From cca310dacfa95c43da82eb74136c56ad285fc33b Mon Sep 17 00:00:00 2001
From: Jim Blandy <jimb@redhat.com>
Date: Thu, 17 Jun 1993 21:23:29 +0000
Subject: [PATCH] * keyboard.c (read_key_sequence): Don't confuse mock input
 with 	function-key-map expansion, and continue reading mock events when 
 the current sequence is unbound.

	* keyboard.c (read_key_sequence): After providing a prefix symbol
	for a mouse event, modify the mouse event to indicate that that
	won't need to be done again, by putting the event's position
	symbol in a list.

	* keyboard.c (read_key_sequence): When returning mock input which
	has run off the end of the current maps, make sure the events get
	echoed, and make it into this-command-keys.

	* keyboard.c (read_key_sequence): When re-reading a previously
	read mouse click which requires a prefix symbol, make sure to set
	last_real_key_start appropriately, so we can properly drop
	button-down events.
---
 src/keyboard.c | 52 +++++++++++++++++++++++++++++++-------------------
 1 file changed, 32 insertions(+), 20 deletions(-)

diff --git a/src/keyboard.c b/src/keyboard.c
index dd5e213a235..49d27b0dcdc 100644
--- a/src/keyboard.c
+++ b/src/keyboard.c
@@ -3687,11 +3687,14 @@ read_key_sequence (keybuf, bufsize, prompt)
   if (INTERACTIVE)
     echo_truncate (echo_start);
 
-  /* If the best binding for the current key sequence is a keymap,
-     or we may be looking at a function key's escape sequence, keep
-     on reading.  */
+  /* If the best binding for the current key sequence is a keymap, or
+     we may be looking at a function key's escape sequence, keep on
+     reading.  */
   while ((first_binding < nmaps && ! NILP (submaps[first_binding]))
-	 || (first_binding >= nmaps && fkey_start < t))
+	 || (first_binding >= nmaps
+	     && fkey_start < t
+	     /* mock input is never part of a function key's sequence.  */
+	     && mock_input <= fkey_start))
     {
       Lisp_Object key;
       int used_mouse_menu = 0;
@@ -3763,7 +3766,11 @@ read_key_sequence (keybuf, bufsize, prompt)
 	     Furthermore, key sequences beginning with mouse clicks
 	     are read using the keymaps of the buffer clicked on, not
 	     the current buffer.  So we may have to switch the buffer
-	     here.  */
+	     here.
+
+	     If the event was obtained from the unread_command_events
+	     queue, then don't expand it; we did that the first time
+	     we read it.  */
 	  if (EVENT_HAS_PARAMETERS (key))
 	    {
 	      Lisp_Object kind = EVENT_HEAD_KIND (EVENT_HEAD (key));
@@ -3782,19 +3789,8 @@ read_key_sequence (keybuf, bufsize, prompt)
 		      && XTYPE (XWINDOW (window)->buffer) == Lisp_Buffer
 		      && XBUFFER (XWINDOW (window)->buffer) != current_buffer)
 		    {
-		      if (XTYPE (posn) == Lisp_Symbol)
-			{
-			  if (t + 1 >= bufsize)
-			    error ("key sequence too long");
-			  keybuf[t] = posn;
-			  keybuf[t+1] = key;
-			  mock_input = t + 2;
-			}
-		      else
-			{
-			  keybuf[t] = key;
-			  mock_input = t + 1;
-			}
+		      keybuf[t] = key;
+		      mock_input = t + 1;
 
 		      /* Arrange to go back to the original buffer once we're
 			 done reading the key sequence.  Note that we can't
@@ -3819,12 +3815,25 @@ read_key_sequence (keybuf, bufsize, prompt)
 		      keybuf[t+1] = key;
 		      mock_input = t + 2;
 
+		      /* Zap the position in key, so we know that we've
+			 expanded it, and don't try to do so again.  */
+		      POSN_BUFFER_POSN (EVENT_START (key))
+			= Fcons (posn, Qnil);
+
 		      /* If we switched buffers while reading the first event,
 			 replay in case we switched keymaps too.  */
 		      if (buf != current_buffer && t == 0)
 			goto replay_sequence;
 		      goto replay_key;
 		    }
+		  else if (XTYPE (posn) == Lisp_Cons)
+		    {
+		      /* We're looking at the second event of a
+			 sequence which we expanded before.  Set
+			 last_real_key_start appropriately.  */
+		      if (last_real_key_start == t && t > 0)
+			last_real_key_start = t - 1;
+		    }
 		}
 	      else if (EQ (kind, Qswitch_frame))
 		{
@@ -4057,8 +4066,11 @@ read_key_sequence (keybuf, bufsize, prompt)
      read-key-sequence will always return a logical unit.
 
      Better ideas?  */
-  if (mock_input > t)
-    t = mock_input;
+  for (; t < mock_input; t++)
+    {
+      echo_char (keybuf[t]);
+      add_command_key (keybuf[t]);
+    }
 
   return t;
 }