64 lines
1.3 KiB
Go
64 lines
1.3 KiB
Go
package structr
|
|
|
|
import (
|
|
"sync"
|
|
"unsafe"
|
|
)
|
|
|
|
type indexed_item struct {
|
|
// linked list elem this item
|
|
// is stored in a main list.
|
|
elem list_elem
|
|
|
|
// indexed stores the indices
|
|
// this item is stored under.
|
|
indexed []*index_entry
|
|
|
|
// cached data with type.
|
|
data interface{}
|
|
}
|
|
|
|
var indexed_item_pool sync.Pool
|
|
|
|
// new_indexed_item returns a new prepared indexed_item.
|
|
func new_indexed_item() *indexed_item {
|
|
v := indexed_item_pool.Get()
|
|
if v == nil {
|
|
v = new(indexed_item)
|
|
}
|
|
item := v.(*indexed_item)
|
|
ptr := unsafe.Pointer(item)
|
|
item.elem.data = ptr
|
|
return item
|
|
}
|
|
|
|
// free_indexed_item releases the indexed_item.
|
|
func free_indexed_item(item *indexed_item) {
|
|
item.elem.data = nil
|
|
item.indexed = item.indexed[:0]
|
|
item.data = nil
|
|
indexed_item_pool.Put(item)
|
|
}
|
|
|
|
// drop_index will drop the given index entry from item's indexed.
|
|
// note this also handles freeing the index_entry memory (e.g. to pool)
|
|
func (i *indexed_item) drop_index(entry *index_entry) {
|
|
for x := 0; x < len(i.indexed); x++ {
|
|
if i.indexed[x] != entry {
|
|
// Prof. Obiwan:
|
|
// this is not the index
|
|
// we are looking for.
|
|
continue
|
|
}
|
|
|
|
// Unset tptr value to
|
|
// ensure GC can take it.
|
|
i.indexed[x] = nil
|
|
|
|
// Move all index entries down + reslice.
|
|
_ = copy(i.indexed[x:], i.indexed[x+1:])
|
|
i.indexed = i.indexed[:len(i.indexed)-1]
|
|
break
|
|
}
|
|
}
|