Revert "Refactor current GAE abstraction library to be free of the SDK*"

go/src/infra/gae/libs/wrapper/unsafe/memcache.go

+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package unsafe
+
+import (
+        "time"
+
+        "unsafe"
+
+        "appengine/memcache"
+)
+
+// Item is duplicated from appengine/memcache.
+type Item struct {
+        Key        string
+        Value      []byte
+        Object     interface{}
+        Flags      uint32
+        Expiration time.Duration
+        CasID      uint64
+}
+
+func init() {
+        // we can't actually refer to casID by name, but we can refer to everything
+        // else, and ensure that everything lines up. This should catch an api change,
+        // but wouldn't catch something like uint64 -> int64.
+        if unsafe.Sizeof(memcache.Item{}) != unsafe.Sizeof(Item{}) {
+                panic("memcache.Item and Item mismatch sizes")
+        }
+        if unsafe.Offsetof(memcache.Item{}.Key) != unsafe.Offsetof(Item{}.Key) {
+                panic("memcache.Item and Item mismatch Key")
+        }
+        if unsafe.Offsetof(memcache.Item{}.Value) != unsafe.Offsetof(Item{}.Value) {
+                panic("memcache.Item and Item mismatch Value")
+        }
+        if unsafe.Offsetof(memcache.Item{}.Object) != unsafe.Offsetof(Item{}.Object) {
+                panic("memcache.Item and Item mismatch Object")
+        }
+        if unsafe.Offsetof(memcache.Item{}.Flags) != unsafe.Offsetof(Item{}.Flags) {
+                panic("memcache.Item and Item mismatch Flags")
+        }
+        if unsafe.Offsetof(memcache.Item{}.Expiration) != unsafe.Offsetof(Item{}.Expiration) {
+                panic("memcache.Item and Item mismatch Expiration")
+        }
+}
+
+// MCSetCasID sets the private .casID field of memcache.Item.
+func MCSetCasID(i *memcache.Item, val uint64) {
+        mci := (*Item)(unsafe.Pointer(i))
+        mci.CasID = val
+}
+
+// MCGetCasID retrieves the private .casID field of memcache.Item.
+func MCGetCasID(i *memcache.Item) uint64 {
+        return (*Item)(unsafe.Pointer(i)).CasID
+}