+# Copyright (C) 2016 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+package PublicInbox::Spamcheck::Spamc;
+use strict;
+use warnings;
+use PublicInbox::Spawn qw(popen_rd spawn);
+use IO::File;
+use Fcntl qw(:DEFAULT SEEK_SET);
+
+sub new {
+ my ($class) = @_;
+ bless {
+ checkcmd => [qw(spamc -E --headers)],
+ hamcmd => [qw(spamc -L ham)],
+ spamcmd => [qw(spamc -L spam)],
+ }, $class;
+}
+
+sub spamcheck {
+ my ($self, $msg, $out) = @_;
+
+ my $tmp;
+ my $fd = _msg_to_fd($self, $msg, \$tmp);
+ my $rdr = { 0 => $fd };
+ my ($fh, $pid) = popen_rd($self->{checkcmd}, undef, $rdr);
+ defined $pid or die "failed to popen_rd spamc: $!\n";
+ my $r;
+ unless (ref $out) {
+ my $buf = '';
+ $out = \$buf;
+ }
+ do {
+ $r = sysread($fh, $$out, 65536, length($$out));
+ } while (defined($r) && $r != 0);
+ defined $r or die "read failed: $!";
+ close $fh or die "close failed: $!";
+ waitpid($pid, 0);
+ ($? || $$out eq '') ? 0 : 1;
+}
+
+sub hamlearn {
+ my ($self, $msg, $rdr) = @_;
+ _learn($self, $msg, $rdr, 'hamcmd');
+}
+
+sub spamlearn {
+ my ($self, $msg, $rdr) = @_;
+ _learn($self, $msg, $rdr, 'spamcmd');
+}
+
+sub _learn {
+ my ($self, $msg, $rdr, $field) = @_;
+ $rdr ||= {};
+ $rdr->{1} ||= $self->_devnull;
+ $rdr->{2} ||= $self->_devnull;
+ my $tmp;
+ $rdr->{0} = _msg_to_fd($self, $msg, \$tmp);
+ my $pid = spawn($self->{$field}, undef, $rdr);
+ waitpid($pid, 0);
+ !$?;
+}
+
+sub _devnull {
+ my ($self) = @_;
+ my $fd = $self->{-devnullfd};
+ return $fd if defined $fd;
+ open my $fh, '+>', '/dev/null' or
+ die "failed to open /dev/null: $!";
+ $self->{-devnull} = $fh;
+ $self->{-devnullfd} = fileno($fh);
+}
+
+sub _msg_to_fd {
+ my ($self, $msg, $tmpref) = @_;
+ my $tmpfh;
+ my $fd;
+ if (my $ref = ref($msg)) {
+
+ return $msg->fileno if $ref ne 'SCALAR' && $msg->can('fileno');
+
+ $tmpfh = IO::File->new_tmpfile;
+ $tmpfh->autoflush(1);
+ $msg = \($msg->as_string) if $ref ne 'SCALAR';
+ print $tmpfh $$msg or die "failed to print: $!";
+ sysseek($tmpfh, 0, SEEK_SET) or
+ die "sysseek(fh) failed: $!";
+ $$tmpref = $tmpfh;
+
+ return fileno($tmpfh);
+ }
+ $msg;
+}
+
+1;