New upstream version 2.3.4
This commit is contained in:
parent
e7bdd1c6c6
commit
de72f6f588
556 changed files with 90432 additions and 53391 deletions
124
gl/getdtablesize.c
Normal file
124
gl/getdtablesize.c
Normal file
|
@ -0,0 +1,124 @@
|
|||
/* getdtablesize() function: Return maximum possible file descriptor value + 1.
|
||||
Copyright (C) 2008-2023 Free Software Foundation, Inc.
|
||||
Written by Bruno Haible <bruno@clisp.org>, 2008.
|
||||
|
||||
This file is free software: you can redistribute it and/or modify
|
||||
it under the terms of the GNU Lesser General Public License as
|
||||
published by the Free Software Foundation; either version 2.1 of the
|
||||
License, or (at your option) any later version.
|
||||
|
||||
This file 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 Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public License
|
||||
along with this program. If not, see <https://www.gnu.org/licenses/>. */
|
||||
|
||||
#include <config.h>
|
||||
|
||||
/* Specification. */
|
||||
#include <unistd.h>
|
||||
|
||||
#if defined _WIN32 && ! defined __CYGWIN__
|
||||
|
||||
# include <stdio.h>
|
||||
|
||||
# if HAVE_MSVC_INVALID_PARAMETER_HANDLER
|
||||
# include "msvc-inval.h"
|
||||
# endif
|
||||
|
||||
# if HAVE_MSVC_INVALID_PARAMETER_HANDLER
|
||||
static int
|
||||
_setmaxstdio_nothrow (int newmax)
|
||||
{
|
||||
int result;
|
||||
|
||||
TRY_MSVC_INVAL
|
||||
{
|
||||
result = _setmaxstdio (newmax);
|
||||
}
|
||||
CATCH_MSVC_INVAL
|
||||
{
|
||||
result = -1;
|
||||
}
|
||||
DONE_MSVC_INVAL;
|
||||
|
||||
return result;
|
||||
}
|
||||
# else
|
||||
# define _setmaxstdio_nothrow _setmaxstdio
|
||||
# endif
|
||||
|
||||
/* Cache for the previous getdtablesize () result. Safe to cache because
|
||||
Windows also lacks setrlimit. */
|
||||
static int dtablesize;
|
||||
|
||||
int
|
||||
getdtablesize (void)
|
||||
{
|
||||
if (dtablesize == 0)
|
||||
{
|
||||
/* We are looking for the number N such that the valid file descriptors
|
||||
are 0..N-1. It can be obtained through a loop as follows:
|
||||
{
|
||||
int fd;
|
||||
for (fd = 3; fd < 65536; fd++)
|
||||
if (dup2 (0, fd) == -1)
|
||||
break;
|
||||
return fd;
|
||||
}
|
||||
On Windows XP, the result is 2048.
|
||||
The drawback of this loop is that it allocates memory for a libc
|
||||
internal array that is never freed.
|
||||
|
||||
The number N can also be obtained as the upper bound for
|
||||
_getmaxstdio (). _getmaxstdio () returns the maximum number of open
|
||||
FILE objects. The sanity check in _setmaxstdio reveals the maximum
|
||||
number of file descriptors. This too allocates memory, but it is
|
||||
freed when we call _setmaxstdio with the original value. */
|
||||
int orig_max_stdio = _getmaxstdio ();
|
||||
unsigned int bound;
|
||||
for (bound = 0x10000; _setmaxstdio_nothrow (bound) < 0; bound = bound / 2)
|
||||
;
|
||||
_setmaxstdio_nothrow (orig_max_stdio);
|
||||
dtablesize = bound;
|
||||
}
|
||||
return dtablesize;
|
||||
}
|
||||
|
||||
#else
|
||||
|
||||
# include <limits.h>
|
||||
# include <sys/resource.h>
|
||||
|
||||
# ifndef RLIM_SAVED_CUR
|
||||
# define RLIM_SAVED_CUR RLIM_INFINITY
|
||||
# endif
|
||||
# ifndef RLIM_SAVED_MAX
|
||||
# define RLIM_SAVED_MAX RLIM_INFINITY
|
||||
# endif
|
||||
|
||||
# ifdef __CYGWIN__
|
||||
/* Cygwin 1.7.25 auto-increases the RLIMIT_NOFILE soft limit until it
|
||||
hits the compile-time constant hard limit of 3200. We might as
|
||||
well just report the hard limit. */
|
||||
# define rlim_cur rlim_max
|
||||
# endif
|
||||
|
||||
int
|
||||
getdtablesize (void)
|
||||
{
|
||||
struct rlimit lim;
|
||||
|
||||
if (getrlimit (RLIMIT_NOFILE, &lim) == 0
|
||||
&& 0 <= lim.rlim_cur && lim.rlim_cur <= INT_MAX
|
||||
&& lim.rlim_cur != RLIM_INFINITY
|
||||
&& lim.rlim_cur != RLIM_SAVED_CUR
|
||||
&& lim.rlim_cur != RLIM_SAVED_MAX)
|
||||
return lim.rlim_cur;
|
||||
|
||||
return INT_MAX;
|
||||
}
|
||||
|
||||
#endif
|
Loading…
Add table
Add a link
Reference in a new issue