include/root/TException.h

0001 // @(#)root/base:$Id$
0002 // Author: Fons Rademakers   21/09/95
0003
0004 /*************************************************************************
0005  * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
0006  * All rights reserved.                                                  *
0007  *                                                                       *
0008  * For the licensing terms see $ROOTSYS/LICENSE.                         *
0009  * For the list of contributors see $ROOTSYS/README/CREDITS.             *
0010  *************************************************************************/
0011
0012 #ifndef ROOT_TException
0013 #define ROOT_TException
0014
0015
0016 //////////////////////////////////////////////////////////////////////////
0017 //                                                                      //
0018 // Exception Handling                                                   //
0019 //                                                                      //
0020 // Provide some macro's to simulate the coming C++ try, catch and throw //
0021 // exception handling functionality.                                    //
0022 //                                                                      //
0023 //////////////////////////////////////////////////////////////////////////
0024
0025 #include <setjmp.h>
0026
0027 #include <ROOT/RConfig.hxx>
0028 #include "DllImport.h"
0029
0030 struct ExceptionContext_t {
0031 #ifdef NEED_SIGJMP
0032    sigjmp_buf fBuf;
0033 #else
0034    jmp_buf fBuf;
0035 #endif
0036 };
0037
0038 #ifdef NEED_SIGJMP
0039 # define SETJMP(buf) sigsetjmp(buf,1)
0040 #else
0041 #define SETJMP(buf) setjmp(buf)
0042 #endif
0043
0044 #define RETRY \
0045    { \
0046       static ExceptionContext_t R__curr, *R__old = gException; \
0047       int R__code; \
0048       gException = &R__curr; \
0049       R__code = SETJMP(gException->fBuf); if (R__code) { }; {
0050
0051 #define TRY \
0052    { \
0053       static ExceptionContext_t R__curr, *R__old = gException; \
0054       int R__code; \
0055       gException = &R__curr; \
0056       if ((R__code = SETJMP(gException->fBuf)) == 0) {
0057
0058 #define CATCH(n) \
0059          gException = R__old; \
0060       } else { \
0061          int n = R__code; \
0062          gException = R__old;
0063
0064 #define ENDTRY \
0065       } \
0066       gException = R__old; \
0067    }
0068
0069 R__EXTERN ExceptionContext_t *gException;
0070
0071 R__EXTERN void Throw(int code);
0072
0073 class TExceptionHandler {
0074 public:
0075    virtual ~TExceptionHandler() {}
0076    virtual void HandleException(int sig) = 0;
0077 };
0078
0079 R__EXTERN TExceptionHandler* gExceptionHandler;
0080
0081 #endif