salieri: Support read-only mode if archive is already opened (#1807)

This improves shader cache resilience when people opens another program that touch the cache.zip.

Ryujinx.Graphics.Gpu/Shader/Cache/CacheCollection.cs

@@ -116,6 +116,8 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
         /// </summary>
         private ZipArchive _cacheArchive;
 
+        public bool IsReadOnly { get; }
+
         /// <summary>
         /// Immutable copy of the hash table.
         /// </summary>
@@ -167,6 +169,7 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
             _hashType = hashType;
             _version = version;
             _hashTable = new HashSet<Hash128>();
+            IsReadOnly = CacheHelper.IsArchiveReadOnly(GetArchivePath());
 
             Load();
 
@@ -230,6 +233,13 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
         /// <param name="entries">Entries to remove from the manifest</param>
         public void RemoveManifestEntriesAsync(HashSet<Hash128> entries)
         {
+            if (IsReadOnly)
+            {
+                Logger.Warning?.Print(LogClass.Gpu, "Trying to remove manifest entries on a read-only cache, ignoring.");
+
+                return;
+            }
+
             _fileWriterWorkerQueue.Add(new CacheFileOperationTask
             {
                 Type = CacheFileOperation.RemoveManifestEntries,
@@ -308,6 +318,20 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
 
             string archivePath = GetArchivePath();
 
+            if (IsReadOnly)
+            {
+                Logger.Warning?.Print(LogClass.Gpu, $"Cache collection archive in read-only, archiving task skipped.");
+
+                return;
+            }
+
+            if (CacheHelper.IsArchiveReadOnly(archivePath))
+            {
+                Logger.Warning?.Print(LogClass.Gpu, $"Cache collection archive in use, archiving task skipped.");
+
+                return;
+            }
+
             // Open the zip in read/write.
             _cacheArchive = ZipFile.Open(archivePath, ZipArchiveMode.Update);
 
@@ -446,6 +470,13 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
         /// <param name="value">The value to cache</param>
         public void AddValue(ref Hash128 keyHash, byte[] value)
         {
+            if (IsReadOnly)
+            {
+                Logger.Warning?.Print(LogClass.Gpu, "Trying to add {keyHash} on a read-only cache, ignoring.");
+
+                return;
+            }
+
             Debug.Assert(value != null);
 
             bool isAlreadyPresent;
@@ -488,6 +519,13 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
         /// <param name="value">The value to cache</param>
         public void ReplaceValue(ref Hash128 keyHash, byte[] value)
         {
+            if (IsReadOnly)
+            {
+                Logger.Warning?.Print(LogClass.Gpu, "Trying to replace {keyHash} on a read-only cache, ignoring.");
+
+                return;
+            }
+
             Debug.Assert(value != null);
 
             // Only queue file change operations

Ryujinx.Graphics.Gpu/Shader/Cache/CacheHelper.cs

@@ -496,5 +496,27 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
                 }
             }
         }
+
+        public static bool IsArchiveReadOnly(string archivePath)
+        {
+            FileInfo info = new FileInfo(archivePath);
+
+            if (!info.Exists)
+            {
+                return false;
+            }
+
+            try
+            {
+                using (FileStream stream = info.Open(FileMode.Open, FileAccess.Read, FileShare.None))
+                {
+                    return false;
+                }
+            }
+            catch (IOException)
+            {
+                return true;
+            }
+        }
     }
 }

Ryujinx.Graphics.Gpu/Shader/Cache/CacheManager.cs

@@ -1,9 +1,7 @@
 using Ryujinx.Common;
-using Ryujinx.Common.Configuration;
 using Ryujinx.Graphics.Gpu.Shader.Cache.Definition;
 using System;
 using System.Collections.Generic;
-using System.IO;
 
 namespace Ryujinx.Graphics.Gpu.Shader.Cache
 {
@@ -31,6 +29,8 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
         /// </summary>
         private const ulong GuestCacheVersion = 1759;
 
+        public bool IsReadOnly => _guestProgramCache.IsReadOnly || _hostProgramCache.IsReadOnly;
+
         /// <summary>
         /// Create a new cache manager instance
         /// </summary>

Ryujinx.Graphics.Gpu/Shader/Cache/CacheMigration.cs

@@ -146,7 +146,12 @@ namespace Ryujinx.Graphics.Gpu.Shader.Cache
             string guestBaseCacheDirectory = CacheHelper.GenerateCachePath(baseCacheDirectory, CacheGraphicsApi.Guest, "", "program");
             string hostBaseCacheDirectory = CacheHelper.GenerateCachePath(baseCacheDirectory, graphicsApi, shaderProvider, "host");
 
-            if (CacheHelper.TryReadManifestHeader(CacheHelper.GetManifestPath(guestBaseCacheDirectory), out CacheManifestHeader header))
+            string guestArchivePath = CacheHelper.GetArchivePath(guestBaseCacheDirectory);
+            string hostArchivePath = CacheHelper.GetArchivePath(hostBaseCacheDirectory);
+
+            bool isReadOnly = CacheHelper.IsArchiveReadOnly(guestArchivePath) || CacheHelper.IsArchiveReadOnly(hostArchivePath);
+
+            if (!isReadOnly && CacheHelper.TryReadManifestHeader(CacheHelper.GetManifestPath(guestBaseCacheDirectory), out CacheManifestHeader header))
             {
                 if (NeedHashRecompute(header.Version, out ulong newVersion))
                 {