xref: /original-bsd/sys/sys/socketvar.h (revision 1a56dd2c)
1 /*
2  * Copyright (c) 1982, 1986 Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are permitted
6  * provided that this notice is preserved and that due credit is given
7  * to the University of California at Berkeley. The name of the University
8  * may not be used to endorse or promote products derived from this
9  * software without specific prior written permission. This software
10  * is provided ``as is'' without express or implied warranty.
11  *
12  *	@(#)socketvar.h	7.3 (Berkeley) 12/30/87
13  */
14 
15 /*
16  * Kernel structure per socket.
17  * Contains send and receive buffer queues,
18  * handle on protocol and pointer to protocol
19  * private data and error information.
20  */
21 struct socket {
22 	short	so_type;		/* generic type, see socket.h */
23 	short	so_options;		/* from socket call, see socket.h */
24 	short	so_linger;		/* time to linger while closing */
25 	short	so_state;		/* internal state flags SS_*, below */
26 	caddr_t	so_pcb;			/* protocol control block */
27 	struct	protosw *so_proto;	/* protocol handle */
28 /*
29  * Variables for connection queueing.
30  * Socket where accepts occur is so_head in all subsidiary sockets.
31  * If so_head is 0, socket is not related to an accept.
32  * For head socket so_q0 queues partially completed connections,
33  * while so_q is a queue of connections ready to be accepted.
34  * If a connection is aborted and it has so_head set, then
35  * it has to be pulled out of either so_q0 or so_q.
36  * We allow connections to queue up based on current queue lengths
37  * and limit on number of queued connections for this socket.
38  */
39 	struct	socket *so_head;	/* back pointer to accept socket */
40 	struct	socket *so_q0;		/* queue of partial connections */
41 	struct	socket *so_q;		/* queue of incoming connections */
42 	short	so_q0len;		/* partials on so_q0 */
43 	short	so_qlen;		/* number of connections on so_q */
44 	short	so_qlimit;		/* max number queued connections */
45 	short	so_timeo;		/* connection timeout */
46 	u_short	so_error;		/* error affecting connection */
47 	short	so_pgrp;		/* pgrp for signals */
48 	u_long	so_oobmark;		/* chars to oob mark */
49 /*
50  * Variables for socket buffering.
51  */
52 	struct	sockbuf {
53 		u_long	sb_cc;		/* actual chars in buffer */
54 		u_long	sb_hiwat;	/* max actual char count */
55 		u_long	sb_mbcnt;	/* chars of mbufs used */
56 		u_long	sb_mbmax;	/* max chars of mbufs to use */
57 		u_long	sb_lowat;	/* low water mark (not used yet) */
58 		struct	mbuf *sb_mb;	/* the mbuf chain */
59 		struct	proc *sb_sel;	/* process selecting read/write */
60 		short	sb_timeo;	/* timeout (not used yet) */
61 		short	sb_flags;	/* flags, see below */
62 	} so_rcv, so_snd;
63 #define	SB_MAX		(64*1024)	/* max chars in sockbuf */
64 #define	SB_LOCK		0x01		/* lock on data queue (so_rcv only) */
65 #define	SB_WANT		0x02		/* someone is waiting to lock */
66 #define	SB_WAIT		0x04		/* someone is waiting for data/space */
67 #define	SB_SEL		0x08		/* buffer is selected */
68 #define	SB_COLL		0x10		/* collision selecting */
69 };
70 
71 /*
72  * Socket state bits.
73  */
74 #define	SS_NOFDREF		0x001	/* no file table ref any more */
75 #define	SS_ISCONNECTED		0x002	/* socket connected to a peer */
76 #define	SS_ISCONNECTING		0x004	/* in process of connecting to peer */
77 #define	SS_ISDISCONNECTING	0x008	/* in process of disconnecting */
78 #define	SS_CANTSENDMORE		0x010	/* can't send more data to peer */
79 #define	SS_CANTRCVMORE		0x020	/* can't receive more data from peer */
80 #define	SS_RCVATMARK		0x040	/* at mark on input */
81 
82 #define	SS_PRIV			0x080	/* privileged for broadcast, raw... */
83 #define	SS_NBIO			0x100	/* non-blocking ops */
84 #define	SS_ASYNC		0x200	/* async i/o notify */
85 
86 
87 /*
88  * Macros for sockets and socket buffering.
89  */
90 
91 /* how much space is there in a socket buffer (so->so_snd or so->so_rcv) */
92 #define	sbspace(sb) \
93     (MIN((long)((sb)->sb_hiwat - (sb)->sb_cc),\
94 	 (long)((sb)->sb_mbmax - (sb)->sb_mbcnt)))
95 
96 /* do we have to send all at once on a socket? */
97 #define	sosendallatonce(so) \
98     ((so)->so_proto->pr_flags & PR_ATOMIC)
99 
100 /* can we read something from so? */
101 #define	soreadable(so) \
102     ((so)->so_rcv.sb_cc || ((so)->so_state & SS_CANTRCVMORE) || \
103 	(so)->so_qlen || (so)->so_error)
104 
105 /* can we write something to so? */
106 #define	sowriteable(so) \
107     (sbspace(&(so)->so_snd) > 0 && \
108 	(((so)->so_state&SS_ISCONNECTED) || \
109 	  ((so)->so_proto->pr_flags&PR_CONNREQUIRED)==0) || \
110      ((so)->so_state & SS_CANTSENDMORE) || \
111      (so)->so_error)
112 
113 /* adjust counters in sb reflecting allocation of m */
114 #define	sballoc(sb, m) { \
115 	(sb)->sb_cc += (m)->m_len; \
116 	(sb)->sb_mbcnt += MSIZE; \
117 	if ((m)->m_off > MMAXOFF) \
118 		(sb)->sb_mbcnt += CLBYTES; \
119 }
120 
121 /* adjust counters in sb reflecting freeing of m */
122 #define	sbfree(sb, m) { \
123 	(sb)->sb_cc -= (m)->m_len; \
124 	(sb)->sb_mbcnt -= MSIZE; \
125 	if ((m)->m_off > MMAXOFF) \
126 		(sb)->sb_mbcnt -= CLBYTES; \
127 }
128 
129 /* set lock on sockbuf sb */
130 #define sblock(sb) { \
131 	while ((sb)->sb_flags & SB_LOCK) { \
132 		(sb)->sb_flags |= SB_WANT; \
133 		sleep((caddr_t)&(sb)->sb_flags, PZERO+1); \
134 	} \
135 	(sb)->sb_flags |= SB_LOCK; \
136 }
137 
138 /* release lock on sockbuf sb */
139 #define	sbunlock(sb) { \
140 	(sb)->sb_flags &= ~SB_LOCK; \
141 	if ((sb)->sb_flags & SB_WANT) { \
142 		(sb)->sb_flags &= ~SB_WANT; \
143 		wakeup((caddr_t)&(sb)->sb_flags); \
144 	} \
145 }
146 
147 #define	sorwakeup(so)	sowakeup((so), &(so)->so_rcv)
148 #define	sowwakeup(so)	sowakeup((so), &(so)->so_snd)
149 
150 #ifdef KERNEL
151 struct	socket *sonewconn();
152 #endif
153