.

wcfs/δbtail.go

@@ -218,7 +218,8 @@ type ΔTree struct {
 
 
 // XXX is a set of PP(leafs) nodes	XXX -> PTreeSubSet ? TreePSubSet ?  TreePPSet ? PPSubSet ?
-//					XXX    PPNodeSet? TreePPSubSet ?
+//					XXX    PPNodeSet? TreePPSubSet ? PPSet? PPNodeSet? PPOidSet?
+//					~~ PPOidSet ~~ <- Y
 //
 // where PP maps a leaf to {leaf, leaf.parent, leaf.parent.parent, ...} up to
 // top root node from where the leaf is reached.
@@ -228,7 +229,7 @@ type ΔTree struct {
 // XXX place
 type trackIndex map[zodb.Oid]*nodeTrack
 
-// XXX place				XXX PTreeSubSetNode ?
+// XXX place				XXX PTreeSubSetNode ? PPNode? nodeP? nodePnC ?
 // nodeTrack represents tracking information about a node.
 type nodeTrack struct {
 	parent  zodb.Oid // parent node | InvalidOid for root
@@ -239,15 +240,20 @@ type nodeTrack struct {
 */
 }
 
-// δtrackIndex represents change to trackIndex.
+// δtrackIndex represents change to trackIndex.		XXX name
+//
+// The result B of applying δ to A is:
+//
+//	B = A.Difference(δ.Del).Union(δ.Add)
 // XXX place
 type δtrackIndex struct {
+/*
 	// set of leaf nodes to remove. After leafs are removed, their parents
 	// are automatically cleaned down-up. Removals are processed before
 	// adds (see below).
 	DelLeaf SetOid
-
-	// nodes to add		XXX -> add/modify ?
+*/
+	Del trackIndex
 	Add trackIndex
 }
 
@@ -326,82 +332,40 @@ func (tidx trackIndex) verify() {
 //
 // In other words it removes B nodes from A while still maintaining A as P-connected.
 func (A trackIndex) DifferenceInplace(B trackIndex) {
-	//fmt.Printf("\n\nDifferenceInplace:\n")
-	//fmt.Printf("A: %s\n", A)
-	//fmt.Printf("B: %s\n", B)
+	fmt.Printf("\n\nDifferenceInplace:\n")
+	fmt.Printf("  A: %s\n", A)
+	fmt.Printf("  B: %s\n", B)
+	defer fmt.Printf("->D: %s\n", A)
 
 	A.verify()
 	B.verify()
 	defer A.verify()
-	panic("TODO")
-}
 
-// UnionInplace sets A = PP(A.leafs | B.leafs)
-//
-// In other words it adds B nodes to A.
-func (A trackIndex) UnionInplace(B trackIndex) {
-	//fmt.Printf("\n\nUnionInplace:\n")
-	//fmt.Printf("A: %s\n", A)
-	//fmt.Printf("B: %s\n", B)
-
-	A.verify()
-	B.verify()
-	defer A.verify()
+	δnchild := map[zodb.Oid]int{}
 
+	// remove B.leafs and thier parents
 	for oid, t2 := range B {
-		t, already := A[oid]
-		if !already {
-			t = &nodeTrack{parent: t2.parent, nchild: t2.nchild}
-			A[oid] = t
-		} else {
-			if t2.parent != t.parent {
-				// XXX or verify this at Track time and require
-				// that update is passed only entries with the
-				// same .parent? (then it would be ok to panic here)
-				// XXX -> error (e.g. due to corrupt data in ZODB)
-				panicf("node %s is reachable from multiple parents: %s %s",
-					oid, t.parent, t2.parent)
-			}
-
-			t.nchild += t2.nchild
-
-			if t.parent != zodb.InvalidOid {
-				// this node is already present in both trees
-				// compensate for that in its parent (which must be present)
-				A[t.parent].nchild--
-			}
+		if t2.nchild != 0 {
+			continue // not a leaf
 		}
-	}
-}
-
-// ApplyΔ applies δ to trackIdx.	XXX
-func (tidx trackIndex) ApplyΔ(δ *δtrackIndex) {
-	//fmt.Printf("\n\nApplyΔ\n")
-	//fmt.Printf("\ttidx:    %v\n", tidx)
-	//fmt.Printf("\tDelLeaf: %v\n", δ.DelLeaf)
-	//fmt.Printf("\tAdd:     %v\n", δ.Add)
-	//defer fmt.Printf("\n\t-> tidx: %v\n", tidx)
-
-	tidx.verify()
 
-	δnchild := map[zodb.Oid]int{}
-
-	// remove leafs and thier parents
-	for leaf := range δ.DelLeaf {
-		t, present := tidx[leaf]
+		t, present := A[oid]
 		if !present {
 			continue // already not there
 		}
 
-		delete(tidx, leaf)
+		// XXX assert t.parent == t2.parent ?
+
+		delete(A, oid)
 		if t.parent != zodb.InvalidOid {
 			δnchild[t.parent] -= 1
 		}
 	}
 
+/* XXX kill
 	// process adds
 	for oid, δt := range δ.Add {
-		t, already := tidx[oid]
+		t, already := A[oid]
 		if already {
 			if t.parent != zodb.InvalidOid {
 				δnchild[t.parent] -= 1
@@ -409,18 +373,19 @@ func (tidx trackIndex) ApplyΔ(δ *δtrackIndex) {
 			}
 		} else {
 			t = &nodeTrack{parent: δt.parent, nchild: 0}
-			tidx[oid] = t
+			A[oid] = t
 		}
 
 		if t.parent != zodb.InvalidOid {
 			δnchild[t.parent] += 1 // remeber to nchild++ in parent
 		}
 	}
+*/
 
 	// perform scheduled δnchild adjustment
 	gcq := []zodb.Oid{}
 	for oid, δnc := range δnchild {
-		t := tidx[oid]	// XXX t can be nil -> XXX no must be there as tidx is connected
+		t := A[oid]	// XXX t can be nil -> XXX no must be there as A is connected
 		t.nchild += δnc
 		if t.nchild == 0 && /* not root node */t.parent != zodb.InvalidOid {
 			gcq = append(gcq, oid)
@@ -429,10 +394,64 @@ func (tidx trackIndex) ApplyΔ(δ *δtrackIndex) {
 
 	// GC parents that became to have .nchild == 0
 	for _, oid := range gcq {
-		tidx.gc1(oid)
+		A.gc1(oid)
 	}
+}
+
+// UnionInplace sets A = PP(A.leafs | B.leafs)
+//
+// In other words it adds B nodes to A.
+func (A trackIndex) UnionInplace(B trackIndex) {
+	fmt.Printf("\n\nUnionInplace:\n")
+	fmt.Printf("  A: %s\n", A)
+	fmt.Printf("  B: %s\n", B)
+	defer fmt.Printf("->U: %s\n", A)
+
+	A.verify()
+	B.verify()
+	defer A.verify()
+
+	for oid, t2 := range B {
+		t, already := A[oid]
+		if !already {
+			t = &nodeTrack{parent: t2.parent, nchild: t2.nchild}
+			A[oid] = t
+		} else {
+			if t2.parent != t.parent {
+				// XXX or verify this at Track time and require
+				// that update is passed only entries with the
+				// same .parent? (then it would be ok to panic here)
+				// XXX -> error (e.g. due to corrupt data in ZODB)
+				panicf("node %s is reachable from multiple parents: %s %s",
+					oid, t.parent, t2.parent)
+			}
+
+			t.nchild += t2.nchild
+
+			if t.parent != zodb.InvalidOid {
+				// this node is already present in both trees
+				// compensate for that in its parent (which must be present)
+				A[t.parent].nchild--
+			}
+		}
+	}
+}
+
+// ApplyΔ applies δ to trackIdx.	XXX
+func (tidx trackIndex) ApplyΔ(δ *δtrackIndex) {
+	fmt.Printf("\n\nApplyΔ\n")
+	fmt.Printf("  A: %s\n", tidx)
+	fmt.Printf("  -: %s\n", δ.Del)
+	fmt.Printf("  +: %s\n", δ.Add)
+	defer fmt.Printf("\n->B: %s\n", tidx)
 
 	tidx.verify()
+	δ.Del.verify()
+	δ.Add.verify()
+	defer tidx.verify()
+
+	tidx.DifferenceInplace(δ.Del)
+	tidx.UnionInplace(δ.Add)
 }
 
 // treeSetKey represents ordered set of keys.
@@ -601,6 +620,28 @@ func (δBtail *ΔBtail) holeIdxFor(root zodb.Oid) treeSetKey {
 	return holeIdx
 }
 
+// Path returns path leading to node speficied by oid.
+//
+// The node must be in the set.
+// XXX place
+func (tidx trackIndex) Path(oid zodb.Oid) (path []zodb.Oid) {
+	for {
+		t, ok := tidx[oid]
+		if !ok {
+			panicf("node %s is not in the set  <- %v", oid, path)
+		}
+
+		path = append([]zodb.Oid{oid}, path...)
+		oid = t.parent
+
+		if oid == zodb.InvalidOid {
+			break
+		}
+	}
+
+	return path
+}
+
 // XXX place
 // XXX doc
 func (tidx trackIndex) AddNodePath(path []Node) { // XXX Tree|Bucket; path[0] = root
@@ -615,6 +656,9 @@ func (tidx trackIndex) AddNodePath(path []Node) { // XXX Tree|Bucket; path[0] =
 }
 
 func (tidx trackIndex) AddPath(path []zodb.Oid) {
+	tidx.verify()
+	defer tidx.verify()
+
 	l := len(path)
 	if l == 0 {
 		panic("empty path")
@@ -1140,6 +1184,7 @@ func treediff(ctx context.Context, root zodb.Oid, δtops SetOid, δZTC SetOid, t
 	}
 
 	// adjust trackIdx by merge(δtrackTops)
+/*
 	δtrack := &δtrackIndex{DelLeaf: SetOid{}, Add: trackIndex{}}
 	for _, δ := range δtrackv {
 		δtrack.DelLeaf.Update(δ.DelLeaf)
@@ -1147,6 +1192,12 @@ func treediff(ctx context.Context, root zodb.Oid, δtops SetOid, δZTC SetOid, t
 			δtrack.Add[oid] = t // XXX verify changes from 2 δtrackTops are consistent
 		}
 	}
+*/
+	δtrack := &δtrackIndex{Del: trackIndex{}, Add: trackIndex{}}
+	for _, δ := range δtrackv {
+		δtrack.Del.UnionInplace(δ.Del)
+		δtrack.Add.UnionInplace(δ.Add)
+	}
 	trackIdx.ApplyΔ(δtrack)
 
 	return δT, nil
@@ -1221,7 +1272,8 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx trackIndex, h
 	if B == nil { panic("B is nil") }
 
 	δ = map[Key]ΔValue{}
-	δtrack = &δtrackIndex{DelLeaf: SetOid{}, Add: trackIndex{}}
+//	δtrack = &δtrackIndex{DelLeaf: SetOid{}, Add: trackIndex{}}
+	δtrack = &δtrackIndex{Del: trackIndex{}, Add: trackIndex{}}
 	defer tracef("  -> δ: %v\n", δ)
 
 	// path prefix to A and B
@@ -1261,7 +1313,9 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx trackIndex, h
 	// XXX
 	// XXX requires A.oid == B.oid
 	// XXX -> trackIndex
-	BtrackIdx := map[zodb.Oid]nodeTrack{B.POid(): nodeTrack{parent: trackIdx[B.POid()].parent}}
+//	BtrackIdx := map[zodb.Oid]nodeTrack{B.POid(): nodeTrack{parent: trackIdx[B.POid()].parent}}
+	BtrackIdx := trackIndex{}
+	BtrackIdx.AddPath(trackIdx.Path(B.POid()))
 
 	// phase 1: expand A top->down driven by δZTC.
 	// by default a node contributes to δ-
@@ -1284,7 +1338,8 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx trackIndex, h
 			// a is bucket -> δ-
 			δA, err := diffB(ctx, a, nil);  /*X*/if err != nil { return nil,nil, err }
 			err = δMerge(δ, δA);		/*X*/if err != nil { return nil,nil, err }
-			δtrack.DelLeaf.Add(a.POid())
+//			δtrack.DelLeaf.Add(a.POid())
+			δtrack.Del.AddPath(ra.Path())
 
 			// Bkqueue <- δA
 			for k := range δA {
@@ -1341,7 +1396,8 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx trackIndex, h
 							bchildren := Bv.Expand(blo)
 							for _, bc := range bchildren {
 									bcOid := bc.node.POid()
-									BtrackIdx[bcOid] = nodeTrack{parent: blo.node.POid()}
+//									BtrackIdx[bcOid] = nodeTrack{parent: blo.node.POid()}
+									BtrackIdx.AddPath(bc.Path())
 									if acOid == bcOid {
 										found = true
 									}
@@ -1356,6 +1412,14 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx trackIndex, h
 						// XXX Bkqueue <- holes(ac.range \ bc.range)	XXX test for this
 
 						// adjust trackIdx since path to the node could have changed
+						apath := trackIdx.Path(acOid)
+						bpath := BtrackIdx.Path(acOid)
+						if !reflect.DeepEqual(apath, bpath) {
+							δtrack.Del.AddPath(apath)
+							δtrack.Add.AddPath(bpath)
+						}
+
+						/* XXX kill
 						oid := acOid
 						for oid != zodb.InvalidOid {
 							told := trackIdx[oid]
@@ -1364,11 +1428,12 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx trackIndex, h
 								break
 							}
 							if told == nil || (told.parent != tnew.parent) {
-								δtrack.Add[oid] = &tnew // XXX adjust nchildren
+								δtrack.Add.AddPath(BtrackIdx.Path(oid))
 							}
 
 							oid = tnew.parent
 						}
+						*/
 
 						continue
 					}
@@ -1453,7 +1518,8 @@ func diffT(ctx context.Context, A, B *Tree, δZTC SetOid, trackIdx trackIndex, h
 
 				// δ <- δA
 				err = δMerge(δ, δA);	/*X*/if err != nil { return nil,nil, err }
-				δtrack.DelLeaf.Add(a.node.POid())
+//				δtrack.DelLeaf.Add(a.node.POid())
+				δtrack.Del.AddPath(a.Path())
 
 				// Bkqueue <- δA
 				for k_ := range δA {