src/gromacs/mdlib/sighandler.cpp

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  37 #include "gmxpre.h"
  38
  39 #include "sighandler.h"
  40
  41 #include "config.h"
  42
  43 #include <csignal>
  44 #include <cstdlib>
  45
  46 #include "gromacs/utility/fatalerror.h"
  47
  48 const char *gmx_stop_cond_name[] =
  49 {
  50     "None",
  51     "Stop at the next neighbor search step",
  52     "Stop at the next step",
  53     "Abort"
  54 };
  55
  56 /* these do not neccesarily match the stop condition, but are
  57    referred to in the signal handler. */
  58 static const char *gmx_signal_name[] =
  59 {
  60     "None",
  61     "INT",
  62     "TERM",
  63     "second INT/TERM",
  64     "remote INT/TERM",
  65     "remote second INT/TERM",
  66     "USR1",
  67     "Abort"
  68 };
  69
  70 static volatile sig_atomic_t stop_condition   = gmx_stop_cond_none;
  71 static volatile sig_atomic_t last_signal_name = 0;
  72
  73 static volatile sig_atomic_t usr_condition = 0;
  74
  75 void gmx_reset_stop_condition()
  76 {
  77     stop_condition   = gmx_stop_cond_none;
  78     // last_signal_name and usr_condition are left untouched by reset.
  79 }
  80
  81 static void signal_handler(int n)
  82 {
  83     switch (n)
  84     {
  85 /* windows doesn't do SIGINT correctly according to ANSI (yes, signals are in
  86    ANSI C89, and windows spawns a thread specifically to run the INT signal
  87    handler), but that doesn't matter for a simple signal handler like this. */
  88         case SIGTERM:
  89         case SIGINT:
  90             /* we explicitly set things up to allow this: */
  91             stop_condition++;
  92             if (n == SIGINT)
  93             {
  94                 last_signal_name = 1;
  95             }
  96             if (n == SIGTERM)
  97             {
  98                 last_signal_name = 2;
  99             }
 100             if (stop_condition == gmx_stop_cond_next)
 101             {
 102                 last_signal_name = 3;
 103             }
 104             if (stop_condition >= gmx_stop_cond_abort)
 105             {
 106                 abort();
 107             }
 108             break;
 109 #if HAVE_SIGUSR1
 110         case SIGUSR1:
 111             usr_condition = 1;
 112             break;
 113 #endif
 114         default:
 115             break;
 116     }
 117 }
 118
 119 static void gmx_signal(int signum)
 120 {
 121 #if HAVE_SIGACTION
 122     struct sigaction act;
 123     act.sa_handler = signal_handler;
 124     sigemptyset(&act.sa_mask);
 125     act.sa_flags = SA_RESTART;
 126     sigaction(signum, &act, nullptr);
 127 #else
 128     signal(signum, signal_handler);
 129 #endif
 130 }
 131
 132 void signal_handler_install()
 133 {
 134     if (getenv("GMX_NO_TERM") == nullptr)
 135     {
 136         if (debug)
 137         {
 138             fprintf(debug, "Installing signal handler for SIGTERM\n");
 139         }
 140         gmx_signal(SIGTERM);
 141     }
 142     if (getenv("GMX_NO_INT") == nullptr)
 143     {
 144         if (debug)
 145         {
 146             fprintf(debug, "Installing signal handler for SIGINT\n");
 147         }
 148         gmx_signal(SIGINT);
 149     }
 150 #if HAVE_SIGUSR1
 151     if (getenv("GMX_NO_USR1") == nullptr)
 152     {
 153         if (debug)
 154         {
 155             fprintf(debug, "Installing signal handler for SIGUSR1\n");
 156         }
 157         gmx_signal(SIGUSR1);
 158     }
 159 #endif
 160 }
 161
 162 gmx_stop_cond_t gmx_get_stop_condition()
 163 {
 164     return static_cast<gmx_stop_cond_t>(stop_condition);
 165 }
 166
 167 void gmx_set_stop_condition(gmx_stop_cond_t recvd_stop_cond)
 168 {
 169     if (recvd_stop_cond > stop_condition)
 170     {
 171         stop_condition = recvd_stop_cond;
 172         if (stop_condition == gmx_stop_cond_next_ns)
 173         {
 174             last_signal_name = 4;
 175         }
 176         if (stop_condition == gmx_stop_cond_next)
 177         {
 178             last_signal_name = 5;
 179         }
 180     }
 181 }
 182
 183 const char *gmx_get_signal_name()
 184 {
 185     return gmx_signal_name[last_signal_name];
 186 }
 187
 188 gmx_bool gmx_got_usr_signal()
 189 {
 190 #if HAVE_SIGUSR1
 191     gmx_bool ret = static_cast<gmx_bool>(usr_condition);
 192     usr_condition = 0;
 193     return ret;
 194 #else
 195     return FALSE;
 196 #endif
 197 }