1 /* $OpenBSD: atomicio.c,v 1.8 2006/02/11 19:31:18 otto Exp $ */ 2 3 /* 4 * Copyright (c) 2005 Anil Madhavapeddy. All rights served. 5 * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 #include <sys/types.h> 30 #include <sys/uio.h> 31 #include <errno.h> 32 #include <unistd.h> 33 #include "atomicio.h" 34 35 /* 36 * ensure all of data on socket comes through. f==read || f==vwrite 37 */ 38 size_t 39 atomicio(f, fd, _s, n) 40 ssize_t (*f) (int, void *, size_t); 41 int fd; 42 void *_s; 43 size_t n; 44 { 45 char *s = _s; 46 size_t pos = 0; 47 ssize_t res; 48 49 while (n > pos) { 50 res = (f) (fd, s + pos, n - pos); 51 switch (res) { 52 case -1: 53 if (errno == EINTR || errno == EAGAIN) 54 continue; 55 return 0; 56 case 0: 57 errno = EPIPE; 58 return pos; 59 default: 60 pos += (size_t)res; 61 } 62 } 63 return pos; 64 } 65