1/*	$NetBSD: dehumanize_number.c,v 1.2 2007/12/14 17:32:47 xtraeme Exp $	*/
2
3/*
4 * Copyright (c) 2005, 2006 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Julio M. Merino Vidal, developed as part of Google's Summer of Code
9 * 2005 program.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32#include <sys/cdefs.h>
33#if defined(LIBC_SCCS) && !defined(lint)
34__RCSID("$NetBSD: dehumanize_number.c,v 1.2 2007/12/14 17:32:47 xtraeme Exp $");
35#endif /* LIBC_SCCS and not lint */
36
37#include "namespace.h"
38#include <inttypes.h>
39#include <ctype.h>
40#include <stdlib.h>
41#include <string.h>
42#include <errno.h>
43#include <limits.h>
44
45/*
46 * Converts the number given in 'str', which may be given in a humanized
47 * form (as described in humanize_number(3), but with some limitations),
48 * to an int64_t without units.
49 * In case of success, 0 is returned and *size holds the value.
50 * Otherwise, -1 is returned and *size is untouched.
51 *
52 * TODO: Internationalization, SI units.
53 */
54int
55dehumanize_number(const char *str, int64_t *size)
56{
57	char *ep, unit;
58	const char *delimit;
59	long multiplier;
60	long long tmp, tmp2;
61	size_t len;
62
63	len = strlen(str);
64	if (len == 0) {
65		errno = EINVAL;
66		return -1;
67	}
68
69	multiplier = 1;
70
71	unit = str[len - 1];
72	if (isalpha((unsigned char)unit)) {
73		switch (tolower((unsigned char)unit)) {
74		case 'b':
75			multiplier = 1;
76			break;
77
78		case 'k':
79			multiplier = 1024;
80			break;
81
82		case 'm':
83			multiplier = 1024 * 1024;
84			break;
85
86		case 'g':
87			multiplier = 1024 * 1024 * 1024;
88			break;
89
90		default:
91			errno = EINVAL;
92			return -1; /* Invalid suffix. */
93		}
94
95		delimit = &str[len - 1];
96	} else
97		delimit = NULL;
98
99	errno = 0;
100	tmp = strtoll(str, &ep, 10);
101	if (str[0] == '\0' || (ep != delimit && *ep != '\0'))
102		return -1; /* Not a number. */
103	else if (errno == ERANGE && (tmp == LLONG_MAX || tmp == LLONG_MIN))
104		return -1; /* Out of range. */
105
106	tmp2 = tmp * multiplier;
107	tmp2 = tmp2 / multiplier;
108	if (tmp != tmp2) {
109		errno = ERANGE;
110		return -1; /* Out of range. */
111	}
112	*size = tmp * multiplier;
113
114	return 0;
115}
116