| /* |
| * 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. |
| */ |
| |
| #ifndef ART_SRC_ELF_FILE_H_ |
| #define ART_SRC_ELF_FILE_H_ |
| |
| #include <map> |
| #include <vector> |
| |
| #include <llvm/Support/ELF.h> |
| |
| #include "base/unix_file/fd_file.h" |
| #include "globals.h" |
| #include "mem_map.h" |
| #include "os.h" |
| #include "UniquePtr.h" |
| |
| namespace art { |
| |
| // Used for compile time and runtime for ElfFile access. Because of |
| // the need for use at runtime, cannot directly use LLVM classes such as |
| // ELFObjectFile. |
| class ElfFile { |
| public: |
| static ElfFile* Open(File* file, bool writable, bool program_header_only); |
| ~ElfFile(); |
| |
| // Load segments into memory based on PT_LOAD program headers |
| |
| File& GetFile() const { |
| return *file_; |
| } |
| |
| byte* Begin() { |
| return map_->Begin(); |
| } |
| |
| byte* End() { |
| return map_->End(); |
| } |
| |
| size_t Size() const { |
| return map_->Size(); |
| } |
| |
| ::llvm::ELF::Elf32_Ehdr& GetHeader(); |
| |
| ::llvm::ELF::Elf32_Word GetProgramHeaderNum(); |
| ::llvm::ELF::Elf32_Phdr& GetProgramHeader(::llvm::ELF::Elf32_Word); |
| ::llvm::ELF::Elf32_Phdr* FindProgamHeaderByType(::llvm::ELF::Elf32_Word type); |
| |
| ::llvm::ELF::Elf32_Word GetSectionHeaderNum(); |
| ::llvm::ELF::Elf32_Shdr& GetSectionHeader(::llvm::ELF::Elf32_Word); |
| ::llvm::ELF::Elf32_Shdr* FindSectionByType(::llvm::ELF::Elf32_Word type); |
| |
| ::llvm::ELF::Elf32_Shdr& GetSectionNameStringSection(); |
| |
| // Find .dynsym using .hash for more efficient lookup than FindSymbolAddress. |
| byte* FindDynamicSymbolAddress(const std::string& symbol_name); |
| |
| static bool IsSymbolSectionType(::llvm::ELF::Elf32_Word section_type); |
| ::llvm::ELF::Elf32_Word GetSymbolNum(::llvm::ELF::Elf32_Shdr&); |
| ::llvm::ELF::Elf32_Sym& GetSymbol(::llvm::ELF::Elf32_Word section_type, ::llvm::ELF::Elf32_Word i); |
| |
| // Find symbol in specified table, returning NULL if it is not found. |
| // |
| // If build_map is true, builds a map to speed repeated access. The |
| // map does not included untyped symbol values (aka STT_NOTYPE) |
| // since they can contain duplicates. If build_map is false, the map |
| // will be used if it was already created. Typically build_map |
| // should be set unless only a small number of symbols will be |
| // looked up. |
| ::llvm::ELF::Elf32_Sym* FindSymbolByName(::llvm::ELF::Elf32_Word section_type, |
| const std::string& symbol_name, |
| bool build_map); |
| |
| // Find address of symbol in specified table, returning 0 if it is |
| // not found. See FindSymbolByName for an explanation of build_map. |
| ::llvm::ELF::Elf32_Addr FindSymbolAddress(::llvm::ELF::Elf32_Word section_type, |
| const std::string& symbol_name, |
| bool build_map); |
| |
| // Lookup a string given string section and offset. Returns NULL for |
| // special 0 offset. |
| const char* GetString(::llvm::ELF::Elf32_Shdr&, ::llvm::ELF::Elf32_Word); |
| |
| // Lookup a string by section type. Returns NULL for special 0 offset. |
| const char* GetString(::llvm::ELF::Elf32_Word section_type, ::llvm::ELF::Elf32_Word); |
| |
| ::llvm::ELF::Elf32_Word GetDynamicNum(); |
| ::llvm::ELF::Elf32_Dyn& GetDynamic(::llvm::ELF::Elf32_Word); |
| ::llvm::ELF::Elf32_Word FindDynamicValueByType(::llvm::ELF::Elf32_Sword type); |
| |
| ::llvm::ELF::Elf32_Word GetRelNum(::llvm::ELF::Elf32_Shdr&); |
| ::llvm::ELF::Elf32_Rel& GetRel(::llvm::ELF::Elf32_Shdr&, ::llvm::ELF::Elf32_Word); |
| |
| ::llvm::ELF::Elf32_Word GetRelaNum(::llvm::ELF::Elf32_Shdr&); |
| ::llvm::ELF::Elf32_Rela& GetRela(::llvm::ELF::Elf32_Shdr&, ::llvm::ELF::Elf32_Word); |
| |
| // Returns the expected size when the file is loaded at runtime |
| size_t GetLoadedSize(); |
| |
| // Load segments into memory based on PT_LOAD program headers |
| bool Load(); |
| |
| private: |
| ElfFile(); |
| |
| bool Setup(File* file, bool writable, bool program_header_only); |
| |
| bool SetMap(MemMap* map); |
| |
| byte* GetProgramHeadersStart(); |
| byte* GetSectionHeadersStart(); |
| ::llvm::ELF::Elf32_Phdr& GetDynamicProgramHeader(); |
| ::llvm::ELF::Elf32_Dyn* GetDynamicSectionStart(); |
| ::llvm::ELF::Elf32_Sym* GetSymbolSectionStart(::llvm::ELF::Elf32_Word section_type); |
| const char* GetStringSectionStart(::llvm::ELF::Elf32_Word section_type); |
| ::llvm::ELF::Elf32_Rel* GetRelSectionStart(::llvm::ELF::Elf32_Shdr&); |
| ::llvm::ELF::Elf32_Rela* GetRelaSectionStart(::llvm::ELF::Elf32_Shdr&); |
| ::llvm::ELF::Elf32_Word* GetHashSectionStart(); |
| ::llvm::ELF::Elf32_Word GetHashBucketNum(); |
| ::llvm::ELF::Elf32_Word GetHashChainNum(); |
| ::llvm::ELF::Elf32_Word GetHashBucket(size_t i); |
| ::llvm::ELF::Elf32_Word GetHashChain(size_t i); |
| |
| typedef std::map<std::string, ::llvm::ELF::Elf32_Sym*> SymbolTable; |
| SymbolTable** GetSymbolTable(::llvm::ELF::Elf32_Word section_type); |
| |
| File* file_; |
| bool writable_; |
| bool program_header_only_; |
| |
| // ELF header mapping. If program_header_only_ is false, will actually point to the entire elf file. |
| UniquePtr<MemMap> map_; |
| ::llvm::ELF::Elf32_Ehdr* header_; |
| std::vector<MemMap*> segments_; |
| |
| // Pointer to start of first PT_LOAD program segment after Load() when program_header_only_ is true. |
| byte* base_address_; |
| |
| // The program header should always available but use GetProgramHeadersStart() to be sure. |
| byte* program_headers_start_; |
| |
| // Conditionally available values. Use accessors to ensure they exist if they are required. |
| byte* section_headers_start_; |
| ::llvm::ELF::Elf32_Phdr* dynamic_program_header_; |
| ::llvm::ELF::Elf32_Dyn* dynamic_section_start_; |
| ::llvm::ELF::Elf32_Sym* symtab_section_start_; |
| ::llvm::ELF::Elf32_Sym* dynsym_section_start_; |
| const char* strtab_section_start_; |
| const char* dynstr_section_start_; |
| ::llvm::ELF::Elf32_Word* hash_section_start_; |
| |
| SymbolTable* symtab_symbol_table_; |
| SymbolTable* dynsym_symbol_table_; |
| }; |
| |
| } // namespace art |
| |
| #endif // ART_SRC_ELF_FILE_H_ |