11da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds/* 21da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Just like strncpy() except that if a fault occurs during copying, 31da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * -EFAULT is returned. 41da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 51da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Inputs: 61da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * in0: address of destination buffer 71da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * in1: address of string to be copied 81da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * in2: length of buffer in bytes 91da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Outputs: 101da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * r8: -EFAULT in case of fault or number of bytes copied if no fault 111da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 121da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Copyright (C) 1998-2001 Hewlett-Packard Co 131da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * Copyright (C) 1998-2001 David Mosberger-Tang <davidm@hpl.hp.com> 141da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 151da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * 00/03/06 D. Mosberger Fixed to return proper return value (bug found by 161da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds * by Andreas Schwab <schwab@suse.de>). 171da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds */ 181da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 191da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds#include <asm/asmmacro.h> 201da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 211da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus TorvaldsGLOBAL_ENTRY(__strncpy_from_user) 221da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds alloc r2=ar.pfs,3,0,0,0 231da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds mov r8=0 241da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds mov r9=in1 251da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ;; 261da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds add r10=in1,in2 271da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds cmp.eq p6,p0=r0,in2 281da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds(p6) br.ret.spnt.many rp 291da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds 301da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds // XXX braindead copy loop---this needs to be optimized 311da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds.Loop1: 321da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds EX(.Lexit, ld1 r8=[in1],1) 331da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ;; 341da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds EX(.Lexit, st1 [in0]=r8,1) 351da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds cmp.ne p6,p7=r8,r0 361da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ;; 371da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds(p6) cmp.ne.unc p8,p0=in1,r10 381da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds(p8) br.cond.dpnt.few .Loop1 391da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds ;; 401da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds(p6) mov r8=in2 // buffer filled up---return buffer length 411da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds(p7) sub r8=in1,r9,1 // return string length (excluding NUL character) 421da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds[.Lexit:] 431da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus Torvalds br.ret.sptk.many rp 441da177e4c3f41524e886b7f1b8a0c1fc7321cacLinus TorvaldsEND(__strncpy_from_user) 45