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authorTon Voon <tonvoon@users.sourceforge.net>2007-01-24 22:47:25 (GMT)
committerTon Voon <tonvoon@users.sourceforge.net>2007-01-24 22:47:25 (GMT)
commitfe856aa957978504137c1d425815d4ed8a22be40 (patch)
treea5bb46ce0e64b2056f75700eadbf27aba7c39418 /gl/safe-read.c
parent210f39bc84cfbb21cd72dc054e43f13815ee0616 (diff)
downloadmonitoring-plugins-fe856aa957978504137c1d425815d4ed8a22be40.tar.gz
Sync with gnulib - lots of extraneous code removed in preference to GNU code
git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@1580 f882894a-f735-0410-b71e-b25c423dba1c
Diffstat (limited to 'gl/safe-read.c')
-rw-r--r--gl/safe-read.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/gl/safe-read.c b/gl/safe-read.c
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1/* An interface to read and write that retries after interrupts.
2
3 Copyright (C) 1993, 1994, 1998, 2002, 2003, 2004, 2005, 2006 Free
4 Software Foundation, Inc.
5
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
9 any later version.
10
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
19
20#include <config.h>
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#include <unistd.h>
32
33#include <errno.h>
34
35#ifdef EINTR
36# define IS_EINTR(x) ((x) == EINTR)
37#else
38# define IS_EINTR(x) 0
39#endif
40
41#include <limits.h>
42
43#ifdef SAFE_WRITE
44# define safe_rw safe_write
45# define rw write
46#else
47# define safe_rw safe_read
48# define rw read
49# undef const
50# define const /* empty */
51#endif
52
53/* Read(write) up to COUNT bytes at BUF from(to) descriptor FD, retrying if
54 interrupted. Return the actual number of bytes read(written), zero for EOF,
55 or SAFE_READ_ERROR(SAFE_WRITE_ERROR) upon error. */
56size_t
57safe_rw (int fd, void const *buf, size_t count)
58{
59 /* Work around a bug in Tru64 5.1. Attempting to read more than
60 INT_MAX bytes fails with errno == EINVAL. See
61 <http://lists.gnu.org/archive/html/bug-gnu-utils/2002-04/msg00010.html>.
62 When decreasing COUNT, keep it block-aligned. */
63 enum { BUGGY_READ_MAXIMUM = INT_MAX & ~8191 };
64
65 for (;;)
66 {
67 ssize_t result = rw (fd, buf, count);
68
69 if (0 <= result)
70 return result;
71 else if (IS_EINTR (errno))
72 continue;
73 else if (errno == EINVAL && BUGGY_READ_MAXIMUM < count)
74 count = BUGGY_READ_MAXIMUM;
75 else
76 return result;
77 }
78}