/* $OpenBSD: atomicio.c,v 1.11 2012/12/04 02:24:47 deraadt Exp $ */ /* * Copyright (c) 2006 Damien Miller. All rights reserved. * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved. * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ #include <sys/cdefs.h> __RCSID("$NetBSD: atomicio.c,v 1.2 2017/02/06 16:03:40 christos Exp $"); #include <errno.h> #include <poll.h> #include <unistd.h> #include "atomicio.h" /* * ensure all of data on socket comes through. f==read || f==vwrite */ size_t atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n) { char *s = _s; size_t pos = 0; ssize_t res; struct pollfd pfd; pfd.fd = fd; pfd.events = f == read ? POLLIN : POLLOUT; while (n > pos) { res = (f) (fd, s + pos, n - pos); switch (res) { case -1: if (errno == EINTR) continue; if ((errno == EAGAIN) || (errno == ENOBUFS)) { (void)poll(&pfd, 1, -1); continue; } return 0; case 0: errno = EPIPE; return pos; default: pos += (size_t)res; } } return (pos); } |