Fix Possible OperationCancelException for WaitAsync Operations

Plugins/Flow.Launcher.Plugin.Explorer/Search/Everything/EverythingAPI.cs

@@ -48,11 +48,14 @@
 
         public static async ValueTask<bool> IsEverythingRunningAsync(CancellationToken token = default)
         {
-            await _semaphore.WaitAsync(token);
+            // We do not directly pass token here, but we check IsCancellationRequested inside the lock
+            // So that it will not raise OperationCanceledException, which is not expected by the caller.
+            await _semaphore.WaitAsync();
 
             try
             {
-                EverythingApiDllImport.Everything_GetMajorVersion();
+                if (token.IsCancellationRequested) return false;
+                _ = EverythingApiDllImport.Everything_GetMajorVersion();
                 var result = EverythingApiDllImport.Everything_GetLastError() != StateCode.IPCError;
                 return result;
             }
@@ -77,8 +80,7 @@
             if (option.MaxCount < 0)
                 throw new ArgumentOutOfRangeException(nameof(option.MaxCount), option.MaxCount, "MaxCount must be greater than or equal to 0");
 
-            await _semaphore.WaitAsync(token);
-
+            await _semaphore.WaitAsync();
 
             try
             {
@@ -130,20 +132,20 @@
                     yield break;
                 }
 
                 for (var idx = 0; idx < EverythingApiDllImport.Everything_GetNumResults(); ++idx)
                 {
                     if (token.IsCancellationRequested)
                     {
                         yield break;
                     }
 
                     EverythingApiDllImport.Everything_GetResultFullPathNameW(idx, buffer, BufferSize);
 
                     var result = new SearchResult
                     {
                         // todo the types are wrong. Everything expects uint everywhere, but we send int just above/below. how to fix? Is EverythingApiDllImport autogenerated or handmade?
                         FullPath = buffer.ToString(),
                         Type = EverythingApiDllImport.Everything_IsFolderResult(idx) ? ResultType.Folder :
                             EverythingApiDllImport.Everything_IsFileResult(idx) ? ResultType.File :
                             ResultType.Volume,
                         Score = (int)EverythingApiDllImport.Everything_GetResultRunCount( (uint)idx) 

Plugins/Flow.Launcher.Plugin.Program/Main.cs

@@ -31,19 +31,21 @@
 
         internal static PluginInitContext Context { get; private set; }
 
+        private static readonly Lock _lastIndexTimeLock = new();
+
         private static readonly List<Result> emptyResults = [];
 
         private static readonly MemoryCacheOptions cacheOptions = new() { SizeLimit = 1560 };
         private static MemoryCache cache = new(cacheOptions);
 
         private static readonly string[] commonUninstallerNames =
         {
             "uninst.exe",
             "unins000.exe",
             "uninst000.exe",
             "uninstall.exe"
         };
         private static readonly string[] commonUninstallerPrefixs =
         {
             "uninstall",//en
             "卸载",//zh-cn
@@ -59,9 +61,9 @@
             "삭제",//ko
             "деинсталирај",//sr
             "desinstalar",//pt-pt
             "desinstalar",//pt-br
             "desinstalar",//es
             "desinstalar",//es-419
             "disinstallare",//it
             "avinstallere",//nb-NO
             "odinštalovať",//sk
@@ -82,8 +84,37 @@
             {
                 var resultList = await Task.Run(async () =>
                 {
-                    await _win32sLock.WaitAsync(token);
-                    await _uwpsLock.WaitAsync(token);
+                    // We do not directly pass token here, but we check IsCancellationRequested inside the lock
+                    // So that it will not raise OperationCanceledException, which is not expected by the caller.
+                    Context.API.LogDebug(ClassName, "Preparing win32 programs");
+                    List<Win32> win32s;
+                    await _win32sLock.WaitAsync();
+                    try
+                    {
+                        win32s = [.. _win32s];
+                        if (token.IsCancellationRequested) return emptyResults;
+                    }
+                    finally
+                    {
+                        _win32sLock.Release();
+                    }
+
+                    // We do not directly pass token here, but we check IsCancellationRequested inside the lock
+                    // So that it will not raise OperationCanceledException, which is not expected by the caller.
+                    Context.API.LogDebug(ClassName, "Preparing UWP programs");
+                    List<UWPApp> uwps;
+                    await _uwpsLock.WaitAsync();
+                    try
+                    {
+                        uwps = [.. _uwps];
+                        if (token.IsCancellationRequested) return emptyResults;
+                    }
+                    finally
+                    {
+                        _uwpsLock.Release();
+                    }
+
+                    Context.API.LogDebug(ClassName, "Start querying programs");
                     try
                     {
                         // Collect all UWP Windows app directories
@@ -94,8 +125,8 @@
                             .Distinct(StringComparer.OrdinalIgnoreCase)
                             .ToArray() : null;
 
-                        return _win32s.Cast<IProgram>()
-                            .Concat(_uwps)
+                        return win32s.Cast<IProgram>()
+                            .Concat(uwps)
                             .AsParallel()
                             .WithCancellation(token)
                             .Where(HideUninstallersFilter)
@@ -109,11 +140,6 @@
                     {
                         return emptyResults;
                     }
-                    finally
-                    {
-                        _uwpsLock.Release();
-                        _win32sLock.Release();
-                    }
                 }, token);
 
                 resultList = resultList.Count != 0 ? resultList : emptyResults;
@@ -275,7 +301,12 @@
 
             var cacheEmpty = _win32sCount == 0 || _uwpsCount == 0;
 
-            if (cacheEmpty || _settings.LastIndexTime.AddHours(30) < DateTime.Now)
+            bool needReindex;
+            lock (_lastIndexTimeLock)
+            {
+                needReindex = _settings.LastIndexTime.AddHours(30) < DateTime.Now;
+            }
+            if (cacheEmpty || needReindex)
             {
                 _ = Task.Run(async () =>
                 {
@@ -298,6 +329,7 @@
         public static async Task IndexWin32ProgramsAsync()
         {
             await _win32sLock.WaitAsync();
+            Context.API.LogDebug(ClassName, "Start indexing Win32 programs");
             try
             {
                 var win32S = Win32.All(_settings);
@@ -308,7 +340,10 @@
                 }
                 ResetCache();
                 await Context.API.SaveCacheBinaryStorageAsync<List<Win32>>(Win32CacheName, Context.CurrentPluginMetadata.PluginCacheDirectoryPath);
-                _settings.LastIndexTime = DateTime.Now;
+                lock (_lastIndexTimeLock)
+                {
+                    _settings.LastIndexTime = DateTime.Now;
+                }
             }
             catch (Exception e)
             {
@@ -323,6 +358,7 @@
         public static async Task IndexUwpProgramsAsync()
         {
             await _uwpsLock.WaitAsync();
+            Context.API.LogDebug(ClassName, "Start indexing Uwp programs");
             try
             {
                 var uwps = UWPPackage.All(_settings);
@@ -333,7 +369,10 @@
                 }
                 ResetCache();
                 await Context.API.SaveCacheBinaryStorageAsync<List<UWPApp>>(UwpCacheName, Context.CurrentPluginMetadata.PluginCacheDirectoryPath);
-                _settings.LastIndexTime = DateTime.Now;
+                lock (_lastIndexTimeLock)
+                {
+                    _settings.LastIndexTime = DateTime.Now;
+                }
             }
             catch (Exception e)
             {
@@ -357,6 +396,7 @@
                 await Context.API.StopwatchLogInfoAsync(ClassName, "UWPProgram index cost", IndexUwpProgramsAsync);
             });
 
+            Context.API.LogDebug(ClassName, "Start indexing");
             await Task.WhenAll(win32Task, uwpTask).ConfigureAwait(false);
         }