usr/src/cmd/cmd-inet/usr.bin/telnet/ring.h

   1 /*
   2  * Copyright 2001-2002 Sun Microsystems, Inc.  All rights reserved.
   3  * Use is subject to license terms.
   4  */
   5
   6 /*
   7  * Copyright (c) 1988, 1993
   8  *      The Regents of the University of California.  All rights reserved.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  * 3. All advertising materials mentioning features or use of this software
  19  *    must display the following acknowledgement:
  20  *      This product includes software developed by the University of
  21  *      California, Berkeley and its contributors.
  22  * 4. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)ring.h      8.1 (Berkeley) 6/6/93
  39  */
  40
  41 #ifndef _RING_H
  42 #define _RING_H
  43
  44 #pragma ident   "%Z%%M% %I%     %E% SMI"
  45
  46 #ifdef  __cplusplus
  47 extern "C" {
  48 #endif
  49
  50 /*
  51  * This defines a structure for a ring buffer.
  52  *
  53  * The circular buffer has two parts:
  54  * (((
  55  *      full:   [consume, supply)
  56  *      empty:  [supply, consume)
  57  * ]]]
  58  *
  59  */
  60 typedef struct {
  61     unsigned char *consume;     /* where data comes out of */
  62     unsigned char *supply;      /* where data comes in to */
  63     unsigned char *bottom;      /* lowest address in buffer */
  64     unsigned char *top;         /* highest address+1 in buffer */
  65     unsigned char *mark;        /* marker (user defined) */
  66     unsigned char *clearto;     /* Data to this point is clear text */
  67     unsigned char *encryyptedto; /* Data is encrypted to here */
  68     int         size;           /* size in bytes of buffer */
  69     ulong_t     consumetime;    /* help us keep straight full, empty, etc. */
  70     ulong_t     supplytime;
  71 } Ring;
  72
  73 /* Here are some functions and macros to deal with the ring buffer */
  74
  75 /* Initialization routine */
  76 extern int ring_init(Ring *ring, unsigned char *buffer, int count);
  77
  78 /* Data movement routines */
  79 extern void ring_supply_data(Ring *ring, unsigned char *buffer, int count);
  80 #ifdef notdef
  81 extern void ring_consume_data(Ring *ring, unsigned char *buffer, int count);
  82 #endif
  83
  84 /* Buffer state transition routines */
  85 extern void ring_supplied(Ring *ring, int count);
  86 extern void ring_consumed(Ring *ring, int count);
  87
  88 /* Buffer state query routines */
  89 extern int ring_at_mark(Ring *ring);
  90 extern int ring_empty_count(Ring *ring);
  91 extern int ring_empty_consecutive(Ring *ring);
  92 extern int ring_full_count(Ring *ring);
  93 extern int ring_full_consecutive(Ring *ring);
  94
  95 extern void ring_encrypt(Ring *ring, void (*func)());
  96 extern void ring_clearto(Ring *ring);
  97
  98 extern void ring_clear_mark();
  99 extern void ring_mark();
 100
 101
 102 #ifdef  __cplusplus
 103 }
 104 #endif
 105
 106 #endif  /* _RING_H */