Girts: New page:

 #!/usr/bin/env python # # change-svn-wc-format.py: Change the format of a Subversion working copy. # # ==================================================================== #    Licen...

2009-11-15T18:54:19Z

New page: <pre> #!/usr/bin/env python # # change-svn-wc-format.py: Change the format of a Subversion working copy. # # ==================================================================== # Licen...

New page

<pre>
#!/usr/bin/env python
#
# change-svn-wc-format.py: Change the format of a Subversion working copy.
#
# ====================================================================
# Licensed to the Subversion Corporation (SVN Corp.) under one
# or more contributor license agreements. See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership. The SVN Corp. licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied. See the License for the
# specific language governing permissions and limitations
# under the License.
# ====================================================================

import sys
import os
import getopt
try:
my_getopt = getopt.gnu_getopt
except AttributeError:
my_getopt = getopt.getopt

### The entries file parser in subversion/tests/cmdline/svntest/entry.py
### handles the XML-based WC entries file format used by Subversion
### 1.3 and lower. It could be rolled into this script.

LATEST_FORMATS = { "1.4" : 8,
"1.5" : 9,
"1.6" : 10,
# Do NOT add format 11 here. See comment in must_retain_fields
# for why.
}

def usage_and_exit(error_msg=None):
"""Write usage information and exit. If ERROR_MSG is provide, that
error message is printed first (to stderr), the usage info goes to
stderr, and the script exits with a non-zero status. Otherwise,
usage info goes to stdout and the script exits with a zero status."""
progname = os.path.basename(sys.argv[0])

stream = error_msg and sys.stderr or sys.stdout
if error_msg:
stream.write("ERROR: %s\n\n" % error_msg)
stream.write("""\
usage: %s WC_PATH SVN_VERSION [--verbose] [--force] [--skip-unknown-format]
%s --help

Change the format of a Subversion working copy to that of SVN_VERSION.

--skip-unknown-format : skip directories with unknown working copy
format and continue the update

""" % (progname, progname))
stream.flush()
sys.exit(error_msg and 1 or 0)

def get_adm_dir():
"""Return the name of Subversion's administrative directory,
adjusted for the SVN_ASP_DOT_NET_HACK environment variable. See
<http://svn.collab.net/repos/svn/trunk/notes/asp-dot-net-hack.txt>
for details."""
return "SVN_ASP_DOT_NET_HACK" in os.environ and "_svn" or ".svn"

class WCFormatConverter:
"Performs WC format conversions."
root_path = None
error_on_unrecognized = True
force = False
verbosity = 0

def write_dir_format(self, format_nbr, dirname, paths):
"""Attempt to write the WC format FORMAT_NBR to the entries file
for DIRNAME. Throws LossyConversionException when not in --force
mode, and unconvertable WC data is encountered."""

# Avoid iterating in unversioned directories.
if not (get_adm_dir() in paths):
del paths[:]
return

# Process the entries file for this versioned directory.
if self.verbosity:
print("Processing directory '%s'" % dirname)
entries = Entries(os.path.join(dirname, get_adm_dir(), "entries"))
entries_parsed = True
if self.verbosity:
print("Parsing file '%s'" % entries.path)
try:
entries.parse(self.verbosity)
except UnrecognizedWCFormatException, e:
if self.error_on_unrecognized:
raise
sys.stderr.write("%s, skipping\n" % e)
sys.stderr.flush()
entries_parsed = False

if entries_parsed:
format = Format(os.path.join(dirname, get_adm_dir(), "format"))
if self.verbosity:
print("Updating file '%s'" % format.path)
format.write_format(format_nbr, self.verbosity)
else:
if self.verbosity:
print("Skipping file '%s'" % format.path)

if self.verbosity:
print("Checking whether WC format can be converted")
try:
entries.assert_valid_format(format_nbr, self.verbosity)
except LossyConversionException, e:
# In --force mode, ignore complaints about lossy conversion.
if self.force:
print("WARNING: WC format conversion will be lossy. Dropping "\
"field(s) %s " % ", ".join(e.lossy_fields))
else:
raise

if self.verbosity:
print("Writing WC format")
entries.write_format(format_nbr)

def change_wc_format(self, format_nbr):
"""Walk all paths in a WC tree, and change their format to
FORMAT_NBR. Throw LossyConversionException or NotImplementedError
if the WC format should not be converted, or is unrecognized."""
for dirpath, dirs, files in os.walk(self.root_path):
self.write_dir_format(format_nbr, dirpath, dirs + files)

class Entries:
"""Represents a .svn/entries file.

'The entries file' section in subversion/libsvn_wc/README is a
useful reference."""

# The name and index of each field composing an entry's record.
entry_fields = (
"name",
"kind",
"revision",
"url",
"repos",
"schedule",
"text-time",
"checksum",
"committed-date",
"committed-rev",
"last-author",
"has-props",
"has-prop-mods",
"cachable-props",
"present-props",
"conflict-old",
"conflict-new",
"conflict-wrk",
"prop-reject-file",
"copied",
"copyfrom-url",
"copyfrom-rev",
"deleted",
"absent",
"incomplete",
"uuid",
"lock-token",
"lock-owner",
"lock-comment",
"lock-creation-date",
"changelist",
"keep-local",
"working-size",
"depth",
"tree-conflicts",
"file-external",
)

# The format number.
format_nbr = -1

# How many bytes the format number takes in the file. (The format number
# may have leading zeroes after using this script to convert format 10 to
# format 9 -- which would write the format number as '09'.)
format_nbr_bytes = -1

def __init__(self, path):
self.path = path
self.entries = []

def parse(self, verbosity=0):
"""Parse the entries file. Throw NotImplementedError if the WC
format is unrecognized."""

input = open(self.path, "r")

# Read WC format number from INPUT. Validate that it
# is a supported format for conversion.
format_line = input.readline()
try:
self.format_nbr = int(format_line)
self.format_nbr_bytes = len(format_line.rstrip()) # remove '\n'
except ValueError:
self.format_nbr = -1
self.format_nbr_bytes = -1
if not self.format_nbr in LATEST_FORMATS.values():
raise UnrecognizedWCFormatException(self.format_nbr, self.path)

# Parse file into individual entries, to later inspect for
# non-convertable data.
entry = None
while True:
entry = self.parse_entry(input, verbosity)
if entry is None:
break
self.entries.append(entry)

input.close()

def assert_valid_format(self, format_nbr, verbosity=0):
if verbosity >= 2:
print("Validating format for entries file '%s'" % self.path)
for entry in self.entries:
if verbosity >= 3:
print("Validating format for entry '%s'" % entry.get_name())
try:
entry.assert_valid_format(format_nbr)
except LossyConversionException:
if verbosity >= 3:
sys.stderr.write("Offending entry:\n%s\n" % entry)
sys.stderr.flush()
raise

def parse_entry(self, input, verbosity=0):
"Read an individual entry from INPUT stream."
entry = None

while True:
line = input.readline()
if line in ("", "\x0c\n"):
# EOF or end of entry terminator encountered.
break

if entry is None:
entry = Entry()

# Retain the field value, ditching its field terminator ("\x0a").
entry.fields.append(line[:-1])

if entry is not None and verbosity >= 3:
sys.stdout.write(str(entry))
print("-" * 76)
return entry

def write_format(self, format_nbr):
# Overwrite all bytes of the format number (which are the first bytes in
# the file). Overwrite format '10' by format '09', which will be converted
# to '9' by Subversion when it rewrites the file. (Subversion 1.4 and later
# ignore leading zeroes in the format number.)
assert len(str(format_nbr)) <= self.format_nbr_bytes
format_string = '%0' + str(self.format_nbr_bytes) + 'd'

os.chmod(self.path, 0600)
output = open(self.path, "r+", 0)
output.write(format_string % format_nbr)
output.close()
os.chmod(self.path, 0400)

class Entry:
"Describes an entry in a WC."

# Maps format numbers to indices of fields within an entry's record that must
# be retained when downgrading to that format.
must_retain_fields = {
# Not in 1.4: changelist, keep-local, depth, tree-conflicts, file-externals
8 : (30, 31, 33, 34, 35),
# Not in 1.5: tree-conflicts, file-externals
9 : (34, 35),
10 : (),
# Downgrading from format 11 (1.7-dev) to format 10 is not possible,
# because 11 does not use has-props and cachable-props (but 10 does).
# Naively downgrading in that situation causes properties to disappear
# from the wc.
#
# Downgrading from the 1.7 SQLite-based format to format 10 is not
# implemented.
}

def __init__(self):
self.fields = []

def assert_valid_format(self, format_nbr):
"Assure that conversion will be non-lossy by examining fields."

# Check whether lossy conversion is being attempted.
lossy_fields = []
for field_index in self.must_retain_fields[format_nbr]:
if len(self.fields) - 1 >= field_index and self.fields[field_index]:
lossy_fields.append(Entries.entry_fields[field_index])
if lossy_fields:
raise LossyConversionException(lossy_fields,
"Lossy WC format conversion requested for entry '%s'\n"
"Data for the following field(s) is unsupported by older versions "
"of\nSubversion, and is likely to be subsequently discarded, and/or "
"have\nunexpected side-effects: %s\n\n"
"WC format conversion was cancelled, use the --force option to "
"override\nthe default behavior."
% (self.get_name(), ", ".join(lossy_fields)))

def get_name(self):
"Return the name of this entry."
return len(self.fields) > 0 and self.fields[0] or ""

def __str__(self):
"Return all fields from this entry as a multi-line string."
rep = ""
for i in range(0, len(self.fields)):
rep += "[%s] %s\n" % (Entries.entry_fields[i], self.fields[i])
return rep

class Format:
"""Represents a .svn/format file."""

def __init__(self, path):
self.path = path

def write_format(self, format_nbr, verbosity=0):
format_string = '%d\n'
if os.path.exists(self.path):
if verbosity >= 1:
print("%s will be updated." % self.path)
os.chmod(self.path,0600)
else:
if verbosity >= 1:
print("%s does not exist, creating it." % self.path)
format = open(self.path, "w")
format.write(format_string % format_nbr)
format.close()
os.chmod(self.path, 0400)

class LocalException(Exception):
"""Root of local exception class hierarchy."""
pass

class LossyConversionException(LocalException):
"Exception thrown when a lossy WC format conversion is requested."
def __init__(self, lossy_fields, str):
self.lossy_fields = lossy_fields
self.str = str
def __str__(self):
return self.str

class UnrecognizedWCFormatException(LocalException):
def __init__(self, format, path):
self.format = format
self.path = path
def __str__(self):
return ("Unrecognized WC format %d in '%s'; "
"only formats 8, 9, and 10 can be supported") % (self.format, self.path)

def main():
try:
opts, args = my_getopt(sys.argv[1:], "vh?",
["debug", "force", "skip-unknown-format",
"verbose", "help"])
except:
usage_and_exit("Unable to process arguments/options")

converter = WCFormatConverter()

# Process arguments.
if len(args) == 2:
converter.root_path = args[0]
svn_version = args[1]
else:
usage_and_exit()

# Process options.
debug = False
for opt, value in opts:
if opt in ("--help", "-h", "-?"):
usage_and_exit()
elif opt == "--force":
converter.force = True
elif opt == "--skip-unknown-format":
converter.error_on_unrecognized = False
elif opt in ("--verbose", "-v"):
converter.verbosity += 1
elif opt == "--debug":
debug = True
else:
usage_and_exit("Unknown option '%s'" % opt)

try:
new_format_nbr = LATEST_FORMATS[svn_version]
except KeyError:
usage_and_exit("Unsupported version number '%s'; "
"only 1.4, 1.5, and 1.6 can be supported" % svn_version)

try:
converter.change_wc_format(new_format_nbr)
except LocalException, e:
if debug:
raise
sys.stderr.write("%s\n" % e)
sys.stderr.flush()
sys.exit(1)

print("Converted WC at '%s' into format %d for Subversion %s" % \
(converter.root_path, new_format_nbr, svn_version))

if __name__ == "__main__":
main()
</pre>

Change-svn-wc-format.py - Revision history

Girts: New page:
#!/usr/bin/env python # # change-svn-wc-format.py: Change the format of a Subversion working copy. # # ==================================================================== # Licen...