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);
}