upstream/mercurial-mirror Files · mercurial/pure/base85.py

debugcommands: stub for debugupgraderepo command...

debugcommands: stub for debugupgraderepo command Currently, if Mercurial introduces a new repository/store feature or changes behavior of an existing feature, users must perform an `hg clone` to create a new repository with hopefully the correct/optimal settings. Unfortunately, even `hg clone` may not give the correct results. For example, if you do a local `hg clone`, you may get hardlinks to revlog files that inherit the old state. If you `hg clone` from a remote or `hg clone --pull`, changegroup application may bypass some optimization, such as converting to generaldelta. Optimizing a repository is harder than it seems and requires more than a simple `hg` command invocation. This commit starts the process of changing that. We introduce `hg debugupgraderepo`, a command that performs an in-place upgrade of a repository to use new, optimal features. The command is just a stub right now. Features will be added in subsequent commits. This commit does foreshadow some of the behavior of the new command, notably that it doesn't do anything by default and that it takes arguments that influence what actions it performs. These will be explained more in subsequent commits.

Gregory Szorc - - Load All Authors

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             base85.py
        
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      # base85.py: pure python base85 codec

      #

      # Copyright (C) 2009 Brendan Cully <brendan@kublai.com>

      #

      # This software may be used and distributed according to the terms of the

      # GNU General Public License version 2 or any later version.

      from __future__ import absolute_import

      import struct

      _b85chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" \

                  "abcdefghijklmnopqrstuvwxyz!#$%&()*+-;<=>?@^_`{|}~"

      _b85chars2 = [(a + b) for a in _b85chars for b in _b85chars]

      _b85dec = {}

      def _mkb85dec():

          for i, c in enumerate(_b85chars):

              _b85dec[c] = i

      def b85encode(text, pad=False):

          """encode text in base85 format"""

          l = len(text)

          r = l % 4

          if r:

              text += '\0' * (4 - r)

          longs = len(text) >> 2

          words = struct.unpack('>%dL' % (longs), text)

          out = ''.join(_b85chars[(word // 52200625) % 85] +

                        _b85chars2[(word // 7225) % 7225] +

                        _b85chars2[word % 7225]

                        for word in words)

          if pad:

              return out

          # Trim padding

          olen = l % 4

          if olen:

              olen += 1

          olen += l // 4 * 5

          return out[:olen]

      def b85decode(text):

          """decode base85-encoded text"""

          if not _b85dec:

              _mkb85dec()

          l = len(text)

          out = []

          for i in range(0, len(text), 5):

              chunk = text[i:i + 5]

              acc = 0

              for j, c in enumerate(chunk):

                  try:

                      acc = acc * 85 + _b85dec[c]

                  except KeyError:

                      raise ValueError('bad base85 character at position %d'

                                       % (i + j))

              if acc > 4294967295:

                  raise ValueError('Base85 overflow in hunk starting at byte %d' % i)

              out.append(acc)

          # Pad final chunk if necessary

          cl = l % 5

          if cl:

              acc *= 85 ** (5 - cl)

              if cl > 1:

                  acc += 0xffffff >> (cl - 2) * 8

              out[-1] = acc

          out = struct.pack('>%dL' % (len(out)), *out)

          if cl:

              out = out[:-(5 - cl)]

          return out

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				# base85.py: pure python base85 codec
				#
				# Copyright (C) 2009 Brendan Cully <brendan@kublai.com>
				#
				# This software may be used and distributed according to the terms of the
				# GNU General Public License version 2 or any later version.

				from __future__ import absolute_import

				import struct

				_b85chars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ" \
				"abcdefghijklmnopqrstuvwxyz!#$%&()*+-;<=>?@^_`{\|}~"
				_b85chars2 = [(a + b) for a in _b85chars for b in _b85chars]
				_b85dec = {}

				def _mkb85dec():
				for i, c in enumerate(_b85chars):
				_b85dec[c] = i

				def b85encode(text, pad=False):
				"""encode text in base85 format"""
				l = len(text)
				r = l % 4
				if r:
				text += '\0' * (4 - r)
				longs = len(text) >> 2
				words = struct.unpack('>%dL' % (longs), text)

				out = ''.join(_b85chars[(word // 52200625) % 85] +
				_b85chars2[(word // 7225) % 7225] +
				_b85chars2[word % 7225]
				for word in words)

				if pad:
				return out

				# Trim padding
				olen = l % 4
				if olen:
				olen += 1
				olen += l // 4 * 5
				return out[:olen]

				def b85decode(text):
				"""decode base85-encoded text"""
				if not _b85dec:
				_mkb85dec()

				l = len(text)
				out = []
				for i in range(0, len(text), 5):
				chunk = text[i:i + 5]
				acc = 0
				for j, c in enumerate(chunk):
				try:
				acc = acc * 85 + _b85dec[c]
				except KeyError:
				raise ValueError('bad base85 character at position %d'
				% (i + j))
				if acc > 4294967295:
				raise ValueError('Base85 overflow in hunk starting at byte %d' % i)
				out.append(acc)

				# Pad final chunk if necessary
				cl = l % 5
				if cl:
				acc = 85 * (5 - cl)
				if cl > 1:
				acc += 0xffffff >> (cl - 2) * 8
				out[-1] = acc

				out = struct.pack('>%dL' % (len(out)), *out)
				if cl:
				out = out[:-(5 - cl)]

				return out