summaryrefslogtreecommitdiff
path: root/lib/libsndio/amsg.h
blob: 6d1a185fcbfe27d7b0e9952b2991bbdbf244cba6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
/*	$OpenBSD: amsg.h,v 1.15 2022/04/29 08:30:48 ratchov Exp $	*/
/*
 * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
#ifndef AMSG_H
#define AMSG_H

#include <stdint.h>

/*
 * unix-domain socket name is:
 *
 * DIR [ '-' UID ] '/' FILE UNIT
 *
 * example: "/tmp/sndio-1000/sock0"
 *
 */
#define SOCKPATH_DIR	"/tmp/sndio"
#define SOCKPATH_FILE	"sock"
#define SOCKPATH_MAX	(1 +		\
	sizeof(SOCKPATH_DIR) - 1 +	\
	sizeof(char) +			\
	sizeof(int) * 3 +		\
	sizeof(char) +			\
	sizeof(SOCKPATH_FILE) - 1 +	\
	sizeof(int) * 3)

/*
 * server TCP base port number
 */
#define AUCAT_PORT		11025

/*
 * limits
 */
#define AMSG_CTL_NAMEMAX	16	/* max name length */

/*
 * WARNING: since the protocol may be simultaneously used by static
 * binaries or by different versions of a shared library, we are not
 * allowed to change the packet binary representation in a backward
 * incompatible way.
 *
 * Especially, make sure the amsg_xxx structures are not larger
 * than 32 bytes.
 */
struct amsg {
#define AMSG_ACK	0	/* ack for START/STOP */
#define AMSG_GETPAR	1	/* get the current parameters */
#define AMSG_SETPAR	2	/* set the current parameters */
#define AMSG_START	3	/* request the server to start the stream */
#define AMSG_STOP	4	/* request the server to stop the stream */
#define AMSG_DATA	5	/* data block */
#define AMSG_FLOWCTL	6	/* feedback about buffer usage */
#define AMSG_MOVE	7	/* position changed */
#define AMSG_SETVOL	9	/* set volume */
#define AMSG_HELLO	10	/* say hello, check versions and so ... */
#define AMSG_BYE	11	/* ask server to drop connection */
#define AMSG_AUTH	12	/* send authentication cookie */
#define AMSG_CTLSUB	13	/* ondesc/onctl subscription */
#define AMSG_CTLSET	14	/* set control value */
#define AMSG_CTLSYNC	15	/* end of controls descriptions */
	uint32_t cmd;
	uint32_t __pad;
	union {
		struct amsg_par {
			uint8_t legacy_mode;	/* compat for old libs */
			uint8_t xrun;		/* one of above */
			uint8_t bps;		/* bytes per sample */
			uint8_t bits;		/* actually used bits */
			uint8_t msb;		/* 1 if MSB justified */
			uint8_t le;		/* 1 if little endian */
			uint8_t sig;		/* 1 if signed */
			uint8_t __pad1;
			uint16_t pchan;		/* play channels */
			uint16_t rchan;		/* record channels */
			uint32_t rate;		/* frames per second */
			uint32_t bufsz;		/* total buffered frames */
			uint32_t round;
			uint32_t appbufsz;	/* client side bufsz */
			uint32_t _reserved[1];	/* for future use */
		} par;
		struct amsg_data {
#define AMSG_DATAMAX	0x1000
			uint32_t size;
		} data;
		struct amsg_stop {
			uint8_t drain;
		} stop;
		struct amsg_ts {
			int32_t delta;
		} ts;
		struct amsg_vol {
			uint32_t ctl;
		} vol;
		struct amsg_hello {
			uint16_t mode;		/* bitmap of MODE_XXX */
#define AMSG_VERSION	7
			uint8_t version;	/* protocol version */
#define AMSG_NODEV	255
			uint8_t devnum;		/* device number */
			uint32_t id;		/* client id */
#define AMSG_OPTMAX	12
			char opt[AMSG_OPTMAX];	/* profile name */
			char who[12];		/* hint for leases */
		} hello;
		struct amsg_auth {
#define AMSG_COOKIELEN	16
			uint8_t cookie[AMSG_COOKIELEN];
		} auth;
		struct amsg_ctlsub {
			uint8_t desc, val;
		} ctlsub;
		struct amsg_ctlset {
			uint16_t addr, val;
		} ctlset;
	} u;
};

/*
 * network representation of sioctl_node structure
 */
struct amsg_ctl_node {
	char name[AMSG_CTL_NAMEMAX];
	int16_t unit;
	uint8_t __pad[2];
};

/*
 * network representation of sioctl_desc structure
 */
struct amsg_ctl_desc {
	struct amsg_ctl_node node0;	/* affected channels */
	struct amsg_ctl_node node1;	/* dito for AMSG_CTL_{SEL,VEC,LIST} */
	char func[AMSG_CTL_NAMEMAX];	/* parameter function name */
	char group[AMSG_CTL_NAMEMAX];	/* group of the control */
	uint8_t type;			/* see sioctl_desc structure */
	uint8_t __pad1[1];
	uint16_t addr;			/* control address */
	uint16_t maxval;
	uint16_t curval;
	uint32_t __pad2[3];
};

/*
 * Initialize an amsg structure: fill all fields with 0xff, so the read
 * can test which fields were set.
 */
#define AMSG_INIT(m) do { memset((m), 0xff, sizeof(struct amsg)); } while (0)

/*
 * Since the structure is memset to 0xff, the MSB can be used to check
 * if any field was set.
 */
#define AMSG_ISSET(x) (((x) & (1 << (8 * sizeof(x) - 1))) == 0)

#endif /* !defined(AMSG_H) */