|
| 1 | +/* |
| 2 | + * Udp.cpp: Library to send/receive UDP packets. |
| 3 | + * |
| 4 | + * NOTE: UDP is fast, but has some important limitations (thanks to Warren Gray for mentioning these) |
| 5 | + * 1) UDP does not guarantee the order in which assembled UDP packets are received. This |
| 6 | + * might not happen often in practice, but in larger network topologies, a UDP |
| 7 | + * packet can be received out of sequence. |
| 8 | + * 2) UDP does not guard against lost packets - so packets *can* disappear without the sender being |
| 9 | + * aware of it. Again, this may not be a concern in practice on small local networks. |
| 10 | + * For more information, see http://www.cafeaulait.org/course/week12/35.html |
| 11 | + * |
| 12 | + * MIT License: |
| 13 | + * Copyright (c) 2008 Bjoern Hartmann |
| 14 | + * Permission is hereby granted, free of charge, to any person obtaining a copy |
| 15 | + * of this software and associated documentation files (the "Software"), to deal |
| 16 | + * in the Software without restriction, including without limitation the rights |
| 17 | + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| 18 | + * copies of the Software, and to permit persons to whom the Software is |
| 19 | + * furnished to do so, subject to the following conditions: |
| 20 | + * |
| 21 | + * The above copyright notice and this permission notice shall be included in |
| 22 | + * all copies or substantial portions of the Software. |
| 23 | + * |
| 24 | + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| 25 | + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 26 | + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| 27 | + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 28 | + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| 29 | + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN |
| 30 | + * THE SOFTWARE. |
| 31 | + * |
| 32 | + * bjoern@cs.stanford.edu 12/30/2008 |
| 33 | +*/ |
| 34 | + |
| 35 | +#pragma once |
| 36 | + |
| 37 | +#include"Stream.h" |
| 38 | +#include"IPAddress.h" |
| 39 | + |
| 40 | +classUDP :publicStream { |
| 41 | + |
| 42 | +public: |
| 43 | +virtualuint8_tbegin(uint16_t) =0;// initialize, start listening on specified port. Returns 1 if successful, 0 if there are no sockets available to use |
| 44 | +virtualvoidstop() =0;// Finish with the UDP socket |
| 45 | + |
| 46 | +// Sending UDP packets |
| 47 | + |
| 48 | +// Start building up a packet to send to the remote host specific in ip and port |
| 49 | +// Returns 1 if successful, 0 if there was a problem with the supplied IP address or port |
| 50 | +virtualintbeginPacket(IPAddress ip,uint16_t port) =0; |
| 51 | +// Start building up a packet to send to the remote host specific in host and port |
| 52 | +// Returns 1 if successful, 0 if there was a problem resolving the hostname or port |
| 53 | +virtualintbeginPacket(constchar *host,uint16_t port) =0; |
| 54 | +// Finish off this packet and send it |
| 55 | +// Returns 1 if the packet was sent successfully, 0 if there was an error |
| 56 | +virtualintendPacket() =0; |
| 57 | +// Write a single byte into the packet |
| 58 | +virtualsize_twrite(uint8_t) =0; |
| 59 | +// Write size bytes from buffer into the packet |
| 60 | +virtualsize_twrite(constuint8_t *buffer,size_t size) =0; |
| 61 | + |
| 62 | +// Start processing the next available incoming packet |
| 63 | +// Returns the size of the packet in bytes, or 0 if no packets are available |
| 64 | +virtualintparsePacket() =0; |
| 65 | +// Number of bytes remaining in the current packet |
| 66 | +virtualintavailable() =0; |
| 67 | +// Read a single byte from the current packet |
| 68 | +virtualintread() =0; |
| 69 | +// Read up to len bytes from the current packet and place them into buffer |
| 70 | +// Returns the number of bytes read, or 0 if none are available |
| 71 | +virtualintread(unsignedchar* buffer,size_t len) =0; |
| 72 | +// Read up to len characters from the current packet and place them into buffer |
| 73 | +// Returns the number of characters read, or 0 if none are available |
| 74 | +virtualintread(char* buffer,size_t len) =0; |
| 75 | +// Return the next byte from the current packet without moving on to the next byte |
| 76 | +virtualintpeek() =0; |
| 77 | +virtualvoidflush() =0;// Finish reading the current packet |
| 78 | + |
| 79 | +// Return the IP address of the host who sent the current incoming packet |
| 80 | +virtual IPAddressremoteIP() =0; |
| 81 | +// Return the port of the host who sent the current incoming packet |
| 82 | +virtualuint16_tremotePort() =0; |
| 83 | +protected: |
| 84 | +uint8_t*rawIPAddress(IPAddress& addr) {return addr.raw_address(); }; |
| 85 | +}; |
| 86 | + |