Merge pull request #111639 from timothyqiu/freshy-leaky

X11: Fix memory leak in `screen_get_refresh_rate()`

Author: Repiteo

platform/linuxbsd/x11/display_server_x11.cpp

@@ -1800,59 +1800,57 @@ Ref<Image> DisplayServerX11::screen_get_image(int p_screen) const {
 float DisplayServerX11::screen_get_refresh_rate(int p_screen) const {
 	_THREAD_SAFE_METHOD_
 
+	ERR_FAIL_COND_V_MSG(!xrandr_ext_ok || !xrr_get_monitors, SCREEN_REFRESH_RATE_FALLBACK, "XRandR extension is not available.");
+
 	p_screen = _get_screen_index(p_screen);
 	int screen_count = get_screen_count();
 	ERR_FAIL_INDEX_V(p_screen, screen_count, SCREEN_REFRESH_RATE_FALLBACK);
 
-	//Use xrandr to get screen refresh rate.
-	if (xrandr_ext_ok) {
-		XRRScreenResources *screen_info = XRRGetScreenResourcesCurrent(x11_display, windows[MAIN_WINDOW_ID].x11_window);
-		if (screen_info) {
-			RRMode current_mode = 0;
-			xrr_monitor_info *monitors = nullptr;
-
-			if (xrr_get_monitors) {
-				int count = 0;
-				monitors = xrr_get_monitors(x11_display, windows[MAIN_WINDOW_ID].x11_window, true, &count);
-				ERR_FAIL_INDEX_V(p_screen, count, SCREEN_REFRESH_RATE_FALLBACK);
-			} else {
-				ERR_PRINT("An error occurred while trying to get the screen refresh rate.");
-				return SCREEN_REFRESH_RATE_FALLBACK;
-			}
+	int target_x;
+	int target_y;
+	{
+		int count = 0;
+		xrr_monitor_info *monitors = xrr_get_monitors(x11_display, windows[MAIN_WINDOW_ID].x11_window, true, &count);
+		ERR_FAIL_NULL_V(monitors, SCREEN_REFRESH_RATE_FALLBACK);
+		if (count <= p_screen) {
+			xrr_free_monitors(monitors);
+			ERR_FAIL_V_MSG(SCREEN_REFRESH_RATE_FALLBACK, vformat("Invalid screen index: %d (count: %d).", p_screen, count));
+		}
+		target_x = monitors[p_screen].x;
+		target_y = monitors[p_screen].y;
+		xrr_free_monitors(monitors);
+	}
 
-			bool found_active_mode = false;
-			for (int crtc = 0; crtc < screen_info->ncrtc; crtc++) { // Loop through outputs to find which one is currently outputting.
-				XRRCrtcInfo *monitor_info = XRRGetCrtcInfo(x11_display, screen_info, screen_info->crtcs[crtc]);
-				if (monitor_info->x != monitors[p_screen].x || monitor_info->y != monitors[p_screen].y) { // If X and Y aren't the same as the monitor we're looking for, this isn't the right monitor. Continue.
-					continue;
-				}
+	XRRScreenResources *screen_res = XRRGetScreenResourcesCurrent(x11_display, windows[MAIN_WINDOW_ID].x11_window);
+	ERR_FAIL_NULL_V(screen_res, SCREEN_REFRESH_RATE_FALLBACK);
 
-				if (monitor_info->mode != None) {
-					current_mode = monitor_info->mode;
-					found_active_mode = true;
-					break;
-				}
-			}
-
-			if (found_active_mode) {
-				for (int mode = 0; mode < screen_info->nmode; mode++) {
-					XRRModeInfo m_info = screen_info->modes[mode];
-					if (m_info.id == current_mode) {
-						// Snap to nearest 0.01 to stay consistent with other platforms.
-						return Math::snapped((float)m_info.dotClock / ((float)m_info.hTotal * (float)m_info.vTotal), 0.01);
-					}
-				}
+	XRRModeInfo *mode_info = nullptr;
+	for (int crtc = 0; crtc < screen_res->ncrtc; crtc++) { // Loop through outputs to find which one is currently outputting.
+		XRRCrtcInfo *monitor_info = XRRGetCrtcInfo(x11_display, screen_res, screen_res->crtcs[crtc]);
+		if (monitor_info->x != target_x || monitor_info->y != target_y || monitor_info->mode == None) {
+			XRRFreeCrtcInfo(monitor_info);
+			continue;
+		}
+		for (int mode = 0; mode < screen_res->nmode; mode++) {
+			if (screen_res->modes[mode].id == monitor_info->mode) {
+				mode_info = &screen_res->modes[mode];
 			}
-
-			ERR_PRINT("An error occurred while trying to get the screen refresh rate."); // We should have returned the refresh rate by now. An error must have occurred.
-			return SCREEN_REFRESH_RATE_FALLBACK;
-		} else {
-			ERR_PRINT("An error occurred while trying to get the screen refresh rate.");
-			return SCREEN_REFRESH_RATE_FALLBACK;
 		}
+		XRRFreeCrtcInfo(monitor_info);
+		break;
+	}
+
+	float result;
+	if (mode_info) {
+		// Snap to nearest 0.01 to stay consistent with other platforms.
+		result = Math::snapped((float)mode_info->dotClock / ((float)mode_info->hTotal * (float)mode_info->vTotal), 0.01);
+	} else {
+		ERR_PRINT("An error occurred while trying to get the screen refresh rate.");
+		result = SCREEN_REFRESH_RATE_FALLBACK;
 	}
-	ERR_PRINT("An error occurred while trying to get the screen refresh rate.");
-	return SCREEN_REFRESH_RATE_FALLBACK;
+
+	XRRFreeScreenResources(screen_res);
+	return result;
 }
 
 #ifdef DBUS_ENABLED