Mercurial > public > mercurial-scm > hg-stable
diff mercurial/dirstatemap.py @ 49695:a3b1ab5f5dee stable
dirstate: deal with read-race for pure python code
If we cannot read the dirstate data, this is probably because a writing process
wrote it under our feet. So refresh the docket and try again a handful of time.
| author | Pierre-Yves David <pierre-yves.david@octobus.net> |
|---|---|
| date | Tue, 28 Feb 2023 19:01:20 +0100 |
| parents | 53f196622699 |
| children | c9066fc609ef |
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--- a/mercurial/dirstatemap.py Wed Mar 01 16:05:28 2023 +0100 +++ b/mercurial/dirstatemap.py Tue Feb 28 19:01:20 2023 +0100 @@ -37,6 +37,9 @@ WRITE_MODE_FORCE_APPEND = 2 +V2_MAX_READ_ATTEMPTS = 5 + + class _dirstatemapcommon: """ Methods that are identical for both implementations of the dirstatemap @@ -125,6 +128,21 @@ return self._docket def _read_v2_data(self): + data = None + attempts = 0 + while attempts < V2_MAX_READ_ATTEMPTS: + attempts += 1 + try: + data = self._opener.read(self.docket.data_filename()) + except FileNotFoundError: + # read race detected between docket and data file + # reload the docket and retry + self._docket = None + if data is None: + assert attempts >= V2_MAX_READ_ATTEMPTS + msg = b"dirstate read race happened %d times in a row" + msg %= attempts + raise error.Abort(msg) return self._opener.read(self.docket.data_filename()) def write_v2_no_append(self, tr, st, meta, packed):