[PATCH v4 0/1] MR10869: atl: Implement registering ATL window messages.

[Steven Don (＠shdon)]

The [documentation](https://source.winehq.org/WineAPI/AtlAxWinInit.html) for `AtlAxWinInit` states that it initialises ATL's control hosting code by registering window classes "_and some messages_". MSDN's documentation phrases this as "_plus a couple of custom window messages_", but Wine's implementation didn't register any custom window messages.

Logging calls to `RegisterWindowMessage` showed that Visual Studio 2005, when going into Options -\> Projects and Solutions -\> VC++ Directories, calls this function to get the message IDs for custom messages name `WM_ATLGETCONTROL` and `WM_ATLGETHOST`.

I've then registered those same messages in `AtlAxWinInit` and logged when they were called in `AtlAxWin_wndproc`. Since they were called with 0 for both `wParam` and `lParam`, the only sensible implementation would be routing the calls through `AtlAxGetControl` and `AtlAxGetHost` and returning the `IUnknown` pointer from the window procedure.

This minor change now makes the VC++ Directories control in Visual Studio 2005 work as expected (and probably other stuff too). In that, it fixes one of the problems listed on the [Visual Studio 2005 AppDb page](https://appdb.winehq.org/objectManager.php?sClass=version&iId=4494), specifically as described in the comment "Building" posted by Dave on 2021-08-01.

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  v4: atl: Implement registering ATL window messages.
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/10869

[PATCH v4 1/1] atl: Implement registering ATL window messages.

[Steven Don]

From: Steven Don <[e-mail]>

The MSDN documentation for AtlAxWinInit states that it initialises ATL's
control hosting code by registering window classes *plus a couple of custom
window messages*

Logging calls to `RegisterWindowMessage` showed that Visual Studio 2005, when
going into Options -> Projects and Solutions -> VC++ Directories, calls this
function to get the message IDs for custom messages name WM_ATLGETCONTROL and
WM_ATLGETHOST.

I've then registered those same messages in AtlAxWinInit and logged when they
were called in `AtlAxWin_wndproc`. Since they were called with 0 for both
`wParam` and `lParam`, the only sensible implementation would be routing the
calls through `AtlAxGetControl` and `AtlAxGetHost` and returning the `IUnknown`
pointer from the window procedure.

This change now makes the VC++ Directories control in Visual Studio 2005 work
as expected (and probably other stuff too).
---
 dlls/atl/atl_ax.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/dlls/atl/atl_ax.c b/dlls/atl/atl_ax.c
index 4ff0a796d3b..3bf2ce662e4 100644
--- a/dlls/atl/atl_ax.c
+++ b/dlls/atl/atl_ax.c
@@ -55,6 +55,9 @@ typedef struct IOCS {
     BOOL fActive, fInPlace, fWindowless;
 } IOCS;
 
+static UINT wmAtlGetHost = 0;
+static UINT wmAtlGetControl = 0;
+
 /**********************************************************************
  * AtlAxWin class window procedure
  */
@@ -71,6 +74,18 @@ static LRESULT CALLBACK AtlAxWin_wndproc( HWND hWnd, UINT wMsg, WPARAM wParam, L
             free( ptr );
             return 0;
     }
+    if ( wMsg == wmAtlGetControl )
+    {
+        IUnknown *control = NULL;
+        AtlAxGetControl( hWnd, &control );
+        return (LRESULT)control;
+    }
+    if ( wMsg == wmAtlGetHost )
+    {
+        IUnknown *host = NULL;
+        AtlAxGetHost( hWnd, &host );
+        return (LRESULT)host;
+    }
     return DefWindowProcW( hWnd, wMsg, wParam, lParam );
 }
 
@@ -132,6 +147,11 @@ BOOL WINAPI AtlAxWinInit(void)
             return FALSE;
     }
 
+    if (!wmAtlGetControl)
+        wmAtlGetControl = RegisterWindowMessageW( L"WM_ATLGETCONTROL" );
+    if (!wmAtlGetHost)
+        wmAtlGetHost = RegisterWindowMessageW( L"WM_ATLGETHOST" );
+
     return TRUE;
 }
 
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GitLab

https://gitlab.winehq.org/wine/wine/-/merge_requests/10869

[Alexandre Julliard (＠julliard)]

Could you please add some tests?

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https://gitlab.winehq.org/wine/wine/-/merge_requests/10869#note_142436