--- a/src/common/CMakeLists.txt	Mon Jun 29 10:20:21 2015 -0400
+++ b/src/common/CMakeLists.txt	Mon Jun 29 10:27:03 2015 -0400
@@ -21,6 +21,7 @@
 #
 
 add_library(nomad_common SHARED
+	oid.c
 	uuid.c
 	vclock.c
 )

--- a/src/common/include/nomad/types.h	Mon Jun 29 10:20:21 2015 -0400
+++ b/src/common/include/nomad/types.h	Mon Jun 29 10:27:03 2015 -0400
@@ -29,9 +29,9 @@
 
 /* object id */
 struct noid {
-	uint32_t ds;
-	uint32_t _reserved; /* must be zero */
-	uint64_t uniq;
+	uint32_t ds;		/* dataset id */
+	uint32_t _reserved;	/* must be zero */
+	uint64_t uniq;		/* dataset-local id */
 };
 
 /* version vector */
@@ -51,6 +51,8 @@
 	uint8_t raw[16];
 };
 
+extern int noid_cmp(const struct noid *n1, const struct noid *n2);
+
 extern struct nvclock *nvclock_alloc(uint16_t nodes);
 extern void nvclock_free(struct nvclock *clock);
 

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/common/oid.c	Mon Jun 29 10:27:03 2015 -0400
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2015 Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <nomad/types.h>
+
+int noid_cmp(const struct noid *n1, const struct noid *n2)
+{
+	if (n1->ds < n2->ds)
+		return -1;
+	if (n1->ds > n2->ds)
+		return 1;
+
+	if (n1->uniq < n2->uniq)
+		return -1;
+	if (n1->uniq > n2->uniq)
+		return 1;
+
+	return 0;
+}