heron/common/src/cpp/errors/gexception.h

/*
 * Copyright 2015 Twitter, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#if !defined(__GEXCEPTION_H)
#define __GEXCEPTION_H

/**
 * Singleton object which installs a global exception handler.
 *
 * When an object of this type is created globally, it will install itself
 * as the default exception handler, and will print out the exception then
 * call abort() if it is called.  It knows how to print out stack traces
 * for Lx_ErrorException.  If it is the first object instantiated, it will
 * also catch any exceptions thrown during construction of global objects.
 *
 * To use, put these two lines very first in the C++ file containing main():
 *
 *    #include "errhandler/gexception.h"
 *    Global_Exception_Handler       globalExceptionHandler;
 *
 * This object is a singleton, so creating more than one will not be harmful.
 *
 * This is based on an idea from IBM:
 *    http://www-128.ibm.com/developerworks/linux/library/l-cppexcep.html
 *
 */

namespace heron {
namespace error {

class Global_Exception_Handler {
 public:
  //! Create a singleton global exception handler to handle termination.
  Global_Exception_Handler();

  ~Global_Exception_Handler() {}

  //! Print out information about the current exception. Should be used in a catch block.
  static void print_backtrace();

 private:
  class Singleton_Exception_Handler {
   public:
    Singleton_Exception_Handler();

    ~Singleton_Exception_Handler() {}

    static void terminate(void);
  };
};
}  // namespace error
}  // namespace heron

#endif /* end of header file */