[PATCH] include: Define the _STGMEDIUM_UNION type for C++.

[Zebediah Figura]

On 12/18/19 1:23 PM, Jeff Smith wrote:
> On Wed, Dec 18, 2019 at 11:55 AM Zebediah Figura <z.figura12 at gmail.com> wrote:
>>
>> This fixes a regression introduced by 732f67ed38a45911d726df8da5a68710d175ba1d.
>>
>> Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=47710
>> Signed-off-by: Zebediah Figura <z.figura12 at gmail.com>
>> ---
>>   include/objidl.idl | 22 +++++++++++++++++++++-
>>   1 file changed, 21 insertions(+), 1 deletion(-)
>>
>> diff --git a/include/objidl.idl b/include/objidl.idl
>> index a0ad1f6e01..a5466c3698 100644
>> --- a/include/objidl.idl
>> +++ b/include/objidl.idl
>> @@ -1426,8 +1426,11 @@ interface IAdviseSink : IUnknown
>>       default:         wireHGLOBAL hGeneric;
>>     } GDI_OBJECT;
>>
>> +/* Defining the _STGMEDIUM_UNION type yields a violation of the C spec when
>> + * NONAMELESSUNION is not defined, so only define it for C++. */
>> +cpp_quote("#ifdef __cplusplus")
>>     typedef struct _userSTGMEDIUM {
>> -    union switch(DWORD tymed) u {
>> +    union _STGMEDIUM_UNION switch(DWORD tymed) u {
>>       case TYMED_NULL:     ;
>>       case TYMED_MFPICT:   wireHMETAFILEPICT hMetaFilePict;
>>       case TYMED_ENHMF:    wireHENHMETAFILE hHEnhMetaFile;
>> @@ -1439,6 +1442,23 @@ interface IAdviseSink : IUnknown
>>       } DUMMYUNIONNAME;
>>       IUnknown *pUnkForRelease;
>>     } userSTGMEDIUM;
>> +cpp_quote("#else")
>> +cpp_quote("typedef struct _userSTGMEDIUM {")
>> +cpp_quote("    struct {")
>> +cpp_quote("        DWORD tymed;")
>> +cpp_quote("        union {")
>> +cpp_quote("            wireHMETAFILEPICT hMetaFilePict;")
>> +cpp_quote("            wireHENHMETAFILE hHEnhMetaFile;")
>> +cpp_quote("            GDI_OBJECT *hGdiHandle;")
>> +cpp_quote("            wireHGLOBAL hGlobal;")
>> +cpp_quote("            LPOLESTR lpszFileName;")
>> +cpp_quote("            BYTE_BLOB *pstm;")
>> +cpp_quote("            BYTE_BLOB *pstg;")
>> +cpp_quote("        } u;")
>> +cpp_quote("    } DUMMYUNIONNAME;")
>> +cpp_quote("    IUnknown *pUnkForRelease;")
>> +cpp_quote("} userSTGMEDIUM;")
>> +cpp_quote("#endif")
>>
>>     typedef [unique] userSTGMEDIUM *wireSTGMEDIUM;
>>     typedef [wire_marshal(wireSTGMEDIUM)] uSTGMEDIUM STGMEDIUM;
>> --
>> 2.24.1
> 
> Hi Zebediah,
> 
> I know this is getting into a "what's the least bad way to handle a
> bad situation"...
> But I'm wondering if defining away _STGMEDIUM_UNION for C wouldn't be
> marginally better than pre-baking the code for C as you've done here.
> Something along the lines of (I'm not where I can really test this) ...
> 
> +cpp_quote("#ifndef __cplusplus")
> +cpp_quote("#define _STGMEDIUM_UNION")
> +cpp_quote("#endif")
>     typedef struct _userSTGMEDIUM {
> -    union switch(DWORD tymed) u {
> +    union _STGMEDIUM_UNION switch(DWORD tymed) u {
> ...
> +cpp_quote("#ifndef __cplusplus")
> +cpp_quote("#undef _STGMEDIUM_UNION")
> +cpp_quote("#endif")

Sure, that works too. I don't really have a preference.

> 
> -- Jeff
>