sysdeps/unix/sysv/linux/getrlimit.c

   1 /* Copyright (C) 1999 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <errno.h>
  20 #include <sys/resource.h>
  21
  22 #include <sysdep.h>
  23 #include <sys/syscall.h>
  24
  25 #include "kernel-features.h"
  26
  27 extern int __syscall_ugetrlimit __P ((unsigned int resource,
  28                                       struct rlimit *rlimits));
  29 extern int __syscall_getrlimit __P ((unsigned int resource,
  30                                      struct rlimit *rlimits));
  31
  32 /* Linux 2.3.25 introduced a new system call since the types used for
  33    the limits are now unsigned.  */
  34 #if defined __NR_ugetrlimit && !defined __ASSUME_NEW_GETRLIMIT_SYSCALL
  35 int __have_no_new_getrlimit;
  36 #endif
  37
  38 int
  39 __new_getrlimit (enum __rlimit_resource resource, struct rlimit *rlimits)
  40 {
  41 #ifdef __ASSUME_NEW_GETRLIMIT_SYSCALL
  42   return INLINE_SYSCALL (ugetrlimit, 2, resource, rlimits);
  43 #else
  44   int result;
  45
  46 # ifdef __NR_ugetrlimit
  47   if (__have_no_new_getrlimit <= 0)
  48     {
  49       result = INLINE_SYSCALL (ugetrlimit, 2, resource, rlimits);
  50
  51       /* If the system call is available remember this fact and return.  */
  52       if (result != -1 || errno != ENOSYS)
  53         {
  54           __have_no_new_getrlimit = -1;
  55           return result;
  56         }
  57
  58       /* Remember that the system call is not available.  */
  59       __have_no_new_getrlimit = 1;
  60     }
  61 # endif
  62
  63   /* Fall back to the old system call.  */
  64   result = INLINE_SYSCALL (getrlimit, 2, resource, rlimits);
  65
  66   if (result == -1)
  67     return result;
  68
  69   /* We might have to correct the limits values.  Since the old values
  70      were signed the infinity value is too small.  */
  71   if (rlimits->rlim_cur == RLIM_INFINITY >> 1)
  72     rlimits->rlim_cur = RLIM_INFINITY;
  73   if (rlimits->rlim_max == RLIM_INFINITY >> 1)
  74     rlimits->rlim_max = RLIM_INFINITY;
  75
  76   return result;
  77 #endif
  78 }
  79
  80 #if defined PIC && DO_VERSIONING
  81 default_symbol_version (__new_getrlimit, __getrlimit, GLIBC_2.1.3);
  82 strong_alias (__new_getrlimit, _new_getrlimit);
  83 default_symbol_version (_new_getrlimit, getrlimit, GLIBC_2.1.3);
  84 #else
  85 weak_alias (__new_getrlimit, __getrlimit);
  86 weak_alias (__new_getrlimit, getrlimit);
  87 #endif