Diff: utility/Udp.h

Revision:

9:a156d3de5647

Child:

14:7648334eb41b

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/utility/Udp.h	Tue Aug 27 15:01:10 2019 +0000
@@ -0,0 +1,95 @@
+/*
+ *  Udp.cpp: Library to send/receive UDP packets.
+ *
+ * NOTE: UDP is fast, but has some important limitations (thanks to Warren Gray for mentioning these)
+ * 1) UDP does not guarantee the order in which assembled UDP packets are received. This
+ * might not happen often in practice, but in larger network topologies, a UDP
+ * packet can be received out of sequence. 
+ * 2) UDP does not guard against lost packets - so packets *can* disappear without the sender being
+ * aware of it. Again, this may not be a concern in practice on small local networks.
+ * For more information, see http://www.cafeaulait.org/course/week12/35.html
+ *
+ * MIT License:
+ * Copyright (c) 2008 Bjoern Hartmann
+ * 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.
+ *
+ * bjoern@cs.stanford.edu 12/30/2008
+ */
+#ifndef udp_h
+#define udp_h
+
+#include "mbed.h"
+#include "IpAddress.h"
+
+class   Udp
+{
+public:
+    virtual uint8_t     begin(uint16_t) = 0;    // initialize, start listening on specified port. Returns 1 if successful, 0 if there are no sockets available to use
+    virtual void        stop(void) = 0;         // Finish with the UDP socket
+
+    // Sending UDP packets
+    // Start building up a packet to send to the remote host specific in ip and port
+    // Returns 1 if successful, 0 if there was a problem with the supplied IP address or port
+    virtual int         beginPacket(IpAddress ip, uint16_t port) = 0;
+
+    // Start building up a packet to send to the remote host specific in host and port
+    // Returns 1 if successful, 0 if there was a problem resolving the hostname or port
+    virtual int         beginPacket(const char* host, uint16_t port) = 0;
+
+    // Finish off this packet and send it
+    // Returns 1 if the packet was sent successfully, 0 if there was an error
+    virtual int         endPacket(void) = 0;
+
+    // Write a single byte into the packet
+    virtual size_t      write(uint8_t) = 0;
+
+    // Write size bytes from buffer into the packet
+    virtual size_t      write(const uint8_t* buffer, size_t size) = 0;
+
+    // Start processing the next available incoming packet
+    // Returns the size of the packet in bytes, or 0 if no packets are available
+    virtual int         parsePacket(void) = 0;
+
+    // Number of bytes remaining in the current packet
+    virtual int         available(void) = 0;
+
+    // Read a single byte from the current packet
+    virtual int         read(void) = 0;
+
+    // Read up to len bytes from the current packet and place them into buffer
+    // Returns the number of bytes read, or 0 if none are available
+    virtual int         read(unsigned char* buffer, size_t len) = 0;
+
+    // Read up to len characters from the current packet and place them into buffer
+    // Returns the number of characters read, or 0 if none are available
+    virtual int         read(char* buffer, size_t len) = 0;
+
+    // Return the next byte from the current packet without moving on to the next byte
+    virtual int         peek(void) = 0;
+    virtual void        flush(void) = 0;        // Finish reading the current packet
+
+    // Return the IP address of the host who sent the current incoming packet
+    virtual IpAddress   remoteIP(void) = 0;
+
+    // Return the port of the host who sent the current incoming packet
+    virtual uint16_t    remotePort(void) = 0;
+protected:
+    uint8_t*    rawIPAddress(IpAddress& addr)   { return addr.rawAddress(); };
+};
+#endif