msi: Call Custom function via wrapper.

dlls/msi/custom.c

@@ -647,6 +647,28 @@ static UINT get_action_info( const GUID *guid, INT *type, MSIHANDLE *handle,
     return ERROR_SUCCESS;
 }
 
+#ifdef __i386__
+extern UINT CUSTOMPROC_wrapper( MsiCustomActionEntryPoint proc, MSIHANDLE handle );
+__ASM_GLOBAL_FUNC( CUSTOMPROC_wrapper,
+	"pushl %ebp\n\t"
+	__ASM_CFI(".cfi_adjust_cfa_offset 4\n\t")
+	__ASM_CFI(".cfi_rel_offset %ebp,0\n\t")
+	"movl %esp,%ebp\n\t"
+	__ASM_CFI(".cfi_def_cfa_register %ebp\n\t")
+	"pushl 12(%ebp)\n\t"
+	"movl 8(%ebp),%eax\n\t"
+	"call *%eax\n\t"
+	"leave\n\t"
+	__ASM_CFI(".cfi_def_cfa %esp,4\n\t")
+	__ASM_CFI(".cfi_same_value %ebp\n\t")
+	"ret" )
+#else
+static inline UINT CUSTOMPROC_wrapper( MsiCustomActionEntryPoint proc, MSIHANDLE handle )
+{
+	return proc(handle);
+}
+#endif
+
 static DWORD ACTION_CallDllFunction( const GUID *guid )
 {
     MsiCustomActionEntryPoint fn;
@@ -685,7 +707,7 @@ static DWORD ACTION_CallDllFunction( const GUID *guid )
 
             __TRY
             {
-                r = fn( hPackage );
+                r = CUSTOMPROC_wrapper( fn, hPackage );
             }
             __EXCEPT_PAGE_FAULT
             {