2 * Copyright (c) 1988, 1993
3 * The Regents of the University of California. All rights reserved.
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15 * This product includes software developed by the University of
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33 * @(#)ring.h 8.1 (Berkeley) 6/6/93
36 /* $Id: ring.h 7853 2000-02-06 05:15:47Z assar $ */
39 * This defines a structure for a ring buffer.
41 * The circular buffer has two parts:
43 * full: [consume, supply)
44 * empty: [supply, consume)
49 unsigned char *consume, /* where data comes out of */
50 *supply, /* where data comes in to */
51 *bottom, /* lowest address in buffer */
52 *top, /* highest address+1 in buffer */
53 *mark; /* marker (user defined) */
54 #if defined(ENCRYPTION)
55 unsigned char *clearto; /* Data to this point is clear text */
56 unsigned char *encryyptedto; /* Data is encrypted to here */
58 int size; /* size in bytes of buffer */
59 u_long consumetime, /* help us keep straight full, empty, etc. */
63 /* Here are some functions and macros to deal with the ring buffer */
65 /* Initialization routine */
67 ring_init (Ring *ring, unsigned char *buffer, int count);
69 /* Data movement routines */
71 ring_supply_data (Ring *ring, unsigned char *buffer, int count);
74 ring_consume_data (Ring *ring, unsigned char *buffer, int count);
77 /* Buffer state transition routines */
79 ring_supplied (Ring *ring, int count),
80 ring_consumed (Ring *ring, int count);
82 /* Buffer state query routines */
84 ring_empty_count (Ring *ring),
85 ring_empty_consecutive (Ring *ring),
86 ring_full_count (Ring *ring),
87 ring_full_consecutive (Ring *ring);
89 #if defined(ENCRYPTION)
91 ring_encrypt (Ring *ring, void (*func)(unsigned char *, int)),
92 ring_clearto (Ring *ring);
95 extern int ring_at_mark(Ring *ring);
98 ring_clear_mark(Ring *ring),
99 ring_mark(Ring *ring);