1 files changed, 49 insertions, 0 deletions
diff --git a/lib/PublicInbox/GitAsyncCat.pm b/lib/PublicInbox/GitAsyncCat.pm
new file mode 100644
index 00000000..f168169f
--- /dev/null
+++ b/lib/PublicInbox/GitAsyncCat.pm
@@ -0,0 +1,49 @@
+# Copyright (C) 2020 all contributors <meta@public-inbox.org>
+# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
+#
+# internal class used by PublicInbox::Git + Danga::Socket
+# This parses the output pipe of "git cat-file --batch"
+#
+# Note: this does NOT set the non-blocking flag, we expect `git cat-file'
+# to be a local process, and git won't start writing a blob until it's
+# fully read.  So minimize context switching and read as much as possible
+# and avoid holding a buffer in our heap any longer than it has to live.
+package PublicInbox::GitAsyncCat;
+use strict;
+use parent qw(PublicInbox::DS Exporter);
+use fields qw(git);
+use PublicInbox::Syscall qw(EPOLLIN EPOLLET);
+our @EXPORT = qw(git_async_msg);
+
+sub new {
+        my ($class, $git) = @_;
+        my $self = fields::new($class);
+        $git->batch_prepare;
+        $self->SUPER::new($git->{in}, EPOLLIN|EPOLLET);
+        $self->{git} = $git;
+        $self;
+}
+
+sub event_step {
+        my ($self) = @_;
+        my $git = $self->{git} or return; # ->close-ed
+        my $inflight = $git->{inflight};
+        if (@$inflight) {
+                $git->cat_async_step($inflight);
+                $self->requeue if @$inflight || length(${$git->{'--batch'}});
+        }
+}
+
+sub close {
+        my ($self) = @_;
+        delete $self->{git};
+        $self->SUPER::close; # PublicInbox::DS::close
+}
+
+sub git_async_msg ($$$$) {
+        my ($ibx, $smsg, $cb, $arg) = @_;
+        $ibx->git->cat_async($smsg->{blob}, $cb, $arg);
+        $ibx->{async_cat} //= new(__PACKAGE__, $ibx->{git});
+}
+
+1;