xref: /freebsd/lib/libsys/recvmmsg.c (revision b59017c5cad90d0f09a59e68c00457b7faf93e7c)
1 /*
2  * Copyright (c) 2016 Boris Astardzhiev, Smartcom-Bulgaria AD
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(s), this list of conditions and the following disclaimer as
10  *    the first lines of this file unmodified other than the possible
11  *    addition of one or more copyright notices.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice(s), this list of conditions and the following disclaimer in
14  *    the documentation and/or other materials provided with the
15  *    distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
21  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
22  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
23  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
24  * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
25  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
26  * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
27  * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 
30 #include <sys/types.h>
31 #include <sys/socket.h>
32 #include <errno.h>
33 #include <poll.h>
34 #include <stddef.h>
35 #include <ssp/ssp.h>
36 #include "libc_private.h"
37 
38 ssize_t
39 __ssp_real(recvmmsg)(int s, struct mmsghdr *__restrict msgvec, size_t vlen,
40     int flags, const struct timespec *__restrict timeout)
41 {
42 	struct pollfd pfd[1];
43 	size_t i, rcvd;
44 	ssize_t ret;
45 	int res;
46 	short ev;
47 
48 	if (timeout != NULL) {
49 		pfd[0].fd = s;
50 		pfd[0].revents = 0;
51 		pfd[0].events = ev = POLLIN | POLLRDNORM | POLLRDBAND |
52 		    POLLPRI;
53 		res = ppoll(&pfd[0], 1, timeout, NULL);
54 		if (res == -1 || res == 0)
55 			return (res);
56 		if (pfd[0].revents & POLLNVAL) {
57 			errno = EBADF;
58 			return (-1);
59 		}
60 		if ((pfd[0].revents & ev) == 0) {
61 			errno = ETIMEDOUT;
62 			return (-1);
63 		}
64 	}
65 
66 	ret = __sys_recvmsg(s, &msgvec[0].msg_hdr, flags);
67 	if (ret == -1)
68 		return (ret);
69 
70 	msgvec[0].msg_len = ret;
71 
72 	/*
73 	 * Do non-blocking receive for second and later messages if
74 	 * WAITFORONE is set.
75 	 */
76 	if (flags & MSG_WAITFORONE)
77 		flags |= MSG_DONTWAIT;
78 
79 	rcvd = 1;
80 	for (i = rcvd; i < vlen; i++, rcvd++) {
81 		ret = __sys_recvmsg(s, &msgvec[i].msg_hdr, flags);
82 		if (ret == -1) {
83 			/* We have received messages. Let caller know
84 			 * about the data received, socket error is
85 			 * returned on next invocation.
86 			 */
87 			return (rcvd);
88 		}
89 
90 		/* Save received bytes. */
91 		msgvec[i].msg_len = ret;
92 	}
93 
94 	return (rcvd);
95 }
96