dgit-badcommit-fixup: Bugfixes

[dgit.git] / dgit-badcommit-fixup

diff --git a/dgit-badcommit-fixup b/dgit-badcommit-fixup
index f507e48c28072bfcb5e4cfb1ff7c1ba3af622ff0..bab8605aed270ea83d96f8f3c47ea8896b96fd10 100755 (executable)
--- a/dgit-badcommit-fixup
+++ b/dgit-badcommit-fixup
@@ -79,6 +79,7 @@ sub rewrite_commit ($) {
     my $m = \ $memo{$obj};
     return $$m if defined $$m;
     my $olddata = getobj $obj, 'commit';
+#print STDERR ">$obj|$olddata<\n";
     $olddata =~ m/(?<=\n)(?=\n)/ or die "$obj ?";
     my $msg = $';
     local $_ = $`;
@@ -104,10 +105,36 @@ sub rewrite_commit ($) {
     return $newobj;
 }
 
-sub rewrite_commit_adddummy ($$$) {
-    my ($ref, $veryold, $old) = @_;
+our @updates;
+
+sub filter_updates () {
+    @updates = grep { $_->[1] ne $_->[2] } @updates;
+}
+
+sub rewrite_tag ($) {
+    my ($obj) = @_;
+    $_ = getobj $obj, 'tag';
+    m/^type (\w+)\n/m or die "$obj ?";
+    if ($1 ne 'commit') {
+       $count{"oddtags $1"}++;
+       return $obj;
+    }
+    m/^object (\w+)\n/m or die "$obj ?";
+    my $oldref = $1;
+    my $newref = rewrite_commit $oldref;
+    if ($oldref eq $newref) {
+       return $obj;
+    }
+    s/^(object )\w+$/ $1.$newref /me or die "$obj ($_) ?";
+    s/^-----BEGIN PGP SIGNATURE-----\n.*^-----END PGP SIGNATURE-----\n$//sm;
+    return hashobj $_, 'tag';
+}
+
+sub edit_rewrite_map ($) {
+    my ($old) = @_;
 
-    die "$bare ?" unless $bare eq 'true';
+    filter_updates();
+    return $old unless @updates;
 
     my $td = 'dgit-broken-fixup.tmp';
     runcmd qw(rm -rf), $td;
@@ -117,45 +144,39 @@ sub rewrite_commit_adddummy ($$$) {
     runcmd qw(git config gc.auto 0);
     runcmd qw(rm -rf .git/objects);
     symlink "../../objects", ".git/objects" or die $!;
-    runcmd qw(git checkout -q), $old;
 
-    open C, "debian/changelog" or die $!;
-    my $clog = do {
-       local $/ = undef;
-       <C>;
-    };
-    C->error and die $!;
-    close C or die $!;
-    defined $clog or die $!;
+    my %map;
 
-    $!=0; $?=0;
-    my $v = `dpkg-parsechangelog`;
-    die "$ref $veryold $old $? $!" if $?;
-    $v =~ m/^Source: (\S+)$/m or die "$ref $veryold $old ?";
-    my $pkg = $1;
-    $v =~ m/^Version: (\S+)$/m or die "$ref $veryold $old ?";
-    my $vsn = $1;
-    $vsn .= "+~dgitfix";
-
-    open C, ">", "debian/changelog" or die $!;
-    print C <<END;
-$pkg ($vsn) UNRELEASED; urgency=low
+    if ($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 $!;
+    }
 
-  * Additional commit, with slightly incremented version number,
-    to override bad commits generated by dgit due to #849041.
-  * No changes to the package.
-  * Not uploaded anywhere.
+    foreach my $up (@updates) {
+       $map{ $up->[1] } = $up->[2];
+    }
 
- -- Ian Jackson <ijackson\@chiark.greenend.org.uk>  Thu, 05 Jan 2017 17:58:21 +0000
+    open M, ">", "map" or die $!;
+    printf M "%s%s\n",
+       $_, (defined $map{$_} ? " $map{$_}" : "")
+       or die $!
+       foreach keys %map;
+    close M or die $!;
 
-END
-    print C $clog or die $!;
-    close C or die $!;
+    if (!$old) {
+       runcmd qw(git add map);
+    }
 
     runcmd qw(git commit -q), 
-       '--author=Ian Jackson <ijackson@chiark.greenend.org.uk>',
-       qw(-m), 'Dummy changelog entry to work around #849041 fallout',
-       qw(debian/changelog);
+       qw(-m), 'dgit-badcommit-fixup',
+       qw(map);
 
     $!=0; $?=0;
     my $new = `git rev-parse HEAD`;
@@ -165,60 +186,53 @@ END
     chdir '..' or die $!;
     runcmd qw(rm -rf), $td;
 
-    $count{dummyadded}++;
+    $count{rewrite_map_updated}++;
 
     return $new;
 }
 
-sub rewrite_tag ($) {
-    my ($obj) = @_;
-    $_ = getobj $obj, 'tag';
-    m/^type (\w+)\n/m or die "$obj ?";
-    if ($1 ne 'commit') {
-       $count{"oddtags $1"}++;
-       return $obj;
-    }
-    m/^object (\w+)\n/m or die "$obj ?";
-    my $oldref = $1;
-    my $newref = rewrite_commit $oldref;
-    if ($oldref eq $newref) {
-       return $obj;
-    }
-    s/^(object )\w+$/ $1.$newref /me or die "$obj ($_) ?";
-    s/^-----BEGIN PGP SIGNATURE-----\n.*^-----END PGP SIGNATURE-----\n$//sm;
-    return hashobj $_, 'tag';
-}
-
 $!=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;
+       continue;
+    }
     my $rewrite;
     if ($type eq 'commit') {
        $rewrite = rewrite_commit($obj);
-       if ($refname =~ m{^refs/dgit/[^/]+$} &&
-          $rewrite ne $obj) {
-           $rewrite = rewrite_commit_adddummy $refname, $obj, $rewrite;
-       }
     } elsif ($type eq 'tag') {
        $rewrite = rewrite_tag($obj);
     } else {
        warn "ref $refname refers to $type\n";
        next;
     }
-    next if $rewrite eq $obj;
     push @updates, [ $refname, $obj, $rewrite ];
 }
 
-our $worktree;
+if ($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 ];
+}
+
+filter_updates();
+
+if (!@updates) {
+    print Dumper(\%count), "nothing to do\n";
+    exit 0;
+}
 
 #print Dumper(\@updates);
 
@@ -230,12 +244,14 @@ if ($real && $bare eq 'false') {
 }
 
 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 $!;
+       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 {