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/*
* linux/arch/arm/lib/strncpy_from_user.S
*
* Copyright (C) 1995-2000 Russell King
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/errno.h>
.text
.align 5
/*
* Copy a string from user space to kernel space.
* r0 = dst, r1 = src, r2 = byte length
* returns the number of characters copied (strlen of copied string),
* -EFAULT on exception, or "len" if we fill the whole buffer
*/
ENTRY(__arch_strncpy_from_user)
save_lr
mov ip, r1
1: subs r2, r2, #1
USER( ldrplbt r3, [r1], #1)
bmi 2f
strb r3, [r0], #1
teq r3, #0
bne 1b
sub r1, r1, #1 @ take NUL character out of count
2: sub r0, r1, ip
restore_pc
.section .fixup,"ax"
.align 0
9001: mov r3, #0
strb r3, [r0, #0] @ null terminate
mov r0, #-EFAULT
restore_pc
.previous
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