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-rw-r--r--string/stpncpy.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/string/stpncpy.c b/string/stpncpy.c
new file mode 100644
index 0000000000..164d0f1747
--- /dev/null
+++ b/string/stpncpy.c
@@ -0,0 +1,100 @@
+/* Copyright (C) 1993, 1995, 1996, 1997, 2002 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.  */
+
+/* This is almost copied from strncpy.c, written by Torbjorn Granlund.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#ifdef _LIBC
+# include <string.h>
+#else
+# include <sys/types.h>
+#endif
+
+#ifndef weak_alias
+# define __stpncpy stpncpy
+#endif
+
+/* Copy no more than N characters of SRC to DEST, returning the address of
+   the terminating '\0' in DEST, if any, or else DEST + N.  */
+char *
+__stpncpy (dest, src, n)
+     char *dest;
+     const char *src;
+     size_t n;
+{
+  char c;
+  char *s = 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 -= dest - s;
+      goto zero_fill;
+    }
+
+ last_chars:
+  n &= 3;
+  if (n == 0)
+    return dest;
+
+  for (;;)
+    {
+      c = *src++;
+      --n;
+      *dest++ = c;
+      if (c == '\0')
+	break;
+      if (n == 0)
+	return dest;
+    }
+
+ zero_fill:
+  while (n-- > 0)
+    dest[n] = '\0';
+
+  return dest - 1;
+}
+#ifdef weak_alias
+libc_hidden_def (__stpncpy)
+weak_alias (__stpncpy, stpncpy)
+#endif