State.cxx
Go to the documentation of this file.00001 /* ======================================================================== 00002 * Copyright (C) 2005 Graz University of Technology 00003 * 00004 * This framework is free software; you can redistribute it and/or modify 00005 * it under the terms of the GNU General Public License as published by 00006 * the Free Software Foundation; either version 2 of the License, or 00007 * (at your option) any later version. 00008 * 00009 * This framework is distributed in the hope that it will be useful, 00010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 00011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00012 * GNU General Public License for more details. 00013 * 00014 * You should have received a copy of the GNU General Public License 00015 * along with this framework; if not, write to the Free Software 00016 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 00017 * 00018 * For further information please contact Denis Kalkofen under 00019 * <kalkofen@icg.tu-graz.ac.at> or write to Denis Kalkofen, 00020 * Graz University of Technology, Inffeldgasse 16a, A8010 Graz, 00021 * Austria. 00022 * ======================================================================== 00023 * PROJECT: OpenVideo 00024 * ======================================================================== */ 00034 #include <openvideo/State.h> 00035 #include <ace/Thread_Mutex.h> 00036 00037 00038 namespace openvideo { 00039 00040 00041 Buffer::Buffer() : buffer(NULL) 00042 { 00043 lockCtr = 0; 00044 updateCtr = 0; 00045 mutex = new ACE_Thread_Mutex; 00046 width = height = 0; 00047 format = FORMAT_UNKNOWN; 00048 } 00049 00050 00051 Buffer::~Buffer() 00052 { 00053 delete mutex; 00054 mutex = NULL; 00055 } 00056 00057 00058 void 00059 Buffer::lock() 00060 { 00061 mutex->acquire(); 00062 lockCtr++; 00063 mutex->release(); 00064 } 00065 00066 00067 void 00068 Buffer::unlock() 00069 { 00070 mutex->acquire(); 00071 lockCtr--; 00072 assert(lockCtr>=0); 00073 mutex->release(); 00074 } 00075 00076 00077 void 00078 State::unlockAllBuffers() 00079 { 00080 for(size_t i=0; i<buffers.size(); i++) 00081 buffers[i]->unlock(); 00082 } 00083 00084 00085 Buffer* 00086 State::findFreeBuffer() 00087 { 00088 for(size_t i=0; i<buffers.size(); i++) 00089 if(!buffers[i]->isLocked()) 00090 return buffers[i]; 00091 00092 return NULL; 00093 } 00094 00095 00096 int 00097 State::getNumLockedBuffers() const 00098 { 00099 int c=0; 00100 00101 for(size_t i=0; i<buffers.size(); i++) 00102 if(buffers[i]->isLocked()) 00103 c++; 00104 00105 return c; 00106 } 00107 00108 00109 BufferSynchronizer::BufferSynchronizer() 00110 { 00111 buffer = NULL; 00112 mutex = new ACE_Thread_Mutex; 00113 } 00114 00115 00116 BufferSynchronizer::~BufferSynchronizer() 00117 { 00118 if(buffer) 00119 buffer->unlock(); 00120 buffer = NULL; 00121 00122 delete mutex; 00123 mutex = NULL; 00124 } 00125 00126 00127 void 00128 BufferSynchronizer::assign(Buffer* newBuffer) 00129 { 00130 if(buffer == newBuffer) 00131 return; 00132 00133 mutex->acquire(); 00134 00135 Buffer* oldBuffer = buffer; 00136 if(newBuffer) 00137 newBuffer->lock(); 00138 buffer = newBuffer; 00139 if(oldBuffer) 00140 oldBuffer->unlock(); 00141 00142 mutex->release(); 00143 } 00144 00145 00146 Buffer* 00147 BufferSynchronizer::getLocked() 00148 { 00149 if(!buffer) 00150 return NULL; 00151 00152 Buffer* retBuffer; 00153 00154 mutex->acquire(); 00155 00156 retBuffer = buffer; 00157 retBuffer->lock(); 00158 00159 mutex->release(); 00160 00161 return retBuffer; 00162 } 00163 00164 00165 } // namespace openvideo