209 lines · cpp
1//===-- sanitizer_symbolizer_mac.cpp --------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file is shared between various sanitizers' runtime libraries.10//11// Implementation of Mac-specific "atos" symbolizer.12//===----------------------------------------------------------------------===//13 14#include "sanitizer_platform.h"15#if SANITIZER_APPLE16 17# include <dlfcn.h>18# include <errno.h>19# include <stdlib.h>20# include <sys/wait.h>21# include <unistd.h>22# include <util.h>23 24# include "sanitizer_allocator_internal.h"25# include "sanitizer_mac.h"26# include "sanitizer_symbolizer_mac.h"27 28namespace __sanitizer {29 30bool DlAddrSymbolizer::SymbolizePC(uptr addr, SymbolizedStack *stack) {31 Dl_info info;32 int result = dladdr((const void *)addr, &info);33 if (!result || !info.dli_sname) return false;34 35 // Compute offset if possible. `dladdr()` doesn't always ensure that `addr >=36 // sym_addr` so only compute the offset when this holds. Failure to find the37 // function offset is not treated as a failure because it might still be38 // possible to get the symbol name.39 uptr sym_addr = reinterpret_cast<uptr>(info.dli_saddr);40 if (addr >= sym_addr) {41 stack->info.function_offset = addr - sym_addr;42 }43 44 const char *demangled = DemangleSwiftAndCXX(info.dli_sname);45 if (!demangled)46 demangled = info.dli_sname;47 stack->info.function = internal_strdup(demangled);48 return true;49}50 51bool DlAddrSymbolizer::SymbolizeData(uptr addr, DataInfo *datainfo) {52 Dl_info info;53 int result = dladdr((const void *)addr, &info);54 if (!result || !info.dli_sname) return false;55 const char *demangled = DemangleSwiftAndCXX(info.dli_sname);56 if (!demangled)57 demangled = info.dli_sname;58 datainfo->name = internal_strdup(demangled);59 datainfo->start = (uptr)info.dli_saddr;60 return true;61}62 63class AtosSymbolizerProcess final : public SymbolizerProcess {64 public:65 explicit AtosSymbolizerProcess(const char *path)66 : SymbolizerProcess(path, /*use_posix_spawn*/ true) {67 pid_str_[0] = '\0';68 }69 70 private:71 bool StartSymbolizerSubprocess() override {72 // Put the string command line argument in the object so that it outlives73 // the call to GetArgV.74 internal_snprintf(pid_str_, sizeof(pid_str_), "%d", (int)internal_getpid());75 76 // Configure sandbox before starting atos process.77 return SymbolizerProcess::StartSymbolizerSubprocess();78 }79 80 bool ReachedEndOfOutput(const char *buffer, uptr length) const override {81 return (length >= 1 && buffer[length - 1] == '\n');82 }83 84 void GetArgV(const char *path_to_binary,85 const char *(&argv)[kArgVMax]) const override {86 int i = 0;87 argv[i++] = path_to_binary;88 argv[i++] = "-p";89 argv[i++] = &pid_str_[0];90 if (GetMacosAlignedVersion() == MacosVersion(10, 9)) {91 // On Mavericks atos prints a deprecation warning which we suppress by92 // passing -d. The warning isn't present on other OSX versions, even the93 // newer ones.94 argv[i++] = "-d";95 }96 argv[i++] = nullptr;97 CHECK_LE(i, kArgVMax);98 }99 100 char pid_str_[16];101};102 103#undef K_ATOS_ENV_VAR104 105static bool ParseCommandOutput(const char *str, uptr addr, char **out_name,106 char **out_module, char **out_file, uptr *line,107 uptr *start_address) {108 // Trim ending newlines.109 char *trim;110 ExtractTokenUpToDelimiter(str, "\n", &trim);111 112 // The line from `atos` is in one of these formats:113 // myfunction (in library.dylib) (sourcefile.c:17)114 // myfunction (in library.dylib) + 0x1fe115 // myfunction (in library.dylib) + 15116 // 0xdeadbeef (in library.dylib) + 0x1fe117 // 0xdeadbeef (in library.dylib) + 15118 // 0xdeadbeef (in library.dylib)119 // 0xdeadbeef120 121 const char *rest = trim;122 char *symbol_name;123 rest = ExtractTokenUpToDelimiter(rest, " (in ", &symbol_name);124 if (rest[0] == '\0') {125 InternalFree(symbol_name);126 InternalFree(trim);127 return false;128 }129 130 if (internal_strncmp(symbol_name, "0x", 2) != 0)131 *out_name = symbol_name;132 else133 InternalFree(symbol_name);134 rest = ExtractTokenUpToDelimiter(rest, ") ", out_module);135 136 if (rest[0] == '(') {137 if (out_file) {138 rest++;139 rest = ExtractTokenUpToDelimiter(rest, ":", out_file);140 char *extracted_line_number;141 rest = ExtractTokenUpToDelimiter(rest, ")", &extracted_line_number);142 if (line) *line = (uptr)internal_atoll(extracted_line_number);143 InternalFree(extracted_line_number);144 }145 } else if (rest[0] == '+') {146 rest += 2;147 uptr offset = internal_atoll(rest);148 if (start_address) *start_address = addr - offset;149 }150 151 InternalFree(trim);152 return true;153}154 155AtosSymbolizer::AtosSymbolizer(const char *path, LowLevelAllocator *allocator)156 : process_(new (*allocator) AtosSymbolizerProcess(path)) {}157 158bool AtosSymbolizer::SymbolizePC(uptr addr, SymbolizedStack *stack) {159 if (!process_) return false;160 if (addr == 0) return false;161 char command[32];162 internal_snprintf(command, sizeof(command), "0x%zx\n", addr);163 const char *buf = process_->SendCommand(command);164 if (!buf) return false;165 uptr line;166 uptr start_address = AddressInfo::kUnknown;167 if (!ParseCommandOutput(buf, addr, &stack->info.function, &stack->info.module,168 &stack->info.file, &line, &start_address)) {169 Report("WARNING: atos failed to symbolize address \"0x%zx\"\n", addr);170 return false;171 }172 stack->info.line = (int)line;173 174 if (start_address == AddressInfo::kUnknown) {175 // Fallback to dladdr() to get function start address if atos doesn't report176 // it.177 Dl_info info;178 int result = dladdr((const void *)addr, &info);179 if (result)180 start_address = reinterpret_cast<uptr>(info.dli_saddr);181 }182 183 // Only assign to `function_offset` if we were able to get the function's184 // start address and we got a sensible `start_address` (dladdr doesn't always185 // ensure that `addr >= sym_addr`).186 if (start_address != AddressInfo::kUnknown && addr >= start_address) {187 stack->info.function_offset = addr - start_address;188 }189 return true;190}191 192bool AtosSymbolizer::SymbolizeData(uptr addr, DataInfo *info) {193 if (!process_) return false;194 char command[32];195 internal_snprintf(command, sizeof(command), "0x%zx\n", addr);196 const char *buf = process_->SendCommand(command);197 if (!buf) return false;198 if (!ParseCommandOutput(buf, addr, &info->name, &info->module, nullptr,199 nullptr, &info->start)) {200 process_ = nullptr;201 return false;202 }203 return true;204}205 206} // namespace __sanitizer207 208#endif // SANITIZER_APPLE209