1 /* $NetBSD: timed_connect.c,v 1.2 2017/02/14 01:16:49 christos Exp $ */
2
3 /*++
4 /* NAME
5 /* timed_connect 3
6 /* SUMMARY
7 /* connect operation with timeout
8 /* SYNOPSIS
9 /* #include <sys/socket.h>
10 /* #include <timed_connect.h>
11 /*
12 /* int timed_connect(fd, buf, buf_len, timeout)
13 /* int fd;
14 /* struct sockaddr *buf;
15 /* int buf_len;
16 /* int timeout;
17 /* DESCRIPTION
18 /* timed_connect() implement a BSD socket connect() operation that is
19 /* bounded in time.
20 /*
21 /* Arguments:
22 /* .IP fd
23 /* File descriptor in the range 0..FD_SETSIZE. This descriptor
24 /* must be set to non-blocking mode prior to calling timed_connect().
25 /* .IP buf
26 /* Socket address buffer pointer.
27 /* .IP buf_len
28 /* Size of socket address buffer.
29 /* .IP timeout
30 /* The deadline in seconds. This must be a number > 0.
31 /* DIAGNOSTICS
32 /* Panic: interface violations.
33 /* When the operation does not complete within the deadline, the
34 /* result value is -1, and errno is set to ETIMEDOUT.
35 /* All other returns are identical to those of a blocking connect(2)
36 /* operation.
37 /* WARNINGS
38 /* .ad
39 /* .fi
40 /* A common error is to call timed_connect() without enabling
41 /* non-blocking I/O on the socket. In that case, the \fItimeout\fR
42 /* parameter takes no effect.
43 /* LICENSE
44 /* .ad
45 /* .fi
46 /* The Secure Mailer license must be distributed with this software.
47 /* AUTHOR(S)
48 /* Wietse Venema
49 /* IBM T.J. Watson Research
50 /* P.O. Box 704
51 /* Yorktown Heights, NY 10598, USA
52 /*--*/
53
54 /* System library. */
55
56 #include <sys_defs.h>
57 #include <sys/socket.h>
58 #include <errno.h>
59
60 /* Utility library. */
61
62 #include "msg.h"
63 #include "iostuff.h"
64 #include "sane_connect.h"
65 #include "timed_connect.h"
66
67 /* timed_connect - connect with deadline */
68
timed_connect(int sock,struct sockaddr * sa,int len,int timeout)69 int timed_connect(int sock, struct sockaddr *sa, int len, int timeout)
70 {
71 int error;
72 SOCKOPT_SIZE error_len;
73
74 /*
75 * Sanity check. Just like with timed_wait(), the timeout must be a
76 * positive number.
77 */
78 if (timeout <= 0)
79 msg_panic("timed_connect: bad timeout: %d", timeout);
80
81 /*
82 * Start the connection, and handle all possible results.
83 */
84 if (sane_connect(sock, sa, len) == 0)
85 return (0);
86 if (errno != EINPROGRESS)
87 return (-1);
88
89 /*
90 * A connection is in progress. Wait for a limited amount of time for
91 * something to happen. If nothing happens, report an error.
92 */
93 if (write_wait(sock, timeout) < 0)
94 return (-1);
95
96 /*
97 * Something happened. Some Solaris 2 versions have getsockopt() itself
98 * return the error, instead of returning it via the parameter list.
99 */
100 error = 0;
101 error_len = sizeof(error);
102 if (getsockopt(sock, SOL_SOCKET, SO_ERROR, (void *) &error, &error_len) < 0)
103 return (-1);
104 if (error) {
105 errno = error;
106 return (-1);
107 }
108
109 /*
110 * No problems.
111 */
112 return (0);
113 }
114