include/lttng/ref-internal.hpp

   1 #ifndef LTTNG_REF_INTERNAL_H
   2 #define LTTNG_REF_INTERNAL_H
   3
   4 /*
   5  * LTTng - Non thread-safe reference counting
   6  *
   7  * Copyright 2013, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com>
   8  *
   9  * SPDX-License-Identifier: LGPL-2.1-only
  10  *
  11  */
  12
  13
  14 typedef void (*lttng_release_func)(void *);
  15
  16 struct lttng_ref {
  17         unsigned long count;
  18         lttng_release_func release;
  19 };
  20
  21 static inline
  22 void lttng_ref_init(struct lttng_ref *ref, lttng_release_func release)
  23 {
  24         LTTNG_ASSERT(ref);
  25         ref->count = 1;
  26         ref->release = release;
  27 }
  28
  29 static inline
  30 void lttng_ref_get(struct lttng_ref *ref)
  31 {
  32         LTTNG_ASSERT(ref);
  33         ref->count++;
  34         /* Overflow check. */
  35         LTTNG_ASSERT(ref->count);
  36 }
  37
  38 static inline
  39 void lttng_ref_put(struct lttng_ref *ref)
  40 {
  41         LTTNG_ASSERT(ref);
  42         /* Underflow check. */
  43         LTTNG_ASSERT(ref->count);
  44         if (caa_unlikely((--ref->count) == 0)) {
  45                 ref->release(ref);
  46         }
  47 }
  48
  49 #endif /* LTTNG_REF_INTERNAL_H */