From 0c83b1b6923ac28545d5956338f6aa31bfc91320 Mon Sep 17 00:00:00 2001
From: Sean Chittenden <sean@chittenden.org>
Date: Sat, 30 Jan 2016 15:47:58 -0800
Subject: [PATCH] Use rand.Int31n() vs unconditionally using modulus

---
 consul/client.go | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/consul/client.go b/consul/client.go
index 28bce77e8e..59a18c0e38 100644
--- a/consul/client.go
+++ b/consul/client.go
@@ -334,6 +334,7 @@ func (c *Client) localEvent(event serf.UserEvent) {
 func (c *Client) RPC(method string, args interface{}, reply interface{}) error {
 	// Check the last rpc time
 	now := time.Now()
+	var numConsulServers int
 	lastRPCTime := now.Sub(c.lastRPCTime)
 	var server *serverParts
 	if c.lastServer != nil && lastRPCTime < clientRPCConnMaxIdle {
@@ -345,13 +346,14 @@ func (c *Client) RPC(method string, args interface{}, reply interface{}) error {
 
 	// Bail if we can't find any servers
 	c.consulLock.RLock()
-	if len(c.consuls) == 0 {
+	numConsulServers = len(c.consuls)
+	if numConsulServers == 0 {
 		c.consulLock.RUnlock()
 		return structs.ErrNoServers
 	}
 
 	// Select a random addr
-	server = c.consuls[rand.Int31()%int32(len(c.consuls))]
+	server = c.consuls[rand.Int31n(int32(numConsulServers))]
 	c.consulLock.RUnlock()
 
 	// Forward to remote Consul