add packet_len direct method for SpHeader

src/lib.rs

@@ -302,6 +302,7 @@ pub trait CcsdsPacket {
 
     /// Retrieve data length field
     fn data_len(&self) -> u16;
+
     /// Retrieve the total packet size based on the data length field
     #[inline]
     fn packet_len(&self) -> usize {
@@ -504,6 +505,12 @@ impl SpHeader {
         }
     }
 
+    /// Retrieve the total packet size based on the data length field
+    #[inline]
+    fn packet_len(&self) -> usize {
+        usize::from(self.data_len()) + CCSDS_HEADER_LEN + 1
+    }
+
     #[inline]
     pub fn set_seq_count(&mut self, seq_count: u14) {
         self.psc.seq_count = seq_count;