tests/tail-2/pipe-f.sh

   1 #!/bin/sh
   2 # ensure that tail -f doesn't hang in various cases
   3
   4 # Copyright (C) 2009-2023 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 test head
  21 trap_sigpipe_or_skip_
  22
  23 # Speedup the non inotify case
  24 fastpoll='-s.1 --max-unchanged-stats=1'
  25
  26 for mode in '' '---disable-inotify'; do
  27 # Ensure :|tail -f doesn't hang, per POSIX
  28 echo oo > exp || framework_failure_
  29 echo foo | timeout 10 tail -f $mode $fastpoll -c3 > out || fail=1
  30 compare exp out || fail=1
  31 cat <<\EOF > exp || framework_failure_
  32 ==> standard input <==
  33 ar
  34 EOF
  35 echo bar | returns_ 1 \
  36  timeout 10 tail -f $mode $fastpoll -c3 - missing > out || fail=1
  37 compare exp out || fail=1
  38
  39 # This would wait indefinitely before v8.28 due to no EPIPE being
  40 # generated due to no data written after the first small amount.
  41 # Also check tail exits if SIGPIPE is being ignored.
  42 # Note 'trap - SIGPIPE' is ineffective if the initiating shell
  43 # has ignored SIGPIPE, but that's not the normal case.
  44 for disposition in '' '-'; do
  45   (trap "$disposition" PIPE;
  46    returns_ 124 timeout 10 \
  47     tail -n2 -f $mode $fastpoll out && touch timed_out) |
  48   head -n2 > out2
  49   test -e timed_out && fail=1
  50   compare exp out2 || fail=1
  51   rm -f timed_out
  52 done
  53
  54 # This would wait indefinitely before v8.28 (until first write)
  55 # test -w /dev/stdout is used to check that >&- is effective
  56 # which was seen not to be the case on NetBSD 7.1 / x86_64:
  57 if env test -w /dev/stdout >/dev/null &&
  58    env test ! -w /dev/stdout >&-; then
  59   (returns_ 1 timeout 10 tail -f $mode $fastpoll /dev/null >&-) || fail=1
  60 fi
  61 done
  62
  63 Exit $fail