freebsd-nq/lib/libutil/expand_number.c
Sergey Kandaurov 7261b203c6 Reset errno before strtoumax() call to properly detect ERANGE.
Restore saved errno if strtoumax() call is successful.

Reported by:	ache
Reviewed by:	jilles
MFC after:	1 week
2013-08-21 22:37:15 +00:00

113 lines
3.1 KiB
C

/*-
* Copyright (c) 2007 Eric Anderson <anderson@FreeBSD.org>
* Copyright (c) 2007 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <ctype.h>
#include <errno.h>
#include <inttypes.h>
#include <libutil.h>
#include <stdint.h>
/*
* 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).
* 4) A positive decimal number followed by a 'm' or 'M' (mult by 1 << 20).
* 5) A positive decimal number followed by a 'g' or 'G' (mult by 1 << 30).
* 6) A positive decimal number followed by a 't' or 'T' (mult by 1 << 40).
* 7) A positive decimal number followed by a 'p' or 'P' (mult by 1 << 50).
* 8) A positive decimal number followed by a 'e' or 'E' (mult by 1 << 60).
*/
int
expand_number(const char *buf, uint64_t *num)
{
uint64_t number;
int saved_errno;
unsigned shift;
char *endptr;
saved_errno = errno;
errno = 0;
number = strtoumax(buf, &endptr, 0);
if (number == UINTMAX_MAX && errno == ERANGE) {
return (-1);
}
if (errno == 0)
errno = saved_errno;
if (endptr == buf) {
/* No valid digits. */
errno = EINVAL;
return (-1);
}
switch (tolower((unsigned char)*endptr)) {
case 'e':
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);
}
if ((number << shift) >> shift != number) {
/* Overflow */
errno = ERANGE;
return (-1);
}
*num = number << shift;
return (0);
}