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-rw-r--r--sysdeps/generic/stpncpy.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/sysdeps/generic/stpncpy.c b/sysdeps/generic/stpncpy.c
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+++ b/sysdeps/generic/stpncpy.c
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+/* Copyright (C) 1993, 1995 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 Library General Public License as
+published by the Free Software Foundation; either version 2 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
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+/* This is almost copied from strncpy.c, written by Torbjorn Granlund.  */
+
+#include <ansidecl.h>
+#include <string.h>
+#include <memcopy.h>
+
+
+/* Copy no more than N characters of SRC to DEST, returning the address of
+   the last character written into DEST.  */
+char *
+DEFUN(__stpncpy, (dest, src, n), char *dest AND CONST char *src AND size_t n)
+{
+  reg_char c;
+  char *s = dest;
+
+  --dest;
+
+  if (n >= 4)
+    {
+      size_t n4 = n >> 2;
+
+      for (;;)
+	{
+	  c = *src++;
+	  *++dest = c;
+	  if (c == '\0')
+	    break;
+	  c = *src++;
+	  *++dest = c;
+	  if (c == '\0')
+	    break;
+	  c = *src++;
+	  *++dest = c;
+	  if (c == '\0')
+	    break;
+	  c = *src++;
+	  *++dest = c;
+	  if (c == '\0')
+	    break;
+	  if (--n4 == 0)
+	    goto last_chars;
+	}
+      n = n - (dest - s) - 1;
+      if (n == 0)
+	return dest;
+      goto zero_fill;
+    }
+
+ last_chars:
+  n &= 3;
+  if (n == 0)
+    return s;
+
+  do
+    {
+      c = *src++;
+      *++dest = c;
+      if (--n == 0)
+	return dest;
+    }
+  while (c != '\0');
+
+ zero_fill:
+  do
+    *++dest = '\0';
+  while (--n > 0);
+
+  return dest;
+}
+
+weak_alias (__stpncpy, stpncpy)