src/signalhandler_unittest.cc

// Copyright (c) 2024, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
//     * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//     * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
//     * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
//
// Author: Satoru Takabayashi
//
// This is a helper binary for testing signalhandler.cc.  The actual test
// is done in signalhandler_unittest.sh.

#include <csignal>
#include <cstdio>
#include <cstdlib>
#include <sstream>
#include <string>
#include <thread>

#include "config.h"
#include "glog/logging.h"
#include "stacktrace.h"
#include "symbolize.h"

#if defined(HAVE_UNISTD_H)
#  include <unistd.h>
#endif
#ifdef GLOG_USE_GFLAGS
#  include <gflags/gflags.h>
using namespace GFLAGS_NAMESPACE;
#endif
#if defined(_MSC_VER)
#  include <io.h>  // write
#endif

using namespace google;

static void DieInThread(int* a) {
  std::ostringstream oss;
  oss << std::showbase << std::hex << std::this_thread::get_id();

  fprintf(stderr, "%s is dying\n", oss.str().c_str());
  int b = 1 / *a;
  fprintf(stderr, "We should have died: b=%d\n", b);
}

static void WriteToStdout(const char* data, size_t size) {
  if (write(fileno(stdout), data, size) < 0) {
    // Ignore errors.
  }
}

int main(int argc, char** argv) {
#if defined(HAVE_STACKTRACE) && defined(HAVE_SYMBOLIZE)
  InitGoogleLogging(argv[0]);
#  ifdef GLOG_USE_GFLAGS
  ParseCommandLineFlags(&argc, &argv, true);
#  endif
  InstallFailureSignalHandler();
  const std::string command = argc > 1 ? argv[1] : "none";
  if (command == "segv") {
    // We'll check if this is outputted.
    LOG(INFO) << "create the log file";
    LOG(INFO) << "a message before segv";
    // We assume 0xDEAD is not writable.
    int* a = (int*)0xDEAD;
    *a = 0;
  } else if (command == "loop") {
    fprintf(stderr, "looping\n");
    while (true)
      ;
  } else if (command == "die_in_thread") {
    std::thread t{&DieInThread, nullptr};
    t.join();
  } else if (command == "dump_to_stdout") {
    InstallFailureWriter(WriteToStdout);
    abort();
  } else if (command == "installed") {
    fprintf(stderr, "signal handler installed: %s\n",
            IsFailureSignalHandlerInstalled() ? "true" : "false");
  } else {
    // Tell the shell script
    puts("OK");
  }
#endif
  return 0;
}