feat: 准备增量更新包

General/DirectoryUtils.cs

@@ -0,0 +1,32 @@
+using MeloongCore.Extensions;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace MeloongCore {
+    public static class DirectoryUtils {
+
+        /// <summary>
+        /// 确保路径以 / 或 \ 结尾。
+        /// </summary>
+        public static string ToDirectoryFormat(string folder) => IsDirectoryFormat(folder) ? folder : folder + Path.DirectorySeparatorChar;
+
+        /// <summary>
+        /// 检查路径是否以 / 或 \ 结尾。
+        /// </summary>
+        public static bool IsDirectoryFormat(string path) => path.EndsWithF("/") || path.EndsWithF("\\");
+
+        /// <summary>
+        /// 创建文件夹，或文件所在的文件夹。
+        /// 支持长路径，文件夹已存在时不会抛出异常。
+        /// </summary>
+        public static void Create(string path) {
+            if (!IsDirectoryFormat(path)) path = Path.GetDirectoryName(path);
+            Directory.CreateDirectory(PathUtils.Shorten(path));
+        }
+
+    }
+}

General/MsDelta.cs

@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using System.IO;
 using System.Runtime.InteropServices;
 
 namespace MeloongCore {
@@ -12,7 +13,12 @@ namespace MeloongCore {
         /// <summary>
         /// 生成增量补丁文件：比较 <paramref name="oldFilePath"/> 和 <paramref name="newFilePath"/>，将补丁写入 <paramref name="deltaFilePath"/>。
         /// </summary>
+        /// <exception cref="FileNotFoundException" />
+        /// <exception cref="Win32Exception" />
         public static void Create(string oldFilePath, string newFilePath, string deltaFilePath) {
+            if (!File.Exists(oldFilePath)) throw new FileNotFoundException($"旧文件不存在：{oldFilePath}", oldFilePath);
+            if (!File.Exists(newFilePath)) throw new FileNotFoundException($"新文件不存在：{newFilePath}", newFilePath);
+            DirectoryUtils.Create(deltaFilePath);
             // fileTypeSet：https://learn.microsoft.com/en-us/previous-versions/bb417345(v=msdn.10)?redirectedfrom=MSDN#file-type-sets (15L: DELTA_FILE_TYPE_SET_EXECUTABLES)
             // 131072L: IgnoreFileSizeLimit, 32u: Crc32
             if (!CreateDelta(15L, 131072L, 0L, 
@@ -23,7 +29,12 @@ namespace MeloongCore {
         /// <summary>
         /// 应用增量补丁文件：将 <paramref name="deltaFilePath"/> 补丁应用到 <paramref name="oldFilePath"/>，将结果写入 <paramref name="newFilePath"/>。
         /// </summary>
+        /// <exception cref="FileNotFoundException" />
+        /// <exception cref="Win32Exception" />
         public static void Apply(string oldFilePath, string deltaFilePath, string newFilePath) {
+            if (!File.Exists(oldFilePath)) throw new FileNotFoundException($"旧文件不存在：{oldFilePath}", oldFilePath);
+            if (!File.Exists(deltaFilePath)) throw new FileNotFoundException($"补丁文件不存在：{deltaFilePath}", deltaFilePath);
+            DirectoryUtils.Create(newFilePath);
             // 1L: AllowLegacy
             if (!ApplyDelta(1L, PathUtils.Shorten(oldFilePath), PathUtils.Shorten(deltaFilePath), PathUtils.Shorten(newFilePath)))
                 throw new Win32Exception();