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- /*
- * Copyright (c) 1988 Regents of the University of California.
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms are permitted provided
- * that: (1) source distributions retain this entire copyright notice and
- * comment, and (2) distributions including binaries display the following
- * acknowledgement: ``This product includes software developed by the
- * University of California, Berkeley and its contributors'' in the
- * documentation or other materials provided with the distribution and in
- * all advertising materials mentioning features or use of this software.
- * 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 ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
- * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
- * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
- *
- * @(#)ring.h 5.1 (Berkeley) 9/14/90
- */
-
- /*
- * This defines a structure for a ring buffer.
- *
- * The circular buffer has two parts:
- *(((
- * full: [consume, supply)
- * empty: [supply, consume)
- *]]]
- *
- */
- typedef struct {
- 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) */
- 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 */
-
-
- #if defined(LINT_ARGS)
-
- /* Initialization routine */
- extern int
- ring_init(Ring *ring, char *buffer, int count);
-
- /* Data movement routines */
- extern void
- ring_supply_data(Ring *ring, char *buffer, int count);
- #ifdef notdef
- extern void
- ring_consume_data(Ring *ring, 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_empty_count(Ring *ring),
- ring_empty_consecutive(Ring *ring),
- ring_full_count(Ring *ring),
- ring_full_consecutive(Ring *ring);
-
- #else /* LINT_ARGS */
- extern int
- ring_init();
-
- extern void
- ring_supply_data();
- #ifdef notdef
- extern void
- ring_consume_data();
- #endif
-
- extern void
- ring_supplied(),
- ring_consumed();
-
- extern void
- ring_clear_mark(),
- ring_mark();
-
- extern int
- ring_empty_count(),
- ring_empty_consecutive(),
- ring_full_count(),
- ring_full_consecutive();
- #endif /* defined(LINT_ARGS) */
-