1 /* $OpenBSD: atomicio.c,v 1.17 2006/04/01 05:51:34 djm Exp $ */ 2 /* 3 * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved. 4 * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 #include "includes.h" 29 30 #include "atomicio.h" 31 32 /* 33 * ensure all of data on socket comes through. f==read || f==vwrite 34 */ 35 size_t 36 atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n) 37 { 38 char *s = _s; 39 size_t pos = 0; 40 ssize_t res; 41 42 while (n > pos) { 43 res = (f) (fd, s + pos, n - pos); 44 switch (res) { 45 case -1: 46 if (errno == EINTR || errno == EAGAIN) 47 continue; 48 return 0; 49 case 0: 50 errno = EPIPE; 51 return pos; 52 default: 53 pos += (size_t)res; 54 } 55 } 56 return (pos); 57 } 58