symbolize.h (5322B)
1 // Copyright 2018 The Abseil Authors. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // https://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 // This file contains internal parts of the Abseil symbolizer. 16 // Do not depend on the anything in this file, it may change at anytime. 17 18 #ifndef ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_ 19 #define ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_ 20 21 #ifdef __cplusplus 22 23 #include <cstddef> 24 #include <cstdint> 25 26 #include "absl/base/config.h" 27 #include "absl/strings/string_view.h" 28 29 #ifdef ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE 30 #error ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE cannot be directly set 31 #elif defined(__ELF__) && defined(__GLIBC__) && !defined(__native_client__) \ 32 && !defined(__asmjs__) && !defined(__wasm__) 33 #define ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE 1 34 35 #include <elf.h> 36 #include <link.h> // For ElfW() macro. 37 #include <functional> 38 #include <string> 39 40 namespace absl { 41 ABSL_NAMESPACE_BEGIN 42 namespace debugging_internal { 43 44 // Iterates over all sections, invoking callback on each with the section name 45 // and the section header. 46 // 47 // Returns true on success; otherwise returns false in case of errors. 48 // 49 // This is not async-signal-safe. 50 bool ForEachSection(int fd, 51 const std::function<bool(absl::string_view name, 52 const ElfW(Shdr) &)>& callback); 53 54 // Gets the section header for the given name, if it exists. Returns true on 55 // success. Otherwise, returns false. 56 bool GetSectionHeaderByName(int fd, const char *name, size_t name_len, 57 ElfW(Shdr) *out); 58 59 } // namespace debugging_internal 60 ABSL_NAMESPACE_END 61 } // namespace absl 62 63 #endif // ABSL_INTERNAL_HAVE_ELF_SYMBOLIZE 64 65 #ifdef ABSL_INTERNAL_HAVE_DARWIN_SYMBOLIZE 66 #error ABSL_INTERNAL_HAVE_DARWIN_SYMBOLIZE cannot be directly set 67 #elif defined(__APPLE__) 68 #define ABSL_INTERNAL_HAVE_DARWIN_SYMBOLIZE 1 69 #endif 70 71 #ifdef ABSL_INTERNAL_HAVE_EMSCRIPTEN_SYMBOLIZE 72 #error ABSL_INTERNAL_HAVE_EMSCRIPTEN_SYMBOLIZE cannot be directly set 73 #elif defined(__EMSCRIPTEN__) 74 #define ABSL_INTERNAL_HAVE_EMSCRIPTEN_SYMBOLIZE 1 75 #endif 76 77 namespace absl { 78 ABSL_NAMESPACE_BEGIN 79 namespace debugging_internal { 80 81 struct SymbolDecoratorArgs { 82 // The program counter we are getting symbolic name for. 83 const void *pc; 84 // 0 for main executable, load address for shared libraries. 85 ptrdiff_t relocation; 86 // Read-only file descriptor for ELF image covering "pc", 87 // or -1 if no such ELF image exists in /proc/self/maps. 88 int fd; 89 // Output buffer, size. 90 // Note: the buffer may not be empty -- default symbolizer may have already 91 // produced some output, and earlier decorators may have adorned it in 92 // some way. You are free to replace or augment the contents (within the 93 // symbol_buf_size limit). 94 char *const symbol_buf; 95 size_t symbol_buf_size; 96 // Temporary scratch space, size. 97 // Use that space in preference to allocating your own stack buffer to 98 // conserve stack. 99 char *const tmp_buf; 100 size_t tmp_buf_size; 101 // User-provided argument 102 void* arg; 103 }; 104 using SymbolDecorator = void (*)(const SymbolDecoratorArgs *); 105 106 // Installs a function-pointer as a decorator. Returns a value less than zero 107 // if the system cannot install the decorator. Otherwise, returns a unique 108 // identifier corresponding to the decorator. This identifier can be used to 109 // uninstall the decorator - See RemoveSymbolDecorator() below. 110 int InstallSymbolDecorator(SymbolDecorator decorator, void* arg); 111 112 // Removes a previously installed function-pointer decorator. Parameter "ticket" 113 // is the return-value from calling InstallSymbolDecorator(). 114 bool RemoveSymbolDecorator(int ticket); 115 116 // Remove all installed decorators. Returns true if successful, false if 117 // symbolization is currently in progress. 118 bool RemoveAllSymbolDecorators(); 119 120 // Registers an address range to a file mapping. 121 // 122 // Preconditions: 123 // start <= end 124 // filename != nullptr 125 // 126 // Returns true if the file was successfully registered. 127 bool RegisterFileMappingHint(const void* start, const void* end, 128 uint64_t offset, const char* filename); 129 130 // Looks up the file mapping registered by RegisterFileMappingHint for an 131 // address range. If there is one, the file name is stored in *filename and 132 // *start and *end are modified to reflect the registered mapping. Returns 133 // whether any hint was found. 134 bool GetFileMappingHint(const void** start, const void** end, uint64_t* offset, 135 const char** filename); 136 137 } // namespace debugging_internal 138 ABSL_NAMESPACE_END 139 } // namespace absl 140 141 #endif // __cplusplus 142 143 #include <stdbool.h> 144 145 #ifdef __cplusplus 146 extern "C" 147 #endif // __cplusplus 148 149 bool 150 AbslInternalGetFileMappingHint(const void** start, const void** end, 151 uint64_t* offset, const char** filename); 152 153 #endif // ABSL_DEBUGGING_INTERNAL_SYMBOLIZE_H_