kern
view src/klibc/string.c @ 4:0489a34ab348
- reverted the trunk back to hardware scrolling
- added a missing include (ctype.h in term.c)
- added a comment explaining what memset16 does
- beefed up the README file
| author | John Tsiombikas <nuclear@member.fsf.org> |
|---|---|
| date | Fri, 10 Dec 2010 03:44:34 +0200 |
| parents | 86781ef20689 |
| children | 633e35c64772 |
line source
1 #include <string.h>
3 void memset(void *s, int c, size_t n)
4 {
5 char *ptr = s;
6 while(n--) {
7 *ptr++ = c;
8 }
9 }
11 /* Does the same thing as memset only with 16bit values.
12 * n in this case is the number of values, not the number of bytes.
13 */
14 void memset16(void *s, int c, size_t n)
15 {
16 short *ptr = s;
17 while(n--) {
18 *ptr++ = c;
19 }
20 }
22 void *memcpy(void *dest, const void *src, size_t n)
23 {
24 char *dptr = dest;
25 const char *sptr = src;
27 while(n--) {
28 *dptr++ = *sptr++;
29 }
30 return dest;
31 }
33 void *memmove(void *dest, const void *src, size_t n)
34 {
35 int i;
36 char *dptr;
37 const char *sptr;
39 if(dest <= src) {
40 /* forward copy */
41 dptr = dest;
42 sptr = src;
43 for(i=0; i<n; i++) {
44 *dptr++ = *sptr++;
45 }
46 } else {
47 /* backwards copy */
48 dptr = dest + n - 1;
49 sptr = src + n - 1;
50 for(i=0; i<n; i++) {
51 *dptr-- = *sptr--;
52 }
53 }
55 return dest;
56 }