fix: privacy mode 2, restore (#9141)

Signed-off-by: fufesou <linlong1266@gmail.com>

src/server/display_service.rs

@@ -1,4 +1,5 @@
 use super::*;
+use crate::common::SimpleCallOnReturn;
 #[cfg(target_os = "linux")]
 use crate::platform::linux::is_x11;
 #[cfg(windows)]
@@ -7,6 +8,7 @@ use crate::virtual_display_manager;
 use hbb_common::get_version_number;
 use hbb_common::protobuf::MessageField;
 use scrap::Display;
+use std::sync::atomic::{AtomicBool, Ordering};
 
 // https://github.com/rustdesk/rustdesk/discussions/6042, avoiding dbus call
 
@@ -29,6 +31,9 @@ lazy_static::lazy_static! {
     static ref SYNC_DISPLAYS: Arc<Mutex<SyncDisplaysInfo>> = Default::default();
 }
 
+// https://github.com/rustdesk/rustdesk/pull/8537
+static TEMP_IGNORE_DISPLAYS_CHANGED: AtomicBool = AtomicBool::new(false);
+
 #[derive(Default)]
 struct SyncDisplaysInfo {
     displays: Vec<DisplayInfo>,
@@ -39,13 +44,17 @@ impl SyncDisplaysInfo {
     fn check_changed(&mut self, displays: Vec<DisplayInfo>) {
         if self.displays.len() != displays.len() {
             self.displays = displays;
-            self.is_synced = false;
+            if !TEMP_IGNORE_DISPLAYS_CHANGED.load(Ordering::Relaxed) {
+                self.is_synced = false;
+            }
             return;
         }
         for (i, d) in displays.iter().enumerate() {
             if d != &self.displays[i] {
                 self.displays = displays;
-                self.is_synced = false;
+                if !TEMP_IGNORE_DISPLAYS_CHANGED.load(Ordering::Relaxed) {
+                    self.is_synced = false;
+                }
                 return;
             }
         }
@@ -60,6 +69,21 @@ impl SyncDisplaysInfo {
     }
 }
 
+pub fn temp_ignore_displays_changed() -> SimpleCallOnReturn {
+    TEMP_IGNORE_DISPLAYS_CHANGED.store(true, std::sync::atomic::Ordering::Relaxed);
+    SimpleCallOnReturn {
+        b: true,
+        f: Box::new(move || {
+            // Wait for a while to make sure check_display_changed() is called
+            // after video service has sending its `SwitchDisplay` message(`try_broadcast_display_changed()`).
+            std::thread::sleep(Duration::from_millis(1000));
+            TEMP_IGNORE_DISPLAYS_CHANGED.store(false, Ordering::Relaxed);
+            // Trigger the display changed message.
+            SYNC_DISPLAYS.lock().unwrap().is_synced = false;
+        }),
+    }
+}
+
 // This function is really useful, though a duplicate check if display changed.
 // The video server will then send the following messages to the client:
 //  1. the supported resolutions of the {idx} display
@@ -204,9 +228,11 @@ fn get_displays_msg() -> Option<Message> {
 fn run(sp: EmptyExtraFieldService) -> ResultType<()> {
     while sp.ok() {
         sp.snapshot(|sps| {
-            if sps.has_subscribes() {
-                SYNC_DISPLAYS.lock().unwrap().is_synced = false;
-                bail!("new subscriber");
+            if !TEMP_IGNORE_DISPLAYS_CHANGED.load(Ordering::Relaxed) {
+                if sps.has_subscribes() {
+                    SYNC_DISPLAYS.lock().unwrap().is_synced = false;
+                    bail!("new subscriber");
+                }
             }
             Ok(())
         })?;