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#include <u.h>
#include <libc.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
#include <auth.h>
#include "post.h"
Postcrud*
_post1(Srv *s, char *name, char *mtpt, int flag)
{
Postcrud *p;
p = emalloc9p(sizeof *p);
if(!s->nopipe){
if(pipe(p->fd) < 0)
sysfatal("pipe: %r");
s->infd = s->outfd = p->fd[1];
s->srvfd = p->fd[0];
}
if(name)
if(postfd(name, s->srvfd) < 0)
sysfatal("postfd %s: %r", name);
p->s = s;
p->mtpt = mtpt;
p->flag = flag;
return p;
}
void
_post2(void *v)
{
Srv *s;
s = v;
rfork(RFNOTEG);
if(!s->leavefdsopen){
rendezvous((ulong)s, 0);
close(s->srvfd);
}
srv(s);
}
void
_post3(Postcrud *p)
{
/*
* 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(!p->s->leavefdsopen){
rfork(RFFDG);
rendezvous((ulong)p->s, 0);
close(p->s->infd);
if(p->s->infd != p->s->outfd)
close(p->s->outfd);
}
if(p->mtpt){
if(amount(p->s->srvfd, p->mtpt, p->flag, "") == -1)
sysfatal("mount %s: %r", p->mtpt);
}else
close(p->s->srvfd);
free(p);
}
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