1 /*-
2  * Copyright (c) 2003-2005 MAEKAWA Masahide <maekawa@cvsync.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the author nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/types.h>
31 #include <sys/socket.h>
32 
33 #include <stdlib.h>
34 
35 #include <errno.h>
36 #include <poll.h>
37 #include <pthread.h>
38 #include <sched.h>
39 #include <string.h>
40 
41 #include "compat_stdbool.h"
42 
43 #include "logmsg.h"
44 #include "network.h"
45 
46 static struct pollfd *__fds = NULL;
47 static nfds_t __nfds = 0;
48 
49 bool
sock_init(int * socks)50 sock_init(int *socks)
51 {
52 	nfds_t i;
53 
54 	for (i = 0 ; socks[i] != -1 ; i++)
55 		__nfds++;
56 	if (__nfds == 0)
57 		return (false);
58 	if ((__fds = malloc(__nfds * sizeof(*__fds))) == NULL) {
59 		logmsg_err("%s", strerror(errno));
60 		return (false);
61 	}
62 	for (i = 0 ; i < __nfds ; i++) {
63 		__fds[i].fd = socks[i];
64 		__fds[i].events = POLLIN;
65 	}
66 
67 	return (true);
68 }
69 
70 void
sock_destroy(void)71 sock_destroy(void)
72 {
73 	free(__fds);
74 }
75 
76 bool
sock_select(void)77 sock_select(void)
78 {
79 	nfds_t i;
80 
81 	for (i = 0 ; i < __nfds ; i++)
82 		__fds[i].revents = 0;
83 
84 	if (poll(__fds, __nfds, 1000 /* 1sec */) == -1)
85 		return (false);
86 
87 	return (true);
88 }
89 
90 int
sock_accept(void)91 sock_accept(void)
92 {
93 	nfds_t i;
94 	int sock = -1;
95 
96 	for (i = 0 ; i < __nfds ; i++) {
97 		if (!(__fds[i].revents & POLLIN))
98 			continue;
99 
100 		if ((sock = accept(__fds[i].fd, NULL, NULL)) == -1) {
101 			if (errno == EINTR) {
102 				logmsg_intr();
103 				return (-1);
104 			}
105 			if ((errno != EAGAIN) && (errno != EWOULDBLOCK)) {
106 				logmsg_err("%s", strerror(errno));
107 				return (-1);
108 			}
109 			continue;
110 		}
111 
112 		break;
113 	}
114 
115 	return (sock);
116 }
117 
118 bool
sock_wait(int sock,int dir)119 sock_wait(int sock, int dir)
120 {
121 	struct pollfd fds[1];
122 	short events;
123 	int rv;
124 
125 	if (dir == CVSYNC_SOCKDIR_OUT)
126 		events = POLLOUT;
127 	else /* dir == CVSYNC_SOCKDIR_IN */
128 		events = POLLIN;
129 
130 	fds[0].fd = sock;
131 	fds[0].events = events;
132 	fds[0].revents = 0;
133 
134 	for (;;) {
135 		if ((rv = poll(fds, 1, CVSYNC_TICKS)) == -1) {
136 			if (errno != EINTR) {
137 				logmsg_err("Socket Error: poll: %s",
138 					   strerror(errno));
139 				return (false);
140 			}
141 			rv = 0;
142 		}
143 		if (rv == 0) {
144 			if (sched_yield() == -1) {
145 				logmsg_err("Socket Error: yield: %s",
146 					   strerror(errno));
147 			}
148 			continue;
149 		}
150 		if (!(fds[0].revents & events)) {
151 			logmsg_err("Socket Error: poll");
152 			return (false);
153 		}
154 		break;
155 	}
156 
157 	return (true);
158 }
159