/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include <u.h>#include <libc.h>#include "compat.h" typedef struct Exporter	Exporter;struct Exporter{	int	fd;	Chan	**roots;	int	nroots;}; intmounter(char *mntpt, int how, int fd, int n){	char buf[32];	int i, ok, mfd; 	ok = 1;	for(i = 0; i < n; i++){		snprint(buf, sizeof buf, "%d", i);		mfd = dup(fd, -1);		if(mount(mfd, -1, mntpt, how, buf) == -1){			close(mfd);			fprint(2, "can't mount on %s: %r\n", mntpt);			ok = 0;			break;		}		close(mfd);		if(how == MREPL)			how = MAFTER;	} 	close(fd); 	return ok;} static voidextramp(void *v){	Exporter *ex; 	rfork(RFNAMEG);	ex = v;	sysexport(ex->fd, ex->roots, ex->nroots);	shutdown();	exits(nil);} intexporter(Dev **dt, int *fd, int *sfd){	Chan **roots;	Exporter ex;	int p[2], i, n, ed; 	for(n = 0; dt[n] != nil; n++)		;	if(!n){		werrstr("no devices specified");		return 0;	} 	ed = errdepth(-1);	if(waserror()){		werrstr(up->error);		return 0;	} 	roots = smalloc(n * sizeof *roots);	for(i = 0; i < n; i++){		(*dt[i]->reset)();		(*dt[i]->init)();		roots[i] = (*dt[i]->attach)("");	}	poperror();	errdepth(ed); 	if(pipe(p) < 0){		werrstr("can't make pipe: %r");		return 0;	} 	*sfd = p[0];	*fd = p[1]; 	ex.fd = *sfd;	ex.roots = roots;	ex.nroots = n;	kproc("exporter", extramp, &ex); 	return n;}