lei_mirror: avoid dir/file conflicts in update-ref

[public-inbox.git] / lib / PublicInbox / LeiMirror.pm

diff --git a/lib/PublicInbox/LeiMirror.pm b/lib/PublicInbox/LeiMirror.pm
index 3101336002378ce2ffe1d848b08daa311621a3cc..d959b6b61ac4cd018b1142681d663261846596b6 100644 (file)
--- a/lib/PublicInbox/LeiMirror.pm
+++ b/lib/PublicInbox/LeiMirror.pm
@@ -16,6 +16,7 @@ use Carp qw(croak);
 use URI;
 use PublicInbox::Config;
 use PublicInbox::Inbox;
+use PublicInbox::Git;
 use PublicInbox::LeiCurl;
 use PublicInbox::OnDestroy;
 use PublicInbox::SHA qw(sha256_hex sha1_hex);
@@ -31,7 +32,7 @@ sub keep_going ($) {
                $_[0]->{lei}->{opt}->{'keep-going'});
 }
 
-sub _wq_done_wait { # awaitpid cb (via wq_eof / IPC->awaitpid_init)
+sub _wq_done_wait { # awaitpid cb (via wq_eof)
        my ($pid, $mrr, $lei) = @_;
        if ($?) {
                $lei->child_error($?);
@@ -258,7 +259,8 @@ sub run_reap {
 sub start_cmd {
        my ($self, $cmd, $opt, $fini) = @_;
        do_reap($self);
-       $self->{lei}->qerr("# @$cmd");
+       utf8::decode(my $msg = "# @$cmd");
+       $self->{lei}->qerr($msg);
        return if $self->{dry_run};
        $LIVE->{spawn($cmd, undef, $opt)} = [ \&reap_cmd, $self, $cmd, $fini ]
 }
@@ -275,6 +277,8 @@ sub fetch_args ($$) {
                        ($lei->{opt}->{jobs} // 1) > 1;
        push @cmd, '-v' if $lei->{opt}->{verbose};
        push(@cmd, '-p') if $lei->{opt}->{prune};
+       PublicInbox::Git::version() >= ((2 << 24) | (29 << 16)) and
+               push(@cmd, '--no-write-fetch-head');
        @cmd;
 }
 
@@ -284,6 +288,19 @@ sub upr { # feed `git update-ref --stdin -z' verbosely
        print $w "$op ", join("\0", @rest, '') or die "print(w): $!";
 }
 
+sub start_update_ref {
+       my ($fgrp) = @_;
+       pipe(my ($r, $w)) or die "pipe: $!";
+       my $cmd = [ 'git', "--git-dir=$fgrp->{cur_dst}",
+               qw(update-ref --stdin -z) ];
+       my $pack = PublicInbox::OnDestroy->new($$, \&satellite_done, $fgrp);
+       start_cmd($fgrp, $cmd, { 0 => $r, 2 => $fgrp->{lei}->{2} }, $pack);
+       close $r or die "close(r): $!";
+       $fgrp->{dry_run} ? undef : $w;
+}
+
+sub upref_warn { warn "E: close(update-ref --stdin): $! (need git 1.8.5+)\n" }
+
 sub fgrp_update {
        my ($fgrp) = @_;
        return if !keep_going($fgrp);
@@ -295,14 +312,9 @@ sub fgrp_update {
        close $srcfh;
        my %dst = map { chomp; split(/\0/) } (<$dstfh>);
        close $dstfh;
-       pipe(my ($r, $w)) or die "pipe: $!";
-       my $cmd = [ 'git', "--git-dir=$fgrp->{cur_dst}",
-               qw(update-ref --stdin -z) ];
+       my $w = start_update_ref($fgrp) or return;
        my $lei = $fgrp->{lei};
-       my $pack = PublicInbox::OnDestroy->new($$, \&satellite_done, $fgrp);
-       start_cmd($fgrp, $cmd, { 0 => $r, 2 => $lei->{2} }, $pack);
-       close $r or die "close(r): $!";
-       return if $fgrp->{dry_run};
+       my $ndel;
        for my $ref (keys %dst) {
                my $new = delete $src{$ref};
                my $old = $dst{$ref};
@@ -311,18 +323,33 @@ sub fgrp_update {
                                upr($lei, $w, 'update', $ref, $new, $old);
                } else {
                        upr($lei, $w, 'delete', $ref, $old);
+                       ++$ndel;
                }
        }
-       while (my ($ref, $oid) = each %src) {
-               upr($lei, $w, 'create', $ref, $oid);
+       # git's ref files backend doesn't allow directory/file conflicts
+       # between `delete' and `create' ops:
+       if ($ndel && scalar(keys %src)) {
+               $fgrp->{-create_refs} = \%src;
+       } else {
+               while (my ($ref, $oid) = each %src) {
+                       upr($lei, $w, 'create', $ref, $oid);
+               }
        }
-       close($w) or warn "E: close(update-ref --stdin): $! (need git 1.8.5+)\n";
+       close($w) or upref_warn();
 }
 
 sub satellite_done {
        my ($fgrp) = @_;
-       pack_refs($fgrp, $fgrp->{cur_dst});
-       run_puh($fgrp);
+       if (my $create = delete $fgrp->{-create_refs}) {
+               my $w = start_update_ref($fgrp) or return;
+               while (my ($ref, $oid) = each %$create) {
+                       upr($fgrp->{lei}, $w, 'create', $ref, $oid);
+               }
+               close($w) or upref_warn();
+       } else {
+               pack_refs($fgrp, $fgrp->{cur_dst});
+               run_puh($fgrp);
+       }
 }
 
 sub pack_refs {
@@ -504,12 +531,9 @@ sub resume_fetch {
        my $dst = $self->{cur_dst} // $self->{dst};
        my @git = ('git', "--git-dir=$dst");
        my $opt = { 2 => $self->{lei}->{2} };
-       my $rn = 'origin'; # configurable?
+       my $rn = 'random'.int(rand(1 << 30));
        for ("url=$uri", "fetch=+refs/*:refs/*", 'mirror=true') {
-               my @kv = split(/=/, $_, 2);
-               $kv[0] = "remote.$rn.$kv[0]";
-               next if $self->{dry_run};
-               run_die([@git, 'config', @kv], undef, $opt);
+               push @git, '-c', "remote.$rn.$_";
        }
        my $cmd = [ @{$self->{-torsocks}}, @git,
                        fetch_args($self->{lei}, $opt), $rn ];