Annotation of src/usr.bin/ssh/atomicio.c, Revision 1.21
1.21 ! stevesk 1: /* $OpenBSD: atomicio.c,v 1.20 2006/07/11 20:07:25 stevesk 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:
29: #include "includes.h"
1.20 stevesk 30:
31: #include <errno.h>
1.21 ! stevesk 32: #include <string.h>
1.1 deraadt 33:
1.8 markus 34: #include "atomicio.h"
1.1 deraadt 35:
36: /*
1.12 avsm 37: * ensure all of data on socket comes through. f==read || f==vwrite
1.1 deraadt 38: */
1.13 avsm 39: size_t
1.17 djm 40: atomicio(ssize_t (*f) (int, void *, size_t), int fd, void *_s, size_t n)
1.1 deraadt 41: {
1.3 markus 42: char *s = _s;
1.13 avsm 43: size_t pos = 0;
44: ssize_t res;
1.1 deraadt 45:
46: while (n > pos) {
47: res = (f) (fd, s + pos, n - pos);
48: switch (res) {
49: case -1:
50: if (errno == EINTR || errno == EAGAIN)
51: continue;
1.13 avsm 52: return 0;
1.1 deraadt 53: case 0:
1.13 avsm 54: errno = EPIPE;
55: return pos;
1.1 deraadt 56: default:
1.14 otto 57: pos += (size_t)res;
1.1 deraadt 58: }
59: }
60: return (pos);
1.18 djm 61: }
62:
63: /*
64: * ensure all of data on socket comes through. f==readv || f==writev
65: */
66: size_t
67: atomiciov(ssize_t (*f) (int, const struct iovec *, int), int fd,
68: const struct iovec *_iov, int iovcnt)
69: {
70: size_t pos = 0, rem;
71: ssize_t res;
72: struct iovec iov_array[IOV_MAX], *iov = iov_array;
73:
74: if (iovcnt > IOV_MAX) {
75: errno = EINVAL;
76: return 0;
77: }
78: /* Make a copy of the iov array because we may modify it below */
79: memcpy(iov, _iov, iovcnt * sizeof(*_iov));
80:
81: for (; iovcnt > 0 && iov[0].iov_len > 0;) {
82: res = (f) (fd, iov, iovcnt);
83: switch (res) {
84: case -1:
85: if (errno == EINTR || errno == EAGAIN)
86: continue;
87: return 0;
88: case 0:
89: errno = EPIPE;
90: return pos;
91: default:
92: rem = (size_t)res;
93: pos += rem;
94: /* skip completed iov entries */
95: while (iovcnt > 0 && rem >= iov[0].iov_len) {
96: rem -= iov[0].iov_len;
97: iov++;
98: iovcnt--;
99: }
100: /* This shouldn't happen... */
1.19 djm 101: if (rem > 0 && (iovcnt <= 0 || rem > iov[0].iov_len)) {
1.18 djm 102: errno = EFAULT;
103: return 0;
104: }
105: if (iovcnt == 0)
106: break;
107: /* update pointer in partially complete iov */
108: iov[0].iov_base = ((char *)iov[0].iov_base) + rem;
109: iov[0].iov_len -= rem;
110: }
111: }
112: return pos;
1.1 deraadt 113: }