1/* 2 * linux/arch/arm/lib/strnlen_user.S 3 * 4 * Copyright (C) 1995-2000 Russell King 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10#include <linux/linkage.h> 11#include <asm/assembler.h> 12#include <asm/errno.h> 13 14 .text 15 .align 5 16 17/* Prototype: unsigned long __strnlen_user(const char *str, long n) 18 * Purpose : get length of a string in user memory 19 * Params : str - address of string in user memory 20 * Returns : length of string *including terminator* 21 * or zero on exception, or n + 1 if too long 22 */ 23ENTRY(__strnlen_user) 24 mov r2, r0 251: 26 ldrusr r3, r0, 1 27 teq r3, #0 28 beq 2f 29 subs r1, r1, #1 30 bne 1b 31 add r0, r0, #1 322: sub r0, r0, r2 33 mov pc, lr 34ENDPROC(__strnlen_user) 35 36 .pushsection .fixup,"ax" 37 .align 0 389001: mov r0, #0 39 mov pc, lr 40 .popsection 41