* xterm.c (compose_status): New variable.

(XTread_socket): Pass it by reference to XLookupString.

	* xterm.c: Clean up some of the caps lock handling:
	(x_shift_lock_mask): New variable.
	(x_find_modifier_mappings): Set it, based on the modifier mappings.
	(x_convert_modifiers): Use x_shift_lock_mask, instead of assuming
	that the lock bit always means to shift the character.
	(XTread_socket): When handling KeyPress events, don't pass an
	XComposeStatus structure along to XLookupString.  When handling
	MappingNotify events, call XRefreshKeyboardMapping for both
	MappingModifier and MappingKeyboard events, not just the latter.

src/xterm.c

@@ -1431,18 +1431,23 @@ unsigned int x_mouse_grabbed;
 /* Which modifier keys are on which modifier bits?
 
    With each keystroke, X returns eight bits indicating which modifier
-   keys were held down when the key was pressed.  The low three bits
+   keys were held down when the key was pressed.  The interpretation
-   indicate the state of the shift, shift lock, caps lock, and control
+   of the top five modifier bits depends on what keys are attached
-   keys; their interpretation is fixed.  However, the interpretation
-   of the other five modifier bits depends on what keys are attached
    to them.  If the Meta_L and Meta_R keysyms are on mod5, then mod5
    is the meta bit.
    
    x_meta_mod_mask is a mask containing the bits used for the meta key.
    It may have more than one bit set, if more than one modifier bit
    has meta keys on it.  Basically, if EVENT is a KeyPress event,
-   the meta key is pressed if (EVENT.state & x_meta_mod_mask) != 0.  */
+   the meta key is pressed if (EVENT.state & x_meta_mod_mask) != 0.  
-static int x_meta_mod_mask;
+
+   x_shift_lock_mask is LockMask if the XK_Shift_Lock keysym is on the
+   lock modifier bit, or zero otherwise.  Non-alphabetic keys should
+   only be affected by the lock modifier bit if XK_Shift_Lock is in
+   use; XK_Caps_Lock should only affect alphabetic keys.  With this
+   arrangement, the lock modifier should shift the character if
+   (EVENT.state & x_shift_lock_mask) != 0.  */
+static int x_meta_mod_mask, x_shift_lock_mask;
 
 /* Initialize mode_switch_bit and modifier_meaning.  */
 static void
@@ -1455,6 +1460,7 @@ x_find_modifier_meanings ()
   int alt_mod_mask = 0;
 
   x_meta_mod_mask = 0;
+  x_shift_lock_mask = 0;
   
   XDisplayKeycodes (x_current_display, &min_code, &max_code);
   syms = XGetKeyboardMapping (x_current_display,
@@ -1462,10 +1468,8 @@ x_find_modifier_meanings ()
 			      &syms_per_code);
   mods = XGetModifierMapping (x_current_display);
 
-  /* If CapsLock is on the lock modifier, then only letters should be
+  /* Scan the modifier table to see which modifier bits the Meta and 
-     affected; since XLookupString takes care of this for us, the lock
+     Alt keysyms are on.  */
-     modifier shouldn't set shift_modifier.  However, if ShiftLock is
-     on the lock modifier, then lock should mean shift.  */
   {
     int row, col;	/* The row and column in the modifier table. */
 
@@ -1494,6 +1498,12 @@ x_find_modifier_meanings ()
 		  case XK_Alt_R:
 		    alt_mod_mask |= (1 << row);
 		    break;
+
+		  case XK_Shift_Lock:
+		    /* Ignore this if it's not on the lock modifier.  */
+		    if ((1 << row) == LockMask)
+		      x_shift_lock_mask = LockMask;
+		    break;
 		  }
 	      }
 	  }
@@ -1516,9 +1526,9 @@ static Lisp_Object
 x_convert_modifiers (state)
      unsigned int state;
 {
-  return (  ((state & (ShiftMask | LockMask)) ? shift_modifier : 0)
+  return (  ((state & (ShiftMask | x_shift_lock_mask)) ? shift_modifier : 0)
-	  | ((state & ControlMask)            ? ctrl_modifier  : 0)
+	  | ((state & ControlMask)		       ? ctrl_modifier  : 0)
-	  | ((state & x_meta_mod_mask)        ? meta_modifier  : 0));
+	  | ((state & x_meta_mod_mask)		       ? meta_modifier  : 0));
 }
 
 extern struct frame *x_window_to_scrollbar ();
@@ -1746,6 +1756,15 @@ XTmouse_position (f, x, y, time)
    sometimes don't work.  */
 static Time enter_timestamp;
 
+/* This holds the state XLookupString needs to implement dead keys
+   and other tricks known as "compose processing".  _X Window System_ 
+   says that a portable program can't use this, but Stephen Gildea assures
+   me that letting the compiler initialize it to zeros will work okay.
+
+   This must be defined outside of XTread_socket, for the same reasons
+   given for enter_timestamp, above.  */
+static XComposeStatus compose_status;
+
 /* Communication with window managers. */
 Atom Xatom_wm_protocols;
 
@@ -2030,7 +2049,6 @@ XTread_socket (sd, bufp, numchars, waitp, expected)
 	  if (f != 0)
 	    {
 	      KeySym keysym;
-	      XComposeStatus status;
 	      char copy_buffer[80];
 	      int modifiers = event.xkey.state;
 
@@ -2041,12 +2059,10 @@ XTread_socket (sd, bufp, numchars, waitp, expected)
 		 just clear the meta-key flag to get the 'pure' character.  */
 	      event.xkey.state &= ~Mod1Mask;
 
-	      /* This will have to go some day... */
+	      /* This will have to go some day...  */
-	      nbytes = XLookupString (&event.xkey,
+	      nbytes =
-				      copy_buffer,
+		XLookupString (&event.xkey, copy_buffer, 80, &keysym,
-				      80,
+			       &compose_status);
-				      &keysym,
-				      &status);
 
 	      /* Strip off the vendor-specific keysym bit, and take a shot
 		 at recognizing the codes.  HP servers have extra keysyms
@@ -2400,12 +2416,16 @@ XTread_socket (sd, bufp, numchars, waitp, expected)
 #endif /* ! defined (HAVE_X11) */
 
 	case MappingNotify:
-	  if (event.xmapping.request == MappingKeyboard)
+	  /* Someone has changed the keyboard mapping - update the
-	    /* Someone has changed the keyboard mapping - flush the
+	     local cache.  */
-	       local cache.  */
+	  switch (event.xmapping.request)
-	    XRefreshKeyboardMapping (&event.xmapping);
+	    {
-	  else if (event.xmapping.request == MappingModifier)
+	    case MappingModifier:
-	    x_find_modifier_meanings ();
+	      x_find_modifier_meanings ();
+	      /* This is meant to fall through.  */
+	    case MappingKeyboard:
+	      XRefreshKeyboardMapping (&event.xmapping);
+	    }
 	  break;
 
 	default: