cc62716920
to allocate our limited outbound slots correctly, and to ensure addnode connections benefit from their intended protections. Our addnode logic usually connects the addnode peers before the automatic outbound logic does, but not always, as a connection race can occur. If an addnode peer disconnects us and if it was the only one from its network, there can be a race between reconnecting to it with the addnode thread, and it being picked as automatic network-specific outbound peer. Or our internet connection or router, or the addnode peer, could be temporarily offline, and then return online during the automatic outbound thread. Or we could add a new manual peer using the addnode RPC at that time. The race can be more apparent when our node doesn't know many peers, or with networks like cjdns that currently have few bitcoin peers. When an addnode peer is connected as an automatic outbound peer and is the only connection we have to a network, it can be protected by our new outbound eviction logic and persist in the "wrong role". Examples on mainnet using logging added in the same pull request: 2023-08-12T14:51:05.681743Z [opencon] [net.cpp:1949] [ThreadOpenConnections] [net:debug] Not making automatic network-specific outbound-full-relay connection to i2p peer selected for manual (addnode) connection: [geh...odq.b32.i2p]:0 2023-08-13T03:59:28.050853Z [opencon] [net.cpp:1949] [ThreadOpenConnections] [net:debug] Not making automatic block-relay-only connection to onion peer selected for manual (addnode) connection: kpg...aid.onion:8333 2023-08-13T16:21:26.979052Z [opencon] [net.cpp:1949] [ThreadOpenConnections] [net:debug] Not making automatic network-specific outbound-full-relay connection to cjdns peer selected for manual (addnode) connection: [fcc...8ce]:8333 2023-08-14T20:43:53.401271Z [opencon] [net.cpp:1949] [ThreadOpenConnections] [net:debug] Not making automatic network-specific outbound-full-relay connection to cjdns peer selected for manual (addnode) connection: [fc7...59e]:8333 2023-08-15T00:10:01.894147Z [opencon] [net.cpp:1949] [ThreadOpenConnections] [net:debug] Not making automatic feeler connection to i2p peer selected for manual (addnode) connection: geh...odq.b32.i2p:8333 Finally, there does not seem to be a reason to make block-relay or short-lived feeler connections to addnode peers, as the addnode logic will ensure we connect to them if they are up, within the addnode connection limit. Fix these issues by checking if the address is an addnode peer in our automatic outbound connection logic.
Bitcoin Core integration/staging tree
For an immediately usable, binary version of the Bitcoin Core software, see https://bitcoincore.org/en/download/.
What is Bitcoin Core?
Bitcoin Core connects to the Bitcoin peer-to-peer network to download and fully validate blocks and transactions. It also includes a wallet and graphical user interface, which can be optionally built.
Further information about Bitcoin Core is available in the doc folder.
License
Bitcoin Core is released under the terms of the MIT license. See COPYING for more information or see https://opensource.org/licenses/MIT.
Development Process
The master branch is regularly built (see doc/build-*.md for instructions) and tested, but it is not guaranteed to be
completely stable. Tags are created
regularly from release branches to indicate new official, stable release versions of Bitcoin Core.
The https://github.com/bitcoin-core/gui repository is used exclusively for the development of the GUI. Its master branch is identical in all monotree repositories. Release branches and tags do not exist, so please do not fork that repository unless it is for development reasons.
The contribution workflow is described in CONTRIBUTING.md and useful hints for developers can be found in doc/developer-notes.md.
Testing
Testing and code review is the bottleneck for development; we get more pull requests than we can review and test on short notice. Please be patient and help out by testing other people's pull requests, and remember this is a security-critical project where any mistake might cost people lots of money.
Automated Testing
Developers are strongly encouraged to write unit tests for new code, and to
submit new unit tests for old code. Unit tests can be compiled and run
(assuming they weren't disabled in configure) with: make check. Further details on running
and extending unit tests can be found in /src/test/README.md.
There are also regression and integration tests, written
in Python.
These tests can be run (if the test dependencies are installed) with: test/functional/test_runner.py
The CI (Continuous Integration) systems make sure that every pull request is built for Windows, Linux, and macOS, and that unit/sanity tests are run automatically.
Manual Quality Assurance (QA) Testing
Changes should be tested by somebody other than the developer who wrote the code. This is especially important for large or high-risk changes. It is useful to add a test plan to the pull request description if testing the changes is not straightforward.
Translations
Changes to translations as well as new translations can be submitted to Bitcoin Core's Transifex page.
Translations are periodically pulled from Transifex and merged into the git repository. See the translation process for details on how this works.
Important: We do not accept translation changes as GitHub pull requests because the next pull from Transifex would automatically overwrite them again.