tests/tail/inotify-dir-recreate.sh

   1 #!/bin/sh
   2 # Makes sure, inotify will switch to polling mode if directory
   3 # of the watched file was removed and recreated.
   4 # (...instead of getting stuck forever)
   5
   6 # Copyright (C) 2017-2024 Free Software Foundation, Inc.
   7
   8 # This program is free software: you can redistribute it and/or modify
   9 # it under the terms of the GNU General Public License as published by
  10 # the Free Software Foundation, either version 3 of the License, or
  11 # (at your option) any later version.
  12
  13 # This program is distributed in the hope that it will be useful,
  14 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 # GNU General Public License for more details.
  17
  18 # You should have received a copy of the GNU General Public License
  19 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  20
  21 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  22 print_ver_ tail
  23
  24 grep '^#define HAVE_INOTIFY 1' "$CONFIG_HEADER" >/dev/null && is_local_dir_ . \
  25   || skip_ 'inotify is not supported'
  26
  27 # Terminate any background tail process
  28 cleanup_() { kill $pid 2>/dev/null && wait $pid; }
  29
  30 cleanup_fail_ ()
  31 {
  32   warn_ $1
  33   cleanup_
  34   fail=1
  35 }
  36
  37 # $check_re - string to be found
  38 # $check_f - file to be searched
  39 check_tail_output_ ()
  40 {
  41   local delay="$1"
  42   grep $check_re $check_f > /dev/null ||
  43     { sleep $delay ; return 1; }
  44 }
  45
  46 grep_timeout_ ()
  47 {
  48   check_re="$1"
  49   check_f="$2"
  50   retry_delay_ check_tail_output_ .1 5
  51 }
  52
  53 # Prepare the file to be watched
  54 mkdir dir && echo 'inotify' > dir/file || framework_failure_
  55
  56 #tail must print content of the file to stdout, verify
  57 timeout 60 tail --pid=$$ -F dir/file >out 2>&1 & pid=$!
  58 grep_timeout_ 'inotify' 'out' ||
  59 { cleanup_fail_ 'file to be tailed does not exist'; }
  60
  61 inotify_failed_re='inotify (resources exhausted|cannot be used)'
  62 grep -E "$inotify_failed_re" out &&
  63   skip_ "inotify can't be used"
  64
  65 # Remove the directory, should get the message about the deletion
  66 rm -r dir || framework_failure_
  67 grep_timeout_ 'polling' 'out' ||
  68 { cleanup_fail_ 'tail did not switch to polling mode'; }
  69
  70 # Recreate the dir, must get a message about recreation
  71 mkdir dir && touch dir/file || framework_failure_
  72 grep_timeout_ 'appeared' 'out' ||
  73 { cleanup_fail_ 'previously removed file did not appear'; }
  74
  75 cleanup_
  76
  77 # Expected result for the whole process
  78 cat <<\EOF > exp || framework_failure_
  79 inotify
  80 tail: 'dir/file' has become inaccessible: No such file or directory
  81 tail: directory containing watched file was removed
  82 tail: inotify cannot be used, reverting to polling
  83 tail: 'dir/file' has appeared;  following new file
  84 EOF
  85
  86 compare exp out || fail=1
  87
  88 Exit $fail