ArchiSteamFarm/Helpers/SerializableFile.cs

   1 // ----------------------------------------------------------------------------------------------
   2 //     _                _      _  ____   _                           _____
   3 //    / \    _ __  ___ | |__  (_)/ ___| | |_  ___   __ _  _ __ ___  |  ___|__ _  _ __  _ __ ___
   4 //   / _ \  | '__|/ __|| '_ \ | |\___ \ | __|/ _ \ / _` || '_ ` _ \ | |_  / _` || '__|| '_ ` _ \
   5 //  / ___ \ | |  | (__ | | | || | ___) || |_|  __/| (_| || | | | | ||  _|| (_| || |   | | | | | |
   6 // /_/   \_\|_|   \___||_| |_||_||____/  \__|\___| \__,_||_| |_| |_||_|   \__,_||_|   |_| |_| |_|
   7 // ----------------------------------------------------------------------------------------------
   8 // |
   9 // Copyright 2015-2024 Łukasz "JustArchi" Domeradzki
  10 // Contact: JustArchi@JustArchi.net
  11 // |
  12 // Licensed under the Apache License, Version 2.0 (the "License");
  13 // you may not use this file except in compliance with the License.
  14 // You may obtain a copy of the License at
  15 // |
  16 // http://www.apache.org/licenses/LICENSE-2.0
  17 // |
  18 // Unless required by applicable law or agreed to in writing, software
  19 // distributed under the License is distributed on an "AS IS" BASIS,
  20 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  21 // See the License for the specific language governing permissions and
  22 // limitations under the License.
  23
  24 using System;
  25 using System.IO;
  26 using System.Threading;
  27 using System.Threading.Tasks;
  28 using ArchiSteamFarm.Core;
  29 using ArchiSteamFarm.Helpers.Json;
  30 using JetBrains.Annotations;
  31
  32 namespace ArchiSteamFarm.Helpers;
  33
  34 public abstract class SerializableFile : IDisposable {
  35         private static readonly SemaphoreSlim GlobalFileSemaphore = new(1, 1);
  36
  37         private readonly SemaphoreSlim FileSemaphore = new(1, 1);
  38
  39         protected string? FilePath { get; set; }
  40
  41         private bool ReadOnly;
  42         private bool SavingScheduled;
  43
  44         public void Dispose() {
  45                 Dispose(true);
  46                 GC.SuppressFinalize(this);
  47         }
  48
  49         protected virtual void Dispose(bool disposing) {
  50                 if (disposing) {
  51                         FileSemaphore.Dispose();
  52                 }
  53         }
  54
  55         /// <summary>
  56         ///     Implementing this method in your target class is crucial for providing supported functionality.
  57         ///     In order to do so, it's enough to call static <see cref="Save" /> function from the parent class, providing <code>this</code> as input parameter.
  58         ///     Afterwards, simply call your <see cref="Save" /> function whenever you need to save changes.
  59         ///     This approach will allow JSON serializer used in the <see cref="SerializableFile" /> to properly discover all of the properties used in your class.
  60         ///     Unfortunately, due to STJ's limitations, called by some "security", it's not possible for base class to resolve your properties automatically otherwise.
  61         /// </summary>
  62         /// <example>protected override Task Save() => Save(this);</example>
  63         [UsedImplicitly]
  64         protected abstract Task Save();
  65
  66         protected static async Task Save<T>(T serializableFile) where T : SerializableFile {
  67                 ArgumentNullException.ThrowIfNull(serializableFile);
  68
  69                 if (string.IsNullOrEmpty(serializableFile.FilePath)) {
  70                         throw new InvalidOperationException(nameof(serializableFile.FilePath));
  71                 }
  72
  73                 if (serializableFile.ReadOnly) {
  74                         return;
  75                 }
  76
  77                 // ReSharper disable once SuspiciousLockOverSynchronizationPrimitive - this is not a mistake, we need extra synchronization, and we can re-use the semaphore object for that
  78                 lock (serializableFile.FileSemaphore) {
  79                         if (serializableFile.SavingScheduled) {
  80                                 return;
  81                         }
  82
  83                         serializableFile.SavingScheduled = true;
  84                 }
  85
  86                 await serializableFile.FileSemaphore.WaitAsync().ConfigureAwait(false);
  87
  88                 try {
  89                         // ReSharper disable once SuspiciousLockOverSynchronizationPrimitive - this is not a mistake, we need extra synchronization, and we can re-use the semaphore object for that
  90                         lock (serializableFile.FileSemaphore) {
  91                                 serializableFile.SavingScheduled = false;
  92                         }
  93
  94                         if (serializableFile.ReadOnly) {
  95                                 return;
  96                         }
  97
  98                         string json = serializableFile.ToJsonText(Debugging.IsUserDebugging);
  99
 100                         if (string.IsNullOrEmpty(json)) {
 101                                 throw new InvalidOperationException(nameof(json));
 102                         }
 103
 104                         // We always want to write entire content to temporary file first, in order to never load corrupted data, also when target file doesn't exist
 105                         string newFilePath = $"{serializableFile.FilePath}.new";
 106
 107                         if (File.Exists(serializableFile.FilePath)) {
 108                                 string currentJson = await File.ReadAllTextAsync(serializableFile.FilePath).ConfigureAwait(false);
 109
 110                                 if (json == currentJson) {
 111                                         return;
 112                                 }
 113
 114                                 await File.WriteAllTextAsync(newFilePath, json).ConfigureAwait(false);
 115
 116                                 File.Replace(newFilePath, serializableFile.FilePath, null);
 117                         } else {
 118                                 await File.WriteAllTextAsync(newFilePath, json).ConfigureAwait(false);
 119
 120                                 File.Move(newFilePath, serializableFile.FilePath);
 121                         }
 122                 } catch (Exception e) {
 123                         ASF.ArchiLogger.LogGenericException(e);
 124                 } finally {
 125                         serializableFile.FileSemaphore.Release();
 126                 }
 127         }
 128
 129         internal async Task MakeReadOnly() {
 130                 if (ReadOnly) {
 131                         return;
 132                 }
 133
 134                 await FileSemaphore.WaitAsync().ConfigureAwait(false);
 135
 136                 try {
 137                         if (ReadOnly) {
 138                                 return;
 139                         }
 140
 141                         ReadOnly = true;
 142                 } finally {
 143                         FileSemaphore.Release();
 144                 }
 145         }
 146
 147         internal static async Task<bool> Write(string filePath, string json) {
 148                 ArgumentException.ThrowIfNullOrEmpty(filePath);
 149                 ArgumentException.ThrowIfNullOrEmpty(json);
 150
 151                 string newFilePath = $"{filePath}.new";
 152
 153                 await GlobalFileSemaphore.WaitAsync().ConfigureAwait(false);
 154
 155                 try {
 156                         // We always want to write entire content to temporary file first, in order to never load corrupted data, also when target file doesn't exist
 157                         if (File.Exists(filePath)) {
 158                                 string currentJson = await File.ReadAllTextAsync(filePath).ConfigureAwait(false);
 159
 160                                 if (json == currentJson) {
 161                                         return true;
 162                                 }
 163
 164                                 await File.WriteAllTextAsync(newFilePath, json).ConfigureAwait(false);
 165
 166                                 File.Replace(newFilePath, filePath, null);
 167                         } else {
 168                                 await File.WriteAllTextAsync(newFilePath, json).ConfigureAwait(false);
 169
 170                                 File.Move(newFilePath, filePath);
 171                         }
 172
 173                         return true;
 174                 } catch (Exception e) {
 175                         ASF.ArchiLogger.LogGenericException(e);
 176
 177                         return false;
 178                 } finally {
 179                         GlobalFileSemaphore.Release();
 180                 }
 181         }
 182 }