_name = shstrtab_text_offset; + section_headers[SH_TEXT].sh_type = llvm::ELF::SHT_PROGBITS; + section_headers[SH_TEXT].sh_flags = llvm::ELF::SHF_ALLOC | llvm::ELF::SHF_EXECINSTR; + section_headers[SH_TEXT].sh_addr = oat_exec_offset; + section_headers[SH_TEXT].sh_offset = oat_exec_offset; + section_headers[SH_TEXT].sh_size = oat_exec_size; + section_headers[SH_TEXT].sh_link = 0; + section_headers[SH_TEXT].sh_info = 0; + section_headers[SH_TEXT].sh_addralign = oat_exec_alignment; + section_headers[SH_TEXT].sh_entsize = 0; + + // TODO: SHF_WRITE for .dynamic is considered processor specific, do we need it? + section_headers[SH_DYNAMIC].sh_name = shstrtab_dynamic_offset; + section_headers[SH_DYNAMIC].sh_type = llvm::ELF::SHT_DYNAMIC; + section_headers[SH_DYNAMIC].sh_flags = llvm::ELF::SHF_WRITE | llvm::ELF::SHF_ALLOC; + section_headers[SH_DYNAMIC].sh_addr = dynamic_offset; + section_headers[SH_DYNAMIC].sh_offset = dynamic_offset; + section_headers[SH_DYNAMIC].sh_size = dynamic_size; + section_headers[SH_DYNAMIC].sh_link = SH_DYNSTR; + section_headers[SH_DYNAMIC].sh_info = 0; + section_headers[SH_DYNAMIC].sh_addralign = dynamic_alignment; + section_headers[SH_DYNAMIC].sh_entsize = sizeof(llvm::ELF::Elf32_Dyn); + + section_headers[SH_SHSTRTAB].sh_name = shstrtab_shstrtab_offset; + section_headers[SH_SHSTRTAB].sh_type = llvm::ELF::SHT_STRTAB; + section_headers[SH_SHSTRTAB].sh_flags = 0; + section_headers[SH_SHSTRTAB].sh_addr = shstrtab_offset; + section_headers[SH_SHSTRTAB].sh_offset = shstrtab_offset; + section_headers[SH_SHSTRTAB].sh_size = shstrtab_size; + section_headers[SH_SHSTRTAB].sh_link = 0; + section_headers[SH_SHSTRTAB].sh_info = 0; + section_headers[SH_SHSTRTAB].sh_addralign = shstrtab_alignment; + section_headers[SH_SHSTRTAB].sh_entsize = 0; + + // phase 3: writing file + + // Elf32_Ehdr + if (!elf_file_->WriteFully(&elf_header, sizeof(elf_header))) { + PLOG(ERROR) << "Failed to write ELF header for " << elf_file_->GetPath(); + return false; + } + + // PHDR + if (static_cast<off_t>(phdr_offset) != lseek(elf_file_->Fd(), 0, SEEK_CUR)) { + PLOG(ERROR) << "Failed to be at expected ELF program header offset phdr_offset " + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(program_headers, sizeof(program_headers))) { + PLOG(ERROR) << "Failed to write ELF program headers for " << elf_file_->GetPath(); + return false; + } + + // .dynsym + DCHECK_LE(phdr_offset + phdr_size, dynsym_offset); + if (static_cast<off_t>(dynsym_offset) != lseek(elf_file_->Fd(), dynsym_offset, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to .dynsym offset location " << dynsym_offset + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(dynsym, sizeof(dynsym))) { + PLOG(ERROR) << "Failed to write .dynsym for " << elf_file_->GetPath(); + return false; + } + + // .dynstr + DCHECK_LE(dynsym_offset + dynsym_size, dynstr_offset); + if (static_cast<off_t>(dynstr_offset) != lseek(elf_file_->Fd(), dynstr_offset, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to .dynstr offset " << dynstr_offset + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(&dynstr[0], dynsym_size)) { + PLOG(ERROR) << "Failed to write .dynsym for " << elf_file_->GetPath(); + return false; + } + + // .hash + DCHECK_LE(dynstr_offset + dynstr_size, hash_offset); + if (static_cast<off_t>(hash_offset) != lseek(elf_file_->Fd(), hash_offset, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to .hash offset " << hash_offset + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(hash, sizeof(hash))) { + PLOG(ERROR) << "Failed to write .dynsym for " << elf_file_->GetPath(); + return false; + } + + // .rodata .text + DCHECK_LE(hash_offset + hash_size, oat_data_offset); + if (static_cast<off_t>(oat_data_offset) != lseek(elf_file_->Fd(), oat_data_offset, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to .rodata offset " << oat_data_offset + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(&oat_contents[0], oat_contents.size())) { + PLOG(ERROR) << "Failed to write .rodata and .text for " << elf_file_->GetPath(); + return false; + } + + // .dynamic + DCHECK_LE(oat_data_offset + oat_contents.size(), dynamic_offset); + if (static_cast<off_t>(dynamic_offset) != lseek(elf_file_->Fd(), dynamic_offset, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to .dynamic offset " << dynamic_offset + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(&dynamic_headers[0], dynamic_size)) { + PLOG(ERROR) << "Failed to write .dynamic for " << elf_file_->GetPath(); + return false; + } + + // .shstrtab + DCHECK_LE(dynamic_offset + dynamic_size, shstrtab_offset); + if (static_cast<off_t>(shstrtab_offset) != lseek(elf_file_->Fd(), shstrtab_offset, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to .shstrtab offset " << shstrtab_offset + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(&shstrtab[0], shstrtab_size)) { + PLOG(ERROR) << "Failed to write .shstrtab for " << elf_file_->GetPath(); + return false; + } + + // section headers (after all sections) + DCHECK_LE(shstrtab_offset + shstrtab_size, shdr_offset); + if (static_cast<off_t>(shdr_offset) != lseek(elf_file_->Fd(), shdr_offset, SEEK_SET)) { + PLOG(ERROR) << "Failed to seek to ELF section headers offset " << shdr_offset + << " for " << elf_file_->GetPath(); + return false; + } + if (!elf_file_->WriteFully(section_headers, sizeof(section_headers))) { + PLOG(ERROR) << "Failed to write ELF section headers for " << elf_file_->GetPath(); + return false; + } + + LOG(INFO) << "ELF file written successfully: " << elf_file_->GetPath(); + return true; +} + +} // namespace art |