constants.py
169 lines
| 4.6 KiB
| text/x-python
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PythonLexer
r48023 | # revlogdeltas.py - constant used for revlog logic. | |||
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r39365 | # | ||
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r47575 | # Copyright 2005-2007 Olivia Mackall <olivia@selenic.com> | ||
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r39365 | # Copyright 2018 Octobus <contact@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. | ||||
"""Helper class to compute deltas stored inside revlogs""" | ||||
from __future__ import absolute_import | ||||
r47615 | import struct | |||
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r43346 | from ..interfaces import repository | ||
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r39365 | |||
r47838 | ### Internal utily constants | |||
KIND_CHANGELOG = 1001 # over 256 to not be comparable with a bytes | ||||
KIND_MANIFESTLOG = 1002 | ||||
KIND_FILELOG = 1003 | ||||
KIND_OTHER = 1004 | ||||
ALL_KINDS = { | ||||
KIND_CHANGELOG, | ||||
KIND_MANIFESTLOG, | ||||
KIND_FILELOG, | ||||
KIND_OTHER, | ||||
} | ||||
r47614 | ### main revlog header | |||
r47618 | INDEX_HEADER = struct.Struct(b">I") | |||
r47614 | ## revlog version | |||
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r39365 | REVLOGV0 = 0 | ||
REVLOGV1 = 1 | ||||
# Dummy value until file format is finalized. | ||||
REVLOGV2 = 0xDEAD | ||||
r47614 | ||||
## global revlog header flags | ||||
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r41238 | # Shared across v1 and v2. | ||
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r43346 | FLAG_INLINE_DATA = 1 << 16 | ||
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r41238 | # Only used by v1, implied by v2. | ||
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r43346 | FLAG_GENERALDELTA = 1 << 17 | ||
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r39365 | REVLOG_DEFAULT_FLAGS = FLAG_INLINE_DATA | ||
REVLOG_DEFAULT_FORMAT = REVLOGV1 | ||||
REVLOG_DEFAULT_VERSION = REVLOG_DEFAULT_FORMAT | REVLOG_DEFAULT_FLAGS | ||||
r48004 | REVLOGV0_FLAGS = 0 | |||
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r39365 | REVLOGV1_FLAGS = FLAG_INLINE_DATA | FLAG_GENERALDELTA | ||
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r41238 | REVLOGV2_FLAGS = FLAG_INLINE_DATA | ||
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r39365 | |||
r47614 | ### individual entry | |||
r47615 | ## index v0: | |||
# 4 bytes: offset | ||||
# 4 bytes: compressed length | ||||
# 4 bytes: base rev | ||||
# 4 bytes: link rev | ||||
# 20 bytes: parent 1 nodeid | ||||
# 20 bytes: parent 2 nodeid | ||||
# 20 bytes: nodeid | ||||
INDEX_ENTRY_V0 = struct.Struct(b">4l20s20s20s") | ||||
r47616 | ## index v1 | |||
# 6 bytes: offset | ||||
# 2 bytes: flags | ||||
# 4 bytes: compressed length | ||||
# 4 bytes: uncompressed length | ||||
# 4 bytes: base rev | ||||
# 4 bytes: link rev | ||||
# 4 bytes: parent 1 rev | ||||
# 4 bytes: parent 2 rev | ||||
# 32 bytes: nodeid | ||||
INDEX_ENTRY_V1 = struct.Struct(b">Qiiiiii20s12x") | ||||
assert INDEX_ENTRY_V1.size == 32 * 2 | ||||
r47617 | # 6 bytes: offset | |||
# 2 bytes: flags | ||||
# 4 bytes: compressed length | ||||
# 4 bytes: uncompressed length | ||||
# 4 bytes: base rev | ||||
# 4 bytes: link rev | ||||
# 4 bytes: parent 1 rev | ||||
# 4 bytes: parent 2 rev | ||||
# 32 bytes: nodeid | ||||
# 8 bytes: sidedata offset | ||||
# 4 bytes: sidedata compressed length | ||||
r48025 | # 1 bytes: compression mode (2 lower bit are data_compression_mode) | |||
# 19 bytes: Padding to align to 96 bytes (see RevlogV2Plan wiki page) | ||||
INDEX_ENTRY_V2 = struct.Struct(b">Qiiiiii20s12xQiB19x") | ||||
assert INDEX_ENTRY_V2.size == 32 * 3, INDEX_ENTRY_V2.size | ||||
r47617 | ||||
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r39365 | # revlog index flags | ||
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r40083 | |||
# For historical reasons, revlog's internal flags were exposed via the | ||||
# wire protocol and are even exposed in parts of the storage APIs. | ||||
# revision has censor metadata, must be verified | ||||
REVIDX_ISCENSORED = repository.REVISION_FLAG_CENSORED | ||||
# revision hash does not match data (narrowhg) | ||||
REVIDX_ELLIPSIS = repository.REVISION_FLAG_ELLIPSIS | ||||
# revision data is stored externally | ||||
REVIDX_EXTSTORED = repository.REVISION_FLAG_EXTSTORED | ||||
r46263 | # revision changes files in a way that could affect copy tracing. | |||
REVIDX_HASCOPIESINFO = repository.REVISION_FLAG_HASCOPIESINFO | ||||
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r39365 | REVIDX_DEFAULT_FLAGS = 0 | ||
# stable order in which flags need to be processed and their processors applied | ||||
REVIDX_FLAGS_ORDER = [ | ||||
REVIDX_ISCENSORED, | ||||
REVIDX_ELLIPSIS, | ||||
REVIDX_EXTSTORED, | ||||
r46263 | REVIDX_HASCOPIESINFO, | |||
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r39365 | ] | ||
r42956 | ||||
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r39365 | # bitmark for flags that could cause rawdata content change | ||
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r47843 | REVIDX_RAWTEXT_CHANGING_FLAGS = REVIDX_ISCENSORED | REVIDX_EXTSTORED | ||
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r39542 | |||
r48023 | ## chunk compression mode constants: | |||
# These constants are used in revlog version >=2 to denote the compression used | ||||
# for a chunk. | ||||
r48027 | # Chunk use no compression, the data stored on disk can be directly use as | |||
# chunk value. Without any header information prefixed. | ||||
COMP_MODE_PLAIN = 0 | ||||
r48023 | # Chunk use a compression mode stored "inline" at the start of the chunk | |||
# itself. This is the mode always used for revlog version "0" and "1" | ||||
COMP_MODE_INLINE = 2 | ||||
r48004 | SUPPORTED_FLAGS = { | |||
REVLOGV0: REVLOGV0_FLAGS, | ||||
REVLOGV1: REVLOGV1_FLAGS, | ||||
REVLOGV2: REVLOGV2_FLAGS, | ||||
} | ||||
r48005 | _no = lambda flags: False | |||
_yes = lambda flags: True | ||||
def _from_flag(flag): | ||||
return lambda flags: bool(flags & flag) | ||||
FEATURES_BY_VERSION = { | ||||
REVLOGV0: { | ||||
b'inline': _no, | ||||
b'generaldelta': _no, | ||||
b'sidedata': False, | ||||
r48008 | b'docket': False, | |||
r48005 | }, | |||
REVLOGV1: { | ||||
b'inline': _from_flag(FLAG_INLINE_DATA), | ||||
b'generaldelta': _from_flag(FLAG_GENERALDELTA), | ||||
b'sidedata': False, | ||||
r48008 | b'docket': False, | |||
r48005 | }, | |||
REVLOGV2: { | ||||
r48008 | # The point of inline-revlog is to reduce the number of files used in | |||
# the store. Using a docket defeat this purpose. So we needs other | ||||
# means to reduce the number of files for revlogv2. | ||||
r48005 | b'inline': _no, | |||
b'generaldelta': _yes, | ||||
b'sidedata': True, | ||||
r48008 | b'docket': True, | |||
r48005 | }, | |||
} | ||||
r48023 | ||||
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r39542 | SPARSE_REVLOG_MAX_CHAIN_LENGTH = 1000 | ||