+def parse_changes(filename, signing_rules=0):
+ """Parses a changes file and returns a dictionary where each field is a
+key. The mandatory first argument is the filename of the .changes
+file.
+
+signing_rules is an optional argument:
+
+ o If signing_rules == -1, no signature is required.
+ o If signing_rules == 0 (the default), a signature is required.
+ o If signing_rules == 1, it turns on the same strict format checking
+ as dpkg-source.
+
+The rules for (signing_rules == 1)-mode are:
+
+ o The PGP header consists of "-----BEGIN PGP SIGNED MESSAGE-----"
+ followed by any PGP header data and must end with a blank line.
+
+ o The data section must end with a blank line and must be followed by
+ "-----BEGIN PGP SIGNATURE-----".
+"""
+
+ changes_in = open_file(filename)
+ content = changes_in.read()
+ changes_in.close()
+ return parse_deb822(content, signing_rules)
+
+################################################################################
+
+def hash_key(hashname):
+ return '%ssum' % hashname
+
+################################################################################
+
+def create_hash(where, files, hashname, hashfunc):
+ """create_hash extends the passed files dict with the given hash by
+ iterating over all files on disk and passing them to the hashing
+ function given."""
+