1 files changed, 51 insertions, 0 deletions
diff --git a/sys/sys/_pctrie.h b/sys/sys/_pctrie.h
new file mode 100644
index 0000000..45f69b2
--- /dev/null
+++ b/sys/sys/_pctrie.h
@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2013 EMC Corp.
+ * Copyright (c) 2011 Jeffrey Roberson <jeff@freebsd.org>
+ * Copyright (c) 2008 Mayur Shardul <mayur.shardul@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef __SYS_PCTRIE_H_
+#define __SYS_PCTRIE_H_
+
+/*
+ * Radix tree root.
+ */
+struct pctrie {
+	uintptr_t	pt_root;
+};
+
+#ifdef _KERNEL
+
+static __inline boolean_t
+pctrie_is_empty(struct pctrie *ptree)
+{
+
+	return (ptree->pt_root == 0);
+}
+
+#endif /* _KERNEL */
+#endif /* !__SYS_PCTRIE_H_ */