WIP: Add libcoap CoapUdpIpChannel

.gitmodules

@@ -4,3 +4,6 @@
 [submodule "external/nanopb"]
 	path = external/nanopb
 	url = https://github.com/nanopb/nanopb.git
+[submodule "external/libcoap"]
+	path = external/libcoap
+	url = https://github.com/obgm/libcoap.git

CMakeLists.txt

@@ -47,6 +47,40 @@ set(NANOPB_PATH external/nanopb)
 if (PLATFORM STREQUAL "POSIX")
   add_library(reactor-uc STATIC ${SOURCES})
   target_link_libraries(reactor-uc PRIVATE pthread)
+
+  # Set up options before libcoap is included
+  set(COAP_DISABLE_DTLS ON CACHE BOOL "Disable DTLS" FORCE)
+  set(COAP_BUILD_DOCS OFF CACHE BOOL "Disable docs" FORCE)
+  set(COAP_BUILD_EXAMPLES OFF CACHE BOOL "Disable examples" FORCE)
+  set(COAP_BUILD_TESTS OFF CACHE BOOL "Disable tests" FORCE)
+
+  # Add libcoap as a subdirectory
+  add_subdirectory(external/libcoap)
+
+  # Include internal libcoap headers if needed
+  target_include_directories(reactor-uc PUBLIC
+      external/libcoap/include
+      external/libcoap/src
+  )
+
+  # Link with the libcoap static library
+  target_link_libraries(reactor-uc PRIVATE coap-3)
+
+
+  # TODO: Remove this!
+  # Add Unity as a subdirectory
+  add_subdirectory(external/Unity)
+
+  # Include internal Unity headers if needed
+  target_include_directories(reactor-uc PUBLIC
+      external/Unity/src
+  )
+
+  add_library(Unity STATIC external/Unity/src/unity.c)
+  target_include_directories(Unity PUBLIC ${UNITY_DIR}/src)
+
+  # Link with the Unity static library
+  target_link_libraries(reactor-uc PRIVATE Unity)
 elseif (PLATFORM STREQUAL "FLEXPRET")
   add_library(reactor-uc STATIC ${SOURCES})
   add_subdirectory($ENV{FP_SDK_PATH} BINARY_DIR)
@@ -87,6 +121,10 @@ if(NETWORK_CHANNEL_TCP_POSIX)
   target_compile_definitions(reactor-uc PRIVATE NETWORK_CHANNEL_TCP_POSIX)
 endif()
 
+if(NETWORK_CHANNEL_COAP)
+  target_compile_definitions(reactor-uc PUBLIC NETWORK_CHANNEL_COAP)
+endif()
+
 if(FEDERATED)
   target_compile_definitions(reactor-uc PUBLIC FEDERATED)
 endif()
@@ -109,3 +147,4 @@ if(BUILD_UNIT_TESTS)
   set_target_properties( Unity PROPERTIES C_CLANG_TIDY "") # Disable clang-tidy for this external lib.
   add_subdirectory(test/unit)
 endif()
+

examples/posix/hello/hello.c

@@ -1,5 +1,5 @@
 #include "reactor-uc/reactor-uc.h"
-#include "../../common/timer_source.h" 
+#include "../../common/timer_source.h"
 
 LF_DEFINE_REACTION_BODY(TimerSource, r) {
   LF_SCOPE_SELF(TimerSource);

include/reactor-uc/network_channel.h

@@ -132,6 +132,9 @@ struct AsyncNetworkChannel {
 #ifdef NETWORK_CHANNEL_TCP_POSIX
 #include "platform/posix/tcp_ip_channel.h"
 #endif
+#ifdef NETWORK_CHANNEL_COAP
+#include "platform/posix/coap_udp_ip_channel.h"
+#endif
 
 #elif defined(PLATFORM_ZEPHYR)
 #ifdef NETWORK_CHANNEL_TCP_POSIX

include/reactor-uc/platform/posix/coap_udp_ip_channel.h

@@ -0,0 +1,57 @@
+#ifndef REACTOR_UC_COAP_UDP_IP_CHANNEL_H
+#define REACTOR_UC_COAP_UDP_IP_CHANNEL_H
+#include "reactor-uc/network_channel.h"
+#include "reactor-uc/environment.h"
+#include <pthread.h>
+#include <coap3/coap.h>
+
+#define COAP_UDP_IP_CHANNEL_EXPECTED_CONNECT_DURATION MSEC(10);
+#define COAP_UDP_IP_CHANNEL_BUFFERSIZE 1024
+#define COAP_UDP_IP_CHANNEL_RECV_THREAD_STACK_SIZE 2048
+
+typedef struct CoapUdpIpChannel CoapUdpIpChannel;
+typedef struct FederatedConnectionBundle FederatedConnectionBundle;
+
+typedef enum {
+  COAP_REQUEST_TYPE_NONE,
+  COAP_REQUEST_TYPE_CONNECT,
+  COAP_REQUEST_TYPE_MESSAGE,
+  COAP_REQUEST_TYPE_DISCONNECT
+} coap_request_type_t;
+
+typedef struct CoapUdpIpChannel {
+  NetworkChannel super;
+
+  // Remote address etc.
+  coap_session_t *session;
+
+  // Threading and synchronization
+  pthread_mutex_t state_mutex;
+  pthread_cond_t state_cond;
+  pthread_mutex_t send_mutex;
+  pthread_cond_t send_cond;
+
+  NetworkChannelState state;
+
+  FederateMessage output;
+
+  // Handle message callbacks
+  coap_request_type_t last_request_type;
+  coap_mid_t last_request_mid;
+
+  FederatedConnectionBundle *federated_connection;
+  void (*receive_callback)(FederatedConnectionBundle *conn, const FederateMessage *message);
+} CoapUdpIpChannel;
+
+/**
+ * @brief Constructor for the CoapUdpIpChannel.
+ *
+ * Initializes a CoapUdpIpChannel instance with the specified remote host and protocol family.
+ *
+ * @param self Pointer to the CoapUdpIpChannel instance.
+ * @param remote_host The remote host address, hostname or domain E.g. 127.0.0.1, [::1] or hostname.local.
+ * @param remote_protocol_family The protocol family (e.g., AF_INET for IPv4 and AF_INET6 for IPv6).
+ */
+void CoapUdpIpChannel_ctor(CoapUdpIpChannel *self, const char *remote_host, int remote_protocol_family);
+
+#endif

include/reactor-uc/platform/riot/coap_udp_ip_channel.h

@@ -30,6 +30,15 @@ struct CoapUdpIpChannel {
   void (*receive_callback)(FederatedConnectionBundle *conn, const FederateMessage *message);
 };
 
-void CoapUdpIpChannel_ctor(CoapUdpIpChannel *self, const char *remote_address, int remote_protocol_family);
+/**
+ * @brief Constructor for the CoapUdpIpChannel.
+ *
+ * Initializes a CoapUdpIpChannel instance with the specified remote host and protocol family.
+ *
+ * @param self Pointer to the CoapUdpIpChannel instance.
+ * @param remote_host The remote host address, hostname or domain E.g. 127.0.0.1, [::1] or hostname.local.
+ * @param remote_protocol_family The protocol family (e.g., AF_INET for IPv4 and AF_INET6 for IPv6).
+ */
+void CoapUdpIpChannel_ctor(CoapUdpIpChannel *self, const char *remote_host, int remote_protocol_family);
 
 #endif

src/network_channel.c

@@ -4,6 +4,9 @@
 #ifdef NETWORK_CHANNEL_TCP_POSIX
 #include "platform/posix/tcp_ip_channel.c"
 #endif
+#ifdef NETWORK_CHANNEL_COAP
+#include "platform/posix/coap_udp_ip_channel.c"
+#endif
 
 #elif defined(PLATFORM_ZEPHYR)
 #ifdef NETWORK_CHANNEL_TCP_POSIX