///////////////////////////////////////////////////////////////////////////// // Name: dynload.h // Purpose: Dynamic loading framework // Author: Ron Lee, David Falkinder, Vadim Zeitlin and a cast of 1000's // (derived in part from dynlib.cpp (c) 1998 Guilhem Lavaux) // Modified by: // Created: 03/12/01 // RCS-ID: $Id$ // Copyright: (c) 2001 Ron Lee // Licence: wxWindows license ///////////////////////////////////////////////////////////////////////////// #ifndef _WX_DYNAMICLOADER_H__ #define _WX_DYNAMICLOADER_H__ #if defined(__GNUG__) && !defined(__APPLE__) #pragma interface "dynload.h" #endif // ---------------------------------------------------------------------------- // headers // ---------------------------------------------------------------------------- #include "wx/defs.h" #if wxUSE_DYNAMIC_LOADER #include "wx/hashmap.h" #include "wx/module.h" // FIXME: can this go in private.h or something too?? #if defined(__WXPM__) || defined(__EMX__) #define INCL_DOS #include #endif #ifdef __WXMSW__ #include "wx/msw/private.h" #endif class WXDLLEXPORT wxPluginLibrary; WX_DECLARE_EXPORTED_STRING_HASH_MAP(wxPluginLibrary *, wxDLManifest); typedef wxDLManifest wxDLImports; // ---------------------------------------------------------------------------- // conditional compilation // ---------------------------------------------------------------------------- // Note: WXPM/EMX has to be tested first, since we want to use // native version, even if configure detected presence of DLOPEN. #if defined(__WXPM__) || defined(__EMX__) || defined(__WINDOWS__) typedef HMODULE wxDllType; #elif defined(HAVE_DLOPEN) #include typedef void *wxDllType; #elif defined(HAVE_SHL_LOAD) #include typedef shl_t wxDllType; #elif defined(__DARWIN__) typedef void *wxDllType; #elif defined(__WXMAC__) typedef CFragConnectionID wxDllType; #else #error "Dynamic Loading classes can't be compiled on this platform, sorry." #endif // --------------------------------------------------------------------------- // wxDynamicLibrary // --------------------------------------------------------------------------- //FIXME: This class isn't really common at all, it should be moved // into platform dependent files. // NOTE: this class is (deliberately) not virtual, do not attempt // to use it polymorphically. enum wxDLFlags { wxDL_LAZY = 0x00000001, // resolve undefined symbols at first use wxDL_NOW = 0x00000002, // resolve undefined symbols on load wxDL_GLOBAL = 0x00000004, // export extern symbols to subsequently // loaded libs. wxDL_VERBATIM = 0x00000008, // Attempt to load the supplied library // name without appending the usual dll // filename extension. wxDL_NOSHARE = 0x00000010, // load new DLL, don't reuse already loaded // FIXME: why? (VZ) #ifdef __osf__ wxDL_DEFAULT = wxDL_LAZY #else wxDL_DEFAULT = wxDL_LAZY | wxDL_GLOBAL #endif }; class WXDLLEXPORT wxDynamicLibrary { public: // return a valid handle for the main program itself or NULL if // back linking is not supported by the current platform (e.g. Win32) static wxDllType GetProgramHandle(); // return the platform standard DLL extension (with leading dot) static const wxChar *GetDllExt() { return ms_dllext; } wxDynamicLibrary() : m_handle(0) {} wxDynamicLibrary(wxString libname, int flags = wxDL_DEFAULT) : m_handle(0) { Load(libname, flags); } ~wxDynamicLibrary() { Unload(); } // return TRUE if the library was loaded successfully bool IsLoaded() const { return m_handle != 0; } // load the library with the given name // (full or not), return TRUE on success bool Load(wxString libname, int flags = wxDL_DEFAULT); // unload the library, also done automatically in dtor void Unload(); // Return the raw handle from dlopen and friends. wxDllType GetLibHandle() const { return m_handle; } // resolve a symbol in a loaded DLL, such as a variable or function // name. 'name' is the (possibly mangled) name of the symbol. // (use extern "C" to export unmangled names) // // Since it is perfectly valid for the returned symbol to actually be // NULL, that is not always indication of an error. Pass and test the // parameter 'success' for a true indication of success or failure to // load the symbol. // // Returns a pointer to the symbol on success, or NULL if an error // occurred or the symbol wasn't found. void *GetSymbol(const wxString& name, bool *success = 0) const; #if WXWIN_COMPATIBILITY_2_2 operator bool() const { return IsLoaded(); } #endif protected: // Platform specific shared lib suffix. static const wxChar *ms_dllext; // the handle to DLL or NULL wxDllType m_handle; // no copy ctor/assignment operators // or we'd try to unload the library twice DECLARE_NO_COPY_CLASS(wxDynamicLibrary) }; // --------------------------------------------------------------------------- // wxPluginLibrary // --------------------------------------------------------------------------- // NOTE: Do not attempt to use a base class pointer to this class. // wxDL is not virtual and we deliberately hide some of it's // methods here. // // Unless you know exacty why you need to, you probably shouldn't // instantiate this class directly anyway, use wxPluginManager // instead. class WXDLLEXPORT wxPluginLibrary : public wxDynamicLibrary { public: static wxDLImports* ms_classes; // Static hash of all imported classes. wxPluginLibrary( const wxString &libname, int flags = wxDL_DEFAULT ); ~wxPluginLibrary(); wxPluginLibrary *RefLib(); bool UnrefLib(); // These two are called by the PluginSentinel on (PLUGGABLE) object // creation/destruction. There is usually no reason for the user to // call them directly. We have to separate this from the link count, // since the two are not interchangeable. // FIXME: for even better debugging PluginSentinel should register // the name of the class created too, then we can state // exactly which object was not destroyed which may be // difficult to find otherwise. Also this code should // probably only be active in DEBUG mode, but let's just // get it right first. void RefObj() { ++m_objcount; } void UnrefObj() { wxASSERT_MSG( m_objcount > 0, _T("Too many objects deleted??") ); --m_objcount; } // Override/hide some base class methods bool IsLoaded() const { return m_linkcount > 0; } void Unload() { UnrefLib(); } private: wxClassInfo *m_before; // sm_first before loading this lib wxClassInfo *m_after; // ..and after. size_t m_linkcount; // Ref count of library link calls size_t m_objcount; // ..and (pluggable) object instantiations. wxModuleList m_wxmodules; // any wxModules that we initialised. void UpdateClassInfo(); // Update the wxClassInfo table void RestoreClassInfo(); // Restore the original wxClassInfo state. void RegisterModules(); // Init any wxModules in the lib. void UnregisterModules(); // Cleanup any wxModules we installed. DECLARE_NO_COPY_CLASS(wxPluginLibrary) }; class WXDLLEXPORT wxPluginManager { public: // Static accessors. static wxPluginLibrary *LoadLibrary( const wxString &libname, int flags = wxDL_DEFAULT ); static bool UnloadLibrary(const wxString &libname); // This is used by wxDllLoader. It's wrapped in the compatibility // macro because it's of arguable use outside of that. #if WXWIN_COMPATIBILITY_2_2 static wxPluginLibrary *GetObjectFromHandle(wxDllType handle); #endif // Instance methods. wxPluginManager() : m_entry(NULL) {}; wxPluginManager(const wxString &libname, int flags = wxDL_DEFAULT) { Load(libname, flags); } ~wxPluginManager() { Unload(); } bool Load(const wxString &libname, int flags = wxDL_DEFAULT); void Unload(); bool IsLoaded() const { return m_entry && m_entry->IsLoaded(); } void *GetSymbol(const wxString &symbol, bool *success = 0) { return m_entry->GetSymbol( symbol, success ); } static void CreateManifest() { ms_manifest = new wxDLManifest(wxKEY_STRING); } static void ClearManifest() { delete ms_manifest; ms_manifest = NULL; } private: // return the pointer to the entry for the library with given name in // ms_manifest or NULL if none static wxPluginLibrary *FindByName(const wxString& name) { const wxDLManifest::iterator i = ms_manifest->find(name); return i == ms_manifest->end() ? NULL : i->second; } static wxDLManifest* ms_manifest; // Static hash of loaded libs. wxPluginLibrary* m_entry; // Cache our entry in the manifest. // We could allow this class to be copied if we really // wanted to, but not without modification. DECLARE_NO_COPY_CLASS(wxPluginManager) }; // --------------------------------------------------------------------------- // wxDllLoader // --------------------------------------------------------------------------- // Cross platform wrapper for dlopen and friends. // There are no instances of this class, it simply // serves as a namespace for its static member functions. #if WXWIN_COMPATIBILITY_2_2 class WXDLLEXPORT wxDllLoader { public: static wxDllType LoadLibrary(const wxString& name, bool *success = NULL); static void UnloadLibrary(wxDllType dll); static wxDllType GetProgramHandle() { return wxDynamicLibrary::GetProgramHandle(); } static void *GetSymbol(wxDllType dllHandle, const wxString &name, bool *success = 0); static wxString GetDllExt() { return wxDynamicLibrary::GetDllExt(); } private: wxDllLoader(); // forbid construction of objects }; #endif #endif // wxUSE_DYNAMIC_LOADER #endif // _WX_DYNAMICLOADER_H__