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 #if defined(HAVE_DLOPEN)
  37 #   include <dlfcn.h>
  38     typedef void *wxDllType;
  39 #elif defined(HAVE_SHL_LOAD)
  40 #   include <dl.h>
  41     typedef shl_t wxDllType;
  42 #elif defined(__WINDOWS__)
  43 #   include <windows.h>         // needed to get HMODULE
  44     typedef HMODULE wxDllType;
  45 #elif defined(__OS2__)
  46 #   define INCL_DOS
  47 #   include <os2.h>
  48     typedef HMODULE wxDllType;
  49 #elif defined(__WXMAC__)
  50     typedef CFragConnectionID wxDllType;
  51 #else
  52 #   error "wxLibrary can't be compiled on this platform, sorry."
  53 #endif // OS
  54
  55 // LoadLibrary is defined in windows.h as LoadLibraryA, but wxDllLoader method
  56 // should be called LoadLibrary, not LoadLibraryA or LoadLibraryW!
  57 #if defined(__WIN32__) && defined(LoadLibrary)
  58 #   include "wx/msw/winundef.h"
  59 #endif
  60
  61 // ----------------------------------------------------------------------------
  62 // wxDllLoader
  63 // ----------------------------------------------------------------------------
  64
  65 /** wxDllLoader is a class providing an interface similar to unix's
  66     dlopen(). It is used by the wxLibrary framework and manages the
  67     actual loading of DLLs and the resolving of symbols in them.
  68     There are no instances of this class, it simply serves as a
  69     namespace for its static member functions.
  70 */
  71 class wxDllLoader
  72 {
  73 public:
  74     /** This function loads a shared library into memory, with libname
  75       being the basename of the library, without the filename
  76       extension. No initialisation of the library will be done.
  77       @param libname Name of the shared object to load.
  78       @param success Must point to a bool variable which will be set to TRUE or FALSE.
  79       @return A handle to the loaded DLL. Use success parameter to test if it is valid.
  80      */
  81     static wxDllType LoadLibrary(const wxString & libname, bool *success = NULL);
  82     /** This function unloads the shared library. */
  83     static void UnloadLibrary(wxDllType dll);
  84     /** This function returns a valid handle for the main program
  85       itself. */
  86     static wxDllType GetProgramHandle(void);
  87     /** This function resolves a symbol in a loaded DLL, such as a
  88       variable or function name.
  89       @param dllHandle Handle of the DLL, as returned by LoadDll().
  90       @param name Name of the symbol.
  91       @return A pointer to the symbol.
  92      */
  93     static void * GetSymbol(wxDllType dllHandle, const wxString &name);
  94
  95 private:
  96     /// forbid construction of objects
  97     wxDllLoader();
  98 };
  99
 100 // ----------------------------------------------------------------------------
 101 // wxLibrary
 102 // ----------------------------------------------------------------------------
 103
 104 class wxLibrary : public wxObject
 105 {
 106 public:
 107     wxHashTable classTable;
 108
 109 public:
 110     wxLibrary(wxDllType handle);
 111     ~wxLibrary();
 112
 113     // Get a symbol from the dynamic library
 114     void *GetSymbol(const wxString& symbname);
 115
 116     // Create the object whose classname is "name"
 117     wxObject *CreateObject(const wxString& name);
 118
 119 protected:
 120     void PrepareClasses(wxClassInfo *first);
 121
 122     wxDllType m_handle;
 123 };
 124
 125
 126
 127 // ----------------------------------------------------------------------------
 128 // wxLibraries
 129 // ----------------------------------------------------------------------------
 130
 131 class wxLibraries
 132 {
 133 public:
 134     wxLibraries();
 135     ~wxLibraries();
 136
 137     // caller is responsible for deleting the returned pointer if !NULL
 138     wxLibrary *LoadLibrary(const wxString& basename);
 139
 140     wxObject *CreateObject(const wxString& name);
 141
 142 protected:
 143     wxList m_loaded;
 144 };
 145
 146 // ----------------------------------------------------------------------------
 147 // Global variables
 148 // ----------------------------------------------------------------------------
 149
 150 extern wxLibraries wxTheLibraries;
 151
 152 // ----------------------------------------------------------------------------
 153 // Interesting defines
 154 // ----------------------------------------------------------------------------
 155
 156 #define WXDLL_ENTRY_FUNCTION() \
 157 extern "C" wxClassInfo *wxGetClassFirst(); \
 158 wxClassInfo *wxGetClassFirst() { \
 159   return wxClassInfo::GetFirst(); \
 160 }
 161
 162 #endif // wxUSE_DYNLIB_CLASS
 163
 164 #endif // _WX_DYNLIB_H__