C++ (Cpp) GetBacktraceData Examples

Example #1

File: UnwindPtrace.cpp Project: xinran505982/platform_system_core

bool UnwindPtrace::Unwind(size_t num_ignore_frames) {
  addr_space_ = unw_create_addr_space(&_UPT_accessors, 0);
  if (!addr_space_) {
    BACK_LOGW("unw_create_addr_space failed.");
    return false;
  }

  upt_info_ = reinterpret_cast<struct UPT_info*>(_UPT_create(backtrace_obj_->Tid()));
  if (!upt_info_) {
    BACK_LOGW("Failed to create upt info.");
    return false;
  }

  backtrace_t* backtrace = GetBacktraceData();
  backtrace->num_frames = 0;

  unw_cursor_t cursor;
  int ret = unw_init_remote(&cursor, addr_space_, upt_info_);
  if (ret < 0) {
    BACK_LOGW("unw_init_remote failed %d", ret);
    return false;
  }

  do {
    unw_word_t pc;
    ret = unw_get_reg(&cursor, UNW_REG_IP, &pc);
    if (ret < 0) {
      BACK_LOGW("Failed to read IP %d", ret);
      break;
    }
    unw_word_t sp;
    ret = unw_get_reg(&cursor, UNW_REG_SP, &sp);
    if (ret < 0) {
      BACK_LOGW("Failed to read SP %d", ret);
      break;
    }

    if (num_ignore_frames == 0) {
      size_t num_frames = backtrace->num_frames;
      backtrace_frame_data_t* frame = &backtrace->frames[num_frames];
      frame->pc = static_cast<uintptr_t>(pc);
      frame->sp = static_cast<uintptr_t>(sp);
      frame->stack_size = 0;
      frame->map_name = NULL;
      frame->map_offset = 0;
      frame->func_name = NULL;
      frame->func_offset = 0;

      if (num_frames > 0) {
        backtrace_frame_data_t* prev = &backtrace->frames[num_frames-1];
        prev->stack_size = frame->sp - prev->sp;
      }

      std::string func_name = backtrace_obj_->GetFunctionName(frame->pc, &frame->func_offset);
      if (!func_name.empty()) {
        frame->func_name = strdup(func_name.c_str());
      }

      uintptr_t map_start;
      frame->map_name = backtrace_obj_->GetMapName(frame->pc, &map_start);
      if (frame->map_name) {
        frame->map_offset = frame->pc - map_start;
      }

      backtrace->num_frames++;
    } else {
      num_ignore_frames--;
    }
    ret = unw_step (&cursor);
  } while (ret > 0 && backtrace->num_frames < MAX_BACKTRACE_FRAMES);

  return true;
}

Example #2

File: UnwindCurrent.cpp Project: c-ong/platform_system_core

bool UnwindCurrent::UnwindFromContext(size_t num_ignore_frames, bool resolve) {
  backtrace_t* backtrace = GetBacktraceData();
  backtrace->num_frames = 0;

  // The cursor structure is pretty large, do not put it on the stack.
  unw_cursor_t* cursor = new unw_cursor_t;
  int ret = unw_init_local(cursor, &context_);
  if (ret < 0) {
    ALOGW("UnwindCurrent::UnwindWithContext: unw_init_local failed %d\n", ret);
    return false;
  }

  do {
    unw_word_t pc;
    ret = unw_get_reg(cursor, UNW_REG_IP, &pc);
    if (ret < 0) {
      ALOGW("UnwindCurrent::UnwindWithContext: Failed to read IP %d\n", ret);
      break;
    }
    unw_word_t sp;
    ret = unw_get_reg(cursor, UNW_REG_SP, &sp);
    if (ret < 0) {
      ALOGW("UnwindCurrent::UnwindWithContext: Failed to read SP %d\n", ret);
      break;
    }

    if (num_ignore_frames == 0) {
      size_t num_frames = backtrace->num_frames;
      backtrace_frame_data_t* frame = &backtrace->frames[num_frames];
      frame->pc = static_cast<uintptr_t>(pc);
      frame->sp = static_cast<uintptr_t>(sp);
      frame->stack_size = 0;
      frame->map_name = NULL;
      frame->map_offset = 0;
      frame->func_name = NULL;
      frame->func_offset = 0;

      if (num_frames > 0) {
        // Set the stack size for the previous frame.
        backtrace_frame_data_t* prev = &backtrace->frames[num_frames-1];
        prev->stack_size = frame->sp - prev->sp;
      }

      if (resolve) {
        std::string func_name = backtrace_obj_->GetFunctionName(frame->pc, &frame->func_offset);
        if (!func_name.empty()) {
          frame->func_name = strdup(func_name.c_str());
        }

        uintptr_t map_start;
        frame->map_name = backtrace_obj_->GetMapName(frame->pc, &map_start);
        if (frame->map_name) {
          frame->map_offset = frame->pc - map_start;
        }
      }

      backtrace->num_frames++;
    } else {
      num_ignore_frames--;
    }
    ret = unw_step (cursor);
  } while (ret > 0 && backtrace->num_frames < MAX_BACKTRACE_FRAMES);

  delete cursor;
  return true;
}