LogSingleton.cc

   1 /*
   2  * Copyright (c) 2002, Robert Collins..
   3  *
   4  *     This program is free software; you can redistribute it and/or modify
   5  *     it under the terms of the GNU General Public License as published by
   6  *     the Free Software Foundation; either version 2 of the License, or
   7  *     (at your option) any later version.
   8  *
   9  *     A copy of the GNU General Public License can be found at
  10  *     http://www.gnu.org/
  11  *
  12  * Written by Robert Collins <rbtcollins@hotmail.com>
  13  *
  14  */
  15
  16 #include "LogSingleton.h"
  17 #include <stdexcept>
  18
  19 using namespace std;
  20
  21 /* Helper functions */
  22
  23 /* End of a Log comment */
  24 ostream& endLog(ostream& outs)
  25 {
  26   /* Doesn't seem to be any way around this */
  27   dynamic_cast<LogSingleton &>(outs).endEntry();
  28   return outs;
  29 }
  30
  31 /* The LogSingleton class */
  32
  33 LogSingleton * LogSingleton::theInstance(0);
  34
  35 LogSingleton::LogSingleton(std::streambuf* aStream) : ios (aStream), ostream (aStream)
  36 {
  37     ios::init (aStream);
  38 }
  39 LogSingleton::~LogSingleton(){}
  40
  41 LogSingleton &
  42 LogSingleton::GetInstance()
  43 {
  44   if (!theInstance)
  45     throw new invalid_argument ("No instance has been set!");
  46   return *theInstance;
  47 }
  48
  49 void
  50 LogSingleton::SetInstance(LogSingleton &newInstance)
  51 {
  52   theInstance = &newInstance;
  53 }
  54
  55 #if 0
  56 // Logging class. Default logging level is PLAIN.
  57 class LogSingleton : public ostream
  58 {
  59 public:
  60   // Singleton support
  61   /* Some platforms don't call destructors. So this call exists
  62    * which guarantees to flush any log data...
  63    * but doesn't call generic C++ destructors
  64    */
  65   virtual void exit (int const exit_code) __attribute__ ((noreturn));
  66   // get a specific verbosity stream.
  67   virtual ostream &operator() (enum log_level level);
  68
  69   friend ostream& endLog(ostream& outs);
  70
  71 protected:
  72   LogSingleton (LogSingleton const &); // no copy constructor
  73   LogSingleton &operator = (LogSingleton const&); // no assignment operator
  74   void endEntry(); // the current in-progress entry is complete.
  75 private:
  76   static LogSingleton *theInstance;
  77 };
  78 #endif