mdw@git.distorted.org.uk Git - ssr/blob - StraySrc/Libraries/Steel/c/exception

   1 /*
   2  * Exception
   3  *  Handles odd errors in Steel programs
   4  *
   5  * 1.00 (24 September 1993)
   6  *
   7  * © 1993-1998 Straylight
   8  */
   9
  10 /*----- Licensing note ----------------------------------------------------*
  11  *
  12  * This file is part of Straylight's Steel library.
  13  *
  14  * Steel is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2, or (at your option)
  17  * any later version.
  18  *
  19  * Steel is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with Steel.  If not, write to the Free Software Foundation,
  26  * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 #include <stdarg.h>
  30 #include <stdio.h>
  31 #include <stdlib.h>
  32 #include "msgs.h"
  33 #include "exception.h"
  34 #include "wimpt.h"
  35 #include "werr.h"
  36 #include "visdelay.h"
  37
  38 #ifndef BOOL
  39 #define BOOL int
  40 #define TRUE 1
  41 #define FALSE 0
  42 #endif
  43
  44 static BOOL exception__handled;
  45 static int *exception__handler;
  46
  47 /*
  48  * int exception_registerHandler(exception_handler env)
  49  *
  50  * Use
  51  *  Registers the current point as being a sensible place to go after an
  52  *  exception.  This is implemented as a macro for the simple reason that
  53  *  things tend to go a tad wrong if you define your exception_handlers in a
  54  *  function and then return.
  55  *
  56  * Parameters
  57  *  exception_handler env == an undefined variable of the type
  58  *    exception_handler.
  59  */
  60
  61 #ifndef exception_registerHandler
  62 #define exception_registerHandler(env) \
  63   (exception__registerHandler((env),setjmp(env)))
  64 #endif
  65
  66 /*
  67  * void exception_generate(char *message,...)
  68  *
  69  * Use
  70  *  Generates a Steel exception, to be handled in an appropriate manner.
  71  *
  72  * Parameters
  73  *  char *message == printf()-type format string
  74  */
  75
  76 void exception_generate(char *message,...)
  77 {
  78   char buffer[256];
  79   va_list ap;
  80   va_start(ap,message);
  81   vsprintf(buffer,message,ap);
  82   va_end(ap);
  83   visdelay_suspend(); /* It doesn't mind if we suspend indefinitely */
  84   if (exception__handled==FALSE)
  85   {
  86     werr(FALSE,msgs_lookup("excFATAL:Fatal internal error: '%s'"),buffer);
  87     exit(1);
  88   }
  89   else
  90   {
  91     if (werr_error((wimpt_options() & wimpt_ONOBACKTRACE) ? 2 : 3,
  92                    msgs_lookup("excSEV:Internal error: '%s'.  Click OK "
  93                                "to continue, or Cancel to quit %s."),
  94                    buffer,
  95                    wimpt_programname())==0)
  96     {
  97       if (werr_error(2,
  98                      msgs_lookup("excAYS:Are you sure you want to quit %s?  "
  99                                  "Click OK to continue, or Cancel to quit."),
 100                      wimpt_programname())==0)
 101       {
 102         exit(1);
 103       }
 104       else
 105         longjmp(exception__handler,1);
 106     }
 107     else
 108       longjmp(exception__handler,1);
 109   }
 110 }
 111
 112 /*
 113  * int exception__registerHandler(jmp_buf handler)
 114  *
 115  * Use
 116  *  This routine is for the use of exception segment only, and should not be
 117  *  called from your code.
 118  */
 119
 120 int exception__registerHandler(jmp_buf handler,int result)
 121 {
 122   if (result==0)
 123   {
 124     exception__handled=TRUE;
 125     exception__handler=handler;
 126   }
 127   return (result);
 128 }