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>
  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 /** wxDllLoader is a class providing an interface similar to unix's
  65     dlopen(). It is used by the wxLibrary framework and manages the
  66     actual loading of DLLs and the resolving of symbols in them.
  67     There are no instances of this class, it simply serves as a
  68     namespace for its static member functions.
  69 */
  70 class wxDllLoader
  71 {
  72  public:
  73    /** This function loads a shared library into memory, with libname
  74        being the basename of the library, without the filename
  75        extension. No initialisation of the library will be done.
  76        @param libname Name of the shared object to load.
  77        @param success Must point to a bool variable which will be set to TRUE or FALSE.
  78        @return A handle to the loaded DLL. Use success parameter to test if it is valid.
  79    */
  80    static wxDllType LoadLibrary(const wxString & libname, bool *success = NULL);
  81    /** This function unloads the shared library. */
  82    static void UnloadLibrary(wxDllType dll);
  83    /** This function returns a valid handle for the main program
  84        itself. */
  85    static wxDllType GetProgramHandle(void);
  86    /** This function resolves a symbol in a loaded DLL, such as a
  87        variable or function name.
  88        @param dllHandle Handle of the DLL, as returned by LoadDll().
  89        @param name Name of the symbol.
  90        @return A pointer to the symbol.
  91    */
  92    static void * GetSymbol(wxDllType dllHandle, const wxString &name);
  93  private:
  94    /// forbid construction of objects
  95    wxDllLoader();
  96 };
  97
  98 // ----------------------------------------------------------------------------
  99 // wxLibrary
 100 // ----------------------------------------------------------------------------
 101
 102 class wxLibrary : public wxObject
 103 {
 104 public:
 105     wxHashTable classTable;
 106
 107 public:
 108     wxLibrary(wxDllType handle);
 109     ~wxLibrary();
 110
 111     // Get a symbol from the dynamic library
 112     void *GetSymbol(const wxString& symbname);
 113
 114     // Create the object whose classname is "name"
 115     wxObject *CreateObject(const wxString& name);
 116
 117 protected:
 118     void PrepareClasses(wxClassInfo *first);
 119
 120     wxDllType m_handle;
 121 };
 122
 123
 124
 125 // ----------------------------------------------------------------------------
 126 // wxLibraries
 127 // ----------------------------------------------------------------------------
 128
 129 class wxLibraries
 130 {
 131 public:
 132     wxLibraries();
 133     ~wxLibraries();
 134
 135     // caller is responsible for deleting the returned pointer if !NULL
 136     wxLibrary *LoadLibrary(const wxString& basename);
 137
 138     wxObject *CreateObject(const wxString& name);
 139
 140 protected:
 141     wxList m_loaded;
 142 };
 143
 144 // ----------------------------------------------------------------------------
 145 // Global variables
 146 // ----------------------------------------------------------------------------
 147
 148 extern wxLibraries wxTheLibraries;
 149
 150 // ----------------------------------------------------------------------------
 151 // Interesting defines
 152 // ----------------------------------------------------------------------------
 153
 154 #define WXDLL_ENTRY_FUNCTION() \
 155 extern "C" wxClassInfo *wxGetClassFirst(); \
 156 wxClassInfo *wxGetClassFirst() { \
 157   return wxClassInfo::GetFirst(); \
 158 }
 159
 160 #endif // wxUSE_DYNLIB_CLASS
 161
 162 #endif // _WX_DYNLIB_H__