1/* $NetBSD: _strtoul.h,v 1.7 2013/05/17 12:55:56 joerg Exp $ */
2
3/*-
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 * Original version ID:
32 * NetBSD: src/lib/libc/locale/_wcstoul.h,v 1.2 2003/08/07 16:43:03 agc Exp
33 */
34
35#include <bmk-core/null.h>
36#include <bmk-core/platform.h>
37#include <bmk-core/string.h>
38
39/*
40 * Technically this module is meant to be used as an includable template,
41 * but for now we only need strtoul, so just hardcode it.
42 */
43
44#define _FUNCNAME bmk_strtoul
45#define __UINT unsigned long
46#define __UINT_MAX (2UL*__LONG_MAX__+1UL)
47
48#define __UNCONST(x) ((void *)(unsigned long)(x))
49
50/*
51 * function template for strtoul, strtoull and strtoumax.
52 *
53 * parameters:
54 *	_FUNCNAME  : function name
55 *      __UINT     : return type
56 *      __UINT_MAX : upper limit of the return type
57 */
58__UINT
59_FUNCNAME(const char *nptr, char **endptr, int base)
60{
61	const char *s;
62	__UINT acc, cutoff;
63	unsigned char c;
64	int i, neg, any, cutlim;
65
66	/* check base value */
67	if (base && (base < 2 || base > 36)) {
68		bmk_platform_halt("invalid base to strtoul");
69	}
70
71	/*
72	 * Skip white space and pick up leading +/- sign if any.
73	 * If base is 0, allow 0x for hex and 0 for octal, else
74	 * assume decimal; if base is already 16, allow 0x.
75	 */
76	s = nptr;
77	do {
78		c = *s++;
79	} while (c == ' '|| (c >= '\t' && c <= '\r'));
80	if (c == '-') {
81		neg = 1;
82		c = *s++;
83	} else {
84		neg = 0;
85		if (c == '+')
86			c = *s++;
87	}
88	if ((base == 0 || base == 16) &&
89	    c == '0' && (*s == 'x' || *s == 'X')) {
90		c = s[1];
91		s += 2;
92		base = 16;
93	}
94	if (base == 0)
95		base = (c == '0' ? 8 : 10);
96
97	/*
98	 * See strtol for comments as to the logic used.
99	 */
100	cutoff = ((__UINT)__UINT_MAX / (__UINT)base);
101	cutlim = (int)((__UINT)__UINT_MAX % (__UINT)base);
102	for (acc = 0, any = 0;; c = *s++) {
103		if (c >= '0' && c <= '9')
104			i = c - '0';
105		else if (c >= 'a' && c <= 'z')
106			i = (c - 'a') + 10;
107		else if (c >= 'A' && c <= 'Z')
108			i = (c - 'A') + 10;
109		else
110			break;
111		if (i >= base)
112			break;
113		if (any < 0)
114			continue;
115		if (acc > cutoff || (acc == cutoff && i > cutlim)) {
116			acc = __UINT_MAX;
117			any = 0;
118			break;
119		} else {
120			any = 1;
121			acc *= (__UINT)base;
122			acc += i;
123		}
124	}
125	if (neg && any > 0)
126		acc = -acc;
127	if (endptr != NULL)
128		/* LINTED interface specification */
129		*endptr = __UNCONST(any ? s - 1 : nptr);
130	return(acc);
131}
132