Vandan Patel / ntp-client

Dependents:   UDP_RoundTripDelay_OS6_H743ZI advancedIO_1wifiMessing_copy advancedIO_Assignment_Program UDP_RoundTripDelay_OS6_K64F

Revision:
0:d4145a1a189a
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/NTPClient.cpp	Thu Sep 10 00:31:53 2020 +0000
@@ -0,0 +1,90 @@
+/* Copyright (c) 2019 ARM, Arm Limited and affiliates.
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "ntp-client/NTPClient.h"
+#include "mbed.h"
+
+NTPClient::NTPClient(NetworkInterface *interface)
+    : iface(interface), nist_server_address(NTP_DEFULT_NIST_SERVER_ADDRESS), nist_server_port(NTP_DEFULT_NIST_SERVER_PORT) {
+}
+
+void NTPClient::set_server(const char* server, int port) {
+    nist_server_address = server;
+    nist_server_port = port;
+}
+
+time_t NTPClient::get_timestamp(int timeout) {
+    const time_t TIME1970 = (time_t)2208988800UL;
+    int ntp_send_values[12] = {0};
+    int ntp_recv_values[12] = {0};
+
+    SocketAddress nist;
+
+    if (iface) {
+        int ret_gethostbyname = iface->gethostbyname(nist_server_address, &nist);
+
+        if (ret_gethostbyname < 0) {
+            // Network error on DNS lookup
+            return ret_gethostbyname;
+        }
+
+        nist.set_port(nist_server_port);
+
+        memset(ntp_send_values, 0x00, sizeof(ntp_send_values));
+        ntp_send_values[0] = '\x1b';
+
+        memset(ntp_recv_values, 0x00, sizeof(ntp_recv_values));
+
+        UDPSocket sock;
+        sock.open(iface);
+        sock.set_timeout(timeout);
+
+        sock.sendto(nist, (void*)ntp_send_values, sizeof(ntp_send_values));
+
+        SocketAddress source;
+        const int n = sock.recvfrom(&source, (void*)ntp_recv_values, sizeof(ntp_recv_values));
+
+        if (n > 10) {
+            return ntohl(ntp_recv_values[10]) - TIME1970;
+
+        } else {
+            if (n < 0) {
+                // Network error
+                return n;
+
+            } else {
+                // No or partial data returned
+                return -1;
+            }
+        }
+
+    } else {
+        // No network interface
+        return -2;
+    }
+}
+
+void NTPClient::network(NetworkInterface *interface) {
+    iface = interface;
+}
+
+uint32_t NTPClient::ntohl(uint32_t x) {
+    uint32_t ret = (x & 0xff) << 24;
+    ret |= (x & 0xff00) << 8;
+    ret |= (x & 0xff0000UL) >> 8;
+    ret |= (x & 0xff000000UL) >> 24;
+    return ret;
+}