From: tokyo4j <hrak1529@gmail.com>
Date: Sun, 13 Oct 2024 22:55:15 +0000 (+0900)
Subject: src/theme.c: fix misuse of wl_list_for_each
X-Git-Url: https://git.mdlowis.com/?a=commitdiff_plain;h=5f3600b0b89c6200e2763c149a46baaa2bafbc4f;p=proto%2Flabwc.git

src/theme.c: fix misuse of wl_list_for_each

The iterator value of `wl_list_for_each` should never be referenced
outside the loop because it points to invalid memory location when the
list is empty.
---

diff --git a/src/theme.c b/src/theme.c
index ae2ae400..c0af2ad6 100644
--- a/src/theme.c
+++ b/src/theme.c
@@ -297,29 +297,30 @@ load_button(struct theme *theme, struct button *b, int active)
 			buttons[b->type][non_hover_state_set]);
 	}
 
-	struct title_button *leftmost_button = NULL;
+	/*
+	 * If the loaded button is at the corner of the titlebar, also create
+	 * rounded variants.
+	 */
+	uint8_t rounded_state_set = b->state_set | LAB_BS_ROUNDED;
+
+	struct title_button *leftmost_button;
 	wl_list_for_each(leftmost_button,
 			&rc.title_buttons_left, link) {
+		if (leftmost_button->type == b->type) {
+			create_rounded_buffer(theme, LAB_CORNER_TOP_LEFT,
+				&buttons[b->type][rounded_state_set], *buffer);
+		}
 		break;
 	}
-	struct title_button *rightmost_button = NULL;
+	struct title_button *rightmost_button;
 	wl_list_for_each_reverse(rightmost_button,
 			&rc.title_buttons_right, link) {
+		if (rightmost_button->type == b->type) {
+			create_rounded_buffer(theme, LAB_CORNER_TOP_RIGHT,
+				&buttons[b->type][rounded_state_set], *buffer);
+		}
 		break;
 	}
-
-	/*
-	 * If the loaded button is at the corner of the titlebar, also create
-	 * rounded variants.
-	 */
-	uint8_t rounded_state_set = b->state_set | LAB_BS_ROUNDED;
-	if (leftmost_button && leftmost_button->type == b->type) {
-		create_rounded_buffer(theme, LAB_CORNER_TOP_LEFT,
-			&buttons[b->type][rounded_state_set], *buffer);
-	} else if (rightmost_button && rightmost_button->type == b->type) {
-		create_rounded_buffer(theme, LAB_CORNER_TOP_RIGHT,
-			&buttons[b->type][rounded_state_set], *buffer);
-	}
 }
 
 /*