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authorTon Voon <tonvoon@users.sourceforge.net>2004-12-15 20:47:26 (GMT)
committerTon Voon <tonvoon@users.sourceforge.net>2004-12-15 20:47:26 (GMT)
commit82d1989d3245791c9fac22ca848f5497f261c10b (patch)
tree240017a6fcdcf7ecb5cfb2cbefb57de24de8b7c7 /lib/safe-read.c
parent953a933e4d5900ec3c497781dab26066fef1e78b (diff)
downloadmonitoring-plugins-82d1989d3245791c9fac22ca848f5497f261c10b.tar.gz
Moving m4 files into m4/. Added extra coreutils files required from
autoconf tests. Updated Makefile.am to have nagiosplug lib and a separate coreutils lib git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1027 f882894a-f735-0410-b71e-b25c423dba1c
Diffstat (limited to 'lib/safe-read.c')
-rw-r--r--lib/safe-read.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/lib/safe-read.c b/lib/safe-read.c
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1/* An interface to read and write that retries after interrupts.
2 Copyright (C) 1993, 1994, 1998, 2002-2003 Free Software Foundation, Inc.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
7 any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; if not, write to the Free Software Foundation,
16 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
17
18#if HAVE_CONFIG_H
19# include <config.h>
20#endif
21
22/* Specification. */
23#ifdef SAFE_WRITE
24# include "safe-write.h"
25#else
26# include "safe-read.h"
27#endif
28
29/* Get ssize_t. */
30#include <sys/types.h>
31#if HAVE_UNISTD_H
32# include <unistd.h>
33#endif
34
35#include <errno.h>
36#ifndef errno
37extern int errno;
38#endif
39
40#ifdef EINTR
41# define IS_EINTR(x) ((x) == EINTR)
42#else
43# define IS_EINTR(x) 0
44#endif
45
46#include <limits.h>
47
48#ifdef SAFE_WRITE
49# define safe_rw safe_write
50# define rw write
51#else
52# define safe_rw safe_read
53# define rw read
54# undef const
55# define const /* empty */
56#endif
57
58/* Read(write) up to COUNT bytes at BUF from(to) descriptor FD, retrying if
59 interrupted. Return the actual number of bytes read(written), zero for EOF,
60 or SAFE_READ_ERROR(SAFE_WRITE_ERROR) upon error. */
61size_t
62safe_rw (int fd, void const *buf, size_t count)
63{
64 ssize_t result;
65
66 /* POSIX limits COUNT to SSIZE_MAX, but we limit it further, requiring
67 that COUNT <= INT_MAX, to avoid triggering a bug in Tru64 5.1.
68 When decreasing COUNT, keep the file pointer block-aligned.
69 Note that in any case, read(write) may succeed, yet read(write)
70 fewer than COUNT bytes, so the caller must be prepared to handle
71 partial results. */
72 if (count > INT_MAX)
73 count = INT_MAX & ~8191;
74
75 do
76 {
77 result = rw (fd, buf, count);
78 }
79 while (result < 0 && IS_EINTR (errno));
80
81 return (size_t) result;
82}