From cc14fc3c894aee3dbab6dca17077c292ab072069 Mon Sep 17 00:00:00 2001
From: Davide Giacometti <25966642+davidegiacometti@users.noreply.github.com>
Date: Thu, 19 Jun 2025 03:05:44 +0200
Subject: [PATCH] [Peek] Fix ShellPreviewHandler Previewer (#40111)
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<!-- Enter a brief description/summary of your PR here. What does it
fix/what does it change/how was it tested (even manually, if necessary)?
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## Summary of the Pull Request

CsWin32 0.3.183 broke preview through preview handlers in Peek.

`Error in UpdatePreviewAsync, falling back to default previewer: Unable
to cast COM object of type 'System.__ComObject' to class type
'System.IntPtr'. Instances of types that represent COM components cannot
be cast to types that do not represent COM components; however they can
be cast to interfaces as long as the underlying COM component supports
QueryInterface calls for the IID of the interface.`

Signature of `CoGetClassObject` changed for last argument from `void*`
to `object`.

Thanks @AArnott 🙂

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## PR Checklist

- [ ] **Closes:** #xxx
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or any additional comments/features here -->
## Detailed Description of the Pull Request / Additional comments

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## Validation Steps Performed

Tested Preview of Office files in Peek.
---
 .../ShellPreviewHandlerPreviewer.cs                           | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/modules/peek/Peek.FilePreviewer/Previewers/ShellPreviewHandlerPreviewer/ShellPreviewHandlerPreviewer.cs b/src/modules/peek/Peek.FilePreviewer/Previewers/ShellPreviewHandlerPreviewer/ShellPreviewHandlerPreviewer.cs
index a6dd66c91f..608ce78f3f 100644
--- a/src/modules/peek/Peek.FilePreviewer/Previewers/ShellPreviewHandlerPreviewer/ShellPreviewHandlerPreviewer.cs
+++ b/src/modules/peek/Peek.FilePreviewer/Previewers/ShellPreviewHandlerPreviewer/ShellPreviewHandlerPreviewer.cs
@@ -93,12 +93,12 @@ namespace Peek.FilePreviewer.Previewers
                             // TODO: Figure out how to get it to run in a low integrity level
                             if (!HandlerFactories.TryGetValue(clsid, out var factory))
                             {
-                                var hr = PInvoke_FilePreviewer.CoGetClassObject(clsid, CLSCTX.CLSCTX_LOCAL_SERVER, null, typeof(IClassFactory).GUID, out var pFactory);
+                                var hr = PInvoke_FilePreviewer.CoGetClassObject(clsid, CLSCTX.CLSCTX_LOCAL_SERVER, null, typeof(IClassFactory).GUID, out object pFactory);
                                 Marshal.ThrowExceptionForHR(hr);
 
                                 // Storing the factory in memory helps makes the handlers load faster
                                 // TODO: Maybe free them after some inactivity or when Peek quits?
-                                factory = (IClassFactory)Marshal.GetObjectForIUnknown((IntPtr)pFactory);
+                                factory = (IClassFactory)pFactory;
                                 factory.LockServer(true);
                                 HandlerFactories.AddOrUpdate(clsid, factory, (_, _) => factory);
                             }