Further simplify the code, and update the manpage.

Submitted by:	Christoph Mallon <christoph.mallon@gmx.de>
This commit is contained in:
Dag-Erling Smørgrav 2010-08-15 18:32:06 +00:00
parent fb26ece72c
commit a2e0c5ae31
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=211343
2 changed files with 32 additions and 31 deletions

View file

@ -25,7 +25,7 @@
.\"
.\" $FreeBSD$
.\"
.Dd April 16, 2007
.Dd August 15, 2010
.Dt EXPAND_NUMBER 3
.Os
.Sh NAME
@ -37,14 +37,14 @@
.In libutil.h
.Ft int
.Fo expand_number
.Fa "const char *buf" "int64_t *num"
.Fa "const char *buf" "uint64_t *num"
.Fc
.Sh DESCRIPTION
The
.Fn expand_number
function unformats the
.Fa buf
string and stores a signed 64-bit quantity at address pointed out by the
string and stores a unsigned 64-bit quantity at address pointed out by the
.Fa num
argument.
.Pp

View file

@ -36,7 +36,7 @@ __FBSDID("$FreeBSD$");
#include <stdint.h>
/*
* Convert an expression of the following forms to a int64_t.
* Convert an expression of the following forms to a uint64_t.
* 1) A positive decimal number.
* 2) A positive decimal number followed by a 'b' or 'B' (mult by 1).
* 3) A positive decimal number followed by a 'k' or 'K' (mult by 1 << 10).
@ -50,6 +50,7 @@ int
expand_number(const char *buf, uint64_t *num)
{
uint64_t number;
unsigned shift;
char *endptr;
number = strtoumax(buf, &endptr, 0);
@ -60,41 +61,41 @@ expand_number(const char *buf, uint64_t *num)
return (-1);
}
if (*endptr == '\0') {
/* No unit. */
*num = number;
return (0);
}
#define SHIFT(n, b) \
do { if (((n << b) >> b) != n) goto overflow; n <<= b; } while (0)
switch (tolower((unsigned char)*endptr)) {
case 'e':
SHIFT(number, 10);
case 'p':
SHIFT(number, 10);
case 't':
SHIFT(number, 10);
case 'g':
SHIFT(number, 10);
case 'm':
SHIFT(number, 10);
case 'k':
SHIFT(number, 10);
case 'b':
shift = 60;
break;
case 'p':
shift = 50;
break;
case 't':
shift = 40;
break;
case 'g':
shift = 30;
break;
case 'm':
shift = 20;
break;
case 'k':
shift = 10;
break;
case 'b':
case '\0': /* No unit. */
*num = number;
return (0);
default:
/* Unrecognized unit. */
errno = EINVAL;
return (-1);
}
*num = number;
return (0);
if ((number << shift) >> shift != number) {
/* Overflow */
errno = ERANGE;
return (-1);
}
overflow:
/* Overflow */
errno = ERANGE;
return (-1);
*num = number << shift;
return (0);
}