1/* 2 * String handling functions for PowerPC. 3 * 4 * Copyright (C) 1996 Paul Mackerras. 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11#include <asm/processor.h> 12#include <asm/errno.h> 13#include <asm/ppc_asm.h> 14 15 .section __ex_table,"a" 16#ifdef CONFIG_PPC64 17 .align 3 18#define EXTBL .llong 19#else 20 .align 2 21#define EXTBL .long 22#endif 23 .text 24 25_GLOBAL(strcpy) 26 addi r5,r3,-1 27 addi r4,r4,-1 281: lbzu r0,1(r4) 29 cmpwi 0,r0,0 30 stbu r0,1(r5) 31 bne 1b 32 blr 33 34/* This clears out any unused part of the destination buffer, 35 just as the libc version does. -- paulus */ 36_GLOBAL(strncpy) 37 cmpwi 0,r5,0 38 beqlr 39 mtctr r5 40 addi r6,r3,-1 41 addi r4,r4,-1 421: lbzu r0,1(r4) 43 cmpwi 0,r0,0 44 stbu r0,1(r6) 45 bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */ 46 bnelr /* if we didn't hit a null char, we're done */ 47 mfctr r5 48 cmpwi 0,r5,0 /* any space left in destination buffer? */ 49 beqlr /* we know r0 == 0 here */ 502: stbu r0,1(r6) /* clear it out if so */ 51 bdnz 2b 52 blr 53 54_GLOBAL(strcat) 55 addi r5,r3,-1 56 addi r4,r4,-1 571: lbzu r0,1(r5) 58 cmpwi 0,r0,0 59 bne 1b 60 addi r5,r5,-1 611: lbzu r0,1(r4) 62 cmpwi 0,r0,0 63 stbu r0,1(r5) 64 bne 1b 65 blr 66 67_GLOBAL(strcmp) 68 addi r5,r3,-1 69 addi r4,r4,-1 701: lbzu r3,1(r5) 71 cmpwi 1,r3,0 72 lbzu r0,1(r4) 73 subf. r3,r0,r3 74 beqlr 1 75 beq 1b 76 blr 77 78_GLOBAL(strncmp) 79 PPC_LCMPI r5,0 80 beqlr 81 mtctr r5 82 addi r5,r3,-1 83 addi r4,r4,-1 841: lbzu r3,1(r5) 85 cmpwi 1,r3,0 86 lbzu r0,1(r4) 87 subf. r3,r0,r3 88 beqlr 1 89 bdnzt eq,1b 90 blr 91 92_GLOBAL(strlen) 93 addi r4,r3,-1 941: lbzu r0,1(r4) 95 cmpwi 0,r0,0 96 bne 1b 97 subf r3,r3,r4 98 blr 99 100_GLOBAL(memcmp) 101 cmpwi 0,r5,0 102 ble- 2f 103 mtctr r5 104 addi r6,r3,-1 105 addi r4,r4,-1 1061: lbzu r3,1(r6) 107 lbzu r0,1(r4) 108 subf. r3,r0,r3 109 bdnzt 2,1b 110 blr 1112: li r3,0 112 blr 113 114_GLOBAL(memchr) 115 cmpwi 0,r5,0 116 ble- 2f 117 mtctr r5 118 addi r3,r3,-1 1191: lbzu r0,1(r3) 120 cmpw 0,r0,r4 121 bdnzf 2,1b 122 beqlr 1232: li r3,0 124 blr 125 126_GLOBAL(__clear_user) 127 addi r6,r3,-4 128 li r3,0 129 li r5,0 130 cmplwi 0,r4,4 131 blt 7f 132 /* clear a single word */ 13311: stwu r5,4(r6) 134 beqlr 135 /* clear word sized chunks */ 136 andi. r0,r6,3 137 add r4,r0,r4 138 subf r6,r0,r6 139 srwi r0,r4,2 140 andi. r4,r4,3 141 mtctr r0 142 bdz 7f 1431: stwu r5,4(r6) 144 bdnz 1b 145 /* clear byte sized chunks */ 1467: cmpwi 0,r4,0 147 beqlr 148 mtctr r4 149 addi r6,r6,3 1508: stbu r5,1(r6) 151 bdnz 8b 152 blr 15390: mr r3,r4 154 blr 15591: mfctr r3 156 slwi r3,r3,2 157 add r3,r3,r4 158 blr 15992: mfctr r3 160 blr 161 162 .section __ex_table,"a" 163 EXTBL 11b,90b 164 EXTBL 1b,91b 165 EXTBL 8b,92b 166 .text 167 168_GLOBAL(__strncpy_from_user) 169 addi r6,r3,-1 170 addi r4,r4,-1 171 cmpwi 0,r5,0 172 beq 2f 173 mtctr r5 1741: lbzu r0,1(r4) 175 cmpwi 0,r0,0 176 stbu r0,1(r6) 177 bdnzf 2,1b /* dec ctr, branch if ctr != 0 && !cr0.eq */ 178 beq 3f 1792: addi r6,r6,1 1803: subf r3,r3,r6 181 blr 18299: li r3,-EFAULT 183 blr 184 185 .section __ex_table,"a" 186 EXTBL 1b,99b 187 .text 188 189/* r3 = str, r4 = len (> 0), r5 = top (highest addr) */ 190_GLOBAL(__strnlen_user) 191 addi r7,r3,-1 192 subf r6,r7,r5 /* top+1 - str */ 193 cmplw 0,r4,r6 194 bge 0f 195 mr r6,r4 1960: mtctr r6 /* ctr = min(len, top - str) */ 1971: lbzu r0,1(r7) /* get next byte */ 198 cmpwi 0,r0,0 199 bdnzf 2,1b /* loop if --ctr != 0 && byte != 0 */ 200 addi r7,r7,1 201 subf r3,r3,r7 /* number of bytes we have looked at */ 202 beqlr /* return if we found a 0 byte */ 203 cmpw 0,r3,r4 /* did we look at all len bytes? */ 204 blt 99f /* if not, must have hit top */ 205 addi r3,r4,1 /* return len + 1 to indicate no null found */ 206 blr 20799: li r3,0 /* bad address, return 0 */ 208 blr 209 210 .section __ex_table,"a" 211 EXTBL 1b,99b 212