Re: [PATCH 1/2] daemon: add tests

From: Jeff King <peff@peff.net>
Date: Jan 5, 2012, 02:51 UTC
Message-ID: <20120105025154.GA7326@sigill.intra.peff.net>
In-Reply-To: <m3vcoqevjm.fsf@localhost.localdomain>

On Wed, Jan 04, 2012 at 06:24:16PM -0800, Jakub Narebski wrote:

Show 9 quoted lines

> Jeff King <peff@peff.net> writes:
> 
> > As a side note, it looks like we just start the daemon with "git daemon
> > &". Doesn't that create a race condition with the tests which
> > immediately try to access it (i.e., the first test may run before the
> > daemon actually opens the socket)?
> 
> Hmmm... perhaps the trick that git-instaweb does for "plackup" web
> server would be of use here, waiting for socket to be ready?

It looks like it busy loops, which is kind of ugly.

The credential-cache helper has a similar problem. It wants to kick off a daemon if one is not already running, and then connect to it. So the daemon does:

  printf("ok\n");
  fclose(stdout);

when it has set up the socket, and the client does:

  r = read_in_full(daemon.out, buf, sizeof(buf));
  if (r < 0)
          die_errno("unable to read result code from cache daemon");
  if (r != 3 || memcmp(buf, "ok\n", 3))
          die("cache daemon did not start: %.*s", r, buf);
  /* now we can connect over the socket */

We could probably add a "--notify-when-ready" option to git-daemon to do something similar.

-Peff