posix/getconf.c

   1 /* Copyright (C) 1991, 1992, 1995, 1996 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
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <unistd.h>
  21 #include <errno.h>
  22 #include <string.h>
  23 #include <stdlib.h>
  24 #include <stdio.h>
  25
  26 struct conf
  27   {
  28     CONST char *name;
  29     CONST int call_name;
  30     CONST enum { SYSCONF, CONFSTR, PATHCONF } call;
  31   };
  32
  33 static struct conf vars[] =
  34   {
  35     { "LINK_MAX", _PC_LINK_MAX, PATHCONF },
  36     { "MAX_CANON", _PC_MAX_CANON, PATHCONF },
  37     { "MAX_INPUT", _PC_MAX_INPUT, PATHCONF },
  38     { "NAME_MAX", _PC_NAME_MAX, PATHCONF },
  39     { "PATH_MAX", _PC_PATH_MAX, PATHCONF },
  40     { "PIPE_BUF", _PC_PIPE_BUF, PATHCONF },
  41     { "_POSIX_CHOWN_RESTRICTED", _PC_CHOWN_RESTRICTED, PATHCONF },
  42     { "_POSIX_NO_TRUNC", _PC_NO_TRUNC, PATHCONF },
  43     { "_POSIX_VDISABLE", _PC_VDISABLE, PATHCONF },
  44     { "_POSIX_SYNC_IO", _PC_SYNC_IO, PATHCONF },
  45     { "_POSIX_ASYNC_IO", _PC_ASYNC_IO, PATHCONF },
  46     { "_POSIX_PRIO_IO", _PC_PRIO_IO, PATHCONF },
  47
  48     { "ARG_MAX", _SC_ARG_MAX, SYSCONF },
  49     { "CHILD_MAX", _SC_CHILD_MAX, SYSCONF },
  50     { "CLK_TCK", _SC_CLK_TCK, SYSCONF },
  51     { "NGROUPS_MAX", _SC_NGROUPS_MAX, SYSCONF },
  52     { "OPEN_MAX", _SC_OPEN_MAX, SYSCONF },
  53     { "_POSIX_JOB_CONTROL", _SC_JOB_CONTROL, SYSCONF },
  54     { "_POSIX_SAVED_IDS", _SC_SAVED_IDS, SYSCONF },
  55     { "_POSIX_REALTIME_SIGNALS", _SC_REALTIME_SIGNALS, SYSCONF },
  56     { "_POSIX_PRIORITY_SCHEDULING", _SC_PRIORITY_SCHEDULING, SYSCONF },
  57     { "_POSIX_TIMERS", _SC_TIMERS, SYSCONF },
  58     { "_POSIX_ASYNCHRONOUS_IO", _SC_ASYNCHRONOUS_IO, SYSCONF },
  59     { "_POSIX_PRIORITIZED_IO", _SC_PRIORITIZED_IO, SYSCONF },
  60     { "_POSIX_SYNCHRONIZED_IO", _SC_SYNCHRONIZED_IO, SYSCONF },
  61     { "_POSIX_FSYNC", _SC_FSYNC, SYSCONF },
  62     { "_POSIX_MAPPED_FILES", _SC_MAPPED_FILES, SYSCONF },
  63     { "_POSIX_MEMLOCK", _SC_MEMLOCK, SYSCONF },
  64     { "_POSIX_MEMLOCK_RANGE", _SC_MEMLOCK_RANGE, SYSCONF },
  65     { "_POSIX_MEMORY_PROTECTION", _SC_MEMORY_PROTECTION, SYSCONF },
  66     { "_POSIX_MESSAGE_PASSING", _SC_MESSAGE_PASSING, SYSCONF },
  67     { "_POSIX_SEMAPHORES", _SC_SEMAPHORES, SYSCONF },
  68     { "_POSIX_SHARED_MEMORY_OBJECTS", _SC_SHARED_MEMORY_OBJECTS, SYSCONF },
  69     { "_POSIX_VERSION", _SC_VERSION, SYSCONF },
  70
  71     { "PATH", _CS_PATH, CONFSTR },
  72
  73     { NULL, 0, SYSCONF }
  74   };
  75
  76 static CONST char *program;
  77
  78 static void
  79 DEFUN_VOID(usage)
  80 {
  81   fprintf (stderr, _("Usage: %s variable_name [pathname]\n"), program);
  82   exit (2);
  83 }
  84
  85 int
  86 DEFUN(main, (argc, argv), int argc AND char **argv)
  87 {
  88   register CONST struct conf *c;
  89
  90   program = strrchr (argv[0], '/');
  91   if (program == NULL)
  92     program = argv[0];
  93   else
  94     ++program;
  95
  96   if (argc < 2 || argc > 3)
  97     usage ();
  98
  99   for (c = vars; c->name != NULL; ++c)
 100     if (!strcmp (c->name, argv[1]))
 101       {
 102         long int value;
 103         size_t clen;
 104         char *cvalue;
 105         switch (c->call)
 106           {
 107           case PATHCONF:
 108             if (argc < 3)
 109               usage ();
 110             value = pathconf (argv[2], c->call_name);
 111             if (value == -1)
 112               {
 113                 fprintf (stderr, "%s: pathconf: %s: %s\n",
 114                          program, argv[2], strerror (errno));
 115                 exit (3);
 116               }
 117             printf ("%ld\n", value);
 118             exit (0);
 119
 120           case SYSCONF:
 121             if (argc > 2)
 122               usage ();
 123             value = sysconf (c->call_name);
 124             printf ("%ld\n", value);
 125             exit (0);
 126
 127           case CONFSTR:
 128             if (argc > 2)
 129               usage ();
 130             clen = confstr (c->call_name, (char *) NULL, 0);
 131             cvalue = (char *) malloc (clen);
 132             if (cvalue == NULL)
 133               {
 134                 fprintf (stderr, "%s: malloc: %s\n",
 135                          program, strerror (errno));
 136                 exit (3);
 137               }
 138             if (confstr (c->call_name, cvalue, clen) != clen)
 139               {
 140                 fprintf (stderr, "%s: confstr: %s\n",
 141                          program, strerror (errno));
 142                 exit (3);
 143               }
 144             printf ("%.*s\n", (int) clen, cvalue);
 145             exit (0);
 146           }
 147       }
 148
 149   fprintf (stderr, _("%s: Unrecognized variable `%s'\n"), program, argv[1]);
 150   exit (2);
 151 }