From 1af5601d633cdd37b9eb89d2cacec13502b58416 Mon Sep 17 00:00:00 2001
From: Robin Mueller <robin.mueller.m@gmail.com>
Date: Fri, 15 Sep 2023 19:22:12 +0200
Subject: [PATCH] looking good

---
 satrs-core/src/hal/host/mod.rs                  |  2 +-
 satrs-core/src/hal/host/tcp_server.rs           | 14 ++++++++------
 satrs-core/src/hal/host/tcp_with_cobs_server.rs | 15 ++++++++++++++-
 3 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/satrs-core/src/hal/host/mod.rs b/satrs-core/src/hal/host/mod.rs
index dfd02c1..5e98061 100644
--- a/satrs-core/src/hal/host/mod.rs
+++ b/satrs-core/src/hal/host/mod.rs
@@ -1,4 +1,4 @@
 //! Helper modules intended to be used on hosts with a full [std] runtime
-mod tcp_with_cobs_server;
 pub mod tcp_server;
+mod tcp_with_cobs_server;
 pub mod udp_server;
diff --git a/satrs-core/src/hal/host/tcp_server.rs b/satrs-core/src/hal/host/tcp_server.rs
index 16bcce4..c518bad 100644
--- a/satrs-core/src/hal/host/tcp_server.rs
+++ b/satrs-core/src/hal/host/tcp_server.rs
@@ -8,7 +8,9 @@ use core::fmt::Display;
 use thiserror::Error;
 
 // Re-export the TMTC in COBS server.
-pub use crate::hal::host::tcp_with_cobs_server::TcpTmtcInCobsServer;
+pub use crate::hal::host::tcp_with_cobs_server::{
+    parse_buffer_for_cobs_encoded_packets, TcpTmtcInCobsServer,
+};
 
 #[derive(Error, Debug)]
 pub enum TcpTmtcError<TmError: Display, TcError: Display> {
@@ -30,11 +32,11 @@ pub struct ConnectionResult {
 }
 
 pub(crate) struct TcpTmtcServerBase<TcError, TmError> {
-    pub (crate) listener: TcpListener,
-    pub (crate) tm_source: Box<dyn TmPacketSource<Error = TmError>>,
-    pub (crate) tm_buffer: Vec<u8>,
-    pub (crate) tc_receiver: Box<dyn ReceivesTc<Error = TcError>>,
-    pub (crate) tc_buffer: Vec<u8>,
+    pub(crate) listener: TcpListener,
+    pub(crate) tm_source: Box<dyn TmPacketSource<Error = TmError>>,
+    pub(crate) tm_buffer: Vec<u8>,
+    pub(crate) tc_receiver: Box<dyn ReceivesTc<Error = TcError>>,
+    pub(crate) tc_buffer: Vec<u8>,
 }
 
 impl<TcError, TmError> TcpTmtcServerBase<TcError, TmError> {
diff --git a/satrs-core/src/hal/host/tcp_with_cobs_server.rs b/satrs-core/src/hal/host/tcp_with_cobs_server.rs
index 6c72254..359eec3 100644
--- a/satrs-core/src/hal/host/tcp_with_cobs_server.rs
+++ b/satrs-core/src/hal/host/tcp_with_cobs_server.rs
@@ -9,9 +9,9 @@ use std::io::Write;
 use std::net::ToSocketAddrs;
 use std::vec::Vec;
 
+use crate::hal::host::tcp_server::TcpTmtcServerBase;
 use crate::tmtc::ReceivesTc;
 use crate::tmtc::TmPacketSource;
-use crate::hal::host::tcp_server::TcpTmtcServerBase;
 
 use super::tcp_server::ConnectionResult;
 use super::tcp_server::TcpTmtcError;
@@ -22,6 +22,9 @@ use super::tcp_server::TcpTmtcError;
 /// Using a framing protocol like COBS imposes minimal restrictions on the type of TMTC data
 /// exchanged while also allowing packets with flexible size and a reliable way to reconstruct full
 /// packets even from a data stream which is split up.
+///
+/// The server wil use the [parse_buffer_for_cobs_encoded_packets] function to parse for packets
+/// and pass them to a generic TC receiver.
 pub struct TcpTmtcInCobsServer<TcError, TmError> {
     base: TcpTmtcServerBase<TcError, TmError>,
     tm_encoding_buffer: Vec<u8>,
@@ -112,6 +115,16 @@ impl<TcError: 'static + Display, TmError: 'static + Display> TcpTmtcInCobsServer
     }
 }
 
+/// This function parses a given buffer for COBS encoded packets. The packet structure is
+/// expected to be like this, assuming a sentinel value of 0 as the packet delimiter.
+///
+/// 0 | ... Packet Data ... | 0 | 0 | ... Packet Data ... | 0
+///
+/// This function is also able to deal with broken tail packets at the end. If broken tail
+/// packets are detected, they are moved to the front of the buffer, and the write index for
+/// future write operations will be written to the `next_write_idx` argument.
+///
+/// The parser will write all packets which were decoded successfully to the given `tc_receiver`.
 pub fn parse_buffer_for_cobs_encoded_packets<E>(
     buf: &mut [u8],
     tc_receiver: &mut dyn ReceivesTc<Error = E>,