watch: use signalfd for Maildir watching

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

diff --git a/lib/PublicInbox/WatchMaildir.pm b/lib/PublicInbox/WatchMaildir.pm
index 22f190366a4696f7ead6cb9ffa2b2346d0001ca9..4d3cd032e5a5664fb5f41fee42cd68194655fc97 100644 (file)
--- a/lib/PublicInbox/WatchMaildir.pm
+++ b/lib/PublicInbox/WatchMaildir.pm
@@ -8,9 +8,9 @@ use strict;
 use warnings;
 use PublicInbox::Eml;
 use PublicInbox::InboxWritable;
-use File::Temp 0.19 (); # 0.19 for ->newdir
 use PublicInbox::Filter::Base qw(REJECT);
 use PublicInbox::Spamcheck;
+use PublicInbox::Sigfd;
 use PublicInbox::DS qw(now);
 use POSIX qw(_exit WNOHANG);
 *mime_from_path = \&PublicInbox::InboxWritable::mime_from_path;
@@ -108,6 +108,7 @@ sub new {
                imap => scalar keys %imap ? \%imap : undef,
                importers => {},
                opendirs => {}, # dirname => dirhandle (in progress scans)
+               ops => [], # 'quit', 'full'
        }, $class;
 }
 
@@ -195,7 +196,9 @@ sub _try_path {
 
 sub quit {
        my ($self) = @_;
-       trigger_scan($self, 'quit') or $self->{quit} = 1;
+       $self->{quit} = 1;
+       %{$self->{opendirs}} = ();
+       _done_for_now($self);
        if (my $imap_pid = $self->{-imap_pid}) {
                kill('QUIT', $imap_pid);
        }
@@ -213,24 +216,15 @@ sub quit {
 sub watch_fs {
        my ($self) = @_;
        require PublicInbox::DirIdle;
-       my $scan = File::Temp->newdir("public-inbox-watch.$$.scan.XXXXXX",
-                                       TMPDIR => 1);
-       my $scandir = $self->{scandir} = $scan->dirname;
-       my $scan_re = qr!\A$scandir/!;
        my $done = sub {
                delete $self->{done_timer};
                _done_for_now($self);
        };
        my $cb = sub {
-               my $path = $_[0]->fullname;
-               if ($path =~ $scan_re) {
-                       scan($self, $path);
-               } else {
-                       _try_path($self, $path);
-               }
+               _try_path($self, $_[0]->fullname);
                $self->{done_timer} //= PublicInbox::DS::requeue($done);
        };
-       my $di = PublicInbox::DirIdle->new([@{$self->{mdir}}, $scandir], $cb);
+       my $di = PublicInbox::DirIdle->new($self->{mdir}, $cb);
        PublicInbox::DS->SetPostLoopCallback(sub { !$self->{quit} });
        PublicInbox::DS->EventLoop;
        _done_for_now($self);
@@ -485,6 +479,12 @@ sub watch_imap_idle_1 ($$$) {
        }
 }
 
+sub watch_atfork_child ($) {
+       my ($self) = @_;
+       PublicInbox::Sigfd::sig_setmask($self->{oldset});
+       %SIG = (%SIG, %{$self->{sig}});
+}
+
 sub watch_imap_idle_all ($$) {
        my ($self, $idle) = @_; # $idle = [[ uri1, intvl1 ], [ uri2, intvl2 ]]
        $self->{mics} = {}; # going to be forking, so disconnect
@@ -494,6 +494,7 @@ sub watch_imap_idle_all ($$) {
                        my ($uri, $intvl) = @$uri_intvl;
                        defined(my $pid = fork) or die "fork: $!";
                        if ($pid == 0) {
+                               watch_atfork_child($self);
                                delete $self->{idle_pids};
                                watch_imap_idle_1($self, $uri, $intvl);
                                _exit(0);
@@ -564,15 +565,20 @@ sub watch_imap ($) {
 }
 
 sub watch {
-       my ($self) = @_;
+       my ($self, $sig, $oldset) = @_;
+       $self->{oldset} = $oldset;
+       $self->{sig} = $sig;
        if ($self->{mdre} && $self->{imap}) {
                defined(my $pid = fork) or die "fork: $!";
                if ($pid == 0) {
+                       watch_atfork_child($self);
                        imap_start($self);
                        goto &watch_imap;
                }
                $self->{-imap_pid} = $pid;
        } elsif ($self->{imap}) {
+               # not a child process, but no signalfd, yet:
+               watch_atfork_child($self);
                imap_start($self);
                goto &watch_imap;
        }
@@ -580,23 +586,18 @@ sub watch {
 }
 
 sub trigger_scan {
-       my ($self, $base) = @_;
-       my $dir = $self->{scandir} or return;
-       open my $fh, '>', "$dir/$base" or die "open $dir/$base failed: $!\n";
-       close $fh or die "close $dir/$base failed: $!\n";
+       my ($self, $op) = @_;
+       push @{$self->{ops}}, $op;
+       PublicInbox::DS::requeue($self);
 }
 
-sub scan {
-       my ($self, $path) = @_;
-       if ($path =~ /quit\z/) {
-               %{$self->{opendirs}} = ();
-               _done_for_now($self);
-               delete $self->{scandir};
-               $self->{quit} = 1;
-               return;
-       }
-       # else: $path =~ /(cont|full)\z/
+# called directly, and by PublicInbox::DS
+sub event_step ($) {
+       my ($self) = @_;
        return if $self->{quit};
+       my $op = shift @{$self->{ops}};
+
+       # continue existing scan
        my $max = 10;
        my $opendirs = $self->{opendirs};
        my @dirnames = keys %$opendirs;
@@ -609,7 +610,7 @@ sub scan {
                }
                $opendirs->{$dir} = $dh if $n < 0;
        }
-       if ($path =~ /full\z/) {
+       if ($op && $op eq 'full') {
                foreach my $dir (@{$self->{mdir}}) {
                        next if $opendirs->{$dir}; # already in progress
                        my $ok = opendir(my $dh, $dir);
@@ -627,7 +628,13 @@ sub scan {
        }
        _done_for_now($self);
        # do we have more work to do?
-       trigger_scan($self, 'cont') if keys %$opendirs;
+       PublicInbox::DS::requeue($self) if keys %$opendirs;
+}
+
+sub scan {
+       my ($self, $op) = @_;
+       push @{$self->{ops}}, $op;
+       goto &event_step;
 }
 
 sub _importer_for {