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Diffstat (limited to 'slirp/mbuf.h')
| -rw-r--r-- | slirp/mbuf.h | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/slirp/mbuf.h b/slirp/mbuf.h new file mode 100644 index 0000000000..8cc292bbfb --- /dev/null +++ b/slirp/mbuf.h @@ -0,0 +1,147 @@ +/* + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 4. 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)); +void msize_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 |