Make DoGetBestSize cache the value of GetSize() the first time it is called

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

diff --git a/include/wx/dynlib.h b/include/wx/dynlib.h
index 6e84eda08b95a6c7738cf77844cf35265d11bdf4..32b569ccdb557d804503a09ad74bcbaea48ab692 100644 (file)
--- a/include/wx/dynlib.h
+++ b/include/wx/dynlib.h
@@ -1,19 +1,19 @@
 /////////////////////////////////////////////////////////////////////////////
 /////////////////////////////////////////////////////////////////////////////

-// 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
 
 #include "wx/setup.h"
 #endif
 
 #include "wx/setup.h"


@@ -21,126 +21,240 @@
 #if wxUSE_DYNLIB_CLASS
 
 #include "wx/string.h"
 #if wxUSE_DYNLIB_CLASS
 
 #include "wx/string.h"

-#include "wx/list.h"
-#include "wx/hash.h"

 
 

-// this is normally done by configure, but I leave it here for now...
-#if defined(__UNIX__) && !(defined(HAVE_DLOPEN) || defined(HAVE_SHL_LOAD))
-#   if defined(__LINUX__) || defined(__SOLARIS__) || defined(__SUNOS__) || defined(__FREEBSD__)
-#      define HAVE_DLOPEN
-#   elif defined(__HPUX__)
-#      define HAVE_SHL_LOAD
-#   endif // Unix flavour
-#endif // !Unix or already have some HAVE_xxx defined
+// FIXME: can this go in private.h or something too??
+#if defined(__WXPM__) || defined(__EMX__)
+#define INCL_DOS
+#include <os2.h>
+#endif
+
+#ifdef __WXMSW__
+#include "wx/msw/private.h"
+#endif
+
+// ----------------------------------------------------------------------------
+// conditional compilation
+// ----------------------------------------------------------------------------

 
 // Note: WXPM/EMX has to be tested first, since we want to use
 // native version, even if configure detected presence of DLOPEN.
 
 // 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__)
-#   define INCL_DOS
-#   include <os2.h>
-    typedef HMODULE wxDllType;
+#if defined(__WXPM__) || defined(__EMX__) || defined(__WINDOWS__)
+    typedef HMODULE             wxDllType;

 #elif defined(HAVE_DLOPEN)
 #elif defined(HAVE_DLOPEN)

-#   include <dlfcn.h>
-    typedef void *wxDllType;
+    #include <dlfcn.h>
+    typedef void               *wxDllType;

 #elif defined(HAVE_SHL_LOAD)
 #elif defined(HAVE_SHL_LOAD)

-#   include <dl.h>
-    typedef shl_t wxDllType;
-#elif defined(__WINDOWS__)
-#   include <windows.h>         // needed to get HMODULE
-    typedef HMODULE wxDllType;
-#elif defined(__APPLE__) && defined(__UNIX__)
-    typedef void *wxDllType;
+    #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

 
 

-// LoadLibrary is defined in windows.h as LoadLibraryA, but wxDllLoader method
-// should be called LoadLibrary, not LoadLibraryA or LoadLibraryW!
-#if defined(__WIN32__) && defined(LoadLibrary)
-#   include "wx/msw/winundef.h"
+// ----------------------------------------------------------------------------
+// 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
+};

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

-// wxDllLoader
+// macros

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

-/** wxDllLoader is a class providing an interface similar to unix's
-    dlopen(). It is used by the wxLibrary framework 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 WXDLLEXPORT wxDllLoader
+// 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:

-    /** This function loads a shared library into memory, with libname
-      being the basename of the library, without the filename
-      extension. No initialisation of the library will be done.
-      @param libname Name of the shared object to load.
-      @param success Must point to a bool variable which will be set to TRUE or FALSE.
-      @return A handle to the loaded DLL. Use success parameter to test if it is valid.
-     */
-    static wxDllType LoadLibrary(const wxString & libname, bool *success = NULL);
-    /** This function unloads the shared library. */
-    static void UnloadLibrary(wxDllType dll);
-    /** This function returns a valid handle for the main program
-      itself. */
-    static wxDllType GetProgramHandle(void);
-    /** This function resolves a symbol in a loaded DLL, such as a
-      variable or function name.
-      @param dllHandle Handle of the DLL, as returned by LoadDll().
-      @param name Name of the symbol.
-      @return A pointer to the symbol.
-     */
-    static void * GetSymbol(wxDllType dllHandle, const wxString &name);
+    // 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 standard DLL extension (with leading dot) for this platform
-    static wxString GetDllExt();
+    // return the platform standard DLL extension (with leading dot)
+    static const wxChar *GetDllExt() { return ms_dllext; }

 
 

-private:
-    /// forbid construction of objects
-    wxDllLoader();
+    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)

 };
 
 };
 

+

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

-// wxDynamicLibrary - friendly interface to wxDllLoader
+// wxDllLoader: low level DLL functions, use wxDynamicLibrary in your code

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

-class wxDynamicLibrary
+#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:

-    wxDynamicLibrary() { m_library = 0; }
-    wxDynamicLibrary(const wxString& name) { Load(name); }
+    /*
+      This function loads the shared library libname into memory.

 
 

-    bool IsLoaded() const { return m_library != 0; }
+      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)

 
 

-    bool Load(const wxString& name)
-    {
-        m_library = wxDllLoader::LoadLibrary(name);
+      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);

 
 

-        return IsLoaded();
-    }
+    /*
+       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(); }

 
 

-    void Unload()
-    {
-        if ( IsLoaded() )
-            wxDllLoader::UnloadLibrary(m_library)
-    }
+    /*
+       This function resolves a symbol in a loaded DLL, such as a
+       variable or function name.

 
 

-    void *GetSymbol(const wxString& name) const
-    {
-        wxCHECK_MSG( IsLoaded(), NULL,
-                     _T("can't load symbol from unloaded library") );
+       dllHandle Handle of the DLL, as returned by LoadDll().
+       name Name of the symbol.

 
 

-        return wxDllLoader::GetSymbol(m_library, name);
-    }
+       Returns the pointer to the symbol or NULL on error.
+     */
+    static void *GetSymbol(wxDllType dllHandle, const wxString &name, bool *success = 0);

 
 

-    ~wxDynamicLibrary() { Unload(); }
+    // return the standard DLL extension (with leading dot) for this platform
+    static wxString GetDllExt() { return wxDynamicLibrary::GetDllExt(); }

 
 private:
 
 private:

-    wxDllType m_library;
+
+    wxDllLoader();                    // forbid construction of objects

 };
 
 
 };
 
 


@@ -148,14 +262,13 @@ private:
 // wxLibrary
 // ----------------------------------------------------------------------------
 
 // wxLibrary
 // ----------------------------------------------------------------------------
 

-class WXDLLEXPORT wxLibrary : public wxObject
-{
-public:
-    wxHashTable classTable;
+#include "wx/hash.h"

 
 

+class WXDLLIMPEXP_BASE wxLibrary : public wxObject
+{

 public:
     wxLibrary(wxDllType handle);
 public:
     wxLibrary(wxDllType handle);

-    ~wxLibrary();
+    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);


@@ -167,15 +280,16 @@ protected:
     void PrepareClasses(wxClassInfo *first);
 
     wxDllType m_handle;
     void PrepareClasses(wxClassInfo *first);
 
     wxDllType m_handle;

-};
-

 
 

+public:
+    wxHashTable classTable;
+};

 
 // ----------------------------------------------------------------------------
 // wxLibraries
 // ----------------------------------------------------------------------------
 
 
 // ----------------------------------------------------------------------------
 // wxLibraries
 // ----------------------------------------------------------------------------
 

-class WXDLLEXPORT wxLibraries
+class WXDLLIMPEXP_BASE wxLibraries

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


@@ -194,15 +308,17 @@ 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(); \
 }