freebsd-skq/contrib/gnu-sort/lib/physmem.c

95 lines
2.4 KiB
C

/* Calculate the size of physical memory.
Copyright 2000, 2001 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
/* Written by Paul Eggert. */
#if HAVE_CONFIG_H
# include <config.h>
#endif
#include "physmem.h"
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
#if HAVE_SYS_PSTAT_H
# include <sys/pstat.h>
#endif
/* Return the total amount of physical memory. */
double
physmem_total (void)
{
#if defined _SC_PHYS_PAGES && defined _SC_PAGESIZE
{
double pages = sysconf (_SC_PHYS_PAGES);
double pagesize = sysconf (_SC_PAGESIZE);
if (0 <= pages && 0 <= pagesize)
return pages * pagesize;
}
#endif
#if HAVE_PSTAT_GETSTATIC
{
struct pst_static pss;
if (0 <= pstat_getstatic (&pss, sizeof pss, 1, 0))
{
double pages = pss.physical_memory;
double pagesize = pss.page_size;
if (0 <= pages && 0 <= pagesize)
return pages * pagesize;
}
}
#endif
/* Guess 64 MB. It's probably an older host, so guess small. */
return 64 * 1024 * 1024;
}
/* Return the amount of physical memory available. */
double
physmem_available (void)
{
#if defined _SC_AVPHYS_PAGES && defined _SC_PAGESIZE
{
double pages = sysconf (_SC_AVPHYS_PAGES);
double pagesize = sysconf (_SC_PAGESIZE);
if (0 <= pages && 0 <= pagesize)
return pages * pagesize;
}
#endif
#if HAVE_PSTAT_GETSTATIC && HAVE_PSTAT_GETDYNAMIC
{
struct pst_static pss;
struct pst_dynamic psd;
if (0 <= pstat_getstatic (&pss, sizeof pss, 1, 0)
&& 0 <= pstat_getdynamic (&psd, sizeof psd, 1, 0))
{
double pages = psd.psd_free;
double pagesize = pss.page_size;
if (0 <= pages && 0 <= pagesize)
return pages * pagesize;
}
}
#endif
/* Guess 25% of physical memory. */
return physmem_total () / 4;
}