Separate session info from channel info in notification thread

[lttng-tools.git] / include / lttng / ref-internal.h

diff --git a/include/lttng/ref-internal.h b/include/lttng/ref-internal.h
new file mode 100644 (file)
index 0000000..4ecb2e2
--- /dev/null
+++ b/include/lttng/ref-internal.h
@@ -0,0 +1,62 @@
+#ifndef LTTNG_REF_INTERNAL_H
+#define LTTNG_REF_INTERNAL_H
+
+/*
+ * LTTng - Non thread-safe reference counting
+ *
+ * Copyright 2013, 2014 Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * Author: Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ *
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License, version 2.1 only,
+ * as published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <assert.h>
+
+typedef void (*lttng_release_func)(void *);
+
+struct lttng_ref {
+       unsigned long count;
+       lttng_release_func release;
+};
+
+static inline
+void lttng_ref_init(struct lttng_ref *ref, lttng_release_func release)
+{
+       assert(ref);
+       ref->count = 1;
+       ref->release = release;
+}
+
+static inline
+void lttng_ref_get(struct lttng_ref *ref)
+{
+       assert(ref);
+       ref->count++;
+       /* Overflow check. */
+       assert(ref->count);
+}
+
+static inline
+void lttng_ref_put(struct lttng_ref *ref)
+{
+       assert(ref);
+       /* Underflow check. */
+       assert(ref->count);
+       if (caa_unlikely((--ref->count) == 0)) {
+               ref->release(ref);
+       }
+}
+
+#endif /* LTTNG_REF_INTERNAL_H */