1 /* $NetBSD: ring.h,v 1.10 2003/08/07 11:16:10 agc Exp $ */
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31 * from: @(#)ring.h 8.1 (Berkeley) 6/6/93
34 #include <sys/cdefs.h>
37 * This defines a structure for a ring buffer.
39 * The circular buffer has two parts:
41 * full: [consume, supply)
42 * empty: [supply, consume)
47 unsigned char *consume
, /* where data comes out of */
48 *supply
, /* where data comes in to */
49 *bottom
, /* lowest address in buffer */
50 *top
, /* highest address+1 in buffer */
51 *mark
; /* marker (user defined) */
53 unsigned char *clearto
; /* Data to this point is clear text */
54 unsigned char *encryyptedto
; /* Data is encrypted to here */
55 #endif /* ENCRYPTION */
56 int size
; /* size in bytes of buffer */
57 u_long consumetime
, /* help us keep straight full, empty, etc. */
61 /* Ring buffer structures which are shared */
69 /* Here are some functions and macros to deal with the ring buffer */
71 /* Initialization routine */
73 ring_init(Ring
*ring
, unsigned char *buffer
, int count
);
75 /* Data movement routines */
77 ring_supply_data(Ring
*ring
, unsigned char *buffer
, int count
);
80 ring_consume_data(Ring
*ring
, unsigned char *buffer
, int count
);
83 /* Buffer state transition routines */
85 ring_supplied(Ring
*ring
, int count
),
86 ring_consumed(Ring
*ring
, int count
);
88 /* Buffer state query routines */
90 ring_empty_count(Ring
*ring
),
91 ring_empty_consecutive(Ring
*ring
),
92 ring_full_count(Ring
*ring
),
93 ring_full_consecutive(Ring
*ring
),
94 ring_at_mark(Ring
*ring
);
98 ring_encrypt(Ring
*ring
, void (*func
)(unsigned char *, int)),
99 ring_clearto(Ring
*ring
);
100 #endif /* ENCRYPTION */
103 ring_clear_mark(Ring
*ring
),
104 ring_mark(Ring
*ring
);