v2writable: support reindexing Xapian

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

diff --git a/lib/PublicInbox/Msgmap.pm b/lib/PublicInbox/Msgmap.pm
index 78922d3693c9647e0b11c3dc7fc300ce1a985147..128330506b151d16afe7cbde83429a06820f4891 100644 (file)
--- a/lib/PublicInbox/Msgmap.pm
+++ b/lib/PublicInbox/Msgmap.pm
@@ -24,9 +24,8 @@ sub new {
        new_file($class, "$d/msgmap.sqlite3", $writable);
 }
 
-sub new_file {
-       my ($class, $f, $writable) = @_;
-
+sub dbh_new {
+       my ($f, $writable) = @_;
        my $dbh = DBI->connect("dbi:SQLite:dbname=$f",'','', {
                AutoCommit => 1,
                RaiseError => 1,
@@ -35,6 +34,13 @@ sub new_file {
                sqlite_use_immediate_transaction => 1,
        });
        $dbh->do('PRAGMA case_sensitive_like = ON');
+       $dbh;
+}
+
+sub new_file {
+       my ($class, $f, $writable) = @_;
+
+       my $dbh = dbh_new($f, $writable);
        my $self = bless { dbh => $dbh }, $class;
 
        if ($writable) {
@@ -49,12 +55,13 @@ sub new_file {
 # used to keep track of used numeric mappings for v2 reindex
 sub tmp_clone {
        my ($self) = @_;
-       my ($fh, $fn) = tempfile(EXLOCK => 0);
+       my ($fh, $fn) = tempfile('msgmap-XXXXXXXX', EXLOCK => 0, TMPDIR => 1);
        $self->{dbh}->sqlite_backup_to_file($fn);
        my $tmp = ref($self)->new_file($fn, 1);
        $tmp->{dbh}->do('PRAGMA synchronous = OFF');
        $tmp->{tmp_name} = $fn; # SQLite won't work if unlinked, apparently
-       $fh = undef;
+       $tmp->{pid} = $$;
+       close $fh or die "failed to close $fn: $!";
        $tmp;
 }
 
@@ -205,7 +212,28 @@ sub mid_set {
 sub DESTROY {
        my ($self) = @_;
        delete $self->{dbh};
-       unlink $self->{tmp_name} if defined $self->{tmp_name};
+       my $f = delete $self->{tmp_name};
+       if (defined $f && $self->{pid} == $$) {
+               unlink $f or warn "failed to unlink $f: $!\n";
+       }
+}
+
+sub atfork_parent {
+       my ($self) = @_;
+       my $f = $self->{tmp_name} or die "not a temporary clone\n";
+       delete $self->{dbh} and die "tmp_clone dbh not prepared for parent";
+       my $dbh = $self->{dbh} = dbh_new($f, 1);
+       $dbh->do('PRAGMA synchronous = OFF');
+}
+
+sub atfork_prepare {
+       my ($self) = @_;
+       my $f = $self->{tmp_name} or die "not a temporary clone\n";
+       $self->{pid} == $$ or
+               die "BUG: atfork_prepare not called from $self->{pid}\n";
+       $self->{dbh} or die "temporary clone not open\n";
+       # must clobber prepared statements
+       %$self = (tmp_name => $f, pid => $$);
 }
 
 1;