xref: /openbsd-src/lib/libutil/imsg.h (revision a0747c9f67a4ae71ccb71e62a28d1ea19e06a63c)
1 /*	$OpenBSD: imsg.h,v 1.6 2021/01/13 09:56:28 claudio Exp $	*/
2 
3 /*
4  * Copyright (c) 2006, 2007 Pierre-Yves Ritschard <pyr@openbsd.org>
5  * Copyright (c) 2006, 2007, 2008 Reyk Floeter <reyk@openbsd.org>
6  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 
21 #ifndef _IMSG_H_
22 #define _IMSG_H_
23 
24 #include <stdint.h>
25 
26 #define IBUF_READ_SIZE		65535
27 #define IMSG_HEADER_SIZE	sizeof(struct imsg_hdr)
28 #define MAX_IMSGSIZE		16384
29 
30 struct ibuf {
31 	TAILQ_ENTRY(ibuf)	 entry;
32 	unsigned char		*buf;
33 	size_t			 size;
34 	size_t			 max;
35 	size_t			 wpos;
36 	size_t			 rpos;
37 	int			 fd;
38 };
39 
40 struct msgbuf {
41 	TAILQ_HEAD(, ibuf)	 bufs;
42 	uint32_t		 queued;
43 	int			 fd;
44 };
45 
46 struct ibuf_read {
47 	unsigned char		 buf[IBUF_READ_SIZE];
48 	unsigned char		*rptr;
49 	size_t			 wpos;
50 };
51 
52 struct imsg_fd {
53 	TAILQ_ENTRY(imsg_fd)	entry;
54 	int			fd;
55 };
56 
57 struct imsgbuf {
58 	TAILQ_HEAD(, imsg_fd)	 fds;
59 	struct ibuf_read	 r;
60 	struct msgbuf		 w;
61 	int			 fd;
62 	pid_t			 pid;
63 };
64 
65 #define IMSGF_HASFD	1
66 
67 struct imsg_hdr {
68 	uint32_t	 type;
69 	uint16_t	 len;
70 	uint16_t	 flags;
71 	uint32_t	 peerid;
72 	uint32_t	 pid;
73 };
74 
75 struct imsg {
76 	struct imsg_hdr	 hdr;
77 	int		 fd;
78 	void		*data;
79 };
80 
81 struct iovec;
82 
83 /* buffer.c */
84 struct ibuf	*ibuf_open(size_t);
85 struct ibuf	*ibuf_dynamic(size_t, size_t);
86 int		 ibuf_add(struct ibuf *, const void *, size_t);
87 void		*ibuf_reserve(struct ibuf *, size_t);
88 void		*ibuf_seek(struct ibuf *, size_t, size_t);
89 size_t		 ibuf_size(struct ibuf *);
90 size_t		 ibuf_left(struct ibuf *);
91 void		 ibuf_close(struct msgbuf *, struct ibuf *);
92 int		 ibuf_write(struct msgbuf *);
93 void		 ibuf_free(struct ibuf *);
94 void		 msgbuf_init(struct msgbuf *);
95 void		 msgbuf_clear(struct msgbuf *);
96 int		 msgbuf_write(struct msgbuf *);
97 void		 msgbuf_drain(struct msgbuf *, size_t);
98 
99 /* imsg.c */
100 void	 imsg_init(struct imsgbuf *, int);
101 ssize_t	 imsg_read(struct imsgbuf *);
102 ssize_t	 imsg_get(struct imsgbuf *, struct imsg *);
103 int	 imsg_compose(struct imsgbuf *, uint32_t, uint32_t, pid_t, int,
104 	    const void *, uint16_t);
105 int	 imsg_composev(struct imsgbuf *, uint32_t, uint32_t,  pid_t, int,
106 	    const struct iovec *, int);
107 struct ibuf *imsg_create(struct imsgbuf *, uint32_t, uint32_t, pid_t, uint16_t);
108 int	 imsg_add(struct ibuf *, const void *, uint16_t);
109 void	 imsg_close(struct imsgbuf *, struct ibuf *);
110 void	 imsg_free(struct imsg *);
111 int	 imsg_flush(struct imsgbuf *);
112 void	 imsg_clear(struct imsgbuf *);
113 
114 #endif
115