Differential D11098 Diff 29355 mercurial/dirstateutils/docket.py

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mercurial/dirstateutils/docket.py

	# dirstatedocket.py - docket file for dirstate-v2			# dirstatedocket.py - docket file for dirstate-v2
	#			#
	# Copyright Mercurial Contributors			# Copyright Mercurial Contributors
	#			#
	# This software may be used and distributed according to the terms of the			# This software may be used and distributed according to the terms of the
	# GNU General Public License version 2 or any later version.			# GNU General Public License version 2 or any later version.

	from __future__ import absolute_import			from __future__ import absolute_import

	import struct			import struct

	from ..revlogutils import docket as docket_mod			from ..revlogutils import docket as docket_mod


	V2_FORMAT_MARKER = b"dirstate-v2\n"			V2_FORMAT_MARKER = b"dirstate-v2\n"

				# Must match the constant of the same name in
				# `rust/hg-core/src/dirstate_tree/on_disk.rs`
				TREE_METADATA_SIZE = 40

	# * 12 bytes: format marker			# * 12 bytes: format marker
	# * 32 bytes: node ID of the working directory's first parent			# * 32 bytes: node ID of the working directory's first parent
	# * 32 bytes: node ID of the working directory's second parent			# * 32 bytes: node ID of the working directory's second parent
	# * 4 bytes: big-endian used size of the data file			# * 4 bytes: big-endian used size of the data file
				# * {TREE_METADATA_SIZE} bytes: tree metadata, parsed separately
	# * 1 byte: length of the data file's UUID			# * 1 byte: length of the data file's UUID
	# * variable: data file's UUID			# * variable: data file's UUID
	#			#
	# Node IDs are null-padded if shorter than 32 bytes.			# Node IDs are null-padded if shorter than 32 bytes.
	# A data file shorter than the specified used size is corrupted (truncated)			# A data file shorter than the specified used size is corrupted (truncated)
	HEADER = struct.Struct(">{}s32s32sLB".format(len(V2_FORMAT_MARKER)))			HEADER = struct.Struct(
				">{}s32s32sL{}sB".format(len(V2_FORMAT_MARKER), TREE_METADATA_SIZE)
				)


	class DirstateDocket(object):			class DirstateDocket(object):
	data_filename_pattern = b'dirstate.%s.d'			data_filename_pattern = b'dirstate.%s.d'

	def __init__(self, parents, data_size, uuid):			def __init__(self, parents, data_size, tree_metadata, uuid):
	self.parents = parents			self.parents = parents
	self.data_size = data_size			self.data_size = data_size
				self.tree_metadata = tree_metadata
	self.uuid = uuid			self.uuid = uuid

	@classmethod			@classmethod
	def with_new_uuid(cls, parents, data):			def with_new_uuid(cls, parents, data_size, tree_metadata):
	return cls(parents, data, docket_mod.make_uid())			return cls(parents, data_size, tree_metadata, docket_mod.make_uid())

	@classmethod			@classmethod
	def parse(cls, data, nodeconstants):			def parse(cls, data, nodeconstants):
	if not data:			if not data:
	parents = (nodeconstants.nullid, nodeconstants.nullid)			parents = (nodeconstants.nullid, nodeconstants.nullid)
	return cls(parents, 0, None)			return cls(parents, 0, b'', None)
	marker, p1, p2, data_size, uuid_size = HEADER.unpack_from(data)			marker, p1, p2, data_size, meta, uuid_size = HEADER.unpack_from(data)
	if marker != V2_FORMAT_MARKER:			if marker != V2_FORMAT_MARKER:
	raise ValueError("expected dirstate-v2 marker")			raise ValueError("expected dirstate-v2 marker")
	uuid = data[HEADER.size : HEADER.size + uuid_size]			uuid = data[HEADER.size : HEADER.size + uuid_size]
	p1 = p1[: nodeconstants.nodelen]			p1 = p1[: nodeconstants.nodelen]
	p2 = p2[: nodeconstants.nodelen]			p2 = p2[: nodeconstants.nodelen]
	return cls((p1, p2), data_size, uuid)			return cls((p1, p2), data_size, meta, uuid)

	def serialize(self):			def serialize(self):
	p1, p2 = self.parents			p1, p2 = self.parents
	header = HEADER.pack(			header = HEADER.pack(
	V2_FORMAT_MARKER, p1, p2, self.data_size, len(self.uuid)			V2_FORMAT_MARKER,
				p1,
				p2,
				self.data_size,
				self.tree_metadata,
				len(self.uuid),
	)			)
	return header + self.uuid			return header + self.uuid

	def data_filename(self):			def data_filename(self):
	return self.data_filename_pattern % self.uuid			return self.data_filename_pattern % self.uuid