patch 9.1.0365: Crash when typing many keys with D- modifier

Problem:  Crash when typing many keys with D- modifier (after 9.1.0227).
Solution: Don't treat a 0x80 byte inside a special sequence as the start
          of a special sequence (zeertzjq).

closes: #14613

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>

src/getchar.c

@@ -1286,12 +1286,11 @@ del_typebuf(int len, int offset)
  */
 typedef struct
 {
-    int		prev_c;
     char_u	buf[MB_MAXBYTES * 3 + 4];
+    int		prev_c;
     size_t	buflen;
-    unsigned	pending;
+    unsigned	pending_special;
-    int		in_special;
+    unsigned	pending_mbyte;
-    int		in_mbyte;
 } gotchars_state_T;
 
 /*
@@ -1303,32 +1302,29 @@ gotchars_add_byte(gotchars_state_T *state, char_u byte)
 {
     int		c = state->buf[state->buflen++] = byte;
     int		retval = FALSE;
+    int		in_special = state->pending_special > 0;
+    int		in_mbyte = state->pending_mbyte > 0;
 
-    if (state->pending > 0)
+    if (in_special)
-	state->pending--;
+	state->pending_special--;
-
+    else if (c == K_SPECIAL
-    // When receiving a special key sequence, store it until we have all
-    // the bytes and we can decide what to do with it.
-    if ((state->pending == 0 || state->in_mbyte)
-	    && (c == K_SPECIAL
 #ifdef FEAT_GUI
 		|| c == CSI
 #endif
-	       ))
+	    )
-    {
+	// When receiving a special key sequence, store it until we have all
-	state->pending += 2;
+	// the bytes and we can decide what to do with it.
-	if (!state->in_mbyte)
+	state->pending_special = 2;
-	    state->in_special = TRUE;
-    }
 
-    if (state->pending > 0)
+    if (state->pending_special > 0)
 	goto ret_false;
 
-    if (!state->in_mbyte)
+    if (in_mbyte)
+	state->pending_mbyte--;
+    else
     {
-	if (state->in_special)
+	if (in_special)
 	{
-	    state->in_special = FALSE;
 	    if (state->prev_c == KS_MODIFIER)
 		// When receiving a modifier, wait for the modified key.
 		goto ret_false;
@@ -1341,16 +1337,11 @@ gotchars_add_byte(gotchars_state_T *state, char_u byte)
 	// When receiving a multibyte character, store it until we have all
 	// the bytes, so that it won't be split between two buffer blocks,
 	// and delete_buff_tail() will work properly.
-	state->pending = MB_BYTE2LEN_CHECK(c) - 1;
+	state->pending_mbyte = MB_BYTE2LEN_CHECK(c) - 1;
-	if (state->pending > 0)
-	{
-	    state->in_mbyte = TRUE;
-	    goto ret_false;
-	}
     }
-    else
+
-	// Stored all bytes of a multibyte character.
+    if (state->pending_mbyte > 0)
-	state->in_mbyte = FALSE;
+	goto ret_false;
 
     retval = TRUE;
 ret_false:

src/testdir/test_mapping.vim

@@ -248,21 +248,25 @@ func Test_map_meta_multibyte()
 endfunc
 
 func Test_map_super_quotes()
-  if has('gui_gtk') || has('gui_gtk3') || has("macos")
+  if "\<D-j>"[-1:] == '>'
-    imap <D-"> foo
+    throw 'Skipped: <D- modifier not supported'
-    call feedkeys("Go-\<*D-\">-\<Esc>", "xt")
-    call assert_equal("-foo-", getline('$'))
-    set nomodified
-    iunmap <D-">
   endif
+
+  imap <D-"> foo
+  call feedkeys("Go-\<*D-\">-\<Esc>", "xt")
+  call assert_equal("-foo-", getline('$'))
+  set nomodified
+  iunmap <D-">
 endfunc
 
 func Test_map_super_multibyte()
-  if has('gui_gtk') || has('gui_gtk3') || has("macos")
+  if "\<D-j>"[-1:] == '>'
-    imap <D-á> foo
+    throw 'Skipped: <D- modifier not supported'
-    call assert_match('i  <D-á>\s*foo', execute('imap'))
-    iunmap <D-á>
   endif
+
+  imap <D-á> foo
+  call assert_match('i  <D-á>\s*foo', execute('imap'))
+  iunmap <D-á>
 endfunc
 
 func Test_abbr_after_line_join()

src/testdir/test_registers.vim

@@ -261,6 +261,19 @@ func Test_zz_recording_with_select_mode_utf8_gui()
   call Run_test_recording_with_select_mode_utf8()
 endfunc
 
+func Test_recording_with_super_mod()
+  if "\<D-j>"[-1:] == '>'
+    throw 'Skipped: <D- modifier not supported'
+  endif
+
+  nnoremap <D-j> <Ignore>
+  let s = repeat("\<D-j>", 1000)
+  " This used to crash Vim
+  call feedkeys($'qr{s}q', 'tx')
+  call assert_equal(s, @r)
+  nunmap <D-j>
+endfunc
+
 " Test for executing the last used register (@)
 func Test_last_used_exec_reg()
   " Test for the @: command

src/version.c

@@ -704,6 +704,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    365,
 /**/
     364,
 /**/