1 /*
2 FUNCTION
3 	<<strtoul>>, <<strtoul_l>>---string to unsigned long
4 
5 INDEX
6 	strtoul
7 
8 INDEX
9 	strtoul_l
10 
11 INDEX
12 	_strtoul_r
13 
14 SYNOPSIS
15 	#include <stdlib.h>
16         unsigned long strtoul(const char *restrict <[s]>,
17 			      char **restrict <[ptr]>, int <[base]>);
18 
19 	#include <stdlib.h>
20         unsigned long strtoul_l(const char *restrict <[s]>,
21 				char **restrict <[ptr]>, int <[base]>,
22 				locale_t <[locale]>);
23 
24         unsigned long _strtoul_r(void *<[reent]>, const char *restrict <[s]>,
25 				 char **restrict <[ptr]>, int <[base]>);
26 
27 DESCRIPTION
28 The function <<strtoul>> converts the string <<*<[s]>>> to
29 an <<unsigned long>>. First, it breaks down the string into three parts:
30 leading whitespace, which is ignored; a subject string consisting
31 of the digits meaningful in the radix specified by <[base]>
32 (for example, <<0>> through <<7>> if the value of <[base]> is 8);
33 and a trailing portion consisting of one or more unparseable characters,
34 which always includes the terminating null character. Then, it attempts
35 to convert the subject string into an unsigned long integer, and returns the
36 result.
37 
38 If the value of <[base]> is zero, the subject string is expected to look
39 like a normal C integer constant (save that no optional sign is permitted):
40 a possible <<0x>> indicating hexadecimal radix, and a number.
41 If <[base]> is between 2 and 36, the expected form of the subject is a
42 sequence of digits (which may include letters, depending on the
43 base) representing an integer in the radix specified by <[base]>.
44 The letters <<a>>--<<z>> (or <<A>>--<<Z>>) are used as digits valued from
45 10 to 35. If <[base]> is 16, a leading <<0x>> is permitted.
46 
47 The subject sequence is the longest initial sequence of the input
48 string that has the expected form, starting with the first
49 non-whitespace character.  If the string is empty or consists entirely
50 of whitespace, or if the first non-whitespace character is not a
51 permissible digit, the subject string is empty.
52 
53 If the subject string is acceptable, and the value of <[base]> is zero,
54 <<strtoul>> attempts to determine the radix from the input string. A
55 string with a leading <<0x>> is treated as a hexadecimal value; a string with
56 a leading <<0>> and no <<x>> is treated as octal; all other strings are
57 treated as decimal. If <[base]> is between 2 and 36, it is used as the
58 conversion radix, as described above. Finally, a pointer to the first
59 character past the converted subject string is stored in <[ptr]>, if
60 <[ptr]> is not <<NULL>>.
61 
62 If the subject string is empty (that is, if <<*>><[s]> does not start
63 with a substring in acceptable form), no conversion
64 is performed and the value of <[s]> is stored in <[ptr]> (if <[ptr]> is
65 not <<NULL>>).
66 
67 <<strtoul_l>> is like <<strtoul>> but performs the conversion based on the
68 locale specified by the locale object locale.  If <[locale]> is
69 LC_GLOBAL_LOCALE or not a valid locale object, the behaviour is undefined.
70 
71 The alternate function <<_strtoul_r>> is a reentrant version.  The
72 extra argument <[reent]> is a pointer to a reentrancy structure.
73 
74 RETURNS
75 <<strtoul>>, <<strtoul_l>> return the converted value, if any. If no
76 conversion was made, <<0>> is returned.
77 
78 <<strtoul>>, <<strtoul_l>> return <<ULONG_MAX>> if the magnitude of the
79 converted value is too large, and sets <<errno>> to <<ERANGE>>.
80 
81 PORTABILITY
82 <<strtoul>> is ANSI.
83 <<strtoul_l>> is a GNU extension.
84 
85 <<strtoul>> requires no supporting OS subroutines.
86 */
87 
88 /*
89  * Copyright (c) 1990 Regents of the University of California.
90  * All rights reserved.
91  *
92  * Redistribution and use in source and binary forms, with or without
93  * modification, are permitted provided that the following conditions
94  * are met:
95  * 1. Redistributions of source code must retain the above copyright
96  *    notice, this list of conditions and the following disclaimer.
97  * 2. Redistributions in binary form must reproduce the above copyright
98  *    notice, this list of conditions and the following disclaimer in the
99  *    documentation and/or other materials provided with the distribution.
100  * 3. All advertising materials mentioning features or use of this software
101  *    must display the following acknowledgement:
102  *	This product includes software developed by the University of
103  *	California, Berkeley and its contributors.
104  * 4. Neither the name of the University nor the names of its contributors
105  *    may be used to endorse or promote products derived from this software
106  *    without specific prior written permission.
107  *
108  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
109  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
110  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
111  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
112  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
113  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
114  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
115  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
116  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
117  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
118  * SUCH DAMAGE.
119  */
120 
121 #define _GNU_SOURCE
122 #include <_ansi.h>
123 #include <limits.h>
124 #include <ctype.h>
125 #include <errno.h>
126 #include <stdlib.h>
127 #include "../locale/setlocale.h"
128 
129 /*
130  * Convert a string to an unsigned long integer.
131  */
132 #ifndef _REENT_ONLY
133 
134 unsigned long
strtoul_l(const char * __restrict nptr,char ** __restrict endptr,int base,locale_t loc)135 strtoul_l (const char *__restrict nptr, char **__restrict endptr, int base,
136 	   locale_t loc)
137 {
138 	register const unsigned char *s = (const unsigned char *)nptr;
139 	register unsigned long acc;
140 	register int c;
141 	register unsigned long cutoff;
142 	register int neg = 0, any, cutlim;
143 
144 	/*
145 	 * See strtol for comments as to the logic used.
146 	 */
147 	do {
148 		c = *s++;
149 	} while (isspace_l(c, loc));
150 	if (c == '-') {
151 		neg = 1;
152 		c = *s++;
153 	} else if (c == '+')
154 		c = *s++;
155 	if ((base == 0 || base == 16) &&
156 	    c == '0' && (*s == 'x' || *s == 'X')) {
157 		c = s[1];
158 		s += 2;
159 		base = 16;
160 	}
161 	if (base == 0)
162 		base = c == '0' ? 8 : 10;
163 	cutoff = (unsigned long)ULONG_MAX / (unsigned long)base;
164 	cutlim = (unsigned long)ULONG_MAX % (unsigned long)base;
165 	for (acc = 0, any = 0;; c = *s++) {
166 		if (c >= '0' && c <= '9')
167 			c -= '0';
168 		else if (c >= 'A' && c <= 'Z')
169 			c -= 'A' - 10;
170 		else if (c >= 'a' && c <= 'z')
171 			c -= 'a' - 10;
172 		else
173 			break;
174 		if (c >= base)
175 			break;
176                if (any < 0 || acc > cutoff || (acc == cutoff && c > cutlim))
177 			any = -1;
178 		else {
179 			any = 1;
180 			acc *= base;
181 			acc += c;
182 		}
183 	}
184 	if (any < 0) {
185 		acc = ULONG_MAX;
186 		__errno_r(rptr) = ERANGE;
187 	} else if (neg)
188 		acc = -acc;
189 	if (endptr != 0)
190 		*endptr = (char *) (any ? (char *)s - 1 : nptr);
191 	return (acc);
192 }
193 
194 unsigned long
strtoul(const char * __restrict s,char ** __restrict ptr,int base)195 strtoul (const char *__restrict s,
196 	char **__restrict ptr,
197 	int base)
198 {
199 	return strtoul_l (s, ptr, base, __get_current_locale ());
200 }
201 
202 #endif
203