kern
annotate 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 |
| rev | line source |
|---|---|
| nuclear@0 | 1 #include <string.h> |
| nuclear@0 | 2 |
| nuclear@1 | 3 void memset(void *s, int c, size_t n) |
| nuclear@0 | 4 { |
| nuclear@0 | 5 char *ptr = s; |
| nuclear@1 | 6 while(n--) { |
| nuclear@0 | 7 *ptr++ = c; |
| nuclear@0 | 8 } |
| nuclear@0 | 9 } |
| nuclear@1 | 10 |
| nuclear@4 | 11 /* Does the same thing as memset only with 16bit values. |
| nuclear@4 | 12 * n in this case is the number of values, not the number of bytes. |
| nuclear@4 | 13 */ |
| nuclear@2 | 14 void memset16(void *s, int c, size_t n) |
| nuclear@2 | 15 { |
| nuclear@2 | 16 short *ptr = s; |
| nuclear@2 | 17 while(n--) { |
| nuclear@2 | 18 *ptr++ = c; |
| nuclear@2 | 19 } |
| nuclear@2 | 20 } |
| nuclear@2 | 21 |
| nuclear@1 | 22 void *memcpy(void *dest, const void *src, size_t n) |
| nuclear@1 | 23 { |
| nuclear@1 | 24 char *dptr = dest; |
| nuclear@1 | 25 const char *sptr = src; |
| nuclear@1 | 26 |
| nuclear@1 | 27 while(n--) { |
| nuclear@1 | 28 *dptr++ = *sptr++; |
| nuclear@1 | 29 } |
| nuclear@1 | 30 return dest; |
| nuclear@1 | 31 } |
| nuclear@1 | 32 |
| nuclear@1 | 33 void *memmove(void *dest, const void *src, size_t n) |
| nuclear@1 | 34 { |
| nuclear@1 | 35 int i; |
| nuclear@1 | 36 char *dptr; |
| nuclear@1 | 37 const char *sptr; |
| nuclear@1 | 38 |
| nuclear@1 | 39 if(dest <= src) { |
| nuclear@1 | 40 /* forward copy */ |
| nuclear@1 | 41 dptr = dest; |
| nuclear@1 | 42 sptr = src; |
| nuclear@1 | 43 for(i=0; i<n; i++) { |
| nuclear@1 | 44 *dptr++ = *sptr++; |
| nuclear@1 | 45 } |
| nuclear@1 | 46 } else { |
| nuclear@1 | 47 /* backwards copy */ |
| nuclear@1 | 48 dptr = dest + n - 1; |
| nuclear@1 | 49 sptr = src + n - 1; |
| nuclear@1 | 50 for(i=0; i<n; i++) { |
| nuclear@1 | 51 *dptr-- = *sptr--; |
| nuclear@1 | 52 } |
| nuclear@1 | 53 } |
| nuclear@1 | 54 |
| nuclear@1 | 55 return dest; |
| nuclear@1 | 56 } |