# Base class for per-inbox locking
package PublicInbox::Lock;
use strict;
-use warnings;
+use v5.10.1;
use Fcntl qw(:flock :DEFAULT);
use Carp qw(croak);
+use PublicInbox::OnDestroy;
+use File::Temp ();
# we only acquire the flock if creating or reindexing;
# PublicInbox::Import already has the lock on its own.
sub lock_acquire {
my ($self) = @_;
- croak 'already locked' if $self->{lockfh};
- my $lock_path = $self->{lock_path} or return;
+ my $lock_path = $self->{lock_path};
+ croak 'already locked '.($lock_path // '(undef)') if $self->{lockfh};
+ return unless defined($lock_path);
sysopen(my $lockfh, $lock_path, O_WRONLY|O_CREAT) or
- die "failed to open lock $lock_path: $!\n";
- flock($lockfh, LOCK_EX) or die "lock failed: $!\n";
+ croak "failed to open $lock_path: $!\n";
+ flock($lockfh, LOCK_EX) or croak "lock $lock_path failed: $!\n";
$self->{lockfh} = $lockfh;
}
sub lock_release {
+ my ($self, $wake) = @_;
+ defined(my $lock_path = $self->{lock_path}) or return;
+ my $lockfh = delete $self->{lockfh} or croak "not locked: $lock_path";
+
+ syswrite($lockfh, '.') if $wake;
+
+ flock($lockfh, LOCK_UN) or croak "unlock $lock_path failed: $!\n";
+ close $lockfh or croak "close $lock_path failed: $!\n";
+}
+
+# caller must use return value
+sub lock_for_scope {
my ($self) = @_;
- return unless $self->{lock_path};
- my $lockfh = delete $self->{lockfh} or croak 'not locked';
-
- # NetBSD 8.1 and OpenBSD 6.5 (and maybe other versions/*BSDs) lack
- # NOTE_CLOSE_WRITE from FreeBSD 11+, so trigger NOTE_WRITE, instead.
- # We also need to change the ctime on Linux systems w/o inotify
- if ($^O ne 'linux' || !eval { require Linux::Inotify2; 1 }) {
- syswrite($lockfh, '.');
- }
- flock($lockfh, LOCK_UN) or die "unlock failed: $!\n";
- close $lockfh or die "close failed: $!\n";
+ $self->lock_acquire;
+ PublicInbox::OnDestroy->new(\&lock_release, $self);
+}
+
+sub new_tmp {
+ my ($cls, $ident) = @_;
+ my $tmp = File::Temp->new("$ident.lock-XXXXXX", TMPDIR => 1);
+ bless { lock_path => $tmp->filename, tmp => $tmp }, $cls;
}
1;