feat: insert core entry before launching flutter

flutter/windows/runner/main.cpp

@@ -1,17 +1,41 @@
 #include <flutter/dart_project.h>
 #include <flutter/flutter_view_controller.h>
 #include <windows.h>
+#include <iostream>
 
 #include "flutter_window.h"
 #include "utils.h"
 #include <bitsdojo_window_windows/bitsdojo_window_plugin.h>
 
+typedef bool (*FUNC_RUSTDESK_CORE_MAIN)(void);
+
 auto bdw = bitsdojo_window_configure(BDW_CUSTOM_FRAME | BDW_HIDE_ON_STARTUP);
 int APIENTRY wWinMain(_In_ HINSTANCE instance, _In_opt_ HINSTANCE prev,
-                      _In_ wchar_t *command_line, _In_ int show_command) {
+                      _In_ wchar_t *command_line, _In_ int show_command)
+{
+  HINSTANCE hInstance = LoadLibraryA("librustdesk.dll");
+  if (!hInstance)
+  {
+    std::cout << "Failed to load librustdesk.dll" << std::endl;
+    return EXIT_FAILURE;
+  }
+  FUNC_RUSTDESK_CORE_MAIN rustdesk_core_main =
+      (FUNC_RUSTDESK_CORE_MAIN)GetProcAddress(hInstance, "rustdesk_core_main");
+  if (!rustdesk_core_main)
+  {
+    std::cout << "Failed to get rustdesk_core_main" << std::endl;
+    return EXIT_FAILURE;
+  }
+  if (!rustdesk_core_main())
+  {
+    std::cout << "Rustdesk core returns false, exiting without launching Flutter app" << std::endl;
+    return EXIT_SUCCESS;
+  }
+
   // Attach to console when present (e.g., 'flutter run') or create a
   // new console when running with a debugger.
-  if (!::AttachConsole(ATTACH_PARENT_PROCESS) && ::IsDebuggerPresent()) {
+  if (!::AttachConsole(ATTACH_PARENT_PROCESS) && ::IsDebuggerPresent())
+  {
     CreateAndAttachConsole();
   }
 
@@ -29,13 +53,15 @@ int APIENTRY wWinMain(_In_ HINSTANCE instance, _In_opt_ HINSTANCE prev,
   FlutterWindow window(project);
   Win32Window::Point origin(10, 10);
   Win32Window::Size size(1280, 720);
-  if (!window.CreateAndShow(L"flutter_hbb", origin, size)) {
+  if (!window.CreateAndShow(L"flutter_hbb", origin, size))
+  {
     return EXIT_FAILURE;
   }
   window.SetQuitOnClose(true);
 
   ::MSG msg;
-  while (::GetMessage(&msg, nullptr, 0, 0)) {
+  while (::GetMessage(&msg, nullptr, 0, 0))
+  {
     ::TranslateMessage(&msg);
     ::DispatchMessage(&msg);
   }

src/core_main.rs

@@ -0,0 +1,13 @@
+/// Main entry of the RustDesk Core.
+/// Return true if the app should continue running with UI(possibly Flutter), false if the app should exit.
+pub fn core_main() -> bool {
+    let args = std::env::args().collect::<Vec<_>>();
+    // TODO: implement core_main()
+    if args.len() > 1 {
+        if args[1] == "--cm" {
+            // For test purpose only, this should stop any new window from popping up when a new connection is established.
+            return false;
+        }
+    }
+    true
+}

src/flutter_ffi.rs

@@ -52,6 +52,13 @@ fn initialize(app_dir: &str) {
     }
 }
 
+/// FFI for rustdesk core's main entry.
+/// Return true if the app should continue running with UI(possibly Flutter), false if the app should exit.
+#[no_mangle]
+pub extern "C" fn rustdesk_core_main() -> bool {
+    crate::core_main::core_main()
+}
+
 pub fn start_event_stream(s: StreamSink<String>) -> ResultType<()> {
     let _ = flutter::EVENT_STREAM.write().unwrap().insert(s);
     Ok(())

src/lib.rs

@@ -28,6 +28,11 @@ pub mod flutter;
 #[cfg(any(target_os = "android", target_os = "ios", feature = "flutter"))]
 pub mod flutter_ffi;
 use common::*;
+#[cfg(all(
+    not(any(target_os = "android", target_os = "ios")),
+    feature = "flutter"
+))]
+pub mod core_main;
 #[cfg(feature = "cli")]
 pub mod cli;
 #[cfg(all(windows, feature = "hbbs"))]