1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _LINUX_STRING_H_ |
3 | #define _LINUX_STRING_H_ |
4 | |
5 | #include <linux/compiler.h> /* for inline */ |
6 | #include <linux/types.h> /* for size_t */ |
7 | #include <linux/stddef.h> /* for NULL */ |
8 | #include <linux/errno.h> /* for E2BIG */ |
9 | #include <linux/stdarg.h> |
10 | #include <uapi/linux/string.h> |
11 | |
12 | extern char *strndup_user(const char __user *, long); |
13 | extern void *memdup_user(const void __user *, size_t); |
14 | extern void *vmemdup_user(const void __user *, size_t); |
15 | extern void *memdup_user_nul(const void __user *, size_t); |
16 | |
17 | /* |
18 | * Include machine specific inline routines |
19 | */ |
20 | #include <asm/string.h> |
21 | |
22 | #ifndef __HAVE_ARCH_STRCPY |
23 | extern char * strcpy(char *,const char *); |
24 | #endif |
25 | #ifndef __HAVE_ARCH_STRNCPY |
26 | extern char * strncpy(char *,const char *, __kernel_size_t); |
27 | #endif |
28 | #ifndef __HAVE_ARCH_STRLCPY |
29 | size_t strlcpy(char *, const char *, size_t); |
30 | #endif |
31 | #ifndef __HAVE_ARCH_STRSCPY |
32 | ssize_t strscpy(char *, const char *, size_t); |
33 | #endif |
34 | |
35 | /* Wraps calls to strscpy()/memset(), no arch specific code required */ |
36 | ssize_t strscpy_pad(char *dest, const char *src, size_t count); |
37 | |
38 | #ifndef __HAVE_ARCH_STRCAT |
39 | extern char * strcat(char *, const char *); |
40 | #endif |
41 | #ifndef __HAVE_ARCH_STRNCAT |
42 | extern char * strncat(char *, const char *, __kernel_size_t); |
43 | #endif |
44 | #ifndef __HAVE_ARCH_STRLCAT |
45 | extern size_t strlcat(char *, const char *, __kernel_size_t); |
46 | #endif |
47 | #ifndef __HAVE_ARCH_STRCMP |
48 | extern int strcmp(const char *,const char *); |
49 | #endif |
50 | #ifndef __HAVE_ARCH_STRNCMP |
51 | extern int strncmp(const char *,const char *,__kernel_size_t); |
52 | #endif |
53 | #ifndef __HAVE_ARCH_STRCASECMP |
54 | extern int strcasecmp(const char *s1, const char *s2); |
55 | #endif |
56 | #ifndef __HAVE_ARCH_STRNCASECMP |
57 | extern int strncasecmp(const char *s1, const char *s2, size_t n); |
58 | #endif |
59 | #ifndef __HAVE_ARCH_STRCHR |
60 | extern char * strchr(const char *,int); |
61 | #endif |
62 | #ifndef __HAVE_ARCH_STRCHRNUL |
63 | extern char * strchrnul(const char *,int); |
64 | #endif |
65 | extern char * strnchrnul(const char *, size_t, int); |
66 | #ifndef __HAVE_ARCH_STRNCHR |
67 | extern char * strnchr(const char *, size_t, int); |
68 | #endif |
69 | #ifndef __HAVE_ARCH_STRRCHR |
70 | extern char * strrchr(const char *,int); |
71 | #endif |
72 | extern char * __must_check skip_spaces(const char *); |
73 | |
74 | extern char *strim(char *); |
75 | |
76 | static inline __must_check char *strstrip(char *str) |
77 | { |
78 | return strim(str); |
79 | } |
80 | |
81 | #ifndef __HAVE_ARCH_STRSTR |
82 | extern char * strstr(const char *, const char *); |
83 | #endif |
84 | #ifndef __HAVE_ARCH_STRNSTR |
85 | extern char * strnstr(const char *, const char *, size_t); |
86 | #endif |
87 | #ifndef __HAVE_ARCH_STRLEN |
88 | extern __kernel_size_t strlen(const char *); |
89 | #endif |
90 | #ifndef __HAVE_ARCH_STRNLEN |
91 | extern __kernel_size_t strnlen(const char *,__kernel_size_t); |
92 | #endif |
93 | #ifndef __HAVE_ARCH_STRPBRK |
94 | extern char * strpbrk(const char *,const char *); |
95 | #endif |
96 | #ifndef __HAVE_ARCH_STRSEP |
97 | extern char * strsep(char **,const char *); |
98 | #endif |
99 | #ifndef __HAVE_ARCH_STRSPN |
100 | extern __kernel_size_t strspn(const char *,const char *); |
101 | #endif |
102 | #ifndef __HAVE_ARCH_STRCSPN |
103 | extern __kernel_size_t strcspn(const char *,const char *); |
104 | #endif |
105 | |
106 | #ifndef __HAVE_ARCH_MEMSET |
107 | extern void * memset(void *,int,__kernel_size_t); |
108 | #endif |
109 | |
110 | #ifndef __HAVE_ARCH_MEMSET16 |
111 | extern void *memset16(uint16_t *, uint16_t, __kernel_size_t); |
112 | #endif |
113 | |
114 | #ifndef __HAVE_ARCH_MEMSET32 |
115 | extern void *memset32(uint32_t *, uint32_t, __kernel_size_t); |
116 | #endif |
117 | |
118 | #ifndef __HAVE_ARCH_MEMSET64 |
119 | extern void *memset64(uint64_t *, uint64_t, __kernel_size_t); |
120 | #endif |
121 | |
122 | static inline void *memset_l(unsigned long *p, unsigned long v, |
123 | __kernel_size_t n) |
124 | { |
125 | if (BITS_PER_LONG == 32) |
126 | return memset32((uint32_t *)p, v, n); |
127 | else |
128 | return memset64((uint64_t *)p, v, n); |
129 | } |
130 | |
131 | static inline void *memset_p(void **p, void *v, __kernel_size_t n) |
132 | { |
133 | if (BITS_PER_LONG == 32) |
134 | return memset32((uint32_t *)p, (uintptr_t)v, n); |
135 | else |
136 | return memset64((uint64_t *)p, (uintptr_t)v, n); |
137 | } |
138 | |
139 | extern void **__memcat_p(void **a, void **b); |
140 | #define memcat_p(a, b) ({ \ |
141 | BUILD_BUG_ON_MSG(!__same_type(*(a), *(b)), \ |
142 | "type mismatch in memcat_p()"); \ |
143 | (typeof(*a) *)__memcat_p((void **)(a), (void **)(b)); \ |
144 | }) |
145 | |
146 | #ifndef __HAVE_ARCH_MEMCPY |
147 | extern void * memcpy(void *,const void *,__kernel_size_t); |
148 | #endif |
149 | #ifndef __HAVE_ARCH_MEMMOVE |
150 | extern void * memmove(void *,const void *,__kernel_size_t); |
151 | #endif |
152 | #ifndef __HAVE_ARCH_MEMSCAN |
153 | extern void * memscan(void *,int,__kernel_size_t); |
154 | #endif |
155 | #ifndef __HAVE_ARCH_MEMCMP |
156 | extern int memcmp(const void *,const void *,__kernel_size_t); |
157 | #endif |
158 | #ifndef __HAVE_ARCH_BCMP |
159 | extern int bcmp(const void *,const void *,__kernel_size_t); |
160 | #endif |
161 | #ifndef __HAVE_ARCH_MEMCHR |
162 | extern void * memchr(const void *,int,__kernel_size_t); |
163 | #endif |
164 | #ifndef __HAVE_ARCH_MEMCPY_FLUSHCACHE |
165 | static inline void memcpy_flushcache(void *dst, const void *src, size_t cnt) |
166 | { |
167 | memcpy(dst, src, cnt); |
168 | } |
169 | #endif |
170 | |
171 | void *memchr_inv(const void *s, int c, size_t n); |
172 | char *strreplace(char *s, char old, char new); |
173 | |
174 | extern void kfree_const(const void *x); |
175 | |
176 | extern char *kstrdup(const char *s, gfp_t gfp) __malloc; |
177 | extern const char *kstrdup_const(const char *s, gfp_t gfp); |
178 | extern char *kstrndup(const char *s, size_t len, gfp_t gfp); |
179 | extern void *kmemdup(const void *src, size_t len, gfp_t gfp); |
180 | extern char *kmemdup_nul(const char *s, size_t len, gfp_t gfp); |
181 | |
182 | extern char **argv_split(gfp_t gfp, const char *str, int *argcp); |
183 | extern void argv_free(char **argv); |
184 | |
185 | extern bool sysfs_streq(const char *s1, const char *s2); |
186 | int match_string(const char * const *array, size_t n, const char *string); |
187 | int __sysfs_match_string(const char * const *array, size_t n, const char *s); |
188 | |
189 | /** |
190 | * sysfs_match_string - matches given string in an array |
191 | * @_a: array of strings |
192 | * @_s: string to match with |
193 | * |
194 | * Helper for __sysfs_match_string(). Calculates the size of @a automatically. |
195 | */ |
196 | #define sysfs_match_string(_a, _s) __sysfs_match_string(_a, ARRAY_SIZE(_a), _s) |
197 | |
198 | #ifdef CONFIG_BINARY_PRINTF |
199 | int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args); |
200 | int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf); |
201 | int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) __printf(3, 4); |
202 | #endif |
203 | |
204 | extern ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos, |
205 | const void *from, size_t available); |
206 | |
207 | int ptr_to_hashval(const void *ptr, unsigned long *hashval_out); |
208 | |
209 | /** |
210 | * strstarts - does @str start with @prefix? |
211 | * @str: string to examine |
212 | * @prefix: prefix to look for. |
213 | */ |
214 | static inline bool strstarts(const char *str, const char *prefix) |
215 | { |
216 | return strncmp(str, prefix, strlen(prefix)) == 0; |
217 | } |
218 | |
219 | size_t memweight(const void *ptr, size_t bytes); |
220 | |
221 | /** |
222 | * memzero_explicit - Fill a region of memory (e.g. sensitive |
223 | * keying data) with 0s. |
224 | * @s: Pointer to the start of the area. |
225 | * @count: The size of the area. |
226 | * |
227 | * Note: usually using memset() is just fine (!), but in cases |
228 | * where clearing out _local_ data at the end of a scope is |
229 | * necessary, memzero_explicit() should be used instead in |
230 | * order to prevent the compiler from optimising away zeroing. |
231 | * |
232 | * memzero_explicit() doesn't need an arch-specific version as |
233 | * it just invokes the one of memset() implicitly. |
234 | */ |
235 | static inline void memzero_explicit(void *s, size_t count) |
236 | { |
237 | memset(s, 0, count); |
238 | barrier_data(s); |
239 | } |
240 | |
241 | /** |
242 | * kbasename - return the last part of a pathname. |
243 | * |
244 | * @path: path to extract the filename from. |
245 | */ |
246 | static inline const char *kbasename(const char *path) |
247 | { |
248 | const char *tail = strrchr(path, '/'); |
249 | return tail ? tail + 1 : path; |
250 | } |
251 | |
252 | #if !defined(__NO_FORTIFY) && defined(__OPTIMIZE__) && defined(CONFIG_FORTIFY_SOURCE) |
253 | #include <linux/fortify-string.h> |
254 | #endif |
255 | #ifndef unsafe_memcpy |
256 | #define unsafe_memcpy(dst, src, bytes, justification) \ |
257 | memcpy(dst, src, bytes) |
258 | #endif |
259 | |
260 | void memcpy_and_pad(void *dest, size_t dest_len, const void *src, size_t count, |
261 | int pad); |
262 | |
263 | /** |
264 | * memset_after - Set a value after a struct member to the end of a struct |
265 | * |
266 | * @obj: Address of target struct instance |
267 | * @v: Byte value to repeatedly write |
268 | * @member: after which struct member to start writing bytes |
269 | * |
270 | * This is good for clearing padding following the given member. |
271 | */ |
272 | #define memset_after(obj, v, member) \ |
273 | ({ \ |
274 | u8 *__ptr = (u8 *)(obj); \ |
275 | typeof(v) __val = (v); \ |
276 | memset(__ptr + offsetofend(typeof(*(obj)), member), __val, \ |
277 | sizeof(*(obj)) - offsetofend(typeof(*(obj)), member)); \ |
278 | }) |
279 | |
280 | /** |
281 | * memset_startat - Set a value starting at a member to the end of a struct |
282 | * |
283 | * @obj: Address of target struct instance |
284 | * @v: Byte value to repeatedly write |
285 | * @member: struct member to start writing at |
286 | * |
287 | * Note that if there is padding between the prior member and the target |
288 | * member, memset_after() should be used to clear the prior padding. |
289 | */ |
290 | #define memset_startat(obj, v, member) \ |
291 | ({ \ |
292 | u8 *__ptr = (u8 *)(obj); \ |
293 | typeof(v) __val = (v); \ |
294 | memset(__ptr + offsetof(typeof(*(obj)), member), __val, \ |
295 | sizeof(*(obj)) - offsetof(typeof(*(obj)), member)); \ |
296 | }) |
297 | |
298 | /** |
299 | * str_has_prefix - Test if a string has a given prefix |
300 | * @str: The string to test |
301 | * @prefix: The string to see if @str starts with |
302 | * |
303 | * A common way to test a prefix of a string is to do: |
304 | * strncmp(str, prefix, sizeof(prefix) - 1) |
305 | * |
306 | * But this can lead to bugs due to typos, or if prefix is a pointer |
307 | * and not a constant. Instead use str_has_prefix(). |
308 | * |
309 | * Returns: |
310 | * * strlen(@prefix) if @str starts with @prefix |
311 | * * 0 if @str does not start with @prefix |
312 | */ |
313 | static __always_inline size_t str_has_prefix(const char *str, const char *prefix) |
314 | { |
315 | size_t len = strlen(prefix); |
316 | return strncmp(str, prefix, len) == 0 ? len : 0; |
317 | } |
318 | |
319 | #endif /* _LINUX_STRING_H_ */ |
320 | |