blob: bf85e05ce85815a0fb36ab26f9e5642dd455ae1a [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>
Linus Torvalds7c0f6ba2016-12-24 11:46:01 -080020#include <linux/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;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070051
David Howells690d1372012-02-09 15:48:20 +000052 res = 0;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070053 rv = 0;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070054 while (*s) {
55 unsigned int val;
56
57 if ('0' <= *s && *s <= '9')
58 val = *s - '0';
59 else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f')
60 val = _tolower(*s) - 'a' + 10;
Alexey Dobriyan78be9592011-04-14 15:22:02 -070061 else
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070062 break;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070063
64 if (val >= base)
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070065 break;
David Howells690d1372012-02-09 15:48:20 +000066 /*
67 * Check for overflow only if we are within range of
68 * it in the max base we support (16)
69 */
70 if (unlikely(res & (~0ull << 60))) {
71 if (res > div_u64(ULLONG_MAX - val, base))
Alexey Dobriyan8cfd56d2016-10-11 13:51:32 -070072 rv |= KSTRTOX_OVERFLOW;
David Howells690d1372012-02-09 15:48:20 +000073 }
74 res = res * base + val;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070075 rv++;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070076 s++;
77 }
David Howells690d1372012-02-09 15:48:20 +000078 *p = res;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070079 return rv;
80}
81
82static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
83{
84 unsigned long long _res;
85 unsigned int rv;
86
87 s = _parse_integer_fixup_radix(s, &base);
88 rv = _parse_integer(s, base, &_res);
89 if (rv & KSTRTOX_OVERFLOW)
90 return -ERANGE;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070091 if (rv == 0)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070092 return -EINVAL;
Alexey Dobriyan1dff46d2011-10-31 17:12:28 -070093 s += rv;
94 if (*s == '\n')
95 s++;
96 if (*s)
97 return -EINVAL;
98 *res = _res;
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -070099 return 0;
100}
101
Eldad Zack4c925d62012-12-17 16:03:04 -0800102/**
103 * kstrtoull - convert a string to an unsigned long long
104 * @s: The start of the string. The string must be null-terminated, and may also
105 * include a single newline before its terminating null. The first character
106 * may also be a plus sign, but not a minus sign.
107 * @base: The number base to use. The maximum supported base is 16. If base is
108 * given as 0, then the base of the string is automatically detected with the
109 * conventional semantics - If it begins with 0x the number will be parsed as a
110 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
111 * parsed as an octal number. Otherwise it will be parsed as a decimal.
112 * @res: Where to write the result of the conversion on success.
113 *
114 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
115 * Used as a replacement for the obsolete simple_strtoull. Return code must
116 * be checked.
117 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700118int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
119{
120 if (s[0] == '+')
121 s++;
122 return _kstrtoull(s, base, res);
123}
124EXPORT_SYMBOL(kstrtoull);
125
Eldad Zack4c925d62012-12-17 16:03:04 -0800126/**
127 * kstrtoll - convert a string to a long long
128 * @s: The start of the string. The string must be null-terminated, and may also
129 * include a single newline before its terminating null. The first character
130 * may also be a plus sign or a minus sign.
131 * @base: The number base to use. The maximum supported base is 16. If base is
132 * given as 0, then the base of the string is automatically detected with the
133 * conventional semantics - If it begins with 0x the number will be parsed as a
134 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
135 * parsed as an octal number. Otherwise it will be parsed as a decimal.
136 * @res: Where to write the result of the conversion on success.
137 *
138 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
139 * Used as a replacement for the obsolete simple_strtoull. Return code must
140 * be checked.
141 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700142int kstrtoll(const char *s, unsigned int base, long long *res)
143{
144 unsigned long long tmp;
145 int rv;
146
147 if (s[0] == '-') {
148 rv = _kstrtoull(s + 1, base, &tmp);
149 if (rv < 0)
150 return rv;
Alexey Dobriyan2d2e4712015-09-09 15:36:17 -0700151 if ((long long)-tmp > 0)
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700152 return -ERANGE;
153 *res = -tmp;
154 } else {
155 rv = kstrtoull(s, base, &tmp);
156 if (rv < 0)
157 return rv;
158 if ((long long)tmp < 0)
159 return -ERANGE;
160 *res = tmp;
161 }
162 return 0;
163}
164EXPORT_SYMBOL(kstrtoll);
165
166/* Internal, do not use. */
167int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
168{
169 unsigned long long tmp;
170 int rv;
171
172 rv = kstrtoull(s, base, &tmp);
173 if (rv < 0)
174 return rv;
175 if (tmp != (unsigned long long)(unsigned long)tmp)
176 return -ERANGE;
177 *res = tmp;
178 return 0;
179}
180EXPORT_SYMBOL(_kstrtoul);
181
182/* Internal, do not use. */
183int _kstrtol(const char *s, unsigned int base, long *res)
184{
185 long long tmp;
186 int rv;
187
188 rv = kstrtoll(s, base, &tmp);
189 if (rv < 0)
190 return rv;
191 if (tmp != (long long)(long)tmp)
192 return -ERANGE;
193 *res = tmp;
194 return 0;
195}
196EXPORT_SYMBOL(_kstrtol);
197
Eldad Zack4c925d62012-12-17 16:03:04 -0800198/**
199 * kstrtouint - convert a string to an unsigned int
200 * @s: The start of the string. The string must be null-terminated, and may also
201 * include a single newline before its terminating null. The first character
202 * may also be a plus sign, but not a minus sign.
203 * @base: The number base to use. The maximum supported base is 16. If base is
204 * given as 0, then the base of the string is automatically detected with the
205 * conventional semantics - If it begins with 0x the number will be parsed as a
206 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
207 * parsed as an octal number. Otherwise it will be parsed as a decimal.
208 * @res: Where to write the result of the conversion on success.
209 *
210 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
211 * Used as a replacement for the obsolete simple_strtoull. Return code must
212 * be checked.
213 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700214int kstrtouint(const char *s, unsigned int base, unsigned int *res)
215{
216 unsigned long long tmp;
217 int rv;
218
219 rv = kstrtoull(s, base, &tmp);
220 if (rv < 0)
221 return rv;
222 if (tmp != (unsigned long long)(unsigned int)tmp)
223 return -ERANGE;
224 *res = tmp;
225 return 0;
226}
227EXPORT_SYMBOL(kstrtouint);
228
Eldad Zack4c925d62012-12-17 16:03:04 -0800229/**
230 * kstrtoint - convert a string to an int
231 * @s: The start of the string. The string must be null-terminated, and may also
232 * include a single newline before its terminating null. The first character
233 * may also be a plus sign or a minus sign.
234 * @base: The number base to use. The maximum supported base is 16. If base is
235 * given as 0, then the base of the string is automatically detected with the
236 * conventional semantics - If it begins with 0x the number will be parsed as a
237 * hexadecimal (case insensitive), if it otherwise begins with 0, it will be
238 * parsed as an octal number. Otherwise it will be parsed as a decimal.
239 * @res: Where to write the result of the conversion on success.
240 *
241 * Returns 0 on success, -ERANGE on overflow and -EINVAL on parsing error.
242 * Used as a replacement for the obsolete simple_strtoull. Return code must
243 * be checked.
244 */
Alexey Dobriyan33ee3b22011-03-22 16:34:40 -0700245int kstrtoint(const char *s, unsigned int base, int *res)
246{
247 long long tmp;
248 int rv;
249
250 rv = kstrtoll(s, base, &tmp);
251 if (rv < 0)
252 return rv;
253 if (tmp != (long long)(int)tmp)
254 return -ERANGE;
255 *res = tmp;
256 return 0;
257}
258EXPORT_SYMBOL(kstrtoint);
259
260int kstrtou16(const char *s, unsigned int base, u16 *res)
261{
262 unsigned long long tmp;
263 int rv;
264
265 rv = kstrtoull(s, base, &tmp);
266 if (rv < 0)
267 return rv;
268 if (tmp != (unsigned long long)(u16)tmp)
269 return -ERANGE;
270 *res = tmp;
271 return 0;
272}
273EXPORT_SYMBOL(kstrtou16);
274
275int kstrtos16(const char *s, unsigned int base, s16 *res)
276{
277 long long tmp;
278 int rv;
279
280 rv = kstrtoll(s, base, &tmp);
281 if (rv < 0)
282 return rv;
283 if (tmp != (long long)(s16)tmp)
284 return -ERANGE;
285 *res = tmp;
286 return 0;
287}
288EXPORT_SYMBOL(kstrtos16);
289
290int kstrtou8(const char *s, unsigned int base, u8 *res)
291{
292 unsigned long long tmp;
293 int rv;
294
295 rv = kstrtoull(s, base, &tmp);
296 if (rv < 0)
297 return rv;
298 if (tmp != (unsigned long long)(u8)tmp)
299 return -ERANGE;
300 *res = tmp;
301 return 0;
302}
303EXPORT_SYMBOL(kstrtou8);
304
305int kstrtos8(const char *s, unsigned int base, s8 *res)
306{
307 long long tmp;
308 int rv;
309
310 rv = kstrtoll(s, base, &tmp);
311 if (rv < 0)
312 return rv;
313 if (tmp != (long long)(s8)tmp)
314 return -ERANGE;
315 *res = tmp;
316 return 0;
317}
318EXPORT_SYMBOL(kstrtos8);
Alexey Dobriyanc196e322011-05-24 17:13:31 -0700319
Kees Cookef951592016-03-17 14:22:50 -0700320/**
321 * kstrtobool - convert common user inputs into boolean values
322 * @s: input string
323 * @res: result
324 *
Kees Cooka81a5a12016-03-17 14:22:57 -0700325 * This routine returns 0 iff the first character is one of 'Yy1Nn0', or
326 * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL. Value
327 * pointed to by res is updated upon finding a match.
Kees Cookef951592016-03-17 14:22:50 -0700328 */
329int kstrtobool(const char *s, bool *res)
330{
331 if (!s)
332 return -EINVAL;
333
334 switch (s[0]) {
335 case 'y':
336 case 'Y':
337 case '1':
338 *res = true;
339 return 0;
340 case 'n':
341 case 'N':
342 case '0':
343 *res = false;
344 return 0;
Kees Cooka81a5a12016-03-17 14:22:57 -0700345 case 'o':
346 case 'O':
347 switch (s[1]) {
348 case 'n':
349 case 'N':
350 *res = true;
351 return 0;
352 case 'f':
353 case 'F':
354 *res = false;
355 return 0;
356 default:
357 break;
358 }
Kees Cookef951592016-03-17 14:22:50 -0700359 default:
360 break;
361 }
362
363 return -EINVAL;
364}
365EXPORT_SYMBOL(kstrtobool);
366
367/*
368 * Since "base" would be a nonsense argument, this open-codes the
369 * _from_user helper instead of using the helper macro below.
370 */
371int kstrtobool_from_user(const char __user *s, size_t count, bool *res)
372{
373 /* Longest string needed to differentiate, newline, terminator */
374 char buf[4];
375
376 count = min(count, sizeof(buf) - 1);
377 if (copy_from_user(buf, s, count))
378 return -EFAULT;
379 buf[count] = '\0';
380 return kstrtobool(buf, res);
381}
382EXPORT_SYMBOL(kstrtobool_from_user);
383
Alexey Dobriyanc196e322011-05-24 17:13:31 -0700384#define kstrto_from_user(f, g, type) \
385int f(const char __user *s, size_t count, unsigned int base, type *res) \
386{ \
387 /* sign, base 2 representation, newline, terminator */ \
388 char buf[1 + sizeof(type) * 8 + 1 + 1]; \
389 \
390 count = min(count, sizeof(buf) - 1); \
391 if (copy_from_user(buf, s, count)) \
392 return -EFAULT; \
393 buf[count] = '\0'; \
394 return g(buf, base, res); \
395} \
396EXPORT_SYMBOL(f)
397
398kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long);
399kstrto_from_user(kstrtoll_from_user, kstrtoll, long long);
400kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long);
401kstrto_from_user(kstrtol_from_user, kstrtol, long);
402kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int);
403kstrto_from_user(kstrtoint_from_user, kstrtoint, int);
404kstrto_from_user(kstrtou16_from_user, kstrtou16, u16);
405kstrto_from_user(kstrtos16_from_user, kstrtos16, s16);
406kstrto_from_user(kstrtou8_from_user, kstrtou8, u8);
407kstrto_from_user(kstrtos8_from_user, kstrtos8, s8);