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#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);
}
void
_postsharesrv(Srv *s, char *name, char *mtpt, char *desc)
{
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(sharefd(mtpt, desc, s->srvfd) < 0)
sysfatal("sharefd %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);
}
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