refactor!: always close second instances

Always close second instances and remove the ability to to close them manually
we can bring it later if it is needed

examples/vanilla/src-tauri/src/main.rs

@@ -5,12 +5,9 @@
 
 fn main() {
   tauri::Builder::default()
-    .plugin(tauri_plugin_single_instance::init(
-      |argv, cwd, close_new_instance| {
-        println!("{argv:?}, {cwd}");
-        close_new_instance();
-      },
-    ))
+    .plugin(tauri_plugin_single_instance::init(|argv, cwd| {
+      println!("{argv:?}, {cwd}");
+    }))
     .run(tauri::generate_context!())
     .expect("error while running tauri application");
 }

src/lib.rs

@@ -10,13 +10,9 @@ mod platform_impl;
 #[path = "platform_impl/macos.rs"]
 mod platform_impl;
 
-pub(crate) type SingleInstanceCallback =
-    dyn FnMut(Vec<String>, String, Box<dyn FnOnce()>) + Send + Sync + 'static;
+pub(crate) type SingleInstanceCallback = dyn FnMut(Vec<String>, String) + Send + Sync + 'static;
 
-pub fn init<
-    R: Runtime,
-    F: FnMut(Vec<String>, String, Box<dyn FnOnce()>) + Send + Sync + 'static,
->(
+pub fn init<R: Runtime, F: FnMut(Vec<String>, String) + Send + Sync + 'static>(
     f: F,
 ) -> TauriPlugin<R> {
     platform_impl::init(Box::new(f))

src/platform_impl/linux.rs

@@ -1,7 +1,6 @@
 #![cfg(target_os = "linux")]
 
 use crate::SingleInstanceCallback;
-use std::{cell::RefCell, rc::Rc};
 use tauri::{
     plugin::{self, TauriPlugin},
     Manager, RunEvent, Runtime,
@@ -12,7 +11,6 @@ use zbus::{
 };
 
 struct ConnectionHandle(Connection);
-const CLOSE_NEW_INSTANCE_ID: u32 = 1542;
 
 struct SingleInstanceDBus {
     callback: Box<SingleInstanceCallback>,
@@ -20,19 +18,8 @@ struct SingleInstanceDBus {
 
 #[dbus_interface(name = "org.SingleInstance.DBus")]
 impl SingleInstanceDBus {
-    fn execute_callback(&mut self, argv: Vec<String>, cwd: String) -> u32 {
-        let ret = Rc::new(RefCell::new(1));
-        let ret_c = Rc::clone(&ret);
-
-        (self.callback)(
-            argv,
-            cwd,
-            Box::new(move || {
-                let mut ret = ret_c.borrow_mut();
-                *ret = CLOSE_NEW_INSTANCE_ID;
-            }),
-        );
-        ret.take()
+    fn execute_callback(&mut self, argv: Vec<String>, cwd: String) {
+        (self.callback)(argv, cwd);
     }
 }
 
@@ -56,25 +43,22 @@ pub fn init<R: Runtime>(f: Box<SingleInstanceCallback>) -> TauriPlugin<R> {
                     app.manage(ConnectionHandle(connection));
                 }
                 Err(zbus::Error::NameTaken) => {
-                    let connection = Connection::session().unwrap();
-                    if let Ok(m) = connection.call_method(
-                        Some(dbus_name.as_str()),
-                        dbus_path.as_str(),
-                        Some("org.SingleInstance.DBus"),
-                        "ExecuteCallback",
-                        &(
-                            std::env::args().collect::<Vec<String>>(),
-                            std::env::current_dir()
-                                .unwrap_or_default()
-                                .to_str()
-                                .unwrap_or_default(),
-                        ),
-                    ) {
-                        let reply: u32 = m.body().unwrap_or_default();
-                        if reply == CLOSE_NEW_INSTANCE_ID {
-                            std::process::exit(0);
-                        }
+                    if let Ok(connection) = Connection::session() {
+                        let _ = connection.call_method(
+                            Some(dbus_name.as_str()),
+                            dbus_path.as_str(),
+                            Some("org.SingleInstance.DBus"),
+                            "ExecuteCallback",
+                            &(
+                                std::env::args().collect::<Vec<String>>(),
+                                std::env::current_dir()
+                                    .unwrap_or_default()
+                                    .to_str()
+                                    .unwrap_or_default(),
+                            ),
+                        );
                     }
+                    std::process::exit(0)
                 }
                 _ => {}
             }

src/platform_impl/windows.rs

@@ -1,7 +1,7 @@
 #![cfg(target_os = "windows")]
 
 use crate::SingleInstanceCallback;
-use std::{cell::RefCell, ffi::CStr, rc::Rc};
+use std::ffi::CStr;
 use tauri::{
     plugin::{self, TauriPlugin},
     Manager, RunEvent, Runtime,
@@ -25,7 +25,6 @@ struct MutexHandle(isize);
 struct TargetWindowHandle(isize);
 
 const WMCOPYDATA_SINGLE_INSTANCE_DATA: usize = 1542;
-const CLOSE_NEW_INSTANCE_ID: isize = 1542;
 
 pub fn init<R: Runtime>(f: Box<SingleInstanceCallback>) -> TauriPlugin<R> {
     plugin::Builder::new("single-instance")
@@ -64,10 +63,8 @@ pub fn init<R: Runtime>(f: Box<SingleInstanceCallback>) -> TauriPlugin<R> {
                             cbData: bytes.len() as _,
                             lpData: bytes.as_ptr() as _,
                         };
-                        let ret = SendMessageW(hwnd, WM_COPYDATA, 0, &cds as *const _ as _);
-                        if ret == CLOSE_NEW_INSTANCE_ID {
-                            std::process::exit(0);
-                        }
+                        SendMessageW(hwnd, WM_COPYDATA, 0, &cds as *const _ as _);
+                        std::process::exit(0);
                     }
                 }
             } else {
@@ -107,25 +104,15 @@ unsafe extern "system" fn single_instance_window_proc(
 
     match msg {
         WM_COPYDATA => {
-            let ret = Rc::new(RefCell::new(1));
-
             let cds_ptr = lparam as *const COPYDATASTRUCT;
             if (*cds_ptr).dwData == WMCOPYDATA_SINGLE_INSTANCE_DATA {
                 let data = CStr::from_ptr((*cds_ptr).lpData as _).to_string_lossy();
                 let mut s = data.split("|");
                 let cwd = s.next().unwrap();
                 let args = s.into_iter().map(|s| s.to_string()).collect();
-                let ret_c = Rc::clone(&ret);
-                (*callback_ptr)(
-                    args,
-                    cwd.to_string(),
-                    Box::new(move || {
-                        let mut ret = ret_c.borrow_mut();
-                        *ret = CLOSE_NEW_INSTANCE_ID;
-                    }),
-                );
+                (*callback_ptr)(args, cwd.to_string());
             }
-            ret.take()
+            1
         }
 
         WM_DESTROY => {