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) 2012-2017 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 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  21 print_ver_ df
  22 require_gcc_shared_
  23
  24 # We use --local here so as to not activate
  25 # potentially very many remote mounts.
  26 df --local --output=target >LOCAL_FS || skip_ 'df fails'
  27 grep '^/$' LOCAL_FS || skip_ 'no root file system found'
  28
  29 # Get real targets to substitute for /NONROOT and /REMOTE below.
  30 export CU_NONROOT_FS=$(grep /. LOCAL_FS | head -n1)
  31 export CU_REMOTE_FS=$(grep /. LOCAL_FS | tail -n+2 | head -n1)
  32
  33 unique_entries=1
  34 test -z "$CU_NONROOT_FS" || unique_entries=$(expr $unique_entries + 1)
  35 test -z "$CU_REMOTE_FS" || unique_entries=$(expr $unique_entries + 2)
  36
  37 grep '^#define HAVE_MNTENT_H 1' $CONFIG_HEADER > /dev/null \
  38       || skip_ "no mntent.h available to confirm the interface"
  39
  40 grep '^#define HAVE_GETMNTENT 1' $CONFIG_HEADER > /dev/null \
  41       || skip_ "getmntent is not used on this system"
  42
  43 # Simulate an mtab file to test various cases.
  44 cat > k.c <<EOF || framework_failure_
  45 #define _GNU_SOURCE
  46 #include <stdio.h>
  47 #include <stdlib.h>
  48 #include <errno.h>
  49 #include <mntent.h>
  50 #include <string.h>
  51 #include <dlfcn.h>
  52
  53 #define STREQ(a, b) (strcmp (a, b) == 0)
  54
  55 FILE* fopen(const char *path, const char *mode)
  56 {
  57   static FILE* (*fopen_func)(char const *, char const *);
  58
  59   /* get reference to original (libc provided) fopen */
  60   if (!fopen_func)
  61     {
  62       fopen_func = (FILE*(*)(char const *, char const *))
  63                    dlsym(RTLD_NEXT, "fopen");
  64       if (!fopen_func)
  65         {
  66           fprintf (stderr, "Failed to find fopen()\n");
  67           errno = ESRCH;
  68           return NULL;
  69         }
  70     }
  71
  72   /* Returning ENOENT here will get read_file_system_list()
  73      to fall back to using getmntent() below.  */
  74   if (STREQ (path, "/proc/self/mountinfo"))
  75     {
  76       errno = ENOENT;
  77       return NULL;
  78     }
  79   else
  80     return fopen_func(path, mode);
  81 }
  82
  83 #define STREQ(a, b) (strcmp (a, b) == 0)
  84
  85 struct mntent *getmntent (FILE *fp)
  86 {
  87   static char *nonroot_fs;
  88   static char *remote_fs;
  89   static int done;
  90
  91   /* Prove that LD_PRELOAD works. */
  92   if (!done)
  93     {
  94       fclose (fopen ("x", "w"));
  95       ++done;
  96     }
  97
  98   static struct mntent mntents[] = {
  99     {.mnt_fsname="/short",  .mnt_dir="/invalid/mount/dir",       .mnt_opts=""},
 100     {.mnt_fsname="fsname",  .mnt_dir="/",                        .mnt_opts=""},
 101     {.mnt_fsname="/fsname", .mnt_dir="/.",                       .mnt_opts=""},
 102     {.mnt_fsname="/fsname", .mnt_dir="/",                        .mnt_opts=""},
 103     {.mnt_fsname="virtfs",  .mnt_dir="/NONROOT", .mnt_type="t1", .mnt_opts=""},
 104     {.mnt_fsname="virtfs2", .mnt_dir="/NONROOT", .mnt_type="t2", .mnt_opts=""},
 105     {.mnt_fsname="netns",   .mnt_dir="net:[1234567]",            .mnt_opts=""},
 106     {.mnt_fsname="rem:ote1",.mnt_dir="/REMOTE",                  .mnt_opts=""},
 107     {.mnt_fsname="rem:ote1",.mnt_dir="/REMOTE",                  .mnt_opts=""},
 108     {.mnt_fsname="rem:ote2",.mnt_dir="/REMOTE",                  .mnt_opts=""},
 109   };
 110
 111   if (done == 1)
 112     {
 113       nonroot_fs = getenv ("CU_NONROOT_FS");
 114       if (!nonroot_fs || !*nonroot_fs)
 115         nonroot_fs = "/"; /* merge into / entries.  */
 116
 117       remote_fs = getenv ("CU_REMOTE_FS");
 118     }
 119
 120   if (done == 1 && !getenv ("CU_TEST_DUPE_INVALID"))
 121     done++;  /* skip the first entry.  */
 122
 123   while (done++ <= 10)
 124     {
 125       if (!mntents[done-2].mnt_type)
 126         mntents[done-2].mnt_type = "-";
 127       if (!mntents[done-2].mnt_opts)
 128         mntents[done-2].mnt_opts = "-";
 129       if (STREQ (mntents[done-2].mnt_dir, "/NONROOT"))
 130         mntents[done-2].mnt_dir = nonroot_fs;
 131       if (STREQ (mntents[done-2].mnt_dir, "/REMOTE"))
 132         {
 133           if (!remote_fs || !*remote_fs)
 134             continue;
 135           else
 136             mntents[done-2].mnt_dir = remote_fs;
 137         }
 138       return &mntents[done-2];
 139     }
 140
 141   return NULL;
 142 }
 143 EOF
 144
 145 # Then compile/link it:
 146 gcc_shared_ k.c k.so \
 147   || framework_failure_ 'failed to build shared library'
 148
 149 # Test if LD_PRELOAD works:
 150 LD_PRELOAD=$LD_PRELOAD:./k.so df
 151 test -f x || skip_ "internal test failure: maybe LD_PRELOAD doesn't work?"
 152
 153 # The fake mtab file should only contain entries
 154 # having the same device number; thus the output should
 155 # consist of a header and unique entries.
 156 LD_PRELOAD=$LD_PRELOAD:./k.so df -T >out || fail=1
 157 test $(wc -l <out) -eq $(expr 1 + $unique_entries) || { fail=1; cat out; }
 158
 159 # With --total we should suppress the duplicate but separate remote file system
 160 LD_PRELOAD=$LD_PRELOAD:./k.so df --total >out || fail=1
 161 test "$CU_REMOTE_FS" && elide_remote=1 || elide_remote=0
 162 test $(wc -l <out) -eq $(expr 2 + $unique_entries - $elide_remote) ||
 163   { fail=1; cat out; }
 164
 165 # Ensure we don't fail when unable to stat (currently) unavailable entries
 166 LD_PRELOAD=$LD_PRELOAD:./k.so CU_TEST_DUPE_INVALID=1 df -T >out || fail=1
 167 test $(wc -l <out) -eq $(expr 1 + $unique_entries) || { fail=1; cat out; }
 168
 169 # df should also prefer "/fsname" over "fsname"
 170 if test "$unique_entries" = 2; then
 171   test $(grep -c '/fsname' <out) -eq 1 || { fail=1; cat out; }
 172   # ... and "/fsname" with '/' as Mounted on over '/.'
 173   test $(grep -cF '/.' <out) -eq 0 || { fail=1; cat out; }
 174 fi
 175
 176 # df should use the last seen devname (mnt_fsname) and devtype (mnt_type)
 177 test $(grep -c 'virtfs2.*t2' <out) -eq 1 || { fail=1; cat out; }
 178
 179 # Ensure that filtering duplicates does not affect -a processing.
 180 LD_PRELOAD=$LD_PRELOAD:./k.so df -a >out || fail=1
 181 total_fs=6; test "$CU_REMOTE_FS" && total_fs=$(expr $total_fs + 3)
 182 test $(wc -l <out) -eq $total_fs || { fail=1; cat out; }
 183 # Ensure placeholder "-" values used for the eclipsed "virtfs"
 184 test $(grep -c 'virtfs *-' <out) -eq 1 || { fail=1; cat out; }
 185
 186 # Ensure that filtering duplicates does not affect
 187 # argument processing (now without the fake getmntent()).
 188 df '.' '.' >out || fail=1
 189 test $(wc -l <out) -eq 3 || { fail=1; cat out; }
 190
 191 Exit $fail