From: Eric Wong <e@80x24.org>
To: meta@public-inbox.org
Subject: [PATCH] dir_idle: detect files which are gone
Date: Fri, 14 May 2021 07:27:57 +0000 [thread overview]
Message-ID: <20210514072757.24883-1-e@80x24.org> (raw)
lei now makes use of this to clean up after unlinked sockets
with less delay. This will also be used to maintain
mail_sync.sqlite3.
---
lib/PublicInbox/DirIdle.pm | 11 ++++--
lib/PublicInbox/FakeInotify.pm | 63 +++++++++++++++++++++++++++++-----
lib/PublicInbox/KQNotify.pm | 12 ++++---
lib/PublicInbox/LEI.pm | 17 +++++----
t/dir_idle.t | 18 +++++++++-
t/fake_inotify.t | 21 +++++++++---
6 files changed, 115 insertions(+), 27 deletions(-)
diff --git a/lib/PublicInbox/DirIdle.pm b/lib/PublicInbox/DirIdle.pm
index 5437190d..e53fd9d1 100644
--- a/lib/PublicInbox/DirIdle.pm
+++ b/lib/PublicInbox/DirIdle.pm
@@ -8,22 +8,25 @@ use parent 'PublicInbox::DS';
use PublicInbox::Syscall qw(EPOLLIN EPOLLET);
use PublicInbox::In2Tie;
-my ($MAIL_IN, $ino_cls);
+my ($MAIL_IN, $MAIL_GONE, $ino_cls);
if ($^O eq 'linux' && eval { require Linux::Inotify2; 1 }) {
$MAIL_IN = Linux::Inotify2::IN_MOVED_TO() |
Linux::Inotify2::IN_CREATE();
+ $MAIL_GONE = Linux::Inotify2::IN_DELETE();
$ino_cls = 'Linux::Inotify2';
# Perl 5.22+ is needed for fileno(DIRHANDLE) support:
} elsif ($^V ge v5.22 && eval { require PublicInbox::KQNotify }) {
$MAIL_IN = PublicInbox::KQNotify::MOVED_TO_OR_CREATE();
+ $MAIL_GONE = PublicInbox::KQNotify::NOTE_DELETE();
$ino_cls = 'PublicInbox::KQNotify';
} else {
require PublicInbox::FakeInotify;
$MAIL_IN = PublicInbox::FakeInotify::MOVED_TO_OR_CREATE();
+ $MAIL_GONE = PublicInbox::FakeInotify::IN_DELETE();
}
sub new {
- my ($class, $dirs, $cb) = @_;
+ my ($class, $dirs, $cb, $gone) = @_;
my $self = bless { cb => $cb }, $class;
my $inot;
if ($ino_cls) {
@@ -36,7 +39,9 @@ sub new {
}
# Linux::Inotify2->watch or similar
- $inot->watch($_, $MAIL_IN) for @$dirs;
+ my $fl = $MAIL_IN;
+ $fl |= $MAIL_GONE if $gone;
+ $inot->watch($_, $fl) for @$dirs;
$self->{inot} = $inot;
PublicInbox::FakeInotify::poll_once($self) if !$ino_cls;
$self;
diff --git a/lib/PublicInbox/FakeInotify.pm b/lib/PublicInbox/FakeInotify.pm
index 25818e07..644f5b5b 100644
--- a/lib/PublicInbox/FakeInotify.pm
+++ b/lib/PublicInbox/FakeInotify.pm
@@ -5,16 +5,29 @@
# enough of Linux::Inotify2
package PublicInbox::FakeInotify;
use strict;
+use v5.10.1;
+use parent qw(Exporter);
use Time::HiRes qw(stat);
use PublicInbox::DS qw(add_timer);
sub IN_MODIFY () { 0x02 } # match Linux inotify
# my $IN_MOVED_TO = 0x80;
# my $IN_CREATE = 0x100;
sub MOVED_TO_OR_CREATE () { 0x80 | 0x100 }
+sub IN_DELETE () { 0x00000200 }
+
+our @EXPORT_OK = qw(fill_dirlist on_dir_change);
my $poll_intvl = 2; # same as Filesys::Notify::Simple
-sub new { bless { watch => {} }, __PACKAGE__ }
+sub new { bless { watch => {}, dirlist => {} }, __PACKAGE__ }
+
+sub fill_dirlist ($$$) {
+ my ($self, $path, $dh) = @_;
+ my $dirlist = $self->{dirlist}->{$path} = {};
+ while (defined(my $n = readdir($dh))) {
+ $dirlist->{$n} = undef if $n !~ /\A\.\.?\z/;
+ }
+}
# behaves like Linux::Inotify2->watch
sub watch {
@@ -22,11 +35,19 @@ sub watch {
my @st = stat($path) or return;
my $k = "$path\0$mask";
$self->{watch}->{$k} = $st[10]; # 10 - ctime
+ if ($mask & IN_DELETE) {
+ opendir(my $dh, $path) or return;
+ fill_dirlist($self, $path, $dh);
+ }
bless [ $self->{watch}, $k ], 'PublicInbox::FakeInotify::Watch';
}
-sub on_new_files ($$$$) {
- my ($events, $dh, $path, $old_ctime) = @_;
+# also used by KQNotify since it kevent requires readdir on st_nlink
+# count changes.
+sub on_dir_change ($$$$;$) {
+ my ($events, $dh, $path, $old_ctime, $dirlist) = @_;
+ my $oldlist = $dirlist->{$path};
+ my $newlist = $oldlist ? {} : undef;
while (defined(my $base = readdir($dh))) {
next if $base =~ /\A\.\.?\z/;
my $full = "$path/$base";
@@ -35,7 +56,19 @@ sub on_new_files ($$$$) {
push @$events,
bless(\$full, 'PublicInbox::FakeInotify::Event')
}
+ if (!@st) {
+ # ignore ENOENT due to race
+ warn "unhandled stat($full) error: $!\n" if !$!{ENOENT};
+ } elsif ($newlist) {
+ $newlist->{$base} = undef;
+ }
}
+ return if !$newlist;
+ delete @$oldlist{keys %$newlist};
+ $dirlist->{$path} = $newlist;
+ push(@$events, map {
+ bless \"$path/$_", 'PublicInbox::FakeInotify::GoneEvent'
+ } keys %$oldlist);
}
# behaves like non-blocking Linux::Inotify2->read
@@ -43,6 +76,7 @@ sub read {
my ($self) = @_;
my $watch = $self->{watch} or return ();
my $events = [];
+ my @watch_gone;
for my $x (keys %$watch) {
my ($path, $mask) = split(/\0/, $x, 2);
my @now = stat($path) or next;
@@ -52,14 +86,18 @@ sub read {
if ($mask & IN_MODIFY) {
push @$events,
bless(\$path, 'PublicInbox::FakeInotify::Event')
- } elsif ($mask & MOVED_TO_OR_CREATE) {
- opendir(my $dh, $path) or do {
+ } elsif ($mask & (MOVED_TO_OR_CREATE | IN_DELETE)) {
+ if (opendir(my $dh, $path)) {
+ on_dir_change($events, $dh, $path, $old_ctime,
+ $self->{dirlist});
+ } elsif ($!{ENOENT}) {
+ push @watch_gone, $x;
+ } else {
warn "W: opendir $path: $!\n";
- next;
- };
- on_new_files($events, $dh, $path, $old_ctime);
+ }
}
}
+ delete @$watch{@watch_gone};
@$events;
}
@@ -86,4 +124,13 @@ package PublicInbox::FakeInotify::Event;
use strict;
sub fullname { ${$_[0]} }
+
+sub IN_DELETE { 0 }
+
+package PublicInbox::FakeInotify::GoneEvent;
+use strict;
+our @ISA = qw(PublicInbox::FakeInotify::Event);
+
+sub IN_DELETE { 1 }
+
1;
diff --git a/lib/PublicInbox/KQNotify.pm b/lib/PublicInbox/KQNotify.pm
index cfea6b1b..fc321a16 100644
--- a/lib/PublicInbox/KQNotify.pm
+++ b/lib/PublicInbox/KQNotify.pm
@@ -5,9 +5,10 @@
# using IO::KQueue on *BSD systems.
package PublicInbox::KQNotify;
use strict;
+use v5.10.1;
use IO::KQueue;
use PublicInbox::DSKQXS; # wraps IO::KQueue for fork-safe DESTROY
-use PublicInbox::FakeInotify;
+use PublicInbox::FakeInotify qw(fill_dirlist on_dir_change);
use Time::HiRes qw(stat);
# NOTE_EXTEND detects rename(2), NOTE_WRITE detects link(2)
@@ -37,8 +38,9 @@ sub watch {
EV_ADD | EV_CLEAR, # flags
$mask, # fflags
0, 0); # data, udata
- if ($mask == NOTE_WRITE || $mask == MOVED_TO_OR_CREATE) {
+ if ($mask & (MOVED_TO_OR_CREATE | NOTE_DELETE)) {
$self->{watch}->{$ident} = $watch;
+ fill_dirlist($self, $path, $fh) if $mask & NOTE_DELETE;
} else {
die "TODO Not implemented: $mask";
}
@@ -68,12 +70,12 @@ sub read {
if (!defined($old_ctime)) {
push @$events,
bless(\$path, 'PublicInbox::FakeInotify::Event')
- } elsif ($mask & MOVED_TO_OR_CREATE) {
+ } elsif ($mask & (MOVED_TO_OR_CREATE | NOTE_DELETE)) {
my @new_st = stat($path) or next;
$self->{watch}->{$ident}->[3] = $new_st[10]; # ctime
rewinddir($dh);
- PublicInbox::FakeInotify::on_new_files($events, $dh,
- $path, $old_ctime);
+ on_dir_change($events, $dh, $path, $old_ctime,
+ $self->{dirlist});
}
}
@$events;
diff --git a/lib/PublicInbox/LEI.pm b/lib/PublicInbox/LEI.pm
index 7349c261..5f178418 100644
--- a/lib/PublicInbox/LEI.pm
+++ b/lib/PublicInbox/LEI.pm
@@ -28,7 +28,7 @@ use Time::HiRes qw(stat); # ctime comparisons for config cache
use File::Path qw(mkpath);
use File::Spec;
our $quit = \&CORE::exit;
-our ($current_lei, $errors_log, $listener, $oldset);
+our ($current_lei, $errors_log, $listener, $oldset, $dir_idle);
my ($recv_cmd, $send_cmd);
my $GLP = Getopt::Long::Parser->new;
$GLP->configure(qw(gnu_getopt no_ignore_case auto_abbrev));
@@ -539,6 +539,7 @@ sub _lei_atfork_child {
}
close $listener if $listener;
undef $listener;
+ undef $dir_idle;
%PATH2CFG = ();
undef $errors_log;
$quit = \&CORE::exit;
@@ -1114,8 +1115,8 @@ sub dump_and_clear_log {
sub lazy_start {
my ($path, $errno, $narg) = @_;
local ($errors_log, $listener);
- ($errors_log) = ($path =~ m!\A(.+?/)[^/]+\z!);
- $errors_log .= 'errors.log';
+ my ($sock_dir) = ($path =~ m!\A(.+?)/[^/]+\z!);
+ $errors_log = "$sock_dir/errors.log";
my $addr = pack_sockaddr_un($path);
my $lk = bless { lock_path => $errors_log }, 'PublicInbox::Lock';
$lk->lock_acquire;
@@ -1187,9 +1188,13 @@ sub lazy_start {
local @SIG{keys %$sig} = values(%$sig) unless $sigfd;
undef $sig;
local $SIG{PIPE} = 'IGNORE';
- if ($sigfd) { # TODO: use inotify/kqueue to detect unlinked sockets
- undef $sigfd;
- PublicInbox::DS->SetLoopTimeout(5000);
+ require PublicInbox::DirIdle;
+ local $dir_idle = PublicInbox::DirIdle->new([$sock_dir], sub {
+ # just rely on wakeup ot hit PostLoopCallback set below
+ _dir_idle_handler(@_) if $_[0]->fullname ne $path;
+ }, 1);
+ if ($sigfd) {
+ undef $sigfd; # unref, already in DS::DescriptorMap
} else {
# wake up every second to accept signals if we don't
# have signalfd or IO::KQueue:
diff --git a/t/dir_idle.t b/t/dir_idle.t
index d62eb5a2..969c16e9 100644
--- a/t/dir_idle.t
+++ b/t/dir_idle.t
@@ -1,6 +1,22 @@
#!perl -w
# Copyright (C) 2020-2021 all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
-use Test::More;
+use v5.10.1; use strict; use PublicInbox::TestCommon;
+use PublicInbox::DS qw(now);
+use File::Path qw(make_path);
use_ok 'PublicInbox::DirIdle';
+my ($tmpdir, $for_destroy) = tmpdir();
+make_path("$tmpdir/a/b");
+my @x;
+my $cb = sub { push @x, \@_ };
+my $di = PublicInbox::DirIdle->new(["$tmpdir/a"], $cb, 1);
+PublicInbox::DS->SetLoopTimeout(1000);
+my $end = 3 + now;
+PublicInbox::DS->SetPostLoopCallback(sub { scalar(@x) == 0 && now < $end });
+tick(0.011);
+rmdir("$tmpdir/a/b") or xbail "rmdir $!";
+PublicInbox::DS->EventLoop;
+is(scalar(@x), 1, 'got an event') and
+ is($x[0]->[0]->fullname, "$tmpdir/a/b", 'got expected fullname');
+PublicInbox::DS->Reset;
done_testing;
diff --git a/t/fake_inotify.t b/t/fake_inotify.t
index 5c925ae6..734ddbfb 100644
--- a/t/fake_inotify.t
+++ b/t/fake_inotify.t
@@ -5,12 +5,12 @@
# Ensure FakeInotify can pick up rename(2) and link(2) operations
# used by Maildir writing tools
use strict;
-use Test::More;
use PublicInbox::TestCommon;
use_ok 'PublicInbox::FakeInotify';
my $MIN_FS_TICK = 0.011; # for low-res CONFIG_HZ=100 systems
my ($tmpdir, $for_destroy) = tmpdir();
mkdir "$tmpdir/new" or BAIL_OUT "mkdir: $!";
+mkdir "$tmpdir/new/rmd" or BAIL_OUT "mkdir: $!";
open my $fh, '>', "$tmpdir/tst" or BAIL_OUT "open: $!";
close $fh or BAIL_OUT "close: $!";
@@ -18,12 +18,12 @@ my $fi = PublicInbox::FakeInotify->new;
my $mask = PublicInbox::FakeInotify::MOVED_TO_OR_CREATE();
my $w = $fi->watch("$tmpdir/new", $mask);
-select undef, undef, undef, $MIN_FS_TICK;
+tick $MIN_FS_TICK;
rename("$tmpdir/tst", "$tmpdir/new/tst") or BAIL_OUT "rename: $!";
my @events = map { $_->fullname } $fi->read;
is_deeply(\@events, ["$tmpdir/new/tst"], 'rename(2) detected');
-select undef, undef, undef, $MIN_FS_TICK;
+tick $MIN_FS_TICK;
open $fh, '>', "$tmpdir/tst" or BAIL_OUT "open: $!";
close $fh or BAIL_OUT "close: $!";
link("$tmpdir/tst", "$tmpdir/new/link") or BAIL_OUT "link: $!";
@@ -31,10 +31,23 @@ link("$tmpdir/tst", "$tmpdir/new/link") or BAIL_OUT "link: $!";
is_deeply(\@events, ["$tmpdir/new/link"], 'link(2) detected');
$w->cancel;
-select undef, undef, undef, $MIN_FS_TICK;
+tick $MIN_FS_TICK;
link("$tmpdir/new/tst", "$tmpdir/new/link2") or BAIL_OUT "link: $!";
@events = map { $_->fullname } $fi->read;
is_deeply(\@events, [], 'link(2) not detected after cancel');
+$fi->watch("$tmpdir/new", PublicInbox::FakeInotify::IN_DELETE());
+
+tick $MIN_FS_TICK;
+rmdir("$tmpdir/new/rmd") or xbail "rmdir: $!";
+@events = $fi->read;
+is_deeply([map{ $_->fullname }@events], ["$tmpdir/new/rmd"], 'rmdir detected');
+ok($events[0]->IN_DELETE, 'IN_DELETE set on rmdir');
+
+tick $MIN_FS_TICK;
+unlink("$tmpdir/new/tst") or xbail "unlink: $!";
+@events = grep { ref =~ /Gone/ } $fi->read;
+is_deeply([map{ $_->fullname }@events], ["$tmpdir/new/tst"], 'unlink detected');
+ok($events[0]->IN_DELETE, 'IN_DELETE set on unlink');
PublicInbox::DS->Reset;
reply other threads:[~2021-05-14 7:27 UTC|newest]
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