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symbolize_darwin.inc (3293B)


      1 // Copyright 2020 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 #include <cxxabi.h>
     16 #include <execinfo.h>
     17 
     18 #include <algorithm>
     19 #include <cstring>
     20 
     21 #include "absl/base/internal/raw_logging.h"
     22 #include "absl/debugging/internal/demangle.h"
     23 #include "absl/strings/numbers.h"
     24 #include "absl/strings/str_cat.h"
     25 #include "absl/strings/string_view.h"
     26 
     27 namespace absl {
     28 ABSL_NAMESPACE_BEGIN
     29 
     30 void InitializeSymbolizer(const char*) {}
     31 
     32 namespace debugging_internal {
     33 namespace {
     34 
     35 static std::string GetSymbolString(absl::string_view backtrace_line) {
     36  // Example Backtrace lines:
     37  // 0   libimaging_shared.dylib             0x018c152a
     38  // _ZNSt11_Deque_baseIN3nik7mediadb4PageESaIS2_EE17_M_initialize_mapEm + 3478
     39  //
     40  // or
     41  // 0   libimaging_shared.dylib             0x0000000001895c39
     42  // _ZN3nik4util19register_shared_ptrINS_3gpu7TextureEEEvPKvS5_ + 39
     43  //
     44  // or
     45  // 0   mysterious_app                      0x0124000120120009 main + 17
     46  auto address_pos = backtrace_line.find(" 0x");
     47  if (address_pos == absl::string_view::npos) return std::string();
     48  absl::string_view symbol_view = backtrace_line.substr(address_pos + 1);
     49 
     50  auto space_pos = symbol_view.find(" ");
     51  if (space_pos == absl::string_view::npos) return std::string();
     52  symbol_view = symbol_view.substr(space_pos + 1);  // to mangled symbol
     53 
     54  auto plus_pos = symbol_view.find(" + ");
     55  if (plus_pos == absl::string_view::npos) return std::string();
     56  symbol_view = symbol_view.substr(0, plus_pos);  // strip remainng
     57 
     58  return std::string(symbol_view);
     59 }
     60 
     61 }  // namespace
     62 }  // namespace debugging_internal
     63 
     64 bool Symbolize(const void* pc, char* out, int out_size) {
     65  if (out_size <= 0 || pc == nullptr) {
     66    out = nullptr;
     67    return false;
     68  }
     69 
     70  // This allocates a char* array.
     71  char** frame_strings = backtrace_symbols(const_cast<void**>(&pc), 1);
     72 
     73  if (frame_strings == nullptr) return false;
     74 
     75  std::string symbol = debugging_internal::GetSymbolString(frame_strings[0]);
     76  free(frame_strings);
     77 
     78  char tmp_buf[1024];
     79  if (debugging_internal::Demangle(symbol.c_str(), tmp_buf, sizeof(tmp_buf))) {
     80    size_t len = strlen(tmp_buf);
     81    if (len + 1 <= static_cast<size_t>(out_size)) {  // +1 for '\0'
     82      assert(len < sizeof(tmp_buf));
     83      memmove(out, tmp_buf, len + 1);
     84    }
     85  } else {
     86    strncpy(out, symbol.c_str(), static_cast<size_t>(out_size));
     87  }
     88 
     89  if (out[out_size - 1] != '\0') {
     90    // strncpy() does not '\0' terminate when it truncates.
     91    static constexpr char kEllipsis[] = "...";
     92    size_t ellipsis_size =
     93        std::min(sizeof(kEllipsis) - 1, static_cast<size_t>(out_size) - 1);
     94    memcpy(out + out_size - ellipsis_size - 1, kEllipsis, ellipsis_size);
     95    out[out_size - 1] = '\0';
     96  }
     97 
     98  return true;
     99 }
    100 
    101 ABSL_NAMESPACE_END
    102 }  // namespace absl