[PATCH v5 0/1] MR11730: windowscodecs: Always pass a valid pcbRead pointer to IStream::Read().

[Shaun Ren (＠shaunren)]

Some non-conforming IStream implementations, including SharpDX, do not
handle a NULL pcbRead for Read() [^1]. This causes the game "Surviving
Deponia Playtest" to display a black main menu.

[^1]: https://github.com/sharpdx/SharpDX/blob/ab36f12303e24aa60fe804866617716b6ded...

--
  v5: windowscodecs: Always pass a valid pcbRead pointer to IStream::Read().
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/11730

[PATCH v5 1/1] windowscodecs: Always pass a valid pcbRead pointer to IStream::Read().

[Shaun Ren]

From: Shaun Ren <[e-mail]>

Some non-conforming IStream implementations, such as SharpDX, do not
handle a NULL pcbRead for Read(). This causes the game "Surviving
Deponia Playtest" to display a black main menu.

Fixes: 2a167eb4ea844a090ca0247cf233633f697e3a85
---
 dlls/windowscodecs/wincodecs_common.c | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/dlls/windowscodecs/wincodecs_common.c b/dlls/windowscodecs/wincodecs_common.c
index 8da1bfed20c..a60e4b70d98 100644
--- a/dlls/windowscodecs/wincodecs_common.c
+++ b/dlls/windowscodecs/wincodecs_common.c
@@ -188,7 +188,18 @@ HRESULT CDECL stream_getsize(IStream *stream, ULONGLONG *size)
 
 HRESULT CDECL stream_read(IStream *stream, void *buffer, ULONG read, ULONG *bytes_read)
 {
-    return IStream_Read(stream, buffer, read, bytes_read);
+    ULONG nread;
+    HRESULT hr;
+
+    /* Ensure that we always pass a non-NULL bytes_read pointer, as some
+     * implementations (e.g. SharpDX) can't handle it being NULL. */
+    if (!bytes_read)
+        bytes_read = &nread;
+
+    hr = IStream_Read(stream, buffer, read, bytes_read);
+    if (SUCCEEDED(hr) && *bytes_read != read)
+        return S_FALSE;
+    return hr;
 }
 
 HRESULT CDECL stream_seek(IStream *stream, LONGLONG ofs, DWORD origin, ULONGLONG *new_position)
-- 
GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/11730

[Shaun Ren (＠shaunren)]

On Mon Aug 24 18:11:19 2026 +0000, Shaun Ren wrote:
> changed this line in [version 5 of the diff](/wine/wine/-/merge_requests/11730/diffs?diff_id=292973&start_sha=e15407d44be385a43d9160699bea055c1f3b9d34#e8482f4c1783af5184283bfa69f723009098b2da_206_191)
> Changed to `S_FALSE`.

-- 
https://gitlab.winehq.org/wine/wine/-/merge_requests/11730#note_149731