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docs: csharp maker data structure 注释

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1476166492 2022-08-08 21:13:09 +08:00
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maker/csharp/IP2RegionMaker/XDB/Maker.cs
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@ -1,4 +1,55 @@
using System.Text;
// Copyright 2022 The Ip2Region Authors. All rights reserved.
// Use of this source code is governed by a Apache2.0-style
// license that can be found in the LICENSE file.
//
// @Author Alan Lee <lzh.shap@gmail.com>
// @Date 2022/8/8
// --- Ip2Region v2.0 data structure
//
// +----------------+--------------------------+---------------+--------------+
// | header space | vector speed up index | data payload | block index |
// +----------------+--------------------------+---------------+--------------+
// | 256 bytes | 512 KiB (fixed) | dynamic size | dynamic size |
// +----------------+--------------------------+---------------+--------------+
//
// 1. padding space : for header info like block index ptr, version, release date eg ... or any other temporary needs.
// -- 2bytes: version number, different version means structure update, it fixed to 2 for now
// -- 2bytes: index algorithm code.
// -- 4bytes: generate unix timestamp (version)
// -- 4bytes: index block start ptr
// -- 4bytes: index block end ptr
//
//
// 2. data block : region or whatever data info.
// 3. segment index block : binary index block.
// 4. vector index block : fixed index info for block index search speed up.
// space structure table:
// -- 0 -> | 1rt super block | 2nd super block | 3rd super block | ... | 255th super block
// -- 1 -> | 1rt super block | 2nd super block | 3rd super block | ... | 255th super block
// -- 2 -> | 1rt super block | 2nd super block | 3rd super block | ... | 255th super block
// -- ...
// -- 255 -> | 1rt super block | 2nd super block | 3rd super block | ... | 255th super block
//
//
// super block structure:
// +-----------------------+----------------------+
// | first index block ptr | last index block ptr |
// +-----------------------+----------------------+
//
// data entry structure:
// +--------------------+-----------------------+
// | 2bytes (for desc) | dynamic length |
// +--------------------+-----------------------+
// data length whatever in bytes
//
// index entry structure
// +------------+-----------+---------------+------------+
// | 4bytes | 4bytes | 2bytes | 4 bytes |
// +------------+-----------+---------------+------------+
// start ip end ip data length data ptr
using System.Text;
namespace IP2RegionMaker.XDB
{