xref: /freebsd/usr.sbin/bhyve/sockstream.c (revision f126890ac5386406dadf7c4cfa9566cbb56537c5)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2015 Nahanni Systems, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/types.h>
30 #include <unistd.h>
31 
32 #include <errno.h>
33 
34 #include "sockstream.h"
35 
36 ssize_t
37 stream_read(int fd, void *buf, ssize_t nbytes)
38 {
39 	uint8_t *p;
40 	ssize_t len = 0;
41 	ssize_t n;
42 
43 	p = buf;
44 
45 	while (len < nbytes) {
46 		n = read(fd, p + len, nbytes - len);
47 		if (n == 0)
48 			break;
49 
50 		if (n < 0) {
51 			if (errno == EINTR || errno == EAGAIN)
52 				continue;
53 			return (n);
54 		}
55 		len += n;
56 	}
57 	return (len);
58 }
59 
60 ssize_t
61 stream_write(int fd, const void *buf, ssize_t nbytes)
62 {
63 	const uint8_t *p;
64 	ssize_t len = 0;
65 	ssize_t n;
66 
67 	p = buf;
68 
69 	while (len < nbytes) {
70 		n = write(fd, p + len, nbytes - len);
71 		if (n == 0)
72 			break;
73 		if (n < 0) {
74 			if (errno == EINTR || errno == EAGAIN)
75 				continue;
76 			return (n);
77 		}
78 		len += n;
79 	}
80 	return (len);
81 }
82