tests: add quit_waiter_pipe and wait_for_eof

These generalize the idiom from t/httpd-unix.t and allows them
to be used for all the lei daemon shutdown in tests.  This
speeds up the serialized run of `prove -lvw t/lei.t t/lei-daemon.t'
by roughly 8-9% or so since we're no longer sleeping and killing
the daemon in a loop.

Parallelized `make check' and `make check-run' don't show much
difference, yet.

Note that we do eliminate some kill(2) checks since those still
require retries an delays.  We assume the kernel auto-closing
FDs on process exit is a strong-enough guarantee that the
process will soon be reaped by PID:1.

These will be useful for the FUSE daemons, as well.

We'll also start introducing more uses of autodie to simplify
our code.

1 files changed, 26 insertions, 10 deletions

diff --git a/lib/PublicInbox/TestCommon.pm b/lib/PublicInbox/TestCommon.pm
index 1fdb5ebd..7b628769 100644
--- a/lib/PublicInbox/TestCommon.pm
+++ b/lib/PublicInbox/TestCommon.pm
@@ -24,6 +24,7 @@ BEGIN {
                 run_script start_script key2sub xsys xsys_e xqx eml_load tick
                 have_xapian_compact json_utf8 setup_public_inboxes create_inbox
                 create_coderepo no_scm_rights
+                quit_waiter_pipe wait_for_eof
                 tcp_host_port test_lei lei lei_ok $lei_out $lei_err $lei_opt
                 test_httpd xbail require_cmd is_xdeeply tail_f
                 ignore_inline_c_missing no_pollerfd no_coredump cfg_new);
@@ -632,12 +633,28 @@ sub need_scm_rights () {
         '(mkdir -p ~/.cache/public-inbox/inline-c) OR Socket::MsgHdr missing';
 }
 
+# returns a pipe with FD_CLOEXEC disabled on the write-end
+sub quit_waiter_pipe () {
+        use autodie qw(fcntl pipe);
+        pipe(my $r, my $w);
+        fcntl($w, F_SETFD, fcntl($w, F_GETFD, 0) & ~FD_CLOEXEC);
+        ($r, $w);
+}
+
+sub wait_for_eof ($$;$) {
+        my ($io, $msg, $sec) = @_;
+        vec(my $rset = '', fileno($io), 1) = 1;
+        ok(select($rset, undef, undef, $sec // 9), "$msg (select)");
+        is(my $line = <$io>, undef, "$msg EOF");
+}
+
 sub test_lei {
 SKIP: {
         my ($cb) = pop @_;
         my $test_opt = shift // {};
         local $lei_cwdfh;
-        opendir $lei_cwdfh, '.' or xbail "opendir .: $!";
+        use autodie qw(mkdir open opendir);
+        opendir $lei_cwdfh, '.';
         require_git(2.6, 1);
         my $mods = $test_opt->{mods} // [ 'lei' ];
         require_mods(@$mods, 2);
@@ -661,22 +678,25 @@ SKIP: {
         my $tmpdir = $test_opt->{tmpdir};
         File::Path::mkpath($tmpdir) if defined $tmpdir;
         ($tmpdir, $for_destroy) = tmpdir unless $tmpdir;
+        my ($dead_r, $dead_w);
         state $persist_xrd = $ENV{TEST_LEI_DAEMON_PERSIST_DIR};
         SKIP: {
                 $ENV{TEST_LEI_ONESHOT} and
                         xbail 'TEST_LEI_ONESHOT no longer supported';
                 my $home = "$tmpdir/lei-daemon";
-                mkdir($home, 0700) or BAIL_OUT "mkdir: $!";
+                mkdir($home, 0700);
                 local $ENV{HOME} = $home;
                 my $persist;
                 if ($persist_xrd && !$test_opt->{daemon_only}) {
                         $persist = $daemon_xrd = $persist_xrd;
                 } else {
                         $daemon_xrd = "$home/xdg_run";
-                        mkdir($daemon_xrd, 0700) or BAIL_OUT "mkdir: $!";
+                        mkdir($daemon_xrd, 0700);
+                        ($dead_r, $dead_w) = quit_waiter_pipe;
                 }
                 local $ENV{XDG_RUNTIME_DIR} = $daemon_xrd;
-                $cb->();
+                $cb->(); # likely shares $dead_w with lei-daemon
+                undef $dead_w; # so select() wakes up when daemon dies
                 if ($persist) { # remove before ~/.local gets removed
                         File::Path::rmtree([glob("$home/*")]);
                         File::Path::rmtree("$home/.config");
@@ -693,14 +713,10 @@ SKIP: {
                 }
         }; # SKIP for lei_daemon
         if ($daemon_pid) {
-                for (0..10) {
-                        kill(0, $daemon_pid) or last;
-                        tick;
-                }
-                ok(!kill(0, $daemon_pid), "$t daemon stopped");
+                wait_for_eof($dead_r, 'daemon quit pipe');
                 no_coredump $tmpdir;
                 my $f = "$daemon_xrd/lei/errors.log";
-                open my $fh, '<', $f or BAIL_OUT "$f: $!";
+                open my $fh, '<', $f;
                 my @l = <$fh>;
                 is_xdeeply(\@l, [],
                         "$t daemon XDG_RUNTIME_DIR/lei/errors.log empty");