pure Perl inotify support

This is a step towards improving the out-of-the-box experience
in achieving notifications without XS, extra downloads, and .so
loading + runtime mmap overhead.

This also fixes loongarch support of all Linux syscalls due to
a bad regexp :x

All the reachable Linux architectures listed at
<https://portal.cfarm.net/machines/list/> should be supported.
At the moment, there appears to be no reachable sparc* Linux
machines available to cfarm users.

Fixes: b0e5093aa3572a86 (syscall: add support for riscv64, 2022-08-11)

1 files changed, 20 insertions, 0 deletions

diff --git a/lib/PublicInbox/In3Watch.pm b/lib/PublicInbox/In3Watch.pm
new file mode 100644
index 00000000..bdb91869
--- /dev/null
+++ b/lib/PublicInbox/In3Watch.pm
@@ -0,0 +1,20 @@
+# Copyright (C) all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+
+# duck-type compatible with Linux::Inotify2::Watch for pure Perl
+# PublicInbox::Inotify3 for our needs, only
+package PublicInbox::In3Watch;
+use v5.12;
+
+sub mask { $_[0]->[1] }
+sub name { $_[0]->[2] }
+
+sub cancel {
+        my ($self) = @_;
+        my ($wd, $in3) = @$self[0, 3];
+        $in3 or return 1; # already canceled
+        pop @$self;
+        $in3->rm_watch($wd);
+}
+
+1;