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| | # Copyright (C) 2016-2021 all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
# a tied handle for auto reaping of children tied to a pipe, see perltie(1)
package PublicInbox::ProcessPipe;
use strict;
use v5.10.1;
use Carp qw(carp);
sub TIEHANDLE {
my ($class, $pid, $fh, $cb, $arg) = @_;
bless { pid => $pid, fh => $fh, ppid => $$, cb => $cb, arg => $arg },
$class;
}
sub BINMODE { binmode(shift->{fh}) } # for IO::Uncompress::Gunzip
sub READ { read($_[0]->{fh}, $_[1], $_[2], $_[3] || 0) }
sub READLINE { readline($_[0]->{fh}) }
sub WRITE {
use bytes qw(length);
syswrite($_[0]->{fh}, $_[1], $_[2] // length($_[1]), $_[3] // 0);
}
sub PRINT {
my $self = shift;
print { $self->{fh} } @_;
}
sub FILENO { fileno($_[0]->{fh}) }
sub _close ($;$) {
my ($self, $wait) = @_;
my $fh = delete $self->{fh};
my $ret = defined($fh) ? close($fh) : '';
my ($pid, $cb, $arg) = delete @$self{qw(pid cb arg)};
return $ret unless defined($pid) && $self->{ppid} == $$;
if ($wait) { # caller cares about the exit status:
my $wp = waitpid($pid, 0);
if ($wp == $pid) {
$ret = '' if $?;
if ($cb) {
eval { $cb->($arg, $pid) };
carp "E: cb(arg, $pid): $@" if $@;
}
} else {
carp "waitpid($pid, 0) = $wp, \$!=$!, \$?=$?";
}
} else { # caller just undef-ed it, let event loop deal with it
require PublicInbox::DS;
PublicInbox::DS::dwaitpid($pid, $cb, $arg);
}
$ret;
}
# if caller uses close(), assume they want to check $? immediately so
# we'll waitpid() synchronously. n.b. wantarray doesn't seem to
# propagate `undef' down to tied methods, otherwise I'd rely on that.
sub CLOSE { _close($_[0], 1) }
# if relying on DESTROY, assume the caller doesn't care about $? and
# we can let the event loop call waitpid() whenever it gets SIGCHLD
sub DESTROY {
_close($_[0]);
undef;
}
1;
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