Added event handler macro

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

diff --git a/include/wx/dynlib.h b/include/wx/dynlib.h
index 4d5f948628c403c40687be2b64ec24283110b319..0fabb058bf43a96a198697d8c9d710eb983b6570 100644 (file)
--- a/include/wx/dynlib.h
+++ b/include/wx/dynlib.h
@@ -75,6 +75,8 @@ enum wxDLFlags
     wxDL_NOSHARE    = 0x00000010,   // load new DLL, don't reuse already loaded
                                     // (only for wxPluginManager)
 
     wxDL_NOSHARE    = 0x00000010,   // load new DLL, don't reuse already loaded
                                     // (only for wxPluginManager)
 

+    wxDL_QUIET      = 0x00000020,   // don't log an error if failed to load
+

     wxDL_DEFAULT    = wxDL_NOW      // default flags correspond to Win32
 };
 
     wxDL_DEFAULT    = wxDL_NOW      // default flags correspond to Win32
 };
 


@@ -105,6 +107,63 @@ enum wxPluginCategory
 #define wxDYNLIB_FUNCTION(type, name, dynlib) \
     type pfn ## name = (type)(dynlib).GetSymbol(_T(#name))
 
 #define wxDYNLIB_FUNCTION(type, name, dynlib) \
     type pfn ## name = (type)(dynlib).GetSymbol(_T(#name))
 

+
+// a more convenient function replacing wxDYNLIB_FUNCTION above
+//
+// it uses the convention that the type of the function is its name suffixed
+// with "_t" but it doesn't define a variable but just assigns the loaded value
+// to it and also allows to pass it the prefix to be used instead of hardcoding
+// "pfn" (the prefix can be "m_" or "gs_pfn" or whatever)
+//
+// notice that this function doesn't generate error messages if the symbol
+// couldn't be loaded, the caller should generate the appropriate message
+#define wxDL_INIT_FUNC(pfx, name, dynlib) \
+    pfx ## name = (name ## _t)(dynlib).RawGetSymbol(#name)
+
+#ifdef __WXMSW__
+
+// same as wxDL_INIT_FUNC() but appends 'A' or 'W' to the function name, see
+// wxDynamicLibrary::GetSymbolAorW()
+#define wxDL_INIT_FUNC_AW(pfx, name, dynlib) \
+    pfx ## name = (name ## _t)(dynlib).GetSymbolAorW(#name)
+
+#endif // __WXMSW__
+
+// the following macros can be used to redirect a whole library to a class and
+// check at run-time if the library is present and contains all required
+// methods
+//
+// notice that they are supposed to be used inside a class which has "m_ok"
+// member variable indicating if the library had been successfully loaded
+
+// helper macros constructing the name of the variable storing the function
+// pointer and the name of its type from the function name
+#define wxDL_METHOD_NAME(name) m_pfn ## name
+#define wxDL_METHOD_TYPE(name) name ## _t
+
+// parameters are:
+//  - rettype: return type of the function, e.g. "int"
+//  - name: name of the function, e.g. "foo"
+//  - args: function signature in parentheses, e.g. "(int x, int y)"
+//  - argnames: the names of the parameters in parentheses, e.g. "(x, y)"
+//  - defret: the value to return if the library wasn't successfully loaded
+#define wxDL_METHOD_DEFINE( rettype, name, args, argnames, defret ) \
+    typedef rettype (* wxDL_METHOD_TYPE(name)) args ; \
+    wxDL_METHOD_TYPE(name) wxDL_METHOD_NAME(name); \
+    rettype name args \
+        { return m_ok ? wxDL_METHOD_NAME(name) argnames : defret; }
+
+#define wxDL_VOIDMETHOD_DEFINE( name, args, argnames ) \
+    typedef void (* wxDL_METHOD_TYPE(name)) args ; \
+    wxDL_METHOD_TYPE(name) wxDL_METHOD_NAME(name); \
+    void name args \
+        { if ( m_ok ) wxDL_METHOD_NAME(name) argnames ; }
+
+#define wxDL_METHOD_LOAD(lib, name) \
+    wxDL_METHOD_NAME(name) = \
+        (wxDL_METHOD_TYPE(name)) lib.GetSymbol(#name, &m_ok); \
+    if ( !m_ok ) return false
+

 // ----------------------------------------------------------------------------
 // wxDynamicLibraryDetails: contains details about a loaded wxDynamicLibrary
 // ----------------------------------------------------------------------------
 // ----------------------------------------------------------------------------
 // wxDynamicLibraryDetails: contains details about a loaded wxDynamicLibrary
 // ----------------------------------------------------------------------------