1/*
2 * Just like strncpy() except that if a fault occurs during copying,
3 * -EFAULT is returned.
4 *
5 * Inputs:
6 *	in0:	address of destination buffer
7 *	in1:	address of string to be copied
8 *	in2:	length of buffer in bytes
9 * Outputs:
10 *	r8:	-EFAULT in case of fault or number of bytes copied if no fault
11 *
12 * Copyright (C) 1998-2001 Hewlett-Packard Co
13 * Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com>
14 *
15 * 00/03/06 D. Mosberger Fixed to return proper return value (bug found by
16 *			 by Andreas Schwab <schwab@suse.de>).
17 */
18
19#include <asm/asmmacro.h>
20#include <asm/export.h>
21
22GLOBAL_ENTRY(__strncpy_from_user)
23	alloc r2=ar.pfs,3,0,0,0
24	mov r8=0
25	mov r9=in1
26	;;
27	add r10=in1,in2
28	cmp.eq p6,p0=r0,in2
29(p6)	br.ret.spnt.many rp
30
31	// XXX braindead copy loop---this needs to be optimized
32.Loop1:
33	EX(.Lexit, ld1 r8=[in1],1)
34	;;
35	EX(.Lexit, st1 [in0]=r8,1)
36	cmp.ne p6,p7=r8,r0
37	;;
38(p6)	cmp.ne.unc p8,p0=in1,r10
39(p8)	br.cond.dpnt.few .Loop1
40	;;
41(p6)	mov r8=in2		// buffer filled up---return buffer length
42(p7)	sub r8=in1,r9,1		// return string length (excluding NUL character)
43[.Lexit:]
44	br.ret.sptk.many rp
45END(__strncpy_from_user)
46EXPORT_SYMBOL(__strncpy_from_user)
47