xref: /openbsd/lib/libsndio/mio_aucat.c (revision 9b7c3dbb)
1 /*	$OpenBSD: mio_aucat.c,v 1.12 2016/01/09 08:27:24 ratchov Exp $	*/
2 /*
3  * Copyright (c) 2008 Alexandre Ratchov <alex@caoua.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/socket.h>
20 #include <sys/un.h>
21 #include <netinet/in.h>
22 
23 #include <errno.h>
24 #include <fcntl.h>
25 #include <poll.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <unistd.h>
30 
31 #include "aucat.h"
32 #include "debug.h"
33 #include "mio_priv.h"
34 
35 struct mio_aucat_hdl {
36 	struct mio_hdl mio;
37 	struct aucat aucat;
38 	int events;
39 };
40 
41 static void mio_aucat_close(struct mio_hdl *);
42 static size_t mio_aucat_read(struct mio_hdl *, void *, size_t);
43 static size_t mio_aucat_write(struct mio_hdl *, const void *, size_t);
44 static int mio_aucat_nfds(struct mio_hdl *);
45 static int mio_aucat_pollfd(struct mio_hdl *, struct pollfd *, int);
46 static int mio_aucat_revents(struct mio_hdl *, struct pollfd *);
47 
48 static struct mio_ops mio_aucat_ops = {
49 	mio_aucat_close,
50 	mio_aucat_write,
51 	mio_aucat_read,
52 	mio_aucat_nfds,
53 	mio_aucat_pollfd,
54 	mio_aucat_revents
55 };
56 
57 /*
58  * execute the next message, return 0 if blocked
59  */
60 static int
61 mio_aucat_runmsg(struct mio_aucat_hdl *hdl)
62 {
63 	int delta;
64 
65 	if (!_aucat_rmsg(&hdl->aucat, &hdl->mio.eof))
66 		return 0;
67 	switch (ntohl(hdl->aucat.rmsg.cmd)) {
68 	case AMSG_DATA:
69 		return 1;
70 	case AMSG_FLOWCTL:
71 		delta = ntohl(hdl->aucat.rmsg.u.ts.delta);
72 		hdl->aucat.maxwrite += delta;
73 		DPRINTF("aucat: flowctl = %d, maxwrite = %d\n",
74 		    delta, hdl->aucat.maxwrite);
75 		break;
76 	default:
77 		DPRINTF("mio_aucat_runmsg: unhandled message %u\n",
78 		    hdl->aucat.rmsg.cmd);
79 		hdl->mio.eof = 1;
80 		return 0;
81 	}
82 	hdl->aucat.rstate = RSTATE_MSG;
83 	hdl->aucat.rtodo = sizeof(struct amsg);
84 	return 1;
85 }
86 
87 struct mio_hdl *
88 _mio_aucat_open(const char *str, unsigned int mode, int nbio)
89 {
90 	struct mio_aucat_hdl *hdl;
91 
92 	hdl = malloc(sizeof(struct mio_aucat_hdl));
93 	if (hdl == NULL)
94 		return NULL;
95 	if (!_aucat_open(&hdl->aucat, str, mode))
96 		goto bad;
97 	_mio_create(&hdl->mio, &mio_aucat_ops, mode, nbio);
98 	if (!_aucat_setfl(&hdl->aucat, 1, &hdl->mio.eof))
99 		goto bad;
100 	return (struct mio_hdl *)hdl;
101 bad:
102 	free(hdl);
103 	return NULL;
104 }
105 
106 static void
107 mio_aucat_close(struct mio_hdl *sh)
108 {
109 	struct mio_aucat_hdl *hdl = (struct mio_aucat_hdl *)sh;
110 
111 	if (!hdl->mio.eof)
112 		_aucat_setfl(&hdl->aucat, 0, &hdl->mio.eof);
113 	_aucat_close(&hdl->aucat, hdl->mio.eof);
114 	free(hdl);
115 }
116 
117 static size_t
118 mio_aucat_read(struct mio_hdl *sh, void *buf, size_t len)
119 {
120 	struct mio_aucat_hdl *hdl = (struct mio_aucat_hdl *)sh;
121 
122 	while (hdl->aucat.rstate == RSTATE_MSG) {
123 		if (!mio_aucat_runmsg(hdl))
124 			return 0;
125 	}
126 	return _aucat_rdata(&hdl->aucat, buf, len, &hdl->mio.eof);
127 }
128 
129 static size_t
130 mio_aucat_write(struct mio_hdl *sh, const void *buf, size_t len)
131 {
132 	struct mio_aucat_hdl *hdl = (struct mio_aucat_hdl *)sh;
133 	size_t n;
134 
135 	if (len <= 0 || hdl->aucat.maxwrite <= 0)
136 		return 0;
137 	if (len > hdl->aucat.maxwrite)
138 		len = hdl->aucat.maxwrite;
139 	n = _aucat_wdata(&hdl->aucat, buf, len, 1, &hdl->mio.eof);
140 	hdl->aucat.maxwrite -= n;
141 	return n;
142 }
143 
144 static int
145 mio_aucat_nfds(struct mio_hdl *sh)
146 {
147 	return 1;
148 }
149 
150 static int
151 mio_aucat_pollfd(struct mio_hdl *sh, struct pollfd *pfd, int events)
152 {
153 	struct mio_aucat_hdl *hdl = (struct mio_aucat_hdl *)sh;
154 
155 	hdl->events = events;
156 	if (hdl->aucat.maxwrite <= 0)
157 		events &= ~POLLOUT;
158 	return _aucat_pollfd(&hdl->aucat, pfd, events);
159 }
160 
161 static int
162 mio_aucat_revents(struct mio_hdl *sh, struct pollfd *pfd)
163 {
164 	struct mio_aucat_hdl *hdl = (struct mio_aucat_hdl *)sh;
165 	int revents = pfd->revents;
166 
167 	if (revents & POLLIN) {
168 		while (hdl->aucat.rstate == RSTATE_MSG) {
169 			if (!mio_aucat_runmsg(hdl))
170 				break;
171 		}
172 		if (hdl->aucat.rstate != RSTATE_DATA)
173 			revents &= ~POLLIN;
174 	}
175 	if (revents & POLLOUT) {
176 		if (hdl->aucat.maxwrite <= 0)
177 			revents &= ~POLLOUT;
178 	}
179 	if (hdl->mio.eof)
180 		return POLLHUP;
181 	return revents & (hdl->events | POLLHUP);
182 }
183