shithub: gefs

--- a/dat.h

+++ b/dat.h

@@ -272,6 +272,7 @@

 	Oclearb,	/* free block ptr if exists */

 	Oclobber,	/* remove file if it exists */

 	Owstat,		/* update kvp dirent */

+	Oretag,		/* reference a snap id */

 	Nmsgtype,	/* maximum message type */

};

--- a/fns.h

+++ b/fns.h

@@ -67,7 +67,7 @@

 void	clunkmount(Mount*);

 char*	updatesnap(Tree**, Tree*, char*);

-char*	labelsnap(Tree*, char*, int);

+char*	tagsnap(Tree*, char*, int);

 char*	delsnap(Tree*, vlong, char*);

 char*	freedl(Dlist*, int);

 Tree*	opensnap(char*, int*);

@@ -144,6 +144,7 @@

 void	dlist2kv(Dlist*, Kvp*, char*, int);

 void	lbl2kv(char*, vlong, uint, Kvp*, char*, int);

 void	link2kv(vlong, vlong, Kvp*, char*, int);

+void	retag2kv(vlong, int, int, Kvp*, char*, int);

 void	tree2kv(Tree*, Kvp*, char*, int);

 int	kv2dir(Kvp*, Xdir*);

@@ -156,7 +157,7 @@

 char*	packbp(char*, int, Bptr*);

 char*	packdkey(char*, int, vlong, char*);

 char*	packdval(char*, int, Xdir*);

-char*	packlabel(char*, int, char*);

+char*	packlbl(char*, int, char*);

 char*	packsnap(char*, int, vlong);

 char*	packsuper(char*, int, vlong);

 char*	packtree(char*, int, Tree*);

--- a/fs.c

+++ b/fs.c

@@ -73,7 +73,7 @@

 			unlock(&fs->mountlk);

 			return;

-		if((e = labelsnap(t, a->new, a->mutable)) != nil){

+		if((e = tagsnap(t, a->new, a->mutable)) != nil){

 			fprint(a->fd, "snap: error creating '%s': %s\n", a->new, e);

 			unlock(&fs->mountlk);

 			return;

--- a/pack.c

+++ b/pack.c

@@ -398,6 +398,21 @@

 void

+retag2kv(vlong gen, int dlbl, int dsucc, Kvp *kv, char *buf, int nbuf)

+{

+	char *p;

+	kv->k = buf;

+	if((p = packsnap(buf, nbuf, gen)) == nil)

+		abort();

+	kv->nk = p - buf;

+	kv->v = p;

+	p[0] = dlbl;

+	p[1] = dsucc;

+	kv->nv = 2;

+}

+void

 link2kv(vlong gen, vlong succ, Kvp *kv, char *buf, int nbuf)

 	char *p;

@@ -450,7 +465,7 @@

 char*

-packlabel(char *p, int sz, char *name)

+packlbl(char *p, int sz, char *name)

 	int n;

--- a/ream.c

+++ b/ream.c

@@ -140,7 +140,7 @@

 	t.nlbl = 1;

 	t.ht = 1;

 	t.gen = fs->nextgen++;

-	t.prev = -1ULL;

+	t.prev = 0;

 	t.bp = a->bp;

 	p = packtree(p, e - p, &t);

 	kv.nv = p - kv.v;

@@ -155,11 +155,11 @@

 	kv.nk = p - kv.k;

 	kv.v = p;

 	memset(&t, 0, sizeof(Tree));

-	t.nsucc = 1;

+	t.nsucc = 0;

 	t.nlbl = 1;

 	t.ht = 1;

 	t.gen = fs->nextgen++;

-	t.prev = -1ULL;

+	t.prev = 0;

 	t.bp = r->bp;

 	p = packtree(p, e - p, &t);

 	kv.nv = p - kv.v;

--- a/snap.c

+++ b/snap.c

@@ -321,7 +321,7 @@

 		m[nm].op = Odelete;

 		m[nm].k = buf[nm];

-		if((e = packlabel(buf[nm], sizeof(buf[nm]), name)) == nil)

+		if((e = packlbl(buf[nm], sizeof(buf[nm]), name)) == nil)

 			return Ename;

 		m[nm].nk = e - m[nm].k;

 		m[nm].v = nil;

@@ -359,7 +359,7 @@

  * will show up in the dump.

*/

 char*

-labelsnap(Tree *t, char *name, int mutable)

+tagsnap(Tree *t, char *name, int mutable)

 	char buf[3][Kvmax];

 	Msg m[3];

@@ -381,31 +381,23 @@

 		n->nsucc = 0;

 		n->ht = t->ht;

 		n->bp = t->bp;

-		n->prev = t->gen;

+		n->prev = t->prev;

 		n->base = t->gen;

 		n->gen = aincv(&fs->nextgen, 1);

 		n->memgen = aincv(&fs->nextgen, 1);

-		t->flag |= Tforked;

-		t->nsucc++;

-		m[i].op = Oinsert;

-		tree2kv(t, &m[i], buf[i], sizeof(buf[i]));

+		m[i].op = Oretag;

+		retag2kv(t->gen, 0, 1, &m[i], buf[i], sizeof(buf[i]));

 		i++;

 		m[i].op = Oinsert;

-		tree2kv(n, &m[i], buf[i], sizeof(buf[i]));

-		i++;

-		m[i].op = Oinsert;

 		lbl2kv(name, n->gen, 1, &m[i], buf[i], sizeof(buf[i]));

 		i++;

 	}else{

 		t->nlbl++;

-		m[i].op = Oinsert;

-		tree2kv(t, &m[i], buf[i], sizeof(buf[i]));

-		i++;

+		m[i].op = Oretag;

+		retag2kv(t->gen, 1, 0, &m[i], buf[i], sizeof(buf[i]));

+		i++;

 		m[i].op = Oinsert;

 		lbl2kv(name, t->gen, 0, &m[i], buf[i], sizeof(buf[i]));

 		i++;

@@ -426,15 +418,15 @@

 	char buf[4][Kvmax], *e;

 	Msg m[4];

 	Tree *t;

+	int i;

 	if(!o->dirty)

 		return nil;

 	/* update the old kvp */

-	o->nsucc++;

+	o->gen, o->nsucc, o->nlbl, o->bp);

 	o->nlbl--;

-	m[0].op = Oinsert;

-	tree2kv(o, &m[0], buf[0], sizeof(buf[0]));

+	o->nsucc++;

 	/* create the new one */

@@ -448,17 +440,31 @@

 	t->ht = o->ht;

 	t->bp = o->bp;

 	t->base = o->base;

-	t->prev = o->gen;

+	if(o->nlbl == 0 && o->nsucc == 1)

+		t->prev = o->prev;

+	else

+		t->prev = o->gen;

 	t->gen = o->memgen;

 	t->memgen = aincv(&fs->nextgen, 1);

-	m[1].op = Oinsert;

-	tree2kv(t, &m[1], buf[1], sizeof(buf[1]));

-	m[2].op = Oinsert;

-	link2kv(t->prev, t->gen, &m[2], buf[2], sizeof(buf[2]));

-	m[3].op = Oinsert;

-	lbl2kv(lbl, t->gen, Lmut, &m[3], buf[3], sizeof(buf[3]));

-	if((e = btupsert(&fs->snap, m, 4)) != nil){

+	i = 0;

+	m[i].op = Oretag;

+	retag2kv(o->gen, -1, 1, &m[i], buf[i], sizeof(buf[i]));

+	i++;

+	m[i].op = Oinsert;

+	tree2kv(t, &m[i], buf[i], sizeof(buf[i]));

+	i++;

+	m[i].op = Oinsert;

+	link2kv(t->prev, t->gen, &m[i], buf[i], sizeof(buf[i]));

+	i++;

+	m[i].op = Oinsert;

+	lbl2kv(lbl, t->gen, Lmut, &m[i], buf[i], sizeof(buf[i]));

+	i++;

+	if((e = btupsert(&fs->snap, m, i)) != nil){

 		free(t);

 		return e;

@@ -467,10 +473,8 @@

 	o->dirty = 0;

 	/* this was the last ref to the snap */

-	if(o->nlbl == 0 && o->nsucc == 1){

-		t->prev = o->prev;

+	if(o->nlbl == 0 && o->nsucc == 1)

 		delsnap(o, -1, nil);

-	}

 	closesnap(o);

 	asetp(r, t);

 	return nil;

@@ -490,7 +494,7 @@

 	Key k;

 	/* Klabel{"name"} => Ksnap{id} */

-	if((p = packlabel(buf, sizeof(buf), label)) == nil)

+	if((p = packlbl(buf, sizeof(buf), label)) == nil)

 		return nil;

 	k.k = buf;

 	k.nk = p - buf;

--- a/tree.c

+++ b/tree.c

@@ -400,6 +400,8 @@

 static int

 apply(Kvp *kv, Msg *m, char *buf, int nbuf)

+	Tree t;

 	switch(m->op){

 	case Oclearb:

 	case Odelete:

@@ -412,6 +414,13 @@

 	case Owstat:

 		assert(keycmp(kv, m) == 0);

 		statupdate(kv, m);

+		return 1;

+	case Oretag:

+		assert(m->nv == 2);

+		unpacktree(&t, kv->v, kv->nv);

+		t.nlbl += m->v[0];

+		t.nsucc += m->v[1];

+		packtree(kv->v, kv->nv, &t);

 		return 1;

 	default:

 		abort();