lib/libmthread/event.c

   1 #include <minix/mthread.h>
   2 #include "global.h"
   3
   4 /*===========================================================================*
   5  *                              mthread_event_init                           *
   6  *===========================================================================*/
   7 int mthread_event_init(event)
   8 mthread_event_t *event; /* The event to be initialized */
   9 {
  10 /* Initialize an event object.
  11  */
  12   int r;
  13
  14   if (!event)
  15         return EINVAL;
  16
  17   r = mthread_mutex_init(&event->mutex, NULL);
  18   if (r != 0)
  19         return r;
  20
  21   r = mthread_cond_init(&event->cond, NULL);
  22   if (r != 0)
  23         mthread_mutex_destroy(&event->mutex);
  24
  25   return r;
  26 }
  27
  28
  29 /*===========================================================================*
  30  *                              mthread_event_destroy                        *
  31  *===========================================================================*/
  32 int mthread_event_destroy(event)
  33 mthread_event_t *event; /* The event to be destroyed */
  34 {
  35 /* Destroy an event object.
  36  */
  37   int r;
  38
  39   if (!event)
  40         return EINVAL;
  41
  42   r = mthread_cond_destroy(&event->cond);
  43   if (r != 0)
  44         return r;
  45
  46   return mthread_mutex_destroy(&event->mutex);
  47 }
  48
  49 /*===========================================================================*
  50  *                              mthread_event_wait                           *
  51  *===========================================================================*/
  52 int mthread_event_wait(event)
  53 mthread_event_t *event; /* The event to be waited on */
  54 {
  55 /* Wait for an event, blocking the current thread in the process.
  56  */
  57   int r;
  58
  59   if (!event)
  60         return EINVAL;
  61
  62   r = mthread_mutex_lock(&event->mutex);
  63   if (r != 0)
  64         return r;
  65
  66   r = mthread_cond_wait(&event->cond, &event->mutex);
  67   if (r != 0) {
  68         mthread_mutex_unlock(&event->mutex);
  69         return r;
  70   }
  71
  72   return mthread_mutex_unlock(&event->mutex);
  73 }
  74
  75 /*===========================================================================*
  76  *                              mthread_event_fire                           *
  77  *===========================================================================*/
  78 int mthread_event_fire(event)
  79 mthread_event_t *event; /* The event to be fired */
  80 {
  81 /* Fire an event, waking up any thread blocked on it.
  82 */
  83   int r;
  84
  85   if (!event)
  86         return EINVAL;
  87
  88   r = mthread_mutex_lock(&event->mutex);
  89   if (r != 0)
  90         return r;
  91
  92   r = mthread_cond_signal(&event->cond);
  93   if (r != 0) {
  94         mthread_mutex_unlock(&event->mutex);
  95         return r;
  96   }
  97
  98   return mthread_mutex_unlock(&event->mutex);
  99 }
 100
 101
 102 /*===========================================================================*
 103  *                              mthread_event_fire_all                       *
 104  *===========================================================================*/
 105 int mthread_event_fire_all(event)
 106 mthread_event_t *event; /* The event to be fired */
 107 {
 108 /* Fire an event, waking up any thread blocked on it.
 109 */
 110   int r;
 111
 112   if (!event)
 113         return EINVAL;
 114
 115   r = mthread_mutex_lock(&event->mutex);
 116   if (r != 0)
 117         return r;
 118
 119   r = mthread_cond_broadcast(&event->cond);
 120   if (r != 0) {
 121         mthread_mutex_unlock(&event->mutex);
 122         return r;
 123   }
 124
 125   return mthread_mutex_unlock(&event->mutex);
 126 }