Update tcp test cases to verify network socket statistics

Cases Updated are:
1. TCPSOCKET_ECHOTEST_NONBLOCK
2. TCPSOCKET_OPEN_CLOSE_REPEAT
3. TCPSOCKET_OPEN_LIMIT

TESTS/netsocket/tcp/main.cpp

@@ -38,6 +38,10 @@ NetworkInterface *net;
 Timer tc_bucket; // Timer to limit a test cases run time
 }
 
+#if defined(MBED_NW_STATS_ENABLED)
+mbed_stats_socket_t tcp_stats[MBED_CONF_NSAPI_SOCKET_STATS_MAX_COUNT] = {0};
+#endif
+
 char tcp_global::rx_buffer[RX_BUFF_SIZE];
 char tcp_global::tx_buffer[TX_BUFF_SIZE];
 
@@ -115,6 +119,15 @@ int split2half_rmng_tcp_test_time()
     return (tcp_global::TESTS_TIMEOUT - tc_bucket.read()) / 2;
 }
 
+int fetch_stats()
+{
+#if defined(MBED_NW_STATS_ENABLED)
+    return SocketStats::mbed_stats_socket_get_each(&tcp_stats[0], MBED_CONF_NSAPI_SOCKET_STATS_MAX_COUNT);
+#else
+    return 0;
+#endif
+}
+
 // Test setup
 utest::v1::status_t greentea_setup(const size_t number_of_cases)
 {

TESTS/netsocket/tcp/tcp_tests.h

@@ -23,6 +23,11 @@ void drop_bad_packets(TCPSocket &sock, int orig_timeout);
 void fill_tx_buffer_ascii(char *buff, size_t len);
 nsapi_error_t tcpsocket_connect_to_echo_srv(TCPSocket &sock);
 nsapi_error_t tcpsocket_connect_to_discard_srv(TCPSocket &sock);
+int fetch_stats(void);
+
+#if defined(MBED_NW_STATS_ENABLED)
+extern mbed_stats_socket_t tcp_stats[MBED_CONF_NSAPI_SOCKET_STATS_MAX_COUNT];
+#endif
 
 /**
  * Single testcase might take only half of the remaining execution time

TESTS/netsocket/tcp/tcpsocket_echotest.cpp

@@ -114,6 +114,12 @@ void tcpsocket_echotest_nonblock_receiver(void *receive_bytes)
 
 void TCPSOCKET_ECHOTEST_NONBLOCK()
 {
+    int j = 0;
+    int count = fetch_stats();
+    for (; j < count; j++) {
+        TEST_ASSERT_EQUAL(SOCK_CLOSED, tcp_stats[j].state);
+    }
+
     tc_exec_time.start();
     time_allotted = split2half_rmng_tcp_test_time(); // [s]
 
@@ -160,6 +166,14 @@ void TCPSOCKET_ECHOTEST_NONBLOCK()
             bytes2send -= sent;
         }
         printf("[Sender#%02d] bytes sent: %d\n", s_idx, pkt_s);
+        count = fetch_stats();
+        for (j = 0; j < count; j++) {
+            if ((tcp_stats[j].state == SOCK_OPEN) && (tcp_stats[j].proto == NSAPI_TCP)) {
+                break;
+            }
+        }
+        TEST_ASSERT_EQUAL(bytes2send, tcp_stats[j].sent_bytes);
+
         tx_sem.wait(split2half_rmng_tcp_test_time());
         thread->join();
         delete thread;

TESTS/netsocket/tcp/tcpsocket_open_close_repeat.cpp

@@ -26,6 +26,11 @@ using namespace utest::v1;
 
 void TCPSOCKET_OPEN_CLOSE_REPEAT()
 {
+    int count = fetch_stats();
+    for (int j = 0; j < count; j++) {
+        TEST_ASSERT_EQUAL(SOCK_CLOSED,  tcp_stats[j].state);
+    }
+
     TCPSocket *sock = new TCPSocket;
     if (!sock) {
         TEST_FAIL();
@@ -36,4 +41,9 @@ void TCPSOCKET_OPEN_CLOSE_REPEAT()
         TEST_ASSERT_EQUAL(NSAPI_ERROR_OK, sock->close());
     }
     delete sock;
+
+    count = fetch_stats();
+    for (int j = 0; j < count; j++) {
+        TEST_ASSERT_EQUAL(SOCK_CLOSED, tcp_stats[j].state);
+    }
 }

TESTS/netsocket/tcp/tcpsocket_open_limit.cpp

@@ -70,6 +70,15 @@ void TCPSOCKET_OPEN_LIMIT()
             break;
         }
 
+        int count = fetch_stats();
+        int open_count = 0;
+        for (int j = 0; j < count; j++) {
+            if ((tcp_stats[j].state == SOCK_OPEN) && (tcp_stats[j].proto == NSAPI_TCP)) {
+                open_count++;
+            }
+        }
+        TEST_ASSERT(open_count >= 4);
+
         TCPSocketItem *tmp;
         for (TCPSocketItem *it = socket_list_head; it;) {
             ++open_sockets[i];