3 files changed, 30 insertions, 22 deletions

diff --git a/lib/PublicInbox/Daemon.pm b/lib/PublicInbox/Daemon.pm
index 1520f8f2..155707e1 100644
--- a/lib/PublicInbox/Daemon.pm
+++ b/lib/PublicInbox/Daemon.pm
@@ -654,14 +654,8 @@ sub run ($$$;$) {
         my $af_default = $default =~ /:8080\z/ ? 'httpready' : undef;
         my $for_destroy = daemonize();
 
-        # this wastes a bit of memory for non-PublicInbox::WWW -httpd users
-        # oh well...
-        eval {
-                require PublicInbox::Gcf2;
-                require PublicInbox::Gcf2Client;
-        };
-        local $PublicInbox::GitAsyncCat::GCF2C =
-                                PublicInbox::Gcf2Client::new() if !$@;
+        # localize GCF2C for tests:
+        local $PublicInbox::GitAsyncCat::GCF2C;
 
         daemon_loop($refresh, $post_accept, $tlsd, $af_default);
         PublicInbox::DS->Reset;
diff --git a/lib/PublicInbox/Gcf2Client.pm b/lib/PublicInbox/Gcf2Client.pm
index 42ff1bf3..ab486de5 100644
--- a/lib/PublicInbox/Gcf2Client.pm
+++ b/lib/PublicInbox/Gcf2Client.pm
@@ -8,27 +8,28 @@ use parent qw(PublicInbox::DS);
 use PublicInbox::Git;
 use PublicInbox::Spawn qw(popen_rd);
 use IO::Handle ();
-use PublicInbox::Syscall qw(EPOLLONESHOT EPOLLOUT);
+use PublicInbox::Syscall qw(EPOLLONESHOT);
 # fields:
 #        async_cat => GitAsyncCat ref (read-only pipe)
 #        sock => writable pipe to Gcf2::loop
 
-sub new { bless($_[0] // {}, __PACKAGE__) }
 
-sub gcf2c_begin ($) {
-        my ($self) = @_;
+sub new  {
+        my ($rdr) = @_;
+        my $self = bless {}, __PACKAGE__;
         # ensure the child process has the same @INC we do:
         my $env = { PERL5LIB => join(':', @INC) };
         my ($out_r, $out_w);
         pipe($out_r, $out_w) or die "pipe failed: $!";
-        my $rdr = { 0 => $out_r, 2 => $self->{2} };
+        $rdr //= {};
+        $rdr->{0} = $out_r;
         my $cmd = [$^X, qw[-MPublicInbox::Gcf2 -e PublicInbox::Gcf2::loop()]];
         @$self{qw(in pid)} = popen_rd($cmd, $env, $rdr);
         fcntl($out_w, 1031, 4096) if $^O eq 'linux'; # 1031: F_SETPIPE_SZ
         $out_w->autoflush(1);
         $out_w->blocking(0);
-        $self->SUPER::new($out_w, 0); # EPOLL_CTL_ADD (a bit wasteful :x)
         $self->{inflight} = [];
+        $self->SUPER::new($out_w, EPOLLONESHOT); # detect errors once
 }
 
 sub fail {
@@ -39,22 +40,28 @@ sub fail {
 
 sub cat_async ($$$;$) {
         my ($self, $req, $cb, $arg) = @_;
-        my $inflight = $self->{inflight} // gcf2c_begin($self);
+        my $inflight = $self->{inflight};
 
-        # rare, I hope:
+        # {wbuf} is rare, I hope:
         cat_async_step($self, $inflight) if $self->{wbuf};
 
-        $self->write(\"$req\n") or $self->fail("gcf2c write: $!");
+        if (!$self->write(\"$req\n")) {
+                $self->fail("gcf2c write: $!") if !$self->{sock};
+        }
         push @$inflight, $req, $cb, $arg;
 }
 
 # ensure PublicInbox::Git::cat_async_step never calls cat_async_retry
 sub alternates_changed {}
 
-no warnings 'once';
-
 # this is the write-only end of a pipe, DS->EventLoop will call this
-*event_step = \&PublicInbox::DS::flush_write;
+sub event_step {
+        my ($self) = @_;
+        $self->flush_write;
+        $self->close if !$self->{in}; # process died
+}
+
+no warnings 'once';
 
 # used by GitAsyncCat
 *cat_async_step = \&PublicInbox::Git::cat_async_step;
diff --git a/lib/PublicInbox/GitAsyncCat.pm b/lib/PublicInbox/GitAsyncCat.pm
index b9dbe0cc..be51f673 100644
--- a/lib/PublicInbox/GitAsyncCat.pm
+++ b/lib/PublicInbox/GitAsyncCat.pm
@@ -53,14 +53,21 @@ sub event_step {
 
 sub git_async_cat ($$$$) {
         my ($git, $oid, $cb, $arg) = @_;
-        my $gitish = $GCF2C;
-        if ($gitish) {
+        my $gitish = $GCF2C //= eval {
+                require PublicInbox::Gcf2;
+                require PublicInbox::Gcf2Client;
+                PublicInbox::Gcf2Client::new();
+        } // 0; # 0: do not retry if libgit2 or Inline::C are missing
+        if ($gitish) { # Gcf2 active, {inflight} may be unset due to errors
+                $GCF2C->{inflight} or
+                        $gitish = $GCF2C = PublicInbox::Gcf2Client::new();
                 $oid .= " $git->{git_dir}";
         } else {
                 $gitish = $git;
         }
         $gitish->cat_async($oid, $cb, $arg);
         $gitish->{async_cat} //= do {
+                # read-only end of pipe (Gcf2Client is write-only end)
                 my $self = bless { gitish => $gitish }, __PACKAGE__;
                 $self->SUPER::new($gitish->{in}, EPOLLIN|EPOLLET);
                 \undef; # this is a true ref()