Add RIOT examples (#63)

* Add RIOT examples

* fixup! Add RIOT examples

Fix example makefiles

* fixup! Add RIOT examples

Add RIOT networking modules to example makefiles

* fixup! Add RIOT examples

Add RIOT pthread module to examples

* fixup! Add RIOT examples

Remove -Wcast-align CFLAG to make reactor-uc build for RIOT

* fixup! Add RIOT examples

Fix examples to build for all boards

* fixup! Add RIOT examples

Remove -Wstrict-prototypes and -Wold-style-definition CFLAG to make reactor-uc build for RIOT

* fixup! Add RIOT examples

Migrate blinky example to macros

* Automatically enable RIOT modules if NETWORK_POSIX_TCP is defined

* Update readme: Add RIOT examples tutorial

* Fix RIOT pthread wrapper compatibility

* Remove tcp test riot examples

* Fix riot blinky example

* Add RIOT hello example

README.md

@@ -1,4 +1,5 @@
 # reactor-uc
+
 `reactor-uc` is a task scheduling runtime implementing the reactor
 model-of-computation target at embedded and resource-constrained 32 bit systems.
 
@@ -8,21 +9,25 @@ NB: reactor-uc is still work-in-progress and many (most?) features are not suppo
 yet. This only documents how to run a few example programs.
 
 Setup the environment
+
 ```
 source env.bash
 ```
 
 Initialize submodules
+
 ```
 git submodule update --init
 ```
 
 Compile and run unit tests:
+
 ```
 make test
 ```
 
 Compile and run a simple timer test on Posix
+
 ```
 cd examples/posix
 cmake -Bbuild
@@ -45,10 +50,20 @@ west build -b frdm_k64f -p always
 west flash
 ```
 
-For more information on running LF programs using the reactor-uc runtime on 
-Zephyr take a look at this template: https://github.com/lf-lang/lf-west-template/tree/reactor-uc
+Compile and run a simple blinky example on RIOT.
+This requires a correctly configured RIOT environment.
+Make sure that the environment variable `RIOTBASE` points to a `RIOT` codebase.
+
+```
+cd examples/riot/blinky
+make BOARD=native all term
+```
+
+For more information on running LF programs using the reactor-uc runtime on
+Zephyr take a look at this template: <https://github.com/lf-lang/lf-west-template/tree/reactor-uc>
 
 ## Lingua Franca
+
 We have copied a very limited version of the Lingua Franca Compiler (lfc) into
 `~/lfc` of this repo. In the future, the `reactor-uc` specific code-generation
 will be merged back upstream. By sourcing `env.bash` or `env.fish` the Lingua
@@ -69,6 +84,7 @@ bin/HelloUc
 ```
 
 ## Goals
+
 - Incorporate unit testing and test-driven development from the start
 - Optimized for single-core 32-bit systems
 - Backend for LF
@@ -80,13 +96,16 @@ which enable distributed embedded systems.
 - Avoid malloc as much as possible (or entirely?)
 
 ## References
+
 `reactor-uc` draws inspiration from the following existing open-source projects:
+
 - [reactor-cpp](https://github.com/lf-lang/reactor-cpp)
 - [reactor-c](https://github.com/lf-lang/reactor-c)
 - [qpc](https://github.com/QuantumLeaps/qpc)
 - [ssm-runtime](https://github.com/QuantumLeaps/qpc)
 
-## TODO for the MVP:
+## TODO for the MVP
+
 - [x] Timers
 - [x] Input/Output Ports
 - [x] Logical Actions
@@ -99,8 +118,8 @@ which enable distributed embedded systems.
 - [x] Posix Platform abstractions
 - [x] Basic code-generation
 
-
 ## More advanced topics
+
 - [x] More platform abstractions (Riot, Zephyr and FlexPRET/InterPRET)
 - [x] Reconsider where to buffer data (outputs vs inputs)
 - [x] Consider if we should have FIFOs of pending events, not just a single for a trigger.
@@ -111,20 +130,20 @@ which enable distributed embedded systems.
 - [ ] Multiports and banks
 - [ ] Modal reactors
 
-
 ## Troubleshooting
 
 ### Formatting
+
 We are using `clang-format` version 18.1.3 which is default with Ubuntu 24.04 for formatting in CI.
 
 ### LFC
 
 If you get the following CMake error when calling `lfc/bin/lfc-dev`
+
 ```
 CMake Error at CMakeLists.txt:7 (message):
   Environment variable REACTOR_UC_PATH is not set.  Please source the
   env.bash in reactor-uc.
 ```
 
-Please source `env.bash` or `env.fish`. 
-
+Please source `env.bash` or `env.fish`.

examples/riot/blinky/Makefile

@@ -0,0 +1,18 @@
+# name of your application
+APPLICATION = lf-test
+
+# If no BOARD is found in the environment, use this default:
+BOARD ?= native
+
+# Comment this out to disable code in RIOT that does safety checking
+# which is not needed in a production environment but helps in the
+# development process:
+DEVELHELP ?= 1
+
+# Change this to 0 show compiler invocation lines by default:
+QUIET ?= 1
+
+# Enable reactor-uc features
+# CFLAGS += -DNETWORK_POSIX_TCP
+
+include $(CURDIR)/../../../make/riot/riot.mk

examples/riot/blinky/main.c

@@ -0,0 +1,37 @@
+#include "board.h"
+#include "reactor-uc/reactor-uc.h"
+#include <inttypes.h>
+
+DEFINE_TIMER(MyTimer, 1, MSEC(0), MSEC(100))
+DEFINE_REACTION(MyReactor, 0, 0)
+
+typedef struct {
+  Reactor super;
+  MyReactor_0 my_reaction;
+  MyTimer timer;
+  Reaction *_reactions[1];
+  Trigger *_triggers[1];
+} MyReactor;
+
+REACTION_BODY(MyReactor, 0, {
+  LED0_TOGGLE;
+  printf("Hello World @ %" PRId64 "\n", env->get_elapsed_physical_time(env));
+})
+
+void MyReactor_ctor(MyReactor *self, Environment *env) {
+  self->_reactions[0] = (Reaction *)&self->my_reaction;
+  self->_triggers[0] = (Trigger *)&self->timer;
+
+  Reactor_ctor(&self->super, "MyReactor", env, NULL, NULL, 0, self->_reactions, 1, self->_triggers, 1);
+  MyReactor_0_ctor(&self->my_reaction, &self->super);
+  MyTimer_ctor(&self->timer, &self->super);
+
+  TIMER_REGISTER_EFFECT(self->timer, self->my_reaction);
+}
+
+ENTRY_POINT(MyReactor, FOREVER, true)
+
+int main(void) {
+  lf_start();
+  return 0;
+}

examples/riot/hello/Makefile

@@ -0,0 +1,18 @@
+# name of your application
+APPLICATION = lf-test
+
+# If no BOARD is found in the environment, use this default:
+BOARD ?= native
+
+# Comment this out to disable code in RIOT that does safety checking
+# which is not needed in a production environment but helps in the
+# development process:
+DEVELHELP ?= 1
+
+# Change this to 0 show compiler invocation lines by default:
+QUIET ?= 1
+
+# Enable reactor-uc features
+# CFLAGS += -DNETWORK_POSIX_TCP
+
+include $(CURDIR)/../../../make/riot/riot.mk

examples/riot/hello/main.c

@@ -0,0 +1,31 @@
+#include "reactor-uc/reactor-uc.h"
+#include <inttypes.h>
+
+DEFINE_TIMER(MyTimer, 1, 0, MSEC(100))
+DEFINE_REACTION(MyReactor, 0, 0)
+
+typedef struct {
+  Reactor super;
+  MyReactor_0 my_reaction;
+  MyTimer timer;
+  Reaction *_reactions[1];
+  Trigger *_triggers[1];
+} MyReactor;
+
+REACTION_BODY(MyReactor, 0, { printf("Hello World @ %lld\n", env->get_elapsed_logical_time(env)); })
+
+void MyReactor_ctor(MyReactor *self, Environment *env) {
+  self->_reactions[0] = (Reaction *)&self->my_reaction;
+  self->_triggers[0] = (Trigger *)&self->timer;
+  Reactor_ctor(&self->super, "MyReactor", env, NULL, NULL, 0, self->_reactions, 1, self->_triggers, 1);
+  MyReactor_0_ctor(&self->my_reaction, &self->super);
+  Timer_ctor(&self->timer.super, &self->super, MSEC(0), MSEC(100), self->timer.effects, 1);
+  TIMER_REGISTER_EFFECT(self->timer, self->my_reaction);
+}
+
+ENTRY_POINT(MyReactor, FOREVER, true)
+
+int main() {
+  lf_start();
+  return 0;
+}

make/riot/external_modules/nanopb/Makefile

@@ -0,0 +1,6 @@
+include $(RIOTBASE)/Makefile.base
+
+SRC_DIR := $(realpath $(CURDIR)/../../../../external/nanopb)
+
+all:
+	$(QQ)"$(MAKE)" -C $(SRC_DIR) -f $(CURDIR)/nanopb.mk

make/riot/external_modules/nanopb/Makefile.include

@@ -0,0 +1,5 @@
+CFLAGS += -DPLATFORM_RIOT=1
+
+# Use an immediate variable to evaluate `MAKEFILE_LIST` now
+USEMODULE_INCLUDES_nanopb := $(LAST_MAKEFILEDIR)/../../../../external
+USEMODULE_INCLUDES += $(USEMODULE_INCLUDES_nanopb)

make/riot/external_modules/nanopb/nanopb.mk

@@ -0,0 +1,3 @@
+MODULE = nanopb
+
+include $(RIOTBASE)/Makefile.base

make/riot/external_modules/proto/Makefile

@@ -0,0 +1,6 @@
+include $(RIOTBASE)/Makefile.base
+
+SRC_DIR := $(realpath $(CURDIR)/../../../../external/proto)
+
+all:
+	$(QQ)"$(MAKE)" -C $(SRC_DIR) -f $(CURDIR)/proto.mk

make/riot/external_modules/proto/Makefile.include

@@ -0,0 +1,5 @@
+CFLAGS += -DPLATFORM_RIOT=1
+
+# Use an immediate variable to evaluate `MAKEFILE_LIST` now
+USEMODULE_INCLUDES_proto := $(LAST_MAKEFILEDIR)/../../../../external
+USEMODULE_INCLUDES += $(USEMODULE_INCLUDES_proto)

make/riot/external_modules/proto/proto.mk

@@ -0,0 +1,3 @@
+MODULE = proto
+
+include $(RIOTBASE)/Makefile.base

make/riot/external_modules/reactor-uc/Makefile

@@ -0,0 +1,6 @@
+include $(RIOTBASE)/Makefile.base
+
+SRC_DIR := $(realpath $(CURDIR)/../../../../src)
+
+all:
+	$(QQ)"$(MAKE)" -C $(SRC_DIR) -f $(CURDIR)/reactor-uc.mk

make/riot/external_modules/reactor-uc/Makefile.dep

@@ -0,0 +1,24 @@
+USEMODULE += ztimer64
+USEMODULE += ztimer64_usec
+USEMODULE += nanopb
+USEMODULE += proto
+
+# If Feature NETWORK_POSIX_TCP is enabled
+ifeq ($(filter -DNETWORK_POSIX_TCP, $(CFLAGS)), -DNETWORK_POSIX_TCP)
+  # Enable networking
+  USEMODULE += netdev_default
+  USEMODULE += auto_init_gnrc_netif
+
+  # Enable sockets
+  USEMODULE += gnrc_ipv6_default
+  USEMODULE += sock_tcp
+  USEMODULE += posix_sockets
+  USEMODULE += posix_sleep
+  USEMODULE += posix_inet
+
+  # Enable posix threads
+  ifneq ($(BOARD),native)
+    USEMODULE += pthread
+  endif
+endif
+

make/riot/external_modules/reactor-uc/Makefile.include

@@ -0,0 +1,15 @@
+
+CFLAGS += -DPLATFORM_RIOT=1
+
+# Remove the -Wcast-align flag for this module
+CFLAGS := $(filter-out -Wcast-align,$(CFLAGS))
+
+# Remove the -Wstrict-prototypes flag for this module
+CFLAGS := $(filter-out -Wstrict-prototypes,$(CFLAGS))
+
+# Remove the -Wold-style-definition flag for this module
+CFLAGS := $(filter-out -Wold-style-definition,$(CFLAGS))
+
+# Use an immediate variable to evaluate `MAKEFILE_LIST` now
+USEMODULE_INCLUDES_reactor-uc := $(LAST_MAKEFILEDIR)/../../../../include
+USEMODULE_INCLUDES += $(USEMODULE_INCLUDES_reactor-uc)

make/riot/external_modules/reactor-uc/reactor-uc.mk

@@ -0,0 +1,3 @@
+MODULE = reactor-uc
+
+include $(RIOTBASE)/Makefile.base

make/riot/riot.mk

@@ -0,0 +1,23 @@
+RIOT_MK_DIR := $(dir $(lastword $(MAKEFILE_LIST)))
+
+# This has to be the absolute path to the RIOT base directory:
+RIOTBASE ?= $(RIOT_MK_DIR)/../../../RIOT
+
+# Comment this out to disable code in RIOT that does safety checking
+# which is not needed in a production environment but helps in the
+# development process:
+DEVELHELP ?= 1
+
+# Change this to 0 show compiler invocation lines by default:
+QUIET ?= 1
+
+# Use a peripheral timer for the delay, if available
+FEATURES_OPTIONAL += periph_timer
+
+# External modules
+EXTERNAL_MODULE_DIRS += $(RIOT_MK_DIR)/external_modules
+USEMODULE += reactor-uc
+
+
+
+include $(RIOTBASE)/Makefile.include

src/platform/posix/tcp_ip_channel.c

@@ -217,10 +217,21 @@ void TcpIpChannel_register_callback(NetworkChannel *untyped_self,
   if (pthread_attr_init(&self->receive_thread_attr) < 0) {
     throw("pthread_attr_init failed");
   }
+/* TODO: RIOT posix-wrappers don't have pthread_attr_setstack yet */
+#ifdef __USE_XOPEN2K
   if (pthread_attr_setstack(&self->receive_thread_attr, &self->receive_thread_stack,
                             TCP_IP_CHANNEL_RECV_THREAD_STACK_SIZE - TCP_IP_CHANNEL_RECV_THREAD_STACK_GUARD_SIZE) < 0) {
     throw("pthread_attr_setstack failed");
   }
+#else
+  if (pthread_attr_setstackaddr(&self->receive_thread_attr, self->receive_thread_stack) != 0) {
+    throw("pthread_attr_setstackaddr failed");
+  }
+  if (pthread_attr_setstacksize(&self->receive_thread_attr, TCP_IP_CHANNEL_RECV_THREAD_STACK_SIZE -
+                                                                TCP_IP_CHANNEL_RECV_THREAD_STACK_GUARD_SIZE) != 0) {
+    throw("pthread_attr_setstacksize failed");
+  }
+#endif
   res = pthread_create(&self->receive_thread, &self->receive_thread_attr, TcpIpChannel_receive_thread, self);
   if (res < 0) {
     throw("pthread_create failed");