From 99d8c845f2690a55a6436e31fb0f50a21a285ff0 Mon Sep 17 00:00:00 2001
From: Robin Mueller <muellerr@irs.uni-stuttgart.de>
Date: Mon, 30 Jan 2023 14:05:39 +0100
Subject: [PATCH] allow using SO_REUSEADDR and SO_REUSEPORT on TCP server

---
 src/fsfw/osal/common/TcpTmTcServer.cpp | 15 ++++++++++++---
 src/fsfw/osal/common/TcpTmTcServer.h   | 26 ++++++++++++++++++++------
 2 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/src/fsfw/osal/common/TcpTmTcServer.cpp b/src/fsfw/osal/common/TcpTmTcServer.cpp
index dff959ba..903d8752 100644
--- a/src/fsfw/osal/common/TcpTmTcServer.cpp
+++ b/src/fsfw/osal/common/TcpTmTcServer.cpp
@@ -26,12 +26,12 @@
 const std::string TcpTmTcServer::DEFAULT_SERVER_PORT = tcpip::DEFAULT_SERVER_PORT;
 
 TcpTmTcServer::TcpTmTcServer(object_id_t objectId, object_id_t tmtcTcpBridge,
-                             size_t receptionBufferSize, size_t ringBufferSize,
-                             std::string customTcpServerPort, ReceptionModes receptionMode)
+                             TcpTmTcServer::TcpConfig cfg, size_t receptionBufferSize,
+                             size_t ringBufferSize, ReceptionModes receptionMode)
     : SystemObject(objectId),
       tmtcBridgeId(tmtcTcpBridge),
       receptionMode(receptionMode),
-      tcpConfig(std::move(customTcpServerPort)),
+      tcpConfig(cfg),
       receptionBuffer(receptionBufferSize),
       ringBuffer(ringBufferSize, true) {}
 
@@ -91,6 +91,15 @@ ReturnValue_t TcpTmTcServer::initialize() {
     return returnvalue::FAILED;
   }
 
+  if (tcpConfig.reuseAddr) {
+    unsigned int enable = 1;
+    setsockopt(listenerTcpSocket, SOL_SOCKET, SO_REUSEADDR, &enable, sizeof(enable));
+  }
+  if (tcpConfig.reusePort) {
+    unsigned int enable = 1;
+    setsockopt(listenerTcpSocket, SOL_SOCKET, SO_REUSEPORT, &enable, sizeof(enable));
+  }
+
   // Bind to the address found by getaddrinfo
   retval = bind(listenerTcpSocket, addrResult->ai_addr, static_cast<int>(addrResult->ai_addrlen));
   if (retval == SOCKET_ERROR) {
diff --git a/src/fsfw/osal/common/TcpTmTcServer.h b/src/fsfw/osal/common/TcpTmTcServer.h
index 0e2182a5..8668d845 100644
--- a/src/fsfw/osal/common/TcpTmTcServer.h
+++ b/src/fsfw/osal/common/TcpTmTcServer.h
@@ -41,11 +41,11 @@ class SpacePacketParser;
  */
 class TcpTmTcServer : public SystemObject, public TcpIpBase, public ExecutableObjectIF {
  public:
-  enum class ReceptionModes { SPACE_PACKETS };
-
   struct TcpConfig {
    public:
-    explicit TcpConfig(std::string tcpPort) : tcpPort(std::move(tcpPort)) {}
+    TcpConfig(bool reuseAddr, bool reusePort) : reuseAddr(reuseAddr), reusePort(reusePort) {}
+    TcpConfig(std::string tcpPort, bool reuseAddr, bool reusePort)
+        : tcpPort(std::move(tcpPort)), reuseAddr(reuseAddr), reusePort(reusePort) {}
 
     /**
      * Passed to the recv call
@@ -63,8 +63,23 @@ class TcpTmTcServer : public SystemObject, public TcpIpBase, public ExecutableOb
      */
     int tcpTmFlags = 0;
 
-    const std::string tcpPort;
+    /**
+     * Sets the SO_REUSEADDR option on the socket. See
+     * https://man7.org/linux/man-pages/man7/socket.7.html for more details. This option is
+     * especially useful in a debugging and development environment where an OBSW image might be
+     * re-flashed oftentimes and where all incoming telecommands are received on a dedicated TCP
+     * port.
+     */
+    bool reuseAddr = false;
+    /**
+     * Sets the SO_REUSEPORT option on the socket. See
+     * https://man7.org/linux/man-pages/man7/socket.7.html for more details.
+     */
+    bool reusePort = false;
+
+    std::string tcpPort = DEFAULT_SERVER_PORT;
   };
+  enum class ReceptionModes { SPACE_PACKETS };
 
   static const std::string DEFAULT_SERVER_PORT;
 
@@ -80,10 +95,9 @@ class TcpTmTcServer : public SystemObject, public TcpIpBase, public ExecutableOb
    *                              size will be the Ethernet MTU size
    * @param customTcpServerPort   The user can specify another port than the default (7301) here.
    */
-  TcpTmTcServer(object_id_t objectId, object_id_t tmtcTcpBridge,
+  TcpTmTcServer(object_id_t objectId, object_id_t tmtcTcpBridge, TcpTmTcServer::TcpConfig cfg,
                 size_t receptionBufferSize = RING_BUFFER_SIZE,
                 size_t ringBufferSize = RING_BUFFER_SIZE,
-                std::string customTcpServerPort = DEFAULT_SERVER_PORT,
                 ReceptionModes receptionMode = ReceptionModes::SPACE_PACKETS);
   ~TcpTmTcServer() override;