Annotation of prex-old/usr/lib/libc/stdlib/strtoul.c, Revision 1.1.1.1
1.1 nbrk 1: /*
2: * Copyright (c) 1990, 1993
3: * The Regents of the University of California. All rights reserved.
4: *
5: * Redistribution and use in source and binary forms, with or without
6: * modification, are permitted provided that the following conditions
7: * are met:
8: * 1. Redistributions of source code must retain the above copyright
9: * notice, this list of conditions and the following disclaimer.
10: * 2. Redistributions in binary form must reproduce the above copyright
11: * notice, this list of conditions and the following disclaimer in the
12: * documentation and/or other materials provided with the distribution.
13: * 3. Neither the name of the University nor the names of its contributors
14: * may be used to endorse or promote products derived from this software
15: * without specific prior written permission.
16: *
17: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27: * SUCH DAMAGE.
28: */
29:
30: #include <limits.h>
31: #include <ctype.h>
32: #include <errno.h>
33: #include <stdlib.h>
34:
35: /*
36: * Convert a string to an unsigned long integer.
37: *
38: * Ignores `locale' stuff. Assumes that the upper and lower case
39: * alphabets and digits are each contiguous.
40: */
41: unsigned long
42: strtoul(nptr, endptr, base)
43: const char *nptr;
44: char **endptr;
45: register int base;
46: {
47: const char *s;
48: unsigned long acc, cutoff;
49: int c;
50: int neg, any, cutlim;
51:
52: /*
53: * See strtol for comments as to the logic used.
54: */
55: s = nptr;
56: do {
57: c = (unsigned char) *s++;
58: } while (isspace(c));
59: if (c == '-') {
60: neg = 1;
61: c = *s++;
62: } else {
63: neg = 0;
64: if (c == '+')
65: c = *s++;
66: }
67: if ((base == 0 || base == 16) &&
68: c == '0' && (*s == 'x' || *s == 'X')) {
69: c = s[1];
70: s += 2;
71: base = 16;
72: }
73: if (base == 0)
74: base = c == '0' ? 8 : 10;
75:
76: cutoff = ULONG_MAX / (unsigned long)base;
77: cutlim = (int)(ULONG_MAX % (unsigned long)base);
78: for (acc = 0, any = 0;; c = (unsigned char) *s++) {
79: if (isdigit(c))
80: c -= '0';
81: else if (isalpha(c))
82: c -= isupper(c) ? 'A' - 10 : 'a' - 10;
83: else
84: break;
85: if (c >= base)
86: break;
87: if (any < 0)
88: continue;
89: if (acc > cutoff || (acc == cutoff && c > cutlim)) {
90: any = -1;
91: acc = ULONG_MAX;
92: errno = ERANGE;
93: } else {
94: any = 1;
95: acc *= (unsigned long)base;
96: acc += c;
97: }
98: }
99: if (neg && any > 0)
100: acc = -acc;
101: if (endptr != 0)
102: /* LINTED interface specification */
103: *endptr = (char *)(any ? s - 1 : nptr);
104: return (acc);
105: }
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