diff --git a/src/braft/node.cpp b/src/braft/node.cpp
index afe57084..67dd6d19 100644
--- a/src/braft/node.cpp
+++ b/src/braft/node.cpp
@@ -2237,12 +2237,11 @@ void NodeImpl::after_shutdown() {
     }
 }
 
-void NodeImpl::handle_install_snapshot_request(brpc::Controller* controller,
+void NodeImpl::handle_install_snapshot_request(brpc::Controller* cntl,
                                     const InstallSnapshotRequest* request,
                                     InstallSnapshotResponse* response,
                                     google::protobuf::Closure* done) {
     brpc::ClosureGuard done_guard(done);
-    brpc::Controller* cntl = (brpc::Controller*)controller;
 
     if (_snapshot_executor == NULL) {
         cntl->SetFailed(EINVAL, "Not support snapshot");
@@ -2271,7 +2270,7 @@ void NodeImpl::handle_install_snapshot_request(brpc::Controller* controller,
     // check stale term
     if (request->term() < _current_term) {
         LOG(WARNING) << "node " << _group_id << ":" << _server_id
-                     << " ignore stale AppendEntries from " << request->server_id()
+                     << " ignore stale InstallSnapshot from " << request->server_id()
                      << " in term " << request->term()
                      << " current_term " << _current_term;
         response->set_term(_current_term);
@@ -2324,11 +2323,11 @@ butil::Status NodeImpl::read_committed_user_log(const int64_t index, UserLog* us
     }
     int64_t cur_index = index;
     LogEntry* entry = _log_manager->get_entry(cur_index);
-    if (entry == NULL){
+    if (entry == NULL) {
         return butil::Status(ELOGDELETED, "user log is deleted at index:%" PRId64, index);
     }
     do {
-        if (entry->type == ENTRY_TYPE_DATA){
+        if (entry->type == ENTRY_TYPE_DATA) {
             user_log->set_log_index(cur_index);
             user_log->set_log_data(entry->data);
             entry->Release();
diff --git a/src/braft/replicator.cpp b/src/braft/replicator.cpp
index a0272d73..f63a3083 100644
--- a/src/braft/replicator.cpp
+++ b/src/braft/replicator.cpp
@@ -326,9 +326,10 @@ void Replicator::_on_heartbeat_returned(
         node_impl->Release();
         return;
     }
+
     bool readonly = response->has_readonly() && response->readonly();
     BRAFT_VLOG << ss.str() << " readonly " << readonly;
-    if (rpc_send_time > r->_last_rpc_send_timestamp){
+    if (rpc_send_time > r->_last_rpc_send_timestamp) {
         r->_last_rpc_send_timestamp = rpc_send_time; 
     }
     r->_start_heartbeat_timer(start_time_us);
@@ -775,10 +776,10 @@ void Replicator::_install_snapshot() {
     _st.st = INSTALLING_SNAPSHOT;
 
     _reader = _options.snapshot_storage->open();
-    if (!_reader){
+    if (!_reader) {
         if (_options.snapshot_throttle) {
             _options.snapshot_throttle->finish_one_task(true);
-	}
+        }
         NodeImpl *node_impl = _options.node;
         node_impl->AddRef();
         CHECK_EQ(0, bthread_id_unlock(_id)) << "Fail to unlock " << _id;
@@ -802,7 +803,7 @@ void Replicator::_install_snapshot() {
     }
     SnapshotMeta meta;
     // report error on failure
-    if (_reader->load_meta(&meta) != 0){
+    if (_reader->load_meta(&meta) != 0) {
         std::string snapshot_path = _reader->get_path();
         NodeImpl *node_impl = _options.node;
         node_impl->AddRef();
diff --git a/src/braft/snapshot_executor.cpp b/src/braft/snapshot_executor.cpp
index 1aba640e..1971affd 100644
--- a/src/braft/snapshot_executor.cpp
+++ b/src/braft/snapshot_executor.cpp
@@ -395,7 +395,7 @@ void SnapshotExecutor::install_snapshot(brpc::Controller* cntl,
     SnapshotMeta meta = request->meta();
 
     // check if install_snapshot tasks num exceeds threshold 
-    if (_snapshot_throttle && !_snapshot_throttle->add_one_more_task(false)){
+    if (_snapshot_throttle && !_snapshot_throttle->add_one_more_task(false)) {
         LOG(WARNING) << "Fail to install snapshot";
         cntl->SetFailed(EBUSY, "Fail to add install_snapshot tasks now");
         return;
@@ -429,7 +429,7 @@ void SnapshotExecutor::install_snapshot(brpc::Controller* cntl,
     done_guard.release();
     CHECK(_cur_copier);
     _cur_copier->join();
-    // when coping finished or canceled, more install_snapshot tasks are allowed
+    // when copying finished or canceled, more install_snapshot tasks are allowed
     if (_snapshot_throttle) {
         _snapshot_throttle->finish_one_task(false);
     }
@@ -553,12 +553,12 @@ int SnapshotExecutor::register_downloading_snapshot(DownloadingSnapshot* ds) {
         rc = 1;
     } else if (m->request->meta().last_included_index() 
             > ds->request->meta().last_included_index()) {
-        // |is| is older
+        // |ds| is older
         LOG(WARNING) << "Register failed: is installing a newer one.";
         ds->cntl->SetFailed(EINVAL, "A newer snapshot is under installing");
         return -1;
     } else {
-        // |is| is newer
+        // |ds| is newer
         if (_loading_snapshot) {
             // We can't interrupt the loading one
             LOG(WARNING) << "Register failed: is loading an older snapshot.";
diff --git a/test/memory_file_system_adaptor.h b/test/memory_file_system_adaptor.h
index 8706d8d7..deec27cd 100644
--- a/test/memory_file_system_adaptor.h
+++ b/test/memory_file_system_adaptor.h
@@ -276,7 +276,7 @@ class MemoryFileSystemAdaptor : public braft::FileSystemAdaptor {
                 continue;
             } else if (sub_path.BaseName().value() == "..") {
                 ++ignore;
-            } else if (ignore > 0){
+            } else if (ignore > 0) {
                 --ignore;
             } else {
                 subpaths.push_back(sub_path.BaseName());
@@ -358,7 +358,7 @@ class MemoryFileSystemAdaptor : public braft::FileSystemAdaptor {
                 continue;
             } else if (sub_path.BaseName().value() == "..") {
                 ++ignore;
-            } else if (ignore > 0){
+            } else if (ignore > 0) {
                 --ignore;
             } else {
                 subpaths.push_back(sub_path.BaseName());