#include	"u.h"#include	"../port/lib.h"#include	"mem.h"#include	"dat.h"#include	"fns.h"#include	"../port/error.h" enum{	Qdir=	0, 	Nfiles=32,	/* max root files */}; extern ulong	bootlen;extern uchar	bootcode[]; Dirtab rootdir[Nfiles] = {	".",	{Qdir, 0, QTDIR},	0,		DMDIR|0555,}; static uchar	*rootdata[Nfiles];static int	nroot = 1; /* *  add a root file */static voidaddroot(char *name, uchar *contents, ulong len, int perm){	Dirtab *d; 	if(nroot >= Nfiles)		panic("too many root files");	rootdata[nroot] = contents;	d = &rootdir[nroot];	strcpy(d->name, name);	d->length = len;	d->perm = perm;	d->qid.type = 0;	d->qid.vers = 0;	d->qid.path = nroot+1;	if(perm & DMDIR)		d->qid.type |= QTDIR;	nroot++;} /* *  add a root file */voidaddrootfile(char *name, uchar *contents, ulong len){	addroot(name, contents, len, 0555);} /* *  add a root file */static voidaddrootdir(char *name){	addroot(name, nil, 0, DMDIR|0555);} static voidrootreset(void){	addrootdir("bin");	addrootdir("dev");	addrootdir("env");	addrootdir("fd");	addrootdir("mnt");	addrootdir("net");	addrootdir("net.alt");	addrootdir("proc");	addrootdir("root");	addrootdir("srv"); 	addrootfile("boot", bootcode, bootlen);	/* always have a boot file */} static Chan*rootattach(char *spec){	return devattach('/', spec);} static Walkqid*rootwalk(Chan *c, Chan *nc, char **name, int nname){	return devwalk(c,  nc, name, nname, rootdir, nroot, devgen);} static introotstat(Chan *c, uchar *dp, int n){	return devstat(c, dp, n, rootdir, nroot, devgen);} static Chan*rootopen(Chan *c, int omode){	switch((ulong)c->qid.path) {	default:		break;	} 	return devopen(c, omode, rootdir, nroot, devgen);} /* * sysremove() knows this is a nop */static voidrootclose(Chan*){} static longrootread(Chan *c, void *buf, long n, vlong off){	ulong t;	Dirtab *d;	uchar *data;	ulong offset = off; 	t = c->qid.path;	switch(t){	case Qdir:		return devdirread(c, buf, n, rootdir, nroot, devgen);	} 	d = &rootdir[t-1];	data = rootdata[t-1];	if(offset >= d->length)		return 0;	if(offset+n > d->length)		n = d->length - offset;	memmove(buf, data+offset, n);	return n;} static longrootwrite(Chan *c, void*, long, vlong){	switch((ulong)c->qid.path){	default:		error(Egreg);	}	return 0;} Dev rootdevtab = {	'/',	"root", 	rootreset,	devinit,	devshutdown,	rootattach,	rootwalk,	rootstat,	rootopen,	devcreate,	rootclose,	rootread,	devbread,	rootwrite,	devbwrite,	devremove,	devwstat,};