UDPSocket.cpp

00001 /* Copyright (C) 2012 mbed.org, MIT License
00002  *
00003  * Permission is hereby granted, free of charge, to any person obtaining a copy of this software
00004  * and associated documentation files (the "Software"), to deal in the Software without restriction,
00005  * including without limitation the rights to use, copy, modify, merge, publish, distribute,
00006  * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
00007  * furnished to do so, subject to the following conditions:
00008  *
00009  * The above copyright notice and this permission notice shall be included in all copies or
00010  * substantial portions of the Software.
00011  *
00012  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING
00013  * BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
00014  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
00015  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00016  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
00017  */
00018 
00019 #include "UDPSocket.h"
00020 
00021 static int udp_local_port;
00022 
00023 UDPSocket::UDPSocket()
00024 {
00025 }
00026 // After init function, bind() should be called.
00027 int UDPSocket::init(void)
00028 {
00029     if (_sock_fd < 0) {
00030         _sock_fd = eth->new_socket();
00031     }
00032     if (eth->setProtocol(_sock_fd, WIZnet_Chip::UDP) == false) return -1;
00033     return 0;
00034 }
00035 
00036 // Server initialization
00037 int UDPSocket::bind(int port)
00038 {
00039     if (_sock_fd < 0) {
00040         _sock_fd = eth->new_socket();
00041         if (_sock_fd < 0) {
00042             return -1;
00043         }
00044     }
00045     // set local port
00046     if (port != 0) {
00047         eth->sreg<uint16_t>(_sock_fd, Sn_PORT, port);
00048     } else {
00049         udp_local_port++;
00050         eth->sreg<uint16_t>(_sock_fd, Sn_PORT, udp_local_port);
00051     }
00052     // set udp protocol
00053     eth->setProtocol(_sock_fd, WIZnet_Chip::UDP);
00054     eth->scmd(_sock_fd, WIZnet_Chip::OPEN);
00055     return 0;
00056 }
00057 
00058 // -1 if unsuccessful, else number of bytes written
00059 int UDPSocket::sendTo(Endpoint &remote, char *packet, int length)
00060 {
00061     int size = eth->wait_writeable(_sock_fd, _blocking ? -1 : _timeout, length-1);
00062     if (size < 0) {
00063         return -1;
00064     }
00065     confEndpoint(remote);
00066     int ret = eth->send(_sock_fd, packet, length);
00067     return ret;
00068 }
00069 
00070 // -1 if unsuccessful, else number of bytes received
00071 int UDPSocket::receiveFrom(Endpoint &remote, char *buffer, int length)
00072 {
00073     uint8_t info[8];
00074     int size = eth->wait_readable(_sock_fd, _blocking ? -1 : _timeout, sizeof(info));
00075     if (size < 0) {
00076         return -1;
00077     }
00078     eth->recv(_sock_fd, (char*)info, sizeof(info));
00079     readEndpoint(remote, info);
00080     int udp_size = info[6]<<8|info[7];
00081     //TEST_ASSERT(udp_size <= (size-sizeof(info)));
00082     if (udp_size > (size-sizeof(info))) {
00083         return -1;
00084     }
00085 
00086     /* Perform Length check here to prevent buffer overrun */
00087     /* fixed by Sean Newton (https://developer.mbed.org/users/SeanNewton/) */
00088     if (udp_size > length) {
00089         //printf("udp_size: %d\n",udp_size);
00090         return -1;
00091     }
00092     return eth->recv(_sock_fd, buffer, udp_size);
00093 }
00094 
00095 void UDPSocket::confEndpoint(Endpoint & ep)
00096 {
00097     char * host = ep.get_address();
00098     // set remote host
00099     eth->sreg_ip(_sock_fd, Sn_DIPR, host);
00100     // set remote port
00101     eth->sreg<uint16_t>(_sock_fd, Sn_DPORT, ep.get_port());
00102 }
00103 
00104 void UDPSocket::readEndpoint(Endpoint & ep, uint8_t info[])
00105 {
00106     char addr[17];
00107     snprintf(addr, sizeof(addr), "%d.%d.%d.%d", info[0], info[1], info[2], info[3]);
00108     uint16_t port = info[4]<<8|info[5];
00109     ep.set_address(addr, port);
00110 }
00111