added fix for MSL under Win32 (by Steve Hartwell)

[wxWidgets.git] / include / wx / dynlib.h

diff --git a/include/wx/dynlib.h b/include/wx/dynlib.h
index 745cdddcd0eaeaefcb87135d4e4672ce723e91ce..32b569ccdb557d804503a09ad74bcbaea48ab692 100644 (file)
--- a/include/wx/dynlib.h
+++ b/include/wx/dynlib.h
@@ -1,60 +1,274 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// 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:      $Id$
 // Modified by:
 // Created:     20/07/98
 // RCS-ID:      $Id$

-// Copyright:   (c) Guilhem Lavaux
-// Licence:     wxWindows license
+// Copyright:   (c) 1998 Guilhem Lavaux
+// Licence:     wxWindows licence

 /////////////////////////////////////////////////////////////////////////////
 
 #ifndef _WX_DYNLIB_H__
 #define _WX_DYNLIB_H__
 
 /////////////////////////////////////////////////////////////////////////////
 
 #ifndef _WX_DYNLIB_H__
 #define _WX_DYNLIB_H__
 

-#ifdef __GNUG__
-    #pragma interface
+#if defined(__GNUG__) && !defined(NO_GCC_PRAGMA)
+#   pragma interface "dynlib.h"

 #endif
 
 #endif
 

-#include <wx/string.h>
-#include <wx/list.h>
-#include <wx/hash.h>
+#include "wx/setup.h"

 
 

-#if defined(HAVE_DLOPEN)
-    #include <dlfcn.h>
+#if wxUSE_DYNLIB_CLASS

 
 

-    typedef void *wxDllType;
-#elif defined(HAVE_SHLLOAD)
-    #include <dl.h>
+#include "wx/string.h"
+
+// FIXME: can this go in private.h or something too??
+#if defined(__WXPM__) || defined(__EMX__)
+#define INCL_DOS
+#include <os2.h>
+#endif

 
 

-    typedef void *wxDllType;
-#elif defined(__WINDOWS__)
-    #include <windows.h>
+#ifdef __WXMSW__
+#include "wx/msw/private.h"
+#endif

 
 

-    typedef HMODULE wxDllType;
+// ----------------------------------------------------------------------------
+// conditional compilation
+// ----------------------------------------------------------------------------
+
+// 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__) || defined(__WINDOWS__)
+    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(__DARWIN__)
+    typedef void               *wxDllType;

 #elif defined(__WXMAC__)
 #elif defined(__WXMAC__)

-    typedef CFragConnectionID wxDllType;
+    #include <CodeFragments.h>
+    typedef CFragConnectionID   wxDllType;

 #else
 #else

-    #error "wxLibrary can't be compiled on this platform, sorry."
-#endif // OS
+    #error "Dynamic Loading classes can't be compiled on this platform, sorry."
+#endif

 
 

-// defined in windows.h
-#ifdef LoadLibrary
-    #undef LoadLibrary
+// ----------------------------------------------------------------------------
+// constants
+// ----------------------------------------------------------------------------
+
+enum wxDLFlags
+{
+    wxDL_LAZY       = 0x00000001,   // resolve undefined symbols at first use
+    wxDL_NOW        = 0x00000002,   // resolve undefined symbols on load
+    wxDL_GLOBAL     = 0x00000004,   // export extern symbols to subsequently
+                                    // loaded libs.
+    wxDL_VERBATIM   = 0x00000008,   // Attempt to load the supplied library
+                                    // name without appending the usual dll
+                                    // filename extension.
+
+    wxDL_NOSHARE    = 0x00000010,   // load new DLL, don't reuse already loaded
+
+    // FIXME: why? (VZ)
+#ifdef __osf__
+    wxDL_DEFAULT    = wxDL_LAZY
+#else
+    wxDL_DEFAULT    = wxDL_LAZY | wxDL_GLOBAL

 #endif
 #endif

+};
+
+enum wxDynamicLibraryCategory
+{
+    wxDL_LIBRARY,       // standard library
+    wxDL_MODULE         // loadable module/plugin
+};
+
+enum wxPluginCategory
+{
+    wxDL_PLUGIN_GUI,    // plugin that uses GUI classes
+    wxDL_PLUGIN_BASE    // wxBase-only plugin
+};

 
 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------

-// wxLibrary
+// macros

 // ----------------------------------------------------------------------------
 
 // ----------------------------------------------------------------------------
 

-class wxLibrary : public wxObject
+// when loading a function from a DLL you always have to cast the returned
+// "void *" pointer to the correct type and, even more annoyingly, you have to
+// repeat this type twice if you want to declare and define a function pointer
+// all in one line
+//
+// this macro makes this slightly less painful by allowing you to specify the
+// type only once, as the first parameter, and creating a variable of this type
+// called "pfn<name>" initialized with the "name" from the "dynlib"
+#define wxDYNLIB_FUNCTION(type, name, dynlib) \
+    type pfn ## name = (type)(dynlib).GetSymbol(_T(#name))
+
+// ---------------------------------------------------------------------------
+// wxDynamicLibrary
+// ---------------------------------------------------------------------------
+
+class WXDLLIMPEXP_BASE wxDynamicLibrary

 {
 public:
 {
 public:

-    wxHashTable classTable;
+    // return 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();
+
+    // return the platform standard DLL extension (with leading dot)
+    static const wxChar *GetDllExt() { return ms_dllext; }
+
+    wxDynamicLibrary() : m_handle(0) { }
+    wxDynamicLibrary(const wxString& libname, int flags = wxDL_DEFAULT)
+        : m_handle(0)
+    {
+        Load(libname, flags);
+    }
+
+    // NOTE: this class is (deliberately) not virtual, do not attempt
+    //       to use it polymorphically.
+    ~wxDynamicLibrary() { Unload(); }
+
+    // return TRUE if the library was loaded successfully
+    bool IsLoaded() const { return m_handle != 0; }
+
+    // load the library with the given name (full or not), return true if ok
+    bool Load(wxString libname, int flags = wxDL_DEFAULT);
+
+    // detach the library object from its handle, i.e. prevent the object from
+    // unloading the library in its dtor -- the caller is now responsible for
+    // doing this
+    wxDllType Detach() { wxDllType h = m_handle; m_handle = 0; return h; }
+
+    // unload the given library handle (presumably returned by Detach() before)
+    static void Unload(wxDllType handle);
+
+    // unload the library, also done automatically in dtor
+    void Unload() { if ( IsLoaded() ) { Unload(m_handle); m_handle = 0; } }
+
+    // Return the raw handle from dlopen and friends.
+    wxDllType GetLibHandle() const { return m_handle; }
+
+    // resolve a symbol in a loaded DLL, such as a variable or function name.
+    // 'name' is the (possibly mangled) name of the symbol. (use extern "C" to
+    // export unmangled names)
+    //
+    // Since it is perfectly valid for the returned symbol to actually be NULL,
+    // that is not always indication of an error.  Pass and test the parameter
+    // 'success' for a true indication of success or failure to load the
+    // symbol.
+    //
+    // Returns a pointer to the symbol on success, or NULL if an error occurred
+    // or the symbol wasn't found.
+    void *GetSymbol(const wxString& name, bool *success = 0) const;
+
+
+    // return platform-specific name of dynamic library with proper extension
+    // and prefix (e.g. "foo.dll" on Windows or "libfoo.so" on Linux)
+    static wxString CanonicalizeName(const wxString& name,
+                                     wxDynamicLibraryCategory cat = wxDL_LIBRARY);

 
 

+    // return name of wxWindows plugin (adds compiler and version info
+    // to the filename):
+    static wxString
+    CanonicalizePluginName(const wxString& name,
+                           wxPluginCategory cat = wxDL_PLUGIN_GUI);
+
+    // return plugin directory on platforms where it makes sense and empty
+    // string on others:
+    static wxString GetPluginsDirectory();
+
+
+#if WXWIN_COMPATIBILITY_2_2
+    operator bool() const { return IsLoaded(); }
+#endif
+
+protected:
+    // platform specific shared lib suffix.
+    static const wxChar *ms_dllext;
+
+    // the handle to DLL or NULL
+    wxDllType m_handle;
+
+    // no copy ctor/assignment operators (or we'd try to unload the library
+    // twice)
+    DECLARE_NO_COPY_CLASS(wxDynamicLibrary)
+};
+
+
+// ----------------------------------------------------------------------------
+// wxDllLoader: low level DLL functions, use wxDynamicLibrary in your code
+// ----------------------------------------------------------------------------
+
+#if WXWIN_COMPATIBILITY_2_2 && wxUSE_DYNAMIC_LOADER
+
+/*
+    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 WXDLLIMPEXP_BASE wxDllLoader
+{

 public:
 public:

-    wxLibrary(void *handle);
-    ~wxLibrary();
+    /*
+      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& name, bool *success = NULL);
+    
+    /*
+      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() { return wxDynamicLibrary::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 = 0);
+
+    // return the standard DLL extension (with leading dot) for this platform
+    static wxString GetDllExt() { return wxDynamicLibrary::GetDllExt(); }
+
+private:
+
+    wxDllLoader();                    // forbid construction of objects
+};
+
+
+// ----------------------------------------------------------------------------
+// wxLibrary
+// ----------------------------------------------------------------------------
+
+#include "wx/hash.h"
+
+class WXDLLIMPEXP_BASE wxLibrary : public wxObject
+{
+public:
+    wxLibrary(wxDllType handle);
+    virtual ~wxLibrary();

 
     // Get a symbol from the dynamic library
     void *GetSymbol(const wxString& symbname);
 
     // Get a symbol from the dynamic library
     void *GetSymbol(const wxString& symbname);


@@ -66,13 +280,16 @@ protected:
     void PrepareClasses(wxClassInfo *first);
 
     wxDllType m_handle;
     void PrepareClasses(wxClassInfo *first);
 
     wxDllType m_handle;

+
+public:
+    wxHashTable classTable;

 };
 
 // ----------------------------------------------------------------------------
 // wxLibraries
 // ----------------------------------------------------------------------------
 
 };
 
 // ----------------------------------------------------------------------------
 // wxLibraries
 // ----------------------------------------------------------------------------
 

-class wxLibraries
+class WXDLLIMPEXP_BASE wxLibraries

 {
 public:
     wxLibraries();
 {
 public:
     wxLibraries();


@@ -91,16 +308,20 @@ protected:
 // Global variables
 // ----------------------------------------------------------------------------
 
 // Global variables
 // ----------------------------------------------------------------------------
 

-extern wxLibraries wxTheLibraries;
+extern WXDLLIMPEXP_DATA_BASE(wxLibraries) wxTheLibraries;
+
+#endif // WXWIN_COMPATIBILITY_2_2 && wxUSE_DYNAMIC_LOADER

 
 // ----------------------------------------------------------------------------
 // Interesting defines
 // ----------------------------------------------------------------------------
 
 #define WXDLL_ENTRY_FUNCTION() \
 
 // ----------------------------------------------------------------------------
 // Interesting defines
 // ----------------------------------------------------------------------------
 
 #define WXDLL_ENTRY_FUNCTION() \

-extern "C" wxClassInfo *wxGetClassFirst(); \
-wxClassInfo *wxGetClassFirst() { \
+extern "C" WXEXPORT const wxClassInfo *wxGetClassFirst(); \
+const wxClassInfo *wxGetClassFirst() { \

   return wxClassInfo::GetFirst(); \
 }
 
   return wxClassInfo::GetFirst(); \
 }
 

+#endif // wxUSE_DYNLIB_CLASS
+

 #endif // _WX_DYNLIB_H__
 #endif // _WX_DYNLIB_H__