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Diffstat (limited to 'libraries/Ethernet/EthernetUdp.h')
-rw-r--r-- | libraries/Ethernet/EthernetUdp.h | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/libraries/Ethernet/EthernetUdp.h b/libraries/Ethernet/EthernetUdp.h new file mode 100644 index 0000000..8a6b7ab --- /dev/null +++ b/libraries/Ethernet/EthernetUdp.h @@ -0,0 +1,99 @@ +/* + * Udp.cpp: Library to send/receive UDP packets with the Arduino ethernet shield. + * This version only offers minimal wrapping of socket.c/socket.h + * Drop Udp.h/.cpp into the Ethernet library directory at hardware/libraries/Ethernet/ + * + * 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 ethernetudp_h +#define ethernetudp_h + +#include <Udp.h> + +#define UDP_TX_PACKET_MAX_SIZE 24 + +class EthernetUDP : public UDP { +private: + uint8_t _sock; // socket ID for Wiz5100 + uint16_t _port; // local port to listen on + IPAddress _remoteIP; // remote IP address for the incoming packet whilst it's being processed + uint16_t _remotePort; // remote port for the incoming packet whilst it's being processed + uint16_t _offset; // offset into the packet being sent + uint16_t _remaining; // remaining bytes of incoming packet yet to be processed + +public: + EthernetUDP(); // Constructor + virtual uint8_t begin(uint16_t); // initialize, start listening on specified port. Returns 1 if successful, 0 if there are no sockets available to use + virtual void stop(); // 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); + // 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); + // Finish off this packet and send it + // Returns 1 if the packet was sent successfully, 0 if there was an error + virtual int endPacket(); + // Write a single byte into the packet + virtual size_t write(uint8_t); + // Write size bytes from buffer into the packet + virtual size_t write(const uint8_t *buffer, size_t size); + + using Print::write; + + // 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(); + // Number of bytes remaining in the current packet + virtual int available(); + // Read a single byte from the current packet + virtual int read(); + // 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); + // 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) { return read((unsigned char*)buffer, len); }; + // Return the next byte from the current packet without moving on to the next byte + virtual int peek(); + virtual void flush(); // Finish reading the current packet + + // Return the IP address of the host who sent the current incoming packet + virtual IPAddress remoteIP() { return _remoteIP; }; + // Return the port of the host who sent the current incoming packet + virtual uint16_t remotePort() { return _remotePort; }; +}; + +#endif |