Changeset 4168 for trunk/gui/scripts/visviewer.tcl

Timestamp:

Feb 4, 2014 1:17:38 PM (10 years ago)

Author:

ldelgass

Message:

VisViewer::SendBytes? is not re-entrant safe: it will clobber the output buffer.
Since we don't have an output queue, try just blocking on writes to the socket
instead of using tkwait (which can cause us to re-enter SendBytes? if an event
like a Configure/resize comes in while we are waiting).

File:

• trunk/gui/scripts/visviewer.tcl (modified) (1 diff)

trunk/gui/scripts/visviewer.tcl

@@ -453 +453 @@
     set _done($this) 1
     set _buffer(out) $bytes
-    fileevent $_sid writable [itcl::code $this SendHelper]
-    tkwait variable ::Rappture::VisViewer::_done($this)
+    if {1} {
+        # Let's try this approach: allow a write to block so we don't
+        # re-enter SendBytes
+        SendHelper
+    } else {
+        # This can cause us to re-enter SendBytes during the tkwait, which 
+        # is not safe because the _buffer will be clobbered
+        fileevent $_sid writable [itcl::code $this SendHelper]
+        tkwait variable ::Rappture::VisViewer::_done($this)
+    }
     set _buffer(out) ""
     if { [IsConnected] } {