2 * Convert integer string representation to an integer.
3 * If an integer doesn't fit into specified type, -E is returned.
5 * Integer starts with optional sign.
6 * kstrtou*() functions do not accept sign "-".
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.
12 * If -E is returned, result is not touched.
14 #include <linux/ctype.h>
15 #include <linux/errno.h>
16 #include <linux/kernel.h>
17 #include <linux/math64.h>
18 #include <linux/export.h>
19 #include <linux/types.h>
20 #include <asm/uaccess.h>
23 const char *_parse_integer_fixup_radix(const char *s, unsigned int *base)
27 if (_tolower(s[1]) == 'x' && isxdigit(s[2]))
34 if (*base == 16 && s[0] == '0' && _tolower(s[1]) == 'x')
40 * Convert non-negative integer string representation in explicitly given radix
42 * Return number of characters consumed maybe or-ed with overflow bit.
43 * If overflow occurs, result integer (incorrect) is still returned.
45 * Don't you dare use this function.
47 unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long *p)
49 unsigned long long res;
59 if ('0' <= *s && *s <= '9')
61 else if ('a' <= _tolower(*s) && _tolower(*s) <= 'f')
62 val = _tolower(*s) - 'a' + 10;
69 * Check for overflow only if we are within range of
70 * it in the max base we support (16)
72 if (unlikely(res & (~0ull << 60))) {
73 if (res > div_u64(ULLONG_MAX - val, base))
76 res = res * base + val;
82 rv |= KSTRTOX_OVERFLOW;
86 static int _kstrtoull(const char *s, unsigned int base, unsigned long long *res)
88 unsigned long long _res;
91 s = _parse_integer_fixup_radix(s, &base);
92 rv = _parse_integer(s, base, &_res);
93 if (rv & KSTRTOX_OVERFLOW)
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.
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
122 int kstrtoull(const char *s, unsigned int base, unsigned long long *res)
126 return _kstrtoull(s, base, res);
128 EXPORT_SYMBOL(kstrtoull);
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.
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
146 int kstrtoll(const char *s, unsigned int base, long long *res)
148 unsigned long long tmp;
152 rv = _kstrtoull(s + 1, base, &tmp);
155 if ((long long)(-tmp) >= 0)
159 rv = kstrtoull(s, base, &tmp);
162 if ((long long)tmp < 0)
168 EXPORT_SYMBOL(kstrtoll);
170 /* Internal, do not use. */
171 int _kstrtoul(const char *s, unsigned int base, unsigned long *res)
173 unsigned long long tmp;
176 rv = kstrtoull(s, base, &tmp);
179 if (tmp != (unsigned long long)(unsigned long)tmp)
184 EXPORT_SYMBOL(_kstrtoul);
186 /* Internal, do not use. */
187 int _kstrtol(const char *s, unsigned int base, long *res)
192 rv = kstrtoll(s, base, &tmp);
195 if (tmp != (long long)(long)tmp)
200 EXPORT_SYMBOL(_kstrtol);
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.
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
218 int kstrtouint(const char *s, unsigned int base, unsigned int *res)
220 unsigned long long tmp;
223 rv = kstrtoull(s, base, &tmp);
226 if (tmp != (unsigned long long)(unsigned int)tmp)
231 EXPORT_SYMBOL(kstrtouint);
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.
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
249 int kstrtoint(const char *s, unsigned int base, int *res)
254 rv = kstrtoll(s, base, &tmp);
257 if (tmp != (long long)(int)tmp)
262 EXPORT_SYMBOL(kstrtoint);
264 int kstrtou16(const char *s, unsigned int base, u16 *res)
266 unsigned long long tmp;
269 rv = kstrtoull(s, base, &tmp);
272 if (tmp != (unsigned long long)(u16)tmp)
277 EXPORT_SYMBOL(kstrtou16);
279 int kstrtos16(const char *s, unsigned int base, s16 *res)
284 rv = kstrtoll(s, base, &tmp);
287 if (tmp != (long long)(s16)tmp)
292 EXPORT_SYMBOL(kstrtos16);
294 int kstrtou8(const char *s, unsigned int base, u8 *res)
296 unsigned long long tmp;
299 rv = kstrtoull(s, base, &tmp);
302 if (tmp != (unsigned long long)(u8)tmp)
307 EXPORT_SYMBOL(kstrtou8);
309 int kstrtos8(const char *s, unsigned int base, s8 *res)
314 rv = kstrtoll(s, base, &tmp);
317 if (tmp != (long long)(s8)tmp)
322 EXPORT_SYMBOL(kstrtos8);
324 #define kstrto_from_user(f, g, type) \
325 int f(const char __user *s, size_t count, unsigned int base, type *res) \
327 /* sign, base 2 representation, newline, terminator */ \
328 char buf[1 + sizeof(type) * 8 + 1 + 1]; \
330 count = min(count, sizeof(buf) - 1); \
331 if (copy_from_user(buf, s, count)) \
334 return g(buf, base, res); \
338 kstrto_from_user(kstrtoull_from_user, kstrtoull, unsigned long long);
339 kstrto_from_user(kstrtoll_from_user, kstrtoll, long long);
340 kstrto_from_user(kstrtoul_from_user, kstrtoul, unsigned long);
341 kstrto_from_user(kstrtol_from_user, kstrtol, long);
342 kstrto_from_user(kstrtouint_from_user, kstrtouint, unsigned int);
343 kstrto_from_user(kstrtoint_from_user, kstrtoint, int);
344 kstrto_from_user(kstrtou16_from_user, kstrtou16, u16);
345 kstrto_from_user(kstrtos16_from_user, kstrtos16, s16);
346 kstrto_from_user(kstrtou8_from_user, kstrtou8, u8);
347 kstrto_from_user(kstrtos8_from_user, kstrtos8, s8);