# Script to help with fallout from #849041.
#
# usage:
+# dgit-badcommit-fixup --check
# dgit-badcommit-fixup --test
# dgit-badcommit-fixup --real
+# Update procedure, from server operator's point of view:
+#
+# 1. Test in an offline tree that this DTRT
+#
+# 2. Announce a transition time. Tell everyone that between
+# the transition time and their next upload, they must
+# run this script.
+#
+# 3. At the transition time, run this script in every repo.
+#
+# 4. Run the mirror script to push changes, if necessary.
+
+
use strict;
use POSIX;
use IPC::Open2;
use Data::Dumper;
+our $our_version = 'UNRELEASED'; ###substituted###
+
my $real;
foreach my $a (@ARGV) {
$real = 0;
} elsif ($a eq '--real') {
$real = 1;
+ } elsif ($a eq '--check') {
+ $real = -1;
} else {
die "$a ?";
}
die "$? $!" if $?;
chomp $bare or die;
+our @configs;
+foreach my $k (qw(core.sharedRepository)) {
+ $?=0; $!=0; my $v = `set -x; git config --local $k`;
+ if (defined $v && $?==0 && chomp $v) {
+ push @configs, [ $k, $v ];
+ } elsif (defined $v && $?==256 && $v eq '') {
+ } else {
+ die "git-config --local $k => $v $? $! ?";
+ }
+}
+
sub getobj ($$) {
my ($obj, $type) = @_;
print GCFI $obj, "\n" or die $!;
if ($newdata eq $olddata) {
$newobj = $obj;
$count{unchanged}++;
+#print STDERR "UNCHANGED $obj\n";
} else {
$newobj = hashobj $newdata, 'commit';
+#print STDERR "REWRITTEN $obj $newobj\n";
}
$$m= $newobj;
return $newobj;
}
+our @updates;
+
+sub filter_updates () {
+ @updates = grep { $_->[1] ne $_->[2] } @updates;
+}
+
sub rewrite_tag ($) {
my ($obj) = @_;
$_ = getobj $obj, 'tag';
return hashobj $_, 'tag';
}
+sub edit_rewrite_map ($) {
+ my ($old) = @_;
+
+ filter_updates();
+ return $old unless @updates;
+
+ my $td = 'dgit-broken-fixup.tmp';
+ runcmd qw(rm -rf), $td;
+ mkdir $td, 0700 or die "$td $!";
+ chdir $td or die $!;
+ runcmd qw(git init -q);
+ runcmd qw(git config gc.auto 0);
+ runcmd qw(rm -rf .git/objects);
+ symlink "../../objects", ".git/objects" or die $!;
+ foreach my $c (@configs) {
+ runcmd qw(git config), $c->[0], $c->[1];
+ }
+
+ my %map;
+
+ if ($old) {
+ runcmd qw(git checkout -q), $old;
+ open M, "map" or die $!;
+ while (<M>) {
+ m/^(\w+)(?:\s+(\w+))?$/ or die;
+ $map{$1} = $2;
+ $count{rewrite_map_previous}++;
+ }
+ M->error and die $!;
+ close M or die $!;
+ }
+
+ foreach my $oldc (keys %memo) {
+ my $newc = $memo{$oldc};
+ next if $oldc eq $newc;
+ $map{$oldc} = $newc;
+ }
+ foreach my $up (@updates) { # catches tags
+ $map{ $up->[1] } = $up->[2];
+ }
+
+ open M, ">", "map" or die $!;
+ printf M "%s%s\n",
+ $_, (defined $map{$_} ? " $map{$_}" : "")
+ or die $!
+ foreach keys %map;
+ close M or die $!;
+
+ if (!$old) {
+ runcmd qw(git add map);
+ }
+
+ runcmd qw(git commit -q), qw(-m), <<END, qw(map);
+dgit-badcommit-fixup
+
+[dgit-badcommit-fixup $our_version]
+END
+
+ $!=0; $?=0;
+ my $new = `git rev-parse HEAD`;
+ die "$? $!" if $?;
+ chomp $new or die;
+
+ chdir '..' or die $!;
+ runcmd qw(rm -rf), $td;
+
+ $count{rewrite_map_updated}++;
+
+ return $new;
+}
+
$!=0; $?=0;
my $refs=`git for-each-ref`;
die "$? $!" if $?;
chomp $refs;
-our @updates;
+our $org_rewrite_map;
foreach my $rline (split /\n/, $refs) {
my ($obj, $type, $refname) =
$rline =~ m/^(\w+)\s+(\w+)\s+(\S.*)/
or die "$_ ?";
+ if ($refname eq 'refs/dgit-rewrite/map') {
+ $org_rewrite_map = $obj;
+ next;
+ }
+ next if $refname =~ m{^refs/dgit-(?:badcommit|badfixuptest)/};
+
+ $!=0; $?=0;
+ system qw(sh -ec),
+ 'exec >/dev/null git symbolic-ref -q "$1"', qw(x),
+ $refname;
+ if ($?==0) {
+ $count{symrefs_ignored}++;
+ next;
+ }
+ die "$? $!" unless $?==256;
+
my $rewrite;
if ($type eq 'commit') {
$rewrite = rewrite_commit($obj);
warn "ref $refname refers to $type\n";
next;
}
- next if $rewrite eq $obj;
push @updates, [ $refname, $obj, $rewrite ];
}
-our $worktree;
-
-#print Dumper(\@updates);
+if ($bare eq 'true') {
+ my $new_rewrite_map = edit_rewrite_map($org_rewrite_map);
+ push @updates, [ 'refs/dgit-rewrite/map',
+ ($org_rewrite_map // '0'x40),
+ ($new_rewrite_map // '0'x40),
+ 1 ];
+}
-open U, "|git update-ref -m 'dgit bad commit fixup' --stdin" or die $!;
+filter_updates();
-if ($real && $bare eq 'false') {
- print "detaching your HEAD\n" or die $!;
- runcmd 'git checkout --detach';
+if (!@updates) {
+ print Dumper(\%count), "all is well - nothing to do\n";
+ exit 0;
}
+#print Dumper(\@updates);
+
+open U, "|git update-ref -m 'dgit bad commit fixup' --stdin" or die $!
+ if $real >= 0;
+
for my $up (@updates) {
- my ($ref, $old, $new) = @$up;
+ my ($ref, $old, $new, $nobackup) = @$up;
my $otherref = $ref;
$otherref =~ s{^refs/}{};
- if ($real) {
- print U <<END or die $!;
+ if ($real > 0) {
+ print U <<END or die $! unless $nobackup;
create refs/dgit-badcommit/$otherref $old
+END
+ print U <<END or die $!;
update $ref $new $old
END
- } else {
+ } elsif ($real==0) {
print U <<END or die $!;
update refs/dgit-badfixuptest/$otherref $new
END
+ } else {
+ print "found trouble in history of $ref\n" or die $!;
}
}
-$?=0; $!=0;
-close U or die "$? $!";
-die $? if $?;
+if ($real >= 0) {
+ $?=0; $!=0;
+ close U or die "$? $!";
+ die $? if $?;
+}
print Dumper(\%count);
-if ($real) {
+if ($real >= 0) {
print "old values saved in refs/dgit-badcommit/\n" or die $!;
-} else {
+} elsif ($real == 0) {
print "testing output saved in refs/dgit-badfixuptest/\n" or die $!;
+} else {
+ print STDERR "found work to do, exiting status 2\n";
+ exit 2;
}