[file_utils] Add dirpacker.py

This program helps grouping a bunch of files into fixed-size volumes
(e.g. to burn them on CD-ROMs).

bin/dirpacker

@@ -0,0 +1 @@
+../file_utils/dirpacker.py

file_utils/README

@@ -1,3 +1,22 @@
+# dirpacker.py #
+
+This scripts allows to group (pack) a bunch of files or directories into
+fixed-size volumes, optimizing the occupied size of the volumes. The
+original use case was to burn MP3 albums to CD-ROMs to play them in the
+car, but minimize the wasted space of each disc. Of course, it can be
+used to backup any kind of files to any kind of medium.
+
+The particularity of this program, compared for example to datapacker
+(from which it is loosely inspired) is that it works with directories
+instead of regular files only. The files inside a directory won't be
+separated on several archives, they will be on the same volume.
+
+Note: I kept the datapacker's terminology, a volume is also called a
+bin.
+
+To see the usage, call the program with -h.
+
+
 # mvparent.sh #
 
 mvparent.sh was originally written to be integrated in the ROX-Filer

file_utils/dirpacker.py

@@ -0,0 +1,137 @@
+#!/usr/bin/python3
+#
+# dirpacker.py, Copyright © 2014 Matteo Cypriani <mcy@lm7.fr>
+#
+########################################################################
+# This program is licensed under the terms of the Expat license.
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+# IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+# CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+# TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+########################################################################
+#
+# This script groups input files by volumes of a given size. It is loosely
+# inspired by datapacker but is able to work on directories rather than regular
+# files only.
+
+
+import argparse
+import os
+from collections import defaultdict
+import math
+
+
+def du(basepath):
+    """ Returns the size of the file of directory `basepath`, in MiB.
+    """
+    size = os.path.getsize(basepath)
+    for root, dirs, files in os.walk(basepath):
+        for name in files + dirs:
+            fullname = os.path.join(root, name)
+            if not os.path.exists(fullname):
+                continue
+            size += os.path.getsize(fullname)
+    return size / 1024 / 1024
+
+
+def create_bin(binnumber):
+    """Creates a bin numbered `binnumber` from the global list of files and
+    sizes.
+    """
+    print("\n### Bin #{} ###\n# List of files:".format(binnumber))
+    binsize = 0
+    for size in reversed(sorted(sizes.keys())):
+        newbinsize = binsize + size
+        # Try the next, smaller file if we would exceed the bin's maximum size
+        # with this one:
+        if newbinsize > options.maxbinsize:
+            continue
+
+        filename = sizes[size].pop()
+        print("{} # {:.2f} MiB".format(filename, size))
+        # Delete the size from the dictionary if its last file name was just
+        # popped:
+        if not len(sizes[size]):
+            del sizes[size]
+
+        binsize = newbinsize
+
+    print("# This bin's size: {:.2f} MiB".format(binsize))
+    sizefree = options.maxbinsize - binsize
+    print("# Free space: {:.2f} MiB".format(sizefree))
+
+
+### Parse command-line arguments ###
+
+arg_parser = argparse.ArgumentParser(
+    description="Packs files and directories into fixed-size volumes",
+    epilog="For more information about this program, see the README file \
+provided with the distribution.")
+arg_parser.add_argument("-s", "--size", action="store", dest="maxbinsize",
+                        type=float, default=703,
+                        help="maximal size of each volume (bin), in MiB; the "
+                        +"default is 703 MiB, i.e. the size of a 80-minute "
+                        +"CD-ROM")
+arg_parser.add_argument("filenames", metavar="file", nargs="+",
+                        help="files or directories to pack")
+options = arg_parser.parse_args()
+
+
+### Preliminary statistics ###
+
+print("# Maximum size of a bin: {:.2f} MiB".format(options.maxbinsize))
+
+# Compute the size of all the files
+sizes = defaultdict(list)
+totalsize = 0
+ignored_files = False
+for filename in options.filenames:
+    size = du(filename)
+    if (size > options.maxbinsize):
+        print('# WARNING! "{}" is {:.2f} MiB, which exceeds the maximum size of'
+              ' a bin: ignoring.'
+              .format(filename, size))
+        ignored_files = True
+        continue
+    sizes[size].append(filename)
+    totalsize += size
+
+print("# Total size of the input files: {:.2f} MiB".format(totalsize))
+minbins = math.ceil(totalsize / options.maxbinsize)
+print("# Minimal (optimal) number of bins required: ", minbins)
+sizefree = minbins * options.maxbinsize - totalsize
+print("# Total unused space with {} bins: {:.2f} MiB".format(minbins, sizefree))
+
+
+### Assemble the bins ###
+
+binnumber = 1
+while len(sizes):
+    create_bin(binnumber)
+    binnumber += 1
+binscreated = binnumber - 1
+
+
+### Final statistics ###
+
+sizefree = binscreated * options.maxbinsize - totalsize
+print("\n# Total unused space over the {} bins created: {:.2f} MiB"
+      .format(binscreated, sizefree))
+
+if (ignored_files):
+    print("\n# WARNING! There were ignored files, see at the top of this log.")

multimedia/README

@@ -117,3 +117,7 @@ they will be converted recursively and put in the target directory
 (~/tmp/mp3car/ by default, edit the script to change that).
 
 You must have installed pacpl and lame for this script to work.
+
+Note: if you want to burn all these converted audio files to CD-ROMs,
+you might be interested in the dirpacker.py script provided in this
+repository.