aboutsummaryrefslogtreecommitdiffstats
path: root/lib/kstrtox.c
blob: 05672e819f8c4c9164dd40e3752d23b8b5f63577 (plain) (blame)
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
224
225
226
227
/*
 * Convert integer string representation to an integer.
 * If an integer doesn't fit into specified type, -E is returned.
 *
 * Integer starts with optional sign.
 * kstrtou*() functions do not accept sign "-".
 *
 * Radix 0 means autodetection: leading "0x" implies radix 16,
 * leading "0" implies radix 8, otherwise radix is 10.
 * Autodetection hints work after optional sign, but not before.
 *
 * If -E is returned, result is not touched.
 */
#include <linux/ctype.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/math64.h>
#include <linux/module.h>
#include <linux/types.h>

static inline char _tolower(const char c)
{
	return c | 0x20;
}

static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
{
	unsigned long long acc;
	int ok;

	if (base == 0) {
		if (s[0] == '0') {
			if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
				base = 16;
			else
				base = 8;
		} else
			base = 10;
	}
	if (base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
		s += 2;

	acc = 0;
	ok = 0;
	while (*s) {
		unsigned int val;

		if ('0' <= *s && *s <= '9')
			val = *s - '0';
		else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f')
			val = _tolower(*s) - 'a' + 10;
		else if (*s == '\n') {
			if (*(s + 1) == '\0')
				break;
			else
				return -EINVAL;
		} else
			return -EINVAL;

		if (val >= base)
			return -EINVAL;
		if (acc > div_u64(ULLONG_MAX - val, base))
			return -ERANGE;
		acc = acc * base + val;
		ok = 1;

		s++;
	}
	if (!ok)
		return -EINVAL;
	*res = acc;
	return 0;
}

int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
{
	if (s[0] == '+')
		s++;
	return _kstrtoull(s, base, res);
}
EXPORT_SYMBOL(kstrtoull);

int kstrtoll(const char *s, unsigned int base, long long *res)
{
	unsigned long long tmp;
	int rv;

	if (s[0] == '-') {
		rv = _kstrtoull(s + 1, base, &tmp);
		if (rv < 0)
			return rv;
		if ((long long)(-tmp) >= 0)
			return -ERANGE;
		*res = -tmp;
	} else {
		rv = kstrtoull(s, base, &tmp);
		if (rv < 0)
			return rv;
		if ((long long)tmp < 0)
			return -ERANGE;
		*res = tmp;
	}
	return 0;
}
EXPORT_SYMBOL(kstrtoll);

/* Internal, do not use. */
int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (unsigned long long)(unsigned long)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(_kstrtoul);

/* Internal, do not use. */
int _kstrtol(const char *s, unsigned int base, long *res)
{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (long long)(long)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(_kstrtol);

int kstrtouint(const char *s, unsigned int base, unsigned int *res)
{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (unsigned long long)(unsigned int)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(kstrtouint);

int kstrtoint(const char *s, unsigned int base, int *res)
{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (long long)(int)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(kstrtoint);

int kstrtou16(const char *s, unsigned int base, u16 *res)
{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (unsigned long long)(u16)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(kstrtou16);

int kstrtos16(const char *s, unsigned int base, s16 *res)
{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (long long)(s16)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(kstrtos16);

int kstrtou8(const char *s, unsigned int base, u8 *res)
{
	unsigned long long tmp;
	int rv;

	rv = kstrtoull(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (unsigned long long)(u8)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(kstrtou8);

int kstrtos8(const char *s, unsigned int base, s8 *res)
{
	long long tmp;
	int rv;

	rv = kstrtoll(s, base, &tmp);
	if (rv < 0)
		return rv;
	if (tmp != (long long)(s8)tmp)
		return -ERANGE;
	*res = tmp;
	return 0;
}
EXPORT_SYMBOL(kstrtos8);