Implement rmw_set_log_severity

[rotu]

The existing rmw_set_log_severity currently just throws an error. This implements it.

[dirk-thomas]

@rotu Please run CI builds showing that this patch fixes the test failures #147 was addressing.

[rotu]

This on its own does not fix the test failures #147 was addressing. It may or may not be possible to fix the test using this development, depending on the design of launch_testing.

[dirk-thomas]

Please either come up with a working solution to resolve the test failures or we should reopen the previous PR and merge it as a temporary solution.

[rotu]

@dirk-thomas a working solution is to remove the strict flag in the calls to expect_output. There is no guarantee that this is the only output from Cyclone - and putting human-readable warning messages on stderr is a feature, not a bug.

[dirk-thomas]

a working solution is to remove the strict flag in the calls to expect_output.

These CLI tests checks for strict output for a reason. They not only ensure that certain output is present but also ensure that no other output like warnings / errors / wrong information is present. So no, strict=False is not an appropriate solution.

Please either suggest a viable alternative or we should use the previous proposed PR.

[rotu]

@dirk-thomas This discussion does not belong on this PR. Creating an issue and moving discussion there.

[Karsten1987]

I think this change introduced a warning implicit-fallthrough. Is that on purpose? If so, does it make sense to explicitly disable this warning around that block of code? That would help people like me how compile their workspace with -Werror ;-)

--- stderr: rmw_cyclonedds_cpp
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp: In function ‘rmw_ret_t rmw_set_log_severity(rmw_log_severity_t)’:
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:356:12: error: this statement may fall through [-Werror=implicit-fallthrough=]
       mask |= DDS_LC_DISCOVERY | DDS_LC_THROTTLE | DDS_LC_CONFIG;
            ^
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:357:5: note: here
     case RMW_LOG_SEVERITY_INFO:
     ^~~~
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:358:12: error: this statement may fall through [-Werror=implicit-fallthrough=]
       mask |= DDS_LC_INFO;
            ^
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:359:5: note: here
     case RMW_LOG_SEVERITY_WARN:
     ^~~~
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:360:12: error: this statement may fall through [-Werror=implicit-fallthrough=]
       mask |= DDS_LC_WARNING;
            ^
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:361:5: note: here
     case RMW_LOG_SEVERITY_ERROR:
     ^~~~
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:362:12: error: this statement may fall through [-Werror=implicit-fallthrough=]
       mask |= DDS_LC_ERROR;
            ^
/home/karsten/ros2_ws/src/ros2/rmw_cyclonedds/rmw_cyclonedds_cpp/src/rmw_node.cpp:363:5: note: here
     case RMW_LOG_SEVERITY_FATAL:
     ^~~~
cc1plus: all warnings being treated as errors

[rotu]

@Karsten1987

I think this change introduced a warning implicit-fallthrough. Is that on purpose?

The fallthrough is intentional, and I should fix this warning. What compiler and build flags are you using?

[Karsten1987]

using g++ 7.4.0 on ubuntu 18.04 with -Werror. I don't see that warning with Clang (clang-1001.0.46.4)