tests: cleanup background processes upon interruption

Reap background processes so that:
- Stray processes aren't left on the system
- Files aren't held open causing deletion issues on NFS
- Partitions used to run the tests from can be unmounted

* tests/tail-2/F-vs-missing.sh: Add the `kill && wait` of the
background $pid(s) to cleanup_().
* tests/tail-2/F-vs-rename.sh: Likewise.
* tests/tail-2/f-vs-rename.sh: Likewise.
* tests/tail-2/append-only.sh: Likewise.
* tests/tail-2/assert-2.sh: Likewise.
* tests/tail-2/assert.sh: Likewise.
* tests/tail-2/flush-initial.sh: Likewise.
* tests/tail-2/inotify-hash-abuse.sh: Likewise.
* tests/tail-2/inotify-hash-abuse2.sh: Likewise.
* tests/tail-2/inotify-race.sh: Likewise.
* tests/tail-2/inotify-rotate-resources.sh: Likewise.
* tests/tail-2/inotify-rotate.sh: Likewise.
* tests/tail-2/pid.sh: Likewise.
* tests/tail-2/pipe-f2.sh: Likewise.
* tests/tail-2/retry.sh: Likewise.
* tests/tail-2/symlink.sh: Likewise.
* tests/tail-2/tail-n0f.sh: Likewise.
* tests/tail-2/wait.sh: Likewise.
* tests/cp/existing-perm-race.sh: Likewise.
* tests/cp/file-perm-race.sh: Likewise.
* tests/cp/parent-perm-race.sh: Likewise.
* tests/cp/sparse-to-pipe.sh: Likewise.
* tests/dd/stats.sh: Likewise.
* tests/du/move-dir-while-traversing.sh: Likewise.
* tests/misc/cat-buf.sh: Likewise.
* tests/misc/help-version.sh: Likewise.
* tests/misc/printf-surprise.sh: Likewise.
* tests/misc/sort-compress-proc.sh: Likewise.
* tests/misc/sort-spinlock-abuse.sh: Likewise.
* tests/misc/stdbuf.sh: Likewise.
* tests/misc/tac-continue.sh: Likewise.
* tests/misc/timeout-group.sh: Likewise.
* tests/mv/i-3.sh: Likewise.
* tests/rm/dangling-symlink.sh: Likewise.
* tests/rm/isatty.sh: Likewise.
* cfg.mk (sc_prohibit_test_background_without_cleanup_):
A new syntax-check to ensure cleanup_() is defined
when background tasks are created in a test.

8 files changed, 41 insertions, 17 deletions

diff --git a/tests/misc/cat-buf.sh b/tests/misc/cat-buf.sh
index 68be86e1a..31382481a 100755
--- a/tests/misc/cat-buf.sh
+++ b/tests/misc/cat-buf.sh
@@ -26,6 +26,8 @@ print_ver_ cat
 # write separately.
 mkfifo_or_skip_ fifo
 
+# Terminate any background cp process
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
 
 echo 1 > exp
 
@@ -33,9 +35,9 @@ cat_buf_1()
 {
   local delay="$1"
 
-  dd count=1 if=fifo > out &
+  dd count=1 if=fifo > out & pid=$!
   (echo 1; sleep $delay; echo 2) | cat -v > fifo
-  wait # for dd to complete
+  wait $pid
   compare exp out
 }
 
diff --git a/tests/misc/help-version.sh b/tests/misc/help-version.sh
index 64d6e1642..e0dd721f9 100755
--- a/tests/misc/help-version.sh
+++ b/tests/misc/help-version.sh
@@ -25,6 +25,9 @@ export SHELL
 
 . "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
 
+# Terminate any background processes
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
+
 expected_failure_status_chroot=125
 expected_failure_status_env=125
 expected_failure_status_nice=125
@@ -216,8 +219,8 @@ id_setup () { args=-u; }
 
 # Use env to avoid invoking built-in sleep of Solaris 11's /bin/sh.
 kill_setup () {
-  env sleep 31.5 &
-  args=$!
+  env sleep 10m & pid=$!
+  args=$pid
 }
 
 link_setup () { args="$tmp_in link-target"; }
diff --git a/tests/misc/printf-surprise.sh b/tests/misc/printf-surprise.sh
index 0af64482d..20e6b0988 100755
--- a/tests/misc/printf-surprise.sh
+++ b/tests/misc/printf-surprise.sh
@@ -53,7 +53,10 @@ mkfifo_or_skip_ fifo
 # http://bugs.debian.org/481543#77
 export MALLOC_PERTURB_=0
 
-head -c 10 fifo > out &
+# Terminate any background process
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
+
+head -c 10 fifo > out & pid=$!
 
 # Choosing the virtual memory limit, 11000 is enough, but 10000 is too
 # little and provokes a "memory exhausted" diagnostic on FreeBSD 9.0-p3.
diff --git a/tests/misc/sort-compress-proc.sh b/tests/misc/sort-compress-proc.sh
index a191a3c51..4ad42d514 100755
--- a/tests/misc/sort-compress-proc.sh
+++ b/tests/misc/sort-compress-proc.sh
@@ -20,6 +20,9 @@
 print_ver_ sort
 expensive_
 
+# Terminate any background processes
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
+
 SORT_FAILURE=2
 
 seq -w 2000 > exp || fail=1
@@ -63,7 +66,7 @@ done
 # Ignore a random child process created before 'sort' was exec'ed.
 # This bug was also present in coreutils 8.7.
 #
-( (sleep 1; exec false) &
+( (sleep 1; exec false) & pid=$!
   PRE_COMPRESS='test -f ok || sleep 2'
   POST_COMPRESS='touch ok'
   exec sort --compress-program=./compress -S 1k in >out
diff --git a/tests/misc/sort-spinlock-abuse.sh b/tests/misc/sort-spinlock-abuse.sh
index 31c5aa200..e81abf801 100755
--- a/tests/misc/sort-spinlock-abuse.sh
+++ b/tests/misc/sort-spinlock-abuse.sh
@@ -29,13 +29,16 @@ very_expensive_
 grep '^#define HAVE_PTHREAD_T 1' "$CONFIG_HEADER" > /dev/null ||
   skip_ 'requires pthreads'
 
+# Terminate any background processes
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
+
 seq 100000 > in || framework_failure_
 mkfifo_or_skip_ fifo
 
 # Arrange for sort to require 8.0+ seconds of wall-clock time,
 # while actually using far less than 1 second of CPU time.
 (for i in $(seq 80); do read line; echo $i; sleep .1; done
-  cat > /dev/null) < fifo &
+  cat > /dev/null) < fifo & pid=$!
 
 # However, under heavy load, it can easily take more than
 # one second of CPU time, so set a permissive limit:
diff --git a/tests/misc/stdbuf.sh b/tests/misc/stdbuf.sh
index bb1d40ca5..428d4a2f1 100755
--- a/tests/misc/stdbuf.sh
+++ b/tests/misc/stdbuf.sh
@@ -58,15 +58,18 @@ test $? = 126 || fail=1
 stdbuf -o1 no_such # no such command
 test $? = 127 || fail=1
 
+# Terminate any background processes
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
+
 # Ensure line buffering stdout takes effect
 stdbuf_linebuffer()
 {
   local delay="$1"
 
   printf '1\n' > exp
-  dd count=1 if=fifo > out 2> err &
+  dd count=1 if=fifo > out 2> err & pid=$!
   (printf '1\n'; sleep $delay; printf '2\n') | stdbuf -oL uniq > fifo
-  wait # for dd to complete
+  wait $pid
   compare exp out
 }
 
@@ -78,9 +81,9 @@ stdbuf_unbuffer()
 
   # Ensure un buffering stdout takes effect
   printf '1\n' > exp
-  dd count=1 if=fifo > out 2> err &
+  dd count=1 if=fifo > out 2> err & pid=$!
   (printf '1\n'; sleep $delay; printf '2\n') | stdbuf -o0 uniq > fifo
-  wait # for dd to complete
+  wait $pid
   compare exp out
 }
 
diff --git a/tests/misc/tac-continue.sh b/tests/misc/tac-continue.sh
index 9078cd58d..1389072b4 100755
--- a/tests/misc/tac-continue.sh
+++ b/tests/misc/tac-continue.sh
@@ -33,7 +33,13 @@ if ! test -d "$FULL_PARTITION_TMPDIR"; then
 fi
 
 fp_tmp="$FULL_PARTITION_TMPDIR/tac-cont-$$"
-cleanup_() { rm -f "$fp_tmp"; }
+cleanup_()
+{
+  # Terminate any background process
+  # and remove tmp dir
+  rm -f "$fp_tmp"
+  kill $pid 2>/dev/null && wait $pid
+}
 
 # Make sure we can create an empty file there (i.e., no shortage of inodes).
 if ! touch $fp_tmp; then
@@ -54,7 +60,7 @@ seq 5 > in
 # Give tac a fifo command line argument.
 # This makes it try to create a temporary file in $TMPDIR.
 mkfifo_or_skip_ fifo
-seq 1000 > fifo &
+seq 1000 > fifo & pid=$!
 TMPDIR=$FULL_PARTITION_TMPDIR tac fifo in >out 2>err && fail=1
 
 cat <<\EOF > exp || fail=1
diff --git a/tests/misc/timeout-group.sh b/tests/misc/timeout-group.sh
index 77682920b..054c5aec6 100755
--- a/tests/misc/timeout-group.sh
+++ b/tests/misc/timeout-group.sh
@@ -57,15 +57,17 @@ check_timeout_cmd_running()
     { sleep $delay; return 1; }
 }
 
+# Terminate any background processes
+cleanup_() { kill $pid 2>/dev/null && wait $pid; }
 
 # Start above script in its own group.
 # We could use timeout for this, but that assumes an implementation.
-setsid ./group.sh &
+setsid ./group.sh & pid=$!
 # Wait 6.3s for timeout.cmd to start
 retry_delay_ check_timeout_cmd_running .1 6 || fail=1
 # Simulate a Ctrl-C to the group to test timely exit
 # Note dash doesn't support signalling groups (a leading -)
-env kill -INT -- -$!
+env kill -INT -- -$pid
 wait
 test -e int.received || fail=1
 
@@ -82,8 +84,7 @@ start=$(date +%s)
 # Note the first timeout must send a signal that
 # the second is handling for it to be propagated to the command.
 # SIGINT, SIGTERM, SIGALRM etc. are implicit.
-timeout -sALRM 30 timeout -sINT 25 ./timeout.cmd 20&
-pid=$!
+timeout -sALRM 30 timeout -sINT 25 ./timeout.cmd 20 & pid=$!
 # Wait 6.3s for timeout.cmd to start
 retry_delay_ check_timeout_cmd_running .1 6 || fail=1
 kill -ALRM $pid # trigger the alarm of the first timeout command