support/testing: add ntp runtime test

Signed-off-by: Julien Olivain <ju.o@free.fr>
Signed-off-by: Arnout Vandecappelle <arnout@mind.be>
(cherry picked from commit c986928affc59f5bbefae8c7af963eaf45fdc8c8)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

DEVELOPERS

@@ -1835,6 +1835,8 @@ F:	support/testing/tests/package/test_netsnmp/
 F:	support/testing/tests/package/test_nftables.py
 F:	support/testing/tests/package/test_nftables/
 F:	support/testing/tests/package/test_ngrep.py
+F:	support/testing/tests/package/test_ntp.py
+F:	support/testing/tests/package/test_ntp/
 F:	support/testing/tests/package/test_numactl.py
 F:	support/testing/tests/package/test_numactl/
 F:	support/testing/tests/package/test_octave.py

support/testing/tests/package/test_ntp.py

@@ -0,0 +1,86 @@
+import os
+import re
+import time
+
+import infra.basetest
+
+
+class TestNtp(infra.basetest.BRTest):
+    rootfs_overlay = \
+        infra.filepath("tests/package/test_ntp/rootfs-overlay")
+    config = infra.basetest.BASIC_TOOLCHAIN_CONFIG + \
+        f"""
+        BR2_PACKAGE_NTP=y
+        BR2_PACKAGE_NTP_NTPD=y
+        BR2_PACKAGE_NTP_NTPQ=y
+        BR2_ROOTFS_OVERLAY="{rootfs_overlay}"
+        BR2_TARGET_ROOTFS_CPIO=y
+        # BR2_TARGET_ROOTFS_TAR is not set
+        """
+
+    def dict_from_ntpq_output(self, output):
+        d = {}
+        for line in output:
+            if ':' not in line:
+                continue
+            fields = re.split(r":", line, maxsplit=2)
+            name = fields[0].strip()
+            value = fields[1].strip()
+            d[name] = value
+        return d
+
+    def test_run(self):
+        cpio_file = os.path.join(self.builddir, "images", "rootfs.cpio")
+        self.emulator.boot(arch="armv5",
+                           kernel="builtin",
+                           options=["-initrd", cpio_file])
+        self.emulator.login()
+
+        # Check our binaries can execute.
+        self.assertRunOk("ntpd --version")
+        self.assertRunOk("ntpq --version")
+
+        # The ntp daemon is expected to be started from init startup
+        # scripts, for the Buildroot package recipe. We wait a bit
+        # here to let the daemon settle. The next test step checks for
+        # the local peer to be the system peer (by checking the
+        # '*'). If querying the peers too soon after startup the peer
+        # will not be marked as such.
+        time.sleep(3 * self.timeout_multiplier)
+
+        # We query the ntp daemon peers. From our test configuration
+        # file, we should have exactly one.
+        out, ret = self.emulator.run("ntpq --peers")
+        self.assertEqual(ret, 0)
+        # ntpq --peers produces two lines of headers. So we check we
+        # have at least 3 lines of output.
+        self.assertGreaterEqual(len(out), 3)
+        # We check we see our undisciplined local clock and it's the
+        # system peer.
+        self.assertTrue(out[2].startswith("*LOCAL(0)"))
+
+        # We query the refid variable. We expect to see our
+        # undisciplined local clock.
+        out, ret = self.emulator.run("ntpq -c 'readvar 0 refid'")
+        self.assertEqual(ret, 0)
+        self.assertEqual(out[0], "refid=LOCAL(0)")
+
+        # We query the ntp system info. We check the reference ID is
+        # the same as in the test configuration file.
+        out, ret = self.emulator.run("ntpq -c sysinfo")
+        self.assertEqual(ret, 0)
+        sysinfo = self.dict_from_ntpq_output(out)
+        refid = "reference ID"
+        self.assertIn(refid, sysinfo)
+        self.assertEqual(sysinfo[refid], "127.127.1.0")
+
+        # Finally, we query the ntp system statistics. We check we can
+        # see some uptime. We waited a bit at the beginning of this
+        # test, plus the few queries we previously did should have
+        # accumulated some uptime.
+        out, ret = self.emulator.run("ntpq -c sysstats")
+        self.assertEqual(ret, 0)
+        sysstats = self.dict_from_ntpq_output(out)
+        up = "uptime"
+        self.assertIn(up, sysstats)
+        self.assertGreater(int(sysstats[up]), 0)

support/testing/tests/package/test_ntp/rootfs-overlay/etc/ntp.conf

@@ -0,0 +1,10 @@
+# Set an undisciplined local clock for testing without the need of
+# network connectivity.
+server 127.127.1.0 iburst prefer
+fudge  127.127.1.0 stratum 10
+
+# Keep standard access control setup. The test is doing local queries
+# from 127.0.0.1.
+restrict default nomodify nopeer noquery limited kod
+restrict 127.0.0.1
+restrict [::1]