.

wcfs/internal/set/set.go

@@ -20,6 +20,7 @@
 package set
 
 //go:generate ./gen-set set I64 int64  zset_i64.go
+//go:generate ./gen-set set Str string zset_str.go
 //go:generate ./gen-set set Oid _Oid   zset_oid.go
 //go:generate ./gen-set set Tid _Tid   zset_tid.go
 

wcfs/internal/set/zset_str.go

+// Code generated by gen-set Str string; DO NOT EDIT.
+
+// Copyright (C) 2015-2021  Nexedi SA and Contributors.
+//                          Kirill Smelkov <kirr@nexedi.com>
+//
+// This program is free software: you can Use, Study, Modify and Redistribute
+// it under the terms of the GNU General Public License version 3, or (at your
+// option) any later version, as published by the Free Software Foundation.
+//
+// You can also Link and Combine this program with other software covered by
+// the terms of any of the Free Software licenses or any of the Open Source
+// Initiative approved licenses and Convey the resulting work. Corresponding
+// source of such a combination shall include the source code for all other
+// software used.
+//
+// This program is distributed WITHOUT ANY WARRANTY; without even the implied
+// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+//
+// See COPYING file for full licensing terms.
+// See https://www.nexedi.com/licensing for rationale and options.
+
+package set
+
+import (
+	"fmt"
+	"sort"
+	"strings"
+)
+
+// SetStr is a set of string.
+type SetStr map[string]struct{}
+
+// Add adds v to the set.
+func (s SetStr) Add(v string) {
+	s[v] = struct{}{}
+}
+
+// Del removes v from the set.
+// it is noop if v was not in the set.
+func (s SetStr) Del(v string) {
+	delete(s, v)
+}
+
+// Has checks whether the set contains v.
+func (s SetStr) Has(v string) bool {
+	_, ok := s[v]
+	return ok
+}
+
+// Update adds t values to s.
+func (s SetStr) Update(t SetStr) {
+	for v := range t {
+		s.Add(v)
+	}
+}
+
+// Elements returns all elements of set as slice.
+func (s SetStr) Elements() []string {
+	ev := make([]string, len(s))
+	i := 0
+	for e := range s {
+		ev[i] = e
+		i++
+	}
+	return ev
+}
+
+// Union returns s ∪ t
+func (s SetStr) Union(t SetStr) SetStr {
+	// l = max(len(s), len(t))
+	l := len(s)
+	if lt := len(t); lt > l {
+		l = lt
+	}
+
+	u := make(SetStr, l)
+
+	for v := range s {
+		u.Add(v)
+	}
+	for v := range t {
+		u.Add(v)
+	}
+	return u
+}
+
+// Intersection returns s ∩ t
+func (s SetStr) Intersection(t SetStr) SetStr {
+	i := SetStr{}
+	for v := range s {
+		if t.Has(v) {
+			i.Add(v)
+		}
+	}
+	return i
+}
+
+// Difference returns s\t.
+func (s SetStr) Difference(t SetStr) SetStr {
+	d := SetStr{}
+	for v := range s {
+		if !t.Has(v) {
+			d.Add(v)
+		}
+	}
+	return d
+}
+
+// SymmetricDifference returns s Δ t.
+func (s SetStr) SymmetricDifference(t SetStr) SetStr {
+	d := SetStr{}
+	for v := range s {
+		if !t.Has(v) {
+			d.Add(v)
+		}
+	}
+	for v := range t {
+		if !s.Has(v) {
+			d.Add(v)
+		}
+	}
+	return d
+}
+
+// Equal returns whether a == b.
+func (a SetStr) Equal(b SetStr) bool {
+	if len(a) != len(b) {
+		return false
+	}
+
+	for v := range a {
+		_, ok := b[v]
+		if !ok {
+			return false
+		}
+	}
+
+	return true
+}
+
+// Clone returns copy of the set.
+func (orig SetStr) Clone() SetStr {
+	klon := make(SetStr, len(orig))
+	for v := range orig {
+		klon.Add(v)
+	}
+	return klon
+}
+
+// --------
+
+func (s SetStr) SortedElements() []string {
+	ev := s.Elements()
+	sort.Slice(ev, func(i, j int) bool {
+		return ev[i] < ev[j]
+	})
+	return ev
+}
+
+func (s SetStr) String() string {
+	ev := s.SortedElements()
+	strv := make([]string, len(ev))
+	for i, v := range ev {
+		strv[i] = fmt.Sprintf("%v", v)
+	}
+	return "{" + strings.Join(strv, " ") + "}"
+}

wcfs/internal/zdata/δftail.go

@@ -103,8 +103,8 @@ type ΔF struct {
 // ΔFile represents a change to one file.
 type ΔFile struct {
 	Rev    zodb.Tid
-	Blocks SetI64 // changed blocks
-	Size   bool   // whether file size changed
+	Blocks SetI64 // changed blocks			XXX -> ΔBlocks ?
+	Size   bool   // whether file size changed	XXX -> ΔSize?
 }
 
 // zblkInΔFtail is ΔFtail-related volatile data embedded into ZBlk*.

wcfs/internal/zdata/δftail_test.go

@@ -21,9 +21,85 @@ package zdata
 
 import (
 	"testing"
+
+	"lab.nexedi.com/kirr/neo/go/zodb"
+
+	"lab.nexedi.com/nexedi/wendelin.core/wcfs/internal/set"
 )
 
+type SetStr = set.SetStr
+
+// ΔFTestEntry represents one entry in ΔFtail tests.
+type ΔFTestEntry struct {
+	δblkTab  map[int64]string  // change in tree part {} #blk -> ZBlk<oid>
+	δblkData SetStr            // change to ZBlk objects
+}
+
 func TestΔFtail(t *testing.T) {
+	// δT is shorthand to create δblkTab.
+	type δT = map[int64]string
+
+	// δD is shorthand to create δblkData.
+	δD := func(zblkv ...string) SetStr {
+		δ := SetStr{}
+		for _, zblk := range zblkv {
+			δ.Add(zblk)
+		}
+		return δ
+	}
+
+	const a, b, c, ø = "a", "b", "c", "ø"
+
+	testv := []ΔFTestEntry{
+		{δT{1:a,2:b,3:ø},	δD(a)},
+		{δT{},			δD(c)},
+		{δT{2:c},		δD(a,b)},
+	}
+
+	vδf    := []ΔFile{}           // (rev↑, {}blk)		XXX +.Size?
+	blkTab := map[int64]string{}  // #blk -> ZBlk<oid>
+	Zinblk := map[string]SetI64{} // ZBlk<oid> -> which #blk refer to it
+	for _, test := range testv {
+		δf := SetI64{}
+
+		for blk, zblk := range test.δblkTab {
+			// rebuild blkTab/Zinblk
+			zprev, ok := blkTab[blk]
+			if ok {
+				delete(Zinblk[zprev], blk)
+			} else {
+				zprev = ø
+			}
+
+			if zblk != ø {
+				blkTab[blk] = zblk
+				inblk, ok := Zinblk[zblk]
+				if !ok {
+					inblk = SetI64{}
+					Zinblk[zblk] = inblk
+				}
+				inblk.Add(blk)
+			}
+
+			// update δf due to change in blkTab
+			if zblk != zprev {
+				δf.Add(blk)
+			}
+		}
+
+		// update δf due to change in ZBlk data
+		for zblk := range test.δblkData {
+			for blk := range Zinblk[zblk] {
+				δf.Add(blk)
+			}
+		}
+
+		vδf = append(vδf, ΔFile{
+				Rev:    zodb.InvalidTid, // XXX will be set after treegen commit
+				Blocks: δf,
+				Size:   false/*XXX*/,
+		})
+	}
 }
 
 // XXX TestΔFtailRandom(t *testing.T) {