[optimize] Packet Decode

1. Add a macro to obtain Packet’s encapsulation information (the returned data is an immutable reference to Packet)
    * get_innermost_special_encapsulation!()
    * get_outermost_special_encapsulation!()

    Example: let icmp_encapsulation : Option<&Encapsulation> = get_innermost_special_encapsulation!(&Packet, ICMP);
    Example: let l4_encapsulation   : Option<&Encapsulation> = get_innermost_special_encapsulation!(&Packet, TCP | UDP);

2. Clean up the Clone/Copy Trait of PacketDecode to avoid memory copies caused by improper use by users.

1 files changed, 10 insertions, 10 deletions

diff --git a/src/session/session.rs b/src/session/session.rs
index e8b2be4..1db4bfd 100644
--- a/src/session/session.rs
+++ b/src/session/session.rs
@@ -7,19 +7,19 @@ use std::collections::HashMap;
 
 const MAX_SESSION_EXPIRE_TIME: i64 = 60;
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum SessionDirection {
     C2S,
     S2C,
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum SessionProto {
     TCP,
     UDP,
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, PartialEq)]
 pub enum SessionState {
     New,
     Active,
@@ -27,7 +27,7 @@ pub enum SessionState {
     Expired,
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[derive(Debug)]
 pub struct SessionMetrics {
     pub send_pkts: u64,
     pub send_bytes: u64,
@@ -35,7 +35,7 @@ pub struct SessionMetrics {
     pub recv_bytes: u64,
 }
 
-#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+#[derive(Debug)]
 struct SessionTimeStamp {
     ts_start: i64,
     ts_end: i64,
@@ -49,7 +49,7 @@ struct SessionTimeStamp {
  *  - if current packet is iterm of session, require packet lifetime > session lifetime
  ******************************************************************************/
 
-#[derive(Clone, Debug, PartialEq, Eq)]
+#[derive(Debug)]
 pub struct Session {
     session_id: String,
     session_proto: SessionProto,
@@ -132,8 +132,8 @@ impl Session {
         self.session_metrics_c2s.recv_bytes += recv_bytes;
     }
 
-    pub fn get_session_c2s_metrics(&self) -> SessionMetrics {
-        self.session_metrics_c2s
+    pub fn get_session_c2s_metrics(&self) -> &SessionMetrics {
+        &self.session_metrics_c2s
     }
 
     pub fn inc_session_s2c_metrics(
@@ -149,8 +149,8 @@ impl Session {
         self.session_metrics_s2c.recv_bytes += recv_bytes;
     }
 
-    pub fn get_session_s2c_metrics(&self) -> SessionMetrics {
-        self.session_metrics_s2c
+    pub fn get_session_s2c_metrics(&self) -> &SessionMetrics {
+        &self.session_metrics_s2c
     }
 
     pub fn update_session_expire_ts(&mut self) {