1 /* 2 * Copyright (c) 2006 Damien Miller. All rights reserved. 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 RCSID("$OpenBSD: atomicio.c,v 1.10 2001/05/08 22:48:07 markus Exp $"); 30 31 #pragma ident "%Z%%M% %I% %E% SMI" 32 33 #include "atomicio.h" 34 35 /* 36 * ensure all of data on socket comes through. f==read || f==write 37 */ 38 ssize_t 39 atomicio(f, fd, _s, n) 40 ssize_t (*f) (); 41 int fd; 42 void *_s; 43 size_t n; 44 { 45 char *s = _s; 46 ssize_t res, pos = 0; 47 48 while (n > pos) { 49 res = (f) (fd, s + pos, n - pos); 50 switch (res) { 51 case -1: 52 #ifdef EWOULDBLOCK 53 if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK) 54 #else 55 if (errno == EINTR || errno == EAGAIN) 56 #endif 57 continue; 58 /* FALLTHROUGH */ 59 case 0: 60 return (res); 61 default: 62 pos += res; 63 } 64 } 65 return (pos); 66 } 67 68 /* 69 * ensure all of data on socket comes through. f==readv || f==writev 70 */ 71 size_t 72 atomiciov(ssize_t (*f) (int, const struct iovec *, int), int fd, 73 const struct iovec *_iov, int iovcnt) 74 { 75 size_t pos = 0, rem; 76 ssize_t res; 77 struct iovec iov_array[IOV_MAX], *iov = iov_array; 78 79 if (iovcnt > IOV_MAX) { 80 errno = EINVAL; 81 return 0; 82 } 83 /* Make a copy of the iov array because we may modify it below */ 84 memcpy(iov, _iov, iovcnt * sizeof(*_iov)); 85 86 for (; iovcnt > 0 && iov[0].iov_len > 0;) { 87 res = (f) (fd, iov, iovcnt); 88 switch (res) { 89 case -1: 90 if (errno == EINTR || errno == EAGAIN) 91 continue; 92 return 0; 93 case 0: 94 errno = EPIPE; 95 return pos; 96 default: 97 rem = (size_t)res; 98 pos += rem; 99 /* skip completed iov entries */ 100 while (iovcnt > 0 && rem >= iov[0].iov_len) { 101 rem -= iov[0].iov_len; 102 iov++; 103 iovcnt--; 104 } 105 /* This shouldn't happen... */ 106 if (rem > 0 && (iovcnt <= 0 || rem > iov[0].iov_len)) { 107 errno = EFAULT; 108 return 0; 109 } 110 if (iovcnt == 0) 111 break; 112 /* update pointer in partially complete iov */ 113 iov[0].iov_base = ((char *)iov[0].iov_base) + rem; 114 iov[0].iov_len -= rem; 115 } 116 } 117 return pos; 118 } 119