1 /* 2 * Copyright (c) 2009, 2011, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 #ifndef DLLUTIL_H 27 #define DLLUTIL_H 28 29 #include <tchar.h> 30 #include <windows.h> 31 32 /** 33 * Utility class to handle dynamically loadable libraries. 34 * 35 * NOTE: THIS CLASS IS NOT THREAD-SAFE! 36 */ 37 class DllUtil { 38 public: 39 class Exception {}; 40 class LibraryUnavailableException : public Exception {}; 41 class FunctionUnavailableException : public Exception {}; 42 43 FARPROC GetProcAddress(LPCSTR name); 44 45 protected: DllUtil(const char * name)46 DllUtil(const char * name) : name(name), module(NULL) {} 47 virtual ~DllUtil(); 48 49 HMODULE GetModule(); 50 51 template <class FunctionType> class Function { 52 public: Function(DllUtil * dll,LPCSTR name)53 Function(DllUtil * dll, LPCSTR name) : 54 dll(dll), name(name), function(NULL) {} 55 operator()56 inline FunctionType operator () () { 57 if (!function) { 58 function = (FunctionType)dll->GetProcAddress(name); 59 } 60 return function; 61 } 62 63 private: 64 DllUtil * const dll; 65 LPCSTR name; 66 67 FunctionType function; 68 }; 69 70 private: 71 const char * const name; 72 HMODULE module; 73 }; 74 75 class DwmAPI : public DllUtil { 76 public: 77 // See DWMWINDOWATTRIBUTE enum in dwmapi.h 78 static const DWORD DWMWA_EXTENDED_FRAME_BOUNDS = 9; 79 80 static HRESULT DwmIsCompositionEnabled(BOOL * pfEnabled); 81 static HRESULT DwmGetWindowAttribute(HWND hwnd, DWORD dwAttribute, 82 PVOID pvAttribute, DWORD cbAttribute); 83 84 private: 85 static DwmAPI & GetInstance(); 86 DwmAPI(); 87 88 typedef HRESULT (WINAPI *DwmIsCompositionEnabledType)(BOOL*); 89 Function<DwmIsCompositionEnabledType> DwmIsCompositionEnabledFunction; 90 91 typedef HRESULT (WINAPI *DwmGetWindowAttributeType)(HWND hwnd, DWORD dwAttribute, 92 PVOID pvAttribute, DWORD cbAttribute); 93 Function<DwmGetWindowAttributeType> DwmGetWindowAttributeFunction; 94 }; 95 96 #endif // DLLUTIL_H 97 98