`ogma-core`: ROS backend incorrectly maps `float`, `double` type to `std::float32` and `std::float64`

[ivanperez-keera]

*Description**

The ROS backend is, by default, assuming that the data carried by std_msgs::msg::Float32 is of type float32, when it appears to be just a float. The same is happening for Float64, float64 and double. The code currently produced for those cases does not compile.

The type mappings are described in http://docs.ros.org/en/humble/Concepts/Basic/About-Interfaces.html, which states that, in C++, float and double should be used.

Type

• Bug: backend generates incorrect code.

Additional context

None.

Requester

• Alexander Will and Robert Grizzard (VCU)

Method to check presence of bug

Compiling a specification with an input of type Float or Double results in code that will not compile:

--- ROS.hs
import Copilot.Compile.C99
import Copilot.Language
import Language.Copilot    (reify)
import Prelude             hiding (not, (>=))

inputSignal :: Stream Float
inputSignal = extern "input_signal" Nothing

propTestCopilot :: Stream Bool
propTestCopilot = inputSignal >= 5

spec :: Spec
spec = do
  trigger "handlerTestCopilot" (not propTestCopilot) []

main :: IO ()
main = reify spec >>= compileWith settings "monitor"
  where
    settings = mkDefaultCSettings
                 { cSettingsOutputDirectory = "demo/copilot/src/" }

--- vars-db
("input_signal","float","/demo/topic","float")

$ ogma ros --app-target-dir demo --variable-db vars-db --variable-file ogma-cli/examples/ros-copilot/variables --handlers-file ogma-cli/examples/ros-copilot/handlers
$ cabal v1-exec -- runhaskell ROS.hs
$ cd demo/
$ docker build  .
Sending build context to Docker daemon  13.31kB
Step 1/12 : FROM osrf/space-ros:latest
 ---> 3737e04f8b7c
Step 2/12 : ARG USER=spaceros-user
 ---> Running in 000def0bb6b9
Removing intermediate container 000def0bb6b9
 ---> 501fe9476618
Step 3/12 : ARG PACKAGE_PATH=/home/${USER}/monitors
 ---> Running in 6a1ea90b9f15
Removing intermediate container 6a1ea90b9f15
 ---> 9a76021069e9
Step 4/12 : ARG ROS_PATH=/home/${USER}/spaceros/
 ---> Running in a2475046971b
Removing intermediate container a2475046971b
 ---> 9b55d23d5e4c
Step 5/12 : RUN mkdir -p ${PACKAGE_PATH}/src/
 ---> Running in 8450449dcbc9
Removing intermediate container 8450449dcbc9
 ---> ac553c5a0497
Step 6/12 : ADD copilot ${PACKAGE_PATH}/src/copilot
 ---> 79264c5d486b
Step 7/12 : USER root
 ---> Running in fb3120dfb81c
Removing intermediate container fb3120dfb81c
 ---> fc106f45d0aa
Step 8/12 : RUN chown -R ${USER} ${PACKAGE_PATH}
 ---> Running in e8d1c031d73a
Removing intermediate container e8d1c031d73a
 ---> ae8e465b31d5
Step 9/12 : USER ${USER}
 ---> Running in e295eb65f452
Removing intermediate container e295eb65f452
 ---> c1b9ff3b0ca5
Step 10/12 : SHELL ["/bin/bash", "-c"]
 ---> Running in 0d9932c678a2
Removing intermediate container 0d9932c678a2
 ---> 563d710e981f
Step 11/12 : WORKDIR ${PACKAGE_PATH}
 ---> Running in a29cd3f6a93b
Removing intermediate container a29cd3f6a93b
 ---> f15020c12cd9
Step 12/12 : RUN source ${ROS_PATH}/install/setup.bash &&     colcon build
 ---> Running in 1a9a8a98a8a9
Starting >>> copilot
--- stderr: copilot
/home/spaceros-user/monitors/src/copilot/src/copilot_monitor.cpp:25:6: error: ‘float32’ in namespace ‘std’ does not name a type; did you mean ‘float_t’?
   25 | std::float32 input_signal;
      |      ^~~~~~~
      |      float_t
gmake[2]: *** [CMakeFiles/copilot.dir/build.make:76: CMakeFiles/copilot.dir/src/copilot_monitor.cpp.o] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:137: CMakeFiles/copilot.dir/all] Error 2
gmake: *** [Makefile:146: all] Error 2
---
Failed   <<< copilot [16.4s, exited with code 2]

Summary: 0 packages finished [18.4s]
  1 package failed: copilot
  1 package had stderr output: copilot
The command '/bin/bash -c source ${ROS_PATH}/install/setup.bash &&     colcon build' returned a non-zero code: 2

Expected result

The execution above should produce a Copilot specification that can be compiled using docker.

Desired result

The execution above should produce a Copilot specification that can be compiled using docker.

Proposed solution

Modify the ROS backend to map the contents of Float32 messages to float, and variables of type float (in the vars DB) to just float in C++.

Further notes

None.

[ivanperez-keera]

Change Manager: Confirmed that the issue exists.

[ivanperez-keera]

Technical Lead: Confirmed that the issue should be addressed.

[ivanperez-keera]

Technical Lead: Issue scheduled for fixing in Ogma 1.4.

Fix assigned to: @ivanperez-keera.

[ivanperez-keera]

Implementor: Solution implemented, review requested.

[ivanperez-keera]

Change Manager: Verified that:

• Solution is implemented:
  • [X] The code proposed compiles passes the tests. Details:
  • Build logs:
    • https://github.com/nasa/ogma/actions/runs/9186277306/job/25261690504?pr=142
    • https://github.com/nasa/ogma/actions/runs/9186277311/job/25261690495?pr=142
  • Build log archives:
    • logs_24041919067.zip
    • logs_24041919077.zip
  • [X] The solution proposed fixes the issues described. Performed by visual inspection (see CI job [step](https://github.com/nasa/ogma/actions/runs/9186277311/job/25261690495?pr=142#step:8:1 for details) and updated examples used by the same job). The CI job that checks that the ros command generates valid ROS applications now uses an example with a float and a double.
• [X] Implementation is documented. Details: No changes needed.
• [X] Change history is clear.
• [X] Commit messages are clear.
• [X] Changelogs are updated.
• [X] Examples are updated. Details: Example updated with float and double variable.
• [X] Required version bumps are evaluated. Details: Bump not needed (bug fix).

[ivanperez-keera]

Change Manager: Implementation ready to be merged.