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Damien Miller65e42f82010-09-24 22:15:11 +10001/* $OpenBSD: atomicio.c,v 1.26 2010/09/22 22:58:51 djm Exp $ */
Damien Miller05ec5c61999-12-07 17:03:33 +11002/*
Damien Miller6aa139c2006-04-23 12:06:20 +10003 * Copyright (c) 2006 Damien Miller. All rights reserved.
Damien Millerb253cc42005-05-26 12:23:44 +10004 * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved.
Ben Lindstrom92a2e382001-03-05 06:59:27 +00005 * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved.
Damien Miller05ec5c61999-12-07 17:03:33 +11006 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
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.
16 *
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.
27 */
28
29#include "includes.h"
Damien Miller05ec5c61999-12-07 17:03:33 +110030
Damien Miller8dbffe72006-08-05 11:02:17 +100031#include <sys/param.h>
Damien Millerd7834352006-08-05 12:39:39 +100032#include <sys/uio.h>
Damien Miller8dbffe72006-08-05 11:02:17 +100033
Darren Tucker39972492006-07-12 22:22:46 +100034#include <errno.h>
Darren Tuckerfebf0f52007-06-25 22:15:12 +100035#ifdef HAVE_POLL_H
Darren Tuckerdc4a7792007-06-25 22:08:10 +100036#include <poll.h>
Darren Tucker7c92a652007-09-27 07:00:09 +100037#else
38# ifdef HAVE_SYS_POLL_H
39# include <sys/poll.h>
40# endif
Darren Tuckerfebf0f52007-06-25 22:15:12 +100041#endif
Damien Millere3476ed2006-07-24 14:13:33 +100042#include <string.h>
Darren Tuckerab17f7d2007-06-25 19:04:12 +100043#include <unistd.h>
Darren Tucker39972492006-07-12 22:22:46 +100044
Ben Lindstrom226cfa02001-01-22 05:34:40 +000045#include "atomicio.h"
Damien Miller05ec5c61999-12-07 17:03:33 +110046
47/*
Darren Tucker85f04c62003-08-03 00:05:58 +100048 * ensure all of data on socket comes through. f==read || f==vwrite
Damien Miller05ec5c61999-12-07 17:03:33 +110049 */
Damien Millerb253cc42005-05-26 12:23:44 +100050size_t
Damien Miller65e42f82010-09-24 22:15:11 +100051atomicio6(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n,
52 int (*cb)(void *, size_t), void *cb_arg)
Damien Miller05ec5c61999-12-07 17:03:33 +110053{
Damien Miller7684ee12000-03-17 23:40:15 +110054 char *s = _s;
Damien Millerb253cc42005-05-26 12:23:44 +100055 size_t pos = 0;
56 ssize_t res;
Darren Tuckerab17f7d2007-06-25 19:04:12 +100057 struct pollfd pfd;
Damien Miller05ec5c61999-12-07 17:03:33 +110058
Damien Millerf5bbd3b2014-01-30 11:26:46 +110059#ifndef BROKEN_READ_COMPARISON
Darren Tuckerab17f7d2007-06-25 19:04:12 +100060 pfd.fd = fd;
61 pfd.events = f == read ? POLLIN : POLLOUT;
Damien Millerf5bbd3b2014-01-30 11:26:46 +110062#endif
Damien Miller05ec5c61999-12-07 17:03:33 +110063 while (n > pos) {
Damien Miller5f056372000-04-16 12:31:48 +100064 res = (f) (fd, s + pos, n - pos);
Damien Miller05ec5c61999-12-07 17:03:33 +110065 switch (res) {
66 case -1:
Darren Tuckerab17f7d2007-06-25 19:04:12 +100067 if (errno == EINTR)
Damien Miller05ec5c61999-12-07 17:03:33 +110068 continue;
Damien Millered626b42007-09-21 13:12:49 +100069 if (errno == EAGAIN || errno == EWOULDBLOCK) {
Damien Millerf5bbd3b2014-01-30 11:26:46 +110070#ifndef BROKEN_READ_COMPARISON
Darren Tuckerab17f7d2007-06-25 19:04:12 +100071 (void)poll(&pfd, 1, -1);
Damien Millerf5bbd3b2014-01-30 11:26:46 +110072#endif
Darren Tuckerab17f7d2007-06-25 19:04:12 +100073 continue;
74 }
Damien Millerb253cc42005-05-26 12:23:44 +100075 return 0;
Damien Miller05ec5c61999-12-07 17:03:33 +110076 case 0:
Damien Millerb253cc42005-05-26 12:23:44 +100077 errno = EPIPE;
78 return pos;
Damien Miller05ec5c61999-12-07 17:03:33 +110079 default:
Damien Miller3fd019e2006-03-15 11:29:51 +110080 pos += (size_t)res;
Damien Miller65e42f82010-09-24 22:15:11 +100081 if (cb != NULL && cb(cb_arg, (size_t)res) == -1) {
82 errno = EINTR;
83 return pos;
84 }
Damien Miller05ec5c61999-12-07 17:03:33 +110085 }
86 }
Damien Miller65e42f82010-09-24 22:15:11 +100087 return pos;
88}
89
90size_t
91atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
92{
93 return atomicio6(f, fd, _s, n, NULL, NULL);
Damien Miller05ec5c61999-12-07 17:03:33 +110094}
Damien Miller6aa139c2006-04-23 12:06:20 +100095
96/*
97 * ensure all of data on socket comes through. f==readv || f==writev
98 */
99size_t
Damien Miller65e42f82010-09-24 22:15:11 +1000100atomiciov6(ssize_t (*f) (int, const struct iovec *, int), int fd,
101 const struct iovec *_iov, int iovcnt,
102 int (*cb)(void *, size_t), void *cb_arg)
Damien Miller6aa139c2006-04-23 12:06:20 +1000103{
104 size_t pos = 0, rem;
105 ssize_t res;
106 struct iovec iov_array[IOV_MAX], *iov = iov_array;
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000107 struct pollfd pfd;
Damien Miller6aa139c2006-04-23 12:06:20 +1000108
109 if (iovcnt > IOV_MAX) {
110 errno = EINVAL;
111 return 0;
112 }
113 /* Make a copy of the iov array because we may modify it below */
114 memcpy(iov, _iov, iovcnt * sizeof(*_iov));
115
Damien Miller20d16942008-07-05 09:36:58 +1000116#ifndef BROKEN_READV_COMPARISON
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000117 pfd.fd = fd;
118 pfd.events = f == readv ? POLLIN : POLLOUT;
Damien Miller20d16942008-07-05 09:36:58 +1000119#endif
Damien Miller6aa139c2006-04-23 12:06:20 +1000120 for (; iovcnt > 0 && iov[0].iov_len > 0;) {
121 res = (f) (fd, iov, iovcnt);
122 switch (res) {
123 case -1:
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000124 if (errno == EINTR)
Damien Miller6aa139c2006-04-23 12:06:20 +1000125 continue;
Damien Millered626b42007-09-21 13:12:49 +1000126 if (errno == EAGAIN || errno == EWOULDBLOCK) {
Damien Miller20d16942008-07-05 09:36:58 +1000127#ifndef BROKEN_READV_COMPARISON
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000128 (void)poll(&pfd, 1, -1);
Damien Miller20d16942008-07-05 09:36:58 +1000129#endif
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000130 continue;
131 }
Damien Miller6aa139c2006-04-23 12:06:20 +1000132 return 0;
133 case 0:
134 errno = EPIPE;
135 return pos;
136 default:
137 rem = (size_t)res;
138 pos += rem;
139 /* skip completed iov entries */
140 while (iovcnt > 0 && rem >= iov[0].iov_len) {
141 rem -= iov[0].iov_len;
142 iov++;
143 iovcnt--;
144 }
145 /* This shouldn't happen... */
Damien Millerb5ea7e72006-04-23 12:06:49 +1000146 if (rem > 0 && (iovcnt <= 0 || rem > iov[0].iov_len)) {
Damien Miller6aa139c2006-04-23 12:06:20 +1000147 errno = EFAULT;
148 return 0;
149 }
150 if (iovcnt == 0)
151 break;
152 /* update pointer in partially complete iov */
153 iov[0].iov_base = ((char *)iov[0].iov_base) + rem;
154 iov[0].iov_len -= rem;
155 }
Damien Miller65e42f82010-09-24 22:15:11 +1000156 if (cb != NULL && cb(cb_arg, (size_t)res) == -1) {
157 errno = EINTR;
158 return pos;
159 }
Damien Miller6aa139c2006-04-23 12:06:20 +1000160 }
161 return pos;
162}
Damien Miller65e42f82010-09-24 22:15:11 +1000163
164size_t
165atomiciov(ssize_t (*f) (int, const struct iovec *, int), int fd,
166 const struct iovec *_iov, int iovcnt)
167{
168 return atomiciov6(f, fd, _iov, iovcnt, NULL, NULL);
169}