hvirtual/guicast/condition.C

   1 #include "bcsignals.h"
   2 #include "condition.h"
   3
   4 #include <errno.h>
   5 #include <sys/time.h>
   6
   7 Condition::Condition(int init_value, char *title)
   8 {
   9         this->title = title;
  10         pthread_mutex_init(&mutex, 0);
  11         pthread_cond_init(&cond, NULL);
  12         this->value = this->init_value = init_value;
  13 }
  14
  15 Condition:: ~Condition()
  16 {
  17     pthread_cond_destroy(&cond);
  18     pthread_mutex_destroy(&mutex);
  19         UNSET_ALL_LOCKS(this);
  20 }
  21
  22 void Condition::reset()
  23 {
  24     pthread_cond_destroy(&cond);
  25     pthread_mutex_destroy(&mutex);
  26         pthread_mutex_init(&mutex, 0);
  27         pthread_cond_init(&cond, NULL);
  28         value = init_value;
  29 }
  30
  31 void Condition::lock(char *location)
  32 {
  33         SET_LOCK(this, title, location);
  34     pthread_mutex_lock(&mutex);
  35     while(value <= 0) pthread_cond_wait(&cond, &mutex);
  36         value--;
  37     pthread_mutex_unlock(&mutex);
  38 }
  39
  40 void Condition::unlock()
  41 {
  42         UNSET_LOCK(this);
  43     pthread_mutex_lock(&mutex);
  44     value++;
  45     pthread_cond_signal(&cond);
  46     pthread_mutex_unlock(&mutex);
  47 }
  48
  49 int Condition::timed_lock(int microseconds, char *location)
  50 {
  51     struct timeval now;
  52     struct timespec timeout;
  53     int result = 0;
  54
  55         SET_LOCK(this, title, location);
  56     pthread_mutex_lock(&mutex);
  57     gettimeofday(&now, 0);
  58     timeout.tv_sec = now.tv_sec + microseconds / 1000000;
  59     timeout.tv_nsec = now.tv_usec * 1000 + (microseconds % 1000000) * 1000;
  60
  61     while(value <= 0 && result != ETIMEDOUT)
  62         {
  63                 result = pthread_cond_timedwait(&cond, &mutex, &timeout);
  64     }
  65
  66     if(result == ETIMEDOUT)
  67         {
  68                 result = 1;
  69     }
  70         else
  71         {
  72                 value--;
  73                 result = 0;
  74     }
  75     pthread_mutex_unlock(&mutex);
  76         return result;
  77 }
  78
  79
  80 int Condition::get_value()
  81 {
  82         return value;
  83 }