00001 /* 00002 * semaphor.h 00003 * 00004 * Thread synchronisation semaphore class. 00005 * 00006 * Portable Windows Library 00007 * 00008 * Copyright (c) 1993-1998 Equivalence Pty. Ltd. 00009 * 00010 * The contents of this file are subject to the Mozilla Public License 00011 * Version 1.0 (the "License"); you may not use this file except in 00012 * compliance with the License. You may obtain a copy of the License at 00013 * http://www.mozilla.org/MPL/ 00014 * 00015 * Software distributed under the License is distributed on an "AS IS" 00016 * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See 00017 * the License for the specific language governing rights and limitations 00018 * under the License. 00019 * 00020 * The Original Code is Portable Windows Library. 00021 * 00022 * The Initial Developer of the Original Code is Equivalence Pty. Ltd. 00023 * 00024 * Portions are Copyright (C) 1993 Free Software Foundation, Inc. 00025 * All Rights Reserved. 00026 * 00027 * Contributor(s): ______________________________________. 00028 * 00029 * $Log: semaphor.h,v $ 00030 * Revision 1.18 2003/09/17 05:41:59 csoutheren 00031 * Removed recursive includes 00032 * 00033 * Revision 1.17 2003/09/17 01:18:02 csoutheren 00034 * Removed recursive include file system and removed all references 00035 * to deprecated coooperative threading support 00036 * 00037 * Revision 1.16 2002/09/16 01:08:59 robertj 00038 * Added #define so can select if #pragma interface/implementation is used on 00039 * platform basis (eg MacOS) rather than compiler, thanks Robert Monaghan. 00040 * 00041 * Revision 1.15 2002/01/23 04:26:36 craigs 00042 * Added copy constructors for PSemaphore, PMutex and PSyncPoint to allow 00043 * use of default copy constructors for objects containing instances of 00044 * these classes 00045 * 00046 * Revision 1.14 2001/11/23 00:55:18 robertj 00047 * Changed PWaitAndSignal so works inside const functions. 00048 * 00049 * Revision 1.13 2001/06/01 04:00:21 yurik 00050 * Removed dependency on obsolete function 00051 * 00052 * Revision 1.12 2001/05/22 12:49:32 robertj 00053 * Did some seriously wierd rewrite of platform headers to eliminate the 00054 * stupid GNU compiler warning about braces not matching. 00055 * 00056 * Revision 1.11 2001/04/23 00:34:29 robertj 00057 * Added ability for PWaitAndSignal to not wait on semaphore. 00058 * 00059 * Revision 1.10 2001/01/27 23:40:09 yurik 00060 * WinCE port-related - CreateEvent used instead of CreateSemaphore 00061 * 00062 * Revision 1.9 2000/12/19 22:20:26 dereks 00063 * Add video channel classes to connect to the PwLib PVideoInputDevice class. 00064 * Add PFakeVideoInput class to generate test images for video. 00065 * 00066 * Revision 1.8 1999/03/09 02:59:50 robertj 00067 * Changed comments to doc++ compatible documentation. 00068 * 00069 * Revision 1.7 1999/02/16 08:11:10 robertj 00070 * MSVC 6.0 compatibility changes. 00071 * 00072 * Revision 1.6 1998/11/19 05:17:37 robertj 00073 * Added PWaitAndSignal class for easier mutexing. 00074 * 00075 * Revision 1.5 1998/09/23 06:21:19 robertj 00076 * Added open source copyright license. 00077 * 00078 * Revision 1.4 1998/03/20 03:16:11 robertj 00079 * Added special classes for specific sepahores, PMutex and PSyncPoint. 00080 * 00081 * Revision 1.3 1995/12/10 11:34:50 robertj 00082 * Fixed incorrect order of parameters in semaphore constructor. 00083 * 00084 * Revision 1.2 1995/11/21 11:49:42 robertj 00085 * Added timeout on semaphore wait. 00086 * 00087 * Revision 1.1 1995/08/01 21:41:24 robertj 00088 * Initial revision 00089 * 00090 */ 00091 00092 #ifndef _PSEMAPHORE 00093 #define _PSEMAPHORE 00094 00095 #ifdef P_USE_PRAGMA 00096 #pragma interface 00097 #endif 00098 00099 #include <limits.h> 00100 00101 00120 class PWaitAndSignal { 00121 public: 00126 PWaitAndSignal( 00127 const PSemaphore & sem, 00128 BOOL wait = TRUE 00129 ); 00134 ~PWaitAndSignal(); 00135 00136 protected: 00137 PSemaphore & semaphore; 00138 }; 00139 00140 00174 class PSemaphore : public PObject 00175 { 00176 PCLASSINFO(PSemaphore, PObject); 00177 00178 public: 00185 PSemaphore( 00186 unsigned initial, 00187 unsigned maximum 00188 ); 00189 00192 PSemaphore(const PSemaphore &); 00193 00197 ~PSemaphore(); 00199 00205 virtual void Wait(); 00206 00213 virtual BOOL Wait( 00214 const PTimeInterval & timeout // Amount of time to wait for semaphore. 00215 ); 00216 00221 virtual void Signal(); 00222 00229 virtual BOOL WillBlock() const; 00231 00232 private: 00233 PSemaphore & operator=(const PSemaphore &) { return *this; } 00234 00235 00236 // Include platform dependent part of class 00237 #ifdef _WIN32 00238 #include "msos/ptlib/semaphor.h" 00239 #else 00240 #include "unix/ptlib/semaphor.h" 00241 #endif 00242 }; 00243 00244 #endif 00245 00246 // End Of File ///////////////////////////////////////////////////////////////