[PATCH 1/1] os: added the -sigstop option for Upstart (or equivalent) startup.

[Oliver McFadden]

On Fri, 2010-07-16 at 01:28 +0200, ext Peter Hutterer wrote:
> On Wed, Jul 14, 2010 at 11:26:43AM +0300, Oliver McFadden wrote:
> > This is very similar to the RunFromSmartParent (implicit) option, except
> > we do not send the signal to our parent process, but our own process
> > instead, and that signal is SIGSTOP, not SIGUSR1.
> > 
> > Upstart or a similar equivalent program will detect this, realize that
> > we are ready to accept clients now, send us SIGCONT and move our job
> > status from SPAWNED to RUNNING.
> > 
> > Signed-off-by: Oliver McFadden <oliver.mcfadden at nokia.com>
> > ---
> >  include/opaque.h |    1 +
> >  os/connection.c  |    5 +++++
> >  os/utils.c       |    5 +++++
> >  3 files changed, 11 insertions(+), 0 deletions(-)
> > 
> > diff --git a/include/opaque.h b/include/opaque.h
> > index b3c7c70..dfe440c 100644
> > --- a/include/opaque.h
> > +++ b/include/opaque.h
> > @@ -55,6 +55,7 @@ extern _X_EXPORT int defaultBackingStore;
> >  extern _X_EXPORT Bool disableBackingStore;
> >  extern _X_EXPORT Bool enableBackingStore;
> >  extern _X_EXPORT Bool PartialNetwork;
> > +extern _X_EXPORT Bool RunFromSigStopParent;
> >  #ifndef NOLOGOHACK
> >  extern _X_EXPORT int logoScreenSaver;
> >  #endif
> > diff --git a/os/connection.c b/os/connection.c
> > index c143fb6..c596731 100644
> > --- a/os/connection.c
> > +++ b/os/connection.c
> > @@ -146,6 +146,8 @@ Bool NewOutputPending;		/* not yet attempted to write some new output */
> >  Bool AnyClientsWriteBlocked;	/* true if some client blocked on write */
> >  
> >  static Bool RunFromSmartParent;	/* send SIGUSR1 to parent process */
> > +Bool RunFromSigStopParent;	/* send SIGSTOP to our own process; Upstart (or
> > +				   equivalent) will send SIGCONT back. */
> >  Bool PartialNetwork;	/* continue even if unable to bind all addrs */
> >  static Pid_t ParentProcess;
> >  
> > @@ -357,6 +359,9 @@ NotifyParentProcess(void)
> >  	    kill (ParentProcess, SIGUSR1);
> >  	}
> >      }
> > +    if (RunFromSigStopParent) {
> > +	raise (SIGSTOP);
> > +    }
> >  #endif
> >  }
> >  
> > diff --git a/os/utils.c b/os/utils.c
> > index 51455cc..f30674b 100644
> > --- a/os/utils.c
> > +++ b/os/utils.c
> > @@ -527,6 +527,7 @@ void UseMsg(void)
> >  #endif
> >      ErrorF("-dumbSched             Disable smart scheduling, enable old behavior\n");
> >      ErrorF("-schedInterval int     Set scheduler interval in msec\n");
> > +    ErrorF("-sigstop               Enable SIGSTOP based startup\n");
> >      ErrorF("+extension name        Enable extension\n");
> >      ErrorF("-extension name        Disable extension\n");
> >  #ifdef XDMCP
> > @@ -922,6 +923,10 @@ ProcessCommandLine(int argc, char *argv[])
> >  	    else
> >  		UseMsg ();
> >  	}
> > +	else if ( strcmp( argv[i], "-sigstop") == 0)
> > +	{
> > +	    RunFromSigStopParent = TRUE;
> > +	}
> >  	else if ( strcmp( argv[i], "+extension") == 0)
> >  	{
> >  	    if (++i < argc)
> > -- 
> > 1.7.1.245.g7c42e
> 
> Acked-by: Peter Hutterer <peter.hutterer at who-t.net>

Thanks, though I think I've missed the merge window on this one. Oh
well... :)

-- Oliver.