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Diffstat (limited to 'sysdeps/generic/memset_chk.c')
-rw-r--r-- | sysdeps/generic/memset_chk.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/sysdeps/generic/memset_chk.c b/sysdeps/generic/memset_chk.c new file mode 100644 index 0000000..c311914 --- /dev/null +++ b/sysdeps/generic/memset_chk.c @@ -0,0 +1,92 @@ +/* Copyright (C) 1991, 1997, 2003, 2004 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <string.h> +#include <memcopy.h> + +void * +__memset_chk (dstpp, c, len, dstlen) + void *dstpp; + int c; + size_t len; + size_t dstlen; +{ + if (__builtin_expect (dstlen < len, 0)) + __chk_fail (); + + long int dstp = (long int) dstpp; + + if (len >= 8) + { + size_t xlen; + op_t cccc; + + cccc = (unsigned char) c; + cccc |= cccc << 8; + cccc |= cccc << 16; + if (OPSIZ > 4) + /* Do the shift in two steps to avoid warning if long has 32 bits. */ + cccc |= (cccc << 16) << 16; + + /* There are at least some bytes to set. + No need to test for LEN == 0 in this alignment loop. */ + while (dstp % OPSIZ != 0) + { + ((byte *) dstp)[0] = c; + dstp += 1; + len -= 1; + } + + /* Write 8 `op_t' per iteration until less than 8 `op_t' remain. */ + xlen = len / (OPSIZ * 8); + while (xlen > 0) + { + ((op_t *) dstp)[0] = cccc; + ((op_t *) dstp)[1] = cccc; + ((op_t *) dstp)[2] = cccc; + ((op_t *) dstp)[3] = cccc; + ((op_t *) dstp)[4] = cccc; + ((op_t *) dstp)[5] = cccc; + ((op_t *) dstp)[6] = cccc; + ((op_t *) dstp)[7] = cccc; + dstp += 8 * OPSIZ; + xlen -= 1; + } + len %= OPSIZ * 8; + + /* Write 1 `op_t' per iteration until less than OPSIZ bytes remain. */ + xlen = len / OPSIZ; + while (xlen > 0) + { + ((op_t *) dstp)[0] = cccc; + dstp += OPSIZ; + xlen -= 1; + } + len %= OPSIZ; + } + + /* Write the last few bytes. */ + while (len > 0) + { + ((byte *) dstp)[0] = c; + dstp += 1; + len -= 1; + } + + return dstpp; +} |