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