[LTP] [RFC PATCH v4 2/5] shell: Introduce TST_TIMEOUT variable, add checks

[Petr Vorel]

to unify shell API with C API.

TST_TIMEOUT should be set in tests only, it's equivalent
of tst_test->timeout in C API.

Add checks requiring both TST_TIMEOUT and LTP_TIMEOUT_MUL >= 1,
that allow to set TST_TIMEOUT lower than the default 300 sec
(might be useful for some case).

LTP_TIMEOUT_MUL can be float, but will be ceiled to int.
Using float would require awk/bc, which is unnecessary dependency
and code complication (we do not care that much if it's multiplied
precisely as far as the resulting timeout is never smaller than
the precise calculation).

Also added cut dependency to _tst_setup_timer(), but that's not
a problem as it was already required for shell API in tst_run().

Suggested-by: Clemens Famulla-Conrad <cfamullaconrad@suse.de>
Reviewed-by: Li Wang <liwang@redhat.com>
Reviewed-by: Clemens Famulla-Conrad <cfamullaconrad@suse.de>
Signed-off-by: Petr Vorel <pvorel@suse.cz>
---
 doc/test-writing-guidelines.txt |  8 ++++++--
 testcases/lib/tst_test.sh       | 32 ++++++++++++++++++++++++++++++--
 2 files changed, 36 insertions(+), 4 deletions(-)

diff --git a/doc/test-writing-guidelines.txt b/doc/test-writing-guidelines.txt
index 6643fc7c1..69da6c495 100644
--- a/doc/test-writing-guidelines.txt
+++ b/doc/test-writing-guidelines.txt
@@ -2109,8 +2109,8 @@ tst_run
 '$TST_TEST_DATA' can be used with '$TST_CNT'. If '$TST_TEST_DATA_IFS' not specified,
 space as default value is used. Of course, it's possible to use separate functions.
 
-2.3.2 Library variables
-^^^^^^^^^^^^^^^^^^^^^^^
+2.3.2 Library environment variables for shell
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
 Similarily to the C library various checks and preparations can be requested
 simply by setting right '$TST_NEEDS_FOO'.
@@ -2126,6 +2126,10 @@ simply by setting right '$TST_NEEDS_FOO'.
                        the test (see below).
 | 'TST_NEEDS_MODULE' | Test module name needed for the test (see below).
 | 'TST_NEEDS_DRIVERS'| Checks kernel drivers support for the test.
+| 'TST_TIMEOUT'      | Maximum timeout set for the test in sec. Must be int >= 1,
+                       or -1 (special value to disable timeout), default is 300.
+                       Variable is meant be set in tests, not by user.
+                       It's equivalent of `tst_test.timeout` in C.
 |=============================================================================
 
 NOTE: Network tests (see testcases/network/README.md) use additional variables
diff --git a/testcases/lib/tst_test.sh b/testcases/lib/tst_test.sh
index ca63745fd..977ffd97e 100644
--- a/testcases/lib/tst_test.sh
+++ b/testcases/lib/tst_test.sh
@@ -379,9 +379,37 @@ _tst_rescmp()
 
 _tst_setup_timer()
 {
+	TST_TIMEOUT=${TST_TIMEOUT:-300}
 	LTP_TIMEOUT_MUL=${LTP_TIMEOUT_MUL:-1}
 
-	local sec=$((300 * LTP_TIMEOUT_MUL))
+	if [ "$TST_TIMEOUT" = -1 ]; then
+		tst_res TINFO "Timeout per run is disabled"
+		return
+	fi
+
+	local err="LTP_TIMEOUT_MUL must be number >= 1!"
+
+	tst_is_num "$LTP_TIMEOUT_MUL" || tst_brk TCONF "$err ($LTP_TIMEOUT_MUL)"
+
+	if ! tst_is_int "$LTP_TIMEOUT_MUL"; then
+		tst_test_cmds cut
+		LTP_TIMEOUT_MUL=$(echo "$LTP_TIMEOUT_MUL" | cut -d. -f1)
+		LTP_TIMEOUT_MUL=$((LTP_TIMEOUT_MUL+1))
+		tst_res TINFO "ceiling LTP_TIMEOUT_MUL to $LTP_TIMEOUT_MUL"
+	fi
+	[ "$LTP_TIMEOUT_MUL" -ge 1 ] || tst_brk TCONF "$err ($LTP_TIMEOUT_MUL)"
+
+	if ! tst_is_int "$TST_TIMEOUT" || [ "$TST_TIMEOUT" -lt 1 ]; then
+		tst_brk TBROK "TST_TIMEOUT must be int >= 1! ($TST_TIMEOUT)"
+	fi
+
+	local sec
+	if [ "$is_float" ]; then
+		sec=`echo | awk '{printf("%d\n", '$TST_TIMEOUT' * '$LTP_TIMEOUT_MUL'+ 0.5)}'`
+	else
+		sec=$((TST_TIMEOUT * LTP_TIMEOUT_MUL))
+	fi
+
 	local h=$((sec / 3600))
 	local m=$((sec / 60 % 60))
 	local s=$((sec % 60))
@@ -418,7 +446,7 @@ tst_run()
 			NEEDS_CMDS|NEEDS_MODULE|MODPATH|DATAROOT);;
 			NEEDS_DRIVERS|FS_TYPE|MNTPOINT|MNT_PARAMS);;
 			IPV6|IPVER|TEST_DATA|TEST_DATA_IFS);;
-			RETRY_FUNC|RETRY_FN_EXP_BACKOFF);;
+			RETRY_FUNC|RETRY_FN_EXP_BACKOFF|TIMEOUT);;
 			NET_MAX_PKT);;
 			*) tst_res TWARN "Reserved variable TST_$_tst_i used!";;
 			esac
-- 
2.23.0