Mercurial > hg
view mercurial/revlogutils/concurrency_checker.py @ 51725:bbe59cc5d2e1
rust-changelog: accessing the index
The `Index` object is currently the one providing all DAG related
algorithms, starting with simple ancestors iteration up to more
advanced ones (ranges, common ancestors…).
From pure Rust code, there was no way to access the changelog index for
a given `Repository`, probably because `rhg` does not use any such algorithm
yet.
author | Georges Racinet <georges.racinet@cloudcrane.io> |
---|---|
date | Mon, 22 Jul 2024 18:20:29 +0200 |
parents | e9901d01d135 |
children | 1c5810ce737e |
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from ..i18n import _ from .. import error def get_checker(ui, revlog_name=b'changelog'): """Get a function that checks file handle position is as expected. This is used to ensure that files haven't been modified outside of our knowledge (such as on a networked filesystem, if `hg debuglocks` was used, or writes to .hg that ignored locks happened). Due to revlogs supporting a concept of buffered, delayed, or diverted writes, we're allowing the files to be shorter than expected (the data may not have been written yet), but they can't be longer. Please note that this check is not perfect; it can't detect all cases (there may be false-negatives/false-OKs), but it should never claim there's an issue when there isn't (false-positives/false-failures). """ vpos = ui.config(b'debug', b'revlog.verifyposition.' + revlog_name) # Avoid any `fh.tell` cost if this isn't enabled. if not vpos or vpos not in [b'log', b'warn', b'fail']: return None def _checker(fh, fn, expected): if fh.tell() <= expected: return msg = _(b'%s: file cursor at position %d, expected %d') # Always log if we're going to warn or fail. ui.log(b'debug', msg + b'\n', fn, fh.tell(), expected) if vpos == b'warn': ui.warn((msg + b'\n') % (fn, fh.tell(), expected)) elif vpos == b'fail': raise error.RevlogError(msg % (fn, fh.tell(), expected)) return _checker