include/wx/dynlib.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        dynlib.cpp
   3 // Purpose:     Dynamic library management
   4 // Author:      Guilhem Lavaux
   5 // Modified by:
   6 // Created:     20/07/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Guilhem Lavaux
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef _WX_DYNLIB_H__
  13 #define _WX_DYNLIB_H__
  14
  15 #ifdef __GNUG__
  16 #   pragma interface
  17 #endif
  18
  19 #include "wx/setup.h"
  20
  21 #if wxUSE_DYNLIB_CLASS
  22
  23 #include "wx/string.h"
  24 #include "wx/list.h"
  25 #include "wx/hash.h"
  26
  27 // this is normally done by configure, but I leave it here for now...
  28 #if defined(__UNIX__) && !(defined(HAVE_DLOPEN) || defined(HAVE_SHL_LOAD))
  29 #   if defined(__LINUX__) || defined(__SOLARIS__) || defined(__SUNOS__) || defined(__FREEBSD__)
  30 #      define HAVE_DLOPEN
  31 #   elif defined(__HPUX__)
  32 #      define HAVE_SHL_LOAD
  33 #   endif // Unix flavour
  34 #endif // !Unix or already have some HAVE_xxx defined
  35
  36 // Note: WXPM/EMX has to be tested first, since we want to use
  37 // native version, even if configure detected presence of DLOPEN.
  38 #if defined(__WXPM__) || defined(__EMX__)
  39 #   define INCL_DOS
  40 #   include <os2.h>
  41     typedef HMODULE wxDllType;
  42 #elif defined(HAVE_DLOPEN)
  43 #   include <dlfcn.h>
  44     typedef void *wxDllType;
  45 #elif defined(HAVE_SHL_LOAD)
  46 #   include <dl.h>
  47     typedef shl_t wxDllType;
  48 #elif defined(__WINDOWS__)
  49 #   include <windows.h>         // needed to get HMODULE
  50     typedef HMODULE wxDllType;
  51 #elif defined(__WXMAC__)
  52     typedef CFragConnectionID wxDllType;
  53 #else
  54 #   error "wxLibrary can't be compiled on this platform, sorry."
  55 #endif // OS
  56
  57 // LoadLibrary is defined in windows.h as LoadLibraryA, but wxDllLoader method
  58 // should be called LoadLibrary, not LoadLibraryA or LoadLibraryW!
  59 #if defined(__WIN32__) && defined(LoadLibrary)
  60 #   include "wx/msw/winundef.h"
  61 #endif
  62
  63 // ----------------------------------------------------------------------------
  64 // wxDllLoader
  65 // ----------------------------------------------------------------------------
  66
  67 /** wxDllLoader is a class providing an interface similar to unix's
  68     dlopen(). It is used by the wxLibrary framework and manages the
  69     actual loading of DLLs and the resolving of symbols in them.
  70     There are no instances of this class, it simply serves as a
  71     namespace for its static member functions.
  72 */
  73 class wxDllLoader
  74 {
  75 public:
  76     /** This function loads a shared library into memory, with libname
  77       being the basename of the library, without the filename
  78       extension. No initialisation of the library will be done.
  79       @param libname Name of the shared object to load.
  80       @param success Must point to a bool variable which will be set to TRUE or FALSE.
  81       @return A handle to the loaded DLL. Use success parameter to test if it is valid.
  82      */
  83     static wxDllType LoadLibrary(const wxString & libname, bool *success = NULL);
  84     /** This function unloads the shared library. */
  85     static void UnloadLibrary(wxDllType dll);
  86     /** This function returns a valid handle for the main program
  87       itself. */
  88     static wxDllType GetProgramHandle(void);
  89     /** This function resolves a symbol in a loaded DLL, such as a
  90       variable or function name.
  91       @param dllHandle Handle of the DLL, as returned by LoadDll().
  92       @param name Name of the symbol.
  93       @return A pointer to the symbol.
  94      */
  95     static void * GetSymbol(wxDllType dllHandle, const wxString &name);
  96
  97 private:
  98     /// forbid construction of objects
  99     wxDllLoader();
 100 };
 101
 102 // ----------------------------------------------------------------------------
 103 // wxLibrary
 104 // ----------------------------------------------------------------------------
 105
 106 class wxLibrary : public wxObject
 107 {
 108 public:
 109     wxHashTable classTable;
 110
 111 public:
 112     wxLibrary(wxDllType handle);
 113     ~wxLibrary();
 114
 115     // Get a symbol from the dynamic library
 116     void *GetSymbol(const wxString& symbname);
 117
 118     // Create the object whose classname is "name"
 119     wxObject *CreateObject(const wxString& name);
 120
 121 protected:
 122     void PrepareClasses(wxClassInfo *first);
 123
 124     wxDllType m_handle;
 125 };
 126
 127
 128
 129 // ----------------------------------------------------------------------------
 130 // wxLibraries
 131 // ----------------------------------------------------------------------------
 132
 133 class wxLibraries
 134 {
 135 public:
 136     wxLibraries();
 137     ~wxLibraries();
 138
 139     // caller is responsible for deleting the returned pointer if !NULL
 140     wxLibrary *LoadLibrary(const wxString& basename);
 141
 142     wxObject *CreateObject(const wxString& name);
 143
 144 protected:
 145     wxList m_loaded;
 146 };
 147
 148 // ----------------------------------------------------------------------------
 149 // Global variables
 150 // ----------------------------------------------------------------------------
 151
 152 extern wxLibraries wxTheLibraries;
 153
 154 // ----------------------------------------------------------------------------
 155 // Interesting defines
 156 // ----------------------------------------------------------------------------
 157
 158 #define WXDLL_ENTRY_FUNCTION() \
 159 extern "C" wxClassInfo *wxGetClassFirst(); \
 160 wxClassInfo *wxGetClassFirst() { \
 161   return wxClassInfo::GetFirst(); \
 162 }
 163
 164 #endif // wxUSE_DYNLIB_CLASS
 165
 166 #endif // _WX_DYNLIB_H__