10Sstevel@tonic-gate/* 20Sstevel@tonic-gate * CDDL HEADER START 30Sstevel@tonic-gate * 40Sstevel@tonic-gate * The contents of this file are subject to the terms of the 56812Sraf * Common Development and Distribution License (the "License"). 66812Sraf * You may not use this file except in compliance with the License. 70Sstevel@tonic-gate * 80Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 90Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing. 100Sstevel@tonic-gate * See the License for the specific language governing permissions 110Sstevel@tonic-gate * and limitations under the License. 120Sstevel@tonic-gate * 130Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each 140Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 150Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the 160Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying 170Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner] 180Sstevel@tonic-gate * 190Sstevel@tonic-gate * CDDL HEADER END 200Sstevel@tonic-gate */ 216812Sraf 220Sstevel@tonic-gate/* 236812Sraf * Copyright 2008 Sun Microsystems, Inc. All rights reserved. 240Sstevel@tonic-gate * Use is subject to license terms. 250Sstevel@tonic-gate */ 260Sstevel@tonic-gate 27*7298SMark.J.Nelson@Sun.COM .file "strlcpy.s" 280Sstevel@tonic-gate/* 290Sstevel@tonic-gate * The strlcpy() function copies at most dstsize-1 characters 300Sstevel@tonic-gate * (dstsize being the size of the string buffer dst) from src 310Sstevel@tonic-gate * to dst, truncating src if necessary. The result is always 320Sstevel@tonic-gate * null-terminated. The function returns strlen(src). Buffer 330Sstevel@tonic-gate * overflow can be checked as follows: 340Sstevel@tonic-gate * 350Sstevel@tonic-gate * if (strlcpy(dst, src, dstsize) >= dstsize) 360Sstevel@tonic-gate * return -1; 370Sstevel@tonic-gate */ 380Sstevel@tonic-gate 390Sstevel@tonic-gate#include <sys/asm_linkage.h> 400Sstevel@tonic-gate 410Sstevel@tonic-gate ! strlcpy implementation is similar to that of strcpy, except 420Sstevel@tonic-gate ! in this case, the maximum size of the detination must be 430Sstevel@tonic-gate ! tracked since it bounds our maximum copy size. However, 440Sstevel@tonic-gate ! we must still continue to check for zero since the routine 450Sstevel@tonic-gate ! is expected to null-terminate any string that is within 460Sstevel@tonic-gate ! the dest size bound. 470Sstevel@tonic-gate ! 480Sstevel@tonic-gate ! this method starts by checking for and arranging source alignment. 490Sstevel@tonic-gate ! Once this has occurred, we copy based upon destination alignment. 500Sstevel@tonic-gate ! This is either by word, halfword, or byte. As this occurs, we 510Sstevel@tonic-gate ! check for a zero-byte. If one is found, we branch to a method 520Sstevel@tonic-gate ! which checks for the exact location of a zero-byte within a 530Sstevel@tonic-gate ! larger word/half-word quantity. 540Sstevel@tonic-gate 550Sstevel@tonic-gate ENTRY(strlcpy) 560Sstevel@tonic-gate 570Sstevel@tonic-gate .align 32 580Sstevel@tonic-gate save %sp, -SA(WINDOWSIZE), %sp 590Sstevel@tonic-gate subcc %g0, %i2, %g4 ! n = -n or n == 0 ? 600Sstevel@tonic-gate bz,pn %icc, .getstrlen ! if 0 do nothing but strlen(src) 610Sstevel@tonic-gate add %i1, %i2, %i3 ! i3 = src + n 620Sstevel@tonic-gate andcc %i1, 3, %i4 ! word aligned? 630Sstevel@tonic-gate bz,pn %icc, .wordaligned 640Sstevel@tonic-gate add %i0, %i2, %i2 ! n = dst + n 650Sstevel@tonic-gate sub %i4, 4, %i4 ! bytes until src aligned 660Sstevel@tonic-gate 670Sstevel@tonic-gate.alignsrc: 680Sstevel@tonic-gate ldub [%i3 + %g4], %l1 ! l1 = src[] 690Sstevel@tonic-gate andcc %l1, 0xff, %g0 ! null byte reached? 700Sstevel@tonic-gate stub %l1, [%i2 + %g4] ! dst[] = src[] 710Sstevel@tonic-gate bz,a %icc, .done 720Sstevel@tonic-gate add %i2, %g4, %i2 ! get single dest ptr for strlen 730Sstevel@tonic-gate addcc %g4, 1, %g4 ! src++ dest++ n-- 740Sstevel@tonic-gate bz,pn %icc, .forcenullunalign ! n == 0, append null byte 750Sstevel@tonic-gate addcc %i4, 1, %i4 ! incr, check align 760Sstevel@tonic-gate bnz,a %icc, .alignsrc 770Sstevel@tonic-gate nop 780Sstevel@tonic-gate 790Sstevel@tonic-gate.wordaligned: 800Sstevel@tonic-gate sethi %hi(0x01010101), %i4 810Sstevel@tonic-gate add %i2, %g4, %l0 ! l0 = dest 820Sstevel@tonic-gate or %i4, %lo(0x01010101), %i4 830Sstevel@tonic-gate sub %i2, 4, %i2 ! pre-incr for in cpy loop 840Sstevel@tonic-gate andcc %l0, 3, %g1 ! word aligned? 850Sstevel@tonic-gate bnz %icc, .dstnotaligned 860Sstevel@tonic-gate sll %i4, 7, %i5 ! Mycroft part deux 870Sstevel@tonic-gate 880Sstevel@tonic-gate.storeword: 890Sstevel@tonic-gate ld [%i3 + %g4], %l1 ! l1 = src[] 900Sstevel@tonic-gate addcc %g4, 4, %g4 ! n += 4, src += 4, dst +=4 910Sstevel@tonic-gate bcs,pn %icc, .lastword 920Sstevel@tonic-gate andn %i5, %l1, %g1 ! ~word & 0x80808080 930Sstevel@tonic-gate sub %l1, %i4, %l0 ! word - 0x01010101 940Sstevel@tonic-gate andcc %l0, %g1, %g0 ! doit 950Sstevel@tonic-gate bz,a,pt %icc, .storeword ! if expr == 0, no zero byte 960Sstevel@tonic-gate st %l1, [%i2 + %g4] ! dst[] = src[] 970Sstevel@tonic-gate 980Sstevel@tonic-gate.zerobyte: 990Sstevel@tonic-gate add %i2, %g4, %i2 ! ptr to dest 1000Sstevel@tonic-gate srl %l1, 24, %g1 ! 1st byte 1010Sstevel@tonic-gate andcc %g1, 0xff, %g0 ! test for end 1020Sstevel@tonic-gate bz,pn %icc, .done 1030Sstevel@tonic-gate stb %g1, [%i2] ! store byte 1040Sstevel@tonic-gate add %i2, 1, %i2 ! dst ++ 1050Sstevel@tonic-gate srl %l1, 16, %g1 ! 2nd byte 1060Sstevel@tonic-gate andcc %g1, 0xff, %g0 ! zero byte ? 1070Sstevel@tonic-gate bz,pn %icc, .done 1080Sstevel@tonic-gate stb %g1, [%i2] ! store byte 1090Sstevel@tonic-gate add %i2, 1, %i2 ! dst ++ 1100Sstevel@tonic-gate srl %l1, 8, %g1 ! 3rd byte 1110Sstevel@tonic-gate andcc %g1, 0xff, %g0 ! zero byte ? 1120Sstevel@tonic-gate bz,pn %icc, .done 1130Sstevel@tonic-gate stb %g1, [%i2] ! store byte 1140Sstevel@tonic-gate stb %l1, [%i2 + 1] ! store last byte 1150Sstevel@tonic-gate add %i2, 1, %i2 ! dst ++ 1160Sstevel@tonic-gate 1170Sstevel@tonic-gate.done: 1180Sstevel@tonic-gate sub %i2, %i0, %i0 ! len = dst - orig dst 1190Sstevel@tonic-gate ret 1200Sstevel@tonic-gate restore %i0, %g0, %o0 1210Sstevel@tonic-gate 1220Sstevel@tonic-gate.lastword: 1230Sstevel@tonic-gate add %i2, %g4, %i2 1240Sstevel@tonic-gate sub %g4, 4, %g4 ! undo pre-incr 1250Sstevel@tonic-gate add %i3, %g4, %i3 1260Sstevel@tonic-gate 1270Sstevel@tonic-gate srl %l1, 24, %g1 ! 1st byte 1280Sstevel@tonic-gate andcc %g1, 0xff, %g0 ! zero byte? 1290Sstevel@tonic-gate bz,pn %icc, .done 1300Sstevel@tonic-gate stb %g1, [%i2] ! store byte 1310Sstevel@tonic-gate inccc %g4 ! n-- 1320Sstevel@tonic-gate bz .forcenull 1330Sstevel@tonic-gate srl %l1, 16, %g1 ! 2nd byte 1340Sstevel@tonic-gate add %i2, 1, %i2 ! dst++ 1350Sstevel@tonic-gate andcc %g1, 0xff, %g0 ! zero? 1360Sstevel@tonic-gate bz,pn %icc, .done 1370Sstevel@tonic-gate stb %g1, [%i2] ! store 1380Sstevel@tonic-gate inccc %g4 1390Sstevel@tonic-gate bz .forcenull 1400Sstevel@tonic-gate srl %l1, 8, %g1 ! 3rd byte 1410Sstevel@tonic-gate add %i2, 1, %i2 ! dst++ 1420Sstevel@tonic-gate andcc %g1, 0xff, %g0 ! zero? 1430Sstevel@tonic-gate bz,pn %icc, .done 1440Sstevel@tonic-gate stb %g1, [%i2] ! store 1450Sstevel@tonic-gate inccc %g4 ! n-- 1460Sstevel@tonic-gate bz .forcenull 1470Sstevel@tonic-gate andcc %l1, 0xff, %g0 ! zero? 1480Sstevel@tonic-gate add %i2, 1, %i2 ! dst++ 1490Sstevel@tonic-gate bz,pn %ncc, .done 1500Sstevel@tonic-gate stb %l1, [%i2] 1510Sstevel@tonic-gate 1520Sstevel@tonic-gate.forcenull: 1530Sstevel@tonic-gate stb %g0, [%i2] 1540Sstevel@tonic-gate 1550Sstevel@tonic-gate.searchword: 1560Sstevel@tonic-gate ld [%i3], %l1 1570Sstevel@tonic-gate.searchword2: 1580Sstevel@tonic-gate andn %i5, %l1, %g1 ! word & 0x80808080 1590Sstevel@tonic-gate sub %l1, %i4, %l0 ! word - 0x01010101 1600Sstevel@tonic-gate andcc %l0, %g1, %g0 ! do it 1610Sstevel@tonic-gate bz,a,pt %icc, .searchword 1620Sstevel@tonic-gate add %i3, 4, %i3 ! src += 4 1630Sstevel@tonic-gate 1640Sstevel@tonic-gate mov 0xff, %i5 1650Sstevel@tonic-gate sll %i5, 24, %i5 ! mask 1st byte = 0xff000000 1660Sstevel@tonic-gate.searchbyte: 1670Sstevel@tonic-gate andcc %l1, %i5, %g0 ! cur byte 0? 1680Sstevel@tonic-gate srl %i5, 8, %i5 ! mask next byte 1690Sstevel@tonic-gate bnz,a %icc, .searchbyte ! cur !=0 continue 1700Sstevel@tonic-gate add %i3, 1, %i3 1710Sstevel@tonic-gate 1720Sstevel@tonic-gate.endfound: 1730Sstevel@tonic-gate sub %i3, %i1, %i0 ! len = src - orig src 1740Sstevel@tonic-gate ret 1750Sstevel@tonic-gate restore %i0, %g0, %o0 1760Sstevel@tonic-gate nop 1770Sstevel@tonic-gate 1780Sstevel@tonic-gate.dstnotaligned: 1790Sstevel@tonic-gate cmp %g1, 2 ! halfword aligned? 1800Sstevel@tonic-gate be .storehalfword2 1810Sstevel@tonic-gate .empty 1820Sstevel@tonic-gate.storebyte: 1830Sstevel@tonic-gate ld [%i3 + %g4], %l1 ! load src word 1840Sstevel@tonic-gate addcc %g4, 4, %g4 ! src +=4 dst +=4 1850Sstevel@tonic-gate bcs,pn %icc, .lastword 1860Sstevel@tonic-gate andn %i5, %l1, %g1 ! ~x & 0x80808080 1870Sstevel@tonic-gate sub %l1, %i4, %l0 ! x - 0x01010101 1880Sstevel@tonic-gate andcc %l0, %g1, %g0 ! get your Mycroft on 1890Sstevel@tonic-gate bnz,pn %icc, .zerobyte ! non-zero, we have zero byte 1900Sstevel@tonic-gate add %i2, %g4, %l0 ! dst in ptr form 1910Sstevel@tonic-gate srl %l1, 24, %g1 ! get 1st byte, then be hw aligned 1920Sstevel@tonic-gate stb %g1, [%l0] 1930Sstevel@tonic-gate srl %l1, 8, %g1 ! 2nd & 3rd bytes 1940Sstevel@tonic-gate sth %g1, [%l0 + 1] 1950Sstevel@tonic-gate ba .storebyte 1960Sstevel@tonic-gate stb %l1, [%l0 + 3] ! store 4th byte 1970Sstevel@tonic-gate 1980Sstevel@tonic-gate.storehalfword: 1990Sstevel@tonic-gate ld [%i3 + %g4], %l1 ! src word 2000Sstevel@tonic-gate.storehalfword2: 2010Sstevel@tonic-gate addcc %g4, 4, %g4 ! src += 4 dst += 4 2020Sstevel@tonic-gate bcs,pn %icc, .lastword 2030Sstevel@tonic-gate andn %i5, %l1, %g1 ! ~x & 0x80808080 2040Sstevel@tonic-gate sub %l1, %i4, %l0 ! x - 0x01010101 2050Sstevel@tonic-gate andcc %l0, %g1, %g0 ! Mycroft again... 2060Sstevel@tonic-gate bnz,pn %icc, .zerobyte ! non-zer, we have zero byte 2070Sstevel@tonic-gate add %i2, %g4, %l0 ! dst in ptr form 2080Sstevel@tonic-gate srl %l1, 16, %g1 ! first two bytes 2090Sstevel@tonic-gate sth %g1, [%l0] 2100Sstevel@tonic-gate ba .storehalfword 2110Sstevel@tonic-gate sth %l1, [%l0 + 2] 2120Sstevel@tonic-gate 2130Sstevel@tonic-gate.forcenullunalign: 2140Sstevel@tonic-gate add %i2, %g4, %i2 ! single dst ptr 2150Sstevel@tonic-gate stb %g0, [%i2 - 1] ! store terminating null byte 2160Sstevel@tonic-gate 2170Sstevel@tonic-gate.getstrlen: 2180Sstevel@tonic-gate sethi %hi(0x01010101), %i4 ! Mycroft... 2190Sstevel@tonic-gate or %i4, %lo(0x01010101), %i4 2200Sstevel@tonic-gate sll %i4, 7, %i5 2210Sstevel@tonic-gate 2220Sstevel@tonic-gate.getstrlenloop: 2230Sstevel@tonic-gate andcc %i3, 3, %g0 ! word aligned? 2240Sstevel@tonic-gate bz,a,pn %icc, .searchword2 ! search word at a time 2250Sstevel@tonic-gate ld [%i3], %l1 ! src word 2260Sstevel@tonic-gate ldub [%i3], %l1 ! src byte 2270Sstevel@tonic-gate andcc %l1, 0xff, %g0 ! end of src? 2280Sstevel@tonic-gate bnz,a %icc, .getstrlenloop 2290Sstevel@tonic-gate add %i3, 1, %i3 ! src ++ 2300Sstevel@tonic-gate sub %i3, %i1, %i0 ! len = src - orig src 2310Sstevel@tonic-gate ret 2320Sstevel@tonic-gate restore %i0, %g0, %o0 2330Sstevel@tonic-gate SET_SIZE(strlcpy) 234