Changeset 18756 in vbox for trunk/src/VBox/GuestHost

Timestamp:

Apr 6, 2009 1:53:45 PM (16 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

45732

Message:

HostServices/SharedClipboard: a couple of fixes and some assertions

File:

• trunk/src/VBox/GuestHost/SharedClipboard/x11-clipboard.cpp (modified) (5 diffs)

trunk/src/VBox/GuestHost/SharedClipboard/x11-clipboard.cpp

@@ -762 +762 @@
         return;
 
+    /* We set this to NULL when the event thread exits.  It really should
+     * have exited at this point, when we are about to unload the code from
+     * memory. */
+    Assert(pCtx->widget == NULL);
     RTSemEventDestroy(pCtx->waitForData);
 }
@@ -823 +827 @@
  * Shut down the shared clipboard X11 backend.
  * @note  X11 backend code
+ * @note  Any requests from this object to get clipboard data from VBox
+ *        *must* have completed or aborted before we are called, as
+ *        otherwise the X11 event loop will still be waiting for the request
+ *        to return and will not be able to terminate.
  */
 int VBoxX11ClipboardStopX11(VBOXCLIPBOARDCONTEXTX11 *pCtx)
@@ -835 +843 @@
         return VINF_SUCCESS;
 
+    /* This might mean that we are getting stopped twice. */
+    AssertReturn(pCtx->widget != NULL, VERR_WRONG_ORDER);
     pCtx->eOwner = NONE;
     pCtx->X11TextFormat = INVALID;
@@ -840 +850 @@
     LogRelFunc(("stopping the shared clipboard X11 backend\n"));
 
-    /* Set the termination flag.  This has been observed to block if it was set
-     * during a request for clipboard data coming from X11, so only we do it
-     * after releasing any such requests. */
+    /* Set the termination flag to tell the Xt event loop to exit.  We
+     * reiterate that any outstanding requests from the X11 event loop to
+     * the VBox part *must* have returned before we do this. */
     XtAppSetExitFlag(pCtx->appContext);
     /* Wake up the event loop */
@@ -861 +871 @@
         LogRelFunc(("rc=%Rrc\n", rc));
     XtCloseDisplay(XtDisplay(pCtx->widget));
+    pCtx->widget = NULL;  /* For sanity assertions. */
     LogFlowFunc(("returning %Rrc.\n", rc));
     return rc;