refactor: timer pt 3 (#3624)

libtransmission/session.cc

@@ -3000,32 +3000,21 @@ auto makeTorrentDir(std::string_view config_dir)
     return dir;
 }
 
+auto makeEventBase()
+{
+    tr_evthread_init();
+    return std::shared_ptr<event_base>{ event_base_new(), event_base_free };
+}
+
 } // namespace
 
 tr_session::tr_session(std::string_view config_dir)
     : session_id{ tr_time }
+    , event_base_{ makeEventBase() }
+    , timer_maker_{ std::make_unique<libtransmission::EvTimerMaker>(eventBase()) }
     , config_dir_{ config_dir }
     , resume_dir_{ makeResumeDir(config_dir) }
     , torrent_dir_{ makeTorrentDir(config_dir) }
     , session_stats_{ config_dir, time(nullptr) }
 {
 }
-
-void tr_session::setEventBase(event_base* base)
-{
-    TR_ASSERT(event_base_ == nullptr);
-    event_base_ = base;
-    timer_maker_ = std::make_unique<libtransmission::EvTimerMaker>(base);
-}
-
-void tr_session::clearEventBase()
-{
-    timer_maker_.reset();
-    event_base_ = nullptr;
-}
-
-[[nodiscard]] libtransmission::TimerMaker& tr_session::timerMaker() noexcept
-{
-    TR_ASSERT(timer_maker_);
-    return *timer_maker_;
-}

libtransmission/session.h

@@ -128,17 +128,17 @@ struct tr_turtle_info
 struct tr_session
 {
 public:
-    tr_session(std::string_view config_dir);
+    explicit tr_session(std::string_view config_dir);
 
-    [[nodiscard]] constexpr auto* eventBase() noexcept
+    [[nodiscard]] event_base* eventBase() noexcept
     {
-        return event_base_;
+        return event_base_.get();
     }
 
-    void setEventBase(event_base* base);
-    void clearEventBase();
-
-    [[nodiscard]] libtransmission::TimerMaker& timerMaker() noexcept;
+    [[nodiscard]] auto& timerMaker() noexcept
+    {
+        return *timer_maker_;
+    }
 
     [[nodiscard]] constexpr auto& torrents()
     {
@@ -609,8 +609,8 @@ public:
 private:
     static std::recursive_mutex session_mutex_;
 
-    struct event_base* event_base_ = nullptr;
-    std::unique_ptr<libtransmission::TimerMaker> timer_maker_;
+    std::shared_ptr<event_base> const event_base_;
+    std::unique_ptr<libtransmission::TimerMaker> const timer_maker_;
 
     tr_torrents torrents_;
 

libtransmission/trevent.cc

@@ -35,7 +35,7 @@
 
 namespace
 {
-namespace impl
+namespace tr_evthread_init_helpers
 {
 void* lock_alloc(unsigned /*locktype*/)
 {
@@ -109,29 +109,36 @@ unsigned long thread_current_id()
     return std::hash<std::thread::id>()(std::this_thread::get_id());
 }
 
-} // namespace impl
+auto evthread_flag = std::once_flag{};
 
-void tr_evthread_init()
+void initEvthreadsOnce()
 {
-    // evthread_enable_lock_debugging();
+    tr_net_init();
 
-    evthread_lock_callbacks constexpr lock_cbs{ EVTHREAD_LOCK_API_VERSION, EVTHREAD_LOCKTYPE_RECURSIVE,
-                                                impl::lock_alloc,          impl::lock_free,
-                                                impl::lock_lock,           impl::lock_unlock };
+    evthread_lock_callbacks constexpr lock_cbs{
+        EVTHREAD_LOCK_API_VERSION, EVTHREAD_LOCKTYPE_RECURSIVE, lock_alloc, lock_free, lock_lock, lock_unlock
+    };
     evthread_set_lock_callbacks(&lock_cbs);
 
     evthread_condition_callbacks constexpr cond_cbs{ EVTHREAD_CONDITION_API_VERSION,
-                                                     impl::cond_alloc,
-                                                     impl::cond_free,
-                                                     impl::cond_signal,
-                                                     impl::cond_wait };
+                                                     cond_alloc,
+                                                     cond_free,
+                                                     cond_signal,
+                                                     cond_wait };
     evthread_set_condition_callbacks(&cond_cbs);
 
-    evthread_set_id_callback(impl::thread_current_id);
+    evthread_set_id_callback(thread_current_id);
 }
 
+} // namespace tr_evthread_init_helpers
 } // namespace
 
+void tr_evthread_init()
+{
+    using namespace tr_evthread_init_helpers;
+    std::call_once(evthread_flag, initEvthreadsOnce);
+}
+
 /***
 ****
 ***/
@@ -146,7 +153,6 @@ struct tr_event_handle
     std::mutex work_queue_mutex;
     event* work_queue_event = nullptr;
 
-    event_base* base = nullptr;
     tr_session* session = nullptr;
     std::thread::id thread_id;
 };
@@ -181,13 +187,11 @@ static void libeventThreadFunc(tr_event_handle* events)
     tr_evthread_init();
 
     // create the libevent base
-    auto* const base = event_base_new();
+    auto* base = events->session->eventBase();
     auto* const dns_base = evdns_base_new(base, EVDNS_BASE_INITIALIZE_NAMESERVERS);
 
     // initialize the session struct's event fields
-    events->base = base;
     events->work_queue_event = event_new(base, -1, 0, onWorkAvailable, events->session);
-    events->session->setEventBase(base);
     events->session->evdns_base = dns_base;
     events->session->events = events;
 
@@ -204,8 +208,6 @@ static void libeventThreadFunc(tr_event_handle* events)
         evdns_base_free(dns_base, 0);
     }
     event_free(events->work_queue_event);
-    event_base_free(base);
-    events->session->clearEventBase();
     events->session->evdns_base = nullptr;
     events->session->events = nullptr;
     delete events;
@@ -237,7 +239,7 @@ void tr_eventClose(tr_session* session)
         return;
     }
 
-    event_base_loopexit(events->base, nullptr);
+    event_base_loopexit(session->eventBase(), nullptr);
 
     tr_logAddTrace("closing trevent pipe");
 }

libtransmission/trevent.h

@@ -17,6 +17,8 @@
 
 struct tr_session;
 
+void tr_evthread_init();
+
 void tr_eventInit(tr_session* session);
 
 void tr_eventClose(tr_session* session);

tests/libtransmission/watchdir-test.cc

@@ -238,7 +238,7 @@ TEST_P(WatchDirTest, retry)
     auto const test_file = "test.txt"sv;
     createFile(path, test_file);
     processEvents(ThreeRetries);
-    EXPECT_LE(2, std::size(names));
+    EXPECT_LE(2U, std::size(names));
     for (auto const& name : names)
     {
         EXPECT_EQ(test_file, name);