--- /dev/null
+#!/usr/bin/perl
+#
+# Copyright (c) 2006 Josh England
+#
+# This script can be used to save/restore full permissions and ownership data
+# within a git working tree.
+#
+# To save permissions/ownership data, place this script in your .git/hooks
+# directory and enable a `pre-commit` hook with the following lines:
+# #!/bin/sh
+# . git-sh-setup
+# $GIT_DIR/hooks/setgitperms.perl -r
+#
+# To restore permissions/ownership data, place this script in your .git/hooks
+# directory and enable a `post-merge` hook with the following lines:
+# #!/bin/sh
+# . git-sh-setup
+# $GIT_DIR/hooks/setgitperms.perl -w
+#
+use strict;
+use Getopt::Long;
+use File::Find;
+use File::Basename;
+
+my $usage =
+"Usage: setgitperms.perl [OPTION]... <--read|--write>
+This program uses a file `.gitmeta` to store/restore permissions and uid/gid
+info for all files/dirs tracked by git in the repository.
+
+---------------------------------Read Mode-------------------------------------
+-r, --read Reads perms/etc from working dir into a .gitmeta file
+-s, --stdout Output to stdout instead of .gitmeta
+-d, --diff Show unified diff of perms file (XOR with --stdout)
+
+---------------------------------Write Mode------------------------------------
+-w, --write Modify perms/etc in working dir to match the .gitmeta file
+-v, --verbose Be verbose
+
+\n";
+
+my ($stdout, $showdiff, $verbose, $read_mode, $write_mode);
+
+if ((@ARGV < 0) || !GetOptions(
+ "stdout", \$stdout,
+ "diff", \$showdiff,
+ "read", \$read_mode,
+ "write", \$write_mode,
+ "verbose", \$verbose,
+ )) { die $usage; }
+die $usage unless ($read_mode xor $write_mode);
+
+my $topdir = `git-rev-parse --show-cdup` or die "\n"; chomp $topdir;
+my $gitdir = $topdir . '.git';
+my $gitmeta = $topdir . '.gitmeta';
+
+if ($write_mode) {
+ # Update the working dir permissions/ownership based on data from .gitmeta
+ open (IN, "<$gitmeta") or die "Could not open $gitmeta for reading: $!\n";
+ while (defined ($_ = <IN>)) {
+ chomp;
+ if (/^(.*) mode=(\S+)\s+uid=(\d+)\s+gid=(\d+)/) {
+ # Compare recorded perms to actual perms in the working dir
+ my ($path, $mode, $uid, $gid) = ($1, $2, $3, $4);
+ my $fullpath = $topdir . $path;
+ my (undef,undef,$wmode,undef,$wuid,$wgid) = lstat($fullpath);
+ $wmode = sprintf "%04o", $wmode & 07777;
+ if ($mode ne $wmode) {
+ $verbose && print "Updating permissions on $path: old=$wmode, new=$mode\n";
+ chmod oct($mode), $fullpath;
+ }
+ if ($uid != $wuid || $gid != $wgid) {
+ if ($verbose) {
+ # Print out user/group names instead of uid/gid
+ my $pwname = getpwuid($uid);
+ my $grpname = getgrgid($gid);
+ my $wpwname = getpwuid($wuid);
+ my $wgrpname = getgrgid($wgid);
+ $pwname = $uid if !defined $pwname;
+ $grpname = $gid if !defined $grpname;
+ $wpwname = $wuid if !defined $wpwname;
+ $wgrpname = $wgid if !defined $wgrpname;
+
+ print "Updating uid/gid on $path: old=$wpwname/$wgrpname, new=$pwname/$grpname\n";
+ }
+ chown $uid, $gid, $fullpath;
+ }
+ }
+ else {
+ warn "Invalid input format in $gitmeta:\n\t$_\n";
+ }
+ }
+ close IN;
+}
+elsif ($read_mode) {
+ # Handle merge conflicts in the .gitperms file
+ if (-e "$gitdir/MERGE_MSG") {
+ if (`grep ====== $gitmeta`) {
+ # Conflict not resolved -- abort the commit
+ print "PERMISSIONS/OWNERSHIP CONFLICT\n";
+ print " Resolve the conflict in the $gitmeta file and then run\n";
+ print " `.git/hooks/setgitperms.perl --write` to reconcile.\n";
+ exit 1;
+ }
+ elsif (`grep $gitmeta $gitdir/MERGE_MSG`) {
+ # A conflict in .gitmeta has been manually resolved. Verify that
+ # the working dir perms matches the current .gitmeta perms for
+ # each file/dir that conflicted.
+ # This is here because a `setgitperms.perl --write` was not
+ # performed due to a merge conflict, so permissions/ownership
+ # may not be consistent with the manually merged .gitmeta file.
+ my @conflict_diff = `git show \$(cat $gitdir/MERGE_HEAD)`;
+ my @conflict_files;
+ my $metadiff = 0;
+
+ # Build a list of files that conflicted from the .gitmeta diff
+ foreach my $line (@conflict_diff) {
+ if ($line =~ m|^diff --git a/$gitmeta b/$gitmeta|) {
+ $metadiff = 1;
+ }
+ elsif ($line =~ /^diff --git/) {
+ $metadiff = 0;
+ }
+ elsif ($metadiff && $line =~ /^\+(.*) mode=/) {
+ push @conflict_files, $1;
+ }
+ }
+
+ # Verify that each conflict file now has permissions consistent
+ # with the .gitmeta file
+ foreach my $file (@conflict_files) {
+ my $absfile = $topdir . $file;
+ my $gm_entry = `grep "^$file mode=" $gitmeta`;
+ if ($gm_entry =~ /mode=(\d+) uid=(\d+) gid=(\d+)/) {
+ my ($gm_mode, $gm_uid, $gm_gid) = ($1, $2, $3);
+ my (undef,undef,$mode,undef,$uid,$gid) = lstat("$absfile");
+ $mode = sprintf("%04o", $mode & 07777);
+ if (($gm_mode ne $mode) || ($gm_uid != $uid)
+ || ($gm_gid != $gid)) {
+ print "PERMISSIONS/OWNERSHIP CONFLICT\n";
+ print " Mismatch found for file: $file\n";
+ print " Run `.git/hooks/setgitperms.perl --write` to reconcile.\n";
+ exit 1;
+ }
+ }
+ else {
+ print "Warning! Permissions/ownership no longer being tracked for file: $file\n";
+ }
+ }
+ }
+ }
+
+ # No merge conflicts -- write out perms/ownership data to .gitmeta file
+ unless ($stdout) {
+ open (OUT, ">$gitmeta.tmp") or die "Could not open $gitmeta.tmp for writing: $!\n";
+ }
+
+ my @files = `git-ls-files`;
+ my %dirs;
+
+ foreach my $path (@files) {
+ chomp $path;
+ # We have to manually add stats for parent directories
+ my $parent = dirname($path);
+ while (!exists $dirs{$parent}) {
+ $dirs{$parent} = 1;
+ next if $parent eq '.';
+ printstats($parent);
+ $parent = dirname($parent);
+ }
+ # Now the git-tracked file
+ printstats($path);
+ }
+
+ # diff the temporary metadata file to see if anything has changed
+ # If no metadata has changed, don't overwrite the real file
+ # This is just so `git commit -a` doesn't try to commit a bogus update
+ unless ($stdout) {
+ if (! -e $gitmeta) {
+ rename "$gitmeta.tmp", $gitmeta;
+ }
+ else {
+ my $diff = `diff -U 0 $gitmeta $gitmeta.tmp`;
+ if ($diff ne '') {
+ rename "$gitmeta.tmp", $gitmeta;
+ }
+ else {
+ unlink "$gitmeta.tmp";
+ }
+ if ($showdiff) {
+ print $diff;
+ }
+ }
+ close OUT;
+ }
+ # Make sure the .gitmeta file is tracked
+ system("git add $gitmeta");
+}
+
+
+sub printstats {
+ my $path = $_[0];
+ $path =~ s/@/\@/g;
+ my (undef,undef,$mode,undef,$uid,$gid) = lstat($path);
+ $path =~ s/%/\%/g;
+ if ($stdout) {
+ print $path;
+ printf " mode=%04o uid=$uid gid=$gid\n", $mode & 07777;
+ }
+ else {
+ print OUT $path;
+ printf OUT " mode=%04o uid=$uid gid=$gid\n", $mode & 07777;
+ }
+}
--- /dev/null
+#!/bin/sh
+#
+# Copyright (c) 2006 Josh England
+#
+
+test_description='Test the post-merge hook.'
+. ./test-lib.sh
+
+test_expect_success setup '
+ echo Data for commit0. >a &&
+ git update-index --add a &&
+ tree0=$(git write-tree) &&
+ commit0=$(echo setup | git commit-tree $tree0) &&
+ echo Changed data for commit1. >a &&
+ git update-index a &&
+ tree1=$(git write-tree) &&
+ commit1=$(echo modify | git commit-tree $tree1 -p $commit0) &&
+ git update-ref refs/heads/master $commit0 &&
+ git-clone ./. clone1 &&
+ GIT_DIR=clone1/.git git update-index --add a &&
+ git-clone ./. clone2 &&
+ GIT_DIR=clone2/.git git update-index --add a
+'
+
+for clone in 1 2; do
+ cat >clone${clone}/.git/hooks/post-merge <<'EOF'
+#!/bin/sh
+echo $@ >> $GIT_DIR/post-merge.args
+EOF
+ chmod u+x clone${clone}/.git/hooks/post-merge
+done
+
+test_expect_failure 'post-merge does not run for up-to-date ' '
+ GIT_DIR=clone1/.git git merge $commit0 &&
+ test -e clone1/.git/post-merge.args
+'
+
+test_expect_success 'post-merge runs as expected ' '
+ GIT_DIR=clone1/.git git merge $commit1 &&
+ test -e clone1/.git/post-merge.args
+'
+
+test_expect_success 'post-merge from normal merge receives the right argument ' '
+ grep 0 clone1/.git/post-merge.args
+'
+
+test_expect_success 'post-merge from squash merge runs as expected ' '
+ GIT_DIR=clone2/.git git merge --squash $commit1 &&
+ test -e clone2/.git/post-merge.args
+'
+
+test_expect_success 'post-merge from squash merge receives the right argument ' '
+ grep 1 clone2/.git/post-merge.args
+'
+
+test_done