17066: sys/irq: Add C++ wrapper using RAII r=maribu a=jenswet
### Contribution description
This adds a C++ wrapper around the `irq.h` API. The wrapper uses RAII to accomplish a convenient and bug resistent use.
A little background: I'm currently writing my master thesis on using C++ for embedded development, at the working group that `@maribu` is part of. For that I will try to add better C++ support to several parts of RIOT and then do some benchmarking and metrics to compare it with the C implementation. For example, I also plan to add a wrapper around i2c, a std::cout drop-in replacement and probably some more about networks or threads.
### Testing procedure
I've added a unit test to verify that the IRQ wrapper calls the original `irq` functions as expected. As C++ and wrapper testing isn't done much so far in this project, I've added two additional headers to ease testing:
1. #17076 - fake functions framework, already merged
2. As there is no framework for C++ unit tests yet, I've added something for this too. Unfortunately the existing frameworks like GoogleTest, CppUTest or CppUnit don't easily compile for embedded or are difficult to integrate in to the RIOT build process. That's why I wrote some (simple) helper functions and macros inspired by the above frameworks. That allows to create C++ tests based on a fixture class with set up and tear down methods. It also allows some simple assertions and is easily extendable for other use cases. It wraps some of the fff functionality too.
Both of this is obviously not required for the initial reason of this PR. But I'd like to provide unit tests for the features that I suggest to introduce where possible. So I'd appreciate some feedback on that too. If you'd prefer a PR without or different tests please let me know.
You can run the test `irq_cpp` locally or on the CI to test the implementation.
Please feel free to give feedback or suggest improvements!
Co-authored-by: Jens Wetterich <jens@wetterich-net.de>
There are a number of tests included in RIOT. They are located in the
tests folder. These tests
allow basic functionality to be verified as well as provide an example of
usage.
Running automated tests
Some tests can be performed automatically. The test automation scripts are
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and interact through the serial (typically UART) with the test application code running on a
board to do the validation. It is recommended to flash the board with the
test just before running it because some platforms cannot be reset while
testing.
Running single test
From the test application directory run:
BOARD=<board_of_your_choice> make flash test
An automated way of knowing if a test is available is to execute the
'test/available' target from the test application directory.
It executes without error if tests run by 'make test' are present.
make test/available
Running all test for particular board
If you would like execute all tests for given board, you could use dedicated
script compile_and_test_for_board.py
Running tests that require a preliminary manual configuration
Some tests need active monitoring or manual setup steps but still have some
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Running tests that require root privileges
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For running them, follow the setup or analysis documentation and use the
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Cleaning intermediate files
After test execution intermediate files are not automatically deleted.
Execution of multiple tests, especially all for particular board could generate
many files. For example, after execution of all test for stm32f469i-disco board
(more than 230 tests) around 7.5 GB of intermediate files are created.
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If you would like to clean intermediate file only for particular board you should
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If you would like to clean intermediate files for all boards go to main RIOT
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@warning This command cleans all local files, for example, pkg downloads and
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make distclean
Implementing automated tests
The goal is to be able to run all tests in a sequential way for as many targets
as possible.
As some board can't be reset without a manual trigger tests should be implemented
with some kind of synchronization. This can be done in two ways:
use test_utils_interactive_sync when uart input/output does not need to be
disabled for the test. This is enabled by default.
set up the test in a loop so the test script will be able so sync with some kind
of start condition in the test.
The module for the first option is test_utils_interactive_sync and is set as a
default module in Makefile.tests_common. It can be disabled by setting in the
application makefile DISABLE_MODULE += test_utils_interactive_sync. The python
test script will adapt to it automatically.
When using the shell module, test_utils_interactive_sync will use the shell
itself to synchronize, and will not use test_utils_interactive_sync(); function
to synchronize. Some times you will want to synchronize before the start of the
script and use test_utils_interactive_sync(); function (e.g.:
tests/ps_schedstatistics). For these cases
you can disable test_utils_interactive_sync_shell module in the application
Makefile: DISABLE_MODULE += test_utils_interactive_sync_shell.
Automated Tests Guidelines
When using pexpect$ is useless for matching the end of a line, instead use
\r\n(pexpect end-of-line).
Beware of + and * at the end of patterns. These patterns will always get
a minimal match (non-greedy).(pexpect end-of-patterns)
This can be an issue when matching groups and using the matched groups to verify
some kind of behavior since * could return an empty match and + only a subset.
This is especially prevalent since printf() is buffered so the output might not
arrive in a single read to pexpect.
To avoid this make sure to match a non-ambiguous character at the end of the
pattern like \r\n, \s, \), etc..
don't:
child.expect(r'some string: (\d+)')
do:
child.expect(r'some string: (\d+)\r\n')
child.expect(r'some string: (\d+)\s')
child.expect(r'some string: (\d+) ,')
Use expect() instead of assert()
In order to make a test application functional in all cases, use expect()
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expect() is defined in the header test_utils/expect.h.
Interaction through the uart
Tests implemented with testrunner use the cleanterm target that
provides an interaction without adding extra text output or input handling.
It can currently be expected to have unmodified line based interaction with the
board.
The expected behavior is verified with the test in tests/test_tools.
Tests cannot rely on having on all boards and terminal programs:
unbuffered input
allowing sending special characters like ctrl+c/ctrl+d
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