Be more paranoid about ShmCompletion events

Unfortunately HP ships a buggy X server on their thin clients
that send out extra, bogus ShmCompletion events. This screws up our
logic so we need to filter them out. Fortunately they are sent with
an invalid drawable id, so simply verify that.

diff --git a/vncviewer/X11PixelBuffer.cxx b/vncviewer/X11PixelBuffer.cxx
index 046676eb175df9cc6bf55bc14fcabf633060d974..3c41490a76820be3faaaf2a9a5c0daef5e678de5 100644 (file)
--- a/vncviewer/X11PixelBuffer.cxx
+++ b/vncviewer/X11PixelBuffer.cxx
@@ -101,7 +101,7 @@ static PixelFormat display_pf()
 
 X11PixelBuffer::X11PixelBuffer(int width, int height) :
   PlatformPixelBuffer(display_pf(), width, height, NULL, 0),
-  shminfo(NULL), xim(NULL), pendingPutImage(0)
+  shminfo(NULL), xim(NULL), pendingPutImage(0), pendingDrawable(0)
 {
   // Might not be open at this point
   fl_open_display();
@@ -146,6 +146,8 @@ void X11PixelBuffer::draw(int src_x, int src_y, int x, int y, int w, int h)
   if (shminfo) {
     XShmPutImage(fl_display, fl_window, fl_gc, xim, src_x, src_y, x, y, w, h, True);
     pendingPutImage++;
+    assert((pendingPutImage == 1) || (pendingDrawable == fl_window));
+    pendingDrawable = fl_window;
   } else {
     XPutImage(fl_display, fl_window, fl_gc, xim, src_x, src_y, x, y, w, h);
   }
@@ -255,10 +257,18 @@ int X11PixelBuffer::handleSystemEvent(void* event, void* data)
 
   shmevent = (XShmCompletionEvent*)event;
 
+  if (shmevent->send_event)
+    return 0;
+
   for (iter = shmList.begin();iter != shmList.end();++iter) {
     if (shmevent->shmseg != (*iter)->shminfo->shmseg)
       continue;
 
+    /* HP has a buggy X server on their thin clients that sends bogus
+     * extra events with an incorrect drawable id */
+    if (shmevent->drawable != (*iter)->pendingDrawable)
+      continue;
+
     (*iter)->pendingPutImage--;
     assert((*iter)->pendingPutImage >= 0);
 

diff --git a/vncviewer/X11PixelBuffer.h b/vncviewer/X11PixelBuffer.h
index 115984da591ee93053feed5cfccd0bfe25200ee0..a616672d447b18b3b891c89bf26ece9c726c2ac6 100644 (file)
--- a/vncviewer/X11PixelBuffer.h
+++ b/vncviewer/X11PixelBuffer.h
@@ -46,6 +46,7 @@ protected:
   XShmSegmentInfo *shminfo;
   XImage *xim;
   int pendingPutImage;
+  Drawable pendingDrawable;
 
   static std::list<X11PixelBuffer*> shmList;
 };