From fe856aa957978504137c1d425815d4ed8a22be40 Mon Sep 17 00:00:00 2001 From: Ton Voon Date: Wed, 24 Jan 2007 22:47:25 +0000 Subject: 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 --- gl/safe-read.c | 78 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+) create mode 100644 gl/safe-read.c (limited to 'gl/safe-read.c') diff --git a/gl/safe-read.c b/gl/safe-read.c new file mode 100644 index 00000000..b7bf1d5c --- /dev/null +++ b/gl/safe-read.c @@ -0,0 +1,78 @@ +/* An interface to read and write that retries after interrupts. + + Copyright (C) 1993, 1994, 1998, 2002, 2003, 2004, 2005, 2006 Free + Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +#include + +/* Specification. */ +#ifdef SAFE_WRITE +# include "safe-write.h" +#else +# include "safe-read.h" +#endif + +/* Get ssize_t. */ +#include +#include + +#include + +#ifdef EINTR +# define IS_EINTR(x) ((x) == EINTR) +#else +# define IS_EINTR(x) 0 +#endif + +#include + +#ifdef SAFE_WRITE +# define safe_rw safe_write +# define rw write +#else +# define safe_rw safe_read +# define rw read +# undef const +# define const /* empty */ +#endif + +/* Read(write) up to COUNT bytes at BUF from(to) descriptor FD, retrying if + interrupted. Return the actual number of bytes read(written), zero for EOF, + or SAFE_READ_ERROR(SAFE_WRITE_ERROR) upon error. */ +size_t +safe_rw (int fd, void const *buf, size_t count) +{ + /* Work around a bug in Tru64 5.1. Attempting to read more than + INT_MAX bytes fails with errno == EINVAL. See + . + When decreasing COUNT, keep it block-aligned. */ + enum { BUGGY_READ_MAXIMUM = INT_MAX & ~8191 }; + + for (;;) + { + ssize_t result = rw (fd, buf, count); + + if (0 <= result) + return result; + else if (IS_EINTR (errno)) + continue; + else if (errno == EINVAL && BUGGY_READ_MAXIMUM < count) + count = BUGGY_READ_MAXIMUM; + else + return result; + } +} -- cgit v1.2.3-74-g34f1