From 839b7dd32e13c7cae260007cd061a47209674994 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Sat, 6 Mar 2021 21:37:16 +0100
Subject: [PATCH] =?UTF-8?q?sixel:=20resize:=20don=E2=80=99t=20resize=20bey?=
 =?UTF-8?q?ond=20the=20current=20max=20geometry?=
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---
 sixel.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/sixel.c b/sixel.c
index eca920de..498d18f2 100644
--- a/sixel.c
+++ b/sixel.c
@@ -855,6 +855,20 @@ resize(struct terminal *term, int new_width, int new_height)
     new_height = (new_height + 6 - 1) / 6 * 6;
     xassert(new_height % 6 == 0);
 
+    if (new_width > term->sixel.max_width)
+        return false;
+
+    /*
+     * Last row may be cropped by the max height, but don’t skip that
+     * last partial row entirely.
+     *
+     * I.e if max height is ‘4’, then allow resizing up to 6, to allow
+     * us to emit that last sixel row. The final image will be cropped
+     * to the current max geometry in unhook.
+     */
+    if (new_height > (term->sixel.max_height + 5) / 6 * 6)
+        return false;
+
     uint32_t *new_data = NULL;
 
     if (new_width == old_width) {