1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun /*
3*4882a593Smuzhiyun * arch/arm/boot/compressed/string.c
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun * Small subset of simple string routines
6*4882a593Smuzhiyun */
7*4882a593Smuzhiyun
8*4882a593Smuzhiyun #include <linux/string.h>
9*4882a593Smuzhiyun
memcpy(void * __dest,__const void * __src,size_t __n)10*4882a593Smuzhiyun void *memcpy(void *__dest, __const void *__src, size_t __n)
11*4882a593Smuzhiyun {
12*4882a593Smuzhiyun int i = 0;
13*4882a593Smuzhiyun unsigned char *d = (unsigned char *)__dest, *s = (unsigned char *)__src;
14*4882a593Smuzhiyun
15*4882a593Smuzhiyun for (i = __n >> 3; i > 0; i--) {
16*4882a593Smuzhiyun *d++ = *s++;
17*4882a593Smuzhiyun *d++ = *s++;
18*4882a593Smuzhiyun *d++ = *s++;
19*4882a593Smuzhiyun *d++ = *s++;
20*4882a593Smuzhiyun *d++ = *s++;
21*4882a593Smuzhiyun *d++ = *s++;
22*4882a593Smuzhiyun *d++ = *s++;
23*4882a593Smuzhiyun *d++ = *s++;
24*4882a593Smuzhiyun }
25*4882a593Smuzhiyun
26*4882a593Smuzhiyun if (__n & 1 << 2) {
27*4882a593Smuzhiyun *d++ = *s++;
28*4882a593Smuzhiyun *d++ = *s++;
29*4882a593Smuzhiyun *d++ = *s++;
30*4882a593Smuzhiyun *d++ = *s++;
31*4882a593Smuzhiyun }
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun if (__n & 1 << 1) {
34*4882a593Smuzhiyun *d++ = *s++;
35*4882a593Smuzhiyun *d++ = *s++;
36*4882a593Smuzhiyun }
37*4882a593Smuzhiyun
38*4882a593Smuzhiyun if (__n & 1)
39*4882a593Smuzhiyun *d++ = *s++;
40*4882a593Smuzhiyun
41*4882a593Smuzhiyun return __dest;
42*4882a593Smuzhiyun }
43*4882a593Smuzhiyun
memmove(void * __dest,__const void * __src,size_t count)44*4882a593Smuzhiyun void *memmove(void *__dest, __const void *__src, size_t count)
45*4882a593Smuzhiyun {
46*4882a593Smuzhiyun unsigned char *d = __dest;
47*4882a593Smuzhiyun const unsigned char *s = __src;
48*4882a593Smuzhiyun
49*4882a593Smuzhiyun if (__dest == __src)
50*4882a593Smuzhiyun return __dest;
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun if (__dest < __src)
53*4882a593Smuzhiyun return memcpy(__dest, __src, count);
54*4882a593Smuzhiyun
55*4882a593Smuzhiyun while (count--)
56*4882a593Smuzhiyun d[count] = s[count];
57*4882a593Smuzhiyun return __dest;
58*4882a593Smuzhiyun }
59*4882a593Smuzhiyun
strlen(const char * s)60*4882a593Smuzhiyun size_t strlen(const char *s)
61*4882a593Smuzhiyun {
62*4882a593Smuzhiyun const char *sc = s;
63*4882a593Smuzhiyun
64*4882a593Smuzhiyun while (*sc != '\0')
65*4882a593Smuzhiyun sc++;
66*4882a593Smuzhiyun return sc - s;
67*4882a593Smuzhiyun }
68*4882a593Smuzhiyun
strnlen(const char * s,size_t count)69*4882a593Smuzhiyun size_t strnlen(const char *s, size_t count)
70*4882a593Smuzhiyun {
71*4882a593Smuzhiyun const char *sc;
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun for (sc = s; count-- && *sc != '\0'; ++sc)
74*4882a593Smuzhiyun /* nothing */;
75*4882a593Smuzhiyun return sc - s;
76*4882a593Smuzhiyun }
77*4882a593Smuzhiyun
memcmp(const void * cs,const void * ct,size_t count)78*4882a593Smuzhiyun int memcmp(const void *cs, const void *ct, size_t count)
79*4882a593Smuzhiyun {
80*4882a593Smuzhiyun const unsigned char *su1 = cs, *su2 = ct, *end = su1 + count;
81*4882a593Smuzhiyun int res = 0;
82*4882a593Smuzhiyun
83*4882a593Smuzhiyun while (su1 < end) {
84*4882a593Smuzhiyun res = *su1++ - *su2++;
85*4882a593Smuzhiyun if (res)
86*4882a593Smuzhiyun break;
87*4882a593Smuzhiyun }
88*4882a593Smuzhiyun return res;
89*4882a593Smuzhiyun }
90*4882a593Smuzhiyun
strcmp(const char * cs,const char * ct)91*4882a593Smuzhiyun int strcmp(const char *cs, const char *ct)
92*4882a593Smuzhiyun {
93*4882a593Smuzhiyun unsigned char c1, c2;
94*4882a593Smuzhiyun int res = 0;
95*4882a593Smuzhiyun
96*4882a593Smuzhiyun do {
97*4882a593Smuzhiyun c1 = *cs++;
98*4882a593Smuzhiyun c2 = *ct++;
99*4882a593Smuzhiyun res = c1 - c2;
100*4882a593Smuzhiyun if (res)
101*4882a593Smuzhiyun break;
102*4882a593Smuzhiyun } while (c1);
103*4882a593Smuzhiyun return res;
104*4882a593Smuzhiyun }
105*4882a593Smuzhiyun
memchr(const void * s,int c,size_t count)106*4882a593Smuzhiyun void *memchr(const void *s, int c, size_t count)
107*4882a593Smuzhiyun {
108*4882a593Smuzhiyun const unsigned char *p = s;
109*4882a593Smuzhiyun
110*4882a593Smuzhiyun while (count--)
111*4882a593Smuzhiyun if ((unsigned char)c == *p++)
112*4882a593Smuzhiyun return (void *)(p - 1);
113*4882a593Smuzhiyun return NULL;
114*4882a593Smuzhiyun }
115*4882a593Smuzhiyun
strchr(const char * s,int c)116*4882a593Smuzhiyun char *strchr(const char *s, int c)
117*4882a593Smuzhiyun {
118*4882a593Smuzhiyun while (*s != (char)c)
119*4882a593Smuzhiyun if (*s++ == '\0')
120*4882a593Smuzhiyun return NULL;
121*4882a593Smuzhiyun return (char *)s;
122*4882a593Smuzhiyun }
123*4882a593Smuzhiyun
strrchr(const char * s,int c)124*4882a593Smuzhiyun char *strrchr(const char *s, int c)
125*4882a593Smuzhiyun {
126*4882a593Smuzhiyun const char *last = NULL;
127*4882a593Smuzhiyun do {
128*4882a593Smuzhiyun if (*s == (char)c)
129*4882a593Smuzhiyun last = s;
130*4882a593Smuzhiyun } while (*s++);
131*4882a593Smuzhiyun return (char *)last;
132*4882a593Smuzhiyun }
133*4882a593Smuzhiyun
134*4882a593Smuzhiyun #undef memset
135*4882a593Smuzhiyun
memset(void * s,int c,size_t count)136*4882a593Smuzhiyun void *memset(void *s, int c, size_t count)
137*4882a593Smuzhiyun {
138*4882a593Smuzhiyun char *xs = s;
139*4882a593Smuzhiyun while (count--)
140*4882a593Smuzhiyun *xs++ = c;
141*4882a593Smuzhiyun return s;
142*4882a593Smuzhiyun }
143