beginning async version (#84)

src/proxy_handler.rs

@@ -0,0 +1,30 @@
+use crate::{
+    directions::{IncomingDataEvent, OutgoingDataEvent, OutgoingDirection},
+    session_info::SessionInfo,
+};
+use std::{net::SocketAddr, sync::Arc};
+use tokio::sync::Mutex;
+
+#[async_trait::async_trait]
+pub(crate) trait ProxyHandler: Send + Sync {
+    fn get_session_info(&self) -> SessionInfo;
+    fn get_domain_name(&self) -> Option<String>;
+    async fn push_data(&mut self, event: IncomingDataEvent<'_>) -> std::io::Result<()>;
+    fn consume_data(&mut self, dir: OutgoingDirection, size: usize);
+    fn peek_data(&mut self, dir: OutgoingDirection) -> OutgoingDataEvent;
+    fn connection_established(&self) -> bool;
+    fn data_len(&self, dir: OutgoingDirection) -> usize;
+    fn reset_connection(&self) -> bool;
+    fn get_udp_associate(&self) -> Option<SocketAddr>;
+}
+
+#[async_trait::async_trait]
+pub(crate) trait ProxyHandlerManager: Send + Sync {
+    async fn new_proxy_handler(
+        &self,
+        info: SessionInfo,
+        domain_name: Option<String>,
+        udp_associate: bool,
+    ) -> std::io::Result<Arc<Mutex<dyn ProxyHandler>>>;
+    fn get_server_addr(&self) -> SocketAddr;
+}