newlib/winsup/cygwin/sysconf.cc

114 lines
2.6 KiB
C++

/* sysconf.cc
Copyright 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003 Red Hat, Inc.
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#include "winsup.h"
#include <unistd.h>
#include <time.h>
#include <limits.h>
#include <ntdef.h>
#include "security.h"
#include "fhandler.h"
#include "path.h"
#include "dtable.h"
#include "cygerrno.h"
#include "cygheap.h"
#include "ntdll.h"
/* sysconf: POSIX 4.8.1.1 */
/* Allows a portable app to determine quantities of resources or
presence of an option at execution time. */
long int
sysconf (int in)
{
switch (in)
{
case _SC_ARG_MAX:
/* FIXME: what's the right value? _POSIX_ARG_MAX is only 4K */
return 1048576;
case _SC_OPEN_MAX:
{
long max = getdtablesize ();
if (max < OPEN_MAX)
max = OPEN_MAX;
return max;
}
case _SC_PAGESIZE:
return getpagesize ();
case _SC_CLK_TCK:
return CLOCKS_PER_SEC;
case _SC_JOB_CONTROL:
return _POSIX_JOB_CONTROL;
case _SC_CHILD_MAX:
return CHILD_MAX;
case _SC_NGROUPS_MAX:
return NGROUPS_MAX;
case _SC_SAVED_IDS:
return _POSIX_SAVED_IDS;
case _SC_LOGIN_NAME_MAX:
case _SC_GETPW_R_SIZE_MAX:
case _SC_GETGR_R_SIZE_MAX:
return 16*1024;
case _SC_VERSION:
return _POSIX_VERSION;
#if 0 /* FIXME -- unimplemented */
case _SC_TZNAME_MAX:
return _POSIX_TZNAME_MAX;
case _SC_STREAM_MAX:
return _POSIX_STREAM_MAX;
#endif
case _SC_NPROCESSORS_CONF:
case _SC_NPROCESSORS_ONLN:
if (!wincap.supports_smp ())
return 1;
/*FALLTHRU*/
case _SC_PHYS_PAGES:
case _SC_AVPHYS_PAGES:
if (wincap.supports_smp ())
{
NTSTATUS ret;
SYSTEM_BASIC_INFORMATION sbi;
if ((ret = NtQuerySystemInformation (SystemBasicInformation,
(PVOID) &sbi,
sizeof sbi, NULL))
!= STATUS_SUCCESS)
{
__seterrno_from_win_error (RtlNtStatusToDosError (ret));
debug_printf ("NtQuerySystemInformation: ret = %d, "
"Dos(ret) = %d",
ret, RtlNtStatusToDosError (ret));
return -1;
}
switch (in)
{
case _SC_NPROCESSORS_CONF:
return sbi.NumberProcessors;
case _SC_NPROCESSORS_ONLN:
{
int i = 0;
do
if (sbi.ActiveProcessors & 1)
i++;
while (sbi.ActiveProcessors >>= 1);
return i;
}
case _SC_PHYS_PAGES:
return sbi.NumberOfPhysicalPages;
case _SC_AVPHYS_PAGES:
return sbi.HighestPhysicalPage - sbi.LowestPhysicalPage + 1;
}
}
break;
}
/* Invalid input or unimplemented sysconf name */
set_errno (EINVAL);
return -1;
}