git.m6w6.name Git - m6w6/libmemcached/blob - libtest/signal.cc

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   2  *
   3  *  uTest, libtest
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  36
  37 #include <libtest/common.h>
  38
  39 #include <csignal>
  40
  41 #include <libtest/signal.h>
  42
  43 using namespace libtest;
  44
  45 #define MAGIC_MEMORY 123569
  46
  47 bool SignalThread::is_shutdown()
  48 {
  49   bool ret;
  50   pthread_mutex_lock(&shutdown_mutex);
  51   ret= bool(__shutdown != SHUTDOWN_RUNNING);
  52   pthread_mutex_unlock(&shutdown_mutex);
  53
  54   return ret;
  55 }
  56
  57 void SignalThread::set_shutdown(shutdown_t arg)
  58 {
  59   pthread_mutex_lock(&shutdown_mutex);
  60   __shutdown= arg;
  61   pthread_mutex_unlock(&shutdown_mutex);
  62
  63   if (arg == SHUTDOWN_GRACEFUL)
  64   {
  65     pthread_kill(thread, SIGUSR2);
  66
  67     void *retval;
  68     pthread_join(thread, &retval);
  69   }
  70 }
  71
  72 shutdown_t SignalThread::get_shutdown()
  73 {
  74   shutdown_t local;
  75   pthread_mutex_lock(&shutdown_mutex);
  76   local= __shutdown;
  77   pthread_mutex_unlock(&shutdown_mutex);
  78
  79   return local;
  80 }
  81
  82 void SignalThread::post()
  83 {
  84   sem_post(&lock);
  85 }
  86
  87 void SignalThread::test()
  88 {
  89   assert(magic_memory == MAGIC_MEMORY);
  90   if (not getenv("LIBTEST_IN_GDB"))
  91   {
  92     assert(sigismember(&set, SIGABRT));
  93     assert(sigismember(&set, SIGQUIT));
  94     assert(sigismember(&set, SIGINT));
  95   }
  96   assert(sigismember(&set, SIGUSR2));
  97 }
  98
  99 extern "C" {
 100
 101 static void *sig_thread(void *arg)
 102 {
 103   SignalThread *context= (SignalThread*)arg;
 104
 105   context->test();
 106   context->post();
 107
 108   while (context->get_shutdown() == SHUTDOWN_RUNNING)
 109   {
 110     int sig;
 111
 112     if (context->wait(sig) == -1)
 113     {
 114       Error << "sigwait() returned errno:" << strerror(errno);
 115       continue;
 116     }
 117
 118     switch (sig)
 119     {
 120     case SIGABRT:
 121     case SIGUSR2:
 122     case SIGINT:
 123     case SIGQUIT:
 124       if (context->is_shutdown() == false)
 125       {
 126         Error << "Signal handling thread got signal " <<  strsignal(sig);
 127         context->set_shutdown(SHUTDOWN_FORCED);
 128       }
 129       break;
 130
 131     default:
 132       Error << "Signal handling thread got unexpected signal " <<  strsignal(sig);
 133       break;
 134     }
 135   }
 136
 137   return NULL;
 138 }
 139
 140 }
 141
 142 SignalThread::SignalThread() :
 143   magic_memory(MAGIC_MEMORY)
 144 {
 145   pthread_mutex_init(&shutdown_mutex, NULL);
 146   sigemptyset(&set);
 147   if (not getenv("LIBTEST_IN_GDB"))
 148   {
 149     sigaddset(&set, SIGABRT);
 150     sigaddset(&set, SIGQUIT);
 151     sigaddset(&set, SIGINT);
 152   }
 153
 154   sigaddset(&set, SIGUSR2);
 155
 156   sem_init(&lock, 0, 0);
 157 }
 158
 159
 160 bool SignalThread::setup()
 161 {
 162   set_shutdown(SHUTDOWN_RUNNING);
 163
 164   sigset_t old_set;
 165   sigemptyset(&old_set);
 166   pthread_sigmask(SIG_BLOCK, NULL, &old_set);
 167
 168   if (sigismember(&old_set, SIGQUIT))
 169   {
 170     Error << strsignal(SIGQUIT) << " has been previously set.";
 171   }
 172   if (sigismember(&old_set, SIGINT))
 173   {
 174     Error << strsignal(SIGINT) << " has been previously set.";
 175   }
 176   if (sigismember(&old_set, SIGUSR2))
 177   {
 178     Error << strsignal(SIGUSR2) << " has been previously set.";
 179   }
 180
 181   int error;
 182   if ((error= pthread_sigmask(SIG_BLOCK, &set, NULL)) != 0)
 183   {
 184     Error << "pthread_sigmask() died during pthread_sigmask(" << strerror(error) << ")";
 185     return false;
 186   }
 187
 188   if ((error= pthread_create(&thread, NULL, &sig_thread, this)) != 0)
 189   {
 190     Error << "pthread_create() died during pthread_create(" << strerror(error) << ")";
 191     return false;
 192   }
 193
 194   sem_wait(&lock);
 195
 196   return true;
 197 }