X-Git-Url: http://www.git.stargrave.org/?a=blobdiff_plain;f=lib%2FPublicInbox%2FFakeInotify.pm;h=6d2696019d8324fc3676d4e49efb783e10efc15a;hb=ef45dcc37abfdf467597f912ec290c4d39218ef6;hp=9275861368a0a00df5b95ff8acb4776413568d34;hpb=1bc3707e3e0983c9aed898980ec8acf6501813f7;p=public-inbox.git

diff --git a/lib/PublicInbox/FakeInotify.pm b/lib/PublicInbox/FakeInotify.pm
index 92758613..6d269601 100644
--- a/lib/PublicInbox/FakeInotify.pm
+++ b/lib/PublicInbox/FakeInotify.pm
@@ -1,20 +1,36 @@
-# Copyright (C) 2020 all contributors <meta@public-inbox.org>
+# Copyright (C) 2020-2021 all contributors <meta@public-inbox.org>
 # License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
 
 # for systems lacking Linux::Inotify2 or IO::KQueue, just emulates
 # 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;
+use PublicInbox::DS qw(add_timer);
 sub IN_MODIFY () { 0x02 } # match Linux inotify
+# my $IN_MOVED_FROM	 0x00000040	/* File was moved from X.  */
 # my $IN_MOVED_TO = 0x80;
 # my $IN_CREATE = 0x100;
 sub MOVED_TO_OR_CREATE () { 0x80 | 0x100 }
+sub IN_DELETE () { 0x200 }
+sub IN_DELETE_SELF () { 0x400 }
+sub IN_MOVE_SELF () { 0x800 }
+
+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 +38,19 @@ 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 ($$$$) {
-	my ($events, $dh, $path, $old_ctime) = @_;
+# also used by KQNotify since it kevent requires readdir on st_nlink
+# count changes.
+sub on_dir_change ($$$$$) {
+	my ($events, $dh, $path, $old_ctime, $dirlist) = @_;
+	my $oldlist = $dirlist->{$path};
+	my $newlist = $oldlist ? {} : undef;
 	while (defined(my $base = readdir($dh))) {
 		next if $base =~ /\A\.\.?\z/;
 		my $full = "$path/$base";
@@ -35,7 +59,19 @@ sub on_new_files ($$$$) {
 			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
@@ -43,30 +79,43 @@ 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;
+		my @now = stat($path);
+		if (!@now && $!{ENOENT} && ($mask & IN_DELETE_SELF)) {
+			push @$events, bless(\$path,
+				'PublicInbox::FakeInotify::SelfGoneEvent');
+			push @watch_gone, $x;
+			delete $self->{dirlist}->{$path};
+		}
+		next if !@now;
 		my $old_ctime = $watch->{$x};
 		$watch->{$x} = $now[10];
 		next if $old_ctime == $now[10];
 		if ($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;
+				delete $self->{dirlist}->{$path};
+			} else {
 				warn "W: opendir $path: $!\n";
-				next;
-			};
-			on_new_files($events, $dh, $path, $old_ctime);
+			}
 		}
 	}
+	delete @$watch{@watch_gone};
 	@$events;
 }
 
 sub poll_once {
 	my ($obj) = @_;
 	$obj->event_step; # PublicInbox::InboxIdle::event_step
-	PublicInbox::DS::add_timer($poll_intvl, \&poll_once, $obj);
+	add_timer($poll_intvl, \&poll_once, $obj);
 }
 
 package PublicInbox::FakeInotify::Watch;
@@ -86,4 +135,22 @@ package PublicInbox::FakeInotify::Event;
 use strict;
 
 sub fullname { ${$_[0]} }
+
+sub IN_DELETE { 0 }
+sub IN_MOVED_FROM { 0 }
+sub IN_DELETE_SELF { 0 }
+
+package PublicInbox::FakeInotify::GoneEvent;
+use strict;
+our @ISA = qw(PublicInbox::FakeInotify::Event);
+
+sub IN_DELETE { 1 }
+sub IN_MOVED_FROM { 0 }
+
+package PublicInbox::FakeInotify::SelfGoneEvent;
+use strict;
+our @ISA = qw(PublicInbox::FakeInotify::GoneEvent);
+
+sub IN_DELETE_SELF { 1 }
+
 1;