Annotation of src/usr.bin/ssh/atomicio.c, Revision 1.29
1.29 ! dtucker 1: /* $OpenBSD: atomicio.c,v 1.28 2016/07/27 23:18:12 djm Exp $ */
1.1 deraadt 2: /*
1.18 djm 3: * Copyright (c) 2006 Damien Miller. All rights reserved.
1.13 avsm 4: * Copyright (c) 2005 Anil Madhavapeddy. All rights reserved.
1.9 deraadt 5: * Copyright (c) 1995,1999 Theo de Raadt. All rights reserved.
1.1 deraadt 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:
1.23 deraadt 29: #include <sys/uio.h>
1.20 stevesk 30:
31: #include <errno.h>
1.25 dtucker 32: #include <poll.h>
1.21 stevesk 33: #include <string.h>
1.24 djm 34: #include <unistd.h>
1.27 deraadt 35: #include <limits.h>
1.1 deraadt 36:
1.8 markus 37: #include "atomicio.h"
1.1 deraadt 38:
39: /*
1.12 avsm 40: * ensure all of data on socket comes through. f==read || f==vwrite
1.1 deraadt 41: */
1.13 avsm 42: size_t
1.26 djm 43: atomicio6(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n,
44: int (*cb)(void *, size_t), void *cb_arg)
1.1 deraadt 45: {
1.3 markus 46: char *s = _s;
1.13 avsm 47: size_t pos = 0;
48: ssize_t res;
1.24 djm 49: struct pollfd pfd;
1.1 deraadt 50:
1.24 djm 51: pfd.fd = fd;
52: pfd.events = f == read ? POLLIN : POLLOUT;
1.1 deraadt 53: while (n > pos) {
54: res = (f) (fd, s + pos, n - pos);
55: switch (res) {
56: case -1:
1.29 ! dtucker 57: switch(errno) {
! 58: case EINTR:
! 59: /* possible SIGALARM, update callback */
! 60: if (cb != NULL && cb(cb_arg, 0) == -1) {
! 61: errno = EINTR;
! 62: return pos;
! 63: }
1.1 deraadt 64: continue;
1.29 ! dtucker 65: case EAGAIN:
1.24 djm 66: (void)poll(&pfd, 1, -1);
67: continue;
68: }
1.13 avsm 69: return 0;
1.1 deraadt 70: case 0:
1.13 avsm 71: errno = EPIPE;
72: return pos;
1.1 deraadt 73: default:
1.14 otto 74: pos += (size_t)res;
1.26 djm 75: if (cb != NULL && cb(cb_arg, (size_t)res) == -1) {
76: errno = EINTR;
77: return pos;
78: }
1.1 deraadt 79: }
80: }
1.26 djm 81: return pos;
82: }
83:
84: size_t
85: atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
86: {
87: return atomicio6(f, fd, _s, n, NULL, NULL);
1.18 djm 88: }
89:
90: /*
91: * ensure all of data on socket comes through. f==readv || f==writev
92: */
93: size_t
1.26 djm 94: atomiciov6(ssize_t (*f) (int, const struct iovec *, int), int fd,
95: const struct iovec *_iov, int iovcnt,
96: int (*cb)(void *, size_t), void *cb_arg)
1.18 djm 97: {
98: size_t pos = 0, rem;
99: ssize_t res;
100: struct iovec iov_array[IOV_MAX], *iov = iov_array;
1.24 djm 101: struct pollfd pfd;
1.18 djm 102:
1.28 djm 103: if (iovcnt < 0 || iovcnt > IOV_MAX) {
1.18 djm 104: errno = EINVAL;
105: return 0;
106: }
107: /* Make a copy of the iov array because we may modify it below */
1.28 djm 108: memcpy(iov, _iov, (size_t)iovcnt * sizeof(*_iov));
1.18 djm 109:
1.24 djm 110: pfd.fd = fd;
111: pfd.events = f == readv ? POLLIN : POLLOUT;
1.18 djm 112: for (; iovcnt > 0 && iov[0].iov_len > 0;) {
113: res = (f) (fd, iov, iovcnt);
114: switch (res) {
115: case -1:
1.29 ! dtucker 116: switch(errno) {
! 117: case EINTR:
! 118: /* possible SIGALARM, update callback */
! 119: if (cb != NULL && cb(cb_arg, 0) == -1) {
! 120: errno = EINTR;
! 121: return pos;
! 122: }
1.24 djm 123: continue;
1.29 ! dtucker 124: case EAGAIN:
1.24 djm 125: (void)poll(&pfd, 1, -1);
1.18 djm 126: continue;
1.24 djm 127: }
1.18 djm 128: return 0;
129: case 0:
130: errno = EPIPE;
131: return pos;
132: default:
133: rem = (size_t)res;
134: pos += rem;
135: /* skip completed iov entries */
136: while (iovcnt > 0 && rem >= iov[0].iov_len) {
137: rem -= iov[0].iov_len;
138: iov++;
139: iovcnt--;
140: }
141: /* This shouldn't happen... */
1.19 djm 142: if (rem > 0 && (iovcnt <= 0 || rem > iov[0].iov_len)) {
1.18 djm 143: errno = EFAULT;
144: return 0;
145: }
146: if (iovcnt == 0)
147: break;
148: /* update pointer in partially complete iov */
149: iov[0].iov_base = ((char *)iov[0].iov_base) + rem;
150: iov[0].iov_len -= rem;
151: }
1.26 djm 152: if (cb != NULL && cb(cb_arg, (size_t)res) == -1) {
153: errno = EINTR;
154: return pos;
155: }
1.18 djm 156: }
157: return pos;
1.26 djm 158: }
159:
160: size_t
161: atomiciov(ssize_t (*f) (int, const struct iovec *, int), int fd,
162: const struct iovec *_iov, int iovcnt)
163: {
164: return atomiciov6(f, fd, _iov, iovcnt, NULL, NULL);
1.1 deraadt 165: }