glibc/nptl/alloca_cutoff.c

37 lines
1.4 KiB
C

/* Determine whether block of given size can be allocated on the stack or not.
Copyright (C) 2002-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library 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.
The GNU C Library 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 the GNU C Library; see the file COPYING.LIB. If
not, see <http://www.gnu.org/licenses/>. */
#include <alloca.h>
#include <stdlib.h>
#include <sys/param.h>
#include <pthreadP.h>
int
__libc_alloca_cutoff (size_t size)
{
return size <= (MIN (__MAX_ALLOCA_CUTOFF,
THREAD_GETMEM (THREAD_SELF, stackblock_size) / 4
/* The main thread, before the thread library is
initialized, has zero in the stackblock_size
element. Since it is the main thread we can
assume the maximum available stack space. */
?: __MAX_ALLOCA_CUTOFF * 4));
}
libc_hidden_def (__libc_alloca_cutoff)