mrw-cxx/mrw/autostacktracestderr.cpp

/** @file

    $Id$

    $Date$
    $Author$

    @copy © Marc Wäckerlin
    @license LGPL, see file <a href="license.html">COPYING</a>

    $Log$
    Revision 1.3  2004/08/28 16:21:25  marc
    mrw-c++-0.92 (mrw)
    - new file: version.cpp
    - new file header for all sources
    - work around warning in mrw::auto<T>
    - possibility to compile without log4cxx
    - work around bugs in demangle.h and libiberty.h
    - corrections in documentation
    - added simple tracing mechanism
    - more warnings
    - small corrections in Auto<>::Free and a new test for it
    - possibility to compile without stack trace

*/
#include <mrw/stacktrace.hpp>
#include <mrw/exception.hpp>
#include <exception>
#include <iostream>

namespace mrw {

  /** @addtogroup StackTrace */
  //@{

  /** @defgroup AutoTrace Automated Unexpected Handler with Stack Trace

      @brief Don't care about the unexpected handler, let the library
      do all the repetitive work for you.

      For all your programs it is recommended to implement an identical
      unexpected handler, that rethrows, catches the @c
      mrw::exception, @c std::exception and all unknown exceptions,
      traces them and finally quits with a throw of a @c
      atd::bad_exception. The only thing that may be different from
      project to project is, how tracing is done. The MRW C++ Class
      Library provides you with additional libraries you can link
      to. By linking to the library, you get an unexpected handler for
      free: You don't need to add a single line of code, just link to
      one more library! The libraries differ in how tracing is done.

      The Implementation is done with a static instance of a class that
      sets the unexpected handler in the constructor.

      @section trcstderr Trace using std::cerr

      If you link to the library @c libmrwexcstderr using a linker
      option such as: @c -lmrwexcstderr, then an unexpected handler is
      registered, that traces to the standard error stream @c
      std::cerr. You don't need to change a single line in your code!
  */
  //@{
  
  /** @brief unexpected handler, that traces to @c std::cerr

      The unexpected handler is installed automatically when you link
      to @c -lmrwexcstderr. The implementation of this unexpected
      handler is as follows:

      @code
  void unexpected_stderr() {
    std::cerr<<"UNEXPECTED EXCEPTION: ----------------------------"<<std::endl;
    try {
      throw;
    } catch (const mrw::exception& x) {
      StackTrace::createSymtable();
      std::cerr<<"---------- Reason:"<<std::endl
               <<x.what()<<std::endl
               <<"---------- Stack:"<<std::endl
               <<x.stacktrace()<<std::endl;
    } catch (const std::exception& x) {
      std::cerr<<"---------- Reason:"<<std::endl
               <<x.what()<<std::endl
               <<"---------- Stack:  **** not available ****"<<std::endl;
    } catch (...) {
      std::cerr<<"---------- Reason: **** not available ****"<<std::endl
               <<"---------- Stack:  **** not available ****"<<std::endl;
    }
    std::cerr<<"-------------------------------------------------"<<std::endl;
    throw std::bad_exception();
  }
      @endcode

  */
  void unexpected_stderr() {
    std::cerr<<"UNEXPECTED EXCEPTION: ----------------------------"<<std::endl;
    try {
      throw;
    } catch (const mrw::exception& x) {
      StackTrace::createSymtable();
      std::cerr<<"---------- Reason:"<<std::endl
               <<x.what()<<std::endl
               <<"---------- Stack:"<<std::endl
               <<x.stacktrace()<<std::endl;
    } catch (const std::exception& x) {
      std::cerr<<"---------- Reason:"<<std::endl
               <<x.what()<<std::endl
               <<"---------- Stack:  **** not available ****"<<std::endl;
    } catch (...) {
      std::cerr<<"---------- Reason: **** not available ****"<<std::endl
               <<"---------- Stack:  **** not available ****"<<std::endl;
    }
    std::cerr<<"-------------------------------------------------"<<std::endl;
    throw std::bad_exception();
  }

  //@}
  //@}

  class AutoStackTrace {
    public:
    AutoStackTrace() {
      std::set_unexpected(&mrw::unexpected_stderr);
    }
  };

  // initialize stack traces (load symbols)
  static AutoStackTrace _autoStackTrace;

}