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Diffstat (limited to 'sysdeps/generic/memcpy_chk.c')
-rw-r--r--sysdeps/generic/memcpy_chk.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/sysdeps/generic/memcpy_chk.c b/sysdeps/generic/memcpy_chk.c
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+++ b/sysdeps/generic/memcpy_chk.c
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+/* Copy memory to memory until the specified number of bytes
+ has been copied with error checking. Overlap is NOT handled correctly.
+ Copyright (C) 1991, 1997, 2003, 2004 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Torbjorn Granlund (tege@sics.se).
+
+ 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>
+#include <pagecopy.h>
+
+void *
+__memcpy_chk (dstpp, srcpp, len, dstlen)
+ void *dstpp;
+ const void *srcpp;
+ size_t len;
+ size_t dstlen;
+{
+ if (__builtin_expect (dstlen < len, 0))
+ __chk_fail ();
+
+ unsigned long int dstp = (long int) dstpp;
+ unsigned long int srcp = (long int) srcpp;
+
+ /* Copy from the beginning to the end. */
+
+ /* If there not too few bytes to copy, use word copy. */
+ if (len >= OP_T_THRES)
+ {
+ /* Copy just a few bytes to make DSTP aligned. */
+ len -= (-dstp) % OPSIZ;
+ BYTE_COPY_FWD (dstp, srcp, (-dstp) % OPSIZ);
+
+ /* Copy whole pages from SRCP to DSTP by virtual address manipulation,
+ as much as possible. */
+
+ PAGE_COPY_FWD_MAYBE (dstp, srcp, len, len);
+
+ /* Copy from SRCP to DSTP taking advantage of the known alignment of
+ DSTP. Number of bytes remaining is put in the third argument,
+ i.e. in LEN. This number may vary from machine to machine. */
+
+ WORD_COPY_FWD (dstp, srcp, len, len);
+
+ /* Fall out and copy the tail. */
+ }
+
+ /* There are just a few bytes to copy. Use byte memory operations. */
+ BYTE_COPY_FWD (dstp, srcp, len);
+
+ return dstpp;
+}