Factor out atomic file overwriting into its own function.

[remoteglot] / remoteglot.pl

diff --git a/remoteglot.pl b/remoteglot.pl
index 675ef5011ec20788b08a343b0596083b5c853366..fb74e6eab5c0d04c454b532ae047ed509fe2141c 100755 (executable)
--- a/remoteglot.pl
+++ b/remoteglot.pl
@@ -269,37 +269,42 @@ sub handle_pgn {
        if (!defined($pgn) || !$pgn->read_game()) {
                warn "Error in parsing PGN from $url\n";
        } else {
-               $pgn->quick_parse_game;
-               my $pos = Position->start_pos($pgn->white, $pgn->black);
-               my $moves = $pgn->moves;
-               my @uci_moves = ();
-               for my $move (@$moves) {
-                       my $uci_move;
-                       ($pos, $uci_move) = $pos->make_pretty_move($move);
-                       push @uci_moves, $uci_move;
-               }
-               $pos->{'history'} = \@uci_moves;
-               $pos->{'pretty_history'} = $moves;
-
-               # Sometimes, PGNs lose a move or two for a short while,
-               # or people push out new ones non-atomically. 
-               # Thus, if we PGN doesn't change names but becomes
-               # shorter, we mistrust it for a few seconds.
-               my $trust_pgn = 1;
-               if (defined($last_pgn_white) && defined($last_pgn_black) &&
-                   $last_pgn_white eq $pgn->white &&
-                   $last_pgn_black eq $pgn->black &&
-                   scalar(@uci_moves) < scalar(@last_pgn_uci_moves)) {
-                       if (++$pgn_hysteresis_counter < 3) {
-                               $trust_pgn = 0; 
+               eval {
+                       $pgn->quick_parse_game;
+                       my $pos = Position->start_pos($pgn->white, $pgn->black);
+                       my $moves = $pgn->moves;
+                       my @uci_moves = ();
+                       for my $move (@$moves) {
+                               my $uci_move;
+                               ($pos, $uci_move) = $pos->make_pretty_move($move);
+                               push @uci_moves, $uci_move;
                        }
-               }
-               if ($trust_pgn) {
-                       $last_pgn_white = $pgn->white;
-                       $last_pgn_black = $pgn->black;
-                       @last_pgn_uci_moves = @uci_moves;
-                       $pgn_hysteresis_counter = 0;
-                       handle_position($pos);
+                       $pos->{'history'} = \@uci_moves;
+                       $pos->{'pretty_history'} = $moves;
+
+                       # Sometimes, PGNs lose a move or two for a short while,
+                       # or people push out new ones non-atomically. 
+                       # Thus, if we PGN doesn't change names but becomes
+                       # shorter, we mistrust it for a few seconds.
+                       my $trust_pgn = 1;
+                       if (defined($last_pgn_white) && defined($last_pgn_black) &&
+                           $last_pgn_white eq $pgn->white &&
+                           $last_pgn_black eq $pgn->black &&
+                           scalar(@uci_moves) < scalar(@last_pgn_uci_moves)) {
+                               if (++$pgn_hysteresis_counter < 3) {
+                                       $trust_pgn = 0; 
+                               }
+                       }
+                       if ($trust_pgn) {
+                               $last_pgn_white = $pgn->white;
+                               $last_pgn_black = $pgn->black;
+                               @last_pgn_uci_moves = @uci_moves;
+                               $pgn_hysteresis_counter = 0;
+                               handle_position($pos);
+                       }
+               };
+               if ($@) {
+                       warn "Error in parsing moves from $url\n";
                }
        }
        
@@ -737,11 +742,18 @@ sub output_json {
        }
        $json->{'refutation_lines'} = \%refutation_lines;
 
-       open my $fh, ">", $remoteglotconf::json_output . ".tmp"
+       my $encoded = JSON::XS::encode_json($json);
+       atomic_set_contents($remoteglotconf::json_output, $encoded);
+}
+
+sub atomic_set_contents {
+       my ($filename, $contents) = @_;
+
+       open my $fh, ">", $filename . ".tmp"
                or return;
-       print $fh JSON::XS::encode_json($json);
+       print $fh $contents;
        close $fh;
-       rename($remoteglotconf::json_output . ".tmp", $remoteglotconf::json_output);
+       rename($filename . ".tmp", $filename);
 }
 
 sub uciprint {