Handle SIGINT properly in the controller manager

[saikishor]

resolves #2012
resolves #1168
resolves #472

Needed by ros-controls/ros2_control_demos#548

With example_1 of ros2_control_demos:

[ros2_control_node-1] [INFO] [1737720810.651704682] [controller_manager]: Shutdown request received....
[ros2_control_node-1] [INFO] [1737720810.651778082] [controller_manager]: Shutting down all controllers in the controller manager.
[ros2_control_node-1] [INFO] [1737720810.651830233] [controller_manager]: Deactivating controller 'joint_state_broadcaster'
[ros2_control_node-1] [INFO] [1737720810.652020354] [controller_manager]: Shutting down controller 'joint_state_broadcaster'
[ros2_control_node-1] [INFO] [1737720810.652065784] [controller_manager]: Deactivating controller 'forward_position_controller'
[ros2_control_node-1] [INFO] [1737720810.652169914] [controller_manager]: Shutting down controller 'forward_position_controller'
[ros2_control_node-1] [INFO] [1737720810.652240505] [resource_manager]: 'deactivate' hardware 'RRBot' 
[ros2_control_node-1] [INFO] [1737720810.652259975] [controller_manager.resource_manager.hardware_component.system.RRBot]: Deactivating ...please wait...
[INFO] [robot_state_publisher-2]: process has finished cleanly [pid 399725]
[INFO] [rviz2-5]: process has finished cleanly [pid 399819]
[ros2_control_node-1] [INFO] [1737720811.652349811] [controller_manager.resource_manager.hardware_component.system.RRBot]: 3.0 seconds left...
[ros2_control_node-1] [INFO] [1737720812.652490121] [controller_manager.resource_manager.hardware_component.system.RRBot]: 2.0 seconds left...
[ros2_control_node-1] [INFO] [1737720813.652626335] [controller_manager.resource_manager.hardware_component.system.RRBot]: 1.0 seconds left...
[ros2_control_node-1] [INFO] [1737720813.652682125] [controller_manager.resource_manager.hardware_component.system.RRBot]: Successfully deactivated!
[ros2_control_node-1] [INFO] [1737720813.652700605] [resource_manager]: Successful 'deactivate' of hardware 'RRBot'
[ros2_control_node-1] [INFO] [1737720813.652715105] [resource_manager]: 'shutdown' hardware 'RRBot' 
[ros2_control_node-1] [INFO] [1737720813.652722355] [resource_manager]: Successful 'shutdown' of hardware 'RRBot'
[ros2_control_node-1] [INFO] [1737720813.652773225] [controller_manager]: Shutting down the controller manager.

[codecov]

Codecov Report

Attention: Patch coverage is 75.67568% with 9 lines in your changes missing coverage. Please review.

Project coverage is 89.38%. Comparing base (fbfc01d) to head (75f194c).

Files with missing lines	Patch %	Lines
controller_manager/src/controller_manager.cpp	75.86%	2 Missing and 5 partials ⚠️
hardware_interface/src/resource_manager.cpp	75.00%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2014      +/-   ##
==========================================
+ Coverage   89.37%   89.38%   +0.01%     
==========================================
  Files         132      132              
  Lines       14649    14683      +34     
  Branches     1261     1269       +8     
==========================================
+ Hits        13092    13124      +32     
+ Misses       1091     1086       -5     
- Partials      466      473       +7     

Flag	Coverage Δ
unittests	89.38% <75.67%> (+0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
.../include/controller_manager/controller_manager.hpp	100.00% <ø> (ø)
hardware_interface/src/resource_manager.cpp	75.12% <75.00%> (+0.09%)	⬆️
controller_manager/src/controller_manager.cpp	76.20% <75.86%> (-0.08%)	⬇️

... and 3 files with indirect coverage changes

[mjforan]

Tested with
Ubuntu 24.04/Jazzy in Docker

• x86 (ros2_control_demos example_2)
• arm64 (real robot, pca9685_hardware_interface + rm_motors_ros).

Not comprehensive testing, but the issue was fixed and I didn't notice any side effects 👍

[saikishor]

@mjforan
Thank you for testing it out. I'm glad it worked for you :)