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/*
* linux/arch/arm/lib/strnlen_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
/* Prototype: unsigned long __arch_strnlen_user(const char *str, long n)
* Purpose : get length of a string in user memory
* Params : str - address of string in user memory
* Returns : length of string *including terminator*
* or zero on exception, or n + 1 if too long
*/
ENTRY(__arch_strnlen_user)
save_lr
mov r2, r0
1:
USER( ldrbt r3, [r0], #1)
teq r3, #0
beq 2f
subs r1, r1, #1
bne 1b
add r0, r0, #1
2: sub r0, r0, r2
restore_pc
.section .fixup,"ax"
.align 0
9001: mov r0, #0
restore_pc
.previous
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