1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_STRING_H_
3 #define _LINUX_STRING_H_
6 #include <linux/compiler.h> /* for inline */
7 #include <linux/types.h> /* for size_t */
8 #include <linux/stddef.h> /* for NULL */
9 #include <linux/errno.h> /* for E2BIG */
11 #include <uapi/linux/string.h>
13 extern char *strndup_user(const char __user *, long);
14 extern void *memdup_user(const void __user *, size_t);
15 extern void *vmemdup_user(const void __user *, size_t);
16 extern void *memdup_user_nul(const void __user *, size_t);
19 * Include machine specific inline routines
21 #include <asm/string.h>
23 #ifndef __HAVE_ARCH_STRCPY
24 extern char * strcpy(char *,const char *);
26 #ifndef __HAVE_ARCH_STRNCPY
27 extern char * strncpy(char *,const char *, __kernel_size_t);
29 #ifndef __HAVE_ARCH_STRLCPY
30 size_t strlcpy(char *, const char *, size_t);
32 #ifndef __HAVE_ARCH_STRSCPY
33 ssize_t strscpy(char *, const char *, size_t);
36 /* Wraps calls to strscpy()/memset(), no arch specific code required */
37 ssize_t strscpy_pad(char *dest, const char *src, size_t count);
39 #ifndef __HAVE_ARCH_STRCAT
40 extern char * strcat(char *, const char *);
42 #ifndef __HAVE_ARCH_STRNCAT
43 extern char * strncat(char *, const char *, __kernel_size_t);
45 #ifndef __HAVE_ARCH_STRLCAT
46 extern size_t strlcat(char *, const char *, __kernel_size_t);
48 #ifndef __HAVE_ARCH_STRCMP
49 extern int strcmp(const char *,const char *);
51 #ifndef __HAVE_ARCH_STRNCMP
52 extern int strncmp(const char *,const char *,__kernel_size_t);
54 #ifndef __HAVE_ARCH_STRCASECMP
55 extern int strcasecmp(const char *s1, const char *s2);
57 #ifndef __HAVE_ARCH_STRNCASECMP
58 extern int strncasecmp(const char *s1, const char *s2, size_t n);
60 #ifndef __HAVE_ARCH_STRCHR
61 extern char * strchr(const char *,int);
63 #ifndef __HAVE_ARCH_STRCHRNUL
64 extern char * strchrnul(const char *,int);
66 extern char * strnchrnul(const char *, size_t, int);
67 #ifndef __HAVE_ARCH_STRNCHR
68 extern char * strnchr(const char *, size_t, int);
70 #ifndef __HAVE_ARCH_STRRCHR
71 extern char * strrchr(const char *,int);
73 extern char * __must_check skip_spaces(const char *);
75 extern char *strim(char *);
77 static inline __must_check char *strstrip(char *str)
82 #ifndef __HAVE_ARCH_STRSTR
83 extern char * strstr(const char *, const char *);
85 #ifndef __HAVE_ARCH_STRNSTR
86 extern char * strnstr(const char *, const char *, size_t);
88 #ifndef __HAVE_ARCH_STRLEN
89 extern __kernel_size_t strlen(const char *);
91 #ifndef __HAVE_ARCH_STRNLEN
92 extern __kernel_size_t strnlen(const char *,__kernel_size_t);
94 #ifndef __HAVE_ARCH_STRPBRK
95 extern char * strpbrk(const char *,const char *);
97 #ifndef __HAVE_ARCH_STRSEP
98 extern char * strsep(char **,const char *);
100 #ifndef __HAVE_ARCH_STRSPN
101 extern __kernel_size_t strspn(const char *,const char *);
103 #ifndef __HAVE_ARCH_STRCSPN
104 extern __kernel_size_t strcspn(const char *,const char *);
107 #ifndef __HAVE_ARCH_MEMSET
108 extern void * memset(void *,int,__kernel_size_t);
111 #ifndef __HAVE_ARCH_MEMSET16
112 extern void *memset16(uint16_t *, uint16_t, __kernel_size_t);
115 #ifndef __HAVE_ARCH_MEMSET32
116 extern void *memset32(uint32_t *, uint32_t, __kernel_size_t);
119 #ifndef __HAVE_ARCH_MEMSET64
120 extern void *memset64(uint64_t *, uint64_t, __kernel_size_t);
123 static inline void *memset_l(unsigned long *p, unsigned long v,
126 if (BITS_PER_LONG == 32)
127 return memset32((uint32_t *)p, v, n);
129 return memset64((uint64_t *)p, v, n);
132 static inline void *memset_p(void **p, void *v, __kernel_size_t n)
134 if (BITS_PER_LONG == 32)
135 return memset32((uint32_t *)p, (uintptr_t)v, n);
137 return memset64((uint64_t *)p, (uintptr_t)v, n);
140 extern void **__memcat_p(void **a, void **b);
141 #define memcat_p(a, b) ({ \
142 BUILD_BUG_ON_MSG(!__same_type(*(a), *(b)), \
143 "type mismatch in memcat_p()"); \
144 (typeof(*a) *)__memcat_p((void **)(a), (void **)(b)); \
147 #ifndef __HAVE_ARCH_MEMCPY
148 extern void * memcpy(void *,const void *,__kernel_size_t);
150 #ifndef __HAVE_ARCH_MEMMOVE
151 extern void * memmove(void *,const void *,__kernel_size_t);
153 #ifndef __HAVE_ARCH_MEMSCAN
154 extern void * memscan(void *,int,__kernel_size_t);
156 #ifndef __HAVE_ARCH_MEMCMP
157 extern int memcmp(const void *,const void *,__kernel_size_t);
159 #ifndef __HAVE_ARCH_BCMP
160 extern int bcmp(const void *,const void *,__kernel_size_t);
162 #ifndef __HAVE_ARCH_MEMCHR
163 extern void * memchr(const void *,int,__kernel_size_t);
165 #ifndef __HAVE_ARCH_MEMCPY_FLUSHCACHE
166 static inline void memcpy_flushcache(void *dst, const void *src, size_t cnt)
168 memcpy(dst, src, cnt);
172 void *memchr_inv(const void *s, int c, size_t n);
173 char *strreplace(char *s, char old, char new);
175 extern void kfree_const(const void *x);
177 extern char *kstrdup(const char *s, gfp_t gfp) __malloc;
178 extern const char *kstrdup_const(const char *s, gfp_t gfp);
179 extern char *kstrndup(const char *s, size_t len, gfp_t gfp);
180 extern void *kmemdup(const void *src, size_t len, gfp_t gfp);
181 extern char *kmemdup_nul(const char *s, size_t len, gfp_t gfp);
183 extern char **argv_split(gfp_t gfp, const char *str, int *argcp);
184 extern void argv_free(char **argv);
186 extern bool sysfs_streq(const char *s1, const char *s2);
187 extern int kstrtobool(const char *s, bool *res);
188 static inline int strtobool(const char *s, bool *res)
190 return kstrtobool(s, res);
193 int match_string(const char * const *array, size_t n, const char *string);
194 int __sysfs_match_string(const char * const *array, size_t n, const char *s);
197 * sysfs_match_string - matches given string in an array
198 * @_a: array of strings
199 * @_s: string to match with
201 * Helper for __sysfs_match_string(). Calculates the size of @a automatically.
203 #define sysfs_match_string(_a, _s) __sysfs_match_string(_a, ARRAY_SIZE(_a), _s)
205 #ifdef CONFIG_BINARY_PRINTF
206 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args);
207 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf);
208 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) __printf(3, 4);
211 extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
212 const void *from, size_t available);
214 int ptr_to_hashval(const void *ptr, unsigned long *hashval_out);
217 * strstarts - does @str start with @prefix?
218 * @str: string to examine
219 * @prefix: prefix to look for.
221 static inline bool strstarts(const char *str, const char *prefix)
223 return strncmp(str, prefix, strlen(prefix)) == 0;
226 size_t memweight(const void *ptr, size_t bytes);
229 * memzero_explicit - Fill a region of memory (e.g. sensitive
230 * keying data) with 0s.
231 * @s: Pointer to the start of the area.
232 * @count: The size of the area.
234 * Note: usually using memset() is just fine (!), but in cases
235 * where clearing out _local_ data at the end of a scope is
236 * necessary, memzero_explicit() should be used instead in
237 * order to prevent the compiler from optimising away zeroing.
239 * memzero_explicit() doesn't need an arch-specific version as
240 * it just invokes the one of memset() implicitly.
242 static inline void memzero_explicit(void *s, size_t count)
249 * kbasename - return the last part of a pathname.
251 * @path: path to extract the filename from.
253 static inline const char *kbasename(const char *path)
255 const char *tail = strrchr(path, '/');
256 return tail ? tail + 1 : path;
259 #define __FORTIFY_INLINE extern __always_inline __attribute__((gnu_inline))
260 #define __RENAME(x) __asm__(#x)
262 void fortify_panic(const char *name) __noreturn __cold;
263 void __read_overflow(void) __compiletime_error("detected read beyond size of object passed as 1st parameter");
264 void __read_overflow2(void) __compiletime_error("detected read beyond size of object passed as 2nd parameter");
265 void __read_overflow3(void) __compiletime_error("detected read beyond size of object passed as 3rd parameter");
266 void __write_overflow(void) __compiletime_error("detected write beyond size of object passed as 1st parameter");
268 #if !defined(__NO_FORTIFY) && defined(__OPTIMIZE__) && defined(CONFIG_FORTIFY_SOURCE)
269 #include <linux/fortify-string.h>
273 * memcpy_and_pad - Copy one buffer to another with padding
274 * @dest: Where to copy to
275 * @dest_len: The destination buffer size
276 * @src: Where to copy from
277 * @count: The number of bytes to copy
278 * @pad: Character to use for padding if space is left in destination.
280 static inline void memcpy_and_pad(void *dest, size_t dest_len,
281 const void *src, size_t count, int pad)
283 if (dest_len > count) {
284 memcpy(dest, src, count);
285 memset(dest + count, pad, dest_len - count);
287 memcpy(dest, src, dest_len);
291 * str_has_prefix - Test if a string has a given prefix
292 * @str: The string to test
293 * @prefix: The string to see if @str starts with
295 * A common way to test a prefix of a string is to do:
296 * strncmp(str, prefix, sizeof(prefix) - 1)
298 * But this can lead to bugs due to typos, or if prefix is a pointer
299 * and not a constant. Instead use str_has_prefix().
302 * * strlen(@prefix) if @str starts with @prefix
303 * * 0 if @str does not start with @prefix
305 static __always_inline size_t str_has_prefix(const char *str, const char *prefix)
307 size_t len = strlen(prefix);
308 return strncmp(str, prefix, len) == 0 ? len : 0;
311 #endif /* _LINUX_STRING_H_ */