fixup! tests: Initial import of congure_reno tests

tests/congure_reno/main.c

@@ -25,6 +25,7 @@
 #include "congure_impl.h"
 
 static int _json_statham(int argc, char **argv);
+static int _set_mss(int argc, char **argv);
 static int _set_cwnd(int argc, char **argv);
 static int _set_ssthresh(int argc, char **argv);
 static int _get_fr_calls(int argc, char **argv);
@@ -34,6 +35,7 @@ static congure_reno_snd_t _congure_state;
 static const shell_command_t shell_commands[] = {
     { "state", "Prints current CongURE state object as JSON", _json_statham },
     { "set_cwnd", "Set cwnd member for CongURE state object", _set_cwnd },
+    { "set_mss", "Set new MSS for CongURE state object", _set_mss },
     { "set_ssthresh", "Set ssthresh member for CongURE state object",
       _set_ssthresh },
     { "get_ff_calls",
@@ -108,6 +110,22 @@ static int _json_statham(int argc, char **argv)
     return 0;
 }
 
+static int _set_mss(int argc, char **argv)
+{
+    uint32_t tmp;
+
+    if (argc < 2) {
+        print_str("{\"error\":\"`mss` argument expected\"}");
+        return 1;
+    }
+    tmp = scn_u32_dec(argv[1], strlen(argv[1]));
+    if (tmp > CONGURE_WND_SIZE_MAX) {
+        print_str("{\"error\":\"`mss` not 16 bit wide\"}\n");
+    }
+    congure_reno_set_mss(&_congure_state, (congure_wnd_size_t)tmp);
+    return 0;
+}
+
 static int _set_cwnd(int argc, char **argv)
 {
     uint32_t tmp;
@@ -118,7 +136,7 @@ static int _set_cwnd(int argc, char **argv)
     }
     tmp = scn_u32_dec(argv[1], strlen(argv[1]));
     if (tmp > CONGURE_WND_SIZE_MAX) {
-        print_str("{\"error\":\"`ssthresh` not 16 bit wide\"}\n");
+        print_str("{\"error\":\"`cwnd` not 16 bit wide\"}\n");
     }
     _congure_state.super.cwnd = (congure_wnd_size_t)tmp;
     return 0;

tests/congure_reno/tests/01-run.py

@@ -7,6 +7,7 @@
 # directory for more details.
 
 import logging
+import sys
 import unittest
 
 from riotctrl.ctrl import RIOTCtrl
@@ -17,17 +18,23 @@
 class TestCongUREBase(unittest.TestCase):
     # pylint: disable=too-many-public-methods
     # it's just one more ...
+    DEBUG = False
+
     @classmethod
     def setUpClass(cls):
         cls.ctrl = RIOTCtrl()
         cls.ctrl.start_term()
+        if cls.DEBUG:
+            cls.ctrl.term.logfile = sys.stdout
         cls.ctrl.reset()
         cls.shell = ShellInteraction(cls.ctrl)
         cls.json_parser = RapidJSONShellInteractionParser()
         cls.json_parser.set_parser_args(
             parse_mode=rapidjson.PM_TRAILING_COMMAS
         )
         cls.logger = logging.getLogger(cls.__name__)
+        if cls.DEBUG:
+            cls.logger.setLevel(logging.DEBUG)
 
     @classmethod
     def tearDownClass(cls):
@@ -89,6 +96,9 @@ def get_ff_calls(self):
     def set_same_wnd_adv(self, value):
         self.exec_cmd(f'set_same_wnd_adv {value:d}')
 
+    def set_mss(self, mss):
+        self.exec_cmd(f'set_mss {mss}')
+
     def set_cwnd(self, cwnd):
         self.exec_cmd(f'set_cwnd {cwnd}')
 
@@ -111,17 +121,17 @@ def cong_report_msg_sent(self, msg_size):
     def cong_report_msg_discarded(self, msg_size):
         return self.cong_report('msg_discarded', msg_size)
 
-    def _report_msg_timeout_lost(self, cmd, msgs):
+    def _report_msgs_timeout_lost(self, cmd, msgs):
         args = []
         for msg in msgs:
             args.extend((msg['send_time'], msg['size'], msg['resends']))
         return self.cong_report(cmd, *args)
 
-    def cong_report_msg_timeout(self, msgs):
-        return self._report_msg_timeout_lost('msg_timeout', msgs)
+    def cong_report_msgs_timeout(self, msgs):
+        return self._report_msgs_timeout_lost('msgs_timeout', msgs)
 
-    def cong_report_msg_lost(self, msgs):
-        return self._report_msg_timeout_lost('msg_lost', msgs)
+    def cong_report_msgs_lost(self, msgs):
+        return self._report_msgs_timeout_lost('msgs_lost', msgs)
 
     def cong_report_msg_acked(self, msg, ack):
         if isinstance(ack['clean'], bool):
@@ -228,6 +238,60 @@ def setUp(self):
         self.assertIn('setup', res)
         self.cong_init()
 
+    def test_mss_2200(self):
+        """
+        https://tools.ietf.org/html/rfc5681#section-3.1
+
+        > IW, the initial value of cwnd, MUST be set using the following
+        > guidelines as an upper bound.
+        >
+        > If SMSS > 2190 bytes:
+        >     IW = 2 * SMSS bytes and MUST NOT be more than 2 segments
+        > If (SMSS > 1095 bytes) and (SMSS <= 2190 bytes):
+        >     IW = 3 * SMSS bytes and MUST NOT be more than 3 segments
+        > if SMSS <= 1095 bytes:
+        >     IW = 4 * SMSS bytes and MUST NOT be more than 4 segments
+        """
+        self.set_mss(2200)
+        state = self.cong_state()
+        self.assertEqual(2200, state['mss'])
+        # (SMSS > 2190 bytes)
+        self.assertGreater(state['mss'], state['consts']['cwnd_upper'])
+        # (SMSS > 1095 bytes)
+        self.assertGreater(state['mss'], state['consts']['cwnd_lower'])
+        # as such, IW = 2 * SMSS bytes
+        self.assertEqual(state['cwnd'], 2 * state['mss'])
+        # We start with slow start
+        self.assertSlowStart(state)
+        self.assertNotInFastRetransmit(state)
+
+    def test_mss_1095(self):
+        """
+        https://tools.ietf.org/html/rfc5681#section-3.1
+
+        > IW, the initial value of cwnd, MUST be set using the following
+        > guidelines as an upper bound.
+        >
+        > If SMSS > 2190 bytes:
+        >     IW = 2 * SMSS bytes and MUST NOT be more than 2 segments
+        > If (SMSS > 1095 bytes) and (SMSS <= 2190 bytes):
+        >     IW = 3 * SMSS bytes and MUST NOT be more than 3 segments
+        > if SMSS <= 1095 bytes:
+        >     IW = 4 * SMSS bytes and MUST NOT be more than 4 segments
+        """
+        self.set_mss(1095)
+        state = self.cong_state()
+        self.assertEqual(1095, state['mss'])
+        # (SMSS < 2190 bytes)
+        self.assertLess(state['mss'], state['consts']['cwnd_upper'])
+        # (SMSS < 1095 bytes)
+        self.assertLessEqual(state['mss'], state['consts']['cwnd_lower'])
+        # as such, IW = 4 * SMSS bytes
+        self.assertEqual(state['cwnd'], 4 * state['mss'])
+        # We start with slow start
+        self.assertSlowStart(state)
+        self.assertNotInFastRetransmit(state)
+
     def test_slow_start_increase_small_N(self):
         # pylint: disable=invalid-name
         # name chosen to be in line with RFC
@@ -325,7 +389,7 @@ def _send_msg_and_timeout(self, msgs):
             flight_size += msg['size']
         state = self.cong_state()
         self.assertEqual(state['in_flight_size'], flight_size)
-        res = self.cong_report_msg_timeout(msgs)
+        res = self.cong_report_msgs_timeout(msgs)
         self.assertIsNone(res)
 
     def test_reduce_ssthresh_small_flight_size(self):
@@ -680,7 +744,7 @@ def test_msg_discarded(self):
         state = self.cong_state()
         self.assertEqual(state['in_flight_size'], 0)
 
-    def test_msg_lost(self):
+    def test_msgs_lost(self):
         """
         RFC 5681 does not say anything about explicitly lost messages.
         It's a feature of CongURE. Calling it, should enforce fast retransmit,
@@ -695,7 +759,7 @@ def test_msg_lost(self):
             flight_size += msg['size']
         state = self.cong_state()
         self.assertEqual(state['in_flight_size'], flight_size)
-        res = self.cong_report_msg_lost(msgs)
+        res = self.cong_report_msgs_lost(msgs)
         self.assertIsNone(res)
         state = self.cong_state()
         self.assertEqual(1, self.get_ff_calls())
@@ -756,7 +820,7 @@ def test_fast_retransmit_decrease(self):
             flight_size += msg['size']
         state = self.cong_state()
         self.assertEqual(state['in_flight_size'], flight_size)
-        res = self.cong_report_msg_lost(msgs)
+        res = self.cong_report_msgs_lost(msgs)
         self.assertIsNone(res)
         state = self.cong_state()
         self.assertEqual(state['cwnd'], init_cwnd // 8)