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8#include <linux/string.h>
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20#ifdef CONFIG_KASAN
21#undef memcpy
22#undef memmove
23#undef memset
24void *__memcpy(void *__dest, __const void *__src, size_t __n) __alias(memcpy);
25void *__memmove(void *__dest, __const void *__src, size_t count) __alias(memmove);
26void *__memset(void *s, int c, size_t count) __alias(memset);
27#endif
28
29void *memcpy(void *__dest, __const void *__src, size_t __n)
30{
31 int i = 0;
32 unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;
33
34 for (i = __n >> 3; i > 0; i--) {
35 *d++ = *s++;
36 *d++ = *s++;
37 *d++ = *s++;
38 *d++ = *s++;
39 *d++ = *s++;
40 *d++ = *s++;
41 *d++ = *s++;
42 *d++ = *s++;
43 }
44
45 if (__n & 1 << 2) {
46 *d++ = *s++;
47 *d++ = *s++;
48 *d++ = *s++;
49 *d++ = *s++;
50 }
51
52 if (__n & 1 << 1) {
53 *d++ = *s++;
54 *d++ = *s++;
55 }
56
57 if (__n & 1)
58 *d++ = *s++;
59
60 return __dest;
61}
62
63void *memmove(void *__dest, __const void *__src, size_t count)
64{
65 unsigned char *d = __dest;
66 const unsigned char *s = __src;
67
68 if (__dest == __src)
69 return __dest;
70
71 if (__dest < __src)
72 return memcpy(__dest, __src, count);
73
74 while (count--)
75 d[count] = s[count];
76 return __dest;
77}
78
79size_t strlen(const char *s)
80{
81 const char *sc = s;
82
83 while (*sc != '\0')
84 sc++;
85 return sc - s;
86}
87
88size_t strnlen(const char *s, size_t count)
89{
90 const char *sc;
91
92 for (sc = s; count-- && *sc != '\0'; ++sc)
93 ;
94 return sc - s;
95}
96
97int memcmp(const void *cs, const void *ct, size_t count)
98{
99 const unsigned char *su1 = cs, *su2 = ct, *end = su1 + count;
100 int res = 0;
101
102 while (su1 < end) {
103 res = *su1++ - *su2++;
104 if (res)
105 break;
106 }
107 return res;
108}
109
110int strcmp(const char *cs, const char *ct)
111{
112 unsigned char c1, c2;
113 int res = 0;
114
115 do {
116 c1 = *cs++;
117 c2 = *ct++;
118 res = c1 - c2;
119 if (res)
120 break;
121 } while (c1);
122 return res;
123}
124
125void *memchr(const void *s, int c, size_t count)
126{
127 const unsigned char *p = s;
128
129 while (count--)
130 if ((unsigned char)c == *p++)
131 return (void *)(p - 1);
132 return NULL;
133}
134
135char *strchr(const char *s, int c)
136{
137 while (*s != (char)c)
138 if (*s++ == '\0')
139 return NULL;
140 return (char *)s;
141}
142
143char *strrchr(const char *s, int c)
144{
145 const char *last = NULL;
146 do {
147 if (*s == (char)c)
148 last = s;
149 } while (*s++);
150 return (char *)last;
151}
152
153#undef memset
154
155void *memset(void *s, int c, size_t count)
156{
157 char *xs = s;
158 while (count--)
159 *xs++ = c;
160 return s;
161}
162