// WriteAt write a needle by specified offset;
func (b *SuperBlock) WriteAt(offset uint32, n *needle.Needle) (err error) {
if b.LastErr != nil {
return b.LastErr
}
if _, err = b.w.WriteAt(n.Buffer(), needle.BlockOffset(offset)); err != nil {
b.LastErr = err
}
return
}
// ReadAt read a needle by specified offset, before call it, must set needle
// TotalSize.
func (b *SuperBlock) ReadAt(n *needle.Needle) (err error) {
if b.LastErr != nil {
return b.LastErr
}
if _, err = b.r.ReadAt(n.Buffer(), needle.BlockOffset(n.Offset)); err == nil {
err = n.Parse()
} else {
b.LastErr = err
}
return
}
// Write write needle to the block.
func (b *SuperBlock) Write(n *needle.Needle) (err error) {
if b.LastErr != nil {
return b.LastErr
}
if _maxOffset-n.IncrOffset < b.Offset {
err = errors.ErrSuperBlockNoSpace
return
}
if _, err = b.w.Write(n.Buffer()); err == nil {
err = b.flush(false)
} else {
b.LastErr = err
return
}
b.Offset += n.IncrOffset
b.Size += int64(n.TotalSize)
return
}