Bend.FreespaceExtent.pack C# (CSharp) Method

        public byte[] pack()
        {
            byte[] data; Util.writeStruct(this, out data); return data;
        }

        // grow the top "top of heap"
        // .ROOT/FREELIST/HEAD -> "top of heap"
        private NewUnusedSegment growHeap(LayerWriteGroup tx, int length)
        {
            long new_addr;
            FreespaceExtent newblock_info;

            // make an atomic write-group to "carve off" a pending chunk
            LayerWriteGroup carveoff_wg =
                tx.mylayer.newWriteGroup(type: LayerWriteGroup.WriteGroupType.DISK_ATOMIC_NOFLUSH);

            // lock to make sure two threads don't carve off at the same time...
            lock (this) {
                // HACK: currently we just grab off the top of heap
                new_addr = next_allocation;
                next_allocation = next_allocation + (long)length;

                if (new_addr <= 0) {
                    throw new Exception("invalid address in allocateNewSegment: " + new_addr);
                }

                newblock_info = new FreespaceExtent();
                newblock_info.start_addr = new_addr;
                newblock_info.end_addr = new_addr + length;

                // add the pending chunk
                carveoff_wg.setValue(this.pendingKeyForAddr(new_addr),
                                     RecordUpdate.WithPayload(newblock_info.pack()));

                Console.WriteLine("allocateNewSegment - next address: " + new_addr);
                // add our new top of heap pointer
                {
                    RecordKey key = new RecordKey().appendParsedKey(".ROOT/FREELIST/HEAD");
                    carveoff_wg.setValue(key, RecordUpdate.WithPayload(Lsd.numberToLsd(next_allocation, 13)));
                }

                // commit the metadata tx
                carveoff_wg.finish();
            }

            return new NewUnusedSegment(store,newblock_info);
        }