timeout: --foreground, --preserve-status, and --signal.

--signal is simply a synonym for the exiting -s.

--foreground disables functionality we didn't yet have: putting the
child into a new process group. I've added the functionality and the
flag to disable it.

--preserve-status also makes it clear that our exit statuses didn't match
the coreutils version. In addition to callers that use --preserve-status
to get away from this madness, I also have callers that check for
specific exit values. This patch implements --preserve-status but also
fixes all the other exit statuses.

(The "125" exit value is broken for toybox in the same way that
`toybox grep --whoops ; echo $?` is. To fix this, we'd need some way to
signal that command-line parsing failures should exit with a different
value than the usual 1 --- 2 for grep, 125 for timeout. I've done as much
as grep manages, and left a TODO.)

Also add timeout tests. I couldn't think of an easy test for
--foreground, so I tested that manually with strace.

Also add some newlines to the `toybox --help` output to make it easier
to find the different sections, and expand the section on durations to
call out that fractions are supported as a matter of policy.

As long as timeout and sleep have text describing the duration syntax,
make them the same. (Personally I'd remove both in favor of the `toybox
--help` output, but as long as they're duplicated, keep them consistent.)

Also remove the SLEEP_FLOAT variant --- xparsetime means that sleep no
longer requires floating point to support sub-second resolution.

1 files changed, 19 insertions, 0 deletions

diff --git a/tests/timeout.test b/tests/timeout.test
new file mode 100644
index 00000000..5ca7cc90
--- /dev/null
+++ b/tests/timeout.test
@@ -0,0 +1,19 @@
+#!/bin/bash
+
+[ -f testing.sh ] && . testing.sh
+
+#testing "name" "command" "result" "infile" "stdin"
+
+# timeout's exit value is complicated!
+testcmd "times out" '.1 sleep 100 ; echo $?'  '124\n' '' ''
+testcmd "failure" '-s MONKEY .1 sleep 100 2>/dev/null ; echo $?' '125\n' '' ''
+testcmd "can't execute" '.1 / 2>/dev/null ; echo $?' '126\n' '' ''
+testcmd "can't find" '.1 /does/not/exist 2>/dev/null ; echo $?' '127\n' '' ''
+testcmd "custom signal" '-s 3 .1 sleep 100; echo $?' '124\n' '' ''
+testcmd "killed" '-s 9 .1 sleep 100; echo $?' '137\n' '' ''
+testcmd "TERM" '-s TERM .1 sleep 100; echo $?' '124\n' '' ''
+testcmd "exit 0" '.1 true ; echo $?' '0\n' '' ''
+testcmd "exit 1" '.1 false ; echo $?' '1\n' '' ''
+
+testcmd "--preserve-status" '--preserve-status .1 sleep 100 ; echo $?' '143\n' '' ''
+testcmd "--preserve-status killed" '--preserve-status -s 9 .1 sleep 100 ; echo $?' '137\n' '' ''