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 21GLOBAL_ENTRY(__strncpy_from_user) 22 alloc r2=ar.pfs,3,0,0,0 23 mov r8=0 24 mov r9=in1 25 ;; 26 add r10=in1,in2 27 cmp.eq p6,p0=r0,in2 28(p6) br.ret.spnt.many rp 29 30 // XXX braindead copy loop---this needs to be optimized 31.Loop1: 32 EX(.Lexit, ld1 r8=[in1],1) 33 ;; 34 EX(.Lexit, st1 [in0]=r8,1) 35 cmp.ne p6,p7=r8,r0 36 ;; 37(p6) cmp.ne.unc p8,p0=in1,r10 38(p8) br.cond.dpnt.few .Loop1 39 ;; 40(p6) mov r8=in2 // buffer filled up---return buffer length 41(p7) sub r8=in1,r9,1 // return string length (excluding NUL character) 42[.Lexit:] 43 br.ret.sptk.many rp 44END(__strncpy_from_user) 45