api/joy: refresh only manually on certain events

Refresh joylist when new listener arrives, and when the joy singleton
just gets created. Enumerating joys all the time causes high CPU usage
for some of the users.

Issue: #279
Backtrace-by: @exulant
Reported-by: @aka2k

1 files changed, 7 insertions, 18 deletions

diff --git a/opentrack/win32-joystick.cpp b/opentrack/win32-joystick.cpp
index 728e2f68..5e6f2011 100644
--- a/opentrack/win32-joystick.cpp
+++ b/opentrack/win32-joystick.cpp
@@ -6,7 +6,7 @@
 
 void win32_joy_ctx::poll(fn f)
 {
-    refresh(false);
+    //refresh(false);
     
     QMutexLocker l(&mtx);
     
@@ -94,7 +94,7 @@ win32_joy_ctx::win32_joy_ctx()
         qDebug() << "setup DirectInput8 Creation failed!" << GetLastError();
         assert(!"direct input handle can't be created");
     }
-    refresh(true);
+    refresh();
 }
 
 void win32_joy_ctx::release()
@@ -104,18 +104,12 @@ void win32_joy_ctx::release()
     di = nullptr;
 }
 
-void win32_joy_ctx::refresh(bool first)
+void win32_joy_ctx::refresh()
 {
-    if (!first)
-    {
-        // accessing struct Timer without a lock. worst can happen is seconds
-        // and nanoseconds getting out of sync. no big deal.
-        if (timer_joylist.elapsed_ms() < joylist_refresh_ms)
-            return;
-        timer_joylist.start();
-    }
+    QMutexLocker l(&mtx);
     
-    enum_state st(joys, mtx, fake_main_window, di);
+    qDebug() << "joy list refresh";
+    enum_state st(joys, fake_main_window, di);
 }
 
 QString win32_joy_ctx::guid_to_string(const GUID guid)
@@ -184,16 +178,12 @@ bool win32_joy_ctx::joy::poll(fn f)
 }
 
 win32_joy_ctx::enum_state::enum_state(std::unordered_map<QString, std::shared_ptr<joy>> &joys,
-                                      QMutex& mtx,
                                       QMainWindow &fake_main_window,
                                       LPDIRECTINPUT8 di) :
     fake_main_window(fake_main_window),
     di(di)
 {
-    {
-        QMutexLocker l(&mtx);
-        this->joys = joys;
-    }
+    this->joys = joys;
     
     HRESULT hr;
 
@@ -216,7 +206,6 @@ win32_joy_ctx::enum_state::enum_state(std::unordered_map<QString, std::shared_pt
             it++;
     }
     
-    QMutexLocker l(&mtx);
     joys = this->joys;
 }