From 3db825fde4f8af8fd3ba56438b4af3b58c1dbb04 Mon Sep 17 00:00:00 2001
From: antirez <antirez@gmail.com>
Date: Fri, 29 Nov 2013 16:17:05 +0100
Subject: [PATCH] Cluster: some code about clusterHandleSlaveFailover()
 marginally improved.

80 cols friendly, some minor change to the code to make it simpler.
---
 src/cluster.c | 24 +++++++++++++-----------
 src/cluster.h |  4 ++--
 2 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/src/cluster.c b/src/cluster.c
index 2f26100e..55d0e897 100644
--- a/src/cluster.c
+++ b/src/cluster.c
@@ -1681,7 +1681,8 @@ void clusterSendFailoverAuthIfNeeded(clusterNode *node, clusterMsg *request) {
 
     /* IF we are not a master serving at least 1 slot, we don't have the
      * right to vote, as the cluster size in Redis Cluster is the number
-     * of masters serving at least one slot, and quorum is the cluster size + 1 */
+     * of masters serving at least one slot, and quorum is the cluster
+     * size + 1 */
     if (!(server.cluster->myself->flags & REDIS_NODE_MASTER)) return;
     if (server.cluster->myself->numslots == 0) return;
 
@@ -1702,9 +1703,9 @@ void clusterSendFailoverAuthIfNeeded(clusterNode *node, clusterMsg *request) {
     if (mstime() - node->slaveof->voted_time < server.cluster_node_timeout * 2)
         return;
 
-    /* The slave requesting the vote must have a configEpoch for the claimed slots
-     * that is >= the one of the masters currently serving the same slots in the
-     * current configuration. */
+    /* The slave requesting the vote must have a configEpoch for the claimed
+     * slots that is >= the one of the masters currently serving the same
+     * slots in the current configuration. */
     for (j = 0; j < REDIS_CLUSTER_SLOTS; j++) {
         if (bitmapTestBit(claimed_slots, j) == 0) continue;
         if (server.cluster->slots[j] == NULL ||
@@ -1735,7 +1736,8 @@ void clusterHandleSlaveFailover(void) {
     int needed_quorum = (server.cluster->size / 2) + 1;
     int j;
 
-    /* Set data_age to the number of seconds we are disconnected from the master. */
+    /* Set data_age to the number of seconds we are disconnected from
+     * the master. */
     if (server.repl_state == REDIS_REPL_CONNECTED) {
         data_age = (server.unixtime - server.master->lastinteraction) * 1000;
     } else {
@@ -1765,8 +1767,7 @@ void clusterHandleSlaveFailover(void) {
         return;
 
     /* Compute the time at which we can start an election. */
-    if (server.cluster->failover_auth_time == 0 ||
-        auth_age >
+    if (auth_age >
         server.cluster_node_timeout * REDIS_CLUSTER_FAILOVER_AUTH_RETRY_MULT)
     {
         server.cluster->failover_auth_time = mstime() +
@@ -1775,7 +1776,8 @@ void clusterHandleSlaveFailover(void) {
             random() % 500; /* Random delay between 0 and 500 milliseconds. */
         server.cluster->failover_auth_count = 0;
         server.cluster->failover_auth_sent = 0;
-        redisLog(REDIS_WARNING,"Start of election delayed for %lld milliseconds.",
+        redisLog(REDIS_WARNING,
+            "Start of election delayed for %lld milliseconds.",
             server.cluster->failover_auth_time - mstime());
         return;
     }
@@ -1784,8 +1786,7 @@ void clusterHandleSlaveFailover(void) {
     if (mstime() < server.cluster->failover_auth_time) return;
 
     /* Return ASAP if the election is too old to be valid. */
-    if (mstime() - server.cluster->failover_auth_time > server.cluster_node_timeout)
-        return;
+    if (auth_age > server.cluster_node_timeout) return;
 
     /* Ask for votes if needed. */
     if (server.cluster->failover_auth_sent == 0) {
@@ -1827,7 +1828,8 @@ void clusterHandleSlaveFailover(void) {
         }
 
         /* 3) Update my configEpoch to the epoch of the election. */
-        server.cluster->myself->configEpoch = server.cluster->failover_auth_epoch;
+        server.cluster->myself->configEpoch =
+            server.cluster->failover_auth_epoch;
 
         /* 4) Update state and save config. */
         clusterUpdateState();
diff --git a/src/cluster.h b/src/cluster.h
index 658a364b..28d9af80 100644
--- a/src/cluster.h
+++ b/src/cluster.h
@@ -83,7 +83,7 @@ typedef struct clusterState {
     clusterNode *slots[REDIS_CLUSTER_SLOTS];
     zskiplist *slots_to_keys;
     /* The following fields are used to take the slave state on elections. */
-    mstime_t failover_auth_time;/* Time at which we'll try to get elected in ms*/
+    mstime_t failover_auth_time; /* Time of previous or next election. */
     int failover_auth_count;    /* Number of votes received so far. */
     int failover_auth_sent;     /* True if we already asked for votes. */
     uint64_t failover_auth_epoch; /* Epoch of the current election. */
@@ -91,7 +91,7 @@ typedef struct clusterState {
     uint64_t last_vote_epoch;   /* Epoch of the last vote granted. */
     int todo_before_sleep; /* Things to do in clusterBeforeSleep(). */
     long long stats_bus_messages_sent;  /* Num of msg sent via cluster bus. */
-    long long stats_bus_messages_received; /* Num of msg received via cluster bus. */
+    long long stats_bus_messages_received; /* Num of msg rcvd via cluster bus.*/
 } clusterState;
 
 /* clusterState todo_before_sleep flags. */