1 files changed, 90 insertions, 0 deletions
diff --git a/tests/tail-2/wait.sh b/tests/tail-2/wait.sh
new file mode 100755
index 0000000..e9fc1fa
--- /dev/null
+++ b/tests/tail-2/wait.sh
@@ -0,0 +1,90 @@
+#!/bin/sh
+# Make sure that 'tail -f' returns immediately if a file doesn't exist
+# while 'tail -F' waits for it to appear.
+
+# Copyright (C) 2003-2022 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ tail
+
+grep '^#define HAVE_INOTIFY 1' "$CONFIG_HEADER" >/dev/null \
+  && HAVE_INOTIFY=1
+
+inotify_failed_re='inotify (resources exhausted|cannot be used)'
+
+touch here || framework_failure_
+{ touch unreadable && chmod a-r unreadable; } || framework_failure_
+
+# Terminate any background tail process
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
+
+# speedup non inotify case
+fastpoll='-s.1 --max-unchanged-stats=1'
+
+for mode in '' '---disable-inotify'; do
+  returns_ 124 timeout 10 tail $fastpoll -f $mode not_here && fail=1
+
+  if test ! -r unreadable; then # can't test this when root
+    returns_ 124 timeout 10 tail $fastpoll -f $mode unreadable && fail=1
+  fi
+
+  returns_ 124 timeout .1 tail $fastpoll -f $mode here 2>tail.err || fail=1
+
+  # 'tail -F' must wait in any case.
+
+  returns_ 124 timeout .1 tail $fastpoll -F $mode here 2>>tail.err || fail=1
+
+  if test ! -r unreadable; then # can't test this when root
+    returns_ 124 timeout .1 tail $fastpoll -F $mode unreadable || fail=1
+  fi
+
+  returns_ 124 timeout .1 tail $fastpoll -F $mode not_here || fail=1
+
+  grep -Ev "$inotify_failed_re" tail.err > x
+  mv x tail.err
+  compare /dev/null tail.err || fail=1
+  >tail.err
+done
+
+if test "$HAVE_INOTIFY" && test -z "$mode" && is_local_dir_ .; then
+  # Ensure -F never follows a descriptor after rename
+  # either with tiny or significant delays between operations
+  tail_F()
+  {
+    local delay="$1"
+
+    > k && > tail.out && > tail.err || framework_failure_
+    tail $fastpoll -F $mode k >tail.out 2>tail.err & pid=$!
+    sleep $delay
+    mv k l
+    sleep $delay
+    touch k
+    mv k l
+    sleep $delay
+    echo NO >> l
+    sleep $delay
+    cleanup_
+    rm -f k l
+
+    test -s tail.out \
+      && ! grep -E "$inotify_failed_re" tail.err >/dev/null
+  }
+
+  retry_delay_ tail_F 0 1 && { cat tail.out; fail=1; }
+  retry_delay_ tail_F .2 1 && { cat tail.out; fail=1; }
+fi
+
+Exit $fail