shithub: riscv

--- a/sys/man/3/srv

+++ b/sys/man/3/srv

@@ -5,7 +5,6 @@

.nf

 .B bind #s /srv

-.BI #s/ clone/

 .BI #s/ service1

 .BI #s/ service2

...

@@ -41,16 +40,6 @@

.PP

 It is an error to write more than one number into a server file,

 or to create a file with a name that is already being used.

-.PP

-A walk to

-.I clone

-creates a blank private bulletin board. Private boards are

-recursable but disjoint; walks may only descend. A process

-may get a private

-.B /srv

-by doing:

-.IP

-bind -c /srv/clone /srv

 .SH EXAMPLE

 To drop one end of a pipe into

 .BR /srv ,

--- a/sys/src/9/port/devsrv.c

+++ b/sys/src/9/port/devsrv.c

@@ -5,7 +5,6 @@

 #include	"fns.h"

 #include	"../port/error.h"

-#include	"netif.h"

 typedef struct Srv Srv;

 struct Srv

@@ -18,34 +17,16 @@

 	ulong	path;

};

-typedef struct Fid Fid;

-struct Fid

-{

-	int	ref;

-	QLock 	lk;

-	Srv 	*tail;

-	ulong 	nextpath;

-};

+static QLock	srvlk;

+static Srv	*srv;

+static int	qidpath;

-enum{

-	Qroot,

-	Qclone,

-	Qend

-};

-static Fid global;

-struct {

-	QLock;

-	ulong path;

-} sessions;

 static Srv*

-srvlookup(Srv *sp, char *name, ulong qidpath)

+srvlookup(char *name, ulong qidpath)

-	qidpath = NETTYPE(qidpath);

-	for(; sp != nil; sp = sp->link) {

+	Srv *sp;

+	for(sp = srv; sp != nil; sp = sp->link) {

 		if(sp->path == qidpath || (name != nil && strcmp(sp->name, name) == 0))

 			return sp;

@@ -57,68 +38,28 @@

 	Srv *sp;

 	Qid q;

-	Fid *f;

-	ulong id;

 	if(s == DEVDOTDOT){

-		switch(NETTYPE(c->qid.path)){

-		case Qroot:

-			mkqid(&q, Qroot, 0, QTDIR);

-			devdir(c, q, "#s", 0, eve, 0555|DMDIR, dp);

-			break;

-		case Qclone:

-		default:

-			/*

-			 * Someone has walked down /srv/clone/clone/.... and

-			 * would like back up. We do not allow revisiting

-			 * previous sessions. Dead end

-			 */

-			error(Enonexist);

-			break;

-		}

+		devdir(c, c->qid, "#s", 0, eve, 0555, dp);

 		return 1;

-	id = NETID(c->qid.path);

-	if(name != nil && strcmp(name, "clone") == 0){

-		/* walk; new session */

-		qlock(&sessions);

-		id = ++sessions.path;

-		qunlock(&sessions);

-		f = smalloc(sizeof *f);

-		f->ref = 1;

-		f->nextpath = Qend;

-		mkqid(&q, NETQID(id, Qclone), id, QTDIR);

-		devdir(c, q, "clone", 0, eve, 0555|DMDIR, dp);

-		c->aux = f;

-		return 1;

-	} else if(name == nil && s == 0) {

-		/* stat, dirread; current session */

-		mkqid(&q, NETQID(id, Qclone), id, QTDIR);

-		devdir(c, q, "clone", 0, eve, 0555|DMDIR, dp);

-		return 1;

-	}

-	f = c->aux;

-	qlock(&f->lk);

+	qlock(&srvlk);

 	if(name != nil)

-		sp = srvlookup(f->tail, name, -1);

+		sp = srvlookup(name, -1);

 	else {

-		s -= 1;

-		for(sp = f->tail; sp != nil && s > 0; sp = sp->link)

+		for(sp = srv; sp != nil && s > 0; sp = sp->link)

 			s--;

 	if(sp == nil || (name != nil && (strlen(sp->name) >= sizeof(up->genbuf)))) {

-		qunlock(&f->lk);

+		qunlock(&srvlk);

 		return -1;

-	mkqid(&q, NETQID(id, sp->path), 0, QTFILE);

+	mkqid(&q, sp->path, 0, QTFILE);

 	/* make sure name string continues to exist after we release lock */

 	kstrcpy(up->genbuf, sp->name, sizeof up->genbuf);

 	devdir(c, q, up->genbuf, 0, sp->owner, sp->perm, dp);

-	qunlock(&f->lk);

+	qunlock(&srvlk);

 	return 1;

@@ -125,71 +66,19 @@

 static void

 srvinit(void)

-	global.nextpath = Qend;

+	qidpath = 1;

 static Chan*

 srvattach(char *spec)

-	Chan *c;

-	c = devattach('s', spec);

-	c->aux = &global;

-	return c;

+	return devattach('s', spec);

 static Walkqid*

 srvwalk(Chan *c, Chan *nc, char **name, int nname)

-	Walkqid *wq;

-	Fid *f;

-	int tripped;

-	/*

-	 * We need to allow for infinite recursions through clone but we

-	 * don't need to permit passing multiple clones in a single walk.

-	 * This allows us to ensure that only a single clone is alloted

-	 * per walk.

-	 */

-	tripped = 0;

-	if(nname > 1){

-		nname = 1;

-		tripped = 1;

-	}

-	wq = devwalk(c, nc, name, nname, 0, 0, srvgen);

-	if(wq == nil || wq->clone == nil || wq->clone == c)

-		return wq;

-	if(tripped){

-		/*

-		 * Our partial walk returned a newly alloc'd clone.

-		 * We wll never see a clunk for that partially walked

-		 * fid, so just clean it up now.

-		 */

-		if(NETTYPE(wq->clone->qid.path) == Qclone){

-			f = wq->clone->aux;

-			assert(f->tail == nil);

-			assert(f->ref == 1);

-			free(f);

-		}

-		/* Correct state to indicate failure to walk all names */

-		wq->clone->type = 0;

-		cclose(wq->clone);

-		wq->clone = nil;

-		return wq;

-	}

-	if(wq->clone->aux == &global)

-		return wq;

-	if(NETID(c->qid.path) != NETID(wq->clone->qid.path))

-		return wq;

-	assert(c->aux == wq->clone->aux);

-	f = c->aux;

-	qlock(&f->lk);

-	f->ref++;

-	qunlock(&f->lk);

-	return wq;

+	return devwalk(c, nc, name, nname, 0, 0, srvgen);

 static int

@@ -202,13 +91,11 @@

 srvname(Chan *c)

 	Srv *sp;

-	Fid *f;

 	char *s;

 	s = nil;

-	f = &global;

-	qlock(&f->lk);

-	for(sp = f->tail; sp != nil; sp = sp->link) {

+	qlock(&srvlk);

+	for(sp = srv; sp != nil; sp = sp->link) {

 		if(sp->chan == c){

 			s = malloc(3+strlen(sp->name)+1);

 			if(s != nil)

@@ -216,7 +103,7 @@

 			break;

-	qunlock(&f->lk);

+	qunlock(&srvlk);

 	return s;

@@ -224,7 +111,6 @@

 srvopen(Chan *c, int omode)

 	Srv *sp;

-	Fid *f;

 	Chan *nc;

 	if(c->qid.type == QTDIR){

@@ -237,14 +123,13 @@

 		c->offset = 0;

 		return c;

-	f = c->aux;

-	qlock(&f->lk);

+	qlock(&srvlk);

 	if(waserror()){

-		qunlock(&f->lk);

+		qunlock(&srvlk);

 		nexterror();

-	sp = srvlookup(f->tail, nil, c->qid.path);

+	sp = srvlookup(nil, c->qid.path);

 	if(sp == nil || sp->chan == nil)

 		error(Eshutdown);

@@ -259,7 +144,7 @@

 	nc = sp->chan;

 	incref(nc);

-	qunlock(&f->lk);

+	qunlock(&srvlk);

 	poperror();

 	cclose(c);

@@ -270,7 +155,6 @@

 srvcreate(Chan *c, char *name, int omode, ulong perm)

 	Srv *sp;

-	Fid *f;

 	if(openmode(omode) != OWRITE)

 		error(Eperm);

@@ -278,32 +162,31 @@

 	if(strlen(name) >= sizeof(up->genbuf))

 		error(Etoolong);

-	f = c->aux;

 	sp = smalloc(sizeof *sp);

 	kstrdup(&sp->name, name);

 	kstrdup(&sp->owner, up->user);

-	qlock(&f->lk);

+	qlock(&srvlk);

 	if(waserror()){

-		qunlock(&f->lk);

+		qunlock(&srvlk);

 		free(sp->owner);

 		free(sp->name);

 		free(sp);

 		nexterror();

-	if(srvlookup(f->tail, name, -1) != nil)

+	if(srvlookup(name, -1) != nil)

 		error(Eexist);

 	sp->perm = perm&0777;

-	sp->path = f->nextpath++;

+	sp->path = qidpath++;

-	c->qid.path = NETQID(NETID(c->qid.path), sp->path);

+	c->qid.path = sp->path;

 	c->qid.type = QTFILE;

-	sp->link = f->tail;

-	f->tail = sp;

+	sp->link = srv;

+	srv = sp;

-	qunlock(&f->lk);

+	qunlock(&srvlk);

 	poperror();

 	c->flag |= COPEN;

@@ -316,22 +199,18 @@

 srvremove(Chan *c)

 	Srv *sp, **l;

-	Fid *f;

-	ulong id;

 	if(c->qid.type == QTDIR)

 		error(Eperm);

-	f = c->aux;

-	qlock(&f->lk);

+	qlock(&srvlk);

 	if(waserror()){

-		qunlock(&f->lk);

+		qunlock(&srvlk);

 		nexterror();

-	l = &f->tail;

+	l = &srv;

 	for(sp = *l; sp != nil; sp = *l) {

-		if(sp->path == NETTYPE(c->qid.path))

+		if(sp->path == c->qid.path)

 			break;

 		l = &sp->link;

@@ -352,29 +231,15 @@

 	*l = sp->link;

 	sp->link = nil;

-	id = NETID(c->qid.path);

+	qunlock(&srvlk);

 	poperror();

 	if(sp->chan != nil)

 		cclose(sp->chan);

 	free(sp->owner);

 	free(sp->name);

 	free(sp);

-	if(f == &global){

-		qunlock(&f->lk);

-		return;

-	}

-	f->ref--;

-	if(f->ref == 0){

-		assert(f->tail == nil);

-		qunlock(&f->lk);

-		free(f);

-	} else if(f->ref < 0)

-		panic("srv ref rm %d id %uld", f->ref, id);

-	else

-		qunlock(&f->lk);

 static int

@@ -382,7 +247,6 @@

 	char *strs;

 	Srv *sp;

-	Fid *f;

 	Dir d;

 	if(c->qid.type & QTDIR)

@@ -397,15 +261,13 @@

 	if(n == 0)

 		error(Eshortstat);

-	f = c->aux;

-	qlock(&f->lk);

+	qlock(&srvlk);

 	if(waserror()){

-		qunlock(&f->lk);

+		qunlock(&srvlk);

 		nexterror();

-	sp = srvlookup(f->tail, nil, c->qid.path);

+	sp = srvlookup(nil, c->qid.path);

 	if(sp == nil)

 		error(Enonexist);

@@ -424,7 +286,7 @@

 	if(d.mode != ~0UL)

 		sp->perm = d.mode & 0777;

-	qunlock(&f->lk);

+	qunlock(&srvlk);

 	poperror();

 	free(strs);

@@ -436,36 +298,16 @@

 static void

 srvclose(Chan *c)

-	Fid *f;

/*

 	 * in theory we need to override any changes in removability

 	 * since open, but since all that's checked is the owner,

 	 * which is immutable, all is well.

*/

-	if((c->flag & COPEN) && (c->flag & CRCLOSE)){

+	if(c->flag & CRCLOSE){

 		if(waserror())

-			goto ref;

+			return;

 		srvremove(c);

 		poperror();

-	} else {

-ref:

-		f = c->aux;

-		if(f == &global)

-			return;

-		qlock(&f->lk);

-		f->ref--;

-		if(f->ref == 0){

-			assert(f->tail == nil);

-			qunlock(&f->lk);

-			free(f);

-		} else if(f->ref < 0)

-			panic("srvref close %d %uld", f->ref, NETID(c->qid.path));

-		else

-			qunlock(&f->lk);

@@ -480,7 +322,6 @@

 srvwrite(Chan *c, void *va, long n, vlong)

 	Srv *sp;

-	Fid *f;

 	Chan *c1;

 	int fd;

 	char buf[32];

@@ -493,17 +334,15 @@

 	c1 = fdtochan(fd, -1, 0, 1);	/* error check and inc ref */

-	f = c->aux;

-	qlock(&f->lk);

+	qlock(&srvlk);

 	if(waserror()) {

-		qunlock(&f->lk);

+		qunlock(&srvlk);

 		cclose(c1);

 		nexterror();

 	if(c1->qid.type & QTAUTH)

 		error("cannot post auth file in srv");

-	sp = srvlookup(f->tail, nil, c->qid.path);

+	sp = srvlookup(nil, c->qid.path);

 	if(sp == nil)

 		error(Enonexist);

@@ -512,7 +351,7 @@

 	sp->chan = c1;

-	qunlock(&f->lk);

+	qunlock(&srvlk);

 	poperror();

 	return n;

@@ -542,13 +381,11 @@

 srvrenameuser(char *old, char *new)

 	Srv *sp;

-	Fid *f;

-	f = &global;

-	qlock(&f->lk);

-	for(sp = f->tail; sp != nil; sp = sp->link) {

+	qlock(&srvlk);

+	for(sp = srv; sp != nil; sp = sp->link) {

 		if(sp->owner != nil && strcmp(old, sp->owner) == 0)

 			kstrdup(&sp->owner, new);

-	qunlock(&f->lk);

+	qunlock(&srvlk);