tests/tail/inotify-rotate.sh

   1 #!/bin/sh
   2 # ensure that tail -F handles rotation
   3
   4 # Copyright (C) 2009-2024 Free Software Foundation, Inc.
   5
   6 # This program is free software: you can redistribute it and/or modify
   7 # it under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation, either version 3 of the License, or
   9 # (at your option) any later version.
  10
  11 # This program is distributed in the hope that it will be useful,
  12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 # GNU General Public License for more details.
  15
  16 # You should have received a copy of the GNU General Public License
  17 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
  18
  19 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
  20 print_ver_ tail
  21
  22 grep '^#define HAVE_INOTIFY 1' "$CONFIG_HEADER" >/dev/null \
  23   || expensive_
  24
  25 check_tail_output()
  26 {
  27   local delay="$1"
  28   grep "$tail_re" out > /dev/null ||
  29     { sleep $delay; return 1; }
  30 }
  31
  32 # Wait up to 25.5 seconds for grep REGEXP 'out' to succeed.
  33 grep_timeout() { tail_re="$1" retry_delay_ check_tail_output .1 8; }
  34
  35 # Terminate any background tail process
  36 cleanup_() { kill $pid 2>/dev/null && wait $pid; }
  37
  38 cleanup_fail()
  39 {
  40   cat out
  41   warn_ $1
  42   cleanup_
  43   fail=1
  44 }
  45
  46 # Speedup the non inotify case
  47 fastpoll='-s.1 --max-unchanged-stats=1'
  48
  49 # Perform at least this many iterations, because on multi-core systems
  50 # the offending sequence of events can be surprisingly uncommon.
  51 # See: https://lists.gnu.org/r/bug-coreutils/2009-11/msg00213.html
  52 for i in $(seq 50); do
  53     echo $i
  54     rm -f k x out
  55
  56     # Normally less than a second is required here, but with heavy load
  57     # and a lot of file system activity, even 20 seconds is insufficient, which
  58     # leads to this timeout killing tail before the "ok" is written below.
  59     >k && >x || framework_failure_ failed to initialize files
  60     timeout 60 tail $fastpoll -F k > out 2>&1 & pid=$!
  61
  62     echo 'tailed' > k;
  63     # wait for 'tailed' to appear in out
  64     grep_timeout 'tailed' || { cleanup_fail 'failed to find "tailed"'; break; }
  65
  66     mv x k
  67     # wait for tail to detect the rename
  68     grep_timeout 'tail:' || { cleanup_fail 'failed to detect rename'; break; }
  69
  70     echo ok >> k
  71     # wait for "ok" to appear in 'out'
  72     grep_timeout 'ok' || { cleanup_fail 'failed to detect echoed ok'; break; }
  73
  74     cleanup_
  75 done
  76
  77 Exit $fail