43 lines
966 B
ArmAsm
43 lines
966 B
ArmAsm
|
/*
|
||
|
|
* linux/arch/unicore32/lib/strnlen_user.S
|
||
|
|
*
|
||
|
|
* Code specific to PKUnity SoC and UniCore ISA
|
||
|
|
*
|
||
|
|
* Copyright (C) 2001-2010 GUAN Xue-tao
|
||
|
|
*
|
||
|
|
* 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 __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(__strnlen_user)
|
||
|
|
mov r2, r0
|
||
|
|
1:
|
||
|
|
ldrusr r3, r0, 1
|
||
|
|
cxor.a r3, #0
|
||
|
|
beq 2f
|
||
|
|
sub.a r1, r1, #1
|
||
|
|
bne 1b
|
||
|
|
add r0, r0, #1
|
||
|
|
2: sub r0, r0, r2
|
||
|
|
mov pc, lr
|
||
|
|
ENDPROC(__strnlen_user)
|
||
|
|
|
||
|
|
.pushsection .fixup,"ax"
|
||
|
|
.align 0
|
||
|
|
9001: mov r0, #0
|
||
|
|
mov pc, lr
|
||
|
|
.popsection
|