You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
137 lines
4.8 KiB
C++
137 lines
4.8 KiB
C++
/*
|
|
* 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/
|
|
*
|
|
* 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
|
|
*/
|
|
|
|
#include "w5100.h"
|
|
#include "socket.h"
|
|
#include "Ethernet.h"
|
|
#include "Udp.h"
|
|
|
|
/* Start UDP socket, listening at local port PORT */
|
|
void UdpClass::begin(uint16_t port) {
|
|
_port = port;
|
|
_sock = 0; //TODO: should not be hardcoded
|
|
socket(_sock, SnMR::UDP, _port, 0);
|
|
}
|
|
|
|
/* Send packet contained in buf of length len to peer at specified ip, and port */
|
|
/* Use this function to transmit binary data that might contain 0x00 bytes*/
|
|
/* This function returns sent data size for success else -1. */
|
|
uint16_t UdpClass::sendPacket(uint8_t * buf, uint16_t len, uint8_t * ip, uint16_t port){
|
|
return sendto(_sock,(const uint8_t *)buf,len,ip,port);
|
|
}
|
|
|
|
/* Send zero-terminated string str as packet to peer at specified ip, and port */
|
|
/* This function returns sent data size for success else -1. */
|
|
uint16_t UdpClass::sendPacket(const char str[], uint8_t * ip, uint16_t port){
|
|
// compute strlen
|
|
const char *s;
|
|
for(s = str; *s; ++s);
|
|
uint16_t len = (s-str);
|
|
// send packet
|
|
return sendto(_sock,(const uint8_t *)str,len,ip,port);
|
|
}
|
|
/* Is data available in rx buffer? Returns 0 if no, number of available bytes if yes.
|
|
* returned value includes 8 byte UDP header!*/
|
|
int UdpClass::available() {
|
|
return W5100.getRXReceivedSize(_sock);
|
|
}
|
|
|
|
|
|
/* Read a received packet into buffer buf (which is of maximum length len); */
|
|
/* store calling ip and port as well. Call available() to make sure data is ready first. */
|
|
/* NOTE: I don't believe len is ever checked in implementation of recvfrom(),*/
|
|
/* so it's easy to overflow buffer. so we check and truncate. */
|
|
/* returns number of bytes read, or negative number of bytes we would have needed if we truncated */
|
|
int UdpClass::readPacket(uint8_t * buf, uint16_t bufLen, uint8_t *ip, uint16_t *port) {
|
|
int packetLen = available()-8; //skip UDP header;
|
|
if(packetLen < 0 ) return 0; // no real data here
|
|
if(packetLen > (int)bufLen) {
|
|
//packet is too large - truncate
|
|
//HACK - hand-parse the UDP packet using TCP recv method
|
|
uint8_t tmpBuf[8];
|
|
int i;
|
|
//read 8 header bytes and get IP and port from it
|
|
recv(_sock,tmpBuf,8);
|
|
ip[0] = tmpBuf[0];
|
|
ip[1] = tmpBuf[1];
|
|
ip[2] = tmpBuf[2];
|
|
ip[3] = tmpBuf[3];
|
|
*port = tmpBuf[4];
|
|
*port = (*port << 8) + tmpBuf[5];
|
|
|
|
//now copy first (bufLen) bytes into buf
|
|
for(i=0;i<(int)bufLen;i++) {
|
|
recv(_sock,tmpBuf,1);
|
|
buf[i]=tmpBuf[0];
|
|
}
|
|
|
|
//and just read the rest byte by byte and throw it away
|
|
while(available()) {
|
|
recv(_sock,tmpBuf,1);
|
|
}
|
|
|
|
return (-1*packetLen);
|
|
|
|
//ALTERNATIVE: requires stdlib - takes a bunch of space
|
|
/*//create new buffer and read everything into it
|
|
uint8_t * tmpBuf = (uint8_t *)malloc(packetLen);
|
|
recvfrom(_sock,tmpBuf,packetLen,ip,port);
|
|
if(!tmpBuf) return 0; //couldn't allocate
|
|
// copy first bufLen bytes
|
|
for(unsigned int i=0; i<bufLen; i++) {
|
|
buf[i]=tmpBuf[i];
|
|
}
|
|
//free temp buffer
|
|
free(tmpBuf);
|
|
*/
|
|
|
|
|
|
}
|
|
return recvfrom(_sock,buf,bufLen,ip,port);
|
|
}
|
|
|
|
/* Read a received packet, throw away peer's ip and port. See note above. */
|
|
int UdpClass::readPacket(uint8_t * buf, uint16_t len) {
|
|
uint8_t ip[4];
|
|
uint16_t port[1];
|
|
return recvfrom(_sock,buf,len,ip,port);
|
|
}
|
|
|
|
int UdpClass::readPacket(char * buf, uint16_t bufLen, uint8_t *ip, uint16_t &port) {
|
|
uint16_t myPort;
|
|
uint16_t ret = readPacket( (byte*)buf, bufLen, ip, &myPort);
|
|
port = myPort;
|
|
return ret;
|
|
}
|
|
|
|
|
|
|
|
|
|
/* Create one global object */
|
|
UdpClass Udp;
|