tests/df/no-mtab-status.sh

   1 #!/bin/sh
   2 # Test df's behaviour when the mount list cannot be read.
   3 # This test is skipped on systems that lack LD_PRELOAD support; that's fine.
   4
   5 # Copyright (C) 2012-2017 Free Software Foundation, Inc.
   6
   7 # This program is free software: you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation, either version 3 of the License, or
  10 # (at your option) any later version.
  11
  12 # This program is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16
  17 # You should have received a copy of the GNU General Public License
  18 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19
  20 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  21 print_ver_ df
  22 require_gcc_shared_
  23
  24 # Protect against inaccessible remote mounts etc.
  25 timeout 10 df || skip_ "df fails"
  26
  27 grep '^#define HAVE_MNTENT_H 1' $CONFIG_HEADER > /dev/null \
  28       || skip_ "no mntent.h available to confirm the interface"
  29
  30 grep '^#define HAVE_GETMNTENT 1' $CONFIG_HEADER > /dev/null \
  31       || skip_ "getmntent is not used on this system"
  32
  33 # Simulate "mtab" failure.
  34 cat > k.c <<EOF || framework_failure_
  35 #define _GNU_SOURCE
  36 #include <stdio.h>
  37 #include <errno.h>
  38 #include <mntent.h>
  39 #include <string.h>
  40 #include <dlfcn.h>
  41
  42 #define STREQ(a, b) (strcmp (a, b) == 0)
  43
  44 FILE* fopen(const char *path, const char *mode)
  45 {
  46   static FILE* (*fopen_func)(char const *, char const *);
  47
  48   /* get reference to original (libc provided) fopen */
  49   if (!fopen_func)
  50     {
  51       fopen_func = (FILE*(*)(char const *, char const *))
  52                    dlsym(RTLD_NEXT, "fopen");
  53       if (!fopen_func)
  54         {
  55           fprintf (stderr, "Failed to find fopen()\n");
  56           errno = ESRCH;
  57           return NULL;
  58         }
  59     }
  60
  61   /* Returning ENOENT here will get read_file_system_list()
  62      to fall back to using getmntent() below.  */
  63   if (STREQ (path, "/proc/self/mountinfo"))
  64     {
  65       errno = ENOENT;
  66       return NULL;
  67     }
  68   else
  69     return fopen_func(path, mode);
  70 }
  71
  72 struct mntent *getmntent (FILE *fp)
  73 {
  74   /* Prove that LD_PRELOAD works. */
  75   static int done = 0;
  76   if (!done)
  77     {
  78       fclose (fopen ("x", "w"));
  79       ++done;
  80     }
  81   /* Now simulate the failure. */
  82   errno = ENOENT;
  83   return NULL;
  84 }
  85 EOF
  86
  87 # Then compile/link it:
  88 gcc_shared_ k.c k.so \
  89   || framework_failure_ 'failed to build shared library'
  90
  91 cleanup_() { unset LD_PRELOAD; }
  92
  93 export LD_PRELOAD=$LD_PRELOAD:./k.so
  94
  95 # Test if LD_PRELOAD works:
  96 df 2>/dev/null
  97 test -f x || skip_ "internal test failure: maybe LD_PRELOAD doesn't work?"
  98
  99 # These tests are supposed to succeed:
 100 df '.' || fail=1
 101 df -i '.' || fail=1
 102 df -T '.' || fail=1
 103 df -Ti '.' || fail=1
 104 df --total '.' || fail=1
 105
 106 # These tests are supposed to fail:
 107 returns_ 1 df || fail=1
 108 returns_ 1 df -i || fail=1
 109 returns_ 1 df -T || fail=1
 110 returns_ 1 df -Ti || fail=1
 111 returns_ 1 df --total || fail=1
 112
 113 returns_ 1 df -a || fail=1
 114 returns_ 1 df -a '.' || fail=1
 115
 116 returns_ 1 df -l || fail=1
 117 returns_ 1 df -l '.' || fail=1
 118
 119 returns_ 1 df -t hello || fail=1
 120 returns_ 1 df -t hello '.' || fail=1
 121
 122 returns_ 1 df -x hello || fail=1
 123 returns_ 1 df -x hello '.' || fail=1
 124
 125 Exit $fail