/* $OpenBSD: atomicio.c,v 1.28 2016/07/27 23:18:12 djm 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 "includes.h" #include <sys/param.h> #include <sys/uio.h> #include <errno.h> #ifdef HAVE_POLL_H #include <poll.h> #else # ifdef HAVE_SYS_POLL_H # include <sys/poll.h> # endif #endif #include <string.h> #include <unistd.h> #include <limits.h> #include "atomicio.h" /* * ensure all of data on socket comes through. f==read || f==vwrite */ size_t atomicio6(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n, int (*cb)(void *, size_t), void *cb_arg) { char *s = _s; size_t pos = 0; ssize_t res; struct pollfd pfd; #ifndef BROKEN_READ_COMPARISON pfd.fd = fd; pfd.events = f == read ? POLLIN : POLLOUT; #endif while (n > pos) { res = (f) (fd, s + pos, n - pos); switch (res) { case -1: if (errno == EINTR) continue; if (errno == EAGAIN || errno == EWOULDBLOCK) { #ifndef BROKEN_READ_COMPARISON (void)poll(&pfd, 1, -1); #endif continue; } return 0; case 0: errno = EPIPE; return pos; default: pos += (size_t)res; if (cb != NULL && cb(cb_arg, (size_t)res) == -1) { errno = EINTR; return pos; } } } return pos; } size_t atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n) { return atomicio6(f, fd, _s, n, NULL, NULL); } /* * ensure all of data on socket comes through. f==readv || f==writev */ size_t atomiciov6(ssize_t (*f) (int, const struct iovec *, int), int fd, const struct iovec *_iov, int iovcnt, int (*cb)(void *, size_t), void *cb_arg) { size_t pos = 0, rem; ssize_t res; struct iovec iov_array[IOV_MAX], *iov = iov_array; struct pollfd pfd; if (iovcnt < 0 || iovcnt > IOV_MAX) { errno = EINVAL; return 0; } /* Make a copy of the iov array because we may modify it below */ memcpy(iov, _iov, (size_t)iovcnt * sizeof(*_iov)); #ifndef BROKEN_READV_COMPARISON pfd.fd = fd; pfd.events = f == readv ? POLLIN : POLLOUT; #endif for (; iovcnt > 0 && iov[0].iov_len > 0;) { res = (f) (fd, iov, iovcnt); switch (res) { case -1: if (errno == EINTR) continue; if (errno == EAGAIN || errno == EWOULDBLOCK) { #ifndef BROKEN_READV_COMPARISON (void)poll(&pfd, 1, -1); #endif continue; } return 0; case 0: errno = EPIPE; return pos; default: rem = (size_t)res; pos += rem; /* skip completed iov entries */ while (iovcnt > 0 && rem >= iov[0].iov_len) { rem -= iov[0].iov_len; iov++; iovcnt--; } /* This shouldn't happen... */ if (rem > 0 && (iovcnt <= 0 || rem > iov[0].iov_len)) { errno = EFAULT; return 0; } if (iovcnt == 0) break; /* update pointer in partially complete iov */ iov[0].iov_base = ((char *)iov[0].iov_base) + rem; iov[0].iov_len -= rem; } if (cb != NULL && cb(cb_arg, (size_t)res) == -1) { errno = EINTR; return pos; } } return pos; } size_t atomiciov(ssize_t (*f) (int, const struct iovec *, int), int fd, const struct iovec *_iov, int iovcnt) { return atomiciov6(f, fd, _iov, iovcnt, NULL, NULL); }