From 6e6af01b7a1f2ff1a35f7751c07e51277d4414e2 Mon Sep 17 00:00:00 2001
From: Michael Stapelberg <michael@stapelberg.de>
Date: Thu, 3 Nov 2022 23:02:19 +0100
Subject: [PATCH] draw_util: refactor surface_initialized macro into function

This makes it possible to set a breakpoint in gdb on a line in the function and
get a backtrace of un-initialized surface access.
---
 libi3/draw_util.c | 40 ++++++++++++++++++++++++++--------------
 1 file changed, 26 insertions(+), 14 deletions(-)

diff --git a/libi3/draw_util.c b/libi3/draw_util.c
index 30eae656..903e3536 100644
--- a/libi3/draw_util.c
+++ b/libi3/draw_util.c
@@ -20,13 +20,13 @@ extern xcb_visualtype_t *visual_type;
 /* Forward declarations */
 static void draw_util_set_source_color(surface_t *surface, color_t color);
 
-#define RETURN_UNLESS_SURFACE_INITIALIZED(surface)                               \
-    do {                                                                         \
-        if ((surface)->id == XCB_NONE) {                                         \
-            ELOG("Surface %p is not initialized, skipping drawing.\n", surface); \
-            return;                                                              \
-        }                                                                        \
-    } while (0)
+static bool surface_initialized(surface_t *surface) {
+    if (surface->id == XCB_NONE) {
+        ELOG("Surface %p is not initialized, skipping drawing.\n", surface);
+        return false;
+    }
+    return true;
+}
 
 /*
  * Initialize the surface to represent the given drawable.
@@ -131,7 +131,9 @@ color_t draw_util_hex_to_color(const char *color) {
  *
  */
 static void draw_util_set_source_color(surface_t *surface, color_t color) {
-    RETURN_UNLESS_SURFACE_INITIALIZED(surface);
+    if (!surface_initialized(surface)) {
+        return;
+    }
 
     cairo_set_source_rgba(surface->cr, color.red, color.green, color.blue, color.alpha);
 }
@@ -143,7 +145,9 @@ static void draw_util_set_source_color(surface_t *surface, color_t color) {
  *
  */
 void draw_util_text(i3String *text, surface_t *surface, color_t fg_color, color_t bg_color, int x, int y, int max_width) {
-    RETURN_UNLESS_SURFACE_INITIALIZED(surface);
+    if (!surface_initialized(surface)) {
+        return;
+    }
 
     /* Flush any changes before we draw the text as this might use XCB directly. */
     CAIRO_SURFACE_FLUSH(surface->surface);
@@ -162,7 +166,9 @@ void draw_util_text(i3String *text, surface_t *surface, color_t fg_color, color_
  *
  */
 void draw_util_image(cairo_surface_t *image, surface_t *surface, int x, int y, int width, int height) {
-    RETURN_UNLESS_SURFACE_INITIALIZED(surface);
+    if (!surface_initialized(surface)) {
+        return;
+    }
 
     cairo_save(surface->cr);
 
@@ -186,7 +192,9 @@ void draw_util_image(cairo_surface_t *image, surface_t *surface, int x, int y, i
  *
  */
 void draw_util_rectangle(surface_t *surface, color_t color, double x, double y, double w, double h) {
-    RETURN_UNLESS_SURFACE_INITIALIZED(surface);
+    if (!surface_initialized(surface)) {
+        return;
+    }
 
     cairo_save(surface->cr);
 
@@ -211,7 +219,9 @@ void draw_util_rectangle(surface_t *surface, color_t color, double x, double y,
  *
  */
 void draw_util_clear_surface(surface_t *surface, color_t color) {
-    RETURN_UNLESS_SURFACE_INITIALIZED(surface);
+    if (!surface_initialized(surface)) {
+        return;
+    }
 
     cairo_save(surface->cr);
 
@@ -236,8 +246,10 @@ void draw_util_clear_surface(surface_t *surface, color_t color) {
  */
 void draw_util_copy_surface(surface_t *src, surface_t *dest, double src_x, double src_y,
                             double dest_x, double dest_y, double width, double height) {
-    RETURN_UNLESS_SURFACE_INITIALIZED(src);
-    RETURN_UNLESS_SURFACE_INITIALIZED(dest);
+    if (!surface_initialized(src) ||
+        !surface_initialized(dest)) {
+        return;
+    }
 
     cairo_save(dest->cr);