g3log/example/main_sigsegv.cpp

/** ==========================================================================
* 2011 by KjellKod.cc. This is PUBLIC DOMAIN to use at your own risk and comes
* with no warranties. This code is yours to share, use and modify with no
* strings attached and no restrictions or obligations.
 * 
 * For more information see g3log/LICENSE or refer refer to http://unlicense.org
* ============================================================================*/

#include "g2logworker.hpp"
#include "g2log.hpp"
#include <iomanip>
#include <thread>
#include <iostream>
#include <memory>
namespace
{
#if (defined(WIN32) || defined(_WIN32) || defined(__WIN32__))
const std::string path_to_log_file = "./";
#else
const std::string path_to_log_file = "/tmp/";
#endif
}

namespace example_fatal
{
  // on Ubunti this caused get a compiler warning with gcc4.6
  // from gcc 4.7.2 (at least) it causes a crash (as expected)
  // On windows it'll probably crash too.
  void tryToKillWithIllegalPrintout()
  {
    std::cout << "\n\n***** Be ready this last example may 'abort' if on Windows/Linux_gcc4.7 " << std::endl << std::flush;
    std::cout << "************************************************************\n\n" << std::endl << std::flush;
    std::this_thread::sleep_for(std::chrono::seconds(1));
    const std::string logging = "logging";
    LOGF(DEBUG, "ILLEGAL PRINTF_SYNTAX EXAMPLE. WILL GENERATE compiler warning.\n\nbadly formatted message:[Printf-type %s is the number 1 for many %s]", logging.c_str());
  }


  // The function above 'tryToKillWithIllegalPrintout' IS system / compiler dependent. Older compilers sometimes did NOT generate a SIGSEGV
  // fault as expected by the illegal printf-format usage. just in case we exit by zero division"
  void  killByZeroDivision(int value)
  {
    int zero = 0; // trying to fool the compiler to automatically warn
    LOG(INFO) << "This is a bad operation [value/zero] : " << value/zero;
  }
} // example fatal



int main(int argc, char** argv)
{
  double pi_d = 3.1415926535897932384626433832795;
  float pi_f = 3.1415926535897932384626433832795f;

  using namespace g2;

  std::unique_ptr<LogWorker> logworker{LogWorker::createWithNoSink()};
  auto sinkHandle = logworker->addSink(std2::make_unique<FileSink>(argv[0], path_to_log_file),
                                          &FileSink::fileWrite);

  initializeLogging(logworker.get());
  std::future<std::string> log_file_name = sinkHandle->call(&FileSink::fileName);
  std::cout << "*   This is an example of g2log. It WILL exit by a FATAL trigger" << std::endl;
  std::cout << "*   Please see the generated log and compare to the code at" << std::endl;
  std::cout << "*   g2log/test_example/main.cpp" << std::endl;
  std::cout << "*\n* Log file: [" << log_file_name.get() << "]\n\n" << std::endl;


  LOGF(INFO, "Hi log %d", 123);
  LOG(INFO) << "Test SLOG INFO";
  LOG(DEBUG) << "Test SLOG DEBUG";
  LOG(INFO) << "one: " << 1;
  LOG(INFO) << "two: " << 2;
  LOG(INFO) << "one and two: " << 1 << " and " << 2;
  LOG(DEBUG) << "float 2.14: " << 1000/2.14f;
  LOG(DEBUG) << "pi double: " << pi_d;
  LOG(DEBUG) << "pi float: " << pi_f;
  LOG(DEBUG) << "pi float (width 10): " << std::setprecision(10) << pi_f;
  LOGF(INFO, "pi float printf:%f", pi_f);

  //
  // START: LOG Entris that were in the CodeProject article
  //
  //LOG(UNKNOWN_LEVEL) << "This log attempt will cause a compiler error";

  LOG(INFO) << "Simple to use with streaming syntax, easy as abc or " << 123;
  LOGF(WARNING, "Printf-style syntax is also %s", "available");
  LOG_IF(INFO, (1 < 2)) << "If true this text will be logged";
  LOGF_IF(INFO, (1<2), "if %d<%d : then this text will be logged", 1,2);
  LOG_IF(FATAL, (2>3)) << "This message should NOT throw";
  LOGF(DEBUG, "This API is popular with some %s", "programmers");
  LOGF_IF(DEBUG, (1<2), "If true, then this %s will be logged", "message");

  // OK --- on Ubunti this caused get a compiler warning with gcc4.6
  // from gcc 4.7.2 (at least) it causes a crash (as expected)
  // On windows itll probably crash
  //example_fatal::tryToKillWithIllegalPrintout();

  int value = 1;    // system dependent but it SHOULD never reach this line
  example_fatal::killByZeroDivision(value);
  return 0;
}