stgit/utils.py

   1 """Common utility functions
   2 """
   3
   4 import errno, os, os.path, re, sys
   5 from stgit.config import config
   6
   7 __copyright__ = """
   8 Copyright (C) 2005, Catalin Marinas <catalin.marinas@gmail.com>
   9
  10 This program is free software; you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License version 2 as
  12 published by the Free Software Foundation.
  13
  14 This program is distributed in the hope that it will be useful,
  15 but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 GNU General Public License for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with this program; if not, write to the Free Software
  21 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22 """
  23
  24 def mkdir_file(filename, mode):
  25     """Opens filename with the given mode, creating the directory it's
  26     in if it doesn't already exist."""
  27     create_dirs(os.path.dirname(filename))
  28     return file(filename, mode)
  29
  30 def read_string(filename, multiline = False):
  31     """Reads the first line from a file
  32     """
  33     f = file(filename, 'r')
  34     if multiline:
  35         result = f.read()
  36     else:
  37         result = f.readline().strip()
  38     f.close()
  39     return result
  40
  41 def write_string(filename, line, multiline = False):
  42     """Writes 'line' to file and truncates it
  43     """
  44     f = mkdir_file(filename, 'w+')
  45     if multiline:
  46         f.write(line)
  47     else:
  48         print >> f, line
  49     f.close()
  50
  51 def append_strings(filename, lines):
  52     """Appends 'lines' sequence to file
  53     """
  54     f = mkdir_file(filename, 'a+')
  55     for line in lines:
  56         print >> f, line
  57     f.close()
  58
  59 def append_string(filename, line):
  60     """Appends 'line' to file
  61     """
  62     f = mkdir_file(filename, 'a+')
  63     print >> f, line
  64     f.close()
  65
  66 def insert_string(filename, line):
  67     """Inserts 'line' at the beginning of the file
  68     """
  69     f = mkdir_file(filename, 'r+')
  70     lines = f.readlines()
  71     f.seek(0); f.truncate()
  72     print >> f, line
  73     f.writelines(lines)
  74     f.close()
  75
  76 def create_empty_file(name):
  77     """Creates an empty file
  78     """
  79     mkdir_file(name, 'w+').close()
  80
  81 def list_files_and_dirs(path):
  82     """Return the sets of filenames and directory names in a
  83     directory."""
  84     files, dirs = [], []
  85     for fd in os.listdir(path):
  86         full_fd = os.path.join(path, fd)
  87         if os.path.isfile(full_fd):
  88             files.append(fd)
  89         elif os.path.isdir(full_fd):
  90             dirs.append(fd)
  91     return files, dirs
  92
  93 def walk_tree(basedir):
  94     """Starting in the given directory, iterate through all its
  95     subdirectories. For each subdirectory, yield the name of the
  96     subdirectory (relative to the base directory), the list of
  97     filenames in the subdirectory, and the list of directory names in
  98     the subdirectory."""
  99     subdirs = ['']
 100     while subdirs:
 101         subdir = subdirs.pop()
 102         files, dirs = list_files_and_dirs(os.path.join(basedir, subdir))
 103         for d in dirs:
 104             subdirs.append(os.path.join(subdir, d))
 105         yield subdir, files, dirs
 106
 107 def strip_prefix(prefix, string):
 108     """Return string, without the prefix. Blow up if string doesn't
 109     start with prefix."""
 110     assert string.startswith(prefix)
 111     return string[len(prefix):]
 112
 113 def strip_suffix(suffix, string):
 114     """Return string, without the suffix. Blow up if string doesn't
 115     end with suffix."""
 116     assert string.endswith(suffix)
 117     return string[:-len(suffix)]
 118
 119 def remove_file_and_dirs(basedir, file):
 120     """Remove join(basedir, file), and then remove the directory it
 121     was in if empty, and try the same with its parent, until we find a
 122     nonempty directory or reach basedir."""
 123     os.remove(os.path.join(basedir, file))
 124     try:
 125         os.removedirs(os.path.join(basedir, os.path.dirname(file)))
 126     except OSError:
 127         # file's parent dir may not be empty after removal
 128         pass
 129
 130 def create_dirs(directory):
 131     """Create the given directory, if the path doesn't already exist."""
 132     if directory and not os.path.isdir(directory):
 133         create_dirs(os.path.dirname(directory))
 134         try:
 135             os.mkdir(directory)
 136         except OSError, e:
 137             if e.errno != errno.EEXIST:
 138                 raise e
 139
 140 def rename(basedir, file1, file2):
 141     """Rename join(basedir, file1) to join(basedir, file2), not
 142     leaving any empty directories behind and creating any directories
 143     necessary."""
 144     full_file2 = os.path.join(basedir, file2)
 145     create_dirs(os.path.dirname(full_file2))
 146     os.rename(os.path.join(basedir, file1), full_file2)
 147     try:
 148         os.removedirs(os.path.join(basedir, os.path.dirname(file1)))
 149     except OSError:
 150         # file1's parent dir may not be empty after move
 151         pass
 152
 153 class EditorException(Exception):
 154     pass
 155
 156 def call_editor(filename):
 157     """Run the editor on the specified filename."""
 158
 159     # the editor
 160     editor = config.get('stgit.editor')
 161     if editor:
 162         pass
 163     elif 'EDITOR' in os.environ:
 164         editor = os.environ['EDITOR']
 165     else:
 166         editor = 'vi'
 167     editor += ' %s' % filename
 168
 169     print 'Invoking the editor: "%s"...' % editor,
 170     sys.stdout.flush()
 171     err = os.system(editor)
 172     if err:
 173         raise EditorException, 'editor failed, exit code: %d' % err
 174     print 'done'
 175
 176 def patch_name_from_msg(msg):
 177     """Return a string to be used as a patch name. This is generated
 178     from the top line of the string passed as argument, and is at most
 179     30 characters long."""
 180     if not msg:
 181         return None
 182
 183     subject_line = msg.split('\n', 1)[0].lstrip().lower()
 184     return re.sub('[\W]+', '-', subject_line).strip('-')[:30]
 185
 186 def make_patch_name(msg, unacceptable, default_name = 'patch',
 187                     alternative = True):
 188     """Return a patch name generated from the given commit message,
 189     guaranteed to make unacceptable(name) be false. If the commit
 190     message is empty, base the name on default_name instead."""
 191     patchname = patch_name_from_msg(msg)
 192     if not patchname:
 193         patchname = default_name
 194     if alternative and unacceptable(patchname):
 195         suffix = 0
 196         while unacceptable('%s-%d' % (patchname, suffix)):
 197             suffix += 1
 198         patchname = '%s-%d' % (patchname, suffix)
 199     return patchname