midiq.h revision 330897 
1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2003 Mathew Kanner
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: stable/11/sys/dev/sound/midi/midiq.h 330897 2018-03-14 03:19:51Z eadler $
29 */
30
31#ifndef MIDIQ_H
32#define MIDIQ_H
33
34#define MIDIQ_MOVE(a,b,c) bcopy(b,a,c)
35
36#define MIDIQ_HEAD(name, type)          \
37struct name {                           \
38        int h, t, s;                    \
39        type * b;                        \
40}
41
42#define MIDIQ_INIT(head, buf, size) do {                \
43        (head).h=(head).t=0;                          \
44        (head).s=size;                                 \
45        (head).b=buf;                                  \
46} while (0)
47
48#define MIDIQ_EMPTY(head)       ((head).h == (head).t )
49
50#define MIDIQ_LENBASE(head)         ((head).h - (head).t < 0 ? \
51                                        (head).h - (head).t + (head).s : \
52                                        (head).h - (head).t)
53
54#define MIDIQ_FULL(head)        ((head).h == -1)
55#define MIDIQ_AVAIL(head)       (MIDIQ_FULL(head) ? 0 : (head).s - MIDIQ_LENBASE(head))
56#define MIDIQ_LEN(head)		((head).s - MIDIQ_AVAIL(head))
57#define MIDIQ_DEBUG 0
58/*
59 * No protection against overflow, underflow
60 */
61#define MIDIQ_ENQ(head, buf, size) do {                                                                 \
62		if(MIDIQ_DEBUG)\
63                	printf("#1 %p %p bytes copied %jd tran req s %d h %d t %d\n",            \
64			       &(head).b[(head).h], (buf),                                        \
65			       (intmax_t)(sizeof(*(head).b) *                                     \
66					  MIN( (size), (head).s - (head).h) ),                   \
67			       (size), (head).h, (head).t);               \
68                MIDIQ_MOVE(&(head).b[(head).h], (buf), sizeof(*(head).b) * MIN((size), (head).s - (head).h));                       \
69                if( (head).s - (head).h < (size) ) {                                                    \
70			if(MIDIQ_DEBUG) \
71                        	printf("#2 %p %p bytes copied %jd\n",  (head).b, (buf) + (head).s - (head).h, (intmax_t)sizeof(*(head).b) * ((size) - (head).s + (head).h) );      \
72                        MIDIQ_MOVE((head).b, (buf) + (head).s - (head).h, sizeof(*(head).b) * ((size) - (head).s + (head).h) );      \
73		} \
74                (head).h+=(size);                                                                         \
75                (head).h%=(head).s;                                                                     \
76		if(MIDIQ_EMPTY(head)) (head).h=-1; \
77		if(MIDIQ_DEBUG)\
78                	printf("#E h %d t %d\n", (head).h, (head).t);                       \
79} while (0)
80
81#define MIDIQ_DEQ_I(head, buf, size, move, update) do {                                                                 \
82		if(MIDIQ_FULL(head)) (head).h=(head).t; \
83		if(MIDIQ_DEBUG)\
84                	printf("#1 %p %p bytes copied %jd tran req s %d h %d t %d\n", &(head).b[(head).t], (buf), (intmax_t)sizeof(*(head).b) * MIN((size), (head).s - (head).t), (size), (head).h, (head).t);                       \
85                if (move) MIDIQ_MOVE((buf), &(head).b[(head).t], sizeof(*(head).b) * MIN((size), (head).s - (head).t));                       \
86                if( (head).s - (head).t < (size) ) {                                                    \
87			if(MIDIQ_DEBUG) \
88                        	printf("#2 %p %p bytes copied %jd\n",  (head).b, (buf) + (head).s - (head).t, (intmax_t)sizeof(*(head).b) * ((size) - (head).s + (head).t) );      \
89                        if (move) MIDIQ_MOVE((buf) + (head).s - (head).t, (head).b, sizeof(*(head).b) * ((size) - (head).s + (head).t) );      \
90		} \
91		if (update) { \
92                (head).t+=(size);                                                                         \
93                (head).t%=(head).s;                                                                     \
94		} else { \
95		  if (MIDIQ_EMPTY(head)) (head).h=-1; \
96		} \
97		if(MIDIQ_DEBUG)\
98                	printf("#E h %d t %d\n", (head).h, (head).t);                       \
99} while (0)
100
101#define MIDIQ_SIZE(head) ((head).s)
102#define MIDIQ_CLEAR(head) ((head).h = (head).t = 0)
103#define MIDIQ_BUF(head) ((head).b)
104#define MIDIQ_DEQ(head, buf, size) MIDIQ_DEQ_I(head, buf, size, 1, 1)
105#define MIDIQ_PEEK(head, buf, size) MIDIQ_DEQ_I(head, buf, size, 1, 0)
106#define MIDIQ_POP(head, size) MIDIQ_DEQ_I(head, &head, size, 0, 1)
107
108#endif
109