gotosocial/vendor/codeberg.org/gruf/go-structr/result.go

79 lines
1.5 KiB
Go

package structr
import (
"sync"
"unsafe"
)
var result_pool sync.Pool
type result struct {
// linked list elem this result is
// stored under in Cache.lruList.
elem list_elem
// indexed stores the indices
// this result is stored under.
indexed []*index_entry
// cached data (we maintain
// the type data here using
// an interface as any one
// instance can be T / error).
data interface{}
}
func result_acquire[T any](c *Cache[T]) *result {
// Acquire from pool.
v := result_pool.Get()
if v == nil {
v = new(result)
}
// Cast result value.
res := v.(*result)
// Push result elem to front of LRU list.
list_push_front(&c.lruList, &res.elem)
res.elem.data = unsafe.Pointer(res)
return res
}
func result_release[T any](c *Cache[T], res *result) {
// Remove result elem from LRU list.
list_remove(&c.lruList, &res.elem)
res.elem.data = nil
// Reset all result fields.
res.indexed = res.indexed[:0]
res.data = nil
// Release to pool.
result_pool.Put(res)
}
func result_drop_index[T any](res *result, index *Index[T]) {
for i := 0; i < len(res.indexed); i++ {
if res.indexed[i].index != unsafe.Pointer(index) {
// Prof. Obiwan:
// this is not the index
// we are looking for.
continue
}
// Get index entry ptr.
entry := res.indexed[i]
// Move all index entries down + reslice.
copy(res.indexed[i:], res.indexed[i+1:])
res.indexed = res.indexed[:len(res.indexed)-1]
// Release to memory pool.
index_entry_release(entry)
return
}
}