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Latest patch from vodz. Adds a check for divide by zero in the posix

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math suport, cleaner math syntax error checking, moves redundant signal
string tables (from kill and ash) into libbb and provides a few
cleanups elsewhere.
This commit is contained in:
Eric Andersen
2001-08-02 05:02:46 +00:00
parent 2d91deba45
commit 3450636169
17 changed files with 187 additions and 570 deletions
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33
libbb/arith.c
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@@ -119,20 +119,26 @@ static short arith_apply(operator op, long *numstack, long **numstackptr)
NUMPTR[-1] = (NUMPTR[-1] <= *NUMPTR);
else if (op == TOK_MUL)
NUMPTR[-1] *= *NUMPTR;
else if (op == TOK_DIV)
else if (op == TOK_DIV) {
if(*NUMPTR==0)
return -2;
NUMPTR[-1] /= *NUMPTR;
else if (op == TOK_REM)
}
else if (op == TOK_REM) {
if(*NUMPTR==0)
return -2;
NUMPTR[-1] %= *NUMPTR;
}
else if (op == TOK_ADD)
NUMPTR[-1] += *NUMPTR;
else if (op == TOK_SUB)
NUMPTR[-1] -= *NUMPTR;
}
return 0;
err: return(1);
err: return(-1);
}
extern long arith (const char *startbuf)
extern long arith (const char *startbuf, int *errcode)
{
register char arithval;
const char *expr = startbuf;
@@ -142,8 +148,9 @@ extern long arith (const char *startbuf)
unsigned char prec;
long *numstack, *numstackptr;
operator *stack = alloca(datasizes * sizeof(operator)), *stackptr = stack;
*errcode = 0;
numstack = alloca((datasizes/2+1)*sizeof(long)), numstackptr = numstack;
while ((arithval = *expr)) {
@@ -163,7 +170,8 @@ extern long arith (const char *startbuf)
op = *--stackptr;
if (op == TOK_LPAREN)
goto prologue;
if(ARITH_APPLY(op)) goto err;
*errcode = ARITH_APPLY(op);
if(*errcode) return *errcode;
}
goto err; /* Mismatched parens */
} if (arithval == '|') {
@@ -231,17 +239,22 @@ extern long arith (const char *startbuf)
prec = PREC(op);
if (prec != UNARYPREC)
while (stackptr != stack && PREC(stackptr[-1]) >= prec)
if(ARITH_APPLY(*--stackptr)) goto err;
while (stackptr != stack && PREC(stackptr[-1]) >= prec) {
*errcode = ARITH_APPLY(*--stackptr);
if(*errcode) return *errcode;
}
*stackptr++ = op;
lasttok = op;
prologue: ++expr;
} /* yay */
while (stackptr != stack)
if(ARITH_APPLY(*--stackptr)) goto err;
while (stackptr != stack) {
*errcode = ARITH_APPLY(*--stackptr);
if(*errcode) return *errcode;
}
if (numstackptr != numstack+1) {
err:
*errcode = -1;
return -1;
/* NOTREACHED */
}