#include	"all.h"

void
f_nop(Chan *cp, Fcall *in, Fcall *ou)
{

	USED(in);
	USED(ou);
	if(CHAT(cp))
		print("c_nop %d\n", cp->chan);
}

void
f_flush(Chan *cp, Fcall *in, Fcall *ou)
{

	USED(in);
	USED(ou);
	if(CHAT(cp))
		print("c_flush %d\n", cp->chan);
	runlock(&cp->reflock);
	wlock(&cp->reflock);
	wunlock(&cp->reflock);
	rlock(&cp->reflock);
}

void
f_session(Chan *cp, Fcall *in, Fcall *ou)
{

	USED(in);
	USED(ou);
	if(CHAT(cp))
		print("c_session %d\n", cp->chan);
	fileinit(cp);
}

void
f_attach(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p;
	Dentry *d;
	File *f;
	int u;
	Filsys *fs;
	long raddr;

	if(CHAT(cp)) {
		print("c_attach %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
		print("	uid = %s\n", in->uname);
		print("	arg = %s\n", in->aname);
	}

	ou->qid = QID(0,0);
	ou->fid = in->fid;
	if(!in->aname[0])	/* default */
		strncpy(in->aname, "main", sizeof(in->aname));
	p = 0;
	f = filep(cp, in->fid, 1);
	if(!f) {
		ou->err = Efid;
		goto out;
	}

	u = -1;
	if(cp != cons.chan) {
		if(noattach) {
			ou->err = Enoattach;
			goto out;
		}
		u = strtouid(in->uname, 1);
		if(u < 0 && cp != cons.chan) {
			ou->err = Ebadu;
			goto out;
		}
		if(authorise(f, in) == 0 || strcmp(in->uname, "adm") == 0) {
			ou->err = Eauth;
			goto out;
		}
	}

	fs = fsstr(in->aname);
	if(fs == 0) {
		ou->err = Ebadspc;
		goto out;
	}
	raddr = getraddr(fs->dev);
	p = getbuf(fs->dev, raddr, Bread);
	d = getdir(p, 0);
	if(!d || checktag(p, Tdir, QPROOT) || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(iaccess(f, d, DREAD)) {
		ou->err = Eaccess;
		goto out;
	}
	if(u == 0 && fs->dev.type == Devro) {
		/*
		 * 'none' not allowed on dump
		 */
		ou->err = Eaccess;
		goto out;
	}
	f->uid = u;
	accessdir(p, d, FREAD);
	f->qid.path = fakeqid(d);
	f->qid.version = d->qid.version;
	f->fs = fs;
	f->addr = raddr;
	f->slot = 0;
	f->open = 0;
	freewp(f->wpath);
	f->wpath = 0;

	ou->qid = f->qid;

	strncpy(cp->whoname, in->uname, sizeof(cp->whoname));
	cp->whotime = time();
	if(cons.flags & attachflag)
		print("attach %s %T to \"%s\" C%d\n",
			cp->whoname, cp->whotime, fs->name, cp->chan);

out:
	if((cons.flags & attachflag) && ou->err)
		print("attach %s %T SUCK EGGS --- %s\n",
			in->uname, time(), errstr[ou->err]);
	if(p)
		putbuf(p);
	if(f)
		qunlock(f);
}

void
f_clwalk(Chan *cp, Fcall *in, Fcall *ou)
{
	int er, fid;

	if(CHAT(cp))
		print("c_clwalk macro\n");

	f_clone(cp, in, ou);		/* sets tag, fid */
	if(ou->err)
		return;
	fid = in->fid;
	in->fid = in->newfid;
	f_walk(cp, in, ou);		/* sets tag, fid, qid */
	er = ou->err;
	if(er == Eentry) {
		/*
		 * if error is "no entry"
		 * return non error and fid
		 */
		ou->err = 0;
		f_clunk(cp, in, ou);	/* sets tag, fid */
		ou->err = 0;
		ou->fid = fid;
		if(CHAT(cp)) 
			print("	error: %s\n", errstr[er]);
		return;
	}
	if(er) {
		/*
		 * if any other error
		 * return an error
		 */
		ou->err = 0;
		f_clunk(cp, in, ou);	/* sets tag, fid */
		ou->err = er;
		return;
	}
	/*
	 * non error
	 * return newfid
	 */
}

void
f_clone(Chan *cp, Fcall *in, Fcall *ou)
{
	File *f1, *f2;
	Wpath *p;
	int fid, fid1;

	if(CHAT(cp)) {
		print("c_clone %d\n", cp->chan);
		print("	old fid = %d\n", in->fid);
		print("	new fid = %d\n", in->newfid);
	}

	fid = in->fid;
	fid1 = in->newfid;

	f1 = 0;
	f2 = 0;
	if(fid < fid1) {
		f1 = filep(cp, fid, 0);
		f2 = filep(cp, fid1, 1);
	} else
	if(fid1 < fid) {
		f2 = filep(cp, fid1, 1);
		f1 = filep(cp, fid, 0);
	}
	if(!f1 || !f2) {
		ou->err = Efid;
		goto out;
	}


	f2->fs = f1->fs;
	f2->addr = f1->addr;
	f2->open = f1->open & ~FREMOV;
	f2->uid = f1->uid;
	f2->slot = f1->slot;
	f2->qid = f1->qid;

	freewp(f2->wpath);
	lock(&wpathlock);
	f2->wpath = f1->wpath;
	for(p = f2->wpath; p; p = p->up)
		p->refs++;
	unlock(&wpathlock);

out:
	ou->fid = fid;
	if(f1)
		qunlock(f1);
	if(f2)
		qunlock(f2);
}

void
f_walk(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p, *p1;
	Dentry *d, *d1;
	File *f;
	Wpath *w;
	int slot;
	long addr;

	if(CHAT(cp)) {
		print("c_walk %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
		print("	name = %s\n", in->name);
	}

	ou->fid = in->fid;
	ou->qid = QID(0,0);
	p = 0;
	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	p = getbuf(f->fs->dev, f->addr, Bread);
	d = getdir(p, f->slot);
	if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(!(d->mode & DDIR)) {
		ou->err = Edir1;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		ou->err = Eqid;
		goto out;
	}
	if(cp != cons.chan && iaccess(f, d, DEXEC)) {
		ou->err = Eaccess;
		goto out;
	}
	accessdir(p, d, FREAD);
	if(strcmp(in->name, ".") == 0)
		goto setdot;
	if(strcmp(in->name, "..") == 0) {
		if(f->wpath == 0)
			goto setdot;
		putbuf(p);
		p = 0;
		addr = f->wpath->addr;
		slot = f->wpath->slot;
		p1 = getbuf(f->fs->dev, addr, Bread);
		d1 = getdir(p1, slot);
		if(!d1 || checktag(p1, Tdir, QPNONE) || !(d1->mode & DALLOC)) {
			if(p1)
				putbuf(p1);
			ou->err = Ephase;
			goto out;
		}
		lock(&wpathlock);
		f->wpath->refs--;
		f->wpath = f->wpath->up;
		unlock(&wpathlock);
		goto found;
	}
	for(addr=0;; addr++) {
		p1 = dnodebuf(p, d, addr, 0);
		if(!p1 || checktag(p1, Tdir, d->qid.path) ) {
			if(p1)
				putbuf(p1);
			ou->err = Eentry;
			goto out;
		}
		for(slot=0; slot<DIRPERBUF; slot++) {
			d1 = getdir(p1, slot);
			if(!(d1->mode & DALLOC))
				continue;
			if(strncmp(in->name, d1->name, sizeof(in->name)))
				continue;
			/*
			 * update walk path
			 */
			w = newwp();
			if(!w) {
				ou->err = Ewalk;
				putbuf(p1);
				goto out;
			}
			w->addr = f->addr;
			w->slot = f->slot;
			w->up = f->wpath;
			f->wpath = w;
			slot += DIRPERBUF*addr;
			goto found;
		}
		putbuf(p1);
	}

found:
	f->addr = p1->addr;
	f->qid.path = fakeqid(d1);
	f->qid.version = d1->qid.version;
	putbuf(p1);
	f->slot = slot;

setdot:
	ou->qid = f->qid;
	f->open = 0;

out:
	if(p)
		putbuf(p);
	if(f)
		qunlock(f);
}

void
f_open(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p;
	Dentry *d;
	File *f;
	Tlock *t;
	Qid qid;
	int ro, fmod;

	if(CHAT(cp)) {
		print("c_open %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
		print("	mode = %o\n", in->mode);
	}

	p = 0;
	qid = QID(0,0);
	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}

	/*
	 * if remove on close, check access here
	 */
	ro = f->fs->dev.type == Devro;
	if(in->mode & MRCLOSE) {
		if(ro) {
			ou->err = Eronly;
			goto out;
		}
		/*
		 * check on parent directory of file to be deleted
		 */
		if(f->wpath == 0 || f->wpath->addr == f->addr) {
			ou->err = Ephase;
			goto out;
		}
		p = getbuf(f->fs->dev, f->wpath->addr, Bread);
		d = getdir(p, f->wpath->slot);
		if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
			ou->err = Ephase;
			goto out;
		}
		if(iaccess(f, d, DWRITE)) {
			ou->err = Eaccess;
			goto out;
		}
		putbuf(p);
	}
	p = getbuf(f->fs->dev, f->addr, Bread);
	d = getdir(p, f->slot);
	if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		ou->err = Eqid;
		goto out;
	}
	qid.path = fakeqid(d);
	qid.version = d->qid.version;
	switch(in->mode & 7) {

	case MREAD:
		if(iaccess(f, d, DREAD) && !writeallow)
			goto badaccess;
		fmod = FREAD;
		break;

	case MWRITE:
		if((d->mode & DDIR) ||
		   (iaccess(f, d, DWRITE) && !writeallow))
			goto badaccess;
		if(ro) {
			ou->err = Eronly;
			goto out;
		}
		fmod = FWRITE;
		break;

	case MBOTH:
		if((d->mode & DDIR) ||
		   (iaccess(f, d, DREAD) && !writeallow) ||
		   (iaccess(f, d, DWRITE) && !writeallow))
			goto badaccess;
		if(ro) {
			ou->err = Eronly;
			goto out;
		}
		fmod = FREAD+FWRITE;
		break;

	case MEXEC:
		if((d->mode & DDIR) ||
		   iaccess(f, d, DEXEC))
			goto badaccess;
		fmod = FREAD;
		break;

	default:
		ou->err = Emode;
		goto out;
	}
	if(in->mode & MTRUNC) {
		if((d->mode & DDIR) ||
		   (iaccess(f, d, DWRITE) && !writeallow))
			goto badaccess;
		if(ro) {
			ou->err = Eronly;
			goto out;
		}
	}
	t = 0;
	if(d->mode & DLOCK) {
		t = tlocked(p, d);
		if(t == 0) {
			ou->err = Elocked;
			goto out;
		}
		t->file = f;
	}
	if(in->mode & MRCLOSE)
		fmod |= FREMOV;
	f->open = fmod;
	if(in->mode & MTRUNC)
		if(!(d->mode & DAPND))
			dtrunc(p, d);
	f->tlock = t;
	f->lastra = 0;
	goto out;

badaccess:
	ou->err = Eaccess;
	f->open = 0;

out:
	if(p)
		putbuf(p);
	if(f)
		qunlock(f);
	ou->fid = in->fid;
	ou->qid = qid;
}

void
f_create(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p, *p1;
	Dentry *d, *d1;
	File *f;
	int slot, slot1, fmod;
	long addr, addr1;
	Qid qid;
	Tlock *t;
	Wpath *w;

	if(CHAT(cp)) {
		print("c_create %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
		print("	name = %s\n", in->name);
		print("	perm = %x+%o\n", (in->perm>>28)&0xf,
				in->perm&0777);
		print("	mode = %d\n", in->mode);
	}

	p = 0;
	qid = QID(0,0);
	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	if(f->fs->dev.type == Devro) {
		ou->err = Eronly;
		goto out;
	}

	p = getbuf(f->fs->dev, f->addr, Bread);
	d = getdir(p, f->slot);
	if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		ou->err = Eqid;
		goto out;
	}
	if(!(d->mode & DDIR)) {
		ou->err = Edir2;
		goto out;
	}
	if(cp != cons.chan && iaccess(f, d, DWRITE) && !writeallow) {
		ou->err = Eaccess;
		goto out;
	}
	accessdir(p, d, FREAD);
	if(!strncmp(in->name, ".", sizeof(in->name)) ||
	   !strncmp(in->name, "..", sizeof(in->name))) {
		ou->err = Edot;
		goto out;
	}
	if(checkname(in->name)) {
		ou->err = Ename;
		goto out;
	}
	addr1 = 0;
	slot1 = 0;	/* set */
	for(addr=0;; addr++) {
		p1 = dnodebuf(p, d, addr, 0);
		if(!p1) {
			if(addr1)
				break;
			p1 = dnodebuf(p, d, addr, Tdir);
		}
		if(p1 == 0) {
			ou->err = Efull;
			goto out;
		}
		if(checktag(p1, Tdir, d->qid.path)) {
			putbuf(p1);
			goto phase;
		}
		for(slot=0; slot<DIRPERBUF; slot++) {
			d1 = getdir(p1, slot);
			if(!(d1->mode & DALLOC)) {
				if(!addr1) {
					addr1 = p1->addr;
					slot1 = slot + addr*DIRPERBUF;
				}
				continue;
			}
			if(!strncmp(in->name, d1->name, sizeof(in->name))) {
				putbuf(p1);
				ou->err = Eexist;
				goto out;
			}
		}
		putbuf(p1);
	}
	switch(in->mode & 7) {
	case MEXEC:
	case MREAD:		/* seems only useful to make directories */
		fmod = FREAD;
		break;

	case MWRITE:
		fmod = FWRITE;
		break;

	case MBOTH:
		fmod = FREAD+FWRITE;
		break;

	default:
		ou->err = Emode;
		goto out;
	}
	if(in->perm & PDIR)
		if((in->mode & MTRUNC) || (in->perm & PAPND) || (fmod & FWRITE))
			goto badaccess;
	/*
	 * do it
	 */
	qid = newqid(f->fs->dev);
	p1 = getbuf(f->fs->dev, addr1, Bread|Bimm|Bmod);
	d1 = getdir(p1, slot1);
	if(!d1 || checktag(p1, Tdir, d->qid.path)) {
		if(p1)
			putbuf(p1);
		goto phase;
	}
	if(d1->mode & DALLOC) {
		putbuf(p1);
		goto phase;
	}

	strncpy(d1->name, in->name, sizeof(in->name));
	if(cp == cons.chan) {
		d1->uid = cons.uid;
		d1->gid = cons.gid;
	} else {
		d1->uid = f->uid;
		d1->gid = d->gid;
		in->perm &= d->mode | ~0666;
		if(in->perm & PDIR)
			in->perm &= d->mode | ~0777;
	}
	d1->mode = DALLOC | (in->perm & 0777);
	if(in->perm & PDIR) {
		d1->mode |= DDIR;
		qid.path |= QPDIR;
	}
	d1->qid = qid;
	if(in->perm & PAPND)
		d1->mode |= DAPND;
	t = 0;
	if(in->perm & PLOCK) {
		d1->mode |= DLOCK;
		t = tlocked(p1, d1);
	}
	accessdir(p1, d1, FWRITE);
	putbuf(p1);
	accessdir(p, d, FWRITE);

	/*
	 * do a walk to new directory entry
	 */
	w = newwp();
	if(!w) {
		ou->err = Ewalk;
		goto out;
	}
	w->addr = f->addr;
	w->slot = f->slot;
	w->up = f->wpath;
	f->wpath = w;
	f->qid = qid;
	f->tlock = t;
	f->lastra = 0;
	if(in->mode & MRCLOSE)
		fmod |= FREMOV;
	f->open = fmod;
	f->addr = addr1;
	f->slot = slot1;
	if(t)
		t->file = f;
	goto out;

badaccess:
	ou->err = Eaccess;
	goto out;

phase:
	ou->err = Ephase;

out:
	if(p)
		putbuf(p);
	if(f)
		qunlock(f);
	ou->fid = in->fid;
	ou->qid = qid;
}

void
f_read(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p, *p1;
	File *f;
	Dentry *d, *d1;
	Tlock *t;
	long addr, offset, tim;
	int nread, count, n, o, slot;

	if(CHAT(cp)) {
		print("c_read %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
		print("	offset = %ld\n", in->offset);
		print("	count = %d\n", in->count);
	}

	p = 0;
	count = in->count;
	offset = in->offset;
	nread = 0;
	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	if(!(f->open & FREAD)) {
		ou->err = Eopen;
		goto out;
	}
	if(count < 0 || count > MAXDAT) {
		ou->err = Ecount;
		goto out;
	}
	if(offset < 0) {
		ou->err = Eoffset;
		goto out;
	}
	p = getbuf(f->fs->dev, f->addr, Bread);
	d = getdir(p, f->slot);
	if(!d || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		ou->err = Eqid;
		goto out;
	}
	if(t = f->tlock) {
		tim = toytime();
		if(t->time < tim || t->file != f) {
			ou->err = Ebroken;
			goto out;
		}
		/* renew the lock */
		t->time = tim + TLOCK;
	}
	accessdir(p, d, FREAD);
	if(d->mode & DDIR) {
		addr = 0;
		goto dread;
	}
	if(offset+count > d->size)
		count = d->size - offset;
	while(count > 0) {
		addr = offset / BUFSIZE;
		if(addr == f->lastra+1)
			dbufread(p, d, addr+1);
		f->lastra = addr;
		o = offset % BUFSIZE;
		n = BUFSIZE - o;
		if(n > count)
			n = count;
		p1 = dnodebuf(p, d, addr, 0);
		if(p1) {
			if(checktag(p1, Tfile, QPNONE)) {
				ou->err = Ephase;
				putbuf(p1);
				goto out;
			}
			memmove(ou->data+nread, p1->iobuf+o, n);
			putbuf(p1);
		} else
			memset(ou->data+nread, 0, n);
		count -= n;
		nread += n;
		offset += n;
	}
	goto out;

dread:
	p1 = dnodebuf(p, d, addr, 0);
	if(!p1)
		goto out;
	if(checktag(p1, Tdir, QPNONE)) {
		ou->err = Ephase;
		putbuf(p1);
		goto out;
	}
	n = DIRREC;
	for(slot=0; slot<DIRPERBUF; slot++) {
		d1 = getdir(p1, slot);
		if(!(d1->mode & DALLOC))
			continue;
		if(offset >= n) {
			offset -= n;
			continue;
		}
		if(count < n) {
			putbuf(p1);
			goto out;
		}
		if(convD2M(d1, ou->data+nread) != n)
			print("dirread convD2M\n");
		nread += n;
		count -= n;
	}
	putbuf(p1);
	addr++;
	goto dread;

out:
	count = in->count - nread;
	if(count > 0)
		memset(ou->data+nread, 0, count);
	if(p)
		putbuf(p);
	if(f)
		qunlock(f);
	ou->fid = in->fid;
	ou->count = nread;
	if(CHAT(cp))
		print("	nread = %d\n", nread);
}

void
f_write(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p, *p1;
	Dentry *d;
	File *f;
	Tlock *t;
	long offset, addr, tim;
	int count, nwrite, o, n;

	if(CHAT(cp)) {
		print("c_write %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
		print("	offset = %ld\n", in->offset);
		print("	count = %d\n", in->count);
	}

	offset = in->offset;
	count = in->count;
	nwrite = 0;
	p = 0;
	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	if(!(f->open & FWRITE)) {
		ou->err = Eopen;
		goto out;
	}
	if(f->fs->dev.type == Devro) {
		ou->err = Eronly;
		goto out;
	}
	if(count < 0 || count > MAXDAT) {
		ou->err = Ecount;
		goto out;
	}
	if(offset < 0) {
		ou->err = Eoffset;
		goto out;
	}
	p = getbuf(f->fs->dev, f->addr, Bread|Bmod);
	d = getdir(p, f->slot);
	if(!d || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		ou->err = Eqid;
		goto out;
	}
	if(t = f->tlock) {
		tim = toytime();
		if(t->time < tim || t->file != f) {
			ou->err = Ebroken;
			goto out;
		}
		/* renew the lock */
		t->time = tim + TLOCK;
	}
	accessdir(p, d, FWRITE);
	if(d->mode & DAPND)
		offset = d->size;
	if(offset+count > d->size)
		d->size = offset+count;
	while(count > 0) {
		addr = offset / BUFSIZE;
		o = offset % BUFSIZE;
		n = BUFSIZE - o;
		if(n > count)
			n = count;
		p1 = dnodebuf(p, d, addr, Tfile);
		if(p1 == 0) {
			ou->err = Efull;
			goto out;
		}
		if(checktag(p1, Tfile, d->qid.path)) {
			putbuf(p1);
			ou->err = Ephase;
			goto out;
		}
		memmove(p1->iobuf+o, in->data+nwrite, n);
		p1->flags |= Bmod;
		putbuf(p1);
		count -= n;
		nwrite += n;
		offset += n;
	}
	if(CHAT(cp))
		print("	nwrite = %d\n", nwrite);

out:
	if(p)
		putbuf(p);
	if(f)
		qunlock(f);
	ou->fid = in->fid;
	ou->count = nwrite;
}

int
doremove(File *f, int iscon)
{
	Iobuf *p, *p1;
	Dentry *d, *d1;
	long addr;
	int slot, err;

	err = 0;
	p = 0;
	p1 = 0;
	if(f->fs->dev.type == Devro) {
		err = Eronly;
		goto out;
	}
	/*
	 * check on parent directory of file to be deleted
	 */
	if(f->wpath == 0 || f->wpath->addr == f->addr) {
		err = Ephase;
		goto out;
	}
	p1 = getbuf(f->fs->dev, f->wpath->addr, Bread);
	d1 = getdir(p1, f->wpath->slot);
	if(!d1 || checktag(p1, Tdir, QPNONE) || !(d1->mode & DALLOC)) {
		err = Ephase;
		goto out;
	}
	if(!iscon && iaccess(f, d1, DWRITE)) {
		err = Eaccess;
		goto out;
	}
	accessdir(p1, d1, FWRITE);
	putbuf(p1);
	p1 = 0;

	/*
	 * check on file to be deleted
	 */
	p = getbuf(f->fs->dev, f->addr, Bread);
	d = getdir(p, f->slot);
	if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
		err = Ealloc;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		err = Eqid;
		goto out;
	}

	/*
	 * if deleting a directory, make sure it is empty
	 */
	if((d->mode & DDIR))
	for(addr=0;; addr++) {
		p1 = dnodebuf(p, d, addr, 0);
		if(!p1)
			break;
		if(checktag(p1, Tdir, d->qid.path)) {
			err = Ephase;
			goto out;
		}
		for(slot=0; slot<DIRPERBUF; slot++) {
			d1 = getdir(p1, slot);
			if(!(d1->mode & DALLOC))
				continue;
			err = Eempty;
			goto out;
		}
		putbuf(p1);
	}

	/*
	 * do it
	 */
	dtrunc(p, d);
	memset(d, 0, sizeof(Dentry));
	settag(p, Tdir, QPNONE);

out:
	if(p1)
		putbuf(p1);
	if(p)
		putbuf(p);
	return err;
}

void
f_clunk(Chan *cp, Fcall *in, Fcall *ou)
{
	File *f;
	Tlock *t;
	long tim;

	if(CHAT(cp)) {
		print("c_clunk %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
	}

	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	if(t = f->tlock) {
		tim = toytime();
		if(t->time < tim || t->file != f)
			ou->err = Ebroken;
		t->time = 0;	/* free the lock */
		f->tlock = 0;
	}
	if(f->open & FREMOV)
		ou->err = doremove(f, 0);
	f->open = 0;
	freewp(f->wpath);
	freefp(f);

out:
	if(f)
		qunlock(f);
	ou->fid = in->fid;
}

void
f_remove(Chan *cp, Fcall *in, Fcall *ou)
{
	File *f;

	if(CHAT(cp)) {
		print("c_remove %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
	}

	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	ou->err = doremove(f, cp==cons.chan);

out:
	ou->fid = in->fid;
	if(f)
		qunlock(f);
}

void
f_stat(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p;
	Dentry *d;
	File *f;

	if(CHAT(cp)) {
		print("c_stat %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
	}

	p = 0;
	memset(ou->stat, 0, sizeof(ou->stat));
	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	p = getbuf(f->fs->dev, f->addr, Bread);
	d = getdir(p, f->slot);
	if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		ou->err = Eqid;
		goto out;
	}
	if(d->qid.path == QPROOT)	/* stat of root gives time */
		d->atime = time();
	if(convD2M(d, ou->stat) != DIRREC)
		print("stat convD2M\n");

out:
	if(p)
		putbuf(p);
	if(f)
		qunlock(f);
	ou->fid = in->fid;
}

void
f_wstat(Chan *cp, Fcall *in, Fcall *ou)
{
	Iobuf *p, *p1;
	Dentry *d, *d1, xd;
	File *f;
	int slot;
	long addr;

	if(CHAT(cp)) {
		print("c_wstat %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
	}

	p = 0;
	p1 = 0;
	d1 = 0;
	f = filep(cp, in->fid, 0);
	if(!f) {
		ou->err = Efid;
		goto out;
	}
	if(f->fs->dev.type == Devro) {
		ou->err = Eronly;
		goto out;
	}

	/*
	 * first get parent
	 */
	if(f->wpath) {
		p1 = getbuf(f->fs->dev, f->wpath->addr, Bread);
		d1 = getdir(p1, f->wpath->slot);
		if(!d1 || checktag(p1, Tdir, QPNONE) || !(d1->mode & DALLOC)) {
			ou->err = Ephase;
			goto out;
		}
	}

	p = getbuf(f->fs->dev, f->addr, Bread);
	d = getdir(p, f->slot);
	if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
		ou->err = Ealloc;
		goto out;
	}
	if(fakeqid(d) != f->qid.path) {
		ou->err = Eqid;
		goto out;
	}

	convM2D(in->stat, &xd);
	if(CHAT(cp)) {
		print("	d.name = %s\n", xd.name);
		print("	d.uid  = %d\n", xd.uid);
		print("	d.gid  = %d\n", xd.gid);
		print("	d.mode = %.4x\n", xd.mode);
	}

	/*
	 * if chown,
	 * must be god
	 */
	while(xd.uid != d->uid) {
		if(wstatallow)			/* set to allow chown during boot */
			break;
		ou->err = Enotu;
		goto out;
	}

	/*
	 * if chgroup,
	 * must be either
	 *	a) owner and in new group
	 *	b) leader of both groups
	 */
	while(xd.gid != d->gid) {
		if(wstatallow || writeallow)		/* set to allow chgrp during boot */
			break;
		if(d->uid == f->uid && ingroup(f->uid, xd.gid))
			break;
		if(leadgroup(f->uid, xd.gid))
			if(leadgroup(f->uid, d->gid))
				break;
		ou->err = Enotg;
		goto out;
	}

	/*
	 * if rename,
	 * must have write permission in parent
	 */
	while(strncmp(d->name, xd.name, sizeof(d->name)) != 0) {
		if(checkname(xd.name)) {
			ou->err = Ename;
			goto out;
		}

		/*
		 * drop entry to prevent lock, then
		 * check that destination name is unique,
		 */
		putbuf(p);
		for(addr=0;; addr++) {
			p = dnodebuf(p1, d1, addr, 0);
			if(!p)
				break;
			if(checktag(p, Tdir, d1->qid.path)) {
				putbuf(p);
				continue;
			}
			for(slot=0; slot<DIRPERBUF; slot++) {
				d = getdir(p, slot);
				if(!(d->mode & DALLOC))
					continue;
				if(!strncmp(xd.name, d->name, sizeof(xd.name))) {
					ou->err = Eexist;
					goto out;
				}
			}
			putbuf(p);
		}

		/*
		 * reacquire entry
		 */
		p = getbuf(f->fs->dev, f->addr, Bread);
		d = getdir(p, f->slot);
		if(!d || checktag(p, Tdir, QPNONE) || !(d->mode & DALLOC)) {
			ou->err = Ephase;
			goto out;
		}

		if(wstatallow || writeallow) /* set to allow rename during boot */
			break;
		if(!d1 || iaccess(f, d1, DWRITE)) {
			ou->err = Eaccess;
			goto out;
		}
		break;
	}

	/*
	 * if mode, either
	 *	a) owner
	 *	b) leader of either group
	 */
	while((d->mode^xd.mode) & (DAPND|DLOCK|0777)) {
		if(wstatallow)			/* set to allow chmod during boot */
			break;
		if(d->uid == f->uid)
			break;
		if(leadgroup(f->uid, xd.gid))
			break;
		if(leadgroup(f->uid, d->gid))
			break;
		ou->err = Enotu;
		goto out;
	}
	d->uid = xd.uid;
	d->gid = xd.gid;
	d->mode = (xd.mode & (DAPND|DLOCK|0777)) | (d->mode & (DALLOC|DDIR));

	strncpy(d->name, xd.name, sizeof(d->name));
	accessdir(p, d, FREAD);

out:
	if(p)
		putbuf(p);
	if(p1)
		putbuf(p1);
	if(f)
		qunlock(f);
	ou->fid = in->fid;
}

/* f_auth is called from ilauth, dkauth etc. */
void
f_auth(Chan *cp, Fcall *in, Fcall *ou)
{
	char buf[256], key[DESKEYLEN];
	int i, r, k1, k2;
	File *f;

	if(CHAT(cp)) {
		print("c_auth %d\n", cp->chan);
		print("	fid = %d\n", in->fid);
	}

	f = filep(cp, in->fid, 1);
	if(!f) {
		ou->err = Efid;
		return;
	}
	ou->fid = in->fid;

	/* File system is the authtication service */
	if(authchan == 0) {	
		if(nametokey(in->uname, key)) {
			ou->err = Eauth;
			goto out;
		}

		decrypt(key, in->chal, AUTHSTR+NAMELEN);
		if(strncmp(service, in->chal+AUTHSTR, NAMELEN) != 0 &&
		   strcmp("any", in->chal+AUTHSTR) != 0) {
			ou->err = Eauth;
			goto out;
		}

		if(in->chal[0] != FScchal) {
			ou->err = Eauth;
			goto out;
		}

		in->chal[0] = FSctick;
		memmove(ou->chal, in->chal, AUTHSTR);
		f->ticket[0] = FSstick;
		for(i = 1; i < AUTHSTR; i++)
			f->ticket[i] = nrand(256);

		k1 = AUTHSTR;
		k2 = 2*AUTHSTR+DESKEYLEN;
		for(i = 0; i < DESKEYLEN; i++) {
			r = nrand(256);
			ou->chal[k1++] = r;
			ou->chal[k2++] = r;
		}

		memmove(ou->chal+AUTHSTR+DESKEYLEN, f->ticket, AUTHSTR);
		encrypt(nvr.authkey, ou->chal+AUTHSTR+DESKEYLEN, AUTHSTR+DESKEYLEN);
		encrypt(key, ou->chal, 2*AUTHSTR+2*DESKEYLEN);
		goto out;
	}

	/* Use external authentication server */

	buf[0] = FSschal;
	for(i = 1; i < AUTHSTR; i++)
		buf[i] = nrand(256);

	memmove(f->ticket, buf, AUTHSTR);
	strncpy(&buf[i], in->uname, NAMELEN);
	i += NAMELEN;
	memmove(&buf[i], in->chal, AUTHSTR+NAMELEN);
	i += AUTHSTR+NAMELEN;

	encrypt(nvr.authkey, buf, i);
	strncpy(&buf[i], service, NAMELEN);
	i += NAMELEN;

	i = authsrv(authchan, buf, i);
	if(i < 0) {
		ou->err = Eauth;
		goto out;
	}	
	
	decrypt(nvr.authkey, buf, i);

	if(buf[0] == FSerr){
		buf[AUTHSTR+ERRREC] = '\0';
		print("auth failed: %d '%s'\n", i, buf+AUTHSTR);
		ou->err = Eauth;
		goto out;;
	}

	f->ticket[0] = FSok;
	if(memcmp(f->ticket, buf, AUTHSTR) || i != AUTHSTR+2*AUTHSTR+2*DESKEYLEN){
		print("auth reply: len %d ticket mismatch\n", i);
		ou->err = Eauth;
		goto out;
	}
	memmove(ou->chal, &buf[AUTHSTR], i-AUTHSTR);
	f->ticket[0] = FSstick;
out:
	qunlock(f);
}