| /*---------------------------------------------------------------------------*\ | |
| ========= | | |
| \\ / F ield | OpenFOAM: The Open Source CFD Toolbox | |
| \\ / O peration | Website: https://openfoam.org | |
| \\ / A nd | Copyright (C) 2011-2020 OpenFOAM Foundation | |
| \\/ M anipulation | | |
| ------------------------------------------------------------------------------- | |
| License | |
| This file is part of OpenFOAM. | |
| OpenFOAM is free software: you can redistribute it and/or modify it | |
| under the terms of the GNU General Public License as published by | |
| the Free Software Foundation, either version 3 of the License, or | |
| (at your option) any later version. | |
| OpenFOAM is distributed in the hope that it will be useful, but WITHOUT | |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| for more details. | |
| You should have received a copy of the GNU General Public License | |
| along with OpenFOAM. If not, see <http://www.gnu.org/licenses/>. | |
| Class | |
| Foam::timer | |
| Description | |
| Implements a timeout mechanism via sigalarm. | |
| Example usage: | |
| \code | |
| timer myTimer(5); // 5 sec | |
| .. | |
| if (timedOut(myTimer)) | |
| { | |
| // timed out | |
| } | |
| else | |
| { | |
| // do something possible blocking | |
| } | |
| \endcode | |
| Constructor set signal handler on sigalarm and alarm(). Destructor | |
| clears these. | |
| timedOut is macro because setjmp can't be in member function of timer. | |
| ?something to do with stack frames. | |
| Warning | |
| The setjmp restores complete register state so including local vars | |
| held in regs. So if in blocking part something gets calced in a stack | |
| based variable make sure it is declared 'volatile'. | |
| SourceFiles | |
| timer.C | |
| \*---------------------------------------------------------------------------*/ | |
| // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // | |
| //- Check it a timeout has occurred | |
| // keep setjmp in same stack frame so no function calls | |
| namespace Foam | |
| { | |
| /*---------------------------------------------------------------------------*\ | |
| Class timer Declaration | |
| \*---------------------------------------------------------------------------*/ | |
| class timer | |
| { | |
| // Private Data | |
| //- Old signal masks | |
| static struct sigaction oldAction_; | |
| //- Old alarm() value | |
| static unsigned int oldTimeOut_; | |
| // Private Member Functions | |
| //- Alarm handler | |
| static void signalHandler(int); | |
| public: | |
| // Public data | |
| //- Declare name of the class and its debug switch | |
| ClassName("timer"); | |
| //- Current time out value. Needed by macro timedOut | |
| unsigned int newTimeOut_; | |
| //- State for setjmp. Needed by macro timedOut | |
| static jmp_buf envAlarm; | |
| // Constructors | |
| //- Construct from components. | |
| // newTimeOut=0 makes it do nothing. | |
| timer(const unsigned int newTimeOut); | |
| //- Destructor | |
| ~timer(); | |
| }; | |
| // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // | |
| } // End namespace Foam | |
| // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * // | |
| // ************************************************************************* // | |