From d9b8e75fbb51f639c7634dff87d41cb84f98fe83 Mon Sep 17 00:00:00 2001
From: ALEXTANG <574809918@qq.com>
Date: Thu, 29 Sep 2022 17:14:31 +0800
Subject: [PATCH] Create BinaryExtension

Create BinaryExtension
---
 .../Runtime/Core/Utility/BinaryExtension.cs   | 190 ++++++++++++++++++
 .../Core/Utility/BinaryExtension.cs.meta      |   3 +
 2 files changed, 193 insertions(+)
 create mode 100644 Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs
 create mode 100644 Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs.meta

diff --git a/Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs b/Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs
new file mode 100644
index 00000000..f46586d9
--- /dev/null
+++ b/Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs
@@ -0,0 +1,190 @@
+using System;
+using System.IO;
+using TEngine.Runtime;
+
+/// <summary>
+/// 对 BinaryReader 和 BinaryWriter 的扩展方法。
+/// </summary>
+public static class BinaryExtension
+{
+    private static readonly byte[] s_CachedBytes = new byte[byte.MaxValue + 1];
+
+    /// <summary>
+    /// 从二进制流读取编码后的 32 位有符号整数。
+    /// </summary>
+    /// <param name="binaryReader">要读取的二进制流。</param>
+    /// <returns>读取的 32 位有符号整数。</returns>
+    public static int Read7BitEncodedInt32(this BinaryReader binaryReader)
+    {
+        int value = 0;
+        int shift = 0;
+        byte b;
+        do
+        {
+            if (shift >= 35)
+            {
+                throw new Exception("7 bit encoded int is invalid.");
+            }
+
+            b = binaryReader.ReadByte();
+            value |= (b & 0x7f) << shift;
+            shift += 7;
+        } while ((b & 0x80) != 0);
+
+        return value;
+    }
+
+    /// <summary>
+    /// 向二进制流写入编码后的 32 位有符号整数。
+    /// </summary>
+    /// <param name="binaryWriter">要写入的二进制流。</param>
+    /// <param name="value">要写入的 32 位有符号整数。</param>
+    public static void Write7BitEncodedInt32(this BinaryWriter binaryWriter, int value)
+    {
+        uint num = (uint)value;
+        while (num >= 0x80)
+        {
+            binaryWriter.Write((byte)(num | 0x80));
+            num >>= 7;
+        }
+
+        binaryWriter.Write((byte)num);
+    }
+
+    /// <summary>
+    /// 从二进制流读取编码后的 32 位无符号整数。
+    /// </summary>
+    /// <param name="binaryReader">要读取的二进制流。</param>
+    /// <returns>读取的 32 位无符号整数。</returns>
+    public static uint Read7BitEncodedUInt32(this BinaryReader binaryReader)
+    {
+        return (uint)Read7BitEncodedInt32(binaryReader);
+    }
+
+    /// <summary>
+    /// 向二进制流写入编码后的 32 位无符号整数。
+    /// </summary>
+    /// <param name="binaryWriter">要写入的二进制流。</param>
+    /// <param name="value">要写入的 32 位无符号整数。</param>
+    public static void Write7BitEncodedUInt32(this BinaryWriter binaryWriter, uint value)
+    {
+        Write7BitEncodedInt32(binaryWriter, (int)value);
+    }
+
+    /// <summary>
+    /// 从二进制流读取编码后的 64 位有符号整数。
+    /// </summary>
+    /// <param name="binaryReader">要读取的二进制流。</param>
+    /// <returns>读取的 64 位有符号整数。</returns>
+    public static long Read7BitEncodedInt64(this BinaryReader binaryReader)
+    {
+        long value = 0L;
+        int shift = 0;
+        byte b;
+        do
+        {
+            if (shift >= 70)
+            {
+                throw new Exception("7 bit encoded int is invalid.");
+            }
+
+            b = binaryReader.ReadByte();
+            value |= (b & 0x7fL) << shift;
+            shift += 7;
+        } while ((b & 0x80) != 0);
+
+        return value;
+    }
+
+    /// <summary>
+    /// 向二进制流写入编码后的 64 位有符号整数。
+    /// </summary>
+    /// <param name="binaryWriter">要写入的二进制流。</param>
+    /// <param name="value">要写入的 64 位有符号整数。</param>
+    public static void Write7BitEncodedInt64(this BinaryWriter binaryWriter, long value)
+    {
+        ulong num = (ulong)value;
+        while (num >= 0x80)
+        {
+            binaryWriter.Write((byte)(num | 0x80));
+            num >>= 7;
+        }
+
+        binaryWriter.Write((byte)num);
+    }
+
+    /// <summary>
+    /// 从二进制流读取编码后的 64 位无符号整数。
+    /// </summary>
+    /// <param name="binaryReader">要读取的二进制流。</param>
+    /// <returns>读取的 64 位无符号整数。</returns>
+    public static ulong Read7BitEncodedUInt64(this BinaryReader binaryReader)
+    {
+        return (ulong)Read7BitEncodedInt64(binaryReader);
+    }
+
+    /// <summary>
+    /// 向二进制流写入编码后的 64 位无符号整数。
+    /// </summary>
+    /// <param name="binaryWriter">要写入的二进制流。</param>
+    /// <param name="value">要写入的 64 位无符号整数。</param>
+    public static void Write7BitEncodedUInt64(this BinaryWriter binaryWriter, ulong value)
+    {
+        Write7BitEncodedInt64(binaryWriter, (long)value);
+    }
+
+    /// <summary>
+    /// 从二进制流读取加密字符串。
+    /// </summary>
+    /// <param name="binaryReader">要读取的二进制流。</param>
+    /// <param name="encryptBytes">密钥数组。</param>
+    /// <returns>读取的字符串。</returns>
+    public static string ReadEncryptedString(this BinaryReader binaryReader, byte[] encryptBytes)
+    {
+        byte length = binaryReader.ReadByte();
+        if (length <= 0)
+        {
+            return null;
+        }
+
+        if (length > byte.MaxValue)
+        {
+            throw new Exception("String is too long.");
+        }
+
+        for (byte i = 0; i < length; i++)
+        {
+            s_CachedBytes[i] = binaryReader.ReadByte();
+        }
+
+        Utility.Encryption.GetSelfXorBytes(s_CachedBytes, 0, length, encryptBytes);
+        string value = Utility.Converter.GetString(s_CachedBytes, 0, length);
+        Array.Clear(s_CachedBytes, 0, length);
+        return value;
+    }
+
+    /// <summary>
+    /// 向二进制流写入加密字符串。
+    /// </summary>
+    /// <param name="binaryWriter">要写入的二进制流。</param>
+    /// <param name="value">要写入的字符串。</param>
+    /// <param name="encryptBytes">密钥数组。</param>
+    public static void WriteEncryptedString(this BinaryWriter binaryWriter, string value, byte[] encryptBytes)
+    {
+        if (string.IsNullOrEmpty(value))
+        {
+            binaryWriter.Write((byte)0);
+            return;
+        }
+
+        int length = Utility.Converter.GetBytes(value, s_CachedBytes);
+        if (length > byte.MaxValue)
+        {
+            throw new Exception(Utility.Text.Format("String '{0}' is too long.", value));
+        }
+
+        Utility.Encryption.GetSelfXorBytes(s_CachedBytes, encryptBytes);
+        binaryWriter.Write((byte)length);
+        binaryWriter.Write(s_CachedBytes, 0, length);
+    }
+}
diff --git a/Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs.meta b/Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs.meta
new file mode 100644
index 00000000..35278364
--- /dev/null
+++ b/Assets/TEngine/Scripts/Runtime/Core/Utility/BinaryExtension.cs.meta
@@ -0,0 +1,3 @@
+fileFormatVersion: 2
+guid: 29ffc5cfe9f6445d93c94ae60e25d607
+timeCreated: 1664441351
\ No newline at end of file