1*03100a63Svk199839 /* $OpenBSD: atomicio.c,v 1.9 2007/09/07 14:50:44 tobias Exp $ */
2*03100a63Svk199839
3*03100a63Svk199839 /*
4*03100a63Svk199839 * Copyright (c) 2006 Damien Miller. All rights reserved.
5*03100a63Svk199839 * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved.
6*03100a63Svk199839 * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved.
7*03100a63Svk199839 * All rights reserved.
8*03100a63Svk199839 *
9*03100a63Svk199839 * Redistribution and use in source and binary forms, with or without
10*03100a63Svk199839 * modification, are permitted provided that the following conditions
11*03100a63Svk199839 * are met:
12*03100a63Svk199839 * 1. Redistributions of source code must retain the above copyright
13*03100a63Svk199839 * notice, this list of conditions and the following disclaimer.
14*03100a63Svk199839 * 2. Redistributions in binary form must reproduce the above copyright
15*03100a63Svk199839 * notice, this list of conditions and the following disclaimer in the
16*03100a63Svk199839 * documentation and/or other materials provided with the distribution.
17*03100a63Svk199839 *
18*03100a63Svk199839 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19*03100a63Svk199839 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20*03100a63Svk199839 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21*03100a63Svk199839 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22*03100a63Svk199839 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23*03100a63Svk199839 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24*03100a63Svk199839 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25*03100a63Svk199839 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26*03100a63Svk199839 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27*03100a63Svk199839 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28*03100a63Svk199839 */
29*03100a63Svk199839
30*03100a63Svk199839 #pragma ident "%Z%%M% %I% %E% SMI"
31*03100a63Svk199839
32*03100a63Svk199839 #include <sys/param.h>
33*03100a63Svk199839
34*03100a63Svk199839 #include <errno.h>
35*03100a63Svk199839 #include <poll.h>
36*03100a63Svk199839 #include <unistd.h>
37*03100a63Svk199839
38*03100a63Svk199839 #include "atomicio.h"
39*03100a63Svk199839
40*03100a63Svk199839 /*
41*03100a63Svk199839 * ensure all of data on socket comes through. f==read || f==vwrite
42*03100a63Svk199839 */
43*03100a63Svk199839 size_t
atomicio(ssize_t (* f)(int,void *,size_t),int fd,void * _s,size_t n)44*03100a63Svk199839 atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
45*03100a63Svk199839 {
46*03100a63Svk199839 char *s = _s;
47*03100a63Svk199839 size_t pos = 0;
48*03100a63Svk199839 ssize_t res;
49*03100a63Svk199839 struct pollfd pfd;
50*03100a63Svk199839
51*03100a63Svk199839 pfd.fd = fd;
52*03100a63Svk199839 pfd.events = f == read ? POLLIN : POLLOUT;
53*03100a63Svk199839 while (n > pos) {
54*03100a63Svk199839 res = (f) (fd, s + pos, n - pos);
55*03100a63Svk199839 switch (res) {
56*03100a63Svk199839 case -1:
57*03100a63Svk199839 if (errno == EINTR)
58*03100a63Svk199839 continue;
59*03100a63Svk199839 if (errno == EAGAIN) {
60*03100a63Svk199839 (void) poll(&pfd, 1, -1);
61*03100a63Svk199839 continue;
62*03100a63Svk199839 }
63*03100a63Svk199839 return (0);
64*03100a63Svk199839 case 0:
65*03100a63Svk199839 errno = EPIPE;
66*03100a63Svk199839 return (pos);
67*03100a63Svk199839 default:
68*03100a63Svk199839 pos += (size_t)res;
69*03100a63Svk199839 }
70*03100a63Svk199839 }
71*03100a63Svk199839 return (pos);
72*03100a63Svk199839 }
73