chore: Use unique_ptr for WorkerThread#worker (apache#703)

Co-authored-by: Twice <[email protected]>

Author: jackwener

src/server.cc

@@ -54,19 +54,18 @@ Server::Server(Engine::Storage *storage, Config *config) :
   cluster_ = std::unique_ptr<Cluster>(new Cluster(this, config_->binds, config_->port));
 
   for (int i = 0; i < config->workers; i++) {
-    auto worker = new Worker(this, config);
+    auto worker = Util::MakeUnique<Worker>(this, config);
     // multiple workers can't listen to the same unix socket, so
     // listen unix socket only from a single worker - the first one
     if (!config->unixsocket.empty() && i == 0) {
       Status s = worker->ListenUnixSocket(config->unixsocket, config->unixsocketperm, config->backlog);
       if (!s.IsOK()) {
         LOG(ERROR) << "[server] Failed to listen on unix socket: "<< config->unixsocket
                    << ", encounter error: " << s.Msg();
-        delete worker;
         exit(1);
       }
     }
-    worker_threads_.emplace_back(new WorkerThread(worker));
+    worker_threads_.emplace_back(Util::MakeUnique<WorkerThread>(std::move(worker)));
   }
   AdjustOpenFilesLimit();
   slow_log_.SetMaxEntries(config->slowlog_max_len);
@@ -79,9 +78,6 @@ Server::Server(Engine::Storage *storage, Config *config) :
 }
 
 Server::~Server() {
-  for (const auto &worker_thread : worker_threads_) {
-    delete worker_thread;
-  }
   for (const auto &iter : conn_ctxs_) {
     delete iter.first;
   }
@@ -121,7 +117,7 @@ Status Server::Start() {
     }
   }
 
-  for (const auto worker : worker_threads_) {
+  for (const auto& worker : worker_threads_) {
     worker->Start();
   }
   task_runner_.Start();
@@ -175,7 +171,7 @@ Status Server::Start() {
 void Server::Stop() {
   stop_ = true;
   if (replication_thread_) replication_thread_->Stop();
-  for (const auto worker : worker_threads_) {
+  for (const auto& worker : worker_threads_) {
     worker->Stop();
   }
   DisconnectSlaves();
@@ -184,7 +180,7 @@ void Server::Stop() {
 }
 
 void Server::Join() {
-  for (const auto worker : worker_threads_) {
+  for (const auto& worker : worker_threads_) {
     worker->Join();
   }
   task_runner_.Join();

src/server.h

@@ -261,7 +261,7 @@ class Server {
   std::thread cron_thread_;
   std::thread compaction_checker_thread_;
   TaskRunner task_runner_;
-  std::vector<WorkerThread *> worker_threads_;
+  std::vector<std::unique_ptr<WorkerThread>> worker_threads_;
   std::unique_ptr<ReplicationThread> replication_thread_;
 };
 

src/worker.h

@@ -26,6 +26,7 @@
 #include <memory>
 #include <thread>
 #include <string>
+#include <utility>
 #include <vector>
 #include <event2/buffer.h>
 #include <event2/bufferevent.h>
@@ -89,16 +90,16 @@ class Worker {
 
 class WorkerThread {
  public:
-  explicit WorkerThread(Worker *worker) : worker_(worker) {}
-  ~WorkerThread() { delete worker_; }
+  explicit WorkerThread(std::unique_ptr<Worker> worker) : worker_(std::move(worker)) {}
+  ~WorkerThread() = default;
   WorkerThread(const WorkerThread&) = delete;
   WorkerThread(WorkerThread&&) = delete;
-  Worker *GetWorker() { return worker_; }
+  Worker *GetWorker() { return worker_.get(); }
   void Start();
   void Stop();
   void Join();
 
  private:
   std::thread t_;
-  Worker *worker_;
+  std::unique_ptr<Worker> worker_;
 };