Resolve GCC's 'type-punned pointer will break strict-aliasing rules' warning by break...

[wxWidgets.git] / include / wx / dynlib.h

diff --git a/include/wx/dynlib.h b/include/wx/dynlib.h
index a6a45f74c11acfef531fd96b2fd376772c53d5af..1057f09cae3630bc784b15364430249cc5ca1ca2 100644 (file)
--- a/include/wx/dynlib.h
+++ b/include/wx/dynlib.h
@@ -73,11 +73,21 @@ enum wxDLFlags
     wxDL_VERBATIM   = 0x00000008,   // attempt to load the supplied library
                                     // name without appending the usual dll
                                     // filename extension.
+
+    // this flag is obsolete, don't use
     wxDL_NOSHARE    = 0x00000010,   // load new DLL, don't reuse already loaded
                                     // (only for wxPluginManager)
 
     wxDL_QUIET      = 0x00000020,   // don't log an error if failed to load
 
+    // this flag is dangerous, for internal use of wxMSW only, don't use at all
+    // and especially don't use directly, use wxLoadedDLL instead if you really
+    // do need it
+    wxDL_GET_LOADED = 0x00000040,   // Win32 only: return handle of already
+                                    // loaded DLL or NULL otherwise; Unload()
+                                    // should not be called so don't forget to
+                                    // Detach() if you use this function
+
     wxDL_DEFAULT    = wxDL_NOW      // default flags correspond to Win32
 };
 
@@ -106,7 +116,7 @@ enum wxPluginCategory
 // type only once, as the first parameter, and creating a variable of this type
 // called "pfn<name>" initialized with the "name" from the "dynlib"
 #define wxDYNLIB_FUNCTION(type, name, dynlib) \
-    type pfn ## name = (type)(dynlib).GetSymbol(_T(#name))
+    type pfn ## name = (type)(dynlib).GetSymbol(wxT(#name))
 
 
 // a more convenient function replacing wxDYNLIB_FUNCTION above
@@ -347,6 +357,19 @@ public:
     static wxString GetPluginsDirectory();
 
 
+#ifdef __WXMSW__
+    // return the handle (HMODULE/HINSTANCE) of the DLL with the given name
+    // and/or containing the specified address: for XP and later systems only
+    // the address is used and the name is ignored but for the previous systems
+    // only the name (which may be either a full path to the DLL or just its
+    // base name, possibly even without extension) is used
+    //
+    // the returned handle reference count is not incremented so it doesn't
+    // need to be freed using FreeLibrary() but it also means that it can
+    // become invalid if the DLL is unloaded
+    static HINSTANCE MSWGetModuleHandle(const char *name, void *addr);
+#endif // __WXMSW__
+
 protected:
     // common part of GetSymbol() and HasSymbol()
     void *DoGetSymbol(const wxString& name, bool *success = 0) const;
@@ -365,9 +388,31 @@ protected:
 
     // no copy ctor/assignment operators (or we'd try to unload the library
     // twice)
-    DECLARE_NO_COPY_CLASS(wxDynamicLibrary)
+    wxDECLARE_NO_COPY_CLASS(wxDynamicLibrary);
 };
 
+#ifdef __WXMSW__
+
+// ----------------------------------------------------------------------------
+// wxLoadedDLL is a MSW-only internal helper class allowing to dynamically bind
+// to a DLL already loaded into the project address space
+// ----------------------------------------------------------------------------
+
+class wxLoadedDLL : public wxDynamicLibrary
+{
+public:
+    wxLoadedDLL(const wxString& dllname)
+        : wxDynamicLibrary(dllname, wxDL_GET_LOADED | wxDL_VERBATIM | wxDL_QUIET)
+    {
+    }
+
+    ~wxLoadedDLL()
+    {
+        Detach();
+    }
+};
+
+#endif // __WXMSW__
 
 // ----------------------------------------------------------------------------
 // Interesting defines