Error.h

//-*-C++-*-
/***************************************************************************
 *
 *   Copyright (C) 2004 by Willem van Straten
 *   Licensed under the Academic Free License version 2.1
 *
 ***************************************************************************/
 
// psrchive/Util/units/Error.h
 
#ifndef __Error_h
#define __Error_h
 
#include <iostream>
#include <vector>
#include <string>

enum ErrorCode {
  Undefined,
  BadAllocation,
  InvalidPointer,
  InvalidParam,
  InvalidState,
  InvalidRange,
  FileNotFound,
  EndOfFile,
  FailedCall,
  FailedSys,
  HelpMessage
};

/*
  It is useful to throw an exception with both an error code and a
  text message.  As well, on catching an exception, it is useful if a
  function or method can add its name to an "exception stack",
  enabling the error to be traced back to its origin.  The static
  method, Error::handle_signals(), may also be invoked so that signal
  interrupts, such as SIGFPE and SIGSEGV, will be intercepted and an
  Error exception will be thrown. 
*/
class Error {
 
  public:

  static const char* err2str (ErrorCode code);

  static bool verbose;

  static bool complete_abort;

  Error (ErrorCode c, std::string func, const char* msg=0, ...);

  Error (ErrorCode c, std::string func, std::string msg);
  
  virtual ~Error ();

  const Error& operator += (const char* func);
  
  const Error& operator += (const std::string& func);
  
  virtual void report (std::ostream& ostr) const;
  
  virtual std::string warning () const;

  const std::string get_message() const;

  ErrorCode get_code () const { return code; }

  template<class T>
  friend Error& operator<< (Error& error, const T& t);
 
protected:

  ErrorCode code;
  std::string message;
  std::vector<std::string> functions;

  Error ();

  void errno_check ();
  
  void construct (ErrorCode c, const std::string& func, const char* msg);
};

std::ostream& operator<< (std::ostream& ostr, const Error& error);
 
#include "tostring.h"
 
template<class T>
Error& operator<< (Error& error, const T& t)
{
  error.message += tostring(t);
  return error;
}
 
#endif