1 /*
2  * arch/arm/boot/compressed/string.c
3  *
4  * Small subset of simple string routines
5  */
6 
7 #include <linux/string.h>
8 
memcpy(void * __dest,__const void * __src,size_t __n)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 
memmove(void * __dest,__const void * __src,size_t count)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 
strlen(const char * s)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 
memcmp(const void * cs,const void * ct,size_t count)68 int memcmp(const void *cs, const void *ct, size_t count)
69 {
70 	const unsigned char *su1 = cs, *su2 = ct, *end = su1 + count;
71 	int res = 0;
72 
73 	while (su1 < end) {
74 		res = *su1++ - *su2++;
75 		if (res)
76 			break;
77 	}
78 	return res;
79 }
80 
strcmp(const char * cs,const char * ct)81 int strcmp(const char *cs, const char *ct)
82 {
83 	unsigned char c1, c2;
84 	int res = 0;
85 
86 	do {
87 		c1 = *cs++;
88 		c2 = *ct++;
89 		res = c1 - c2;
90 		if (res)
91 			break;
92 	} while (c1);
93 	return res;
94 }
95 
memchr(const void * s,int c,size_t count)96 void *memchr(const void *s, int c, size_t count)
97 {
98 	const unsigned char *p = s;
99 
100 	while (count--)
101 		if ((unsigned char)c == *p++)
102 			return (void *)(p - 1);
103 	return NULL;
104 }
105 
strchr(const char * s,int c)106 char *strchr(const char *s, int c)
107 {
108 	while (*s != (char)c)
109 		if (*s++ == '\0')
110 			return NULL;
111 	return (char *)s;
112 }
113 
114 #undef memset
115 
memset(void * s,int c,size_t count)116 void *memset(void *s, int c, size_t count)
117 {
118 	char *xs = s;
119 	while (count--)
120 		*xs++ = c;
121 	return s;
122 }
123 
__memzero(void * s,size_t count)124 void __memzero(void *s, size_t count)
125 {
126 	memset(s, 0, count);
127 }
128