refactor: improve the code

.vscode/settings.json

@@ -20,6 +20,7 @@
     "stdio.h": "c",
     "openconnect.h": "c",
     "compare": "c",
-    "stdlib.h": "c"
+    "stdlib.h": "c",
+    "vpn.h": "c"
   }
 }

common/src/vpn/ffi.rs

@@ -1,4 +1,5 @@
 use std::ffi::c_void;
+use tokio::sync::mpsc;
 
 #[repr(C)]
 #[derive(Debug, Copy, Clone)]
@@ -12,11 +13,24 @@ pub(crate) struct Options {
 #[link(name = "vpn")]
 extern "C" {
     #[link_name = "start"]
-    pub(crate) fn connect(
-        options: *const Options,
-        on_connected: extern "C" fn(i32, *mut c_void),
-    ) -> ::std::os::raw::c_int;
+    pub(crate) fn connect(options: *const Options) -> ::std::os::raw::c_int;
 
     #[link_name = "stop"]
     pub(crate) fn disconnect();
 }
+
+#[no_mangle]
+extern "C" fn on_vpn_connected(value: i32, sender: *mut c_void) {
+    let sender = unsafe { &*(sender as *const mpsc::Sender<i32>) };
+    sender
+        .blocking_send(value)
+        .expect("Failed to send VPN connection code");
+}
+
+// Logger used in the C code.
+#[no_mangle]
+extern "C" fn vpn_log(level: i32, message: *const ::std::os::raw::c_char) {
+    println!("{}: {:?}", level, unsafe {
+        std::ffi::CStr::from_ptr(message)
+    });
+}

common/src/vpn/mod.rs

@@ -1,5 +1,3 @@
-mod ffi;
-
 use serde::{Deserialize, Serialize};
 use std::ffi::{c_void, CString};
 use std::sync::Arc;
@@ -7,13 +5,7 @@ use std::thread;
 use tokio::sync::watch;
 use tokio::sync::{mpsc, Mutex};
 
-#[no_mangle]
-extern "C" fn on_connected(value: i32, sender: *mut c_void) {
-    let sender = unsafe { &*(sender as *const mpsc::Sender<i32>) };
-    sender
-        .blocking_send(value)
-        .expect("Failed to send VPN connection code");
-}
+mod ffi;
 
 #[derive(Debug, PartialEq, Clone, Copy, Serialize, Deserialize)]
 #[serde(rename_all = "lowercase")]
@@ -119,7 +111,7 @@ impl Vpn {
 
             // Start the VPN connection, this will block until the connection is closed
             status_holder.blocking_lock().set(VpnStatus::Connecting);
-            let ret = unsafe { ffi::connect(&oc_options, on_connected) };
+            let ret = unsafe { ffi::connect(&oc_options) };
 
             println!("VPN connection closed with code: {}", ret);
             status_holder.blocking_lock().set(VpnStatus::Disconnected);

common/src/vpn/vpn.c

@@ -9,7 +9,6 @@
 #include "vpn.h"
 
 void *g_user_data;
-on_connected_cb g_on_connected_cb;
 
 static int g_cmd_pipe_fd;
 const char *g_vpnc_script;
@@ -43,19 +42,18 @@ static void print_progress(__attribute__((unused)) void *_vpninfo, int level, co
 static void setup_tun_handler(void *_vpninfo)
 {
     openconnect_setup_tun_device(_vpninfo, g_vpnc_script, NULL);
-
-    if (g_on_connected_cb)
-    {
-        g_on_connected_cb(g_cmd_pipe_fd, g_user_data);
-    }
+    on_vpn_connected(g_cmd_pipe_fd, g_user_data);
 }
 
 /* Initialize VPN connection */
-int start(const Options *options, on_connected_cb cb)
+int start(const Options *options)
 {
     struct openconnect_info *vpninfo;
     struct utsname utsbuf;
 
+    g_user_data = options->user_data;
+    g_vpnc_script = options->script;
+
     vpninfo = openconnect_vpninfo_new("PAN GlobalProtect", validate_peer_cert, NULL, NULL, print_progress, NULL);
 
     if (!vpninfo)
@@ -95,10 +93,6 @@ int start(const Options *options, on_connected_cb cb)
     }
 
     // Essential step
-    // openconnect_setup_tun_device(vpninfo, options->script, NULL);
-    g_user_data = options->user_data;
-    g_on_connected_cb = cb;
-    g_vpnc_script = options->script;
     openconnect_set_setup_tun_handler(vpninfo, setup_tun_handler);
 
     while (1)

common/src/vpn/vpn.h

@@ -1,5 +1,3 @@
-typedef void (*on_connected_cb)(int32_t, void *);
-
 typedef struct Options {
   const char *server;
   const char *cookie;
@@ -7,5 +5,8 @@ typedef struct Options {
   void *user_data;
 } Options;
 
-int start(const Options *options, on_connected_cb cb);
+int start(const Options *options);
 void stop();
+
+extern void on_vpn_connected(int cmd_pipe_fd, void *user_data);
+extern void vpn_log(int level, const char *msg);