diff options
Diffstat (limited to 'genbackupdatalib/names.py')
| -rw-r--r-- | genbackupdatalib/names.py | 41 |
1 files changed, 39 insertions, 2 deletions
diff --git a/genbackupdatalib/names.py b/genbackupdatalib/names.py index 8cca24c..02a47ef 100644 --- a/genbackupdatalib/names.py +++ b/genbackupdatalib/names.py @@ -19,12 +19,49 @@ import os class NameGenerator(object): - '''Generate names for new output files.''' + '''Generate names for new output files. - def __init__(self, dirname): + If the target directory is empty, the sequence of output files is + always the same for the same parameters. + + A directory structure is also generated. The shape of the tree is + defined by two parameters: 'max' and 'depth'. 'depth' is the number + of levels of subdirectories to create, and 'max' is the maximum + number of files/dirs to allow per output directory. Thus, if max is + 3 and depth is 2, the output files are: 0/0/0, 0/0/1, 0/0/2, + 0/1/0, 0/1/1, etc. + + If depth is zero, all output files go directly to the target + directory, and max is ignored. + + ''' + + def __init__(self, dirname, depth, max): self.dirname = dirname + self.depth = depth + self.max = max self.counter = 0 + def _path_tuple(self, n): + '''Return tuple for dir/file numbers for nth output file. + + The last item in the tuple gives the file number, the precding + items the directory numbers. Thus, a tuple (1, 2, 3) would + mean path '1/2/3', but it is given as a tuple for easier + manipulation. + + ''' + + if self.depth == 0: + return (n,) + else: + items = [] + for i in range(self.depth + 1): # +1 for filenames + items.append(n % self.max) + n /= self.max + items.reverse() + return tuple(items) + def _next_candidate_name(self): self.counter += 1 return os.path.join(self.dirname, 'file%d' % self.counter) |