blob: f32ff85baf67abf561ea5ed02b9b3a902bf0aa1d [file] [log] [blame]
Darren Tuckerdc4a7792007-06-25 22:08:10 +10001/* $OpenBSD: atomicio.c,v 1.25 2007/06/25 12:02:27 dtucker 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 Tuckerfebf0f52007-06-25 22:15:12 +100037#endif
Damien Millere3476ed2006-07-24 14:13:33 +100038#include <string.h>
Darren Tuckerab17f7d2007-06-25 19:04:12 +100039#include <unistd.h>
Darren Tucker39972492006-07-12 22:22:46 +100040
Ben Lindstrom226cfa02001-01-22 05:34:40 +000041#include "atomicio.h"
Damien Miller05ec5c61999-12-07 17:03:33 +110042
43/*
Darren Tucker85f04c62003-08-03 00:05:58 +100044 * ensure all of data on socket comes through. f==read || f==vwrite
Damien Miller05ec5c61999-12-07 17:03:33 +110045 */
Damien Millerb253cc42005-05-26 12:23:44 +100046size_t
Damien Miller3db78462006-04-23 12:05:16 +100047atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
Damien Miller05ec5c61999-12-07 17:03:33 +110048{
Damien Miller7684ee12000-03-17 23:40:15 +110049 char *s = _s;
Damien Millerb253cc42005-05-26 12:23:44 +100050 size_t pos = 0;
51 ssize_t res;
Darren Tuckerab17f7d2007-06-25 19:04:12 +100052 struct pollfd pfd;
Damien Miller05ec5c61999-12-07 17:03:33 +110053
Darren Tuckerab17f7d2007-06-25 19:04:12 +100054 pfd.fd = fd;
55 pfd.events = f == read ? POLLIN : POLLOUT;
Damien Miller05ec5c61999-12-07 17:03:33 +110056 while (n > pos) {
Damien Miller5f056372000-04-16 12:31:48 +100057 res = (f) (fd, s + pos, n - pos);
Damien Miller05ec5c61999-12-07 17:03:33 +110058 switch (res) {
59 case -1:
Damien Millerf2fdbe52000-07-08 10:57:08 +100060#ifdef EWOULDBLOCK
Darren Tuckerab17f7d2007-06-25 19:04:12 +100061 if (errno == EINTR || errno == EWOULDBLOCK)
Damien Millerf2fdbe52000-07-08 10:57:08 +100062#else
Darren Tuckerab17f7d2007-06-25 19:04:12 +100063 if (errno == EINTR)
Damien Millerf2fdbe52000-07-08 10:57:08 +100064#endif
Damien Miller05ec5c61999-12-07 17:03:33 +110065 continue;
Darren Tuckerab17f7d2007-06-25 19:04:12 +100066 if (errno == EAGAIN) {
67 (void)poll(&pfd, 1, -1);
68 continue;
69 }
Damien Millerb253cc42005-05-26 12:23:44 +100070 return 0;
Damien Miller05ec5c61999-12-07 17:03:33 +110071 case 0:
Damien Millerb253cc42005-05-26 12:23:44 +100072 errno = EPIPE;
73 return pos;
Damien Miller05ec5c61999-12-07 17:03:33 +110074 default:
Damien Miller3fd019e2006-03-15 11:29:51 +110075 pos += (size_t)res;
Damien Miller05ec5c61999-12-07 17:03:33 +110076 }
77 }
78 return (pos);
79}
Damien Miller6aa139c2006-04-23 12:06:20 +100080
81/*
82 * ensure all of data on socket comes through. f==readv || f==writev
83 */
84size_t
85atomiciov(ssize_t (*f) (int, const struct iovec *, int), int fd,
86 const struct iovec *_iov, int iovcnt)
87{
88 size_t pos = 0, rem;
89 ssize_t res;
90 struct iovec iov_array[IOV_MAX], *iov = iov_array;
Darren Tuckerab17f7d2007-06-25 19:04:12 +100091 struct pollfd pfd;
Damien Miller6aa139c2006-04-23 12:06:20 +100092
93 if (iovcnt > IOV_MAX) {
94 errno = EINVAL;
95 return 0;
96 }
97 /* Make a copy of the iov array because we may modify it below */
98 memcpy(iov, _iov, iovcnt * sizeof(*_iov));
99
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000100 pfd.fd = fd;
101 pfd.events = f == readv ? POLLIN : POLLOUT;
Damien Miller6aa139c2006-04-23 12:06:20 +1000102 for (; iovcnt > 0 && iov[0].iov_len > 0;) {
103 res = (f) (fd, iov, iovcnt);
104 switch (res) {
105 case -1:
Darren Tucker9e223242007-06-25 19:06:53 +1000106#ifdef EWOULDBLOCK
107 if (errno == EINTR || errno == EWOULDBLOCK)
108#else
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000109 if (errno == EINTR)
Darren Tucker9e223242007-06-25 19:06:53 +1000110#endif
Damien Miller6aa139c2006-04-23 12:06:20 +1000111 continue;
Darren Tuckerab17f7d2007-06-25 19:04:12 +1000112 if (errno == EAGAIN) {
113 (void)poll(&pfd, 1, -1);
114 continue;
115 }
Damien Miller6aa139c2006-04-23 12:06:20 +1000116 return 0;
117 case 0:
118 errno = EPIPE;
119 return pos;
120 default:
121 rem = (size_t)res;
122 pos += rem;
123 /* skip completed iov entries */
124 while (iovcnt > 0 && rem >= iov[0].iov_len) {
125 rem -= iov[0].iov_len;
126 iov++;
127 iovcnt--;
128 }
129 /* This shouldn't happen... */
Damien Millerb5ea7e72006-04-23 12:06:49 +1000130 if (rem > 0 && (iovcnt <= 0 || rem > iov[0].iov_len)) {
Damien Miller6aa139c2006-04-23 12:06:20 +1000131 errno = EFAULT;
132 return 0;
133 }
134 if (iovcnt == 0)
135 break;
136 /* update pointer in partially complete iov */
137 iov[0].iov_base = ((char *)iov[0].iov_base) + rem;
138 iov[0].iov_len -= rem;
139 }
140 }
141 return pos;
142}