hw/xwin: Return a shutdown flag from winClipboardProc() if we should stop trying

Return a shutdown flag from winClipboardProc(), and use it in
winClipboardThreadProc() to determine if we should stop.

Currently this is set if the clipboard messaging window received a WM_QUIT.

Signed-off-by: Jon TURNEY <jon.turney@dronecode.org.uk>
Reviewed-by: Colin Harrison <colin.harrison@virgin.net>

hw/xwin/winclipboard/thread.c

@@ -56,7 +56,6 @@
  */
 
 extern Bool g_fUnicodeClipboard;
-extern Bool g_fClipboard;
 
 /*
  * Global variables
@@ -85,10 +84,12 @@ static int
  winClipboardIOErrorHandler(Display * pDisplay);
 
 /*
- * Main thread function
+ * Create X11 and Win32 messaging windows, and run message processing loop
+ *
+ * returns TRUE if shutdown was signalled to loop, FALSE if some error occurred
  */
 
-void *
+Bool
 winClipboardProc(char *szDisplay)
 {
     Atom atomClipboard;
@@ -108,6 +109,7 @@ winClipboardProc(char *szDisplay)
     int iRetries;
     Bool fUseUnicode;
     int iSelectError;
+    Bool fShutdown = FALSE;
 
     winDebug("winClipboardProc - Hello\n");
 
@@ -349,8 +351,8 @@ winClipboardProc(char *szDisplay)
     }
 
  winClipboardProc_Exit:
-    /* disable the clipboard, which means the thread will die */
-    g_fClipboard = FALSE;
+    /* broke out of while loop on a shutdown message */
+    fShutdown = TRUE;
 
  winClipboardProc_Done:
     /* Close our Windows window */
@@ -394,7 +396,7 @@ winClipboardProc(char *szDisplay)
     /* global clipboard variable reset */
     g_hwndClipboard = NULL;
 
-    return NULL;
+    return fShutdown;
 }
 
 /*

hw/xwin/winclipboard/winclipboard.h

@@ -96,7 +96,7 @@ void
  * winclipboardthread.c
  */
 
-void *winClipboardProc(char *szDisplay);
+Bool winClipboardProc(char *szDisplay);
 
 void
 winClipboardWindowDestroy(void);

hw/xwin/winclipboardinit.c

@@ -68,6 +68,8 @@ winClipboardThreadProc(void *arg)
 
   while (1)
     {
+      Bool fShutdown;
+
       ++clipboardRestarts;
 
       /* Use our generated cookie for authentication */
@@ -89,11 +91,14 @@ winClipboardThreadProc(void *arg)
       /* Flag that clipboard client has been launched */
       g_fClipboardStarted = TRUE;
 
-      winClipboardProc(szDisplay);
+      fShutdown = winClipboardProc(szDisplay);
 
       /* Flag that clipboard client has stopped */
       g_fClipboardStarted = FALSE;
 
+      if (fShutdown)
+        break;
+
       /* checking if we need to restart */
       if (clipboardRestarts >= WIN_CLIPBOARD_RETRIES) {
         /* terminates clipboard thread but the main server still lives */