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Diffstat (limited to 'slirp2/mbuf.h')
-rw-r--r-- | slirp2/mbuf.h | 121 |
1 files changed, 121 insertions, 0 deletions
diff --git a/slirp2/mbuf.h b/slirp2/mbuf.h new file mode 100644 index 0000000..ed83372 --- /dev/null +++ b/slirp2/mbuf.h @@ -0,0 +1,121 @@ +/* + * 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 MINCSIZE 4096 /* Amount to increase mbuf if too small */ + +/* flags for the mh_flags field */ +#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 mbuf_free is called on the mbuf, free() + * it rather than putting it on the free list */ + + +/* 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, mbuf_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: */ + +/** + * m_next, m_prev :: used to place the MBuf in free/used linked lists + * m_next2, m_prev2 :: used to place the same MBuf in other linked lists + * m_flags :: bit flags describing this MBuf + * m_size :: total size of MBuf buffer + * m_so :: socket this MBuf is attached to + * m_data :: pointer to current cursor in MBuf buffer + * m_len :: amount of data recorded in this MBuf + */ +#define MBUF_HEADER \ + struct mbuf* m_next; \ + struct mbuf* m_prev; \ + struct mbuf* m_next2; \ + struct mbuf* m_prev2; \ + int m_flags; \ + int m_size; \ + struct socket* m_so; \ + caddr_t m_data; \ + int m_len; + +struct m_hdr { + MBUF_HEADER +}; + +typedef struct mbuf { + MBUF_HEADER + union M_dat { + char m_dat_[1]; /* ANSI doesn't like 0 sized arrays */ + char* m_ext_; + } M_dat; +} MBufRec, *MBuf; + +#define m_nextpkt m_next2 +#define m_prevpkt m_prev2 +#define m_dat M_dat.m_dat_ +#define m_ext M_dat.m_ext_ + +#define ifq_prev m_prev +#define ifq_next m_next + +#define ifs_prev m_prev2 +#define ifs_next m_next2 + +#define ifq_so m_so + +void mbuf_init (void); +void msize_init (void); +MBuf mbuf_alloc (void); +void mbuf_free (MBuf m); +void mbuf_append(MBuf m1, MBuf m2); +void mbuf_ensure(MBuf m, int size); +void mbuf_trim (MBuf m, int len); +int mbuf_copy (MBuf m, MBuf n, int n_offset, int n_length); + +#define MBUF_TO(m,t) ((t)(m)->m_data) +#define MBUF_FROM(d) mbuf_from(d) +MBuf mbuf_from (void *); + +int mbuf_freeroom( MBuf m ); + +#endif |