1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
/*
* Very simple implementation of strtoul() for gawk,
* for old systems. Descriptive prose from the Linux man page.
*
* May 2004
*/
/* #define TEST 1 */
#ifdef TEST
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <errno.h>
#include <limits.h>
#define TRUE 1
#define FALSE 0
#define strtoul mystrtoul
#endif
#ifndef ULONG_MAX
#define ULONG_MAX (~ 0UL)
#endif
unsigned long int
strtoul(nptr, endptr, base)
const char *nptr;
char **endptr;
int base;
{
static char lower[] = "abcdefghijklmnopqrstuvwxyz";
unsigned long result = 0UL;
char *nptr_orig = (char *) nptr;
int neg = FALSE;
char *cp, c;
int val;
int sawdigs = FALSE;
/*
* The strtoul() function converts the initial part of the
* string in nptr to an unsigned long integer value according
* to the given base, which must be between 2 and 36 inclusive,
* or be the special value 0.
*/
if ((base != 0 && (base < 2 || base > 36)) || nptr == NULL) {
if (endptr != NULL)
*endptr = nptr_orig;
errno = EINVAL;
return 0;
}
/*
* The string must [sic] begin with an arbitrary amount of white space
* (as determined by isspace(3)) followed by a single optional
* `+' or `-' sign.
*/
while (isspace(*nptr))
nptr++;
if (*nptr == '+')
nptr++;
else if (*nptr == '-') {
nptr++;
neg = TRUE;
}
/*
* If base is zero or 16, the string may then include a `0x' prefix,
* and the number will be read in base 16; otherwise, a zero base is
* taken as 10 (decimal) unless the next character is `0', in which
* case it is taken as 8 (octal).
*/
if ((base == 0 || base == 16)
&& nptr[0] == '0'
&& (nptr[1] == 'x' || nptr[1] == 'X')) {
base = 16; /* force it */
nptr += 2; /* skip 0x */
} else if ((base == 0 || base == 8) && nptr[0] == '0') {
base = 8;
nptr++;
} else if (base == 0)
base = 10;
/*
* The remainder of the string is converted to an unsigned long int
* value in the obvious manner, stopping at the first character
* which is not a valid digit in the given base. (In bases above 10,
* the letter `A' in either upper or lower case represents 10,
* `B' represents 11, and so forth, with `Z' representing 35.)
*/
for (; *nptr != '\0'; nptr++) {
c = *nptr;
#if defined(HAVE_LOCALE_H)
if (base == 10
&& loc.thousands_sep != NULL
&& loc.thousands_sep[0] != '\0'
&& c == loc.thousands_sep[0])
continue;
#endif
switch (c) {
case '0': case '1': case '2':
case '3': case '4': case '5':
case '6': case '7': case '8':
case '9':
val = c - '0';
if (val >= base) /* even base 2 allowed ... */
goto out;
result *= base;
result += val;
sawdigs = TRUE;
break;
case 'A': case 'B': case 'C': case 'D': case 'E':
case 'F': case 'G': case 'H': case 'I': case 'J':
case 'K': case 'L': case 'M': case 'N': case 'O':
case 'P': case 'Q': case 'R': case 'S': case 'T':
case 'U': case 'V': case 'W': case 'X': case 'Y':
case 'Z':
c += 'a' - 'A'; /* downcase */
/* fall through */
case 'a': case 'b': case 'c': case 'd': case 'e':
case 'f': case 'g': case 'h': case 'i': case 'j':
case 'k': case 'l': case 'm': case 'n': case 'o':
case 'p': case 'q': case 'r': case 's': case 't':
case 'u': case 'v': case 'w': case 'x': case 'y':
case 'z':
cp = strchr(lower, c);
val = cp - lower;
val += 10; /* 'a' == 10 */
if (val >= base)
goto out;
result *= base;
result += val;
sawdigs = TRUE;
break;
default:
goto out;
}
}
out:
/*
* If endptr is not NULL, strtoul() stores the address of the
* first invalid character in *endptr. If there were no digits
* at all, strtoul() stores the original value of nptr in *endptr
* (and returns 0). In particular, if *nptr is not `\0' but
* **endptr is `\0' on return, the entire string is valid.
*/
if (endptr != NULL) {
if (! sawdigs) {
*endptr = nptr_orig;
return 0;
} else
*endptr = (char *) nptr;
}
/*
* RETURN VALUE
* The strtoul() function returns either the result of the
* conversion or, if there was a leading minus sign, the
* negation of the result of the conversion, unless the original
* (non-negated) value would overflow; in the latter case,
* strtoul() returns ULONG_MAX and sets the global variable errno
* to ERANGE.
*/
/*
* ADR: This computation is probably bogus. If it's a
* problem, upgrade to a modern system.
*/
if (neg && result == ULONG_MAX) {
errno = ERANGE;
return ULONG_MAX;
} else if (neg)
result = -result;
return result;
}
#ifdef TEST
#undef strtoul
int main(void)
{
char *endptr;
unsigned long res1, res2;
res1 = strtoul("0xdeadBeeF", & endptr, 0),
res2 = mystrtoul("0xdeadBeeF", & endptr, 0),
printf("(real,my)strtoul(\"0xdeadBeeF\", & endptr, 0) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("0101101", & endptr, 2),
res2 = mystrtoul("0101101", & endptr, 2),
printf("(real,my)strtoul(\"0101101\", & endptr, 2) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("01011012", & endptr, 2),
res2 = mystrtoul("01011012", & endptr, 2),
printf("(real,my)strtoul(\"01011012\", & endptr, 2) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul(" +42a", & endptr, 0),
res2 = mystrtoul(" +42a", & endptr, 0),
printf("(real,my)strtoul(\" +42a\", & endptr, 0) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("0377", & endptr, 0),
res2 = mystrtoul("0377", & endptr, 0),
printf("(real,my)strtoul(\"0377\", & endptr, 0) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("Z", & endptr, 36),
res2 = mystrtoul("Z", & endptr, 36),
printf("(real,my)strtoul(\"Z\", & endptr, 36) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
res1 = strtoul("qZ*", & endptr, 36),
res2 = mystrtoul("qZ*", & endptr, 36),
printf("(real,my)strtoul(\"qZ*\", & endptr, 36) is %lu, %lu *endptr = %d\n",
res1, res2, *endptr);
}
#endif
|
