blob: e8ba4a013e82f558565da40fba86473ce5e1a091 [file] [log] [blame]
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -07001/*
2 * Convert integer string representation to an integer.
3 * If an integer doesn't fit into specified type, -E is returned.
4 *
5 * Integer starts with optional sign.
6 * kstrtou*() functions do not accept sign "-".
7 *
8 * Radix 0 means autodetection: leading "0x" implies radix 16,
9 * leading "0" implies radix 8, otherwise radix is 10.
10 * Autodetection hints work after optional sign, but not before.
11 *
12 * If -E is returned, result is not touched.
13 */
14#include <linux/ctype.h>
15#include <linux/errno.h>
16#include <linux/kernel.h>
17#include <linux/math64.h>
Paul Gortmaker8bc3bcc2011-11-16 21:29:17 -050018#include <linux/export.h>
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070019#include <linux/types.h>
Alexey Dobriyanc196e322011-05-24 17:13:31 -070020#include <asm/uaccess.h>
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070021#include "kstrtox.h"
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070022
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070023const char *_parse_integer_fixup_radix(const char *s, unsigned int *base)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070024{
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070025 if (*base == 0) {
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070026 if (s[0] == '0') {
27 if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070028 *base = 16;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070029 else
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070030 *base = 8;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070031 } else
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070032 *base = 10;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070033 }
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070034 if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070035 s += 2;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070036 return s;
37}
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070038
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070039/*
40 * Convert non-negative integer string representation in explicitly given radix
41 * to an integer.
42 * Return number of characters consumed maybe or-ed with overflow bit.
43 * If overflow occurs, result integer (incorrect) is still returned.
44 *
45 * Don't you dare use this function.
46 */
David Howells690d1372012-02-09 15:48:20 +000047unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p)
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070048{
David Howells690d1372012-02-09 15:48:20 +000049 unsigned long long res;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070050 unsigned int rv;
51 int overflow;
52
David Howells690d1372012-02-09 15:48:20 +000053 res = 0;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070054 rv = 0;
55 overflow = 0;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070056 while (*s) {
57 unsigned int val;
58
59 if ('0' <= *s && *s <= '9')
60 val = *s - '0';
61 else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f')
62 val = _tolower(*s) - 'a' + 10;
Alexey Dobriyan78be9592011-04-14 15:22:02 -070063 else
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070064 break;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070065
66 if (val >= base)
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070067 break;
David Howells690d1372012-02-09 15:48:20 +000068 /*
69 * Check for overflow only if we are within range of
70 * it in the max base we support (16)
71 */
72 if (unlikely(res & (~0ull << 60))) {
73 if (res > div_u64(ULLONG_MAX - val, base))
74 overflow = 1;
75 }
76 res = res * base + val;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070077 rv++;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070078 s++;
79 }
David Howells690d1372012-02-09 15:48:20 +000080 *p = res;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070081 if (overflow)
82 rv |= KSTRTOX_OVERFLOW;
83 return rv;
84}
85
86static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
87{
88 unsigned long long _res;
89 unsigned int rv;
90
91 s = _parse_integer_fixup_radix(s, &base);
92 rv = _parse_integer(s, base, &_res);
93 if (rv & KSTRTOX_OVERFLOW)
94 return -ERANGE;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070095 if (rv == 0)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070096 return -EINVAL;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070097 s += rv;
98 if (*s == '\n')
99 s++;
100 if (*s)
101 return -EINVAL;
102 *res = _res;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700103 return 0;
104}
105
Eldad Zack4c925d62012-12-17 16:03:04 -0800106/**
107 * kstrtoull - convert a string to an unsigned long long
108 * @s: The start of the string. The string must be null-terminated, and may also
109 * include a single newline before its terminating null. The first character
110 * may also be a plus sign, but not a minus sign.
111 * @base: The number base to use. The maximum supported base is 16. If base is
112 * given as 0, then the base of the string is automatically detected with the
113 * conventional semantics - If it begins with 0x the number will be parsed as a
114 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
115 * parsed as an octal number. Otherwise it will be parsed as a decimal.
116 * @res: Where to write the result of the conversion on success.
117 *
118 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
119 * Used as a replacement for the obsolete simple_strtoull. Return code must
120 * be checked.
121 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700122int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
123{
124 if (s[0] == '+')
125 s++;
126 return _kstrtoull(s, base, res);
127}
128EXPORT_SYMBOL(kstrtoull);
129
Eldad Zack4c925d62012-12-17 16:03:04 -0800130/**
131 * kstrtoll - convert a string to a long long
132 * @s: The start of the string. The string must be null-terminated, and may also
133 * include a single newline before its terminating null. The first character
134 * may also be a plus sign or a minus sign.
135 * @base: The number base to use. The maximum supported base is 16. If base is
136 * given as 0, then the base of the string is automatically detected with the
137 * conventional semantics - If it begins with 0x the number will be parsed as a
138 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
139 * parsed as an octal number. Otherwise it will be parsed as a decimal.
140 * @res: Where to write the result of the conversion on success.
141 *
142 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
143 * Used as a replacement for the obsolete simple_strtoull. Return code must
144 * be checked.
145 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700146int kstrtoll(const char *s, unsigned int base, long long *res)
147{
148 unsigned long long tmp;
149 int rv;
150
151 if (s[0] == '-') {
152 rv = _kstrtoull(s + 1, base, &tmp);
153 if (rv < 0)
154 return rv;
Alexey Dobriyan2d2e4712015-09-09 15:36:17 -0700155 if ((long long)-tmp > 0)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700156 return -ERANGE;
157 *res = -tmp;
158 } else {
159 rv = kstrtoull(s, base, &tmp);
160 if (rv < 0)
161 return rv;
162 if ((long long)tmp < 0)
163 return -ERANGE;
164 *res = tmp;
165 }
166 return 0;
167}
168EXPORT_SYMBOL(kstrtoll);
169
170/* Internal, do not use. */
171int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
172{
173 unsigned long long tmp;
174 int rv;
175
176 rv = kstrtoull(s, base, &tmp);
177 if (rv < 0)
178 return rv;
179 if (tmp != (unsigned long long)(unsigned long)tmp)
180 return -ERANGE;
181 *res = tmp;
182 return 0;
183}
184EXPORT_SYMBOL(_kstrtoul);
185
186/* Internal, do not use. */
187int _kstrtol(const char *s, unsigned int base, long *res)
188{
189 long long tmp;
190 int rv;
191
192 rv = kstrtoll(s, base, &tmp);
193 if (rv < 0)
194 return rv;
195 if (tmp != (long long)(long)tmp)
196 return -ERANGE;
197 *res = tmp;
198 return 0;
199}
200EXPORT_SYMBOL(_kstrtol);
201
Eldad Zack4c925d62012-12-17 16:03:04 -0800202/**
203 * kstrtouint - convert a string to an unsigned int
204 * @s: The start of the string. The string must be null-terminated, and may also
205 * include a single newline before its terminating null. The first character
206 * may also be a plus sign, but not a minus sign.
207 * @base: The number base to use. The maximum supported base is 16. If base is
208 * given as 0, then the base of the string is automatically detected with the
209 * conventional semantics - If it begins with 0x the number will be parsed as a
210 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
211 * parsed as an octal number. Otherwise it will be parsed as a decimal.
212 * @res: Where to write the result of the conversion on success.
213 *
214 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
215 * Used as a replacement for the obsolete simple_strtoull. Return code must
216 * be checked.
217 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700218int kstrtouint(const char *s, unsigned int base, unsigned int *res)
219{
220 unsigned long long tmp;
221 int rv;
222
223 rv = kstrtoull(s, base, &tmp);
224 if (rv < 0)
225 return rv;
226 if (tmp != (unsigned long long)(unsigned int)tmp)
227 return -ERANGE;
228 *res = tmp;
229 return 0;
230}
231EXPORT_SYMBOL(kstrtouint);
232
Eldad Zack4c925d62012-12-17 16:03:04 -0800233/**
234 * kstrtoint - convert a string to an int
235 * @s: The start of the string. The string must be null-terminated, and may also
236 * include a single newline before its terminating null. The first character
237 * may also be a plus sign or a minus sign.
238 * @base: The number base to use. The maximum supported base is 16. If base is
239 * given as 0, then the base of the string is automatically detected with the
240 * conventional semantics - If it begins with 0x the number will be parsed as a
241 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
242 * parsed as an octal number. Otherwise it will be parsed as a decimal.
243 * @res: Where to write the result of the conversion on success.
244 *
245 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
246 * Used as a replacement for the obsolete simple_strtoull. Return code must
247 * be checked.
248 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700249int kstrtoint(const char *s, unsigned int base, int *res)
250{
251 long long tmp;
252 int rv;
253
254 rv = kstrtoll(s, base, &tmp);
255 if (rv < 0)
256 return rv;
257 if (tmp != (long long)(int)tmp)
258 return -ERANGE;
259 *res = tmp;
260 return 0;
261}
262EXPORT_SYMBOL(kstrtoint);
263
264int kstrtou16(const char *s, unsigned int base, u16 *res)
265{
266 unsigned long long tmp;
267 int rv;
268
269 rv = kstrtoull(s, base, &tmp);
270 if (rv < 0)
271 return rv;
272 if (tmp != (unsigned long long)(u16)tmp)
273 return -ERANGE;
274 *res = tmp;
275 return 0;
276}
277EXPORT_SYMBOL(kstrtou16);
278
279int kstrtos16(const char *s, unsigned int base, s16 *res)
280{
281 long long tmp;
282 int rv;
283
284 rv = kstrtoll(s, base, &tmp);
285 if (rv < 0)
286 return rv;
287 if (tmp != (long long)(s16)tmp)
288 return -ERANGE;
289 *res = tmp;
290 return 0;
291}
292EXPORT_SYMBOL(kstrtos16);
293
294int kstrtou8(const char *s, unsigned int base, u8 *res)
295{
296 unsigned long long tmp;
297 int rv;
298
299 rv = kstrtoull(s, base, &tmp);
300 if (rv < 0)
301 return rv;
302 if (tmp != (unsigned long long)(u8)tmp)
303 return -ERANGE;
304 *res = tmp;
305 return 0;
306}
307EXPORT_SYMBOL(kstrtou8);
308
309int kstrtos8(const char *s, unsigned int base, s8 *res)
310{
311 long long tmp;
312 int rv;
313
314 rv = kstrtoll(s, base, &tmp);
315 if (rv < 0)
316 return rv;
317 if (tmp != (long long)(s8)tmp)
318 return -ERANGE;
319 *res = tmp;
320 return 0;
321}
322EXPORT_SYMBOL(kstrtos8);
Alexey Dobriyanc196e322011-05-24 17:13:31 -0700323
Kees Cookef951592016-03-17 14:22:50 -0700324/**
325 * kstrtobool - convert common user inputs into boolean values
326 * @s: input string
327 * @res: result
328 *
329 * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
330 * Otherwise it will return -EINVAL. Value pointed to by res is
331 * updated upon finding a match.
332 */
333int kstrtobool(const char *s, bool *res)
334{
335 if (!s)
336 return -EINVAL;
337
338 switch (s[0]) {
339 case 'y':
340 case 'Y':
341 case '1':
342 *res = true;
343 return 0;
344 case 'n':
345 case 'N':
346 case '0':
347 *res = false;
348 return 0;
349 default:
350 break;
351 }
352
353 return -EINVAL;
354}
355EXPORT_SYMBOL(kstrtobool);
356
357/*
358 * Since "base" would be a nonsense argument, this open-codes the
359 * _from_user helper instead of using the helper macro below.
360 */
361int kstrtobool_from_user(const char __user *s, size_t count, bool *res)
362{
363 /* Longest string needed to differentiate, newline, terminator */
364 char buf[4];
365
366 count = min(count, sizeof(buf) - 1);
367 if (copy_from_user(buf, s, count))
368 return -EFAULT;
369 buf[count] = '\0';
370 return kstrtobool(buf, res);
371}
372EXPORT_SYMBOL(kstrtobool_from_user);
373
Alexey Dobriyanc196e322011-05-24 17:13:31 -0700374#define kstrto_from_user(f, g, type) \
375int f(const char __user *s, size_t count, unsigned int base, type *res) \
376{ \
377 /* sign, base 2 representation, newline, terminator */ \
378 char buf[1 + sizeof(type) * 8 + 1 + 1]; \
379 \
380 count = min(count, sizeof(buf) - 1); \
381 if (copy_from_user(buf, s, count)) \
382 return -EFAULT; \
383 buf[count] = '\0'; \
384 return g(buf, base, res); \
385} \
386EXPORT_SYMBOL(f)
387
388kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long);
389kstrto_from_user(kstrtoll_from_user, kstrtoll, long long);
390kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long);
391kstrto_from_user(kstrtol_from_user, kstrtol, long);
392kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int);
393kstrto_from_user(kstrtoint_from_user, kstrtoint, int);
394kstrto_from_user(kstrtou16_from_user, kstrtou16, u16);
395kstrto_from_user(kstrtos16_from_user, kstrtos16, s16);
396kstrto_from_user(kstrtou8_from_user, kstrtou8, u8);
397kstrto_from_user(kstrtos8_from_user, kstrtos8, s8);