NineSec Team Shell

#!/usr/bin/perl # # This script lets you update a hierarchy of files in an atomic way by # first creating a new hierarchy using rsync's --link-dest option, and # then swapping the hierarchy into place. **See the usage message for # more details and some important caveats!** use strict; use warnings; use Cwd 'abs_path'; my $RSYNC_PROG = '/usr/bin/rsync'; my $RM_PROG = '/bin/rm'; my $dest_dir = $ARGV[-1]; &usage if !defined $dest_dir || $dest_dir =~ /(^-|^$)/ || grep(/^--help/, @ARGV); $dest_dir =~ s{(?<=.)/+$} {}; if (!-d $dest_dir) { die "$dest_dir is not a directory.\nUse --help for help.\n"; } if (@_ = grep(/^--[a-z]+-dest\b/, @ARGV)) { $_ = join(' or ', @_); die "You cannot use the $_ option with atomic-rsync.\nUse --help for help.\n"; } my $symlink_content = readlink $dest_dir; # undef when a real dir my $dest_arg = $dest_dir; # This gives us the real destination dir, with all symlinks dereferenced. $dest_dir = abs_path($dest_dir); if ($dest_dir eq '/') { die qq|You must not use "/" as the destination directory.\nUse --help for help.\n|; } my($old_dir, $new_dir); if (defined $symlink_content && $dest_dir =~ /-([12])$/) { my $num = 3 - $1; $old_dir = undef; ($new_dir = $dest_dir) =~ s/-[12]$/-$num/; $symlink_content =~ s/-[12]$/-$num/; } else { $old_dir = "$dest_dir~old~"; $new_dir = "$dest_dir~new~"; } $ARGV[-1] = "$new_dir/"; system($RM_PROG, '-rf', $old_dir) if defined $old_dir && -d $old_dir; system($RM_PROG, '-rf', $new_dir) if -d $new_dir; if (system($RSYNC_PROG, "--link-dest=$dest_dir", @ARGV)) { if ($? == -1) { print "failed to execute $RSYNC_PROG: $!\n"; } elsif ($? & 127) { printf "child died with signal %d, %s coredump\n", ($? & 127), ($? & 128) ? 'with' : 'without'; } else { printf "child exited with value %d\n", $? >> 8; } exit $?; } if (!defined $old_dir) { atomic_symlink($symlink_content, $dest_arg); exit; } rename($dest_dir, $old_dir) or die "Unable to rename $dest_dir to $old_dir: $!"; rename($new_dir, $dest_dir) or die "Unable to rename $new_dir to $dest_dir: $!"; exit; sub atomic_symlink { my($target, $link) = @_; my $newlink = "$link~new~"; unlink($newlink); # Just in case symlink($target, $newlink) or die "Unable to symlink $newlink -> $target: $!\n"; rename($newlink, $link) or die "Unable to rename $newlink to $link: $!\n"; } sub usage { die <<EOT; Usage: atomic-rsync [RSYNC-OPTIONS] HOST:/SOURCE/DIR/ /DEST/DIR/ atomic-rsync [RSYNC-OPTIONS] HOST::MOD/DIR/ /DEST/DIR/ This script lets you update a hierarchy of files in an atomic way by first creating a new hierarchy (using hard-links to leverage the existing files), and then swapping the new hierarchy into place. You must be pulling files to a local directory, and that directory must already exist. For example: mkdir /local/files-1 ln -s files-1 /local/files atomic-rsync -av host:/remote/files/ /local/files/ If /local/files is a symlink to a directory that ends in -1 or -2, the copy will go to the alternate suffix and the symlink will be changed to point to the new dir. This is a fully atomic update. If the destination is not a symlink (or not a symlink to a *-1 or a *-2 directory), this will instead create a directory with "~new~" suffixed, move the current directory to a name with "~old~" suffixed, and then move the ~new~ directory to the original destination name (this double rename is not fully atomic, but is rapid). In both cases, the prior destintaion directory will be preserved until the next update, at which point it will be deleted. In all likelihood, you do NOT want to specify this command: atomic-rsync -av host:/remote/files /local/ ... UNLESS you want the entire /local dir to be swapped out! See the "rsync" command for its list of options. You may not use the --link-dest, --compare-dest, or --copy-dest options (since this script uses --link-dest to make the transfer efficient). EOT }

Name	Size	Last Modified	Owner	Permissions	Options
..	--	April 25 2020 3:53:31	root	0755

atomic-rsync	3.901 KB	October 11 2008 6:30:26	root	0755
cull_options	2.386 KB	September 04 2014 10:44:50	root	0755
cvs2includes	1.184 KB	March 21 2007 2:51:54	root	0755
file-attr-restore	4.816 KB	December 20 2006 1:50:17	root	0755
files-to-excludes	0.521 KB	January 30 2006 10:52:17	root	0755
git-set-file-times	0.889 KB	January 13 2009 11:52:03	root	0755
logfilter	1.074 KB	October 04 2005 6:12:28	root	0755
lsh	2.206 KB	June 10 2013 4:40:56	root	0755
mnt-excl	1.801 KB	July 05 2011 1:32:06	root	0755
munge-symlinks	1.428 KB	November 27 2007 4:34:59	root	0755
rrsync	7.069 KB	September 14 2015 1:23:54	root	0755
rsyncstats	8.479 KB	September 01 2023 8:38:04	root	0755

NineSec Team - 2022