Issue #276 - Introduce ATL_Deprecate.h

src/plugin/ATL_Deprecate.h

+/**
+ * \file ATL_Deprecate.h Include package for all the ATL headers, with optional forwarding to detect ATL dependencies.
+ *
+ * This header is a nexus for refactoring work to remove ATL.
+ * The main purpose of this mechanism is to determine the exact scope of the refactoring effort.
+ * The lifetime of this header is during the work on #276 Stop using ATL https://issues.adblockplus.org/ticket/276
+ *
+ * This file implements namespace forwarding that allows detection of ATL symbols.
+ * This forwarding is ordinarily disabled, and always disabled in Release configuration for safety.
+ * When forwarding is disabled, it simply includes the ATL headers.
+ * With forwarding turned on, the ATL headers are included within a namespace,
+ *   then particular ATL items used are then manually reintroduced into visibility.
+ * This method requires explicitly enumerating each of the symbols needed to get the code to compile.
+ *
+ * When the ATL namespace is forwarded, the code does not link.
+ * Since forwarding the namespace is a code analysis tool, this is OK.
+ * The ATL DLL libraries expose symbols in the ATL namespace.
+ * The forwarded libraries use a different namespace.
+ * Thus the external symbols do not match, and the linker reports unresolved externals.
+ */
+
+/*
+ * NDEBUG is defined for release but not for debug, so release versions never forward.
+ * Because the plugin doesn't link correctly with forwarding turned off, forwarding is disabled by default even for debug.
+ */
+#define DISABLE_FORWARDING_FOR_DEBUG 1
+#define DISABLE_ATL_FORWARDING defined(NDEBUG) || DISABLE_FORWARDING_FOR_DEBUG
+
+#if DISABLE_ATL_FORWARDING
+
+#include <atlbase.h>
+#include <atlstr.h>
+#include <atltypes.h>
+#include <atlcom.h>
+
+#else
+
+/*
+ * ATL requires the following includes in the global namespace.
+ */
+#include <apiset.h>
+#include <apisetcconv.h>
+#include <rpc.h>
+#include <rpcndr.h>
+#include <pshpack8.h>
+#include <stddef.h>
+#include <string.h>
+#include <malloc.h>
+#include <mbstring.h>
+#include <wchar.h>
+#include <tchar.h>
+#include <stdlib.h>
+#include <comutil.h>
+#include <OaIdl.h>
+#include <ObjIdl.h>
+#include <new>
+#include <propsys.h>
+#include <ShObjIdl.h>
+#include <ShlObj.h>
+#include <Shlwapi.h>
+#include <MsHTML.h>
+#include <crtdbg.h>
+#include <ole2.h>
+#include <MsHtmHst.h>
+
+/*
+ * ATL is used as an explicit global namespace within ATL itself.
+ * These declarations forward the wrapped ATL namespace back into the global one.
+ * Fortuitously, none of the plugin code uses explicitly global ATL 
+ */
+namespace OLD_ATL {
+  namespace ATL {
+  }
+}
+namespace ATL = OLD_ATL::ATL ;
+
+namespace OLD_ATL {
+  /*
+   * We need to bring some globals back into this namespace.
+   */
+  using ::tagVARIANT ;
+  using ::IStream ;
+
+  /*
+   * The original ATL include files.
+   */
+  #include <atlbase.h>
+  #include <atlstr.h>
+  #include <atltypes.h>
+  #include <atlcom.h>
+}
+
+/*
+ * The list of symbols that appear in the code.
+ * Each needs to be explicitly incorporated back in the global namespace when forwarding is on.
+ */
+using OLD_ATL::_AtlBaseModule;
+using OLD_ATL::CAtlBaseModule;
+using OLD_ATL::CComAggObject;
+using OLD_ATL::CComAutoCriticalSection;
+using OLD_ATL::CComBSTR;
+using OLD_ATL::CComClassFactory;
+using OLD_ATL::CComCoClass;
+using OLD_ATL::CComCreator;
+using OLD_ATL::CComCreator2;
+using OLD_ATL::CComModule;
+using OLD_ATL::CComMultiThreadModel;
+using OLD_ATL::CComObject;
+using OLD_ATL::CComObjectNoLock;
+using OLD_ATL::CComObjectRootEx;
+using OLD_ATL::CComPtr;
+using OLD_ATL::CComQIPtr;
+using OLD_ATL::CComSingleThreadModel;
+using OLD_ATL::CComVariant;
+using OLD_ATL::CString;
+using OLD_ATL::CW2A;
+using OLD_ATL::IDispatchImpl;
+using OLD_ATL::IObjectWithSiteImpl;
+using OLD_ATL::OLE2T;
+
+#endif
+
+/*
+ * Deprecation pragmas use the compiler to identify refactoring targets.
+ */
+#if DISABLE_ATL_FORWARDING
+namespace ATL {
+#else 
+namespace OLD_ATL {
+#endif
+#pragma deprecated( CRect )
+#pragma deprecated( CSimpleArray )
+}
+
+/*
+ * Note:
+ *   The preprocessor symbols ATLASSERT and ATLTRACE appear in the source.
+ *   These resolve to nothing in Release configurations.
+ *   In Debug configurations, these are non-trivial.
+ *   ATLASSERT resolves to an expression with _CrtDbgReportW and _CrtDbgBreak.
+ *   ATLTRACE resolves to a ATL::CTraceFileAndLineInfo.
+ *   These will need to be replaced or removed.
+ */