refcount.c

   1 #include "refcount.h"
   2
   3 void refcount_ini(Refcount *refcount, void *obj, Transformer del)
   4 {
   5         refcount->obj = obj;
   6         refcount->del = del;
   7         refcount->cnt = 1;
   8         pthread_mutex_init(&refcount->mtx, NULL);
   9 }
  10
  11 void refcount_dst(Refcount *refcount)
  12 {
  13         pthread_mutex_destroy(&refcount->mtx);
  14 }
  15
  16 void *refcount_inc(void *refcount)
  17 {
  18         Refcount *rc = refcount;
  19
  20         pthread_mutex_lock(&rc->mtx);
  21         rc->cnt++;
  22         pthread_mutex_unlock(&rc->mtx);
  23         return rc;
  24 }
  25
  26 void *refcount_grb(void *refcount)
  27 {
  28         return refcount_obj(refcount_inc(refcount));
  29 }
  30
  31 void *refcount_drp(void *refcount)
  32 {
  33         Refcount *rc = refcount;
  34
  35         pthread_mutex_lock(&rc->mtx);
  36         unsigned short count = --rc->cnt;
  37         pthread_mutex_unlock(&rc->mtx);
  38
  39         if (! count)
  40                 return rc->del(rc->obj);
  41
  42         return rc->obj;
  43 }
  44
  45 void *refcount_obj(void *refcount)
  46 {
  47         return ((Refcount *) refcount)->obj;
  48 }