tests: fix races in and standardize the tail tests

* tests/tail-2/F-vs-missing.sh: Use standard "fastpoll" options
(-s.1 --max-unchanged-stats=1) to speedup the non-inotify case.
Add the non-inotify case to the test. `wait` on the background
tail process to terminate which should avoid the need for the
non standard `retry_delay_ cleanup ...` on NFS.
* tests/tail-2/F-vs-rename.sh: Remove 'out' at the start of the loop,
to avoid a race in checking its contents.  Also ensure 'a' & 'b'
files are present before the tail process starts.  Use the standard
"fastpoll" options as above.
* tests/tail-2/f-vs-rename.sh: Likewise.
* tests/tail-2/append-only.sh: Use more standard variable names.
* tests/tail-2/flush-initial.sh: Use "fastpoll" options for
non-inotify platforms.  Also `wait` on the background tail to avoid
stray processes and file cleanup issues on NFS.
* tests/tail-2/inotify-hash-abuse.sh: Always run non-inotify case.
Use "fastpoll" options.  Use a more standard retry_delay_ instead
of a hardcoded sleep loop.  Add a `wait` on the background tail.
* tests/tail-2/inotify-hash-abuse2.sh: Likewise.
* tests/tail-2/inotify-rotate-resources.sh: Wait just on the
specific tail $pid needed.
* tests/tail-2/inotify-rotate.sh: Use "fastpoll" options.
* tests/tail-2/pid.sh: Use standard variable names.
Add a `wait` on the background tails.
* tests/tail-2/pipe-f2.sh: Likewise.
* tests/tail-2/tail-n0f.sh: Likewise.
* tests/tail-2/retry.sh: Use "fastpoll" options.
* tests/tail-2/symlink.sh: Likewise.
* tests/tail-2/wait.sh: Likewise.  Speedup by using sub second
parameters to timeout(1).  Improve the part ensuring that
-F never follows a renamed file.
* tests/tail-2/infloop-1.sh: Remove invalid test.  tail(1) was not
being passed the --pid=$yes_pid option, retry_delay_ wasn't used
to avoid races, and yes could write huge files before being killed.
* tests/local.mk: Remove the invalid test reference.
* tests/tail-2/assert-2.sh: Rewrite using retry_delay_().  Since
no longer hardcoding large delays, remove the VERY_EXPENSIVE tag.
* tests/tail-2/assert.sh: Likewise.

1 files changed, 17 insertions, 9 deletions

diff --git a/tests/tail-2/symlink.sh b/tests/tail-2/symlink.sh
index 274df9587..9f1a2010f 100755
--- a/tests/tail-2/symlink.sh
+++ b/tests/tail-2/symlink.sh
@@ -36,15 +36,20 @@ wait4lines_ ()
   [ "$(countlines_)" -ge "$elc" ] || { sleep $delay; return 1; }
 }
 
+# speedup non inotify case
+fastpoll='-s.1 --max-unchanged-stats=1'
+
 # Ensure changing targets of cli specified symlinks are handled.
 # Prior to v8.22, inotify would fail to recognize changes in the targets.
 # Clear 'out' so that we can check its contents without races.
 >out                            || framework_failure_
 ln -nsf target symlink          || framework_failure_
-timeout 10 tail -s.1 -F symlink >out 2>&1 & pid=$!
-retry_delay_ wait4lines_ .1 6 1 || fail=1  # Wait for "cannot open..."
-echo "X" > target               || fail=1
-retry_delay_ wait4lines_ .1 6 3 || fail=1  # Wait for the expected output.
+timeout 10 tail $fastpoll -F symlink >out 2>&1 & pid=$!
+# Wait for "cannot open..."
+retry_delay_ wait4lines_ .1 6 1 || { cat out; fail=1; }
+echo "X" > target               || framework_failure_
+# Wait for the expected output.
+retry_delay_ wait4lines_ .1 6 3 || { cat out; fail=1; }
 kill $pid
 wait $pid
 # Expect 3 lines in the output file.
@@ -60,12 +65,15 @@ rm -f target out           || framework_failure_
 >out                            || framework_failure_
 echo "X1" > target1             || framework_failure_
 ln -nsf target1 symlink         || framework_failure_
-timeout 10 tail -s.1 -F symlink >out 2>&1 & pid=$!
-retry_delay_ wait4lines_ .1 6 1 || fail=1  # Wait for the expected output.
+timeout 10 tail $fastpoll -F symlink >out 2>&1 & pid=$!
+# Wait for the expected output.
+retry_delay_ wait4lines_ .1 6 1 || { cat out; fail=1; }
 ln -nsf target2 symlink         || framework_failure_
-retry_delay_ wait4lines_ .1 6 2 || fail=1  # Wait for "become inaccess..."
-echo "X2" > target2             || fail=1
-retry_delay_ wait4lines_ .1 6 4 || fail=1  # Wait for the expected output.
+# Wait for "become inaccess..."
+retry_delay_ wait4lines_ .1 6 2 || { cat out; fail=1; }
+echo "X2" > target2             || framework_failure_
+# Wait for the expected output.
+retry_delay_ wait4lines_ .1 6 4 || { cat out; fail=1; }
 kill $pid
 wait $pid
 # Expect 4 lines in the output file.