func itemValWrite(coll *gkvlite.Collection, i *gkvlite.Item,
w io.WriterAt, offset int64) error {
if !strings.HasSuffix(coll.Name(), COLL_SUFFIX_CHANGES) {
_, err := w.WriteAt(i.Val, offset)
return err
}
if i.Val != nil {
_, err := w.WriteAt(i.Val, offset)
return err
}
if i.Transient == unsafe.Pointer(nil) {
panic(fmt.Sprintf("itemValWrite saw nil Transient, i: %#v", i))
}
ti := (interface{})(i.Transient)
item, ok := ti.(*item)
if !ok {
panic(fmt.Sprintf("itemValWrite invoked on non-item, i: %#v", i))
}
if item == nil {
panic(fmt.Sprintf("itemValWrite invoked on nil item, i: %#v", i))
}
vBytes := item.toValueBytes()
_, err := w.WriteAt(vBytes, offset)
return err
}
func itemValLength(coll *gkvlite.Collection, i *gkvlite.Item) int {
if !strings.HasSuffix(coll.Name(), COLL_SUFFIX_CHANGES) {
return len(i.Val)
}
if i.Val != nil {
return len(i.Val)
}
if i.Transient == unsafe.Pointer(nil) {
// TODO: The item might have nil Val when gkvlite is
// traversing with a withValue of false; so we haven't
// read/unmarshal'ed the Val/Transient yet. Impact: the byte
// aggregate math might wrong, and if we try to write with
// this 0 length, it'll be wrong; but, assuming here that the
// item.Loc() is non-empty so we'll never try to write this
// nil Val/Transient.
// panic(fmt.Sprintf("itemValLength saw nil Transient, i: %#v, coll.name: %v",
// i, coll.Name()))
return 0
}
ti := (interface{})(i.Transient)
item, ok := ti.(*item)
if !ok {
panic(fmt.Sprintf("itemValLength invoked on non-item, i: %#v", i))
}
if item == nil {
panic(fmt.Sprintf("itemValLength invoked on nil item, i: %#v", i))
}
return itemHdrLen + len(item.key) + len(item.data)
}
func itemValRead(coll *gkvlite.Collection, i *gkvlite.Item,
r io.ReaderAt, offset int64, valLength uint32) error {
if i.Val != nil {
panic(fmt.Sprintf("itemValRead saw non-nil Val, i: %#v", i))
}
i.Val = make([]byte, valLength)
_, err := r.ReadAt(i.Val, offset)
if err != nil {
return err
}
if !strings.HasSuffix(coll.Name(), COLL_SUFFIX_CHANGES) {
return nil
}
x := &item{}
if err = x.fromValueBytes(i.Val); err != nil {
return err
}
atomic.StorePointer(&i.Transient, unsafe.Pointer(x))
return nil
}