.

go/neo/client/cache_test.go

@@ -29,4 +29,9 @@ func TestCache(t *testing.T) {
 	//	q<85	-> a) inside 90.serial..90  b) outside
 	//
 	// XXX cases when .serial=0 (not yet determined - 1st loadBefore is in progress)
+	// XXX for every serial check before = (s-1, s, s+1)
+
+	// merge: rce + rceNext
+	//	  rcePrev + rce
+	//	  rcePrev + (rce + rceNext)
 }

go/neo/client/list.go

+// Copyright (C) 2017  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 client
+// base for intrusive list
+
+// listHead is a list head entry for an element in an intrusive doubly-linked list.
+//
+// XXX doc how to get to container of this list head via unsafe.OffsetOf
+//
+// always call Init() to initialize a head before using it.
+type listHead struct {
+	// XXX needs to be created with .next = .prev = self
+	next, prev *listHead
+}
+
+// Init initializes a head making it point to itself via .next and .prev
+func (h *listHead) Init() {
+	h.next = h
+	h.prev = h
+}
+
+// Delete deletes h from its list
+func (h *listHead) Delete() {
+	h.next.prev = h.prev
+	h.prev.next = h.next
+	h.init()
+}
+
+// MoveBefore moves a to be before b
+// XXX ok to move if a was not previously on the list?
+func (a *listHead) MoveBefore(b *listHead) {
+	a.Delete()
+
+	a.next = b
+	b.prev = a
+	a.prev = b.prev
+	a.prev.next = a
+}