/* * Copyright (c) 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. * * @(#)ring.h 8.1 (Berkeley) 6/6/93 * $FreeBSD: src/crypto/telnet/telnet/ring.h,v 1.1.1.1.8.1 2002/04/13 10:59:08 markm Exp $ */ #if defined(P) # undef P #endif #if defined(__STDC__) || defined(LINT_ARGS) # define P(x) x #else # define P(x) () #endif /* * This defines a structure for a ring buffer. * * The circular buffer has two parts: *((( * full: [consume, supply) * empty: [supply, consume) *]]] * */ typedef struct { unsigned char *consume, /* where data comes out of */ *supply, /* where data comes in to */ *bottom, /* lowest address in buffer */ *top, /* highest address+1 in buffer */ *mark; /* marker (user defined) */ #ifdef ENCRYPTION unsigned char *clearto; /* Data to this point is clear text */ unsigned char *encryyptedto; /* Data is encrypted to here */ #endif /* ENCRYPTION */ int size; /* size in bytes of buffer */ u_long consumetime, /* help us keep straight full, empty, etc. */ supplytime; } Ring; /* Here are some functions and macros to deal with the ring buffer */ /* Initialization routine */ extern int ring_init(Ring *ring, unsigned char *buffer, int count); /* Data movement routines */ extern void ring_supply_data(Ring *ring, unsigned char *buffer, int count); #ifdef notdef extern void ring_consume_data(Ring *ring, unsigned char *buffer, int count); #endif /* Buffer state transition routines */ extern void ring_supplied(Ring *ring, int count), ring_consumed(Ring *ring, int count); /* Buffer state query routines */ extern int ring_at_mark(Ring *), ring_empty_count(Ring *ring), ring_empty_consecutive(Ring *ring), ring_full_count(Ring *ring), ring_full_consecutive(Ring *ring); #ifdef ENCRYPTION extern void ring_encrypt(Ring *ring, void (*func)(unsigned char *, int)), ring_clearto(Ring *ring); #endif /* ENCRYPTION */ extern void ring_clear_mark(Ring *), ring_mark(Ring *);