src/gmxlib/sighandler.c

   1 /*
   2  *
   3  *                This source code is part of
   4  *
   5  *                 G   R   O   M   A   C   S
   6  *
   7  *          GROningen MAchine for Chemical Simulations
   8  *
   9  *                        VERSION 3.2.0
  10  * Written by David van der Spoel, Erik Lindahl, Berk Hess, and others.
  11  * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
  12  * Copyright (c) 2001-2004, The GROMACS development team,
  13  * check out http://www.gromacs.org for more information.
  14
  15  * This program is free software; you can redistribute it and/or
  16  * modify it under the terms of the GNU General Public License
  17  * as published by the Free Software Foundation; either version 2
  18  * of the License, or (at your option) any later version.
  19  *
  20  * If you want to redistribute modifications, please consider that
  21  * scientific software is very special. Version control is crucial -
  22  * bugs must be traceable. We will be happy to consider code for
  23  * inclusion in the official distribution, but derived work must not
  24  * be called official GROMACS. Details are found in the README & COPYING
  25  * files - if they are missing, get the official version at www.gromacs.org.
  26  *
  27  * To help us fund GROMACS development, we humbly ask that you cite
  28  * the papers on the package - you can find them in the top README file.
  29  *
  30  * For more info, check our website at http://www.gromacs.org
  31  *
  32  * And Hey:
  33  * GROwing Monsters And Cloning Shrimps
  34  */
  35 #ifdef HAVE_CONFIG_H
  36 #include <config.h>
  37 #endif
  38
  39 #include "typedefs.h"
  40 #include "gmx_fatal.h"
  41 #include "sighandler.h"
  42
  43 /* The following two variables and the signal_handler function
  44  * are used from md.c and pme.c as well
  45  *
  46  * Do not fear these global variables: they represent inherently process-global
  47  * information that needs to be shared across threads
  48  */
  49
  50
  51 /* we got a signal to stop in the next step: */
  52 volatile sig_atomic_t bGotStopNextStepSignal=FALSE;
  53 /* we got a signal to stop in the next neighbour search step: */
  54 volatile sig_atomic_t bGotStopNextNSStepSignal=FALSE;
  55
  56 /* our names for the handled signals. These must match the number given
  57    in signal_handler. */
  58 const char *signal_name[] =
  59 {
  60     "TERM",
  61     "INT",
  62     "second INT"
  63 };
  64
  65 /* the last signal received, according to the numbering
  66    we use in signal_name */
  67 volatile sig_atomic_t last_signal_number_recvd=-1;
  68
  69 RETSIGTYPE signal_handler(int n)
  70 {
  71     switch (n) {
  72         case SIGTERM:
  73             bGotStopNextStepSignal = TRUE;
  74             last_signal_number_recvd = 0;
  75             break;
  76 /* windows doesn't do SIGINT correctly according to ANSI (yes, signals are in
  77    ANSI C89, and windows spawns a thread specifically to run the INT signal
  78    handler), but that doesn't matter for a simple signal handler like this. */
  79         case SIGINT:
  80             if (!bGotStopNextNSStepSignal)
  81             {
  82                 bGotStopNextNSStepSignal = TRUE;
  83                 last_signal_number_recvd = 1;
  84             }            else if (!bGotStopNextStepSignal)
  85             {
  86                 bGotStopNextStepSignal = TRUE;
  87                 last_signal_number_recvd = 2;
  88             }
  89             else
  90                 abort();
  91             break;
  92     }
  93 }
  94
  95
  96 void signal_handler_install(void)
  97 {
  98     if (getenv("GMX_NO_TERM") == NULL)
  99     {
 100         if (debug)
 101         {
 102             fprintf(debug,"Installing signal handler for SIGTERM\n");
 103         }
 104         signal(SIGTERM,signal_handler);
 105     }
 106     if (getenv("GMX_NO_INT") == NULL)
 107     {
 108         if (debug)
 109         {
 110             fprintf(debug,"Installing signal handler for SIGINT\n");
 111         }
 112         signal(SIGINT,signal_handler);
 113     }
 114
 115 }
 116
 117
 118