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     if (pthread_kill(thread, SIGUSR2) == 0)
  66     {
  67       void *retval;
  68       pthread_join(thread, &retval);
  69     }
  70   }
  71 }
  72
  73 shutdown_t SignalThread::get_shutdown()
  74 {
  75   shutdown_t local;
  76   pthread_mutex_lock(&shutdown_mutex);
  77   local= __shutdown;
  78   pthread_mutex_unlock(&shutdown_mutex);
  79
  80   return local;
  81 }
  82
  83 void SignalThread::post()
  84 {
  85   sem_post(&lock);
  86 }
  87
  88 void SignalThread::test()
  89 {
  90   assert(magic_memory == MAGIC_MEMORY);
  91   if (not getenv("LIBTEST_IN_GDB"))
  92   {
  93     assert(sigismember(&set, SIGABRT));
  94     assert(sigismember(&set, SIGQUIT));
  95     assert(sigismember(&set, SIGINT));
  96   }
  97   assert(sigismember(&set, SIGUSR2));
  98 }
  99
 100 SignalThread::~SignalThread()
 101 {
 102   if (pthread_equal(thread, pthread_self()) != 0 and (pthread_kill(thread, 0) == ESRCH) == true)
 103   {
 104     void *retval;
 105     pthread_join(thread, &retval);
 106   }
 107   sem_destroy(&lock);
 108 }
 109
 110 extern "C" {
 111
 112 static void *sig_thread(void *arg)
 113 {
 114   SignalThread *context= (SignalThread*)arg;
 115
 116   context->test();
 117   context->post();
 118
 119   while (context->get_shutdown() == SHUTDOWN_RUNNING)
 120   {
 121     int sig;
 122
 123     if (context->wait(sig) == -1)
 124     {
 125       Error << "sigwait() returned errno:" << strerror(errno);
 126       continue;
 127     }
 128
 129     switch (sig)
 130     {
 131     case SIGABRT:
 132     case SIGUSR2:
 133     case SIGINT:
 134     case SIGQUIT:
 135       if (context->is_shutdown() == false)
 136       {
 137         context->set_shutdown(SHUTDOWN_FORCED);
 138       }
 139       break;
 140
 141     default:
 142       Error << "Signal handling thread got unexpected signal " <<  strsignal(sig);
 143       break;
 144     }
 145   }
 146
 147   return NULL;
 148 }
 149
 150 }
 151
 152 SignalThread::SignalThread() :
 153   magic_memory(MAGIC_MEMORY),
 154   thread(pthread_self())
 155 {
 156   pthread_mutex_init(&shutdown_mutex, NULL);
 157   sigemptyset(&set);
 158   if (not getenv("LIBTEST_IN_GDB"))
 159   {
 160     sigaddset(&set, SIGABRT);
 161     sigaddset(&set, SIGQUIT);
 162     sigaddset(&set, SIGINT);
 163   }
 164
 165   sigaddset(&set, SIGUSR2);
 166
 167   sem_init(&lock, 0, 0);
 168 }
 169
 170
 171 bool SignalThread::setup()
 172 {
 173   set_shutdown(SHUTDOWN_RUNNING);
 174
 175   sigset_t old_set;
 176   sigemptyset(&old_set);
 177   pthread_sigmask(SIG_BLOCK, NULL, &old_set);
 178
 179   if (sigismember(&old_set, SIGQUIT))
 180   {
 181     Error << strsignal(SIGQUIT) << " has been previously set.";
 182   }
 183   if (sigismember(&old_set, SIGINT))
 184   {
 185     Error << strsignal(SIGINT) << " has been previously set.";
 186   }
 187   if (sigismember(&old_set, SIGUSR2))
 188   {
 189     Error << strsignal(SIGUSR2) << " has been previously set.";
 190   }
 191
 192   int error;
 193   if ((error= pthread_sigmask(SIG_BLOCK, &set, NULL)) != 0)
 194   {
 195     Error << "pthread_sigmask() died during pthread_sigmask(" << strerror(error) << ")";
 196     return false;
 197   }
 198
 199   if ((error= pthread_create(&thread, NULL, &sig_thread, this)) != 0)
 200   {
 201     Error << "pthread_create() died during pthread_create(" << strerror(error) << ")";
 202     return false;
 203   }
 204
 205   sem_wait(&lock);
 206
 207   return true;
 208 }