Re: [RP] xgrabkeyboard race/fail patch

[twb]

Quoth Cameron Patrick <address@hidden> on or about Sun, 23 Nov 2003 11:07:16 
+0800:
> On Sun, Nov 23, 2003 at 02:01:20PM +1100, twb wrote:
> 
> | This patch lets RP handle failure to XGrabKeyboard.
> 
> Eww.  Could you extract your error-loopy bit out into a separate
> function and call that?  Having several copies of essentially identical
> code strewn around the place is yucky.
> 
> Cameron.

I know.  It should be a cpp macro, but I haven't worked them out yet.
Also, I've only tried the one in input.c, because I don't use -i've
:fselect or :resize -- it was more an afterthought.  Finally, I have
an irrational fear of cosmetic branching, because deep down where
normal people keep religion, it feels like I'm wasting processage on a
useless BRA.

Anyhow, how's this?  I put the definition in global.h, which is
probably wrong.  Should be in rp.h?  Did the diff properly this time.
-trent

-- 
<darkaeon> How much money do you make now? I know it can't be much since you're 
on irc.
<MadHatter>I'm not even on irc.  
<darkaeon> I programmed some lego mindstorms to get on irc for me.

cvs server: Diffing .
Index: actions.c
===================================================================
RCS file: /cvsroot/ratpoison/ratpoison/src/actions.c,v
retrieving revision 1.185
diff -u -r1.185 actions.c
--- actions.c   18 Nov 2003 05:06:35 -0000      1.185
+++ actions.c   23 Nov 2003 07:44:35 -0000
@@ -1691,7 +1691,11 @@
         scale. */
       if (num_frames (s) < 2) return NULL;
 
-      XGrabKeyboard (dpy, s->key_window, False, GrabModeSync, GrabModeAsync, 
CurrentTime);
+      rp_xgrabkeyboard (dpy, s->key_window, False, GrabModeSync, 
GrabModeAsync, CurrentTime) 
+       {
+         message (MESSAGE_XGRABKEYBOARD_ERROR);
+         return NULL;
+       }
 
       /* Save the frameset in case the user aborts. */
       bk = screen_copy_frameset (s);
@@ -1841,7 +1845,15 @@
                           NULL};
 
   XMapRaised (dpy, s->help_window);
-  XGrabKeyboard (dpy, s->help_window, False, GrabModeSync, GrabModeAsync, 
CurrentTime);
+  rp_xgrabkeyboard (dpy, s->help_window, False, GrabModeSync, GrabModeAsync, 
CurrentTime)
+    {
+      XUnmapWindow (dpy, s->help_window);
+      /* The help window overlaps the bar, so redraw it. */
+      if (current_screen()->bar_is_raised)
+       show_last_message();
+      message (MESSAGE_XGRABKEYBOARD_ERROR);
+      return NULL;
+    }
 
   /* Find the longest line. */
   for(i=0; license_text[i]; i++)
@@ -1915,7 +1927,15 @@
       char *keysym_name;
 
       XMapRaised (dpy, s->help_window);
-      XGrabKeyboard (dpy, s->help_window, False, GrabModeSync, GrabModeAsync, 
CurrentTime);
+      rp_xgrabkeyboard (dpy, s->help_window, False, GrabModeSync, 
GrabModeAsync, CurrentTime)
+       {
+         XUnmapWindow (dpy, s->help_window);
+         /* The help window overlaps the bar, so redraw it. */
+         if (current_screen()->bar_is_raised)
+           show_last_message();
+         message (MESSAGE_XGRABKEYBOARD_ERROR);
+         return NULL;
+       }
 
       XDrawString (dpy, s->help_window, s->normal_gc,
                    10, y + defaults.font->max_bounds.ascent,
@@ -3332,7 +3352,11 @@
       XSync (dpy, False);
 
       /* Read a key. */
-      XGrabKeyboard (dpy, s->key_window, False, GrabModeSync, GrabModeAsync, 
CurrentTime);
+      rp_xgrabkeyboard (dpy, s->key_window, False, GrabModeSync, 
GrabModeAsync, CurrentTime)
+       {
+         message (MESSAGE_XGRABKEYBOARD_ERROR);
+         return NULL;
+       }
       read_key (&c, &mod, NULL, 0);
       XUngrabKeyboard (dpy, CurrentTime);
 
@@ -3979,7 +4003,12 @@
       return NULL;
     }
 
-  XGrabKeyboard (dpy, current_screen()->key_window, False, GrabModeSync, 
GrabModeAsync, CurrentTime);
+  
+  rp_xgrabkeyboard (dpy, current_screen()->key_window, False, GrabModeSync, 
GrabModeAsync, CurrentTime)
+    {
+      message (MESSAGE_XGRABKEYBOARD_ERROR);
+      return NULL;
+    }
 
   /* Change the mouse icon to indicate to the user we are waiting for
      more keystrokes */
Index: globals.h
===================================================================
RCS file: /cvsroot/ratpoison/ratpoison/src/globals.h,v
retrieving revision 1.8
diff -u -r1.8 globals.h
--- globals.h   15 Oct 2003 22:26:19 -0000      1.8
+++ globals.h   23 Nov 2003 07:44:36 -0000
@@ -141,4 +141,18 @@
 void set_rp_window_focus (rp_window *win);
 void set_window_focus (Window window);
 
+#define XGRABKEYBOARD_LOOP_DEPTH 10
+#define XGRABKEYBOARD_UDELAY 10000 
+#define rp_xgrabkeyboard(display, grab_window, owner_events, pointer_mode, 
keyboard_mode, time) \
+        int XGrabKeyboardError=0; \
+        int XGrabKeyboardLoop=0; \
+        while (XGrabKeyboardError = XGrabKeyboard (display, grab_window, 
owner_events, pointer_mode, keyboard_mode, time) \
+              && XGrabKeyboardLoop < XGRABKEYBOARD_LOOP_DEPTH) { \
+         PRINT_DEBUG(("Couldn't grab the keyboard!  Retry in 0.01 
seconds.\n")); \
+         ++XGrabKeyboardLoop; \
+         usleep(XGRABKEYBOARD_UDELAY); \
+        } \
+        if (XGrabKeyboardError) 
+
+
 #endif
Index: input.c
===================================================================
RCS file: /cvsroot/ratpoison/ratpoison/src/input.c,v
retrieving revision 1.38
diff -u -r1.38 input.c
--- input.c     2 Nov 2003 06:10:14 -0000       1.38
+++ input.c     23 Nov 2003 07:44:36 -0000
@@ -400,7 +400,13 @@
 
   update_input_window (s, line);
 
-  XGrabKeyboard (dpy, s->input_window, False, GrabModeSync, GrabModeAsync, 
CurrentTime);
+  rp_xgrabkeyboard (dpy, s->input_window, False, GrabModeSync, GrabModeAsync, 
CurrentTime)
+    {
+      input_line_free (line);
+      XUnmapWindow (dpy, s->input_window);
+      message (MESSAGE_XGRABKEYBOARD_ERROR);
+      return NULL;
+    }
 
   for (;;)
     {
Index: messages.h
===================================================================
RCS file: /cvsroot/ratpoison/ratpoison/src/messages.h,v
retrieving revision 1.13
diff -u -r1.13 messages.h
--- messages.h  25 May 2003 10:56:20 -0000      1.13
+++ messages.h  23 Nov 2003 07:44:36 -0000
@@ -46,4 +46,6 @@
 #define MESSAGE_WELCOME        " Welcome to ratpoison! Hit `%s %s' for help. "
 #define MESSAGE_FRAME_STRING   " Current Frame "
 
+#define MESSAGE_XGRABKEYBOARD_ERROR " Could not grab keyboard (asynchronously) 
"
+
 #endif /* ! _RATPOISON_MESSAGES_H */