/*  * 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 "../port/lib.h"#include "mem.h"#include "dat.h"#include "fns.h"#include "../port/error.h"#include "io.h" enum {	Qdir = 0,	Qbase, 	Qmax = 16,}; typedef long Rdwrfn(Chan*, void*, long, vlong); static Rdwrfn *readfn[Qmax];static Rdwrfn *writefn[Qmax]; static Dirtab archdir[Qmax] = {	".",		{ Qdir, 0, QTDIR },	0,	0555,}; Lock archwlock;	/* the lock is only for changing archdir */int narchdir = Qbase; /* * Add a file to the #P listing.  Once added, you can't delete it. * You can't add a file with the same name as one already there, * and you get a pointer to the Dirtab entry so you can do things * like change the Qid version.  Changing the Qid path is disallowed. */Dirtab*addarchfile(char *name, int perm, Rdwrfn *rdfn, Rdwrfn *wrfn){	int i;	Dirtab d;	Dirtab *dp; 	memset(&d, 0, sizeof d);	strcpy(d.name, name);	d.perm = perm; 	lock(&archwlock);	if(narchdir >= Qmax){		unlock(&archwlock);		return nil;	} 	for(i=0; i<narchdir; i++)		if(strcmp(archdir[i].name, name) == 0){			unlock(&archwlock);			return nil;		} 	d.qid.path = narchdir;	archdir[narchdir] = d;	readfn[narchdir] = rdfn;	writefn[narchdir] = wrfn;	dp = &archdir[narchdir++];	unlock(&archwlock); 	return dp;} static Chan*archattach(char* spec){	return devattach('P', spec);} Walkqid*archwalk(Chan* c, Chan *nc, char** name, int nname){	return devwalk(c, nc, name, nname, archdir, narchdir, devgen);} static intarchstat(Chan* c, uchar* dp, int n){	return devstat(c, dp, n, archdir, narchdir, devgen);} static Chan*archopen(Chan* c, int omode){	return devopen(c, omode, archdir, narchdir, devgen);} static voidarchclose(Chan*){} static longarchread(Chan *c, void *a, long n, vlong offset){	Rdwrfn *fn; 	switch((ulong)c->qid.path){	case Qdir:		return devdirread(c, a, n, archdir, narchdir, devgen); 	default:		if(c->qid.path < narchdir && (fn = readfn[c->qid.path]))			return fn(c, a, n, offset);		error(Eperm);		break;	} 	return 0;} static longarchwrite(Chan *c, void *a, long n, vlong offset){	Rdwrfn *fn; 	if(c->qid.path < narchdir && (fn = writefn[c->qid.path]))		return fn(c, a, n, offset);	error(Eperm); 	return 0;} void archinit(void); Dev archdevtab = {	'P',	"arch", 	devreset,	archinit,	devshutdown,	archattach,	archwalk,	archstat,	archopen,	devcreate,	archclose,	archread,	devbread,	archwrite,	devbwrite,	devremove,	devwstat,}; static longcputyperead(Chan*, void *a, long n, vlong offset){	char str[128]; 	snprint(str, sizeof str, "ARM11 %d\n", m->cpumhz);	return readstr(offset, a, n, str);} voidarchinit(void){	addarchfile("cputype", 0444, cputyperead, nil);}