Import fmt_scaled.c rev 1.16 from OpenBSD.

Fix overly-conservative overflow checks on mulitplications and add checks
on additions.  This allows scan_scaled to work up to +/-LLONG_MAX (LLONG_MIN
will still be flagged as a range error).  ok millert@
This commit is contained in:
Darren Tucker 2017-03-29 16:34:44 +11:00
parent c73a229e4e
commit 282cad2240
1 changed files with 11 additions and 3 deletions

View File

@ -1,4 +1,4 @@
/* $OpenBSD: fmt_scaled.c,v 1.15 2017/03/15 05:25:56 dtucker Exp $ */
/* $OpenBSD: fmt_scaled.c,v 1.16 2017/03/16 02:40:46 dtucker Exp $ */
/*
* Copyright (c) 2001, 2002, 2003 Ian F. Darwin. All rights reserved.
@ -125,22 +125,30 @@ scan_scaled(char *scaled, long long *result)
/* ignore extra fractional digits */
continue;
fract_digits++; /* for later scaling */
if (fpart >= LLONG_MAX / 10) {
if (fpart > LLONG_MAX / 10) {
errno = ERANGE;
return -1;
}
fpart *= 10;
if (i > LLONG_MAX - fpart) {
errno = ERANGE;
return -1;
}
fpart += i;
} else { /* normal digit */
if (++ndigits >= MAX_DIGITS) {
errno = ERANGE;
return -1;
}
if (whole >= LLONG_MAX / 10) {
if (whole > LLONG_MAX / 10) {
errno = ERANGE;
return -1;
}
whole *= 10;
if (i > LLONG_MAX - whole) {
errno = ERANGE;
return -1;
}
whole += i;
}
}