Rev 1408 | Details | Compare with Previous | Last modification | View Log | RSS feed
| Rev | Author | Line No. | Line |
|---|---|---|---|
| 1627 | serge | 1 | /* _strnlen() Author: Kees J. Bot */ |
| 2 | /* 1 Jan 1994 */ |
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| 1408 | serge | 3 | |
| 1627 | serge | 4 | /* size_t _strnlen(const char *s, size_t ecx) */ |
| 5 | /* Return the length of a string. */ |
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| 6 | /* */ |
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| 7 | #include "asm.h" |
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| 1408 | serge | 8 | |
| 1627 | serge | 9 | ENTRY(_strnlen) |
| 10 | push %ebp |
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| 11 | movl %esp, %ebp |
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| 12 | push %edi |
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| 13 | movl 8(%ebp), %edi /* edi = string */ |
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| 14 | xorb %al, %al /* Look for a zero byte */ |
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| 15 | movl %ecx, %edx /* Save maximum count */ |
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| 16 | cmpb $1, %cl /* 'Z' bit must be clear if ecx = 0 */ |
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| 17 | cld |
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| 1408 | serge | 18 | |
| 1627 | serge | 19 | repne scasb /* Look for zero */ |
| 20 | jne no0 |
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| 21 | incl %ecx /* Don't count zero byte */ |
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| 1408 | serge | 22 | no0: |
| 1627 | serge | 23 | movl %edx, %eax |
| 24 | subl %ecx, %eax /* Compute bytes scanned */ |
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| 25 | pop %edi |
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| 26 | pop %ebp |
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| 27 | ret |