From: Zygo Blaxell <zblaxell@faye.furryterror.org>
Date: Fri, 14 May 2010 16:39:36 +0000 (-0400)
Subject: dm6: use Base64 encoding for inode numbers
X-Git-Tag: dm6-0.20100514~5^2~1
X-Git-Url: http://git.hungrycats.org/cgi-bin/gitweb.cgi?p=dupemerge;a=commitdiff_plain;h=f33f401917c7c40b17b3667fc8f29133e77c6523;ds=sidebyside

dm6: use Base64 encoding for inode numbers
---

diff --git a/dm6 b/dm6
index 44dcb91..a25804b 100755
--- a/dm6
+++ b/dm6
@@ -7,6 +7,7 @@ use File::Compare;
 use File::Path;
 use File::Temp;
 use File::stat;
+use MIME::Base64;
 
 # Copyright (C) 2010 Zygo Blaxell <dm5@mailtoo.hungrycats.org>
 
@@ -103,6 +104,22 @@ sub prepare_parents {
 	return "$parent/$suffix";
 }
 
+sub name_quad {
+	my ($int64) = @_;
+	my $packed = pack('Q', $int64);
+	$packed =~ s/^\0+//os;
+	my $base64_packed = encode_base64($packed, '');
+	# Don't strip off the trailing padding since it makes the string
+	# so short we end up just putting it back on again.
+	# $base64_packed =~ s/=+$//os;
+	return $base64_packed;
+}
+
+sub name_ino {
+	my ($ino) = @_;
+	return name_quad($ino) . 'I';
+}
+
 # ext3 cannot handle more than 32000 links to a file.  Leave some headroom.
 # Arguably this should be configurable, but the losses are miniscule and
 # the coding for option support is not.
@@ -127,7 +144,7 @@ while (<STDIN>) {
 			next if ($st->nlink > $link_count_max);
 
 			# Check link to inode
-			my $inode_link = prepare_parents($link_dir, $st->ino . 'I');
+			my $inode_link = prepare_parents($link_dir, name_ino($st->ino));
 			print STDERR 'I';
 			my $inode_st = lstat($inode_link);
 			my $update_links;
@@ -191,7 +208,7 @@ while (<STDIN>) {
 			}
 
 			# A link to the inode indicates we are done, so do it last
-			$inode_link = prepare_parents($link_dir, "${keep_ino}I");
+			$inode_link = prepare_parents($link_dir, name_ino($keep_ino));
 			print STDERR ' ';
 			link_files($digest_link, $inode_link);