sysdeps/unix/sysv/linux/ulimit.c

   1 /* Copyright (C) 1991,92,1994-1998,2000,2001,2008
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <errno.h>
  21 #include <stdarg.h>
  22 #include <sysdep.h>
  23 #include <ulimit.h>
  24 #include <unistd.h>
  25 #include <sys/resource.h>
  26
  27 /* Function depends on CMD:
  28    1 = Return the limit on the size of a file, in units of 512 bytes.
  29    2 = Set the limit on the size of a file to NEWLIMIT.  Only the
  30        super-user can increase the limit.
  31    3 = illegal due to shared libraries; normally is
  32        (Return the maximum possible address of the data segment.)
  33    4 = Return the maximum number of files that the calling process
  34        can open.
  35    Returns -1 on errors.  */
  36 long int
  37 __ulimit (int cmd, ...)
  38 {
  39   struct rlimit limit;
  40   va_list va;
  41   long int result = -1;
  42
  43   va_start (va, cmd);
  44
  45   switch (cmd)
  46     {
  47     case UL_GETFSIZE:
  48       /* Get limit on file size.  */
  49       if (__getrlimit (RLIMIT_FSIZE, &limit) == 0)
  50         /* Convert from bytes to 512 byte units.  */
  51         result =  (limit.rlim_cur == RLIM_INFINITY
  52                    ? LONG_MAX : limit.rlim_cur / 512);
  53       break;
  54
  55     case UL_SETFSIZE:
  56       /* Set limit on file size.  */
  57       {
  58         long int newlimit = va_arg (va, long int);
  59         long int newlen;
  60
  61         if ((rlim_t) newlimit > RLIM_INFINITY / 512)
  62           {
  63             limit.rlim_cur = RLIM_INFINITY;
  64             limit.rlim_max = RLIM_INFINITY;
  65             newlen = LONG_MAX;
  66           }
  67         else
  68           {
  69             limit.rlim_cur = newlimit * 512;
  70             limit.rlim_max = newlimit * 512;
  71             newlen = newlimit;
  72           }
  73
  74         result = __setrlimit (RLIMIT_FSIZE, &limit);
  75         if (result != -1)
  76           result = newlen;
  77       }
  78       break;
  79
  80     case __UL_GETOPENMAX:
  81       result = __sysconf (_SC_OPEN_MAX);
  82       break;
  83
  84     default:
  85       __set_errno (EINVAL);
  86     }
  87
  88   va_end (va);
  89
  90   return result;
  91 }
  92
  93 weak_alias (__ulimit, ulimit);