Add tarsum binary

bin/tarsum

@@ -0,0 +1,90 @@
+#! /usr/bin/env python
+
+# Copyright (C) 2008-2009 by Guy Rutenberg
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the
+# Free Software Foundation, Inc.,
+# 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+
+import hashlib
+import tarfile
+
+
+def tarsum(input_file, hash, output_file):
+    """
+        input_file  - A FILE object to read the tar file from.
+        hash - The name of the hash to use. Must be supported by hashlib.
+        output_file - A FILE to write the computed signatures to.
+        """
+    tar = tarfile.open(mode="r|*", fileobj=input_file)
+
+    chunk_size = 100 * 1024
+    store_digests = {}
+
+    for member in tar:
+        if not member.isfile():
+            continue
+        f = tar.extractfile(member)
+        h = hashlib.new(hash)
+        data = f.read(chunk_size)
+        while data:
+            h.update(data)
+            data = f.read(chunk_size)
+        output_file.write("%s  %s\n" % (h.hexdigest(), member.name))
+
+
+def main():
+    parser = OptionParser()
+
+    version = (
+        "%prog 0.2.1\n"
+        "Copyright (C) 2008-2009 Guy Rutenberg <http://www.guyrutenberg.com/contact-me>"
+    )
+    usage = ("%prog [options] TARFILE\n"
+             "Print a checksum signature for every file in TARFILE.\n"
+             "With no FILE, or when FILE is -, read standard input.")
+    parser = OptionParser(usage=usage, version=version)
+    parser.add_option(
+        "-c",
+        "--checksum",
+        dest="checksum",
+        type="string",
+        help="use HASH as for caclculating the checksums. [default: %default]",
+        metavar="HASH",
+        default="md5")
+    parser.add_option("-o",
+                      "--output",
+                      dest="output",
+                      type="string",
+                      help="save signatures to FILE.",
+                      metavar="FILE")
+
+    (option, args) = parser.parse_args()
+
+    output_file = sys.stdout
+    if option.output:
+        output_file = open(option.output, "w")
+
+    input_file = sys.stdin
+    if len(args) == 1 and args[0] != "-":
+        input_file = open(args[0], "r")
+
+    tarsum(input_file, option.checksum, output_file)
+
+
+if __name__ == "__main__":
+    from optparse import OptionParser
+    import sys
+
+main()