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comparison src/usr/ulib.c @ 0:83c23a36980d

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Init
author Tatsuki IHA <e125716@ie.u-ryukyu.ac.jp>
date Fri, 26 May 2017 23:11:05 +0900
parents
children 2617849843ec
comparison
equal deleted inserted replaced
-1:000000000000 0:83c23a36980d
1 #include "types.h"
2 #include "stat.h"
3 #include "fcntl.h"
4 #include "user.h"
5
6 char*
7 strcpy(char *s, char *t)
8 {
9 char *os;
10
11 os = s;
12 while((*s++ = *t++) != 0)
13 ;
14 return os;
15 }
16
17 int
18 strcmp(const char *p, const char *q)
19 {
20 while(*p && *p == *q)
21 p++, q++;
22 return (uchar)*p - (uchar)*q;
23 }
24
25 uint
26 strlen(char *s)
27 {
28 int n;
29
30 for(n = 0; s[n]; n++)
31 ;
32 return n;
33 }
34
35 void*
36 memset(void *dst, int v, uint n)
37 {
38 uint8 *p;
39 uint8 c;
40 uint32 val;
41 uint32 *p4;
42
43 p = dst;
44 c = v & 0xff;
45 val = (c << 24) | (c << 16) | (c << 8) | c;
46
47 // set bytes before whole uint32
48 for (; (n > 0) && ((uint)p % 4); n--, p++){
49 *p = c;
50 }
51
52 // set memory 4 bytes a time
53 p4 = (uint*)p;
54
55 for (; n >= 4; n -= 4, p4++) {
56 *p4 = val;
57 }
58
59 // set leftover one byte a time
60 p = (uint8*)p4;
61
62 for (; n > 0; n--, p++) {
63 *p = c;
64 }
65
66 return dst;
67 }
68
69 char*
70 strchr(const char *s, char c)
71 {
72 for(; *s; s++)
73 if(*s == c)
74 return (char*)s;
75 return 0;
76 }
77
78 char*
79 gets(char *buf, int max)
80 {
81 int i, cc;
82 char c;
83
84 for(i=0; i+1 < max; ){
85 cc = read(0, &c, 1);
86 if(cc < 1)
87 break;
88 buf[i++] = c;
89 if(c == '\n' || c == '\r')
90 break;
91 }
92 buf[i] = '\0';
93 return buf;
94 }
95
96 int
97 stat(char *n, struct stat *st)
98 {
99 int fd;
100 int r;
101
102 fd = open(n, O_RDONLY);
103 if(fd < 0)
104 return -1;
105 r = fstat(fd, st);
106 close(fd);
107 return r;
108 }
109
110 int
111 atoi(const char *s)
112 {
113 int n;
114
115 n = 0;
116 while('0' <= *s && *s <= '9')
117 n = n*10 + *s++ - '0';
118 return n;
119 }
120
121 void*
122 memmove(void *vdst, void *vsrc, int n)
123 {
124 char *dst, *src;
125
126 dst = vdst;
127 src = vsrc;
128 while(n-- > 0)
129 *dst++ = *src++;
130 return vdst;
131 }