| lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* Copyright (C) 1991, 1997, 2003 Free Software Foundation, Inc. |
| 2 | This file is part of the GNU C Library. |
| 3 | |
| 4 | The GNU C Library is free software; you can redistribute it and/or |
| 5 | modify it under the terms of the GNU Lesser General Public |
| 6 | License as published by the Free Software Foundation; either |
| 7 | version 2.1 of the License, or (at your option) any later version. |
| 8 | |
| 9 | The GNU C Library is distributed in the hope that it will be useful, |
| 10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | Lesser General Public License for more details. |
| 13 | |
| 14 | You should have received a copy of the GNU Lesser General Public |
| 15 | License along with the GNU C Library; if not, write to the Free |
| 16 | Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 17 | 02111-1307 USA. */ |
| 18 | |
| 19 | #include <string.h> |
| 20 | #include "memcopy.h" |
| 21 | |
| 22 | void *memset (void *dstpp, int c, size_t len) |
| 23 | { |
| 24 | long int dstp = (long int) dstpp; |
| 25 | |
| 26 | if (len >= 8) |
| 27 | { |
| 28 | size_t xlen; |
| 29 | op_t cccc; |
| 30 | |
| 31 | cccc = (unsigned char) c; |
| 32 | cccc |= cccc << 8; |
| 33 | cccc |= cccc << 16; |
| 34 | if (OPSIZ > 4) |
| 35 | /* Do the shift in two steps to avoid warning if long has 32 bits. */ |
| 36 | cccc |= (cccc << 16) << 16; |
| 37 | |
| 38 | /* There are at least some bytes to set. |
| 39 | No need to test for LEN == 0 in this alignment loop. */ |
| 40 | while (dstp % OPSIZ != 0) |
| 41 | { |
| 42 | ((byte *) dstp)[0] = c; |
| 43 | dstp += 1; |
| 44 | len -= 1; |
| 45 | } |
| 46 | |
| 47 | /* Write 8 `op_t' per iteration until less than 8 `op_t' remain. */ |
| 48 | xlen = len / (OPSIZ * 8); |
| 49 | while (xlen > 0) |
| 50 | { |
| 51 | ((op_t *) dstp)[0] = cccc; |
| 52 | ((op_t *) dstp)[1] = cccc; |
| 53 | ((op_t *) dstp)[2] = cccc; |
| 54 | ((op_t *) dstp)[3] = cccc; |
| 55 | ((op_t *) dstp)[4] = cccc; |
| 56 | ((op_t *) dstp)[5] = cccc; |
| 57 | ((op_t *) dstp)[6] = cccc; |
| 58 | ((op_t *) dstp)[7] = cccc; |
| 59 | dstp += 8 * OPSIZ; |
| 60 | xlen -= 1; |
| 61 | } |
| 62 | len %= OPSIZ * 8; |
| 63 | |
| 64 | /* Write 1 `op_t' per iteration until less than OPSIZ bytes remain. */ |
| 65 | xlen = len / OPSIZ; |
| 66 | while (xlen > 0) |
| 67 | { |
| 68 | ((op_t *) dstp)[0] = cccc; |
| 69 | dstp += OPSIZ; |
| 70 | xlen -= 1; |
| 71 | } |
| 72 | len %= OPSIZ; |
| 73 | } |
| 74 | |
| 75 | /* Write the last few bytes. */ |
| 76 | while (len > 0) |
| 77 | { |
| 78 | ((byte *) dstp)[0] = c; |
| 79 | dstp += 1; |
| 80 | len -= 1; |
| 81 | } |
| 82 | |
| 83 | return dstpp; |
| 84 | } |
| 85 | libc_hidden_weak(memset) |