2.5-18.1

1 files changed, 112 insertions, 0 deletions

diff --git a/string/memmove.c b/string/memmove.c
new file mode 100644
index 0000000000..16671f7bb5
--- /dev/null
+++ b/string/memmove.c
@@ -0,0 +1,112 @@
+/* Copy memory to memory until the specified number of bytes
+   has been copied.  Overlap is handled correctly.
+   Copyright (C) 1991, 1995, 1996, 1997, 2003 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>
+
+/* All this is so that bcopy.c can #include
+   this file after defining some things.  */
+#ifndef	a1
+#define	a1	dest	/* First arg is DEST.  */
+#define	a1const
+#define	a2	src	/* Second arg is SRC.  */
+#define	a2const	const
+#undef memmove
+#endif
+#if	!defined(RETURN) || !defined(rettype)
+#define	RETURN(s)	return (s)	/* Return DEST.  */
+#define	rettype		void *
+#endif
+
+
+rettype
+memmove (a1, a2, len)
+     a1const void *a1;
+     a2const void *a2;
+     size_t len;
+{
+  unsigned long int dstp = (long int) dest;
+  unsigned long int srcp = (long int) src;
+
+  /* This test makes the forward copying code be used whenever possible.
+     Reduces the working set.  */
+  if (dstp - srcp >= len)	/* *Unsigned* compare!  */
+    {
+      /* 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);
+    }
+  else
+    {
+      /* Copy from the end to the beginning.  */
+      srcp += len;
+      dstp += len;
+
+      /* 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_BWD (dstp, srcp, dstp % OPSIZ);
+
+	  /* 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_BWD (dstp, srcp, len, len);
+
+	  /* Fall out and copy the tail.  */
+	}
+
+      /* There are just a few bytes to copy.  Use byte memory operations.  */
+      BYTE_COPY_BWD (dstp, srcp, len);
+    }
+
+  RETURN (dest);
+}
+#ifndef memmove
+libc_hidden_builtin_def (memmove)
+#endif