see http://mbed.org/users/okini3939/notebook/wattmeter-shield-on-mbed/

Dependencies:   mbed

Fork of GSwifi_xively by gs fan

GSwifiInterface/Socket/UDPSocket.cpp

Committer:
okini3939
Date:
2013-11-27
Revision:
4:9a2415f2ab07

File content as of revision 4:9a2415f2ab07:

/* 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.
 */
/* Copyright (C) 2013 gsfan, MIT License
 *  port to the GainSpan Wi-FI module GS1011
 */

#include "UDPSocket.h"

#include <string>
#include <algorithm>

UDPSocket::UDPSocket()
{
    endpoint_connected = false;
}

int UDPSocket::init(void)
{
    _server = false;
    return 0;
}

// Server initialization
int UDPSocket::bind(int port)
{
    _port = port;
    _server = true;
    return 0;
}

// -1 if unsuccessful, else number of bytes written
int UDPSocket::sendTo(Endpoint &remote, char *packet, int length)
{
    Timer tmr;
    int idx = 0;

    if (_cid < 0 && _wifi->isAssociated()) {
        // Socket open
        if (_server) {
            _cid = _wifi->listen(GSwifi::PROTO_UDP, _port);
        } else {
            _cid = _wifi->open(GSwifi::PROTO_UDP, remote.get_address(), remote.get_port(), _port);
        }
        if (_cid < 0) return -1;
    }

    tmr.start();

    while ((tmr.read_ms() < _timeout) || _blocking) {

        if (_server) {
            idx += _wifi->sendto(_cid, packet, length, remote.get_address(), remote.get_port());
        } else {
            idx += _wifi->send(_cid, packet, length);
        }
        if (idx < 0) {
            if (!_wifi->isConnected(_cid)) _cid = -1;
        }

        if (idx == length)
            return idx;
    }
    return (idx == 0) ? -1 : idx;
}

// -1 if unsuccessful, else number of bytes received
int UDPSocket::receiveFrom(Endpoint &remote, char *buffer, int length)
{
    Timer tmr;
    int idx = 0;
    int time = -1;
    char ip[16];
    int port;

    if (_cid < 0 && _wifi->isAssociated()) {
        // Socket open
        if (_server) {
            _cid = _wifi->listen(GSwifi::PROTO_UDP, _port);
        } else {
            _cid = _wifi->open(GSwifi::PROTO_UDP, remote.get_address(), remote.get_port(), _port);
        }
        if (_cid < 0) return -1;
    }

    if (_blocking) {
        tmr.start();
        while (time < _timeout + 20) {
            if (_wifi->readable(_cid)) {
                break;
            }
            time = tmr.read_ms();
        }
        if (time >= _timeout + 20) {
            return -1;
        }
    }

    tmr.reset();
    time = -1;
    tmr.start();

    while (time < _timeout) {

        if (_server) {
            idx += _wifi->recvfrom(_cid, &buffer[idx], length - idx, ip, &port);
        } else {
            idx += _wifi->recv(_cid, &buffer[idx], length - idx);
        }
        if (idx < 0) {
            if (!_wifi->isConnected(_cid)) _cid = -1;
            return -1;
        }

        if (idx == length) {
            break;
        }
        
        time = tmr.read_ms();
    }

    if (_server) {
        remote.set_address(ip, port);
    }
    return (idx == 0) ? -1 : idx;
}