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+/*
+ SSSD
+
+ Simple reference counting wrappers for talloc.
+
+ Authors:
+ Martin Nagy <mnagy@redhat.com>
+
+ Copyright (C) Red Hat, Inc 2009
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef __REFCOUNT_H__
+#define __REFCOUNT_H__
+
+#include <stddef.h>
+
+#define REFCOUNT_MEMBER_NAME DO_NOT_TOUCH_THIS_MEMBER_refcount
+
+/*
+ * Include this member in your structure in order to be able to use it with
+ * the refcount_* functions.
+ */
+#define REFCOUNT_COMMON int REFCOUNT_MEMBER_NAME
+
+/*
+ * Allocate a new structure that uses reference counting. The resulting pointer
+ * returned. You must not free the returned pointer manually. It will be freed
+ * when 'ctx' is freed with talloc_free() and no other references are left.
+ */
+#define rc_alloc(ctx, type) \
+ (type *)_rc_alloc(ctx, sizeof(type), offsetof(type, REFCOUNT_MEMBER_NAME), \
+ #type)
+
+/*
+ * Increment the reference count of 'src' and return it back if we are
+ * successful. The reference count will be decremented after 'ctx' has been
+ * released by talloc_free(). The function will return NULL in case of failure.
+ */
+#define rc_reference(ctx, type, src) \
+ (type *)_rc_reference(ctx, offsetof(type, REFCOUNT_MEMBER_NAME), src)
+
+/*
+ * These functions should not be used directly. Use the above macros instead.
+ */
+void *_rc_alloc(const void *context, size_t size, size_t refcount_offset,
+ const char *type_name);
+void *_rc_reference(const void *context, size_t refcount_offset, void *source);
+
+
+#endif /* !__REFCOUNT_H__ */