[mirror_frr.git] / lib / fifo.h

/* FIFO common header.
   Copyright (C) 2015 Kunihiro Ishiguro

This file is part of Quagga.

Quagga 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 2, or (at your option) any
later version.

Quagga 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 GNU Zebra; see the file COPYING.  If not, write to the Free
Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
02111-1307, USA.  */
#ifndef __LIB_FIFO_H__
#define __LIB_FIFO_H__

/* FIFO -- first in first out structure and macros.  */
struct fifo {
	struct fifo *next;
	struct fifo *prev;
};

#define FIFO_INIT(F)                                                           \
	do {                                                                   \
		struct fifo *Xfifo = (struct fifo *)(F);                       \
		Xfifo->next = Xfifo->prev = Xfifo;                             \
	} while (0)

#define FIFO_ADD(F, N)                                                         \
	do {                                                                   \
		struct fifo *Xfifo = (struct fifo *)(F);                       \
		struct fifo *Xnode = (struct fifo *)(N);                       \
		Xnode->next = Xfifo;                                           \
		Xnode->prev = Xfifo->prev;                                     \
		Xfifo->prev = Xfifo->prev->next = Xnode;                       \
	} while (0)

#define FIFO_DEL(N)                                                            \
	do {                                                                   \
		struct fifo *Xnode = (struct fifo *)(N);                       \
		Xnode->prev->next = Xnode->next;                               \
		Xnode->next->prev = Xnode->prev;                               \
	} while (0)

#define FIFO_HEAD(F)                                                           \
	((((struct fifo *)(F))->next == (struct fifo *)(F)) ? NULL : (F)->next)

#define FIFO_EMPTY(F) (((struct fifo *)(F))->next == (struct fifo *)(F))

#define FIFO_TOP(F) (FIFO_EMPTY(F) ? NULL : ((struct fifo *)(F))->next)

#endif /* __LIB_FIFO_H__ */
Commit	Line	Data
ea863ec6 DS	1	/* FIFO common header.
	2	Copyright (C) 2015 Kunihiro Ishiguro
	3
	4	This file is part of Quagga.
	5
	6	Quagga is free software; you can redistribute it and/or modify it
	7	under the terms of the GNU General Public License as published by the
	8	Free Software Foundation; either version 2, or (at your option) any
	9	later version.
	10
	11	Quagga is distributed in the hope that it will be useful, but
	12	WITHOUT ANY WARRANTY; without even the implied warranty of
	13	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	14	General Public License for more details.
	15
	16	You should have received a copy of the GNU General Public License
	17	along with GNU Zebra; see the file COPYING. If not, write to the Free
	18	Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
	19	02111-1307, USA. */
	20	#ifndef __LIB_FIFO_H__
	21	#define __LIB_FIFO_H__
	22
	23	/* FIFO -- first in first out structure and macros. */
ac4d0be5	24	struct fifo {
	25	struct fifo *next;
	26	struct fifo *prev;
ea863ec6 DS	27	};
ea863ec6 DS	28
ac4d0be5	29	#define FIFO_INIT(F) \
	30	do { \
	31	struct fifo Xfifo = (struct fifo )(F); \
	32	Xfifo->next = Xfifo->prev = Xfifo; \
	33	} while (0)
	34
	35	#define FIFO_ADD(F, N) \
	36	do { \
	37	struct fifo Xfifo = (struct fifo )(F); \
	38	struct fifo Xnode = (struct fifo )(N); \
	39	Xnode->next = Xfifo; \
	40	Xnode->prev = Xfifo->prev; \
	41	Xfifo->prev = Xfifo->prev->next = Xnode; \
	42	} while (0)
	43
	44	#define FIFO_DEL(N) \
	45	do { \
	46	struct fifo Xnode = (struct fifo )(N); \
	47	Xnode->prev->next = Xnode->next; \
	48	Xnode->next->prev = Xnode->prev; \
	49	} while (0)
	50
	51	#define FIFO_HEAD(F) \
	52	((((struct fifo )(F))->next == (struct fifo )(F)) ? NULL : (F)->next)
	53
	54	#define FIFO_EMPTY(F) (((struct fifo )(F))->next == (struct fifo )(F))
	55
	56	#define FIFO_TOP(F) (FIFO_EMPTY(F) ? NULL : ((struct fifo *)(F))->next)
ea863ec6 DS	57
ea863ec6 DS	58	#endif /* __LIB_FIFO_H__ */