[qemu.git] / slirp / mbuf.h

/*
 * Copyright (c) 1982, 1986, 1988, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)mbuf.h	8.3 (Berkeley) 1/21/94
 * mbuf.h,v 1.9 1994/11/14 13:54:20 bde Exp
 */

#ifndef _MBUF_H_
#define _MBUF_H_

#define m_freem m_free


#define MINCSIZE 4096	/* Amount to increase mbuf if too small */

/*
 * Macros for type conversion
 * mtod(m,t) -	convert mbuf pointer to data pointer of correct type
 * dtom(x) -	convert data pointer within mbuf to mbuf pointer (XXX)
 */
#define mtod(m,t)	((t)(m)->m_data)
/* #define	dtom(x)		((struct mbuf *)((int)(x) & ~(M_SIZE-1))) */

/* XXX About mbufs for slirp:
 * Only one mbuf is ever used in a chain, for each "cell" of data.
 * m_nextpkt points to the next packet, if fragmented.
 * If the data is too large, the M_EXT is used, and a larger block
 * is alloced.  Therefore, m_free[m] must check for M_EXT and if set
 * free the m_ext.  This is inefficient memory-wise, but who cares.
 */

/* XXX should union some of these! */
/* header at beginning of each mbuf: */
struct m_hdr {
	struct	mbuf *mh_next;		/* Linked list of mbufs */
	struct	mbuf *mh_prev;
	struct	mbuf *mh_nextpkt;	/* Next packet in queue/record */
	struct	mbuf *mh_prevpkt; /* Flags aren't used in the output queue */
	int	mh_flags;	  /* Misc flags */

	int	mh_size;		/* Size of data */
	struct	socket *mh_so;

	caddr_t	mh_data;		/* Location of data */
	int	mh_len;			/* Amount of data in this mbuf */
};

/*
 * How much room is in the mbuf, from m_data to the end of the mbuf
 */
#define M_ROOM(m) ((m->m_flags & M_EXT)? \
			(((m)->m_ext + (m)->m_size) - (m)->m_data) \
		   : \
			(((m)->m_dat + (m)->m_size) - (m)->m_data))

/*
 * How much free room there is
 */
#define M_FREEROOM(m) (M_ROOM(m) - (m)->m_len)
#define M_TRAILINGSPACE M_FREEROOM

struct mbuf {
	struct	m_hdr m_hdr;
	union M_dat {
		char	m_dat_[1]; /* ANSI don't like 0 sized arrays */
		char	*m_ext_;
	} M_dat;
};

#define m_next		m_hdr.mh_next
#define m_prev		m_hdr.mh_prev
#define m_nextpkt	m_hdr.mh_nextpkt
#define m_prevpkt	m_hdr.mh_prevpkt
#define m_flags		m_hdr.mh_flags
#define	m_len		m_hdr.mh_len
#define	m_data		m_hdr.mh_data
#define m_size		m_hdr.mh_size
#define m_dat		M_dat.m_dat_
#define m_ext		M_dat.m_ext_
#define m_so		m_hdr.mh_so

#define ifq_prev m_prev
#define ifq_next m_next
#define ifs_prev m_prevpkt
#define ifs_next m_nextpkt
#define ifq_so m_so

#define M_EXT			0x01	/* m_ext points to more (malloced) data */
#define M_FREELIST		0x02	/* mbuf is on free list */
#define M_USEDLIST		0x04	/* XXX mbuf is on used list (for dtom()) */
#define M_DOFREE		0x08	/* when m_free is called on the mbuf, free()
					 * it rather than putting it on the free list */

/*
 * Mbuf statistics. XXX
 */

struct mbstat {
	int mbs_alloced;		/* Number of mbufs allocated */

};

extern struct	mbstat mbstat;
extern int mbuf_alloced;
extern struct mbuf m_freelist, m_usedlist;
extern int mbuf_max;

void m_init _P((void));
struct mbuf * m_get _P((void));
void m_free _P((struct mbuf *));
void m_cat _P((register struct mbuf *, register struct mbuf *));
void m_inc _P((struct mbuf *, int));
void m_adj _P((struct mbuf *, int));
int m_copy _P((struct mbuf *, struct mbuf *, int, int));
struct mbuf * dtom _P((void *));

#endif
Commit	Line	Data
f0cbd3ec FB	1	/*
	2	* Copyright (c) 1982, 1986, 1988, 1993
	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
2f5f8996	13	* 3. Neither the name of the University nor the names of its contributors
f0cbd3ec FB	14	* may be used to endorse or promote products derived from this software
	15	* without specific prior written permission.
	16	*
	17	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	18	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	19	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	20	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	21	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	22	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	23	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	24	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	25	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	26	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	27	* SUCH DAMAGE.
	28	*
	29	* @(#)mbuf.h 8.3 (Berkeley) 1/21/94
	30	* mbuf.h,v 1.9 1994/11/14 13:54:20 bde Exp
	31	*/
	32
	33	#ifndef _MBUF_H_
	34	#define _MBUF_H_
	35
	36	#define m_freem m_free
	37
	38
	39	#define MINCSIZE 4096 /* Amount to increase mbuf if too small */
	40
	41	/*
	42	* Macros for type conversion
	43	* mtod(m,t) - convert mbuf pointer to data pointer of correct type
	44	* dtom(x) - convert data pointer within mbuf to mbuf pointer (XXX)
	45	*/
	46	#define mtod(m,t) ((t)(m)->m_data)
	47	/* #define dtom(x) ((struct mbuf )((int)(x) & ~(M_SIZE-1))) /
	48
	49	/* XXX About mbufs for slirp:
	50	* Only one mbuf is ever used in a chain, for each "cell" of data.
	51	* m_nextpkt points to the next packet, if fragmented.
	52	* If the data is too large, the M_EXT is used, and a larger block
	53	* is alloced. Therefore, m_free[m] must check for M_EXT and if set
	54	* free the m_ext. This is inefficient memory-wise, but who cares.
	55	*/
	56
	57	/* XXX should union some of these! */
	58	/* header at beginning of each mbuf: */
	59	struct m_hdr {
	60	struct mbuf mh_next; / Linked list of mbufs */
	61	struct mbuf *mh_prev;
	62	struct mbuf mh_nextpkt; / Next packet in queue/record */
	63	struct mbuf mh_prevpkt; / Flags aren't used in the output queue */
	64	int mh_flags; /* Misc flags */
	65
	66	int mh_size; /* Size of data */
	67	struct socket *mh_so;
5fafdf24	68
f0cbd3ec FB	69	caddr_t mh_data; /* Location of data */
	70	int mh_len; /* Amount of data in this mbuf */
	71	};
	72
5fafdf24	73	/*
f0cbd3ec FB	74	* How much room is in the mbuf, from m_data to the end of the mbuf
	75	*/
	76	#define M_ROOM(m) ((m->m_flags & M_EXT)? \
	77	(((m)->m_ext + (m)->m_size) - (m)->m_data) \
	78	: \
	79	(((m)->m_dat + (m)->m_size) - (m)->m_data))
	80
	81	/*
	82	* How much free room there is
	83	*/
	84	#define M_FREEROOM(m) (M_ROOM(m) - (m)->m_len)
	85	#define M_TRAILINGSPACE M_FREEROOM
	86
	87	struct mbuf {
	88	struct m_hdr m_hdr;
	89	union M_dat {
	90	char m_dat_[1]; /* ANSI don't like 0 sized arrays */
	91	char *m_ext_;
	92	} M_dat;
	93	};
	94
	95	#define m_next m_hdr.mh_next
	96	#define m_prev m_hdr.mh_prev
	97	#define m_nextpkt m_hdr.mh_nextpkt
	98	#define m_prevpkt m_hdr.mh_prevpkt
	99	#define m_flags m_hdr.mh_flags
	100	#define m_len m_hdr.mh_len
	101	#define m_data m_hdr.mh_data
	102	#define m_size m_hdr.mh_size
	103	#define m_dat M_dat.m_dat_
	104	#define m_ext M_dat.m_ext_
	105	#define m_so m_hdr.mh_so
	106
	107	#define ifq_prev m_prev
	108	#define ifq_next m_next
	109	#define ifs_prev m_prevpkt
	110	#define ifs_next m_nextpkt
	111	#define ifq_so m_so
	112
	113	#define M_EXT 0x01 /* m_ext points to more (malloced) data */
	114	#define M_FREELIST 0x02 /* mbuf is on free list */
	115	#define M_USEDLIST 0x04 /* XXX mbuf is on used list (for dtom()) */
	116	#define M_DOFREE 0x08 /* when m_free is called on the mbuf, free()
	117	* it rather than putting it on the free list */
	118
	119	/*
	120	* Mbuf statistics. XXX
	121	*/
	122
	123	struct mbstat {
	124	int mbs_alloced; /* Number of mbufs allocated */
5fafdf24	125
f0cbd3ec FB	126	};
	127
	128	extern struct mbstat mbstat;
	129	extern int mbuf_alloced;
	130	extern struct mbuf m_freelist, m_usedlist;
	131	extern int mbuf_max;
	132
	133	void m_init _P((void));
f0cbd3ec FB	134	struct mbuf * m_get _P((void));
	135	void m_free _P((struct mbuf *));
	136	void m_cat _P((register struct mbuf , register struct mbuf ));
	137	void m_inc _P((struct mbuf *, int));
	138	void m_adj _P((struct mbuf *, int));
	139	int m_copy _P((struct mbuf , struct mbuf , int, int));
	140	struct mbuf * dtom _P((void *));
	141
	142	#endif