| 0,0 → 1,46 |
|---|
| # strchr() Author: Kees J. Bot 1 Jan 1994 |
| |
| # char *strchr(const char *s, int c) |
| # Look for a character in a string. |
| |
| .intel_syntax |
| |
| .globl _strchr |
| |
| .text |
| .align 16 |
| _strchr: |
| push ebp |
| mov ebp, esp |
| push edi |
| cld |
| mov edi, [ebp+8] # edi = string |
| mov edx, 16 # Look at small chunks of the string |
| next: |
| shl edx, 1 # Chunks become bigger each time |
| mov ecx, edx |
| xorb al, al # Look for the zero at the end |
| repne scasb |
| |
| pushf # Remember the flags |
| sub ecx, edx |
| neg ecx # Some or all of the chunk |
| sub edi, ecx # Step back |
| movb al, [ebp+12] # The character to look for |
| repne scasb |
| je found |
| |
| popf # Did we find the end of string earlier? |
| |
| jne next # No, try again |
| |
| xor eax, eax # Return NULL |
| pop edi |
| pop ebp |
| ret |
| found: |
| pop eax # Get rid of those flags |
| lea eax, [edi-1] # Address of byte found |
| pop edi |
| pop ebp |
| ret |