Subversion Repositories planix.SVN

#include <u.h>

#include <libc.h>

#include <fcall.h>

#include <thread.h>

#include <9p.h>

#include <auth.h>

static void postproc(void*);

void

_postmountsrv(Srv *s, char *name, char *mtpt, int flag)

{

	int fd[2];

	if(!s->nopipe){

		if(pipe(fd) < 0)

			sysfatal("pipe: %r");

		s->infd = s->outfd = fd[1];

		s->srvfd = fd[0];

	}

	if(name)

		if(postfd(name, s->srvfd) < 0)

			sysfatal("postfd %s: %r", name);

	if(_forker == nil)

		sysfatal("no forker");

	_forker(postproc, s, RFNAMEG);

	/*

	 * Normally the server is posting as the last thing it does

	 * before exiting, so the correct thing to do is drop into

	 * a different fd space and close the 9P server half of the

	 * pipe before trying to mount the kernel half.  This way,

	 * if the file server dies, we don't have a ref to the 9P server

	 * half of the pipe.  Then killing the other procs will drop

	 * all the refs on the 9P server half, and the mount will fail.

	 * Otherwise the mount hangs forever.

	 *

	 * Libthread in general and acme win in particular make

	 * it hard to make this fd bookkeeping work out properly,

	 * so leaveinfdopen is a flag that win sets to opt out of this

	 * safety net.

	 */

	if(!s->leavefdsopen){

		rfork(RFFDG);

		rendezvous(0, 0);

		close(s->infd);

		if(s->infd != s->outfd)

			close(s->outfd);

	}

	if(mtpt){

		if(amount(s->srvfd, mtpt, flag, "") == -1)

			sysfatal("mount %s: %r", mtpt);

	}else

		close(s->srvfd);

}

static void

postproc(void *v)

{

	Srv *s;

	s = v;

	if(!s->leavefdsopen){

		rfork(RFNOTEG);

		rendezvous(0, 0);

		close(s->srvfd);

	}

	srv(s);

}