fix unused parameter warning in wxSetEnv() in release build

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

diff --git a/include/wx/dynlib.h b/include/wx/dynlib.h
index 8b3aacdfa26d6a742e9337996ca97668b4ec018f..a4916b3706ccd88578966caa2efbd6ae217da302 100644 (file)
--- a/include/wx/dynlib.h
+++ b/include/wx/dynlib.h
@@ -6,231 +6,337 @@
 // Created:     20/07/98
 // RCS-ID:      $Id$
 // Copyright:   (c) 1998 Guilhem Lavaux
 // Created:     20/07/98
 // RCS-ID:      $Id$
 // Copyright:   (c) 1998 Guilhem Lavaux

-// Licence:     wxWindows license
+// Licence:     wxWindows licence

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

-#ifdef __GNUG__
-#   pragma interface
-#endif
-
-#include "wx/setup.h"
+#include "wx/defs.h"

 
 #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
-
-// Note: WXPM/EMX has to be tested first, since we want to use
+#include "wx/dynarray.h"
+
+#if defined(__OS2__) || defined(__EMX__)
+#include "wx/os2/private.h"
+#endif
+
+#ifdef __WXMSW__
+#include "wx/msw/private.h"
+#endif
+
+// note that we have our own dlerror() implementation under Darwin
+#if (defined(HAVE_DLERROR) && !defined(__EMX__)) || defined(__DARWIN__)
+    #define wxHAVE_DYNLIB_ERROR
+#endif
+
+class WXDLLIMPEXP_FWD_BASE wxDynamicLibraryDetailsCreator;
+
+// ----------------------------------------------------------------------------
+// conditional compilation
+// ----------------------------------------------------------------------------
+
+// Note: __OS2__/EMX has to be tested first, since we want to use

 // native version, even if configure detected presence of DLOPEN.
 // 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(__OS2__) || 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
-
-// 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"
+    #error "Dynamic Loading classes can't be compiled on this platform, sorry."

 #endif
 
 // ----------------------------------------------------------------------------
 #endif
 
 // ----------------------------------------------------------------------------

-// wxDllLoader: low level DLL functions, use wxDynamicLibrary in your code
+// constants

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

-/*
-    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 WXDLLEXPORT wxDllLoader
+enum wxDLFlags

 {
 {

-public:
-    /*
-      This function loads the shared library libname into memory.
+    wxDL_LAZY       = 0x00000001,   // resolve undefined symbols at first use
+                                    // (only works on some Unix versions)
+    wxDL_NOW        = 0x00000002,   // resolve undefined symbols on load
+                                    // (default, always the case under Win32)
+    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
+                                    // (only for wxPluginManager)
+
+    wxDL_DEFAULT    = wxDL_NOW      // default flags correspond to Win32
+};
+
+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
+};

 
 

-      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)
+// ----------------------------------------------------------------------------
+// macros
+// ----------------------------------------------------------------------------

 
 

-      if success pointer is not NULL, it will be filled with TRUE if everything
-      went ok and FALSE otherwise
-     */
-    static wxDllType LoadLibrary(const wxString& libname, bool *success = NULL);
+// 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))
+
+
+// the following macros can be used to redirect a whole
+// library to a class and check at run-time if the the
+// library is present and contains all required methods.
+
+#define wxDL_METHOD_DEFINE( rettype, name, args, shortargs, defret ) \
+    typedef rettype (* name ## Type) args ; \
+    name ## Type pfn_ ## name; \
+    rettype name args \
+    { if (m_ok) return pfn_ ## name shortargs ; return defret; }
+
+#define wxDL_VOIDMETHOD_DEFINE( name, args, shortargs ) \
+    typedef void (* name ## Type) args ; \
+    name ## Type pfn_ ## name; \
+    void name args \
+    { if (m_ok) pfn_ ## name shortargs ; }
+    
+#define wxDL_METHOD_LOAD( lib, name, success ) \
+    pfn_ ## name = (name ## Type) lib->GetSymbol( wxT(#name), &success ); \
+    if (!success) return;

 
 

-    /*
-      This function unloads the shared library previously loaded with
-      LoadLibrary
-     */
-    static void UnloadLibrary(wxDllType dll);
+// ----------------------------------------------------------------------------
+// wxDynamicLibraryDetails: contains details about a loaded wxDynamicLibrary
+// ----------------------------------------------------------------------------

 
 

-    /*
-       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();
+class WXDLLIMPEXP_BASE wxDynamicLibraryDetails
+{
+public:
+    // ctor, normally never used as these objects are only created by
+    // wxDynamicLibrary::ListLoaded()
+    wxDynamicLibraryDetails() { m_address = NULL; m_length = 0; }

 
 

-    /*
-       This function resolves a symbol in a loaded DLL, such as a
-       variable or function name.
+    // get the (base) name
+    wxString GetName() const { return m_name; }

 
 

-       dllHandle Handle of the DLL, as returned by LoadDll().
-       name Name of the symbol.
+    // get the full path of this object
+    wxString GetPath() const { return m_path; }

 
 

-       Returns the pointer to the symbol or NULL on error.
-     */
-    static void * GetSymbol(wxDllType dllHandle, const wxString &name);
+    // get the load address and the extent, return true if this information is
+    // available
+    bool GetAddress(void **addr, size_t *len) const
+    {
+        if ( !m_address )
+            return false;
+
+        if ( addr )
+            *addr = m_address;
+        if ( len )
+            *len = m_length;

 
 

-    // return the standard DLL extension (with leading dot) for this platform
-    static wxString GetDllExt();
+        return true;
+    }
+
+    // return the version of the DLL (may be empty if no version info)
+    wxString GetVersion() const
+    {
+        return m_version;
+    }

 
 private:
 
 private:

-    // forbid construction of objects
-    wxDllLoader();
+    wxString m_name,
+             m_path,
+             m_version;
+
+    void *m_address;
+    size_t m_length;
+
+    friend class wxDynamicLibraryDetailsCreator;

 };
 
 };
 

+WX_DECLARE_USER_EXPORTED_OBJARRAY(wxDynamicLibraryDetails,
+                                  wxDynamicLibraryDetailsArray,
+                                  WXDLLIMPEXP_BASE);
+

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

-// wxDynamicLibrary - friendly interface to wxDllLoader
+// wxDynamicLibrary: represents a handle to a DLL/shared object

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

-class WXDLLEXPORT wxDynamicLibrary
+class WXDLLIMPEXP_BASE wxDynamicLibrary

 {
 public:
 {
 public:

-    // ctors
-    wxDynamicLibrary() { m_library = 0; }
-    wxDynamicLibrary(const wxString& name) { Load(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 TRUE if the library was loaded successfully
-    bool IsLoaded() const { return m_library != 0; }
-    operator bool() const { return IsLoaded(); }
+    // return the platform standard DLL extension (with leading dot)
+    static const wxString& GetDllExt() { return ms_dllext; }

 
 

-    // load the library with the given name (full or not), return TRUE on
-    // success
-    bool Load(const wxString& name)
+    wxDynamicLibrary() : m_handle(0) { }
+    wxDynamicLibrary(const wxString& libname, int flags = wxDL_DEFAULT)
+        : m_handle(0)

     {
     {

-        m_library = wxDllLoader::LoadLibrary(name);
-
-        return IsLoaded();
+        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(const wxString& libname, int flags = wxDL_DEFAULT);
+
+    // raw function for loading dynamic libs: always behaves as if
+    // wxDL_VERBATIM were specified and doesn't log error message if the
+    // library couldn't be loaded but simply returns NULL
+    static wxDllType RawLoad(const 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
     // unload the library, also done automatically in dtor

-    void Unload()
-    {
-        if ( IsLoaded() )
-            wxDllLoader::UnloadLibrary(m_library);
-    }
+    void Unload() { if ( IsLoaded() ) { Unload(m_handle); m_handle = 0; } }

 
 

-    // load a symbol from the library, return NULL if an error occured or
-    // symbol wasn't found
-    void *GetSymbol(const wxString& name) const
-    {
-        wxCHECK_MSG( IsLoaded(), NULL,
-                     _T("can't load symbol from unloaded library") );
+    // Return the raw handle from dlopen and friends.
+    wxDllType GetLibHandle() const { return m_handle; }

 
 

-        return wxDllLoader::GetSymbol(m_library, name);
+    // check if the given symbol is present in the library, useful to verify if
+    // a loadable module is our plugin, for example, without provoking error
+    // messages from GetSymbol()
+    bool HasSymbol(const wxString& name) const
+    {
+        bool ok;
+        DoGetSymbol(name, &ok);
+        return ok;

     }
 
     }
 

-    // unload the library
+    // 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)

     //
     //

-    // NB: dtor is not virtual, don't derive from this class
-    ~wxDynamicLibrary() { Unload(); }
+    // 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 = NULL) const;

 
 

-private:
-    // the handle to DLL or NULL
-    wxDllType m_library;
+    // low-level version of GetSymbol()
+    static void *RawGetSymbol(wxDllType handle, const wxString& name);
+    void *RawGetSymbol(const wxString& name) const
+    {
+#if defined (__WXPM__) || defined(__EMX__)
+        return GetSymbol(name);
+#else
+        return RawGetSymbol(m_handle, name);
+#endif
+    }

 
 

-    // no copy ctor/assignment operators (or we'd try to unload the library
-    // twice)
-    DECLARE_NO_COPY_CLASS(wxDynamicLibrary);
-};
+#ifdef __WXMSW__
+    // this function is useful for loading functions from the standard Windows
+    // DLLs: such functions have an 'A' (in ANSI build) or 'W' (in Unicode, or
+    // wide character build) suffix if they take string parameters
+    static void *RawGetSymbolAorW(wxDllType handle, const wxString& name)
+    {
+        return RawGetSymbol
+               (
+                handle,
+                name +
+#if wxUSE_UNICODE
+                L'W'
+#else
+                'A'
+#endif
+               );
+    }

 
 

-// ----------------------------------------------------------------------------
-// wxLibrary
-// ----------------------------------------------------------------------------
+    void *GetSymbolAorW(const wxString& name) const
+    {
+        return RawGetSymbolAorW(m_handle, name);
+    }
+#endif // __WXMSW__

 
 

-class WXDLLEXPORT wxLibrary : public wxObject
-{
-public:
-    wxLibrary(wxDllType handle);
-    virtual ~wxLibrary();
+    // return all modules/shared libraries in the address space of this process
+    //
+    // returns an empty array if not implemented or an error occurred
+    static wxDynamicLibraryDetailsArray ListLoaded();

 
 

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

 
 

-    // Create the object whose classname is "name"
-    wxObject *CreateObject(const wxString& name);
+    // return name of wxWidgets plugin (adds compiler and version info
+    // to the filename):
+    static wxString
+    CanonicalizePluginName(const wxString& name,
+                           wxPluginCategory cat = wxDL_PLUGIN_GUI);

 
 

-protected:
-    void PrepareClasses(wxClassInfo *first);
+    // return plugin directory on platforms where it makes sense and empty
+    // string on others:
+    static wxString GetPluginsDirectory();

 
 

-    wxDllType m_handle;

 
 

-public:
-    wxHashTable classTable;
-};
+protected:
+    // common part of GetSymbol() and HasSymbol()
+    void *DoGetSymbol(const wxString& name, bool *success = 0) const;

 
 

-// ----------------------------------------------------------------------------
-// wxLibraries
-// ----------------------------------------------------------------------------
+#ifdef wxHAVE_DYNLIB_ERROR
+    // log the error after a dlxxx() function failure
+    static void Error();
+#endif // wxHAVE_DYNLIB_ERROR

 
 

-class WXDLLEXPORT wxLibraries
-{
-public:
-    wxLibraries();
-    ~wxLibraries();

 
 

-    // caller is responsible for deleting the returned pointer if !NULL
-    wxLibrary *LoadLibrary(const wxString& basename);
+    // platform specific shared lib suffix.
+    static const wxString ms_dllext;

 
 

-    wxObject *CreateObject(const wxString& name);
+    // the handle to DLL or NULL
+    wxDllType m_handle;

 
 

-protected:
-    wxList m_loaded;
+    // no copy ctor/assignment operators (or we'd try to unload the library
+    // twice)
+    DECLARE_NO_COPY_CLASS(wxDynamicLibrary)

 };
 
 };
 

-// ----------------------------------------------------------------------------
-// Global variables
-// ----------------------------------------------------------------------------
-
-extern wxLibraries wxTheLibraries;

 
 // ----------------------------------------------------------------------------
 // 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(); \
 }