# Copyright (C) 2005 Canonical Ltd
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
#
# Author: Martin Pool <mbp@canonical.com>
"""Store and retrieve weaves in files.
There is one format marker followed by a blank line, followed by a
series of version headers, followed by the weave itself.
Each version marker has
'i' parent version indexes
'1' SHA-1 of text
'n' name
The inclusions do not need to list versions included by a parent.
The weave is bracketed by 'w' and 'W' lines, and includes the '{}[]'
processing instructions. Lines of text are prefixed by '.' if the
line contains a newline, or ',' if not.
"""
# TODO: When extracting a single version it'd be enough to just pass
# an iterator returning the weave lines... We don't really need to
# deserialize it into memory.
FORMAT_1 = '# bzr weave file v5\n'
def write_weave(weave, f, format=None):
if format is None or format == 1:
return write_weave_v5(weave, f)
else:
raise ValueError("unknown weave format %r" % format)
def write_weave_v5(weave, f):
"""Write weave to file f."""
f.write(FORMAT_1)
for version, included in enumerate(weave._parents):
if included:
# mininc = weave.minimal_parents(version)
mininc = included
f.write('i ')
f.write(' '.join(str(i) for i in mininc))
f.write('\n')
else:
f.write('i\n')
f.write('1 ' + weave._sha1s[version] + '\n')
f.write('n ' + weave._names[version] + '\n')
f.write('\n')
f.write('w\n')
for l in weave._weave:
if isinstance(l, tuple):
if l[0] == '}':
f.write('}\n')
else:
f.write('%s %d\n' % l)
else: # text line
if not l:
f.write(', \n')
elif l[-1] == '\n':
f.write('. ' + l)
else:
f.write(', ' + l + '\n')
f.write('W\n')
def read_weave(f):
# FIXME: detect the weave type and dispatch
from bzrlib.trace import mutter
from weave import Weave
w = Weave(getattr(f, 'name', None))
_read_weave_v5(f, w)
return w
def _read_weave_v5(f, w):
"""Private helper routine to read a weave format 5 file into memory.
This is only to be used by read_weave and WeaveFile.__init__.
"""
# 200 0 2075.5080 1084.0360 bzrlib.weavefile:104(_read_weave_v5)
# +60412 0 366.5900 366.5900 +<method 'readline' of 'file' objects>
# +59982 0 320.5280 320.5280 +<method 'startswith' of 'str' objects>
# +59363 0 297.8080 297.8080 +<method 'append' of 'list' objects>
# replace readline call with iter over all lines ->
# safe because we already suck on memory.
# 200 0 1492.7170 802.6220 bzrlib.weavefile:104(_read_weave_v5)
# +59982 0 329.9100 329.9100 +<method 'startswith' of 'str' objects>
# +59363 0 320.2980 320.2980 +<method 'append' of 'list' objects>
# replaced startswith with slice lookups:
# 200 0 851.7250 501.1120 bzrlib.weavefile:104(_read_weave_v5)
# +59363 0 311.8780 311.8780 +<method 'append' of 'list' objects>
# +200 0 30.2500 30.2500 +<method 'readlines' of 'file' objects>
from weave import WeaveFormatError
try:
lines = iter(f.readlines())
finally:
f.close()
try:
l = lines.next()
except StopIteration:
raise WeaveFormatError('invalid weave file: no header')
if l != FORMAT_1:
raise WeaveFormatError('invalid weave file header: %r' % l)
ver = 0
# read weave header.
while True:
l = lines.next()
if l[0] == 'i':
if len(l) > 2:
w._parents.append(map(int, l[2:].split(' ')))
else:
w._parents.append([])
l = lines.next()[:-1]
w._sha1s.append(l[2:])
l = lines.next()
name = l[2:-1]
w._names.append(name)
w._name_map[name] = ver
l = lines.next()
ver += 1
elif l == 'w\n':
break
else:
raise WeaveFormatError('unexpected line %r' % l)
# read weave body
while True:
l = lines.next()
if l == 'W\n':
break
elif '. ' == l[0:2]:
w._weave.append(l[2:]) # include newline
elif ', ' == l[0:2]:
w._weave.append(l[2:-1]) # exclude newline
elif l == '}\n':
w._weave.append(('}', None))
else:
w._weave.append((intern(l[0]), int(l[2:])))
return w
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