1 files changed, 72 insertions, 0 deletions
diff --git a/libc/string/generic/strncmp.c b/libc/string/generic/strncmp.c
new file mode 100644
index 000000000..d9964a883
--- /dev/null
+++ b/libc/string/generic/strncmp.c
@@ -0,0 +1,72 @@
+/* Copyright (C) 1991, 1996, 1997, 2003 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"
+
+#undef strncmp
+
+/* Compare no more than N characters of S1 and S2,
+   returning less than, equal to or greater than zero
+   if S1 is lexicographically less than, equal to or
+   greater than S2.  */
+int
+strncmp (s1, s2, n)
+     const char *s1;
+     const char *s2;
+     size_t n;
+{
+  unsigned reg_char c1 = '\0';
+  unsigned reg_char c2 = '\0';
+
+  if (n >= 4)
+    {
+      size_t n4 = n >> 2;
+      do
+	{
+	  c1 = (unsigned char) *s1++;
+	  c2 = (unsigned char) *s2++;
+	  if (c1 == '\0' || c1 != c2)
+	    return c1 - c2;
+	  c1 = (unsigned char) *s1++;
+	  c2 = (unsigned char) *s2++;
+	  if (c1 == '\0' || c1 != c2)
+	    return c1 - c2;
+	  c1 = (unsigned char) *s1++;
+	  c2 = (unsigned char) *s2++;
+	  if (c1 == '\0' || c1 != c2)
+	    return c1 - c2;
+	  c1 = (unsigned char) *s1++;
+	  c2 = (unsigned char) *s2++;
+	  if (c1 == '\0' || c1 != c2)
+	    return c1 - c2;
+	} while (--n4 > 0);
+      n &= 3;
+    }
+
+  while (n > 0)
+    {
+      c1 = (unsigned char) *s1++;
+      c2 = (unsigned char) *s2++;
+      if (c1 == '\0' || c1 != c2)
+	return c1 - c2;
+      n--;
+    }
+
+  return c1 - c2;
+}