1*03100a63Svk /* $OpenBSD: atomicio.c,v 1.9 2007/09/07 14:50:44 tobias Exp $ */
2*03100a63Svk
3*03100a63Svk /*
4*03100a63Svk * Copyright (c) 2006 Damien Miller. All rights reserved.
5*03100a63Svk * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved.
6*03100a63Svk * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved.
7*03100a63Svk * All rights reserved.
8*03100a63Svk *
9*03100a63Svk * Redistribution and use in source and binary forms, with or without
10*03100a63Svk * modification, are permitted provided that the following conditions
11*03100a63Svk * are met:
12*03100a63Svk * 1. Redistributions of source code must retain the above copyright
13*03100a63Svk * notice, this list of conditions and the following disclaimer.
14*03100a63Svk * 2. Redistributions in binary form must reproduce the above copyright
15*03100a63Svk * notice, this list of conditions and the following disclaimer in the
16*03100a63Svk * documentation and/or other materials provided with the distribution.
17*03100a63Svk *
18*03100a63Svk * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19*03100a63Svk * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20*03100a63Svk * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21*03100a63Svk * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22*03100a63Svk * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23*03100a63Svk * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24*03100a63Svk * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25*03100a63Svk * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26*03100a63Svk * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27*03100a63Svk * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28*03100a63Svk */
29*03100a63Svk
30*03100a63Svk #include <sys/param.h>
31*03100a63Svk
32*03100a63Svk #include <errno.h>
33*03100a63Svk #include <poll.h>
34*03100a63Svk #include <unistd.h>
35*03100a63Svk
36*03100a63Svk #include "atomicio.h"
37*03100a63Svk
38*03100a63Svk /*
39*03100a63Svk * ensure all of data on socket comes through. f==read || f==vwrite
40*03100a63Svk */
41*03100a63Svk size_t
atomicio(ssize_t (* f)(int,void *,size_t),int fd,void * _s,size_t n)42*03100a63Svk atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
43*03100a63Svk {
44*03100a63Svk char *s = _s;
45*03100a63Svk size_t pos = 0;
46*03100a63Svk ssize_t res;
47*03100a63Svk struct pollfd pfd;
48*03100a63Svk
49*03100a63Svk pfd.fd = fd;
50*03100a63Svk pfd.events = f == read ? POLLIN : POLLOUT;
51*03100a63Svk while (n > pos) {
52*03100a63Svk res = (f) (fd, s + pos, n - pos);
53*03100a63Svk switch (res) {
54*03100a63Svk case -1:
55*03100a63Svk if (errno == EINTR)
56*03100a63Svk continue;
57*03100a63Svk if (errno == EAGAIN) {
58*03100a63Svk (void) poll(&pfd, 1, -1);
59*03100a63Svk continue;
60*03100a63Svk }
61*03100a63Svk return (0);
62*03100a63Svk case 0:
63*03100a63Svk errno = EPIPE;
64*03100a63Svk return (pos);
65*03100a63Svk default:
66*03100a63Svk pos += (size_t)res;
67*03100a63Svk }
68*03100a63Svk }
69*03100a63Svk return (pos);
70*03100a63Svk }
71