5b2d8661c9
703b1e612a4bd4521e20ae21eb8fb7c19f4ef942 Close minor startup race between main and scheduler threads (Larry Ruane)
Pull request description:
This is a low-priority bug fix. The scheduler thread runs `CheckForStaleTipAndEvictPeers()` every 45 seconds (EXTRA_PEER_CHECK_INTERVAL). If its first run happens before the active chain is set up (`CChain::SetTip()`), `bitcoind` will assert:
```
(...)
2021-07-28T22:16:49Z init message: Loading block index…
bitcoind: validation.cpp:4968: CChainState& ChainstateManager::ActiveChainstate() const: Assertion `m_active_chainstate' failed.
Aborted (core dumped)
```
I ran into this while using the debugger to investigate an unrelated problem. Single-stepping through threads with a debugger can cause the relative thread execution timing to be very different than usual. I don't think any automated tests are needed for this PR. I'll give reproduction steps in the next PR comment.
ACKs for top commit:
MarcoFalke:
cr ACK 703b1e612a4bd4521e20ae21eb8fb7c19f4ef942
tryphe:
tested ACK 703b1e612a4bd4521e20ae21eb8fb7c19f4ef942
0xB10C:
ACK 703b1e612a4bd4521e20ae21eb8fb7c19f4ef942
glozow:
code review ACK 703b1e612a4bd4521e20ae21eb8fb7c19f4ef942 - it makes sense to me to start peerman's background tasks here, after `chainstate->LoadChainTip()` and `node.connman->Start()` have been called.
Tree-SHA512: 9316ad768cba3b171f62e2eb400e3790af66c47d1886d7965edb38d9710fc8c8f8e4fb38232811c9346732ce311d39f740c5c2aaf5f6ca390ddc48c51a8d633b
Unit tests
The sources in this directory are unit test cases. Boost includes a unit testing framework, and since Bitcoin Core already uses Boost, it makes sense to simply use this framework rather than require developers to configure some other framework (we want as few impediments to creating unit tests as possible).
The build system is set up to compile an executable called test_bitcoin
that runs all of the unit tests. The main source file for the test library is found in
util/setup_common.cpp.
Compiling/running unit tests
Unit tests will be automatically compiled if dependencies were met in ./configure
and tests weren't explicitly disabled.
After configuring, they can be run with make check.
To run the unit tests manually, launch src/test/test_bitcoin. To recompile
after a test file was modified, run make and then run the test again. If you
modify a non-test file, use make -C src/test to recompile only what's needed
to run the unit tests.
To add more unit tests, add BOOST_AUTO_TEST_CASE functions to the existing
.cpp files in the test/ directory or add new .cpp files that
implement new BOOST_AUTO_TEST_SUITE sections.
To run the GUI unit tests manually, launch src/qt/test/test_bitcoin-qt
To add more GUI unit tests, add them to the src/qt/test/ directory and
the src/qt/test/test_main.cpp file.
Running individual tests
test_bitcoin has some built-in command-line arguments; for
example, to run just the getarg_tests verbosely:
test_bitcoin --log_level=all --run_test=getarg_tests -- DEBUG_LOG_OUT
log_level controls the verbosity of the test framework, which logs when a
test case is entered, for example. The DEBUG_LOG_OUT after the two dashes
redirects the debug log, which would normally go to a file in the test datadir
(BasicTestingSetup::m_path_root), to the standard terminal output.
... or to run just the doubledash test:
test_bitcoin --run_test=getarg_tests/doubledash
Run test_bitcoin --help for the full list.
Adding test cases
To add a new unit test file to our test suite you need
to add the file to src/Makefile.test.include. The pattern is to create
one test file for each class or source file for which you want to create
unit tests. The file naming convention is <source_filename>_tests.cpp
and such files should wrap their tests in a test suite
called <source_filename>_tests. For an example of this pattern,
see uint256_tests.cpp.
Logging and debugging in unit tests
make check will write to a log file foo_tests.cpp.log and display this file
on failure. For running individual tests verbosely, refer to the section
above.
To write to logs from unit tests you need to use specific message methods
provided by Boost. The simplest is BOOST_TEST_MESSAGE.
For debugging you can launch the test_bitcoin executable with gdbor lldb and
start debugging, just like you would with any other program:
gdb src/test/test_bitcoin