t/httpd-corner: improve reliability and diagnostics

The graceful-shutdown-on-PUT test is unreliable because we can't
rely on a FIFO as we do with the GET tests.  So increase the
delay to 100ms since that seems enough on my system even with
CONFIG_HZ=100.

Add a timeout and backtrace to the $check_self sub to help with
further diagnostics while we're at it, too.

It would be nice if there were a portable syscall tracing
mechanism we could attach to the -httpd process to make the test
more determistic...

diff --git a/t/httpd-corner.t b/t/httpd-corner.t
index 21b5c560db1901989d58a98a2f9ab2c165f628d5..f25a9a9cb31d0ae5198687cdb37495d57ca9cff7 100644 (file)
--- a/t/httpd-corner.t
+++ b/t/httpd-corner.t
@@ -16,6 +16,7 @@ use IO::Socket::UNIX;
 use Fcntl qw(:seek);
 use Socket qw(IPPROTO_TCP TCP_NODELAY SOL_SOCKET);
 use POSIX qw(mkfifo);
+use Carp ();
 my ($tmpdir, $for_destroy) = tmpdir();
 my $fifo = "$tmpdir/fifo";
 ok(defined mkfifo($fifo, 0777), 'created FIFO');
@@ -298,6 +299,8 @@ my $len = length $str;
 is($len, 26, 'got the alphabet');
 my $check_self = sub {
        my ($conn) = @_;
+       vec(my $rbits, fileno($conn), 1) = 1;
+       select($rbits, undef, undef, 30) or Carp::confess('timed out');
        $conn->read(my $buf, 4096);
        my ($head, $body) = split(/\r\n\r\n/, $buf, 2);
        like($head, qr/\r\nContent-Length: 40\r\n/s, 'got expected length');
@@ -391,17 +394,20 @@ SKIP: {
 
 {
        my $conn = conn_for($sock, 'graceful termination during slow request');
-       $conn->write("PUT /sha1 HTTP/1.0\r\n");
-       delay();
-       $conn->write("Content-Length: $len\r\n");
-       delay();
-       $conn->write("\r\n");
-       is($td->kill, 1, 'started graceful shutdown');
-       delay();
+       $conn->write("PUT /sha1 HTTP/1.0\r\nContent-Length: $len\r\n\r\n");
+
+       # XXX ugh, want a reliable and non-intrusive way to detect
+       # that the server has started buffering our partial request so we
+       # can reliably test graceful termination.  Maybe making this and
+       # similar tests dependent on Linux strace is a possibility?
+       delay(0.1);
+
+       is($td->kill, 1, 'start graceful shutdown');
        my $n = 0;
        foreach my $c ('a'..'z') {
                $n += $conn->write($c);
        }
+       ok(kill(0, $td->{pid}), 'graceful shutdown did not kill httpd');
        is($n, $len, 'wrote alphabet');
        $check_self->($conn);
        $td->join;