xref: /openbmc/linux/arch/arm/boot/compressed/string.c (revision f3539c12)
1 /*
2  * arch/arm/boot/compressed/string.c
3  *
4  * Small subset of simple string routines
5  */
6 
7 #include <linux/string.h>
8 
9 void *memcpy(void *__dest, __const void *__src, size_t __n)
10 {
11 	int i = 0;
12 	unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;
13 
14 	for (i = __n >> 3; i > 0; i--) {
15 		*d++ = *s++;
16 		*d++ = *s++;
17 		*d++ = *s++;
18 		*d++ = *s++;
19 		*d++ = *s++;
20 		*d++ = *s++;
21 		*d++ = *s++;
22 		*d++ = *s++;
23 	}
24 
25 	if (__n & 1 << 2) {
26 		*d++ = *s++;
27 		*d++ = *s++;
28 		*d++ = *s++;
29 		*d++ = *s++;
30 	}
31 
32 	if (__n & 1 << 1) {
33 		*d++ = *s++;
34 		*d++ = *s++;
35 	}
36 
37 	if (__n & 1)
38 		*d++ = *s++;
39 
40 	return __dest;
41 }
42 
43 void *memmove(void *__dest, __const void *__src, size_t count)
44 {
45 	unsigned char *d = __dest;
46 	const unsigned char *s = __src;
47 
48 	if (__dest == __src)
49 		return __dest;
50 
51 	if (__dest < __src)
52 		return memcpy(__dest, __src, count);
53 
54 	while (count--)
55 		d[count] = s[count];
56 	return __dest;
57 }
58 
59 size_t strlen(const char *s)
60 {
61 	const char *sc = s;
62 
63 	while (*sc != '\0')
64 		sc++;
65 	return sc - s;
66 }
67 
68 size_t strnlen(const char *s, size_t count)
69 {
70 	const char *sc;
71 
72 	for (sc = s; count-- && *sc != '\0'; ++sc)
73 		/* nothing */;
74 	return sc - s;
75 }
76 
77 int memcmp(const void *cs, const void *ct, size_t count)
78 {
79 	const unsigned char *su1 = cs, *su2 = ct, *end = su1 + count;
80 	int res = 0;
81 
82 	while (su1 < end) {
83 		res = *su1++ - *su2++;
84 		if (res)
85 			break;
86 	}
87 	return res;
88 }
89 
90 int strcmp(const char *cs, const char *ct)
91 {
92 	unsigned char c1, c2;
93 	int res = 0;
94 
95 	do {
96 		c1 = *cs++;
97 		c2 = *ct++;
98 		res = c1 - c2;
99 		if (res)
100 			break;
101 	} while (c1);
102 	return res;
103 }
104 
105 void *memchr(const void *s, int c, size_t count)
106 {
107 	const unsigned char *p = s;
108 
109 	while (count--)
110 		if ((unsigned char)c == *p++)
111 			return (void *)(p - 1);
112 	return NULL;
113 }
114 
115 char *strchr(const char *s, int c)
116 {
117 	while (*s != (char)c)
118 		if (*s++ == '\0')
119 			return NULL;
120 	return (char *)s;
121 }
122 
123 #undef memset
124 
125 void *memset(void *s, int c, size_t count)
126 {
127 	char *xs = s;
128 	while (count--)
129 		*xs++ = c;
130 	return s;
131 }
132 
133 void __memzero(void *s, size_t count)
134 {
135 	memset(s, 0, count);
136 }
137