Add decoder for address lookup tables

Author: rickyrombo

api/spl/address_lookup_table.go

@@ -0,0 +1,43 @@
+package spl
+
+import (
+	bin "github.com/gagliardetto/binary"
+	"github.com/gagliardetto/solana-go"
+)
+
+type AddressLookupTableMeta struct {
+	DeactivationSlot           uint64
+	LastExtendedSlot           uint64
+	LastExtendedSlotStartIndex uint8
+	Authority                  []solana.PublicKey
+}
+
+type AddressLookupTable struct {
+	State     uint32
+	Meta      AddressLookupTableMeta
+	Addresses []solana.PublicKey
+}
+
+func (inst *AddressLookupTable) UnmarshalWithDecoder(decoder *bin.Decoder) error {
+	err := decoder.Decode(&inst.State)
+	if err != nil {
+		return err
+	}
+	err = decoder.Decode(&inst.Meta)
+	if err != nil {
+		return err
+	}
+	err = decoder.SetPosition(56)
+	if err != nil {
+		return err
+	}
+	for decoder.HasRemaining() {
+		pub := &solana.PublicKey{}
+		err = decoder.Decode(pub)
+		if err != nil {
+			return err
+		}
+		inst.Addresses = append(inst.Addresses, *pub)
+	}
+	return err
+}