//==========================================================================
//
//      include/sys/socketvar.h
//
//==========================================================================
//####BSDCOPYRIGHTBEGIN####
//
// -------------------------------------------
//
// Portions of this software may have been derived from OpenBSD, 
// FreeBSD or other sources, and are covered by the appropriate
// copyright disclaimers included herein.
//
// Portions created by Red Hat are
// Copyright (C) 2002 Red Hat, Inc. All Rights Reserved.
//
// -------------------------------------------
//
//####BSDCOPYRIGHTEND####
//==========================================================================

/*-
 * Copyright (c) 1982, 1986, 1990, 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.
 *
 *	@(#)socketvar.h	8.3 (Berkeley) 2/19/95
 * $FreeBSD: src/sys/sys/socketvar.h,v 1.46.2.6 2001/08/31 13:45:49 jlemon Exp $
 */

#ifndef _SYS_SOCKETVAR_H_
#define _SYS_SOCKETVAR_H_

#include <sys/queue.h>			/* for TAILQ macros */

/*
 * Kernel structure per socket.
 * Contains send and receive buffer queues,
 * handle on protocol and pointer to protocol
 * private data and error information.
 */
typedef	u_quad_t so_gen_t;

struct accept_filter;

struct socket {
	struct	vm_zone *so_zone;	/* zone we were allocated from */
	short	so_type;		/* generic type, see socket.h */
	short	so_options;		/* from socket call, see socket.h */
	short	so_linger;		/* time to linger while closing */
	short	so_state;		/* internal state flags SS_*, below */
	caddr_t	so_pcb;			/* protocol control block */
	struct	protosw *so_proto;	/* protocol handle */
/*
 * Variables for connection queuing.
 * Socket where accepts occur is so_head in all subsidiary sockets.
 * If so_head is 0, socket is not related to an accept.
 * For head socket so_incomp queues partially completed connections,
 * while so_comp is a queue of connections ready to be accepted.
 * If a connection is aborted and it has so_head set, then
 * it has to be pulled out of either so_incomp or so_comp.
 * We allow connections to queue up based on current queue lengths
 * and limit on number of queued connections for this socket.
 */
	struct	socket *so_head;	/* back pointer to accept socket */
	TAILQ_HEAD(, socket) so_incomp;	/* queue of partial unaccepted connections */
	TAILQ_HEAD(, socket) so_comp;	/* queue of complete unaccepted connections */
	TAILQ_ENTRY(socket) so_list;	/* list of unaccepted connections */
	short	so_qlen;		/* number of unaccepted connections */
	short	so_incqlen;		/* number of unaccepted incomplete
					   connections */
	short	so_qlimit;		/* max number queued connections */
	short	so_timeo;		/* connection timeout */
	u_short	so_error;		/* error affecting connection */
	struct  sigio *so_sigio;	/* information for async I/O or
					   out of band data (SIGURG) */
	u_long	so_oobmark;		/* chars to oob mark */
	TAILQ_HEAD(, aiocblist) so_aiojobq; /* AIO ops waiting on socket */
/*
 * Variables for socket buffering.
 */
	struct	sockbuf {
		u_long	sb_cc;		/* actual chars in buffer */
		u_long	sb_hiwat;	/* max actual char count */
		u_long	sb_mbcnt;	/* chars of mbufs used */
		u_long	sb_mbmax;	/* max chars of mbufs to use */
		long	sb_lowat;	/* low water mark */
		struct	mbuf *sb_mb;	/* the mbuf chain */
		struct	selinfo sb_sel;	/* process selecting read/write */
		short	sb_flags;	/* flags, see below */
		short	sb_timeo;	/* timeout for read/write */
	} so_rcv, so_snd;
#define	SB_MAX		(256*1024)	/* default for max chars in sockbuf */
#define	SB_LOCK		0x01		/* lock on data queue */
#define	SB_WANT		0x02		/* someone is waiting to lock */
#define	SB_WAIT		0x04		/* someone is waiting for data/space */
#define	SB_SEL		0x08		/* someone is selecting */
#define	SB_ASYNC	0x10		/* ASYNC I/O, need signals */
#define	SB_UPCALL	0x20		/* someone wants an upcall */
#define	SB_NOINTR	0x40		/* operations not interruptible */
#define SB_AIO		0x80		/* AIO operations queued */
#define SB_KNOTE	0x100		/* kernel note attached */

	void	(*so_upcall) __P((struct socket *, void *, int));
	void	*so_upcallarg;
	struct	ucred *so_cred;		/* user credentials */
	/* NB: generation count must not be first; easiest to make it last. */
	so_gen_t so_gencnt;		/* generation count */
	void	*so_emuldata;		/* private data for emulators */
	struct	so_accf { 
		struct	accept_filter *so_accept_filter;
		void	*so_accept_filter_arg;	/* saved filter args */
		char	*so_accept_filter_str;	/* saved user args */
	} *so_accf;
};

/*
 * Socket state bits.
 */
#define	SS_NOFDREF		0x0001	/* no file table ref any more */
#define	SS_ISCONNECTED		0x0002	/* socket connected to a peer */
#define	SS_ISCONNECTING		0x0004	/* in process of connecting to peer */
#define	SS_ISDISCONNECTING	0x0008	/* in process of disconnecting */
#define	SS_CANTSENDMORE		0x0010	/* can't send more data to peer */
#define	SS_CANTRCVMORE		0x0020	/* can't receive more data from peer */
#define	SS_RCVATMARK		0x0040	/* at mark on input */

#define	SS_NBIO			0x0100	/* non-blocking ops */
#define	SS_ASYNC		0x0200	/* async i/o notify */
#define	SS_ISCONFIRMING		0x0400	/* deciding to accept connection req */

#define	SS_INCOMP		0x0800	/* unaccepted, incomplete connection */
#define	SS_COMP			0x1000	/* unaccepted, complete connection */
#define	SS_ISDISCONNECTED	0x2000	/* socket disconnected from peer */

/*
 * Externalized form of struct socket used by the sysctl(3) interface.
 */
struct	xsocket {
	size_t	xso_len;	/* length of this structure */
	struct	socket *xso_so;	/* makes a convenient handle sometimes */
	short	so_type;
	short	so_options;
	short	so_linger;
	short	so_state;
	caddr_t	so_pcb;		/* another convenient handle */
	int	xso_protocol;
	int	xso_family;
	short	so_qlen;
	short	so_incqlen;
	short	so_qlimit;
	short	so_timeo;
	u_short	so_error;
	pid_t	so_pgid;
	u_long	so_oobmark;
	struct	xsockbuf {
		u_long	sb_cc;
		u_long	sb_hiwat;
		u_long	sb_mbcnt;
		u_long	sb_mbmax;
		long	sb_lowat;
		short	sb_flags;
		short	sb_timeo;
	} so_rcv, so_snd;
	uid_t	so_uid;		/* XXX */
};

/*
 * Macros for sockets and socket buffering.
 */

/*
 * Do we need to notify the other side when I/O is possible?
 */
#define	sb_notify(sb)	(((sb)->sb_flags & (SB_WAIT | SB_SEL | SB_ASYNC | \
    SB_UPCALL | SB_AIO | SB_KNOTE)) != 0)

/*
 * How much space is there in a socket buffer (so->so_snd or so->so_rcv)?
 * This is problematical if the fields are unsigned, as the space might
 * still be negative (cc > hiwat or mbcnt > mbmax).  Should detect
 * overflow and return 0.  Should use "lmin" but it doesn't exist now.
 */
#define	sbspace(sb) \
    ((long) imin((int)((sb)->sb_hiwat - (sb)->sb_cc), \
	 (int)((sb)->sb_mbmax - (sb)->sb_mbcnt)))

/* do we have to send all at once on a socket? */
#define	sosendallatonce(so) \
    ((so)->so_proto->pr_flags & PR_ATOMIC)