xref: /freebsd/sys/dev/sound/midi/midiq.h (revision 405c3050f102b8c74782f0366c8ead927bd07b68)
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  * $FreeBSD$
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)          \
37 struct 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