]> git.saurik.com Git - wxWidgets.git/blobdiff - include/wx/dynlib.h
a draft of wxSSBase class - it is yet unused and hopefully doesn't break anything...
[wxWidgets.git] / include / wx / dynlib.h
index 0419db3579b7d0c287a1f652b6a1a3bd5c379839..56fd795c0b659b8c67b2079d3e5e524797c1b295 100644 (file)
@@ -1,11 +1,11 @@
 /////////////////////////////////////////////////////////////////////////////
-// Name:        dynlib.cpp
-// Purpose:     Dynamic library management
-// Author:      Guilhem Lavaux
+// Name:        wx/dynlib.h
+// Purpose:     Dynamic library loading classes
+// Author:      Guilhem Lavaux, Vadim Zeitlin, Vaclav Slavik
 // Modified by:
 // Created:     20/07/98
 // RCS-ID:      $Id$
-// Copyright:   (c) Guilhem Lavaux
+// Copyright:   (c) 1998 Guilhem Lavaux
 // Licence:     wxWindows license
 /////////////////////////////////////////////////////////////////////////////
 
 #define _WX_DYNLIB_H__
 
 #ifdef __GNUG__
-    #pragma interface
+#   pragma interface
 #endif
 
-#include <wx/string.h>
-#include <wx/list.h>
-#include <wx/hash.h>
-
-// TODO should be done by configure
-#if defined(__UNIX__) && !(defined(HAVE_DLOPEN) || defined(HAVE_SHLLOAD))
-    #if defined(__LINUX__) || defined(__SOLARIS__) || defined(__SUNOS__) || defined(__FREEBSD__)
-        #define HAVE_DLOPEN
-    #elif defined(__HPUX__)
-        #define HAVE_SHLLOAD
-    #endif // Unix flavour
-#endif // !Unix or already have some HAVE_xxx defined
+#include "wx/setup.h"
 
-#if defined(HAVE_DLOPEN)
-    #include <dlfcn.h>
+#if wxUSE_DYNAMIC_LOADER
 
-    typedef void *wxDllType;
-#elif defined(HAVE_SHLLOAD)
-    #include <dl.h>
+#include "wx/dynload.h"  // Use the new (version of) wxDynamicLibrary instead
+
+#elif wxUSE_DYNLIB_CLASS
+
+#include "wx/string.h"
+#include "wx/list.h"
+#include "wx/hash.h"
 
+// this is normally done by configure, but I leave it here for now...
+#if defined(__UNIX__) && !(defined(HAVE_DLOPEN) || defined(HAVE_SHL_LOAD))
+#   if defined(__LINUX__) || defined(__SOLARIS__) || defined(__SUNOS__) || defined(__FREEBSD__)
+#      define HAVE_DLOPEN
+#   elif defined(__HPUX__)
+#      define HAVE_SHL_LOAD
+#   endif // Unix flavour
+#endif // !Unix or already have some HAVE_xxx defined
+
+// 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__)
+#   define INCL_DOS
+#   include <os2.h>
+    typedef HMODULE wxDllType;
+#elif defined(HAVE_DLOPEN)
+#   include <dlfcn.h>
     typedef void *wxDllType;
+#elif defined(HAVE_SHL_LOAD)
+#   include <dl.h>
+    typedef shl_t wxDllType;
 #elif defined(__WINDOWS__)
-    #include <windows.h>
-
+#   include <windows.h>         // needed to get HMODULE
     typedef HMODULE wxDllType;
+#elif defined(__DARWIN__)
+    typedef void *wxDllType;
 #elif defined(__WXMAC__)
     typedef CFragConnectionID wxDllType;
 #else
-    #error "wxLibrary can't be compiled on this platform, sorry."
+#   error "wxLibrary can't be compiled on this platform, sorry."
 #endif // OS
 
-// defined in windows.h
-#ifdef LoadLibrary
-    #undef LoadLibrary
+// LoadLibrary is defined in windows.h as LoadLibraryA, but wxDllLoader method
+// should be called LoadLibrary, not LoadLibraryA or LoadLibraryW!
+#if defined(__WIN32__) && defined(LoadLibrary)
+#   include "wx/msw/winundef.h"
 #endif
 
 // ----------------------------------------------------------------------------
-// wxLibrary
+// wxDllLoader: low level DLL functions, use wxDynamicLibrary in your code
 // ----------------------------------------------------------------------------
 
-class wxLibrary : public wxObject
+/*
+    wxDllLoader is a class providing an interface similar to unix's dlopen().
+    It is used by wxDynamicLibrary wxLibrary and manages the actual loading of
+    DLLs and the resolving of symbols in them. There are no instances of this
+    class, it simply serves as a namespace for its static member functions.
+*/
+class WXDLLEXPORT wxDllLoader
 {
 public:
-    wxHashTable classTable;
+    /*
+      This function loads the shared library libname into memory.
+
+      libname may be either the full path to the file or just the filename in
+      which case the library is searched for in all standard locations
+      (use GetDllExt() to construct the filename)
+
+      if success pointer is not NULL, it will be filled with TRUE if everything
+      went ok and FALSE otherwise
+     */
+    static wxDllType LoadLibrary(const wxString& libname, bool *success = 0);
+
+    /*
+      This function unloads the shared library previously loaded with
+      LoadLibrary
+     */
+    static void UnloadLibrary(wxDllType dll);
+
+    /*
+       This function returns 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();
+
+    /*
+       This function resolves a symbol in a loaded DLL, such as a
+       variable or function name.
+
+       dllHandle Handle of the DLL, as returned by LoadDll().
+       name Name of the symbol.
+
+       Returns the pointer to the symbol or NULL on error.
+     */
+    static void *GetSymbol(wxDllType dllHandle,
+                           const wxString &name,
+                           bool *success = NULL);
+
+    // return the standard DLL extension (with leading dot) for this platform
+    static const wxString &GetDllExt() { return ms_dllext; }
+
+private:
+    // forbid construction of objects
+    wxDllLoader();
+    static const wxString   ms_dllext;
+};
+
+// ----------------------------------------------------------------------------
+// wxDynamicLibrary - friendly interface to wxDllLoader
+// ----------------------------------------------------------------------------
+
+class WXDLLEXPORT wxDynamicLibrary
+{
+public:
+    // ctors
+    wxDynamicLibrary() { m_library = 0; }
+    wxDynamicLibrary(const wxString& name) { Load(name); }
+
+    // return TRUE if the library was loaded successfully
+    bool IsLoaded() const { return m_library != 0; }
+    operator bool() const { return IsLoaded(); }
+
+    // load the library with the given name (full or not), return TRUE on
+    // success
+    bool Load(const wxString& name)
+    {
+        m_library = wxDllLoader::LoadLibrary(name);
+
+        return IsLoaded();
+    }
+
+    // unload the library, also done automatically in dtor
+    void Unload()
+    {
+        if ( IsLoaded() )
+            wxDllLoader::UnloadLibrary(m_library);
+    }
+
+    // load a symbol from the library, return NULL if an error occured or
+    // symbol wasn't found
+    void *GetSymbol(const wxString& name) const
+    {
+        wxCHECK_MSG( IsLoaded(), NULL,
+                     _T("can't load symbol from unloaded library") );
+
+        return wxDllLoader::GetSymbol(m_library, name);
+    }
+
+    // unload the library
+    //
+    // NB: dtor is not virtual, don't derive from this class
+    ~wxDynamicLibrary() { Unload(); }
+
+private:
+    // the handle to DLL or NULL
+    wxDllType m_library;
+
+    // no copy ctor/assignment operators (or we'd try to unload the library
+    // twice)
+    DECLARE_NO_COPY_CLASS(wxDynamicLibrary)
+};
+
+// ----------------------------------------------------------------------------
+// wxLibrary
+// ----------------------------------------------------------------------------
 
+class WXDLLEXPORT wxLibrary : public wxObject
+{
 public:
-    wxLibrary(void *handle);
-    ~wxLibrary();
+    wxLibrary(wxDllType handle);
+    virtual ~wxLibrary();
 
     // Get a symbol from the dynamic library
     void *GetSymbol(const wxString& symbname);
@@ -75,13 +201,16 @@ protected:
     void PrepareClasses(wxClassInfo *first);
 
     wxDllType m_handle;
+
+public:
+    wxHashTable classTable;
 };
 
 // ----------------------------------------------------------------------------
 // wxLibraries
 // ----------------------------------------------------------------------------
 
-class wxLibraries
+class WXDLLEXPORT wxLibraries
 {
 public:
     wxLibraries();
@@ -100,16 +229,18 @@ protected:
 // Global variables
 // ----------------------------------------------------------------------------
 
-extern wxLibraries wxTheLibraries;
+extern WXDLLEXPORT_DATA(wxLibraries) wxTheLibraries;
 
 // ----------------------------------------------------------------------------
 // Interesting defines
 // ----------------------------------------------------------------------------
 
 #define WXDLL_ENTRY_FUNCTION() \
-extern "C" wxClassInfo *wxGetClassFirst(); \
-wxClassInfo *wxGetClassFirst() { \
+extern "C" WXEXPORT const wxClassInfo *wxGetClassFirst(); \
+const wxClassInfo *wxGetClassFirst() { \
   return wxClassInfo::GetFirst(); \
 }
 
+#endif // wxUSE_DYNLIB_CLASS
+
 #endif // _WX_DYNLIB_H__