1 /* Copyright (C) 1989, 1990, 1991, 1992 Free Software Foundation, Inc.
2 Written by James Clark (jjc@jclark.com)
3
4 This file is part of groff.
5
6 groff is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 2, or (at your option) any later
9 version.
10
11 groff is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License along
17 with groff; see the file COPYING. If not, write to the Free Software
18 Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
19
20 #include <string.h>
21 #include <ctype.h>
22 #include <errno.h>
23 #ifndef errno
24 extern int errno;
25 #endif
26
27 #ifdef HAVE_LIMITS_H
28 #include <limits.h>
29 #endif
30
31 #ifndef LONG_MAX
32 #define LONG_MAX 2147483647
33 #endif
34
35 #ifndef LONG_MIN
36 #define LONG_MIN (-LONG_MAX-1)
37 #endif
38
strtol(str,ptr,base)39 long strtol(str, ptr, base)
40 char *str, **ptr;
41 int base;
42 {
43 char *start = str;
44 int neg = 0;
45 long val;
46 char *p;
47 static char digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
48
49 while (isascii(*str) && isspace(*str))
50 str++;
51
52 if (*str == '-') {
53 neg = 1;
54 str++;
55 }
56 if (base == 0) {
57 if (*str == '0') {
58 if (str[1] == 'x' || str[1] == 'X') {
59 str += 2;
60 base = 16;
61 }
62 else
63 base = 8;
64 }
65 else
66 base = 10;
67 }
68 if (base < 2 || base > 36)
69 base = 10;
70 else if (base == 16 && *str == '0' && (str[1] == 'x' || str[1] == 'X'))
71 str += 2;
72
73 p = strchr(digits, isascii(*str) && isupper(*str) ? tolower(*str) : *str);
74 if (p == 0 || (val = (p - digits)) >= base) {
75 if (base == 16 && str > start && (str[-1] == 'x' || str[-1] == 'X')) {
76 if (ptr)
77 *ptr = str - 1;
78 }
79 else {
80 if (ptr)
81 *ptr = start;
82 errno = ERANGE;
83 }
84 return 0;
85 }
86 if (neg)
87 val = -val;
88
89 while (*++str != '\0') {
90 int n;
91
92 p = strchr(digits, isascii(*str) && isupper(*str) ? tolower(*str) : *str);
93 if (p == 0)
94 break;
95 n = p - digits;
96 if (n >= base)
97 break;
98 if (neg) {
99 if (-(unsigned long)val > (-(unsigned long)LONG_MIN - n)/base) {
100 val = LONG_MIN;
101 errno = ERANGE;
102 }
103 else
104 val = val*base - n;
105 }
106 else {
107 if (val > (LONG_MAX - n)/base) {
108 val = LONG_MAX;
109 errno = ERANGE;
110 }
111 else
112 val = val*base + n;
113 }
114 }
115
116 if (ptr)
117 *ptr = str;
118
119 return val;
120 }
121