marks_file.py

   1 # Copyright (C) 2009 Canonical Ltd
   2 #
   3 # This program is free software; you can redistribute it and/or modify
   4 # it under the terms of the GNU General Public License as published by
   5 # the Free Software Foundation; either version 2 of the License, or
   6 # (at your option) any later version.
   7 #
   8 # This program is distributed in the hope that it will be useful,
   9 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 # GNU General Public License for more details.
  12 #
  13 # You should have received a copy of the GNU General Public License
  14 # along with this program; if not, write to the Free Software
  15 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  16
  17 """Routines for reading/writing a marks file."""
  18
  19
  20 from bzrlib.trace import warning
  21
  22
  23 def import_marks(filename):
  24     """Read the mapping of marks to revision-ids from a file.
  25
  26     :param filename: the file to read from
  27     :return: None if an error is encountered or a dictionary with marks
  28         as keys and revision-ids as values
  29     """
  30     # Check that the file is readable and in the right format
  31     try:
  32         f = file(filename)
  33     except IOError:
  34         warning("Could not import marks file %s - not importing marks",
  35             filename)
  36         return None
  37
  38     # Read the revision info
  39     revision_ids = {}
  40
  41     line = f.readline()
  42     if line == 'format=1\n':
  43         # Cope with old-style marks files
  44         # Read the branch info
  45         branch_names = {}
  46         for string in f.readline().rstrip('\n').split('\0'):
  47             if not string:
  48                 continue
  49             name, integer = string.rsplit('.', 1)
  50             branch_names[name] = int(integer)
  51         line = f.readline()
  52
  53     while line:
  54         line = line.rstrip('\n')
  55         mark, revid = line.split(' ', 1)
  56         mark = mark.lstrip(':')
  57         revision_ids[mark] = revid
  58         line = f.readline()
  59     f.close()
  60     return revision_ids
  61
  62
  63 def export_marks(filename, revision_ids):
  64     """Save marks to a file.
  65
  66     :param filename: filename to save data to
  67     :param revision_ids: dictionary mapping marks -> bzr revision-ids
  68     """
  69     try:
  70         f = file(filename, 'w')
  71     except IOError:
  72         warning("Could not open export-marks file %s - not exporting marks",
  73             filename)
  74         return
  75
  76     # Write the revision info
  77     for mark, revid in revision_ids.iteritems():
  78         f.write(':%s %s\n' % (str(mark).lstrip(':'), revid))
  79     f.close()