patch 9.1.0116: win_split_ins may not check available room
Problem: win_split_ins has no check for E36 when moving an existing
window
Solution: check for room and fix the issues in f_win_splitmove()
(Sean Dewar)
win_split_ins has no check for E36 when moving an existing window,
allowing for layouts with many overlapping zero-sized windows to be
created (which may also cause drawing issues with tablines and such).
f_win_splitmove also has some bugs.
So check for room and fix the issues in f_win_splitmove. Handle failure
in the two relevant win_split_ins callers by restoring the original
layout, and factor the common logic into win_splitmove.
Don't check for room when opening an autocommand window, as it's a
temporary window that's rarely interacted with or drawn anyhow, and is
rather important for some autocommands.
Issues fixed in f_win_splitmove:
- Error if splitting is disallowed.
- Fix heap-use-after-frees if autocommands fired from switching to "targetwin"
close "wp" or "oldwin".
- Fix splitting the wrong window if autocommands fired from switching to
"targetwin" switch to a different window.
- Ensure -1 is returned for all errors.
Also handle allocation failure a bit earlier in make_snapshot (callers,
except win_splitmove, don't really care if a snapshot can't be made, so
just ignore the return value).
Note: Test_smoothscroll_in_zero_width_window failed after these changes with
E36, as it was using the previous behaviour to create a zero-width window.
I've fixed the test such that it fails with UBSAN as expected when v9.0.1367 is
reverted (and simplified it too).
related: #14042
Signed-off-by: Sean Dewar <6256228+seandewar@users.noreply.github.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/evalwindow.c b/src/evalwindow.c
index 7d035d5..5016eb4 100644
--- a/src/evalwindow.c
+++ b/src/evalwindow.c
@@ -953,59 +953,17 @@
}
/*
- * Move the window wp into a new split of targetwin in a given direction
- */
- static void
-win_move_into_split(win_T *wp, win_T *targetwin, int size, int flags)
-{
- int dir;
- int height = wp->w_height;
- win_T *oldwin = curwin;
-
- if (wp == targetwin)
- return;
-
- // Jump to the target window
- if (curwin != targetwin)
- win_goto(targetwin);
-
- // Remove the old window and frame from the tree of frames
- (void)winframe_remove(wp, &dir, NULL);
- win_remove(wp, NULL);
- last_status(FALSE); // may need to remove last status line
- (void)win_comp_pos(); // recompute window positions
-
- // Split a window on the desired side and put the old window there
- (void)win_split_ins(size, flags, wp, dir);
-
- // If splitting horizontally, try to preserve height
- if (size == 0 && !(flags & WSP_VERT))
- {
- win_setheight_win(height, wp);
- if (p_ea)
- win_equal(wp, TRUE, 'v');
- }
-
-#if defined(FEAT_GUI)
- // When 'guioptions' includes 'L' or 'R' may have to remove or add
- // scrollbars. Have to update them anyway.
- gui_may_update_scrollbars();
-#endif
-
- if (oldwin != curwin)
- win_goto(oldwin);
-}
-
-/*
* "win_splitmove()" function
*/
void
f_win_splitmove(typval_T *argvars, typval_T *rettv)
{
- win_T *wp;
- win_T *targetwin;
+ win_T *wp, *targetwin;
+ win_T *oldwin = curwin;
int flags = 0, size = 0;
+ rettv->vval.v_number = -1;
+
if (in_vim9script()
&& (check_for_number_arg(argvars, 0) == FAIL
|| check_for_number_arg(argvars, 1) == FAIL
@@ -1020,7 +978,6 @@
|| win_valid_popup(wp) || win_valid_popup(targetwin))
{
emsg(_(e_invalid_window_number));
- rettv->vval.v_number = -1;
return;
}
@@ -1040,7 +997,24 @@
size = (int)dict_get_number(d, "size");
}
- win_move_into_split(wp, targetwin, size, flags);
+ // Check if we can split the target before we bother switching windows.
+ if (check_split_disallowed(targetwin) == FAIL)
+ return;
+
+ if (curwin != targetwin)
+ win_goto(targetwin);
+
+ // Autocommands may have sent us elsewhere or closed "wp" or "oldwin".
+ if (curwin == targetwin && win_valid(wp))
+ {
+ if (win_splitmove(wp, size, flags) == OK)
+ rettv->vval.v_number = 0;
+ }
+ else
+ emsg(_(e_autocommands_caused_command_to_abort));
+
+ if (oldwin != curwin && win_valid(oldwin))
+ win_goto(oldwin);
}
/*