From 6c8b51e172a67c8e575299ad493f1702a0608336 Mon Sep 17 00:00:00 2001
From: Donald Sharp <sharpd@cumulusnetworks.com>
Date: Thu, 20 Sep 2018 13:59:35 -0400
Subject: [PATCH] lib: Add a couple functions to nexthop_group.c

Add nexthop_group_copy and nexthop_group_add_sorted functions.

nexthop_group_copy -> Copy src nexthop_group into dst nexthop_group
nexthop_group_add_sorted -> Adds a new nexthop to the nexthop group
in a sorted manner.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
---
 lib/nexthop_group.c | 35 +++++++++++++++++++++++++++++++++++
 lib/nexthop_group.h |  4 ++++
 2 files changed, 39 insertions(+)

diff --git a/lib/nexthop_group.c b/lib/nexthop_group.c
index 10f610db37..d250e0e9b6 100644
--- a/lib/nexthop_group.c
+++ b/lib/nexthop_group.c
@@ -100,6 +100,12 @@ struct nexthop_group *nexthop_group_new(void)
 	return XCALLOC(MTYPE_NEXTHOP_GROUP, sizeof(struct nexthop_group));
 }
 
+void nexthop_group_copy(struct nexthop_group *to, struct nexthop_group *from)
+{
+	/* Copy everything, including recursive info */
+	copy_nexthops(&to->nexthop, from->nexthop, NULL);
+}
+
 void nexthop_group_delete(struct nexthop_group **nhg)
 {
 	XFREE(MTYPE_NEXTHOP_GROUP, *nhg);
@@ -119,6 +125,35 @@ void nexthop_add(struct nexthop **target, struct nexthop *nexthop)
 	nexthop->prev = last;
 }
 
+void nexthop_group_add_sorted(struct nexthop_group *nhg,
+			      struct nexthop *nexthop)
+{
+	struct nexthop *position, *prev;
+
+	for (position = nhg->nexthop, prev = NULL; position;
+	     prev = position, position = position->next) {
+		if (nexthop_cmp(position, nexthop) > 0) {
+			nexthop->next = position;
+			nexthop->prev = prev;
+
+			if (nexthop->prev)
+				nexthop->prev->next = nexthop;
+			else
+				nhg->nexthop = nexthop;
+
+			position->prev = nexthop;
+			return;
+		}
+	}
+
+	nexthop->prev = prev;
+	if (prev)
+		prev->next = nexthop;
+	else
+		nhg->nexthop = nexthop;
+
+}
+
 /* Delete nexthop from a nexthop list.  */
 void nexthop_del(struct nexthop_group *nhg, struct nexthop *nh)
 {
diff --git a/lib/nexthop_group.h b/lib/nexthop_group.h
index 5adf2db937..104e2051f5 100644
--- a/lib/nexthop_group.h
+++ b/lib/nexthop_group.h
@@ -43,6 +43,10 @@ struct nexthop_group *nexthop_group_new(void);
 void nexthop_group_delete(struct nexthop_group **nhg);
 
 void nexthop_add(struct nexthop **target, struct nexthop *nexthop);
+void nexthop_group_add_sorted(struct nexthop_group *nhg,
+			      struct nexthop *nexthop);
+void nexthop_group_copy(struct nexthop_group *to,
+			struct nexthop_group *from);
 void nexthop_del(struct nexthop_group *nhg, struct nexthop *nexthop);
 void copy_nexthops(struct nexthop **tnh, const struct nexthop *nh,
 		   struct nexthop *rparent);