tests/df/skip-duplicates.sh

   1 #!/bin/sh
   2 # Test df's behavior when the mount list contains duplicate entries.
   3 # This test is skipped on systems that lack LD_PRELOAD support; that's fine.
   4
   5 # Copyright (C) 2012-2015 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 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  21 print_ver_ df
  22 require_gcc_shared_
  23
  24 # We use --local here so as to not activate
  25 # potentially very many remote mounts.
  26 df --local || skip_ 'df fails'
  27
  28 export CU_NONROOT_FS=$(df --local --output=target 2>&1 | grep /. | head -n1)
  29 export CU_REMOTE_FS=$(df --local --output=target 2>&1 | grep /. |
  30                       tail -n+2 | head -n1)
  31
  32 unique_entries=1
  33 test -z "$CU_NONROOT_FS" || unique_entries=$(expr $unique_entries + 1)
  34 test -z "$CU_REMOTE_FS" || unique_entries=$(expr $unique_entries + 2)
  35
  36 grep '^#define HAVE_MNTENT_H 1' $CONFIG_HEADER > /dev/null \
  37       || skip_ "no mntent.h available to confirm the interface"
  38
  39 grep '^#define HAVE_GETMNTENT 1' $CONFIG_HEADER > /dev/null \
  40       || skip_ "getmntent is not used on this system"
  41
  42 # Simulate an mtab file to test various cases.
  43 cat > k.c <<EOF || framework_failure_
  44 #define _GNU_SOURCE
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <errno.h>
  48 #include <mntent.h>
  49 #include <string.h>
  50 #include <dlfcn.h>
  51
  52 #define STREQ(a, b) (strcmp (a, b) == 0)
  53
  54 FILE* fopen(const char *path, const char *mode)
  55 {
  56   static FILE* (*fopen_func)(char const *, char const *);
  57
  58   /* get reference to original (libc provided) fopen */
  59   if (!fopen_func)
  60     {
  61       fopen_func = (FILE*(*)(char const *, char const *))
  62                    dlsym(RTLD_NEXT, "fopen");
  63       if (!fopen_func)
  64         {
  65           fprintf (stderr, "Failed to find fopen()\n");
  66           errno = ESRCH;
  67           return NULL;
  68         }
  69     }
  70
  71   /* Returning ENOENT here will get read_file_system_list()
  72      to fall back to using getmntent() below.  */
  73   if (STREQ (path, "/proc/self/mountinfo"))
  74     {
  75       errno = ENOENT;
  76       return NULL;
  77     }
  78   else
  79     return fopen_func(path, mode);
  80 }
  81
  82 #define STREQ(a, b) (strcmp (a, b) == 0)
  83
  84 struct mntent *getmntent (FILE *fp)
  85 {
  86   static char *nonroot_fs;
  87   static char *remote_fs;
  88   static int done;
  89
  90   /* Prove that LD_PRELOAD works. */
  91   if (!done)
  92     {
  93       fclose (fopen ("x", "w"));
  94       ++done;
  95     }
  96
  97   static struct mntent mntents[] = {
  98     {.mnt_fsname="/short",  .mnt_dir="/invalid/mount/dir",       .mnt_opts=""},
  99     {.mnt_fsname="fsname",  .mnt_dir="/",                        .mnt_opts=""},
 100     {.mnt_fsname="/fsname", .mnt_dir="/.",                       .mnt_opts=""},
 101     {.mnt_fsname="/fsname", .mnt_dir="/",                        .mnt_opts=""},
 102     {.mnt_fsname="virtfs",  .mnt_dir="/NONROOT", .mnt_type="t1", .mnt_opts=""},
 103     {.mnt_fsname="virtfs2", .mnt_dir="/NONROOT", .mnt_type="t2", .mnt_opts=""},
 104     {.mnt_fsname="netns",   .mnt_dir="net:[1234567]",            .mnt_opts=""},
 105     {.mnt_fsname="rem:ote1",.mnt_dir="/REMOTE",                  .mnt_opts=""},
 106     {.mnt_fsname="rem:ote1",.mnt_dir="/REMOTE",                  .mnt_opts=""},
 107     {.mnt_fsname="rem:ote2",.mnt_dir="/REMOTE",                  .mnt_opts=""},
 108   };
 109
 110   if (done == 1)
 111     {
 112       nonroot_fs = getenv ("CU_NONROOT_FS");
 113       if (!nonroot_fs || !*nonroot_fs)
 114         nonroot_fs = "/"; /* merge into / entries.  */
 115
 116       remote_fs = getenv ("CU_REMOTE_FS");
 117     }
 118
 119   if (done == 1 && !getenv ("CU_TEST_DUPE_INVALID"))
 120     done++;  /* skip the first entry.  */
 121
 122   while (done++ <= 10)
 123     {
 124       if (!mntents[done-2].mnt_type)
 125         mntents[done-2].mnt_type = "-";
 126       if (!mntents[done-2].mnt_opts)
 127         mntents[done-2].mnt_opts = "-";
 128       if (STREQ (mntents[done-2].mnt_dir, "/NONROOT"))
 129         mntents[done-2].mnt_dir = nonroot_fs;
 130       if (STREQ (mntents[done-2].mnt_dir, "/REMOTE"))
 131         {
 132           if (!remote_fs || !*remote_fs)
 133             continue;
 134           else
 135             mntents[done-2].mnt_dir = remote_fs;
 136         }
 137       return &mntents[done-2];
 138     }
 139
 140   return NULL;
 141 }
 142 EOF
 143
 144 # Then compile/link it:
 145 gcc_shared_ k.c k.so \
 146   || framework_failure_ 'failed to build shared library'
 147
 148 # Test if LD_PRELOAD works:
 149 LD_PRELOAD=$LD_PRELOAD:./k.so df
 150 test -f x || skip_ "internal test failure: maybe LD_PRELOAD doesn't work?"
 151
 152 # The fake mtab file should only contain entries
 153 # having the same device number; thus the output should
 154 # consist of a header and unique entries.
 155 LD_PRELOAD=$LD_PRELOAD:./k.so df -T >out || fail=1
 156 test $(wc -l <out) -eq $(expr 1 + $unique_entries) || { fail=1; cat out; }
 157
 158 # With --total we should suppress the duplicate but separate remote file system
 159 LD_PRELOAD=$LD_PRELOAD:./k.so df --total >out || fail=1
 160 test "$CU_REMOTE_FS" && elide_remote=1 || elide_remote=0
 161 test $(wc -l <out) -eq $(expr 2 + $unique_entries - $elide_remote) ||
 162   { fail=1; cat out; }
 163
 164 # Ensure we don't fail when unable to stat (currently) unavailable entries
 165 LD_PRELOAD=$LD_PRELOAD:./k.so CU_TEST_DUPE_INVALID=1 df -T >out || fail=1
 166 test $(wc -l <out) -eq $(expr 1 + $unique_entries) || { fail=1; cat out; }
 167
 168 # df should also prefer "/fsname" over "fsname"
 169 if test "$unique_entries" = 2; then
 170   test $(grep -c '/fsname' <out) -eq 1 || { fail=1; cat out; }
 171   # ... and "/fsname" with '/' as Mounted on over '/.'
 172   test $(grep -cF '/.' <out) -eq 0 || { fail=1; cat out; }
 173 fi
 174
 175 # df should use the last seen devname (mnt_fsname) and devtype (mnt_type)
 176 test $(grep -c 'virtfs2.*t2' <out) -eq 1 || { fail=1; cat out; }
 177
 178 # Ensure that filtering duplicates does not affect -a processing.
 179 LD_PRELOAD=$LD_PRELOAD:./k.so df -a >out || fail=1
 180 total_fs=6; test "$CU_REMOTE_FS" && total_fs=$(expr $total_fs + 3)
 181 test $(wc -l <out) -eq $total_fs || { fail=1; cat out; }
 182 # Ensure placeholder "-" values used for the eclipsed "virtfs"
 183 test $(grep -c 'virtfs *-' <out) -eq 1 || { fail=1; cat out; }
 184
 185 # Ensure that filtering duplicates does not affect
 186 # argument processing (now without the fake getmntent()).
 187 df '.' '.' >out || fail=1
 188 test $(wc -l <out) -eq 3 || { fail=1; cat out; }
 189
 190 Exit $fail