Diff: TESTS/unit_tests/default/main.cpp

Revision:

1:8ea78dce6b36

Child:

4:2bf3875a13f1

diff -r 649a63e69435 -r 8ea78dce6b36 TESTS/unit_tests/default/main.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/TESTS/unit_tests/default/main.cpp	Mon Jun 26 13:49:08 2017 +0100
@@ -0,0 +1,1093 @@
+#include "UbloxATCellularInterfaceN2xx.h"
+#include "greentea-client/test_env.h"
+#include "unity.h"
+#include "utest.h"
+#include "UDPSocket.h"
+#ifdef FEATURE_COMMON_PAL
+#include "mbed_trace.h"
+#define TRACE_GROUP "TEST"
+#else
+#define tr_debug(format, ...) debug(format "\n", ## __VA_ARGS__)
+#define tr_info(format, ...)  debug(format "\n", ## __VA_ARGS__)
+#define tr_warn(format, ...)  debug(format "\n", ## __VA_ARGS__)
+#define tr_error(format, ...) debug(format "\n", ## __VA_ARGS__)
+#endif
+
+using namespace utest::v1;
+
+// IMPORTANT!!! if you make a change to the tests here you should
+// check whether the same change should be made to the tests under
+// the PPP interface.
+
+// NOTE: these test are only as reliable as UDP across the internet
+// over a radio link.  The tests expect an NTP server to respond
+// to UDP packets and, if configured, an echo server to respond
+// to UDP packets.  This simply may not happen.  Please be patient.
+
+// ----------------------------------------------------------------
+// COMPILE-TIME MACROS
+// ----------------------------------------------------------------
+
+// These macros can be overridden with an mbed_app.json file and
+// contents of the following form:
+//
+//{
+//    "config": {
+//        "default-pin": {
+//            "value": "\"1234\""
+//        }
+//}
+//
+// See the template_mbed_app.txt in this directory for a fuller example.
+
+// Whether debug trace is on
+#ifndef MBED_CONF_APP_DEBUG_ON
+# define MBED_CONF_APP_DEBUG_ON false
+#endif
+
+// Run the SIM change tests, which require the DEFAULT_PIN
+// above to be correct for the board on which the test
+// is being run (and the SIM PIN to be disabled before tests run).
+#ifndef MBED_CONF_APP_RUN_SIM_PIN_CHANGE_TESTS
+# define MBED_CONF_APP_RUN_SIM_PIN_CHANGE_TESTS 0
+#endif
+
+#if MBED_CONF_APP_RUN_SIM_PIN_CHANGE_TESTS
+# ifndef MBED_CONF_APP_DEFAULT_PIN
+#   error "MBED_CONF_APP_DEFAULT_PIN must be defined to run the SIM tests"
+# endif
+# ifndef MBED_CONF_APP_ALT_PIN
+#   error "MBED_CONF_APP_ALT_PIN must be defined to run the SIM tests"
+# endif
+# ifndef MBED_CONF_APP_INCORRECT_PIN
+#   error "MBED_CONF_APP_INCORRECT_PIN must be defined to run the SIM tests"
+# endif
+#endif
+
+// The credentials of the SIM in the board.
+#ifndef MBED_CONF_APP_DEFAULT_PIN
+// Note: if PIN is enabled on your SIM, or you wish to run the SIM PIN change
+// tests, you must define the PIN for your SIM (see note above on using
+// mbed_app.json to do so).
+# define MBED_CONF_APP_DEFAULT_PIN "0000"
+#endif
+#ifndef MBED_CONF_APP_APN
+# define MBED_CONF_APP_APN         NULL
+#endif
+#ifndef MBED_CONF_APP_USERNAME
+# define MBED_CONF_APP_USERNAME    NULL
+#endif
+#ifndef MBED_CONF_APP_PASSWORD
+# define MBED_CONF_APP_PASSWORD    NULL
+#endif
+
+// Alternate PIN to use during pin change testing
+#ifndef MBED_CONF_APP_ALT_PIN
+# define MBED_CONF_APP_ALT_PIN    "9876"
+#endif
+
+// A PIN that is definitely incorrect
+#ifndef MBED_CONF_APP_INCORRECT_PIN
+# define MBED_CONF_APP_INCORRECT_PIN "1530"
+#endif
+
+// Servers and ports
+#ifdef MBED_CONF_APP_ECHO_SERVER
+# ifndef MBED_CONF_APP_ECHO_UDP_PORT
+#  error "MBED_CONF_APP_ECHO_UDP_PORT (the port on which your echo server echoes UDP packets) must be defined"
+# endif
+# ifndef MBED_CONF_APP_ECHO_TCP_PORT
+#  error "MBED_CONF_APP_ECHO_TCP_PORT (the port on which your echo server echoes TCP packets) must be defined"
+# endif
+#endif
+
+#ifndef MBED_CONF_APP_NTP_SERVER
+# define MBED_CONF_APP_NTP_SERVER "80.86.38.193"
+#else
+# ifndef MBED_CONF_APP_NTP_PORT
+#  error "MBED_CONF_APP_NTP_PORT must be defined if MBED_CONF_APP_NTP_SERVER is defined"
+# endif
+#endif
+#ifndef MBED_CONF_APP_NTP_PORT
+# define MBED_CONF_APP_NTP_PORT 123
+#endif
+
+#ifndef MBED_CONF_APP_LOCAL_PORT
+# define MBED_CONF_APP_LOCAL_PORT 15
+#endif
+
+// UDP packet size limit for testing
+#ifndef MBED_CONF_APP_UDP_MAX_PACKET_SIZE
+#  define MBED_CONF_APP_UDP_MAX_PACKET_SIZE 1024
+#endif
+
+// The maximum size of UDP data fragmented across
+// multiple packets
+#ifndef MBED_CONF_APP_UDP_MAX_FRAG_PACKET_SIZE
+# define MBED_CONF_APP_UDP_MAX_FRAG_PACKET_SIZE 1500
+#endif
+
+// TCP packet size limit for testing
+#ifndef MBED_CONF_APP_MBED_CONF_APP_TCP_MAX_PACKET_SIZE
+# define MBED_CONF_APP_TCP_MAX_PACKET_SIZE 1500
+#endif
+
+// The number of retries for UDP exchanges
+#define NUM_UDP_RETRIES 5
+
+// How long to wait for stuff to travel in the async echo tests
+#define ASYNC_TEST_WAIT_TIME 10000
+
+// The maximum number of sockets that can be open at one time
+#define MAX_NUM_SOCKETS 7
+
+// ----------------------------------------------------------------
+// PRIVATE VARIABLES
+// ----------------------------------------------------------------
+
+#ifdef FEATURE_COMMON_PAL
+// Lock for debug prints
+static Mutex mtx;
+#endif
+
+// An instance of the cellular interface
+static UbloxATCellularInterfaceN2xx *interface;
+
+// Connection flag
+static bool connection_has_gone_down = false;
+
+// Data to exchange
+static const char send_data[] =  "_____0000:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0100:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0200:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0300:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0400:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0500:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0600:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0700:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0800:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____0900:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1000:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1100:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1200:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1300:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1400:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1500:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1600:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1700:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1800:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____1900:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789"
+                                 "_____2000:0123456789012345678901234567890123456789"
+                                 "01234567890123456789012345678901234567890123456789";
+
+// ----------------------------------------------------------------
+// PRIVATE FUNCTIONS
+// ----------------------------------------------------------------
+
+#ifdef FEATURE_COMMON_PAL
+// Locks for debug prints
+static void lock()
+{
+    mtx.lock();
+}
+
+static void unlock()
+{
+    mtx.unlock();
+}
+#endif
+
+// Callback in case the connection goes down
+static void connection_down_cb(nsapi_error_t err)
+{
+    connection_has_gone_down = true;
+}
+
+#ifdef MBED_CONF_APP_ECHO_SERVER
+// Make sure that size is greater than 0 and no more than limit,
+// useful since, when moduloing a very large number number,
+// compilers sometimes screw up and produce a small *negative*
+// number.  Who knew?  For example, GCC decided that
+// 492318453 (0x1d582ef5) modulo 508 was -47 (0xffffffd1).
+static int fix (int size, int limit)
+{
+    if (size <= 0) {
+        size = limit / 2; // better than 1
+    } else if (size > limit) {
+        size = limit;
+    }
+
+    return size;
+}
+
+// Do a UDP socket echo test to a given host of a given packet size
+static void do_udp_echo(UDPSocket *sock, SocketAddress *host_address, int size)
+{
+    bool success = false;
+    void * recv_data = malloc (size);
+    SocketAddress sender_address;
+    TEST_ASSERT(recv_data != NULL);
+
+    // Retry this a few times, don't want to fail due to a flaky link
+    for (int x = 0; !success && (x < NUM_UDP_RETRIES); x++) {
+        tr_debug("Echo testing UDP packet size %d byte(s), try %d.", size, x + 1);
+        if ((sock->sendto(*host_address, (void*) send_data, size) == size) &&
+            (sock->recvfrom(&sender_address, recv_data, size) == size)) {
+            TEST_ASSERT (memcmp(send_data, recv_data, size) == 0);
+            TEST_ASSERT (strcmp(sender_address.get_ip_address(), host_address->get_ip_address()) == 0);
+            TEST_ASSERT (sender_address.get_port() == host_address->get_port());
+            success = true;
+        }
+    }
+    TEST_ASSERT (success);
+    TEST_ASSERT(!connection_has_gone_down);
+
+    free (recv_data);
+}
+
+// The asynchronous callback
+static void async_cb(bool *callback_triggered)
+{
+
+    TEST_ASSERT (callback_triggered != NULL);
+    *callback_triggered = true;
+}
+
+// Do a UDP echo but using the asynchronous interface; we can exchange
+// packets longer in size than one UDP packet this way
+static void do_udp_echo_async(UDPSocket *sock, SocketAddress *host_address,
+                              int size, bool *callback_triggered)
+{
+    void * recv_data = malloc (size);
+    int recv_size = 0;
+    SocketAddress sender_address;
+    Timer timer;
+    int x, y, z;
+    TEST_ASSERT(recv_data != NULL);
+
+    *callback_triggered = false;
+    for (y = 0; (recv_size < size) && (y < NUM_UDP_RETRIES); y++) {
+        tr_debug("Echo testing UDP packet size %d byte(s) async, try %d.", size, y + 1);
+        recv_size = 0;
+        // Retry this a few times, don't want to fail due to a flaky link
+        if (sock->sendto(*host_address, (void *) send_data, size) == size) {
+            // Wait for all the echoed data to arrive
+            timer.start();
+            while ((recv_size < size) && (timer.read_ms() < ASYNC_TEST_WAIT_TIME)) {
+                if (*callback_triggered) {
+                    *callback_triggered = false;
+                    x = sock->recvfrom(&sender_address, (char *) recv_data + recv_size, size);
+                    if (x > 0) {
+                        recv_size += x;
+                    }
+                    tr_debug("%d byte(s) echoed back so far, %d to go.", recv_size, size - recv_size);
+                    TEST_ASSERT(strcmp(sender_address.get_ip_address(), host_address->get_ip_address()) == 0);
+                    TEST_ASSERT(sender_address.get_port() == host_address->get_port());
+                }
+                wait_ms(10);
+            }
+            timer.stop();
+            timer.reset();
+
+            // If everything arrived back, check it's the same as we sent
+            if (recv_size == size) {
+                z = memcmp(send_data, recv_data, size);
+                if (z != 0) {
+                    tr_debug("WARNING: mismatch, retrying");
+                    tr_debug("Sent %d, |%*.*s|", size, size, size, send_data);
+                    tr_debug("Rcvd %d, |%*.*s|", size, size, size, (char *) recv_data);
+                    // If things don't match, it could be due to data loss (this is UDP
+                    // you know...), so set recv_size to 0 to cause another try
+                    recv_size = 0;
+                }
+            }
+        }
+    }
+
+    TEST_ASSERT(recv_size == size);
+    TEST_ASSERT(!connection_has_gone_down);
+
+    free (recv_data);
+}
+
+// Send an entire TCP data buffer until done
+static int sendAll(TCPSocket *sock,  const char *data, int size)
+{
+    int x;
+    int count = 0;
+    Timer timer;
+
+    timer.start();
+    while ((count < size) && (timer.read_ms() < 10000)) {
+        x = sock->send(data + count, size - count);
+        if (x > 0) {
+            count += x;
+            tr_debug("%d byte(s) sent, %d left to send.", count, size - count);
+        }
+        wait_ms(10);
+    }
+    timer.stop();
+
+    return count;
+}
+
+// Do a TCP echo but using the asynchronous interface
+static void do_tcp_echo_async(TCPSocket *sock, int size, bool *callback_triggered)
+{
+    void * recv_data = malloc (size);
+    int recv_size = 0;
+    int x, y;
+    Timer timer;
+    TEST_ASSERT(recv_data != NULL);
+
+    *callback_triggered = false;
+    tr_debug("Echo testing TCP packet size %d byte(s) async.", size);
+    TEST_ASSERT (sendAll(sock, send_data, size) == size);
+
+    // Wait for all the echoed data to arrive
+    timer.start();
+    while ((recv_size < size) && (timer.read_ms() < ASYNC_TEST_WAIT_TIME)) {
+        if (*callback_triggered) {
+            *callback_triggered = false;
+            x = sock->recv((char *) recv_data + recv_size, size);
+            TEST_ASSERT(x > 0);
+            recv_size += x;
+            tr_debug("%d byte(s) echoed back so far, %d to go.", recv_size, size - recv_size);
+        }
+        wait_ms(10);
+    }
+    TEST_ASSERT(recv_size == size);
+    y = memcmp(send_data, recv_data, size);
+    if (y != 0) {
+        tr_debug("Sent %d, |%*.*s|", size, size, size, send_data);
+        tr_debug("Rcvd %d, |%*.*s|", size, size, size, (char *) recv_data);
+        TEST_ASSERT(false);
+    }
+    timer.stop();
+
+    TEST_ASSERT(!connection_has_gone_down);
+
+    free (recv_data);
+}
+#endif
+
+// Get NTP time from a socket
+static void do_ntp_sock (UDPSocket *sock, SocketAddress ntp_address)
+{
+    char ntp_values[48] = { 0 };
+    time_t timestamp = 0;
+    struct tm *localTime;
+    char timeString[25];
+    time_t TIME1970 = 2208988800U;
+    int len;
+    bool comms_done = false;
+
+    ntp_values[0] = '\x1b';
+
+    // Retry this a few times, don't want to fail due to a flaky link
+    for (unsigned int x = 0; !comms_done && (x < NUM_UDP_RETRIES); x++) {
+        sock->sendto(ntp_address, (void*) ntp_values, sizeof(ntp_values));
+        len = sock->recvfrom(&ntp_address, (void*) ntp_values, sizeof(ntp_values));
+        if (len > 0) {
+            comms_done = true;
+        }
+    }
+    TEST_ASSERT (comms_done);
+
+    tr_debug("UDP: %d byte(s) returned by NTP server.", len);
+    if (len >= 43) {
+        timestamp |= ((int) *(ntp_values + 40)) << 24;
+        timestamp |= ((int) *(ntp_values + 41)) << 16;
+        timestamp |= ((int) *(ntp_values + 42)) << 8;
+        timestamp |= ((int) *(ntp_values + 43));
+        timestamp -= TIME1970;
+        srand (timestamp);
+        tr_debug("srand() called");
+        localTime = localtime(&timestamp);
+        if (localTime) {
+            if (strftime(timeString, sizeof(timeString), "%a %b %d %H:%M:%S %Y", localTime) > 0) {
+                printf("NTP timestamp is %s.\n", timeString);
+            }
+        }
+    }
+}
+
+// Get NTP time
+static void do_ntp(UbloxATCellularInterfaceN2xx *interface)
+{
+    UDPSocket sock;
+    SocketAddress host_address;
+
+    TEST_ASSERT(sock.open(interface) == 0)
+
+    TEST_ASSERT(interface->gethostbyname(MBED_CONF_APP_NTP_SERVER, &host_address) == 0);
+    host_address.set_port(MBED_CONF_APP_NTP_PORT);
+
+    tr_debug("UDP: NIST server %s address: %s on port %d.", MBED_CONF_APP_NTP_SERVER,
+             host_address.get_ip_address(), host_address.get_port());
+
+    sock.set_timeout(10000);
+
+    do_ntp_sock(&sock, host_address);
+
+    sock.close();
+}
+
+// Use a connection, checking that it is good
+static void use_connection(UbloxATCellularInterfaceN2xx *interface)
+{
+    const char * ip_address = interface->get_ip_address();
+    const char * net_mask = interface->get_netmask();
+    const char * gateway = interface->get_gateway();
+
+    TEST_ASSERT(interface->is_connected());
+
+    TEST_ASSERT(ip_address != NULL);
+    tr_debug ("IP address %s.", ip_address);
+    TEST_ASSERT(net_mask == NULL);
+    tr_debug ("Net mask %s.", net_mask);
+    TEST_ASSERT(gateway != NULL);
+    tr_debug ("Gateway %s.", gateway);
+
+    do_ntp(interface);
+    TEST_ASSERT(!connection_has_gone_down);
+}
+
+// Drop a connection and check that it has dropped
+static void drop_connection(UbloxATCellularInterfaceN2xx *interface)
+{
+    TEST_ASSERT(interface->disconnect() == 0);
+    TEST_ASSERT(connection_has_gone_down);
+    connection_has_gone_down = false;
+    TEST_ASSERT(!interface->is_connected());
+}
+
+// ----------------------------------------------------------------
+// TESTS
+// ----------------------------------------------------------------
+
+// Call srand() using the NTP server
+void test_set_randomise() {
+    UDPSocket sock;
+    SocketAddress host_address;
+
+    tr_debug("Starting connect()...");
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    do_ntp(interface);
+    TEST_ASSERT(!connection_has_gone_down);
+    drop_connection(interface);
+}
+
+#ifdef MBED_CONF_APP_ECHO_SERVER
+
+// Test UDP data exchange
+void test_udp_echo() {
+    UDPSocket sock;
+    SocketAddress host_address;
+    SocketAddress local_address;
+    int x;
+    int size;
+    
+    interface->SendAT("AT+NSOCR=DGRAM, 17, 10000");
+    interface->SendAT("AT+NSOST=0,10.10.10.10,7,200,1122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900");
+
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+
+    TEST_ASSERT(interface->gethostbyname(MBED_CONF_APP_ECHO_SERVER, &host_address) == 0);
+    host_address.set_port(MBED_CONF_APP_ECHO_UDP_PORT);
+
+    tr_debug("UDP: Server %s address: %s on port %d.", MBED_CONF_APP_ECHO_SERVER,
+             host_address.get_ip_address(), host_address.get_port());
+
+    TEST_ASSERT(sock.open(interface) == 0)
+
+    sock.set_timeout(10000);
+
+    int sizes[] = { 1, 2, 5, 150, 160, 170, 180, 190, 200, 250 };
+    
+    // Test min, max, and some random sizes in-between
+    //do_udp_echo(&sock, &host_address, 1);
+    //do_udp_echo(&sock, &host_address, MBED_CONF_APP_UDP_MAX_PACKET_SIZE);
+    for (x = 0; x < 10; x++) {
+        do_udp_echo(&sock, &host_address, sizes[x]);
+    }
+    
+    // Test min, max, and some random sizes in-between
+    // do_udp_echo(&sock, &host_address, 1);
+    // do_udp_echo(&sock, &host_address, MBED_CONF_APP_UDP_MAX_PACKET_SIZE);
+    // for (x = 0; x < 10; x++) {
+        // size = (rand() % MBED_CONF_APP_UDP_MAX_PACKET_SIZE) + 1;
+        // size = fix(size, MBED_CONF_APP_UDP_MAX_PACKET_SIZE);
+        // do_udp_echo(&sock, &host_address, size);
+    // }
+
+    sock.close();
+    
+    drop_connection(interface);
+    tr_debug("%d UDP packets of size up to %d byte(s) echoed successfully.",
+             x, MBED_CONF_APP_UDP_MAX_PACKET_SIZE);
+}
+
+// Test many different sizes of UDP data arriving at once
+void  test_udp_echo_recv_sizes() {
+    UDPSocket sock;
+    SocketAddress host_address;
+    int x, y, z;
+    int size;
+    int tries = 0;
+    unsigned int offset;
+    char * recv_data;
+    bool packetLoss;
+    bool sendSuccess;
+    Timer timer;
+
+    interface->deinit();
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+
+    TEST_ASSERT(interface->gethostbyname(MBED_CONF_APP_ECHO_SERVER, &host_address) == 0);
+    host_address.set_port(MBED_CONF_APP_ECHO_UDP_PORT);
+
+    tr_debug("UDP: Server %s address: %s on port %d.", MBED_CONF_APP_ECHO_SERVER,
+             host_address.get_ip_address(), host_address.get_port());
+
+    TEST_ASSERT(sock.open(interface) == 0)
+
+    do {
+        tr_debug("--- UDP packet size test, test try %d, flushing input buffers", tries + 1);
+        // First of all, clear any junk from the socket
+        sock.set_timeout(1000);
+        recv_data = (char *) malloc (MBED_CONF_APP_UDP_MAX_PACKET_SIZE);
+        TEST_ASSERT(recv_data != NULL);
+        while (sock.recvfrom(&host_address, (void *) recv_data, MBED_CONF_APP_UDP_MAX_PACKET_SIZE) > 0) {
+            // Throw it away
+        }
+        free (recv_data);
+
+        sock.set_timeout(10000);
+
+        // Throw random sized UDP packets up...
+        x = 0;
+        offset = 0;
+        while (offset < sizeof (send_data)) {
+            size = (rand() % (MBED_CONF_APP_UDP_MAX_PACKET_SIZE / 2)) + 1;
+            size = fix(size, MBED_CONF_APP_UDP_MAX_PACKET_SIZE / 2);
+            if (offset + size > sizeof (send_data)) {
+                size = sizeof (send_data) - offset;
+            }
+            sendSuccess = false;
+            for (y = 0; !sendSuccess && (y < NUM_UDP_RETRIES); y++) {
+                tr_debug("Sending UDP packet number %d, size %d byte(s), send try %d.", x + 1, size, y + 1);
+                if (sock.sendto(host_address, (void *) (send_data + offset), size) == size) {
+                    sendSuccess = true;
+                    offset += size;
+                }
+            }
+            TEST_ASSERT(sendSuccess);
+            x++;
+        }
+        tr_debug("--- All UDP packets sent");
+
+        // ...and capture them all again afterwards
+        recv_data = (char *) malloc (sizeof (send_data));
+        TEST_ASSERT(recv_data != NULL);
+        memset (recv_data, 0, sizeof (send_data));
+        size = 0;
+        y = 0;
+        packetLoss = false;
+        timer.start();
+        while ((size < (int) sizeof (send_data)) && (timer.read_ms() < 10000)) {
+            y = sock.recvfrom(&host_address, (void *) (recv_data + size), sizeof (send_data) - size);
+            if (y > 0) {
+                size += y;
+            }
+        }
+        timer.stop();
+        timer.reset();
+        tr_debug(   "--- Either received everything back or timed out waiting");
+
+        // Check that we reassembled everything correctly
+        if (size == sizeof (send_data)) {
+            for (x = 0; ((*(recv_data + x) == *(send_data + x))) && (x < (int) sizeof (send_data)); x++) {
+            }
+            if (x != sizeof (send_data)) {
+                y = x - 5;
+                if (y < 0) {
+                    y = 0;
+                }
+                z = 10;
+                if (y + z > (int) sizeof (send_data)) {
+                    z = sizeof(send_data) - y;
+                }
+                tr_debug("   --- Difference at character %d (send \"%*.*s\", recv \"%*.*s\")",
+                         x + 1, z, z, send_data + y, z, z, recv_data + y);
+                packetLoss = true;
+            }
+        } else {
+            tr_debug("   --- %d bytes missing (%d bytes received when %d were expected))",
+                      sizeof (send_data) - size, size, sizeof (send_data));
+            packetLoss = true;
+        }
+        free (recv_data);
+        tries++;
+    } while (packetLoss && (tries < NUM_UDP_RETRIES));
+
+    TEST_ASSERT(!packetLoss);
+    TEST_ASSERT(!connection_has_gone_down);
+    sock.close();
+    drop_connection(interface);
+}
+
+// Test UDP data exchange via the asynchronous sigio() mechanism
+void test_udp_echo_async() {
+    UDPSocket sock;
+    SocketAddress host_address;
+    SocketAddress local_address;
+    bool callback_triggered = false;
+    int x;
+    int size;
+
+    interface->deinit();
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+
+    TEST_ASSERT(interface->gethostbyname(MBED_CONF_APP_ECHO_SERVER, &host_address) == 0);
+    host_address.set_port(MBED_CONF_APP_ECHO_UDP_PORT);
+
+    tr_debug("UDP: Server %s address: %s on port %d.", MBED_CONF_APP_ECHO_SERVER,
+             host_address.get_ip_address(), host_address.get_port());
+
+    TEST_ASSERT(sock.open(interface) == 0)
+
+    // Set up the async callback and set the timeout to zero
+    sock.sigio(callback(async_cb, &callback_triggered));
+    sock.set_timeout(0);
+
+    // Test min, max, and some random sizes in-between
+    // and this time allow the UDP packets to be fragmented
+    do_udp_echo_async(&sock, &host_address, 1, &callback_triggered);
+    do_udp_echo_async(&sock, &host_address, MBED_CONF_APP_UDP_MAX_FRAG_PACKET_SIZE,
+                      &callback_triggered);
+    for (x = 0; x < 10; x++) {
+        size = (rand() % MBED_CONF_APP_UDP_MAX_FRAG_PACKET_SIZE) + 1;
+        size = fix(size, MBED_CONF_APP_UDP_MAX_FRAG_PACKET_SIZE);
+        do_udp_echo_async(&sock, &host_address, size, &callback_triggered);
+    }
+
+    sock.close();
+
+    drop_connection(interface);
+
+    tr_debug("%d UDP packets of size up to %d byte(s) echoed asynchronously and successfully.",
+             x, MBED_CONF_APP_UDP_MAX_FRAG_PACKET_SIZE);
+}
+
+// Test many different sizes of TCP data arriving at once
+void  test_tcp_echo_recv_sizes() {
+    TCPSocket sock;
+    SocketAddress host_address;
+    int x, y, z;
+    int size;
+    unsigned int offset;
+    char * recv_data;
+    Timer timer;
+
+    interface->deinit();
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+
+    TEST_ASSERT(interface->gethostbyname(MBED_CONF_APP_ECHO_SERVER, &host_address) == 0);
+    host_address.set_port(MBED_CONF_APP_ECHO_TCP_PORT);
+
+    tr_debug("TCP: Server %s address: %s on port %d.", MBED_CONF_APP_ECHO_SERVER,
+             host_address.get_ip_address(), host_address.get_port());
+
+    TEST_ASSERT(sock.open(interface) == 0)
+
+    TEST_ASSERT(sock.connect(host_address) == 0);
+
+    sock.set_timeout(10000);
+
+    // Throw random sized TCP packets up...
+    x = 0;
+    offset = 0;
+    while (offset < sizeof (send_data)) {
+        size = (rand() % (MBED_CONF_APP_UDP_MAX_PACKET_SIZE / 2)) + 1;
+        size = fix(size, MBED_CONF_APP_UDP_MAX_PACKET_SIZE / 2);
+        if (offset + size > sizeof (send_data)) {
+            size = sizeof (send_data) - offset;
+        }
+        tr_debug("Sending TCP packet number %d, size %d byte(s).", x + 1, size);
+        TEST_ASSERT(sendAll(&sock, (send_data + offset), size) == size);
+        offset += size;
+        x++;
+    }
+
+    // ...and capture them all again afterwards
+    recv_data = (char *) malloc (sizeof (send_data));
+    TEST_ASSERT(recv_data != NULL);
+    memset (recv_data, 0, sizeof (send_data));
+    size = 0;
+    x = 0;
+    timer.start();
+    while ((size < (int) sizeof (send_data)) && (timer.read_ms() < 30000)) {
+        y = sock.recv((void *) (recv_data + size), sizeof (send_data) - size);
+        tr_debug("Received TCP packet number %d, size %d byte(s).", x, y);
+        size += y;
+        x++;
+    }
+    timer.stop();
+    timer.reset();
+
+    // Check that we reassembled everything correctly
+    for (x = 0; ((*(recv_data + x) == *(send_data + x))) && (x < (int) sizeof (send_data)); x++) {
+    }
+    if (x != sizeof (send_data)) {
+        y = x - 5;
+        if (y < 0) {
+            y = 0;
+        }
+        z = 10;
+        if (y + z > (int) sizeof (send_data)) {
+            z = sizeof(send_data) - y;
+        }
+        tr_debug("Difference at character %d (send \"%*.*s\", recv \"%*.*s\")",
+                 x + 1, z, z, send_data + y, z, z, recv_data + y);
+        TEST_ASSERT(false);
+    }
+    free (recv_data);
+
+    TEST_ASSERT(!connection_has_gone_down);
+    sock.close();
+    drop_connection(interface);
+}
+
+// Test TCP data exchange via the asynchronous sigio() mechanism
+void test_tcp_echo_async() {
+    TCPSocket sock;
+    SocketAddress host_address;
+    bool callback_triggered = false;
+    int x;
+    int size;
+
+    interface->deinit();
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+
+    TEST_ASSERT(interface->gethostbyname(MBED_CONF_APP_ECHO_SERVER, &host_address) == 0);
+    host_address.set_port(MBED_CONF_APP_ECHO_TCP_PORT);
+
+    tr_debug("TCP: Server %s address: %s on port %d.", MBED_CONF_APP_ECHO_SERVER,
+             host_address.get_ip_address(), host_address.get_port());
+
+    TEST_ASSERT(sock.open(interface) == 0)
+
+    // Set up the async callback and set the timeout to zero
+    sock.sigio(callback(async_cb, &callback_triggered));
+    sock.set_timeout(0);
+
+    TEST_ASSERT(sock.connect(host_address) == 0);
+    // Test min, max, and some random sizes in-between
+    do_tcp_echo_async(&sock, 1, &callback_triggered);
+    do_tcp_echo_async(&sock, MBED_CONF_APP_TCP_MAX_PACKET_SIZE, &callback_triggered);
+    for (x = 0; x < 10; x++) {
+        size = (rand() % MBED_CONF_APP_TCP_MAX_PACKET_SIZE) + 1;
+        size = fix(size, MBED_CONF_APP_TCP_MAX_PACKET_SIZE);
+        do_tcp_echo_async(&sock, size, &callback_triggered);
+    }
+
+    sock.close();
+
+    drop_connection(interface);
+
+    tr_debug("%d TCP packets of size up to %d byte(s) echoed asynchronously and successfully.",
+             x, MBED_CONF_APP_TCP_MAX_PACKET_SIZE);
+}
+#endif
+
+// Allocate max sockets
+void test_max_sockets() {
+    UDPSocket sock[MAX_NUM_SOCKETS];
+    UDPSocket sockNone;
+    SocketAddress host_address;
+
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+
+    TEST_ASSERT(interface->gethostbyname(MBED_CONF_APP_NTP_SERVER, &host_address) == 0);
+    host_address.set_port(MBED_CONF_APP_NTP_PORT);
+
+    // Open the first socket and use it
+    interface->set_LocalListenPort(10000);
+    TEST_ASSERT(sock[0].open(interface) == 0)
+    sock[0].set_timeout(10000);
+    do_ntp_sock(&sock[0], host_address);
+
+    // Check that we stop being able to get sockets at the max number
+    for (int x = 1; x < (int) (sizeof (sock) / sizeof (sock[0])); x++) {
+        interface->set_LocalListenPort(10000+x);
+        TEST_ASSERT(sock[x].open(interface) == 0)
+    }
+    TEST_ASSERT(sockNone.open(interface) < 0);
+
+    // Now use the last one
+    sock[sizeof (sock) / sizeof (sock[0]) - 1].set_timeout(10000);
+    do_ntp_sock(&sock[sizeof (sock) / sizeof (sock[0]) - 1], host_address);
+
+    // Close all of the sockets
+    for (int x = 0; x < (int) (sizeof (sock) / sizeof (sock[0])); x++) {
+        TEST_ASSERT(sock[x].close() == 0);
+    }
+
+    drop_connection(interface);
+}
+
+// Connect with credentials included in the connect request
+void test_connect_credentials() {
+
+    interface->deinit();
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+}
+
+// Test with credentials preset
+void test_connect_preset_credentials() {
+
+    interface->deinit();
+    TEST_ASSERT(interface->init(MBED_CONF_APP_DEFAULT_PIN));
+    interface->set_credentials(MBED_CONF_APP_APN, MBED_CONF_APP_USERNAME,
+                               MBED_CONF_APP_PASSWORD);
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+}
+
+// Test adding and using a SIM pin, then removing it, using the pending
+// mechanism where the change doesn't occur until connect() is called
+void test_check_sim_pin_pending() {
+
+    interface->deinit();
+
+    // Enable PIN checking (which will use the current PIN)
+    // and also flag that the PIN should be changed to MBED_CONF_APP_ALT_PIN,
+    // then try connecting
+    interface->set_sim_pin_check(true);
+    interface->set_new_sim_pin(MBED_CONF_APP_ALT_PIN);
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+    interface->deinit();
+
+    // Now change the PIN back to what it was before
+    interface->set_new_sim_pin(MBED_CONF_APP_DEFAULT_PIN);
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_ALT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+    interface->deinit();
+
+    // Check that it was changed back, and this time
+    // use the other way of entering the PIN
+    interface->set_sim_pin(MBED_CONF_APP_DEFAULT_PIN);
+    TEST_ASSERT(interface->connect(NULL, MBED_CONF_APP_APN, MBED_CONF_APP_USERNAME,
+                                   MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+    interface->deinit();
+
+    // Remove PIN checking again and check that it no
+    // longer matters what the PIN is
+    interface->set_sim_pin_check(false);
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+    interface->deinit();
+    TEST_ASSERT(interface->init(NULL));
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_INCORRECT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+
+    // Put the SIM pin back to the correct value for any subsequent tests
+    interface->set_sim_pin(MBED_CONF_APP_DEFAULT_PIN);
+}
+
+// Test adding and using a SIM pin, then removing it, using the immediate
+// mechanism
+void test_check_sim_pin_immediate() {
+
+    interface->deinit();
+    interface->connection_status_cb(connection_down_cb);
+
+    // Enable PIN checking (which will use the current PIN), change
+    // the PIN to MBED_CONF_APP_ALT_PIN, then try connecting after powering on and
+    // off the modem
+    interface->set_sim_pin_check(true, true, MBED_CONF_APP_DEFAULT_PIN);
+    interface->set_new_sim_pin(MBED_CONF_APP_ALT_PIN, true);
+    interface->deinit();
+    TEST_ASSERT(interface->init(NULL));
+    TEST_ASSERT(interface->connect(MBED_CONF_APP_ALT_PIN, MBED_CONF_APP_APN,
+                                   MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+
+    interface->connection_status_cb(connection_down_cb);
+
+    // Now change the PIN back to what it was before
+    interface->set_new_sim_pin(MBED_CONF_APP_DEFAULT_PIN, true);
+    interface->deinit();
+    interface->set_sim_pin(MBED_CONF_APP_DEFAULT_PIN);
+    TEST_ASSERT(interface->init(NULL));
+    TEST_ASSERT(interface->connect(NULL, MBED_CONF_APP_APN, MBED_CONF_APP_USERNAME,
+                                   MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+
+    interface->connection_status_cb(connection_down_cb);
+
+    // Remove PIN checking again and check that it no
+    // longer matters what the PIN is
+    interface->set_sim_pin_check(false, true);
+    interface->deinit();
+    TEST_ASSERT(interface->init(MBED_CONF_APP_INCORRECT_PIN));
+    TEST_ASSERT(interface->connect(NULL, MBED_CONF_APP_APN, MBED_CONF_APP_USERNAME,
+                                   MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(interface);
+    drop_connection(interface);
+
+    // Put the SIM pin back to the correct value for any subsequent tests
+    interface->set_sim_pin(MBED_CONF_APP_DEFAULT_PIN);
+}
+
+// Test being able to connect with a local instance of the interface
+// NOTE: since this local instance will fiddle with bits of HW that the
+// static instance thought it owned, the static instance will no longer
+// work afterwards, hence this must be run as the last test in the list
+void test_connect_local_instance_last_test() {
+
+    UbloxATCellularInterfaceN2xx *pLocalInterface = NULL;
+
+    pLocalInterface = new UbloxATCellularInterfaceN2xx(MDMTXD, MDMRXD,
+                                                   MBED_CONF_UBLOX_CELL_N2XX_BAUD_RATE,
+                                                   MBED_CONF_APP_DEBUG_ON);
+    pLocalInterface->connection_status_cb(connection_down_cb);
+
+    TEST_ASSERT(pLocalInterface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                         MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(pLocalInterface);
+    drop_connection(pLocalInterface);
+    delete pLocalInterface;
+
+    pLocalInterface = new UbloxATCellularInterfaceN2xx(MDMTXD, MDMRXD,
+                                                   MBED_CONF_UBLOX_CELL_N2XX_BAUD_RATE,
+                                                   MBED_CONF_APP_DEBUG_ON);
+    pLocalInterface->connection_status_cb(connection_down_cb);
+
+    TEST_ASSERT(pLocalInterface->connect(MBED_CONF_APP_DEFAULT_PIN, MBED_CONF_APP_APN,
+                                         MBED_CONF_APP_USERNAME, MBED_CONF_APP_PASSWORD) == 0);
+    use_connection(pLocalInterface);
+    drop_connection(pLocalInterface);
+    delete pLocalInterface;
+}
+
+// ----------------------------------------------------------------
+// TEST ENVIRONMENT
+// ----------------------------------------------------------------
+
+// Setup the test environment
+utest::v1::status_t test_setup(const size_t number_of_cases) {
+    // Setup Greentea with a timeout
+    GREENTEA_SETUP(960, "default_auto");
+    return verbose_test_setup_handler(number_of_cases);
+}
+
+// IMPORTANT!!! if you make a change to the tests here you should
+// check whether the same change should be made to the tests under
+// the PPP interface.
+
+// Test cases
+Case cases[] = {
+    Case("Set randomise", test_set_randomise),
+#ifdef MBED_CONF_APP_ECHO_SERVER
+    Case("UDP echo test", test_udp_echo),
+# ifndef TARGET_UBLOX_C027 // Not enough RAM on little 'ole C027 to run this test
+    Case("UDP recv sizes", test_udp_echo_recv_sizes),
+# endif
+    Case("UDP async echo test", test_udp_echo_async),
+# ifndef TARGET_UBLOX_C027 // Not enough RAM on little 'ole C027 to run this test
+    Case("TCP recv sizes", test_tcp_echo_recv_sizes),
+# endif
+    Case("TCP async echo test", test_tcp_echo_async),
+# endif
+#ifndef TARGET_UBLOX_C027 // Not enough RAM on little 'ole C027 to run this test
+    Case("Alloc max sockets", test_max_sockets),
+#endif
+    Case("Connect with credentials", test_connect_credentials),
+    Case("Connect with preset credentials", test_connect_preset_credentials),
+#if MBED_CONF_APP_RUN_SIM_PIN_CHANGE_TESTS
+    Case("Check SIM pin, pending", test_check_sim_pin_pending),
+    Case("Check SIM pin, immediate", test_check_sim_pin_immediate),
+#endif
+#ifndef TARGET_UBLOX_C027 // Not enough RAM on little 'ole C027 for this
+    Case("Connect using local instance, must be last test", test_connect_local_instance_last_test)
+#endif
+};
+
+Specification specification(test_setup, cases);
+
+// ----------------------------------------------------------------
+// MAIN
+// ----------------------------------------------------------------
+
+int main() {
+
+#ifdef FEATURE_COMMON_PAL
+    mbed_trace_init();
+
+    mbed_trace_mutex_wait_function_set(lock);
+    mbed_trace_mutex_release_function_set(unlock);
+#endif
+
+    interface = new UbloxATCellularInterfaceN2xx(MDMTXD, MDMRXD,
+                                    MBED_CONF_UBLOX_CELL_N2XX_BAUD_RATE,
+                                    MBED_CONF_APP_DEBUG_ON);
+
+    interface->connection_status_cb(connection_down_cb);
+
+    tr_debug("Sending large AT command: 150bytes SendTo");    
+    interface->SendAT("AT+NSOST=0,10.10.10.10,7,150,112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900");
+    tr_debug("Sending large AT command: 200bytes SendTo");    
+    interface->SendAT("AT+NSOST=0,10.10.10.10,7,200,1122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900112233445566778899001122334455667788990011223344556677889900");
+    
+    // Run tests
+    return !Harness::run(specification);
+}
+
+// End Of File
+