.

wcfs/pptreesubset.go

@@ -105,24 +105,95 @@ func (S PPTreeSubSet) verify() {
 	}
 }
 
-// DifferenceInplace sets A = PP(A.leafs \ B.leafs)
+// Path returns path leading to node specified by oid.
 //
-// In other words it removes B nodes from A while still maintaining A as P-connected.
-func (A PPTreeSubSet) DifferenceInplace(B PPTreeSubSet) {
-	if debugPPSet {
-		fmt.Printf("\n\nDifferenceInplace:\n")
-		fmt.Printf("  A: %s\n", A)
-		fmt.Printf("  B: %s\n", B)
-		defer fmt.Printf("->D: %s\n", A)
+// The node must be in the set.
+func (S PPTreeSubSet) Path(oid zodb.Oid) (path []zodb.Oid) {
+	for {
+		t, ok := S[oid]
+		if !ok {
+			panicf("node %s is not in the set  <- %v", oid, path)
 		}
 
-	A.verify()
-	B.verify()
-	defer A.verify()
+		path = append([]zodb.Oid{oid}, path...)
+		oid = t.parent
 
-	A.xDifferenceInplace(B)
+		if oid == zodb.InvalidOid {
+			break
+		}
+	}
+
+	return path
+}
+
+// XXX doc
+func (S PPTreeSubSet) AddNodePath(path []Node) { // XXX Tree|Bucket; path[0] = root
+	// XXX assert Tree Tree ... Tree Bucket
+//	root := path[0].(*Tree).POid()
+
+	oidv := []zodb.Oid{}
+	for _, node := range path {
+		oidv = append(oidv, node.POid())
+	}
+	S.AddPath(oidv)
+}
+
+// XXX doc
+func (S PPTreeSubSet) AddPath(path []zodb.Oid) {
+	S.verify()
+	defer S.verify()
+
+	l := len(path)
+	if l == 0 {
+		panic("empty path")
+	}
+
+	// don't explicitly keep track of embedded buckets - they all have
+	// InvalidOid, and thus, if kept in S, e.g. T/B1:a and another
+	// T/B2:b would lead to InvalidOid having multiple parents.
+	if l >= 2 && path[l-1] == zodb.InvalidOid {
+		path = path[:l-1]
+	}
+
+	parent := zodb.InvalidOid
+	var ptrack   *nodeInTree = nil
+	var track    *nodeInTree	// XXX kill here
+	var oldTrack bool
+	for _, oid := range path {
+		if oid == zodb.InvalidOid {
+			panicf("path has node with invalid oid: %v", path)
+		}
+
+		track, oldTrack = S[oid]
+		if !oldTrack {
+			track = &nodeInTree{parent: parent, nchild: 0} // XXX
+			/*
+			if i == l-1 { // leaf
+				track.holes = SetKey{}
+			}
+			*/
+			S[oid] = track
+			// XXX .trackNew += oid
+		}
+		if track.parent != parent {
+			// XXX -> error (e.g. due to corrupt data in ZODB)
+			panicf("node %s is reachable from multiple parents: %s %s",
+				oid, track.parent, parent)
+		}
+
+		if ptrack != nil && !oldTrack {
+			ptrack.nchild++
+		}
+
+		parent = oid
+		ptrack = track
+	}
 }
 
+
+
+// ---- Union/Difference ----
+
 // UnionInplace sets A = PP(A.leafs | B.leafs)
 //
 // In other words it adds B nodes to A.
@@ -141,28 +212,44 @@ func (A PPTreeSubSet) UnionInplace(B PPTreeSubSet) {
 	A.xUnionInplace(B)
 }
 
+// DifferenceInplace sets A = PP(A.leafs \ B.leafs)
+//
+// In other words it removes B nodes from A while still maintaining A as P-connected.
+func (A PPTreeSubSet) DifferenceInplace(B PPTreeSubSet) {
+	if debugPPSet {
+		fmt.Printf("\n\nDifferenceInplace:\n")
+		fmt.Printf("  A: %s\n", A)
+		fmt.Printf("  B: %s\n", B)
+		defer fmt.Printf("->D: %s\n", A)
+	}
 
-func (A PPTreeSubSet) xDifferenceInplace(B PPTreeSubSet) {
+	A.verify()
+	B.verify()
+	defer A.verify()
+
+	A.xDifferenceInplace(B)
+}
+
+func (A PPTreeSubSet) xUnionInplace(B PPTreeSubSet) {
 	if debugPPSet {
-		fmt.Printf("\n\n  xDifferenceInplace:\n")
+		fmt.Printf("\n\n  xUnionInplace:\n")
 		fmt.Printf("    a: %s\n", A)
 		fmt.Printf("    b: %s\n", B)
-		defer fmt.Printf("  ->d: %s\n", A)
+		defer fmt.Printf("  ->u: %s\n", A)
 	}
 
 	δnchild := map[zodb.Oid]int{}
 
-	// remove B.leafs and their parents
 	for oid, t2 := range B {
-		if t2.nchild != 0 {
-			continue // not a leaf
-		}
-
-		t, present := A[oid]
-		if !present {
-			continue // already not there
+		t, already := A[oid]
+		if !already {
+			t = &nodeInTree{parent: t2.parent, nchild: 0}
+			A[oid] = t
+			// remember to nchild++ in parent
+			if t.parent != zodb.InvalidOid {
+				δnchild[t.parent] += 1
 			}
-
+		} else {
 			if t2.parent != t.parent {
 				// XXX or verify this at Track time and require
 				// that update is passed only entries with the
@@ -171,36 +258,33 @@ func (A PPTreeSubSet) xDifferenceInplace(B PPTreeSubSet) {
 				panicf("node %s is reachable from multiple parents: %s %s",
 					oid, t.parent, t2.parent)
 			}
-
-		delete(A, oid)
-		if t.parent != zodb.InvalidOid {
-			δnchild[t.parent] -= 1
 		}
 	}
 
 	A.fixup(δnchild)
 }
 
-func (A PPTreeSubSet) xUnionInplace(B PPTreeSubSet) {
+func (A PPTreeSubSet) xDifferenceInplace(B PPTreeSubSet) {
 	if debugPPSet {
-		fmt.Printf("\n\n  xUnionInplace:\n")
+		fmt.Printf("\n\n  xDifferenceInplace:\n")
 		fmt.Printf("    a: %s\n", A)
 		fmt.Printf("    b: %s\n", B)
-		defer fmt.Printf("  ->u: %s\n", A)
+		defer fmt.Printf("  ->d: %s\n", A)
 	}
 
 	δnchild := map[zodb.Oid]int{}
 
+	// remove B.leafs and their parents
 	for oid, t2 := range B {
-		t, already := A[oid]
-		if !already {
-			t = &nodeInTree{parent: t2.parent, nchild: 0}
-			A[oid] = t
-			// remember to nchild++ in parent
-			if t.parent != zodb.InvalidOid {
-				δnchild[t.parent] += 1
+		if t2.nchild != 0 {
+			continue // not a leaf
 		}
-		} else {
+
+		t, present := A[oid]
+		if !present {
+			continue // already not there
+		}
+
 		if t2.parent != t.parent {
 			// XXX or verify this at Track time and require
 			// that update is passed only entries with the
@@ -209,6 +293,10 @@ func (A PPTreeSubSet) xUnionInplace(B PPTreeSubSet) {
 			panicf("node %s is reachable from multiple parents: %s %s",
 				oid, t.parent, t2.parent)
 		}
+
+		delete(A, oid)
+		if t.parent != zodb.InvalidOid {
+			δnchild[t.parent] -= 1
 		}
 	}
 
@@ -259,92 +347,6 @@ func (S PPTreeSubSet) gc1(oid zodb.Oid) {
 }
 
 
-// Path returns path leading to node specified by oid.
-//
-// The node must be in the set.
-func (S PPTreeSubSet) Path(oid zodb.Oid) (path []zodb.Oid) {
-	for {
-		t, ok := S[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 doc
-func (S PPTreeSubSet) AddNodePath(path []Node) { // XXX Tree|Bucket; path[0] = root
-	// XXX assert Tree Tree ... Tree Bucket
-//	root := path[0].(*Tree).POid()
-
-	oidv := []zodb.Oid{}
-	for _, node := range path {
-		oidv = append(oidv, node.POid())
-	}
-	S.AddPath(oidv)
-}
-
-// XXX doc
-func (S PPTreeSubSet) AddPath(path []zodb.Oid) {
-	S.verify()
-	defer S.verify()
-
-	l := len(path)
-	if l == 0 {
-		panic("empty path")
-	}
-
-	// don't explicitly keep track of embedded buckets - they all have
-	// InvalidOid, and thus, if kept in S, e.g. T/B1:a and another
-	// T/B2:b would lead to InvalidOid having multiple parents.
-	if l >= 2 && path[l-1] == zodb.InvalidOid {
-		path = path[:l-1]
-	}
-
-	parent := zodb.InvalidOid
-	var ptrack   *nodeInTree = nil
-	var track    *nodeInTree	// XXX kill here
-	var oldTrack bool
-	for _, oid := range path {
-		if oid == zodb.InvalidOid {
-			panicf("path has node with invalid oid: %v", path)
-		}
-
-		track, oldTrack = S[oid]
-		if !oldTrack {
-			track = &nodeInTree{parent: parent, nchild: 0} // XXX
-			/*
-			if i == l-1 { // leaf
-				track.holes = SetKey{}
-			}
-			*/
-			S[oid] = track
-			// XXX .trackNew += oid
-		}
-		if track.parent != parent {
-			// XXX -> error (e.g. due to corrupt data in ZODB)
-			panicf("node %s is reachable from multiple parents: %s %s",
-				oid, track.parent, parent)
-		}
-
-		if ptrack != nil && !oldTrack {
-			ptrack.nchild++
-		}
-
-		parent = oid
-		ptrack = track
-	}
-}
-
-
 // Clone returns copy of the set.
 // XXX place
 func (orig PPTreeSubSet) Clone() PPTreeSubSet {