From e2cf40ef99bdb6e15b8229244a0f29a6859191b0 Mon Sep 17 00:00:00 2001
From: Michael Grant <mgrant@grant.org>
Date: Mon, 23 Feb 2026 08:08:31 +0000
Subject: [PATCH] Fix crash cause by not having a wp pointer in tty.c.

---
 screen-write.c | 34 ++++++++++++++++++++++++++++++++++
 tmux.h         |  3 +++
 tty.c          | 42 +++++-------------------------------------
 3 files changed, 42 insertions(+), 37 deletions(-)

diff --git a/screen-write.c b/screen-write.c
index df176083..ecbd9e11 100644
--- a/screen-write.c
+++ b/screen-write.c
@@ -1814,6 +1814,39 @@ screen_write_collect_scroll(struct screen_write_ctx *ctx, u_int bg)
 	TAILQ_INSERT_TAIL(&ctx->s->write_list[s->rlower].items, ci, entry);
 }
 
+/* Return 1 if there is a floating window pane overlapping this pane. */
+static int
+screen_write_pane_obscured(struct window_pane *base_wp)
+{
+	struct window_pane	*wp;
+	struct window		*w;
+	int			 found_self = 0;
+
+	if (base_wp == NULL)
+		return(0);
+	w = base_wp->window;
+
+	/* Check if there is a floating pane. xxxx borders? scrollbars? */
+	TAILQ_FOREACH_REVERSE(wp, &w->z_index, window_panes_zindex, zentry) {
+		if (wp == base_wp) {
+			found_self = 1;
+			continue;
+		}
+		if (found_self && wp->flags & PANE_FLOATING &&
+		    ! (wp->flags & PANE_MINIMISED) &&
+		    ((wp->yoff >= base_wp->yoff &&
+		    wp->yoff <= base_wp->yoff + (int)base_wp->sy) ||
+		    (wp->yoff + (int)wp->sy >= base_wp->yoff &&
+		    wp->yoff + wp->sy <= base_wp->yoff + base_wp->sy)) &&
+		    ((wp->xoff >= base_wp->xoff &&
+		    wp->xoff <= base_wp->xoff + (int)base_wp->sx) ||
+		    (wp->xoff + (int)wp->sx >= base_wp->xoff &&
+		    wp->xoff + wp->sx <= base_wp->xoff + base_wp->sx)))
+			return (1);
+		}
+	return (0);
+}
+
 /* Flush collected lines. */
 static void
 screen_write_collect_flush(struct screen_write_ctx *ctx, int scroll_only,
@@ -1853,6 +1886,7 @@ screen_write_collect_flush(struct screen_write_ctx *ctx, int scroll_only,
 			 ttyctx.orlower -= (wp->yoff + wp->sy - wp->window->sy);
 		ttyctx.num = ctx->scrolled;
 		ttyctx.bg = ctx->bg;
+		ttyctx.obscured = screen_write_pane_obscured(wp);
 		tty_write(tty_cmd_scrollup, &ttyctx);
 
 		if (wp != NULL)
diff --git a/tmux.h b/tmux.h
index 2c7a4376..36510028 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1721,6 +1721,9 @@ struct tty_ctx {
 	u_int			 woy;
 	u_int			 wsx;
 	u_int			 wsy;
+
+	/* tty partly obscured, it will need to be surgically scrolled. */
+	u_int			 obscured;
 };
 
 /* Saved message entry. */
diff --git a/tty.c b/tty.c
index f969f46d..75cdbe2d 100644
--- a/tty.c
+++ b/tty.c
@@ -1527,7 +1527,7 @@ tty_set_client_cb(struct tty_ctx *ttyctx, struct client *c)
 	ttyctx->bigger = tty_window_offset(&c->tty, &ttyctx->wox, &ttyctx->woy,
 	    &ttyctx->wsx, &ttyctx->wsy);
 
-	ttyctx->yoff = ttyctx->ryoff = wp->yoff;
+	ttyctx->yoff = ttyctx->ryoff = wp->yoff;  /* xxxx find another way to do this */
 	if (status_at_line(c) == 0)
 		ttyctx->yoff += status_line_size(c);
 
@@ -1555,7 +1555,7 @@ tty_draw_images(struct client *c, struct window_pane *wp, struct screen *s)
 		ttyctx.sy = wp->sy;
 
 		ttyctx.ptr = im;
-		ttyctx.arg = wp;
+		ttyctx.arg = wp;  /* xxx remove this */
 		ttyctx.set_client_cb = tty_set_client_cb;
 		ttyctx.allow_invisible_panes = 1;
 		tty_write_one(tty_cmd_sixelimage, c, &ttyctx);
@@ -1866,39 +1866,6 @@ tty_cmd_linefeed(struct tty *tty, const struct tty_ctx *ctx)
 	tty_putc(tty, '\n');
 }
 
-/* Return 1 if there is a floating window pane overlapping this pane. */
-static int
-tty_is_obscured(const struct tty_ctx *ctx)
-{
-	struct window_pane	*base_wp = ctx->arg, *wp;
-	struct window		*w;
-	int			 found_self = 0;
-
-	if (base_wp == NULL)
-		return(0);
-	w = base_wp->window;
-
-	/* Check if there is a floating pane. xxxx borders? scrollbars? */
-	TAILQ_FOREACH_REVERSE(wp, &w->z_index, window_panes_zindex, zentry) {
-		if (wp == base_wp) {
-			found_self = 1;
-			continue;
-		}
-		if (found_self && wp->flags & PANE_FLOATING &&
-		    ! (wp->flags & PANE_MINIMISED) &&
-		    ((wp->yoff >= base_wp->yoff &&
-		    wp->yoff <= base_wp->yoff + (int)base_wp->sy) ||
-		    (wp->yoff + (int)wp->sy >= base_wp->yoff &&
-		    wp->yoff + wp->sy <= base_wp->yoff + base_wp->sy)) &&
-		    ((wp->xoff >= base_wp->xoff &&
-		    wp->xoff <= base_wp->xoff + (int)base_wp->sx) ||
-		    (wp->xoff + (int)wp->sx >= base_wp->xoff &&
-		    wp->xoff + wp->sx <= base_wp->xoff + base_wp->sx)))
-			return (1);
-		}
-	return (0);
-}
-
 void
 tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
 {
@@ -1911,7 +1878,8 @@ tty_cmd_scrollup(struct tty *tty, const struct tty_ctx *ctx)
 	    !tty_term_has(tty->term, TTYC_CSR) ||
 	    ctx->sx == 1 ||
 	    ctx->sy == 1 ||
-	    c->overlay_check != NULL) {
+	    c->overlay_check != NULL ||
+	    ctx->obscured) {
 		tty_redraw_region(tty, ctx);
 		return;
 	}
@@ -2069,7 +2037,7 @@ tty_cmd_cell(struct tty *tty, const struct tty_ctx *ctx)
 {
 	const struct grid_cell	*gcp = ctx->cell;
 	struct screen		*s = ctx->s;
-	struct visible_ranges	*r;
+	struct visible_ranges	*r = NULL;
 	u_int			 px, py, i, vis = 0;
 
 	px = ctx->xoff + ctx->ocx - ctx->wox;