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41 lines
904 B
41 lines
904 B
20 years ago
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/*
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* linux/arch/arm/lib/strnlen_user.S
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*
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* Copyright (C) 1995-2000 Russell King
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*/
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#include <linux/linkage.h>
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#include <asm/assembler.h>
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#include <asm/errno.h>
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.text
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.align 5
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/* Prototype: unsigned long __arch_strnlen_user(const char *str, long n)
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* Purpose : get length of a string in user memory
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* Params : str - address of string in user memory
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* Returns : length of string *including terminator*
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* or zero on exception, or n + 1 if too long
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*/
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ENTRY(__arch_strnlen_user)
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save_lr
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mov r2, r0
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1:
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USER( ldrbt r3, [r0], #1)
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teq r3, #0
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beq 2f
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subs r1, r1, #1
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bne 1b
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add r0, r0, #1
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2: sub r0, r0, r2
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restore_pc
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.section .fixup,"ax"
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.align 0
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9001: mov r0, #0
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restore_pc
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.previous
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