Control a robot over the internet using UDP and a Ethernet interface.
Dependencies: EthernetInterface Motor TextLCD mbed-rtos mbed Socket lwip-eth lwip-sys lwip
Diff: EthernetInterface/Socket/UDPSocket.cpp
- Revision:
- 0:1496281373a5
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/EthernetInterface/Socket/UDPSocket.cpp Thu Oct 17 13:26:38 2013 +0000 @@ -0,0 +1,94 @@ +/* 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. + */ + +#include "Socket/UDPSocket.h" + +#include <cstring> + +using std::memset; + +UDPSocket::UDPSocket() { +} + +int UDPSocket::init(void) { + return init_socket(SOCK_DGRAM); +} + +// Server initialization +int UDPSocket::bind(int port) { + if (init_socket(SOCK_DGRAM) < 0) + return -1; + + struct sockaddr_in localHost; + std::memset(&localHost, 0, sizeof(localHost)); + + localHost.sin_family = AF_INET; + localHost.sin_port = htons(port); + localHost.sin_addr.s_addr = INADDR_ANY; + + if (lwip_bind(_sock_fd, (const struct sockaddr *) &localHost, sizeof(localHost)) < 0) { + close(); + return -1; + } + + return 0; +} + +int UDPSocket::join_multicast_group(const char* address) { + struct ip_mreq mreq; + + // Set up group address + mreq.imr_multiaddr.s_addr = inet_addr(address); + mreq.imr_interface.s_addr = htonl(INADDR_ANY); + + return set_option(IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)); +} + +int UDPSocket::set_broadcasting(bool broadcast) { + int option = (broadcast) ? (1) : (0); + return set_option(SOL_SOCKET, SO_BROADCAST, &option, sizeof(option)); +} + +// -1 if unsuccessful, else number of bytes written +int UDPSocket::sendTo(Endpoint &remote, char *packet, int length) { + if (_sock_fd < 0) + return -1; + + if (!_blocking) { + TimeInterval timeout(_timeout); + if (wait_writable(timeout) != 0) + return 0; + } + + return lwip_sendto(_sock_fd, packet, length, 0, (const struct sockaddr *) &remote._remoteHost, sizeof(remote._remoteHost)); +} + +// -1 if unsuccessful, else number of bytes received +int UDPSocket::receiveFrom(Endpoint &remote, char *buffer, int length) { + if (_sock_fd < 0) + return -1; + + if (!_blocking) { + TimeInterval timeout(_timeout); + if (wait_readable(timeout) != 0) + return 0; + } + remote.reset_address(); + socklen_t remoteHostLen = sizeof(remote._remoteHost); + return lwip_recvfrom(_sock_fd, buffer, length, 0, (struct sockaddr*) &remote._remoteHost, &remoteHostLen); +}