Mercurial > hg
view mercurial/revlogutils/sidedata.py @ 45537:2f8227a12592
rhg: add `--revision` argument to `rhg files`
Add the option to list the tracked files of a revision given its number
or full node id.
Benched on a clone of moz-central
where tip is 1671467:81deaa1a68ebb28db0490954034ab38ab269409d
files -r 81deaa1a68ebb28db0490954034ab38ab269409d > out.txt
hg 0m1.633s
rhg 0m0.157s
files -r 81deaa1a68ebb28db0490954034ab38ab269409d > /dev/null
hg 0m0.415s
rhg 0m0.143s
Differential Revision: https://phab.mercurial-scm.org/D9015
author | Antoine Cezar <antoine.cezar@octobus.net> |
---|---|
date | Wed, 09 Sep 2020 14:53:15 +0200 |
parents | a61287a95dc3 |
children | 9a6b409b8ebc |
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# sidedata.py - Logic around store extra data alongside revlog revisions # # Copyright 2019 Pierre-Yves David <pierre-yves.david@octobus.net) # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. """core code for "sidedata" support The "sidedata" are stored alongside the revision without actually being part of its content and not affecting its hash. It's main use cases is to cache important information related to a changesets. The current implementation is experimental and subject to changes. Do not rely on it in production. Sidedata are stored in the revlog itself, withing the revision rawtext. They are inserted, removed from it using the flagprocessors mechanism. The following format is currently used:: initial header: <number of sidedata; 2 bytes> sidedata (repeated N times): <sidedata-key; 2 bytes> <sidedata-entry-length: 4 bytes> <sidedata-content-sha1-digest: 20 bytes> <sidedata-content; X bytes> normal raw text: <all bytes remaining in the rawtext> This is a simple and effective format. It should be enought to experiment with the concept. """ from __future__ import absolute_import import struct from .. import error from ..utils import hashutil ## sidedata type constant # reserve a block for testing purposes. SD_TEST1 = 1 SD_TEST2 = 2 SD_TEST3 = 3 SD_TEST4 = 4 SD_TEST5 = 5 SD_TEST6 = 6 SD_TEST7 = 7 # key to store copies related information SD_P1COPIES = 8 SD_P2COPIES = 9 SD_FILESADDED = 10 SD_FILESREMOVED = 11 # internal format constant SIDEDATA_HEADER = struct.Struct('>H') SIDEDATA_ENTRY = struct.Struct('>HL20s') def sidedatawriteprocessor(rl, text, sidedata): sidedata = list(sidedata.items()) sidedata.sort() rawtext = [SIDEDATA_HEADER.pack(len(sidedata))] for key, value in sidedata: digest = hashutil.sha1(value).digest() rawtext.append(SIDEDATA_ENTRY.pack(key, len(value), digest)) for key, value in sidedata: rawtext.append(value) rawtext.append(bytes(text)) return b''.join(rawtext), False def sidedatareadprocessor(rl, text): sidedata = {} offset = 0 (nbentry,) = SIDEDATA_HEADER.unpack(text[: SIDEDATA_HEADER.size]) offset += SIDEDATA_HEADER.size dataoffset = SIDEDATA_HEADER.size + (SIDEDATA_ENTRY.size * nbentry) for i in range(nbentry): nextoffset = offset + SIDEDATA_ENTRY.size key, size, storeddigest = SIDEDATA_ENTRY.unpack(text[offset:nextoffset]) offset = nextoffset # read the data associated with that entry nextdataoffset = dataoffset + size entrytext = text[dataoffset:nextdataoffset] readdigest = hashutil.sha1(entrytext).digest() if storeddigest != readdigest: raise error.SidedataHashError(key, storeddigest, readdigest) sidedata[key] = entrytext dataoffset = nextdataoffset text = text[dataoffset:] return text, True, sidedata def sidedatarawprocessor(rl, text): # side data modifies rawtext and prevent rawtext hash validation return False processors = ( sidedatareadprocessor, sidedatawriteprocessor, sidedatarawprocessor, )