#include	"dat.h"#include	"fns.h"#include	"error.h" extern Rootdata rootdata[];extern Dirtab roottab[];extern int	rootmaxq; static Chan*rootattach(char *spec){	int i;	ulong len;	Rootdata *r; 	if(*spec)		error(Ebadspec);	for (i = 0; i < rootmaxq; i++){		r = &rootdata[i];		if (r->sizep){			len = *r->sizep;			r->size = len;			roottab[i].length = len;		}	}	return devattach('/', spec);} static introotgen(Chan *c, char *name, Dirtab *tab, int nd, int s, Dir *dp){	int p, i;	Rootdata *r; 	if(s == DEVDOTDOT){		p = rootdata[c->qid.path].dotdot;		c->qid.path = p;		c->qid.type = QTDIR;		name = "#/";		if(p != 0){			for(i = 0; i < rootmaxq; i++)				if(roottab[i].qid.path == c->qid.path){					name = roottab[i].name;					break;				}		}		devdir(c, c->qid, name, 0, eve, 0555, dp);		return 1;	}	if(name != nil){		isdir(c);		r = &rootdata[(int)c->qid.path];		tab = r->ptr;		for(i=0; i<r->size; i++, tab++)			if(strcmp(tab->name, name) == 0){				devdir(c, tab->qid, tab->name, tab->length, eve, tab->perm, dp);				return 1;			}		return -1;	}	if(s >= nd)		return -1;	tab += s;	devdir(c, tab->qid, tab->name, tab->length, eve, tab->perm, dp);	return 1;} static Walkqid*rootwalk(Chan *c, Chan *nc, char **name, int nname){	ulong p; 	p = c->qid.path;	if(nname == 0)		p = rootdata[p].dotdot;	return devwalk(c, nc, name, nname, rootdata[p].ptr, rootdata[p].size, rootgen);} static introotstat(Chan *c, uchar *dp, int n){	int p; 	p = rootdata[c->qid.path].dotdot;	return devstat(c, dp, n, rootdata[p].ptr, rootdata[p].size, rootgen);} static Chan*rootopen(Chan *c, int omode){	int p; 	p = rootdata[c->qid.path].dotdot;	return devopen(c, omode, rootdata[p].ptr, rootdata[p].size, rootgen);} /* * sysremove() knows this is a nop */static void	 rootclose(Chan *c){	USED(c);} static long	 rootread(Chan *c, void *buf, long n, vlong offset){	ulong p, len;	uchar *data; 	p = c->qid.path;	if(c->qid.type & QTDIR)		return devdirread(c, buf, n, rootdata[p].ptr, rootdata[p].size, rootgen);	len = rootdata[p].size;	if(offset < 0 || offset >= len)		return 0;	if(offset+n > len)		n = len - offset;	data = rootdata[p].ptr;	memmove(buf, data+offset, n);	return n;} static long	 rootwrite(Chan *c, void *a, long n, vlong off){	USED(c); USED(a); USED(n); USED(off);	error(Eperm);	return 0;} Dev rootdevtab = {	'/',	"root", 	devinit,	rootattach,	rootwalk,	rootstat,	rootopen,	devcreate,	rootclose,	rootread,	devbread,	rootwrite,	devbwrite,	devremove,	devwstat,};