wrapper/list.h

   1 #ifndef _LTTNG_WRAPPER_LIST_H
   2 #define _LTTNG_WRAPPER_LIST_H
   3
   4 /*
   5  * wrapper/list.h
   6  *
   7  * wrapper around linux/list.h.
   8  *
   9  * Copyright (C) 2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
  10  *
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; only version 2 of the License.
  14  *
  15  * This program is distributed in the hope that it will be useful,
  16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18  * GNU General Public License for more details.
  19  *
  20  * You should have received a copy of the GNU General Public License along
  21  * with this program; if not, write to the Free Software Foundation, Inc.,
  22  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  23  *
  24  * This wrapper code is derived from Linux 3.19.2 include/linux/list.h
  25  * and include/linux/rculist.h, hence the GPLv2 license applied to this
  26  * file.
  27  */
  28
  29 #include <linux/list.h>
  30 #include <linux/rculist.h>
  31
  32 /*
  33  * return the first or the next element in an RCU protected hlist
  34  */
  35 #define lttng_hlist_first_rcu(head)     (*((struct hlist_node __rcu **)(&(head)->first)))
  36 #define lttng_hlist_next_rcu(node)      (*((struct hlist_node __rcu **)(&(node)->next)))
  37 #define lttng_hlist_pprev_rcu(node)     (*((struct hlist_node __rcu **)((node)->pprev)))
  38
  39 #define lttng_hlist_entry_safe(ptr, type, member) \
  40         ({ typeof(ptr) ____ptr = (ptr); \
  41            ____ptr ? hlist_entry(____ptr, type, member) : NULL; \
  42         })
  43
  44 /**
  45  * lttng_hlist_for_each_entry   - iterate over list of given type
  46  * @pos:        the type * to use as a loop cursor.
  47  * @head:       the head for your list.
  48  * @member:     the name of the hlist_node within the struct.
  49  */
  50 #define lttng_hlist_for_each_entry(pos, head, member)                   \
  51         for (pos = lttng_hlist_entry_safe((head)->first, typeof(*(pos)), member);\
  52              pos;                                                       \
  53              pos = lttng_hlist_entry_safe((pos)->member.next, typeof(*(pos)), member))
  54
  55 /**
  56  * lttng_hlist_for_each_entry_safe - iterate over list of given type safe against removal of list entry
  57  * @pos:        the type * to use as a loop cursor.
  58  * @n:          another &struct hlist_node to use as temporary storage
  59  * @head:       the head for your list.
  60  * @member:     the name of the hlist_node within the struct.
  61  */
  62 #define lttng_hlist_for_each_entry_safe(pos, n, head, member)           \
  63         for (pos = lttng_hlist_entry_safe((head)->first, typeof(*pos), member);\
  64              pos && ({ n = pos->member.next; 1; });                     \
  65              pos = lttng_hlist_entry_safe(n, typeof(*pos), member))
  66
  67 #endif /* _LTTNG_WRAPPER_LIST_H */