1/*-
2 * Copyright (c) 1989, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Rick Macklem at The University of Guelph.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * $FreeBSD$
33 */
34
35#ifndef _NFS_NFSM_SUBS_H_
36#define	_NFS_NFSM_SUBS_H_
37
38
39/*
40 * These macros do strange and peculiar things to mbuf chains for
41 * the assistance of the nfs code. To attempt to use them for any
42 * other purpose will be dangerous. (they make weird assumptions)
43 */
44
45#ifndef APPLE
46/*
47 * First define what the actual subs. return
48 */
49#define	M_HASCL(m)	((m)->m_flags & M_EXT)
50#define	NFSMINOFF(m) 							\
51		if (M_HASCL(m)) 					\
52			(m)->m_data = (m)->m_ext.ext_buf; 		\
53		else if ((m)->m_flags & M_PKTHDR) 			\
54			(m)->m_data = (m)->m_pktdat; 			\
55				else 					\
56			(m)->m_data = (m)->m_dat
57#define	NFSMSIZ(m)	((M_HASCL(m))?MCLBYTES: 			\
58				(((m)->m_flags & M_PKTHDR)?MHLEN:MLEN))
59#define	NFSM_DATAP(m, s)	(m)->m_data += (s)
60
61/*
62 * Now for the macros that do the simple stuff and call the functions
63 * for the hard stuff.
64 * They use fields in struct nfsrv_descript to handle the mbuf queues.
65 * Replace most of the macro with an inline function, to minimize
66 * the machine code. The inline functions in lower case can be called
67 * directly, bypassing the macro.
68 */
69static __inline void *
70nfsm_build(struct nfsrv_descript *nd, int siz)
71{
72	void *retp;
73	struct mbuf *mb2;
74
75	if (siz > M_TRAILINGSPACE(nd->nd_mb)) {
76		NFSMCLGET(mb2, M_DONTWAIT);
77		if (siz > MLEN)
78			panic("build > MLEN");
79		mbuf_setlen(mb2, 0);
80		nd->nd_bpos = NFSMTOD(mb2, caddr_t);
81		nd->nd_mb->m_next = mb2;
82		nd->nd_mb = mb2;
83	}
84	retp = (void *)(nd->nd_bpos);
85	nd->nd_mb->m_len += siz;
86	nd->nd_bpos += siz;
87	return (retp);
88}
89
90#define	NFSM_BUILD(a, c, s)	((a) = (c)nfsm_build(nd, (s)))
91
92static __inline void *
93nfsm_dissect(struct nfsrv_descript *nd, int siz)
94{
95	int tt1;
96	void *retp;
97
98	tt1 = NFSMTOD(nd->nd_md, caddr_t) + nd->nd_md->m_len - nd->nd_dpos;
99	if (tt1 >= siz) {
100		retp = (void *)nd->nd_dpos;
101		nd->nd_dpos += siz;
102	} else {
103		retp = nfsm_dissct(nd, siz, M_WAITOK);
104	}
105	return (retp);
106}
107
108static __inline void *
109nfsm_dissect_nonblock(struct nfsrv_descript *nd, int siz)
110{
111	int tt1;
112	void *retp;
113
114	tt1 = NFSMTOD(nd->nd_md, caddr_t) + nd->nd_md->m_len - nd->nd_dpos;
115	if (tt1 >= siz) {
116		retp = (void *)nd->nd_dpos;
117		nd->nd_dpos += siz;
118	} else {
119		retp = nfsm_dissct(nd, siz, M_NOWAIT);
120	}
121	return (retp);
122}
123
124#define	NFSM_DISSECT(a, c, s) 						\
125	do {								\
126		(a) = (c)nfsm_dissect(nd, (s));	 			\
127		if ((a) == NULL) { 					\
128			error = EBADRPC; 				\
129			goto nfsmout; 					\
130		}							\
131	} while (0)
132
133#define	NFSM_DISSECT_NONBLOCK(a, c, s) 					\
134	do {								\
135		(a) = (c)nfsm_dissect_nonblock(nd, (s));		\
136		if ((a) == NULL) { 					\
137			error = EBADRPC; 				\
138			goto nfsmout; 					\
139		}							\
140	} while (0)
141#endif	/* !APPLE */
142
143#define	NFSM_STRSIZ(s, m)  						\
144	do {								\
145		tl = (u_int32_t *)nfsm_dissect(nd, NFSX_UNSIGNED);	\
146		if (!tl || ((s) = fxdr_unsigned(int32_t, *tl)) > (m)) { \
147			error = EBADRPC; 				\
148			goto nfsmout; 					\
149		}							\
150	} while (0)
151
152#define	NFSM_RNDUP(a)	(((a)+3)&(~0x3))
153
154#endif	/* _NFS_NFSM_SUBS_H_ */
155