1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef SIMPLE_PERF_READ_ELF_H_ 18 #define SIMPLE_PERF_READ_ELF_H_ 19 20 #include <functional> 21 #include <ostream> 22 #include <string> 23 #include "build_id.h" 24 25 // Read ELF functions are called in different situations, so it is hard to 26 // decide whether to report error or not. So read ELF functions don't report 27 // error when something wrong happens, instead they return ElfStatus, which 28 // identifies different errors met while reading elf file. 29 enum ElfStatus { 30 NO_ERROR, 31 FILE_NOT_FOUND, 32 READ_FAILED, 33 FILE_MALFORMED, 34 NO_SYMBOL_TABLE, 35 NO_BUILD_ID, 36 BUILD_ID_MISMATCH, 37 SECTION_NOT_FOUND, 38 }; 39 40 std::ostream& operator<<(std::ostream& os, const ElfStatus& status); 41 42 ElfStatus GetBuildIdFromNoteFile(const std::string& filename, BuildId* build_id); 43 ElfStatus GetBuildIdFromElfFile(const std::string& filename, BuildId* build_id); 44 ElfStatus GetBuildIdFromEmbeddedElfFile(const std::string& filename, uint64_t file_offset, 45 uint32_t file_size, BuildId* build_id); 46 47 // The symbol prefix used to indicate that the symbol belongs to android linker. 48 static const std::string linker_prefix = "__dl_"; 49 50 struct ElfFileSymbol { 51 uint64_t vaddr; 52 uint64_t len; 53 bool is_func; 54 bool is_label; 55 bool is_in_text_section; 56 std::string name; 57 ElfFileSymbolElfFileSymbol58 ElfFileSymbol() : vaddr(0), len(0), is_func(false), is_label(false), is_in_text_section(false) { 59 } 60 }; 61 62 ElfStatus ParseSymbolsFromElfFile(const std::string& filename, 63 const BuildId& expected_build_id, 64 const std::function<void(const ElfFileSymbol&)>& callback); 65 ElfStatus ParseSymbolsFromEmbeddedElfFile(const std::string& filename, uint64_t file_offset, 66 uint32_t file_size, const BuildId& expected_build_id, 67 const std::function<void(const ElfFileSymbol&)>& callback); 68 ElfStatus ParseSymbolsFromElfFileInMemory(const char* data, size_t size, 69 const std::function<void(const ElfFileSymbol&)>& callback); 70 ElfStatus ParseDynamicSymbolsFromElfFile(const std::string& filename, 71 const std::function<void(const ElfFileSymbol&)>& callback); 72 73 ElfStatus ReadMinExecutableVirtualAddressFromElfFile(const std::string& filename, 74 const BuildId& expected_build_id, 75 uint64_t* min_addr, 76 uint64_t* file_offset_of_min_vaddr); 77 ElfStatus ReadMinExecutableVirtualAddressFromEmbeddedElfFile(const std::string& filename, 78 uint64_t file_offset, 79 uint32_t file_size, 80 const BuildId& expected_build_id, 81 uint64_t* min_vaddr, 82 uint64_t* file_offset_of_min_vaddr); 83 84 ElfStatus ReadSectionFromElfFile(const std::string& filename, const std::string& section_name, 85 std::string* content); 86 87 // Expose the following functions for unit tests. 88 bool IsArmMappingSymbol(const char* name); 89 ElfStatus IsValidElfFile(int fd); 90 bool IsValidElfFileMagic(const char* buf, size_t buf_size); 91 ElfStatus IsValidElfPath(const std::string& filename); 92 bool GetBuildIdFromNoteSection(const char* section, size_t section_size, BuildId* build_id); 93 94 #endif // SIMPLE_PERF_READ_ELF_H_ 95