xref: /original-bsd/sys/sys/socketvar.h (revision c5b45afc)
1 /*
2  * Copyright (c) 1982 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  *
6  *	@(#)socketvar.h	6.10 (Berkeley) 02/17/86
7  */
8 
9 /*
10  * Kernel structure per socket.
11  * Contains send and receive buffer queues,
12  * handle on protocol and pointer to protocol
13  * private data and error information.
14  */
15 struct socket {
16 	short	so_type;		/* generic type, see socket.h */
17 	short	so_options;		/* from socket call, see socket.h */
18 	short	so_linger;		/* time to linger while closing */
19 	short	so_state;		/* internal state flags SS_*, below */
20 	caddr_t	so_pcb;			/* protocol control block */
21 	struct	protosw *so_proto;	/* protocol handle */
22 /*
23  * Variables for connection queueing.
24  * Socket where accepts occur is so_head in all subsidiary sockets.
25  * If so_head is 0, socket is not related to an accept.
26  * For head socket so_q0 queues partially completed connections,
27  * while so_q is a queue of connections ready to be accepted.
28  * If a connection is aborted and it has so_head set, then
29  * it has to be pulled out of either so_q0 or so_q.
30  * We allow connections to queue up based on current queue lengths
31  * and limit on number of queued connections for this socket.
32  */
33 	struct	socket *so_head;	/* back pointer to accept socket */
34 	struct	socket *so_q0;		/* queue of partial connections */
35 	short	so_q0len;		/* partials on so_q0 */
36 	struct	socket *so_q;		/* queue of incoming connections */
37 	short	so_qlen;		/* number of connections on so_q */
38 	short	so_qlimit;		/* max number queued connections */
39 /*
40  * Variables for socket buffering.
41  */
42 	struct	sockbuf {
43 		u_short	sb_cc;		/* actual chars in buffer */
44 		u_short	sb_hiwat;	/* max actual char count */
45 		u_short	sb_mbcnt;	/* chars of mbufs used */
46 		u_short	sb_mbmax;	/* max chars of mbufs to use */
47 		u_short	sb_lowat;	/* low water mark (not used yet) */
48 		short	sb_timeo;	/* timeout (not used yet) */
49 		struct	mbuf *sb_mb;	/* the mbuf chain */
50 		struct	proc *sb_sel;	/* process selecting read/write */
51 		short	sb_flags;	/* flags, see below */
52 	} so_rcv, so_snd;
53 #define	SB_MAX		65535		/* max chars in sockbuf */
54 #define	SB_LOCK		0x01		/* lock on data queue (so_rcv only) */
55 #define	SB_WANT		0x02		/* someone is waiting to lock */
56 #define	SB_WAIT		0x04		/* someone is waiting for data/space */
57 #define	SB_SEL		0x08		/* buffer is selected */
58 #define	SB_COLL		0x10		/* collision selecting */
59 	short	so_timeo;		/* connection timeout */
60 	u_short	so_error;		/* error affecting connection */
61 	u_short	so_oobmark;		/* chars to oob mark */
62 	short	so_pgrp;		/* pgrp for signals */
63 };
64 
65 /*
66  * Socket state bits.
67  */
68 #define	SS_NOFDREF		0x001	/* no file table ref any more */
69 #define	SS_ISCONNECTED		0x002	/* socket connected to a peer */
70 #define	SS_ISCONNECTING		0x004	/* in process of connecting to peer */
71 #define	SS_ISDISCONNECTING	0x008	/* in process of disconnecting */
72 #define	SS_CANTSENDMORE		0x010	/* can't send more data to peer */
73 #define	SS_CANTRCVMORE		0x020	/* can't receive more data from peer */
74 #define	SS_RCVATMARK		0x040	/* at mark on input */
75 
76 #define	SS_PRIV			0x080	/* privileged for broadcast, raw... */
77 #define	SS_NBIO			0x100	/* non-blocking ops */
78 #define	SS_ASYNC		0x200	/* async i/o notify */
79 
80 
81 /*
82  * Macros for sockets and socket buffering.
83  */
84 
85 /* how much space is there in a socket buffer (so->so_snd or so->so_rcv) */
86 #define	sbspace(sb) \
87     (MIN((int)((sb)->sb_hiwat - (sb)->sb_cc),\
88 	 (int)((sb)->sb_mbmax - (sb)->sb_mbcnt)))
89 
90 /* do we have to send all at once on a socket? */
91 #define	sosendallatonce(so) \
92     ((so)->so_proto->pr_flags & PR_ATOMIC)
93 
94 /* can we read something from so? */
95 #define	soreadable(so) \
96     ((so)->so_rcv.sb_cc || ((so)->so_state & SS_CANTRCVMORE) || \
97 	(so)->so_qlen || (so)->so_error)
98 
99 /* can we write something to so? */
100 #define	sowriteable(so) \
101     (sbspace(&(so)->so_snd) > 0 && \
102 	(((so)->so_state&SS_ISCONNECTED) || \
103 	  ((so)->so_proto->pr_flags&PR_CONNREQUIRED)==0) || \
104      ((so)->so_state & SS_CANTSENDMORE) || \
105      (so)->so_error)
106 
107 /* adjust counters in sb reflecting allocation of m */
108 #define	sballoc(sb, m) { \
109 	(sb)->sb_cc += (m)->m_len; \
110 	(sb)->sb_mbcnt += MSIZE; \
111 	if ((m)->m_off > MMAXOFF) \
112 		(sb)->sb_mbcnt += CLBYTES; \
113 }
114 
115 /* adjust counters in sb reflecting freeing of m */
116 #define	sbfree(sb, m) { \
117 	(sb)->sb_cc -= (m)->m_len; \
118 	(sb)->sb_mbcnt -= MSIZE; \
119 	if ((m)->m_off > MMAXOFF) \
120 		(sb)->sb_mbcnt -= CLBYTES; \
121 }
122 
123 /* set lock on sockbuf sb */
124 #define sblock(sb) { \
125 	while ((sb)->sb_flags & SB_LOCK) { \
126 		(sb)->sb_flags |= SB_WANT; \
127 		sleep((caddr_t)&(sb)->sb_flags, PZERO+1); \
128 	} \
129 	(sb)->sb_flags |= SB_LOCK; \
130 }
131 
132 /* release lock on sockbuf sb */
133 #define	sbunlock(sb) { \
134 	(sb)->sb_flags &= ~SB_LOCK; \
135 	if ((sb)->sb_flags & SB_WANT) { \
136 		(sb)->sb_flags &= ~SB_WANT; \
137 		wakeup((caddr_t)&(sb)->sb_flags); \
138 	} \
139 }
140 
141 #define	sorwakeup(so)	sowakeup((so), &(so)->so_rcv)
142 #define	sowwakeup(so)	sowakeup((so), &(so)->so_snd)
143 
144 #ifdef KERNEL
145 struct	socket *sonewconn();
146 struct	mbuf *sbdrop();
147 struct	mbuf *sbdroprecord();
148 #endif
149