Diff: NTPClient/NTPClient.h

Revision:

21:f3818e2e0370

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/NTPClient/NTPClient.h	Tue Nov 21 17:04:12 2017 +0000
@@ -0,0 +1,212 @@
+/* NTPClient.h */
+/* Copyright (C) 2012 mbed.org, MIT License
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
+ * and associated documentation files (the "Software"), to deal in the Software without restriction,
+ * including without limitation the rights to use, copy, modify, merge, publish, distribute,
+ * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all copies or
+ * substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
+ * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+ * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ */
+
+/** \file
+NTP Client header file
+*/
+
+#ifndef NTPCLIENT_H_
+#define NTPCLIENT_H_
+
+#include <cstdint>
+
+using std::uint8_t;
+using std::uint16_t;
+using std::uint32_t;
+
+#include "EthernetInterface.h"
+#include "UDPSocket.h"
+
+#define NTP_DEFAULT_PORT 123
+#define NTP_DEFAULT_TIMEOUT 4000
+
+///NTP client results
+enum NTPResult {
+    NTP_OK = 0,     ///<Success
+    NTP_DNS,        ///<Could not resolve name
+    NTP_PRTCL,      ///<Protocol error
+    NTP_TIMEOUT,    ///<Connection timeout
+    NTP_CONN,       ///<Connection error
+};
+
+/** NTP Client to update the mbed's RTC using a remote time server
+*
+*/
+class NTPClient
+{
+public:
+    /**
+    Instantiate the NTP client
+    * @param[in] net is a pointer to the EthernetInterface
+    */
+    NTPClient(EthernetInterface * net = NULL);
+
+    /**Get current time (blocking)
+    Update the time using the server host
+    Blocks until completion
+    @param[in] host NTP server IPv4 address or hostname (will be resolved via DNS)
+    @param[in] port port to use; defaults to 123
+    @param[in] timeout waiting timeout in ms (osWaitForever for blocking function, not recommended)
+    @return 0 on success, NTP error code (<0) on failure
+    */
+    NTPResult setTime(const char* host, uint16_t port = NTP_DEFAULT_PORT, uint32_t timeout = NTP_DEFAULT_TIMEOUT); //Blocking
+
+private:
+    EthernetInterface * net;
+    
+    /// The NTP Packet, as defined in RFC 4330 for Simple NTP
+    ///
+    /// @caution We are in Little Endian locally, and Big Endian at the Network
+    ///         so some transformations are required.
+    ///
+    struct NTPPacket { 
+        /// Mode is a 3-bit number indicating the protocol mode
+        ///
+        /// values
+        ///     - 0 = reserved, 
+        ///     - 1 = symmetric active
+        ///     - 2 = symmetric passive
+        ///     - 3 = client
+        ///     - 4 = server
+        ///     - 5 = broadcast
+        ///     - 6 = reserved for NTP control message
+        ///     - 7 = reserved for private use
+        ///
+        unsigned mode : 3;
+        
+        /// Version Number
+        ///
+        /// The current version number for NTP/SNTP is 4
+        ///
+        unsigned vn : 3;    
+
+        /// Leap Indicator
+        ///
+        /// values
+        ///     - 0 = no warning, 
+        ///     - 1 = last min had 61s, 
+        ///     - 2 = last min had 59s, 
+        ///     - 3 = alarm - clock not in sync
+        ///
+        unsigned li : 2;    
+
+        /// This is indicates the stratum
+        ///
+        /// values
+        ///     - 0 = kiss-o'-death
+        ///     - 1 = primary reference
+        ///     - 2-15 = secondary reference
+        ///     - 16-255 = reserved
+        ///
+        uint8_t stratum;
+        
+        /// Poll interval
+        ///
+        /// This is an exponent of two, where the resulting value is the max
+        /// interval between successive messages in seconds.
+        ///
+        uint8_t poll;
+        
+        /// Precision of the clock
+        ///
+        /// This is an eight-bit signed integer used as an exponent of
+        /// two, where the resulting value is the precision of the system clock
+        /// in seconds.  This field is significant only in server messages, where
+        /// the values range from -6 for mains-frequency clocks to -20 for
+        /// microsecond clocks found in some workstations.
+        ///
+        int8_t precision;
+        //32 bits header
+
+        /// Root Delay
+        /// 
+        /// This is a 32-bit signed fixed-point number indicating the
+        /// total roundtrip delay to the primary reference source, in seconds
+        /// with the fraction point between bits 15 and 16.  Note that this
+        /// variable can take on both positive and negative values, depending on
+        /// the relative time and frequency offsets.  This field is significant
+        /// only in server messages, where the values range from negative values
+        /// of a few milliseconds to positive values of several hundred
+        /// milliseconds.
+        ///
+        int32_t rootDelay;
+        
+        /// Root Dispersion: This is a 32-bit unsigned fixed-point number
+        /// indicating the maximum error due to the clock frequency tolerance, in
+        /// seconds with the fraction point between bits 15 and 16.  This field
+        /// is significant only in server messages, where the values range from
+        /// zero to several hundred milliseconds.
+        ///
+        uint32_t rootDispersion;
+        
+        /// This idenfies a particular clock source
+        ///
+        uint32_t refId;
+
+        /// Reference Timestamp identified when the clock was last set.
+        /// 
+        /// It is a 64-bit value, this is in whole seconds
+        ///
+        uint32_t refTm_s;
+        /// Reference Timestamp identified when the clock was last set.
+        /// 
+        /// It is a 64-bit value, this is in fractions of a second
+        ///
+        uint32_t refTm_f;
+
+        /// Originate Timestamp identified when the request departed the client.
+        /// 
+        /// It is a 64-bit value, this is in whole seconds
+        ///
+        uint32_t origTm_s;
+        /// Originate Timestamp identified when the request departed the client.
+        /// 
+        /// It is a 64-bit value, this is in fractions of a second
+        ///
+        uint32_t origTm_f;
+
+        /// Receive Timestamp identified when the request arrived at the server.
+        /// 
+        /// It is a 64-bit value, this is in whole seconds
+        ///
+        uint32_t rxTm_s;
+        /// Receive Timestamp identified when the request arrived at the server.
+        /// 
+        /// It is a 64-bit value, this is in fractions of a second
+        ///
+        uint32_t rxTm_f;
+
+        /// Transmit Timestamp identified when the request departed the client/server.
+        /// 
+        /// It is a 64-bit value, this is in whole seconds
+        ///
+        uint32_t txTm_s;
+        /// Transmit Timestamp identified when the request departed the client/server.
+        /// 
+        /// It is a 64-bit value, this is in fractions of a second
+        ///
+        uint32_t txTm_f;
+    } __attribute__ ((packed));
+
+    UDPSocket m_sock;
+};
+
+
+#endif /* NTPCLIENT_H_ */