01/01: [BEEPMIDI] Don't busy-wait when no notes are playing. CORE-12860

[Thomas Faber]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=eab8a0b968cbb7ef08933…

commit eab8a0b968cbb7ef0893326a5e87704c4da45c7f
Author:     Thomas Faber <thomas.faber(a)reactos.org>
AuthorDate: Tue Feb 27 18:36:22 2018 +0100
Commit:     Thomas Faber <thomas.faber(a)reactos.org>
CommitDate: Thu Mar 1 08:58:33 2018 +0100

    [BEEPMIDI] Don't busy-wait when no notes are playing. CORE-12860
    
    - Use a new work_available event to allow ProcessPlayingNotes to sleep when no
      notes are to be played.
    - Get rid of the pointless thread_termination_complete event, wait on the
      thread handle instead.
    - Don't leak thread_handle.
---
 dll/win32/beepmidi/beepmidi.c | 30 ++++++++++++++++++------------
 1 file changed, 18 insertions(+), 12 deletions(-)

diff --git a/dll/win32/beepmidi/beepmidi.c b/dll/win32/beepmidi/beepmidi.c
index 5fdf62d7bc..b23999845f 100644
--- a/dll/win32/beepmidi/beepmidi.c
+++ b/dll/win32/beepmidi/beepmidi.c
@@ -95,7 +95,7 @@ typedef struct _DeviceInfo
 
     HANDLE thread_handle;
     BOOL terminate_thread;
-    HANDLE thread_termination_complete;
+    HANDLE work_available;
 } DeviceInfo;
 
 DeviceInfo* the_device;
@@ -127,7 +127,7 @@ ProcessPlayingNotes(
     /* We lock the note list only while accessing it */
 
 #ifdef CONTINUOUS_NOTES
-    while ( ! device_info->terminate_thread )
+    while ( WaitForSingleObject(the_device->work_available, INFINITE),
!device_info->terminate_thread )
 #endif
     {
         NoteNode* node;
@@ -198,10 +198,6 @@ ProcessPlayingNotes(
         LeaveCriticalSection(&device_lock);
     }
 
-#ifdef CONTINUOUS_NOTES
-    SetEvent(device_info->thread_termination_complete);
-#endif
-
     return 0;
 }
 
@@ -346,9 +342,9 @@ OpenDevice(
 
     /* This is threading-related code */
 #ifdef CONTINUOUS_NOTES
-    the_device->thread_termination_complete = CreateEvent(NULL, FALSE, FALSE, NULL);
+    the_device->work_available = CreateEvent(NULL, TRUE, FALSE, NULL);
 
-    if ( ! the_device->thread_termination_complete )
+    if ( ! the_device->work_available )
     {
         DPRINT("CreateEvent failed\n");
         HeapFree(heap, 0, the_device);
@@ -365,7 +361,7 @@ OpenDevice(
     if ( ! the_device->thread_handle )
     {
         DPRINT("CreateThread failed\n");
-        CloseHandle(the_device->thread_termination_complete);
+        CloseHandle(the_device->work_available);
         HeapFree(heap, 0, the_device);
         return MMSYSERR_NOMEM;
     }
@@ -391,10 +387,11 @@ CloseDevice(DeviceInfo* device_info)
     /* If we're working in threaded mode we need to wait for thread to die */
 #ifdef CONTINUOUS_NOTES
     the_device->terminate_thread = TRUE;
+    SetEvent(device_info->work_available);
 
-    WaitForSingleObject(the_device->thread_termination_complete, INFINITE);
-
-    CloseHandle(the_device->thread_termination_complete);
+    WaitForSingleObject(the_device->thread_handle, INFINITE);
+    CloseHandle(the_device->thread_handle);
+    CloseHandle(the_device->work_available);
 #endif
 
     /* Let the client application know the device is closing */
@@ -451,6 +448,11 @@ StopNote(
 
             DPRINT("Note stopped - now playing %d notes\n", (int)
device_info->playing_notes_count);
 
+#ifdef CONTINUOUS_NOTES
+            if (device_info->playing_notes_count == 0)
+                ResetEvent(device_info->work_available);
+#endif
+
             LeaveCriticalSection(&device_lock);
             device_info->refresh_notes = TRUE;
 
@@ -561,6 +563,10 @@ PlayNote(
         }
 */
 
+#ifdef CONTINUOUS_NOTES
+        SetEvent(device_info->work_available);
+#endif
+
         LeaveCriticalSection(&device_lock);
 
         DPRINT("Note started - now playing %d notes\n", (int)
device_info->playing_notes_count);