From 72e8f24832a2582b6dd15f37f8e3b97358cc0a04 Mon Sep 17 00:00:00 2001
From: Willem Thiart <himself@willemthiart.com>
Date: Wed, 18 Nov 2015 20:06:46 +0700
Subject: [PATCH] Only candidates read requestvote responses

---
 src/raft_server.c   |  3 ++-
 tests/test_server.c | 24 +++++++++++++++++++++++-
 2 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/src/raft_server.c b/src/raft_server.c
index 343e97db..3f40b1db 100644
--- a/src/raft_server.c
+++ b/src/raft_server.c
@@ -116,6 +116,7 @@ void raft_become_candidate(raft_server_t* me_)
     raft_set_state(me_, RAFT_STATE_CANDIDATE);
 
     /* we need a random factor here to prevent simultaneous candidates */
+    /* TODO: this should probably be lower */
     me->timeout_elapsed = rand() % me->election_timeout;
 
     for (i = 0; i < me->num_nodes; i++)
@@ -454,7 +455,7 @@ int raft_recv_requestvote_response(raft_server_t* me_,
     __log(me_, "node responded to requestvote: %d status: %s",
           node, r->vote_granted == 1 ? "granted" : "not granted");
 
-    if (raft_is_leader(me_))
+    if (!raft_is_candidate(me_))
         return 0;
 
     assert(node < me->num_nodes);
diff --git a/tests/test_server.c b/tests/test_server.c
index 9c50263d..6519c26a 100644
--- a/tests/test_server.c
+++ b/tests/test_server.c
@@ -444,6 +444,8 @@ void TestRaft_server_recv_requestvote_response_increase_votes_for_me(
     raft_set_current_term(r, 1);
     CuAssertTrue(tc, 0 == raft_get_nvotes_for_me(r));
 
+    raft_become_candidate(r);
+
     msg_requestvote_response_t rvr;
     memset(&rvr, 0, sizeof(msg_requestvote_response_t));
     rvr.term = 1;
@@ -452,6 +454,26 @@ void TestRaft_server_recv_requestvote_response_increase_votes_for_me(
     CuAssertTrue(tc, 1 == raft_get_nvotes_for_me(r));
 }
 
+void TestRaft_server_recv_requestvote_response_must_be_candidate_to_receive(
+    CuTest * tc
+    )
+{
+    void *r = raft_new();
+    raft_add_node(r, (void*)1, 1);
+    raft_add_node(r, (void*)2, 0);
+    raft_set_current_term(r, 1);
+    CuAssertTrue(tc, 0 == raft_get_nvotes_for_me(r));
+
+    raft_become_leader(r);
+
+    msg_requestvote_response_t rvr;
+    memset(&rvr, 0, sizeof(msg_requestvote_response_t));
+    rvr.term = 1;
+    rvr.vote_granted = 1;
+    raft_recv_requestvote_response(r, 1, &rvr);
+    CuAssertTrue(tc, 0 == raft_get_nvotes_for_me(r));
+}
+
 /* Reply false if term < currentTerm (§5.1) */
 void TestRaft_server_recv_requestvote_reply_false_if_term_less_than_current_term(
     CuTest * tc
@@ -1168,7 +1190,7 @@ void TestRaft_follower_becoming_candidate_resets_election_timeout(CuTest * tc)
 
     raft_become_candidate(r);
     /* time is selected randomly */
-    CuAssertTrue(tc, raft_get_timeout_elapsed(r) < 900);
+    CuAssertTrue(tc, raft_get_timeout_elapsed(r) < 1000);
 }
 
 void TestRaft_follower_recv_appendentries_resets_election_timeout(