1 /* $OpenBSD: atomicio.c,v 1.30 2019/01/24 02:42:23 dtucker Exp $ */
3 * Copyright (c) 2006 Damien Miller. All rights reserved.
4 * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved.
5 * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 #include <sys/param.h>
38 # ifdef HAVE_SYS_POLL_H
39 # include <sys/poll.h>
49 * ensure all of data on socket comes through. f==read || f==vwrite
52 atomicio6(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n,
53 int (*cb)(void *, size_t), void *cb_arg)
61 #ifndef BROKEN_READ_COMPARISON
62 pfd.events = f == read ? POLLIN : POLLOUT;
64 pfd.events = POLLIN|POLLOUT;
67 res = (f) (fd, s + pos, n - pos);
71 /* possible SIGALARM, update callback */
72 if (cb != NULL && cb(cb_arg, 0) == -1) {
77 } else if (errno == EAGAIN || errno == EWOULDBLOCK) {
78 (void)poll(&pfd, 1, -1);
87 if (cb != NULL && cb(cb_arg, (size_t)res) == -1) {
97 atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
99 return atomicio6(f, fd, _s, n, NULL, NULL);
103 * ensure all of data on socket comes through. f==readv || f==writev
106 atomiciov6(ssize_t (*f) (int, const struct iovec *, int), int fd,
107 const struct iovec *_iov, int iovcnt,
108 int (*cb)(void *, size_t), void *cb_arg)
112 struct iovec iov_array[IOV_MAX], *iov = iov_array;
115 if (iovcnt < 0 || iovcnt > IOV_MAX) {
119 /* Make a copy of the iov array because we may modify it below */
120 memcpy(iov, _iov, (size_t)iovcnt * sizeof(*_iov));
123 #ifndef BROKEN_READV_COMPARISON
124 pfd.events = f == readv ? POLLIN : POLLOUT;
126 pfd.events = POLLIN|POLLOUT;
128 for (; iovcnt > 0 && iov[0].iov_len > 0;) {
129 res = (f) (fd, iov, iovcnt);
132 if (errno == EINTR) {
133 /* possible SIGALARM, update callback */
134 if (cb != NULL && cb(cb_arg, 0) == -1) {
139 } else if (errno == EAGAIN || errno == EWOULDBLOCK) {
140 (void)poll(&pfd, 1, -1);
150 /* skip completed iov entries */
151 while (iovcnt > 0 && rem >= iov[0].iov_len) {
152 rem -= iov[0].iov_len;
156 /* This shouldn't happen... */
157 if (rem > 0 && (iovcnt <= 0 || rem > iov[0].iov_len)) {
163 /* update pointer in partially complete iov */
164 iov[0].iov_base = ((char *)iov[0].iov_base) + rem;
165 iov[0].iov_len -= rem;
167 if (cb != NULL && cb(cb_arg, (size_t)res) == -1) {
176 atomiciov(ssize_t (*f) (int, const struct iovec *, int), int fd,
177 const struct iovec *_iov, int iovcnt)
179 return atomiciov6(f, fd, _iov, iovcnt, NULL, NULL);