1*1da177e4SLinus Torvalds/* 2*1da177e4SLinus Torvalds * Just like strncpy() except that if a fault occurs during copying, 3*1da177e4SLinus Torvalds * -EFAULT is returned. 4*1da177e4SLinus Torvalds * 5*1da177e4SLinus Torvalds * Inputs: 6*1da177e4SLinus Torvalds * in0: address of destination buffer 7*1da177e4SLinus Torvalds * in1: address of string to be copied 8*1da177e4SLinus Torvalds * in2: length of buffer in bytes 9*1da177e4SLinus Torvalds * Outputs: 10*1da177e4SLinus Torvalds * r8: -EFAULT in case of fault or number of bytes copied if no fault 11*1da177e4SLinus Torvalds * 12*1da177e4SLinus Torvalds * Copyright (C) 1998-2001 Hewlett-Packard Co 13*1da177e4SLinus Torvalds * Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com> 14*1da177e4SLinus Torvalds * 15*1da177e4SLinus Torvalds * 00/03/06 D. Mosberger Fixed to return proper return value (bug found by 16*1da177e4SLinus Torvalds * by Andreas Schwab <schwab@suse.de>). 17*1da177e4SLinus Torvalds */ 18*1da177e4SLinus Torvalds 19*1da177e4SLinus Torvalds#include <asm/asmmacro.h> 20*1da177e4SLinus Torvalds 21*1da177e4SLinus TorvaldsGLOBAL_ENTRY(__strncpy_from_user) 22*1da177e4SLinus Torvalds alloc r2=ar.pfs,3,0,0,0 23*1da177e4SLinus Torvalds mov r8=0 24*1da177e4SLinus Torvalds mov r9=in1 25*1da177e4SLinus Torvalds ;; 26*1da177e4SLinus Torvalds add r10=in1,in2 27*1da177e4SLinus Torvalds cmp.eq p6,p0=r0,in2 28*1da177e4SLinus Torvalds(p6) br.ret.spnt.many rp 29*1da177e4SLinus Torvalds 30*1da177e4SLinus Torvalds // XXX braindead copy loop---this needs to be optimized 31*1da177e4SLinus Torvalds.Loop1: 32*1da177e4SLinus Torvalds EX(.Lexit, ld1 r8=[in1],1) 33*1da177e4SLinus Torvalds ;; 34*1da177e4SLinus Torvalds EX(.Lexit, st1 [in0]=r8,1) 35*1da177e4SLinus Torvalds cmp.ne p6,p7=r8,r0 36*1da177e4SLinus Torvalds ;; 37*1da177e4SLinus Torvalds(p6) cmp.ne.unc p8,p0=in1,r10 38*1da177e4SLinus Torvalds(p8) br.cond.dpnt.few .Loop1 39*1da177e4SLinus Torvalds ;; 40*1da177e4SLinus Torvalds(p6) mov r8=in2 // buffer filled up---return buffer length 41*1da177e4SLinus Torvalds(p7) sub r8=in1,r9,1 // return string length (excluding NUL character) 42*1da177e4SLinus Torvalds[.Lexit:] 43*1da177e4SLinus Torvalds br.ret.sptk.many rp 44*1da177e4SLinus TorvaldsEND(__strncpy_from_user) 45