libX11: Extend Event functions to handle IOErrors

To allow for suspend/resume NX has changed _XReadEvents() and _XIOError(). _XIOError() does not simply exit but returns. And _XReadEvents() returns after _XIOError(). But as the original _XReadEvents() is supposed to block until at least one event is there calling functions are not prepared for situations where no event is available. These calling functions have to check that condition., Some of the calling functions already had that check but the UnlockDisplay() call was missing. Fixes https://github.com/ArcticaProject/nx-libs/issues/118

libX11: Extend Event functions to handle IOErrors
b7d7ff3e · Ulrich Sibiller · Mike Gabriel · e079b0b3 · b7d7ff3e · b7d7ff3e
Commit b7d7ff3e authored Jun 24, 2016 by Ulrich Sibiller Committed by Mike Gabriel Jun 25, 2016
6 changed files
--- a/nx-X11/lib/X11/IfEvent.c
+++ b/nx-X11/lib/X11/IfEvent.c
@@ -73,6 +73,7 @@ XIfEvent (dpy, event, predicate, arg)
 		prev = NULL;
 #ifdef NX_TRANS_SOCKET
            if (_XGetIOError(dpy)) {
+                UnlockDisplay(dpy);
                return 0;
            }
 #endif

--- a/nx-X11/lib/X11/MaskEvent.c
+++ b/nx-X11/lib/X11/MaskEvent.c
@@ -77,6 +77,7 @@ XMaskEvent (dpy, mask, event)
 		prev = NULL;
 #ifdef NX_TRANS_SOCKET
            if (_XGetIOError(dpy)) {
+                UnlockDisplay(dpy);
                return 0;
            }
 #endif

--- a/nx-X11/lib/X11/NextEvent.c
+++ b/nx-X11/lib/X11/NextEvent.c
@@ -48,6 +48,12 @@ XNextEvent (dpy, event)
 	
 	if (dpy->head == NULL)
 	    _XReadEvents(dpy);
+#ifdef NX_TRANS_SOCKET
+	if (_XGetIOError(dpy)) {
+	    UnlockDisplay(dpy);
+	    return 0;
+	}
+#endif
 	qelt = dpy->head;
 	*event = qelt->event;
 	_XDeq(dpy, NULL, qelt);

--- a/nx-X11/lib/X11/PeekEvent.c
+++ b/nx-X11/lib/X11/PeekEvent.c
@@ -46,6 +46,12 @@ XPeekEvent (dpy, event)
 	LockDisplay(dpy);
 	if (dpy->head == NULL)
 	    _XReadEvents(dpy);
+#ifdef NX_TRANS_SOCKET
+	if (_XGetIOError(dpy)) {
+	    UnlockDisplay(dpy);
+	    return 1;
+	}
+#endif
 	*event = (dpy->head)->event;
 	UnlockDisplay(dpy);
 	return 1;

--- a/nx-X11/lib/X11/PeekIfEv.c
+++ b/nx-X11/lib/X11/PeekIfEv.c
@@ -73,6 +73,7 @@ XPeekIfEvent (dpy, event, predicate, arg)
 		prev = NULL;
 #ifdef NX_TRANS_SOCKET
            if (_XGetIOError(dpy)) {
+                UnlockDisplay(dpy);
                return 0;
            }
 #endif

--- a/nx-X11/lib/X11/WinEvent.c
+++ b/nx-X11/lib/X11/WinEvent.c
@@ -79,5 +79,11 @@ XWindowEvent (dpy, w, mask, event)
 	    if (prev && prev->qserial_num != qe_serial)
 		/* another thread has snatched this event */
 		prev = NULL;
+#ifdef NX_TRANS_SOCKET
+	    if (_XGetIOError(dpy)) {
+	      UnlockDisplay(dpy);
+	      return 0;
+	    }
+#endif
 	}
 }