# Copyright (C) 2020-2021 all contributors # License: AGPL-3.0+ # 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 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 => {}, dirlist => {} }, __PACKAGE__ } sub fill_dirlist ($$$) { my ($self, $path, $dh) = @_; my $dirlist = $self->{dirlist}->{$path} = {}; while (defined(my $n = readdir($dh))) { $dirlist->{$n} = undef if $n !~ /\A\.\.?\z/; } } # behaves like Linux::Inotify2->watch sub watch { my ($self, $path, $mask) = @_; my @st = stat($path) or return; my $k = "$path\0$mask"; $self->{watch}->{$k} = $st[10]; # 10 - ctime if ($mask & IN_DELETE) { opendir(my $dh, $path) or return; fill_dirlist($self, $path, $dh); } bless [ $self->{watch}, $k ], 'PublicInbox::FakeInotify::Watch'; } # also used by KQNotify since it kevent requires readdir on st_nlink # count changes. sub on_dir_change ($$$$$) { 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/$base"; my @st = stat($full); if (@st && $st[10] > $old_ctime) { push @$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 %$oldlist); } # behaves like non-blocking Linux::Inotify2->read sub read { my ($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); 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 | 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: $!\n"; } } } delete @$watch{@watch_gone}; @$events; } sub poll_once { my ($obj) = @_; $obj->event_step; # PublicInbox::InboxIdle::event_step add_timer($poll_intvl, \&poll_once, $obj); } package PublicInbox::FakeInotify::Watch; use strict; sub cancel { my ($self) = @_; delete $self->[0]->{$self->[1]}; } sub name { my ($self) = @_; (split(/\0/, $self->[1], 2))[0]; } 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;