| 1,43 → 1,40 |
|---|
| # _strncat() Author: Kees J. Bot |
| # 1 Jan 1994 |
| # char *_strncat(char *s1, const char *s2, size_t edx) |
| # Append string s2 to s1. |
| # |
| /* _strncat() Author: Kees J. Bot */ |
| /* 1 Jan 1994 */ |
| |
| .intel_syntax |
| /* char *_strncat(char *s1, const char *s2, size_t edx) */ |
| /* Append string s2 to s1. */ |
| /* */ |
| #include "asm.h" |
| |
| .global __strncat |
| ENTRY(_strncat) |
| push %ebp |
| movl %esp, %ebp |
| push %esi |
| push %edi |
| movl 8(%ebp), %edi /* String s1 */ |
| movl $-1, %ecx |
| xorb %al, %al /* Null byte */ |
| cld |
| |
| .text |
| .align 16 |
| __strncat: |
| push ebp |
| mov ebp, esp |
| push esi |
| push edi |
| mov edi, [ebp+8] # String s1 |
| mov ecx, -1 |
| xorb al, al # Null byte |
| cld |
| repne |
| scasb # Look for the zero byte in s1 |
| dec edi # Back one up (and clear 'Z' flag) |
| push edi # Save end of s1 |
| mov edi, [12+ebp] # edi = string s2 |
| mov ecx, edx # Maximum count |
| repne |
| scasb # Look for the end of s2 |
| repne scasb /* Look for the zero byte in s1 */ |
| decl %edi /* Back one up (and clear 'Z' flag) */ |
| push %edi /* Save end of s1 */ |
| movl 12(%ebp), %edi /* edi = string s2 */ |
| movl %edx, %ecx /* Maximum count */ |
| |
| repne scasb /* Look for the end of s2 */ |
| jne no0 |
| inc ecx # Exclude null byte |
| no0: sub edx, ecx # Number of bytes in s2 |
| mov ecx, edx |
| mov esi, [12+ebp] # esi = string s2 |
| pop edi # edi = end of string s1 |
| rep |
| movsb # Copy bytes |
| stosb # Add a terminating null |
| mov eax, [8+ebp] # Return s1 |
| pop edi |
| pop esi |
| pop ebp |
| incl %ecx /* Exclude null byte */ |
| no0: |
| subl %ecx, %edx /* Number of bytes in s2 */ |
| movl %edx, %ecx |
| movl 12(%ebp), %esi /* esi = string s2 */ |
| pop %edi /* edi = end of string s1 */ |
| |
| rep movsb /* Copy bytes */ |
| stosb /* Add a terminating null */ |
| movl 8(%ebp), %eax /* Return s1 */ |
| pop %edi |
| pop %esi |
| pop %ebp |
| ret |