Details | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1627 | serge | 1 | /* memchr() Author: Kees J. Bot */ |
| 2 | /* 2 Jan 1994 */ |
||
| 3 | |||
| 4 | /* void *memchr(const void *s, int c, size_t n) */ |
||
| 5 | /* Look for a character in a chunk of memory. */ |
||
| 6 | /* */ |
||
| 7 | #include "asm.h" |
||
| 8 | |||
| 9 | ENTRY(memchr) |
||
| 10 | push %ebp |
||
| 11 | movl %esp, %ebp |
||
| 12 | push %edi |
||
| 13 | movl 8(%ebp), %edi /* edi = string */ |
||
| 14 | movb 12(%ebp), %al /* The character to look for */ |
||
| 15 | movl 16(%ebp), %ecx /* Length */ |
||
| 16 | cmpb $1, %cl /* 'Z' bit must be clear if ecx = 0 */ |
||
| 17 | cld |
||
| 18 | |||
| 19 | repne scasb |
||
| 20 | jne failure |
||
| 21 | leal -1(%edi), %eax /* Found */ |
||
| 22 | pop %edi |
||
| 23 | pop %ebp |
||
| 24 | ret |
||
| 25 | failure: |
||
| 26 | xorl %eax, %eax |
||
| 27 | pop %edi |
||
| 28 | pop %ebp |
||
| 29 | ret |