[bburda]

Pull Request

Summary

A SIGINT or SIGTERM that arrives while the gateway is still starting ends it with exit code 0, through the same teardown as a shutdown after startup.

• main blocks SIGINT and SIGTERM before rclcpp::init (with SignalHandlerOptions::None) and keeps them blocked until startup is done. It then installs rclcpp's handlers and unblocks, so a signal sent meanwhile is delivered at that point, the context shuts down, spin returns at once and the explicit teardown runs.
• A shutdown inside the startup used to end in exit code 1 (the next rcl call threw on the shut-down context), or in an abort: rclcpp's NodeGraph::get_graph_event clears its listener flag before add_node throws, and the node's destructor then throws NodeNotFoundError.
• After startup, signals are handled by rclcpp exactly as before.
• Threads that start during startup keep the blocked mask, and exec keeps it too. DefaultScriptProvider resets the mask in the forked child, so stop ends a script with SIGTERM.
• The OPC-UA startup sweep runs during construction. Its cancel check also reads a pending SIGINT or SIGTERM with sigpending(), so a stop still ends the sweep, and the gateway exits once startup is done.

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Issue

• closes [BUG] gateway_node exits 1 or aborts on SIGINT during startup #731

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Type

• Bug fix
• New feature or tests
• Breaking change
• Documentation only

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Testing

• ./scripts/test.sh integ --packages-select ros2_medkit_integration_tests runs test_gateway_startup_signal. It starts the real gateway_node repeatedly, signals it 0 to 10 ms after each of five startup log lines and once it is spinning, and expects exit code 0 every time.
• test_scripts_api checks that stop ends the script process.
• ./scripts/test.sh integ --packages-select ros2_medkit_opcua runs test_opcua_startup_sweep_signal, which sends each signal during a startup sweep against a silent listener on port 4840.

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Checklist

• Breaking changes are clearly described (and announced in docs / changelog if needed)
• Tests were added or updated if needed
• Docs were updated if behavior or public API changed