SC Spreadhseet Calculator on sysV/386

[Piercarlo Grandi]

On 28 Sep 90 16:49:08 GMT, richard at pegasus.com (Richard Foulk) said:

>>>Does anybody out there have sc running properly on sco unix or xenix
>>>sysV/386.

>Version 6.8 wouldn't compile with the AT&T compiler under ESIX-D.  "interp.c"
>bombed off with "Fatal error in /lib/comp."  GCC produced a working
>binary, but it did die with a core dump while I was going through the
>tutorial file provided with the package.

richard> On ISC 2.0.2 is works okay except that multiple divide-by-zero
richard> errors will cause it to core dump (I think it dies no the fifth
richard> one).

Here are a set of patches that eliminate some problems with sc 6.8, and
minimize the cases where divide-by-zero occur. In particular constant
expressions are only evaluated at load time, and non constant
expressions *are not* evaluated at load time, because this is both
useless and non sensical, because certain things may not be set up until
the entire spreadhseet has been loaded.

===================================================================
RCS file: interp.c,v
retrieving revision 6.8
diff -c -r6.8 interp.c
*** /tmp/,RCSt1a00165	Wed Sep 19 22:51:47 1990
--- interp.c	Wed Sep 19 22:40:30 1990
***************
*** 769,777 ****
  eval_fpe(signo) /* Trap for FPE errors in eval */
  int signo;
  {
  #ifdef IEEE_MATH
! 	(void)fpsetsticky((fp_except)0); 		/* Clear exception */
  #endif /* IEEE_MATH */
  	longjmp(fpe_save, 1);
  }
  
--- 769,782 ----
  eval_fpe(signo) /* Trap for FPE errors in eval */
  int signo;
  {
+ #ifdef i386
+ 	asm("	fnclex");
+ 	asm("	fwait");
+ #else
  #ifdef IEEE_MATH
! 	(void)fpsetsticky((fp_except)0);	/* Clear exception */
  #endif /* IEEE_MATH */
+ #endif
  	longjmp(fpe_save, 1);
  }
  
***************
*** 1130,1135 ****
--- 1135,1141 ----
  int i, j, *chgct;
  #endif
  {
+ 	(void) signal(SIGFPE, eval_fpe);
  	if (p->flags & is_strexpr) {
  	    char *v;
  	    if (setjmp(fpe_save)) {
***************
*** 1525,1569 ****
  struct enode *e;
  {
      double val;
  
!     exprerr = 0;
!     (void) signal(SIGFPE, eval_fpe);
!     if (setjmp(fpe_save)) {
! 	error ("Floating point exception in cell %s", v_name(v->row, v->col));
  	val = (double)0.0;
!     } else {
! 	val = eval(e);
!     }
!     (void) signal(SIGFPE, quit);
!     if (exprerr) {
! 	efree((struct ent *)0, e);
! 	return;
      }
!     if (constant(e)) {
! 	if (!loading)
! 	    v->v = val * prescale;
! 	else
! 	    v->v = val;
  	if (!(v->flags & is_strexpr)) {
              efree(v, v->expr);
  	    v->expr = (struct enode *)0;
  	}
  	efree((struct ent *)0, e);
-         v->flags |= (is_changed|is_valid);
-         changed++;
-         modflg++;
- 	return;
      }
!     efree (v, v->expr);
!     v->expr = e;
!     v->flags |= (is_changed|is_valid);
!     v->flags &= ~is_strexpr;
  
  #ifdef EXPRTREE
!     totoptree(v);
  #endif
!     changed++;
!     modflg++;
  }
  
  void
--- 1531,1581 ----
  struct enode *e;
  {
      double val;
+     unsigned isconstant = constant(e);
  
!     if (loading && !isconstant)
  	val = (double)0.0;
!     else
!     {
! 	exprerr = 0;
! 	(void) signal(SIGFPE, eval_fpe);
! 	if (setjmp(fpe_save)) {
! 	    error ("Floating point exception in cell %s", v_name(v->row, v->col));
! 	    val = (double)0.0;
! 	} else {
! 	    val = eval(e);
! 	}
! 	(void) signal(SIGFPE, quit);
! 	if (exprerr) {
! 	    efree((struct ent *)0, e);
! 	    return;
! 	}
      }
! 
!     if (isconstant) {
! 	if (!loading && prescale < (double)0.9999999)
! 	    val *= prescale;
! 	v->v = val;
! 
  	if (!(v->flags & is_strexpr)) {
              efree(v, v->expr);
  	    v->expr = (struct enode *)0;
  	}
  	efree((struct ent *)0, e);
      }
!     else
!     {
! 	efree (v, v->expr);
! 	v->expr = e;
! 	v->flags &= ~is_strexpr;
  
  #ifdef EXPRTREE
! 	totoptree(v);
  #endif
!     }
! 
!     v->flags |= (is_changed|is_valid);
!     changed++; modflg++;
  }
  
  void
===================================================================
RCS file: lex.c,v
retrieving revision 6.8
diff -c -r6.8 lex.c
*** /tmp/,RCSt1a00165	Wed Sep 19 22:51:52 1990
--- lex.c	Mon Sep 17 11:06:40 1990
***************
*** 56,61 ****
--- 56,78 ----
  jmp_buf wakeup;
  jmp_buf fpe_buf;
  
+ #ifdef SIGVOID
+ void
+ #endif
+ fpe_trap(signo)
+ int signo;
+ {
+ #ifdef i386
+ 	asm("	fnclex");
+ 	asm("	fwait");
+ #else
+ #ifdef IEEE_MATH
+ 	(void)fpsetsticky((fp_except)0);	/* Clear exception */
+ #endif /* IEEE_MATH */
+ #endif
+     longjmp(fpe_buf, 1);
+ }
+ 
  struct key {
      char *key;
      int val;
***************
*** 136,146 ****
  	    }
  	}
      } else if ((*p == '.') || isdigit(*p)) {
! 	double v = 0;
  	int temp;
  	char *nstart = p;
  	if (*p != '.') {
! 	    do v = v*10 + (double)(*p-'0');
  	    while (isdigit(*++p));
  	}
  	if (*p=='.' || *p == 'e' || *p == 'E') {
--- 153,177 ----
  	    }
  	}
      } else if ((*p == '.') || isdigit(*p)) {
! #ifdef SIGVOID
! 	void (*sig_save)();
! #else
! 	int (*sig_save)();
! #endif
! 	double v = 0.0;
  	int temp;
  	char *nstart = p;
+ 
+ 	sig_save = signal(SIGFPE, fpe_trap);
+ 	if (setjmp(fpe_buf)) {
+ 	    (void) signal(SIGFPE, sig_save);
+ 	    yylval.fval = v;
+ 	    error("Floating point exception\n");
+ 	    return FNUMBER;
+ 	}
+ 
  	if (*p != '.') {
! 	    do v = v*10.0 + (double) ((unsigned) *p - '0');
  	    while (isdigit(*++p));
  	}
  	if (*p=='.' || *p == 'e' || *p == 'E') {
***************
*** 163,168 ****
--- 194,200 ----
  		}
  	    }
  	}
+ 	(void) signal(SIGFPE, sig_save);
      } else if (*p=='"') {
  	char *ptr;
          ptr = p+1;
***************
*** 539,557 ****
  time_out(signo)
  int signo;
  {
! #ifdef IEEE_MATH
! 	(void)fpsetsticky((fp_except)0); 		/* Clear exception */
! #endif /* IEEE_MATH */
!     longjmp(wakeup, -1);
! }
! 
! #ifdef SIGVOID
! void
! #endif
! fpe_trap(signo)
! int signo;
! {
!     longjmp(fpe_buf, 1);
  }
  
  /*
--- 571,577 ----
  time_out(signo)
  int signo;
  {
!     longjmp(wakeup, 1);
  }
  
  /*
--
Piercarlo "Peter" Grandi           | ARPA: pcg%uk.ac.aber.cs at nsfnet-relay.ac.uk
Dept of CS, UCW Aberystwyth        | UUCP: ...!mcsun!ukc!aber-cs!pcg
Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg at cs.aber.ac.uk