patch 9.0.1571: RedrawingDisabled not used consistentlyv9.0.1571

Problem:    RedrawingDisabled not used consistently.
Solution:   Avoid RedrawingDisabled going negative.  Set RedrawingDisabled in
            win_split_ins(). (closes #11961)

16 files changed, 86 insertions, 65 deletions

diff --git a/src/autocmd.c b/src/autocmd.c
index 4fa8de7635..c93d4bd754 100644
--- a/src/autocmd.c
+++ b/src/autocmd.c
@@ -1602,10 +1602,7 @@ aucmd_prepbuf(
 	p_acd = FALSE;
 #endif
 
-	// no redrawing and don't set the window title
-	++RedrawingDisabled;
 	(void)win_split_ins(0, WSP_TOP, auc_win, 0);
-	--RedrawingDisabled;
 	(void)win_comp_pos();   // recompute window positions
 	p_ea = save_ea;
 #ifdef FEAT_AUTOCHDIR
@@ -2334,7 +2331,8 @@ apply_autocmds_group(
 	    active_apc_list = patcmd.next;
     }
 
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
     autocmd_busy = save_autocmd_busy;
     filechangeshell_busy = FALSE;
     autocmd_nested = save_autocmd_nested;
diff --git a/src/buffer.c b/src/buffer.c
index dc279ffb19..ff7c50fae1 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -2506,11 +2506,10 @@ buflist_getfile(
     }
 
     ++RedrawingDisabled;
+    int retval = FAIL;
     if (GETFILE_SUCCESS(getfile(buf->b_fnum, NULL, NULL,
 				     (options & GETF_SETMARK), lnum, forceit)))
     {
-	--RedrawingDisabled;
-
 	// cursor is at to BOL and w_cursor.lnum is checked due to getfile()
 	if (!p_sol && col != 0)
 	{
@@ -2519,10 +2518,12 @@ buflist_getfile(
 	    curwin->w_cursor.coladd = 0;
 	    curwin->w_set_curswant = TRUE;
 	}
-	return OK;
+	retval = OK;
     }
-    --RedrawingDisabled;
-    return FAIL;
+
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
+    return retval;
 }
 
 /*
diff --git a/src/cmdexpand.c b/src/cmdexpand.c
index 4ef9c31121..46615383c0 100644
--- a/src/cmdexpand.c
+++ b/src/cmdexpand.c
@@ -3937,14 +3937,12 @@ wildmenu_process_key(cmdline_info_T *cclp, int key, expand_T *xp)
 wildmenu_cleanup(cmdline_info_T *cclp UNUSED)
 {
     int skt = KeyTyped;
-#ifdef FEAT_EVAL
-    int old_RedrawingDisabled = RedrawingDisabled;
-#endif
 
     if (!p_wmnu || wild_menu_showing == 0)
 	return;
 
 #ifdef FEAT_EVAL
+    int save_RedrawingDisabled = RedrawingDisabled;
     if (cclp->input_fn)
 	RedrawingDisabled = 0;
 #endif
@@ -3974,7 +3972,7 @@ wildmenu_cleanup(cmdline_info_T *cclp UNUSED)
     wild_menu_showing = 0;
 #ifdef FEAT_EVAL
     if (cclp->input_fn)
-	RedrawingDisabled = old_RedrawingDisabled;
+	RedrawingDisabled = save_RedrawingDisabled;
 #endif
 }
 
diff --git a/src/debugger.c b/src/debugger.c
index a04a078361..393e11e414 100644
--- a/src/debugger.c
+++ b/src/debugger.c
@@ -287,7 +287,8 @@ do_debug(char_u *cmd)
     }
     vim_free(cmdline);
 
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
     --no_wait_return;
     redraw_all_later(UPD_NOT_VALID);
     need_wait_return = FALSE;
diff --git a/src/edit.c b/src/edit.c
index 64edddce8d..a882d67feb 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -3613,7 +3613,8 @@ ins_esc(
     temp = curwin->w_cursor.col;
     if (disabled_redraw)
     {
-	--RedrawingDisabled;
+	if (RedrawingDisabled > 0)
+	    --RedrawingDisabled;
 	disabled_redraw = FALSE;
     }
     if (!arrow_used)
diff --git a/src/ex_cmds.c b/src/ex_cmds.c
index 0fd6d10f71..20d4d9a2ea 100644
--- a/src/ex_cmds.c
+++ b/src/ex_cmds.c
@@ -3219,7 +3219,8 @@ do_ecmd(
 	(void)keymap_init();
 #endif
 
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
     did_inc_redrawing_disabled = FALSE;
     if (!skip_redraw)
     {
@@ -3263,7 +3264,7 @@ do_ecmd(
 #endif
 
 theend:
-    if (did_inc_redrawing_disabled)
+    if (did_inc_redrawing_disabled && RedrawingDisabled > 0)
 	--RedrawingDisabled;
 #if defined(FEAT_EVAL)
     if (did_set_swapcommand)
@@ -3735,7 +3736,6 @@ ex_substitute(exarg_T *eap)
     int		sublen;
     int		got_quit = FALSE;
     int		got_match = FALSE;
-    int		temp;
     int		which_pat;
     char_u	*cmd;
     int		save_State;
@@ -4316,7 +4316,7 @@ ex_substitute(exarg_T *eap)
 #endif
 			    // Invert the matched string.
 			    // Remove the inversion afterwards.
-			    temp = RedrawingDisabled;
+			    int save_RedrawingDisabled = RedrawingDisabled;
 			    RedrawingDisabled = 0;
 
 			    // avoid calling update_screen() in vgetorpeek()
@@ -4386,7 +4386,7 @@ ex_substitute(exarg_T *eap)
 			    msg_scroll = i;
 			    showruler(TRUE);
 			    windgoto(msg_row, msg_col);
-			    RedrawingDisabled = temp;
+			    RedrawingDisabled = save_RedrawingDisabled;
 
 #ifdef USE_ON_FLY_SCROLL
 			    dont_scroll = FALSE; // allow scrolling here
diff --git a/src/ex_docmd.c b/src/ex_docmd.c
index 430ca2ccb4..69af1ca1d0 100644
--- a/src/ex_docmd.c
+++ b/src/ex_docmd.c
@@ -550,7 +550,8 @@ do_exmode(
 #ifdef FEAT_GUI
     --hold_gui_events;
 #endif
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
     --no_wait_return;
     update_screen(UPD_CLEAR);
     need_wait_return = FALSE;
@@ -631,7 +632,7 @@ do_cmdline(
     static int	recursive = 0;		// recursive depth
     int		msg_didout_before_start = 0;
     int		count = 0;		// line number count
-    int		did_inc = FALSE;	// incremented RedrawingDisabled
+    int		did_inc_RedrawingDisabled = FALSE;
     int		retval = OK;
 #ifdef FEAT_EVAL
     cstack_T	cstack;			// conditional stack
@@ -977,7 +978,7 @@ do_cmdline(
 		msg_scroll = TRUE;  // put messages below each other
 		++no_wait_return;   // don't wait for return until finished
 		++RedrawingDisabled;
-		did_inc = TRUE;
+		did_inc_RedrawingDisabled = TRUE;
 	    }
 	}
 
@@ -1336,9 +1337,10 @@ do_cmdline(
      * hit return before redrawing the screen. With the ":global" command we do
      * this only once after the command is finished.
      */
-    if (did_inc)
+    if (did_inc_RedrawingDisabled)
     {
-	--RedrawingDisabled;
+	if (RedrawingDisabled > 0)
+	    --RedrawingDisabled;
 	--no_wait_return;
 	msg_scroll = FALSE;
 
@@ -7170,7 +7172,7 @@ do_exedit(
 
 		if (exmode_was != EXMODE_VIM)
 		    settmode(TMODE_RAW);
-		int save_rd = RedrawingDisabled;
+		int save_RedrawingDisabled = RedrawingDisabled;
 		RedrawingDisabled = 0;
 		int save_nwr = no_wait_return;
 		no_wait_return = 0;
@@ -7187,7 +7189,7 @@ do_exedit(
 		main_loop(FALSE, TRUE);
 
 		pending_exmode_active = FALSE;
-		RedrawingDisabled = save_rd;
+		RedrawingDisabled = save_RedrawingDisabled;
 		no_wait_return = save_nwr;
 		msg_scroll = save_ms;
 #ifdef FEAT_GUI
@@ -8438,11 +8440,12 @@ ex_redraw(exarg_T *eap)
     void
 redraw_cmd(int clear)
 {
-    int		r = RedrawingDisabled;
-    int		p = p_lz;
-
+    int save_RedrawingDisabled = RedrawingDisabled;
     RedrawingDisabled = 0;
+
+    int save_p_lz = p_lz;
     p_lz = FALSE;
+
     validate_cursor();
     update_topline();
     update_screen(clear ? UPD_CLEAR : VIsual_active ? UPD_INVERTED : 0);
@@ -8454,8 +8457,8 @@ redraw_cmd(int clear)
 # endif
 	resize_console_buf();
 #endif
-    RedrawingDisabled = r;
-    p_lz = p;
+    RedrawingDisabled = save_RedrawingDisabled;
+    p_lz = save_p_lz;
 
     // After drawing the statusline screen_attr may still be set.
     screen_stop_highlight();
@@ -8480,9 +8483,6 @@ redraw_cmd(int clear)
     static void
 ex_redrawstatus(exarg_T *eap UNUSED)
 {
-    int		r = RedrawingDisabled;
-    int		p = p_lz;
-
     if (eap->forceit)
 	status_redraw_all();
     else
@@ -8490,14 +8490,18 @@ ex_redrawstatus(exarg_T *eap UNUSED)
     if (msg_scrolled && (State & MODE_CMDLINE))
 	return;  // redraw later
 
+    int save_RedrawingDisabled = RedrawingDisabled;
     RedrawingDisabled = 0;
+
+    int save_p_lz = p_lz;
     p_lz = FALSE;
+
     if (State & MODE_CMDLINE)
 	redraw_statuslines();
     else
 	update_screen(VIsual_active ? UPD_INVERTED : 0);
-    RedrawingDisabled = r;
-    p_lz = p;
+    RedrawingDisabled = save_RedrawingDisabled;
+    p_lz = save_p_lz;
     out_flush();
 }
 
@@ -8507,16 +8511,16 @@ ex_redrawstatus(exarg_T *eap UNUSED)
     static void
 ex_redrawtabline(exarg_T *eap UNUSED)
 {
-    int		r = RedrawingDisabled;
-    int		p = p_lz;
-
+    int save_RedrawingDisabled = RedrawingDisabled;
     RedrawingDisabled = 0;
+
+    int save_p_lz = p_lz;
     p_lz = FALSE;
 
     draw_tabline();
 
-    RedrawingDisabled = r;
-    p_lz = p;
+    RedrawingDisabled = save_RedrawingDisabled;
+    p_lz = save_p_lz;
     out_flush();
 }
 
diff --git a/src/ex_getln.c b/src/ex_getln.c
index 595286aa34..fbda2cc00d 100644
--- a/src/ex_getln.c
+++ b/src/ex_getln.c
@@ -4545,7 +4545,7 @@ open_cmdwin(void)
     if (restart_edit != 0)	// autocmd with ":startinsert"
 	stuffcharReadbuff(K_NOP);
 
-    i = RedrawingDisabled;
+    int save_RedrawingDisabled = RedrawingDisabled;
     RedrawingDisabled = 0;
 
     /*
@@ -4553,7 +4553,7 @@ open_cmdwin(void)
      */
     main_loop(TRUE, FALSE);
 
-    RedrawingDisabled = i;
+    RedrawingDisabled = save_RedrawingDisabled;
 
 # ifdef FEAT_FOLDING
     save_KeyTyped = KeyTyped;
diff --git a/src/insexpand.c b/src/insexpand.c
index c20cb4f258..3cfdface44 100644
--- a/src/insexpand.c
+++ b/src/insexpand.c
@@ -2969,12 +2969,13 @@ f_complete_add(typval_T *argvars, typval_T *rettv)
     void
 f_complete_check(typval_T *argvars UNUSED, typval_T *rettv)
 {
-    int		saved = RedrawingDisabled;
-
+    int save_RedrawingDisabled = RedrawingDisabled;
     RedrawingDisabled = 0;
+
     ins_compl_check_keys(0, TRUE);
     rettv->vval.v_number = ins_compl_interrupted();
-    RedrawingDisabled = saved;
+
+    RedrawingDisabled = save_RedrawingDisabled;
 }
 
 /*
@@ -5079,8 +5080,7 @@ ins_complete(int c, int enable_pum)
 show_pum(int prev_w_wrow, int prev_w_leftcol)
 {
     // RedrawingDisabled may be set when invoked through complete().
-    int n = RedrawingDisabled;
-
+    int save_RedrawingDisabled = RedrawingDisabled;
     RedrawingDisabled = 0;
 
     // If the cursor moved or the display scrolled we need to remove the pum
@@ -5091,7 +5091,8 @@ show_pum(int prev_w_wrow, int prev_w_leftcol)
 
     ins_compl_show_pum();
     setcursor();
-    RedrawingDisabled = n;
+
+    RedrawingDisabled = save_RedrawingDisabled;
 }
 
 /*
diff --git a/src/os_unix.c b/src/os_unix.c
index 5bcac85609..194e4d3134 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -4594,7 +4594,7 @@ mch_call_shell_terminal(
 
     // Only require pressing Enter when redrawing, to avoid that system() gets
     // the hit-enter prompt even though it didn't output anything.
-    if (!RedrawingDisabled)
+    if (RedrawingDisabled == 0)
 	wait_return(TRUE);
     do_buffer(DOBUF_WIPE, DOBUF_FIRST, FORWARD, buf->b_fnum, TRUE);
 
diff --git a/src/popupmenu.c b/src/popupmenu.c
index 7210420e1a..651f510693 100644
--- a/src/popupmenu.c
+++ b/src/popupmenu.c
@@ -865,7 +865,8 @@ pum_set_selected(int n, int repeat UNUSED)
 	    ++no_u_sync;
 	    resized = prepare_tagpreview(FALSE, FALSE, use_popup);
 	    --no_u_sync;
-	    --RedrawingDisabled;
+	    if (RedrawingDisabled > 0)
+		--RedrawingDisabled;
 	    g_do_tagpreview = 0;
 
 	    if (curwin->w_p_pvw
diff --git a/src/screen.c b/src/screen.c
index 08e147d108..e9bc79267b 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -2696,7 +2696,8 @@ give_up:
 #endif
 
     entered = FALSE;
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
 
     /*
      * Do not apply autocommands more than 3 times to avoid an endless loop
@@ -4496,7 +4497,7 @@ redrawing(void)
 	return 0;
     else
 #endif
-	return ((!RedrawingDisabled
+	return ((RedrawingDisabled == 0
 #ifdef FEAT_EVAL
 		    || ignore_redraw_flag_for_testing
 #endif
diff --git a/src/tag.c b/src/tag.c
index 1ee67b44dd..8003156f0f 100644
--- a/src/tag.c
+++ b/src/tag.c
@@ -3829,7 +3829,8 @@ jumpto_tag(
 	if (win_split(postponed_split > 0 ? postponed_split : 0,
 						postponed_split_flags) == FAIL)
 	{
-	    --RedrawingDisabled;
+	    if (RedrawingDisabled > 0)
+		--RedrawingDisabled;
 	    goto erret;
 	}
 	RESET_BINDING(curwin);
@@ -4032,11 +4033,13 @@ jumpto_tag(
 	}
 #endif
 
-	--RedrawingDisabled;
+	if (RedrawingDisabled > 0)
+	    --RedrawingDisabled;
     }
     else
     {
-	--RedrawingDisabled;
+	if (RedrawingDisabled > 0)
+	    --RedrawingDisabled;
 	got_int = FALSE;  // don't want entering window to fail
 
 	if (postponed_split)		// close the window
diff --git a/src/userfunc.c b/src/userfunc.c
index 6f0d59dfd3..5b2c876e3b 100644
--- a/src/userfunc.c
+++ b/src/userfunc.c
@@ -3048,7 +3048,8 @@ call_user_func(
     // Invoke functions added with ":defer".
     handle_defer_one(current_funccal);
 
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
 
     // when the function was aborted because of an error, return -1
     if ((did_emsg && (fp->uf_flags & FC_ABORT)) || rettv->v_type == VAR_UNKNOWN)
diff --git a/src/version.c b/src/version.c
index 07fec75dcd..8d0d519e4d 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@ static char *(features[]) =
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1571,
+/**/
     1570,
 /**/
     1569,
diff --git a/src/window.c b/src/window.c
index 18f07b17a4..926a3f348f 100644
--- a/src/window.c
+++ b/src/window.c
@@ -950,6 +950,10 @@ win_split_ins(
     int		minheight;
     int		wmh1;
     int		did_set_fraction = FALSE;
+    int		retval = FAIL;
+
+    // Do not redraw here, curwin->w_buffer may be invalid.
+    ++RedrawingDisabled;
 
     if (flags & WSP_TOP)
 	oldwin = firstwin;
@@ -964,7 +968,7 @@ win_split_ins(
 	if (VISIBLE_HEIGHT(oldwin) <= p_wmh && new_wp == NULL)
 	{
 	    emsg(_(e_not_enough_room));
-	    return FAIL;
+	    goto theend;
 	}
 	need_status = STATUS_HEIGHT;
     }
@@ -1022,7 +1026,7 @@ win_split_ins(
 	if (available < needed && new_wp == NULL)
 	{
 	    emsg(_(e_not_enough_room));
-	    return FAIL;
+	    goto theend;
 	}
 	if (new_size == 0)
 	    new_size = oldwin->w_width / 2;
@@ -1105,7 +1109,7 @@ win_split_ins(
 	if (available < needed && new_wp == NULL)
 	{
 	    emsg(_(e_not_enough_room));
-	    return FAIL;
+	    goto theend;
 	}
 	oldwin_height = oldwin->w_height;
 	if (need_status)
@@ -1188,13 +1192,13 @@ win_split_ins(
     if (new_wp == NULL)
     {
 	if (wp == NULL)
-	    return FAIL;
+	    goto theend;
 
 	new_frame(wp);
 	if (wp->w_frame == NULL)
 	{
 	    win_free(wp, NULL);
-	    return FAIL;
+	    goto theend;
 	}
 
 	// make the contents of the new window the same as the current one
@@ -1435,8 +1439,12 @@ win_split_ins(
 	p_wiw = i;
     else
 	p_wh = i;
+    retval = OK;
 
-    return OK;
+theend:
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
+    return retval;
 }
 
 
@@ -2460,7 +2468,8 @@ close_windows(
 		}
     }
 
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
 
     if (count != tabpage_index(NULL))
 	apply_autocmds(EVENT_TABCLOSED, NULL, NULL, FALSE, curbuf);