42 lines
874 B
ArmAsm
Executable file
42 lines
874 B
ArmAsm
Executable file
! _strncat() Author: Kees J. Bot
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! 1 Jan 1994
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.sect .text; .sect .rom; .sect .data; .sect .bss
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! char *_strncat(char *s1, const char *s2, size_t edx)
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! Append string s2 to s1.
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!
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.sect .text
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.define __strncat
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.align 16
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__strncat:
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push ebp
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mov ebp, esp
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push esi
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push edi
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mov edi, 8(ebp) ! String s1
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mov ecx, -1
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xorb al, al ! Null byte
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cld
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repne
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scasb ! Look for the zero byte in s1
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dec edi ! Back one up (and clear 'Z' flag)
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push edi ! Save end of s1
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mov edi, 12(ebp) ! edi = string s2
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mov ecx, edx ! Maximum count
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repne
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scasb ! Look for the end of s2
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jne no0
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inc ecx ! Exclude null byte
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no0: sub edx, ecx ! Number of bytes in s2
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mov ecx, edx
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mov esi, 12(ebp) ! esi = string s2
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pop edi ! edi = end of string s1
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rep
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movsb ! Copy bytes
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stosb ! Add a terminating null
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mov eax, 8(ebp) ! Return s1
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pop edi
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pop esi
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pop ebp
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ret
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