lib/caputils.c

   1 /*
   2  * This program is free software; you can redistribute it and/or modify it
   3  * under the terms of the GNU General Public License as published by the
   4  * Free Software Foundation; either version 2, or (at your option) any
   5  * later version.
   6  *
   7  * This program is distributed in the hope that it will be useful, but
   8  * WITHOUT ANY WARRANTY; without even the implied warranty of
   9  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  10  * General Public License for more details.
  11  *
  12  * You should have received a copy of the GNU General Public License along
  13  * with this program; if not, write to the Free Software Foundation, Inc.,
  14  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  15  */
  16
  17 #include <stdio.h>
  18
  19 #include "caputils.h"
  20 #include "pathnames.h"
  21
  22 int cap_last_cap(void)
  23 {
  24         /* CAP_LAST_CAP is untrustworthy. */
  25         static int ret = -1;
  26         int matched;
  27         FILE *f;
  28
  29         if (ret != -1)
  30                 return ret;
  31
  32         f = fopen(_PATH_PROC_CAPLASTCAP, "r");
  33         if (!f) {
  34                 ret = CAP_LAST_CAP;     /* guess */
  35                 return ret;
  36         }
  37
  38         matched = fscanf(f, "%d", &ret);
  39         fclose(f);
  40
  41         if (matched != 1)
  42                 ret = CAP_LAST_CAP;     /* guess */
  43
  44         return ret;
  45 }