root/webserver/example/freeRTOSexample/EnergyMeters/Common/ethernet/FreeRTOS-uIP/psock.c

/*
 * Copyright (c) 2004, Swedish Institute of Computer Science.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 * This file is part of the uIP TCP/IP stack
 *
 * Author: Adam Dunkels <adam@sics.se>
 *
 * $Id: psock.c,v 1.1 2007/01/04 11:06:40 adamdunkels Exp $
 */
#include <stdio.h>
#include <string.h>

#include "uipopt.h"
#include "psock.h"
#include "uip.h"

#define STATE_NONE                              0
#define STATE_ACKED                             1
#define STATE_READ                              2
#define STATE_BLOCKED_NEWDATA   3
#define STATE_BLOCKED_CLOSE             4
#define STATE_BLOCKED_SEND              5
#define STATE_DATA_SENT                 6

/*
 * Return value of the buffering functions that indicates that a
 * buffer was not filled by incoming data.
 *
 */
#define BUF_NOT_FULL    0
#define BUF_NOT_FOUND   0

/*
 * Return value of the buffering functions that indicates that a
 * buffer was completely filled by incoming data.
 *
 */
#define BUF_FULL        1

/*
 * Return value of the buffering functions that indicates that an
 * end-marker byte was found.
 *
 */
#define BUF_FOUND       2

/*---------------------------------------------------------------------------*/
static void buf_setup( struct psock_buf *buf, u8_t *bufptr, u16_t bufsize )
{
        buf->ptr = bufptr;
        buf->left = bufsize;
}

/*---------------------------------------------------------------------------*/
static u8_t buf_bufdata( struct psock_buf *buf, u16_t len, u8_t **dataptr, u16_t *datalen )
{
        ( void ) len;

        if( *datalen < buf->left )
        {
                memcpy( buf->ptr, *dataptr, *datalen );
                buf->ptr += *datalen;
                buf->left -= *datalen;
                *dataptr += *datalen;
                *datalen = 0;
                return BUF_NOT_FULL;
        }
        else if( *datalen == buf->left )
        {
                memcpy( buf->ptr, *dataptr, *datalen );
                buf->ptr += *datalen;
                buf->left = 0;
                *dataptr += *datalen;
                *datalen = 0;
                return BUF_FULL;
        }
        else
        {
                memcpy( buf->ptr, *dataptr, buf->left );
                buf->ptr += buf->left;
                *datalen -= buf->left;
                *dataptr += buf->left;
                buf->left = 0;
                return BUF_FULL;
        }
}

/*---------------------------------------------------------------------------*/
static u8_t buf_bufto( register struct psock_buf *buf, u8_t endmarker, register u8_t **dataptr, register u16_t *datalen )
{
        u8_t    c;
        while( buf->left > 0 && *datalen > 0 )
        {
                c = *buf->ptr = **dataptr;
                ++ *dataptr;
                ++buf->ptr;
                -- *datalen;
                --buf->left;

                if( c == endmarker )
                {
                        return BUF_FOUND;
                }
        }

        if( *datalen == 0 )
        {
                return BUF_NOT_FOUND;
        }

        while( *datalen > 0 )
        {
                c = **dataptr;
                -- *datalen;
                ++ *dataptr;

                if( c == endmarker )
                {
                        return BUF_FOUND | BUF_FULL;
                }
        }

        return BUF_FULL;
}

/*---------------------------------------------------------------------------*/
static char send_data( register struct psock *s )
{
        if( s->state != STATE_DATA_SENT || uip_rexmit() )
        {
                if( s->sendlen > uip_mss() )
                {
                        uip_send( s->sendptr, uip_mss() );
                }
                else
                {
                        uip_send( s->sendptr, s->sendlen );
                }

                s->state = STATE_DATA_SENT;
                return 1;
        }

        return 0;
}

/*---------------------------------------------------------------------------*/
static char data_acked( register struct psock *s )
{
        if( s->state == STATE_DATA_SENT && uip_acked() )
        {
                if( s->sendlen > uip_mss() )
                {
                        s->sendlen -= uip_mss();
                        s->sendptr += uip_mss();
                }
                else
                {
                        s->sendptr += s->sendlen;
                        s->sendlen = 0;
                }

                s->state = STATE_ACKED;
                return 1;
        }

        return 0;
}

/*---------------------------------------------------------------------------*/
PT_THREAD( psock_send ( register struct psock *s, const char *buf, unsigned int len ) )
{
        PT_BEGIN( &s->psockpt );

        /* If there is no data to send, we exit immediately. */
        if( len == 0 )
        {
                PT_EXIT( &s->psockpt );
        }

        /* Save the length of and a pointer to the data that is to be
     sent. */
        s->sendptr = ( u8_t * ) buf;
        s->sendlen = len;

        s->state = STATE_NONE;

        /* We loop here until all data is sent. The s->sendlen variable is
     updated by the data_sent() function. */
        while( s->sendlen > 0 )
        {
                /*
     * The condition for this PT_WAIT_UNTIL is a little tricky: the
     * protothread will wait here until all data has been acknowledged
     * (data_acked() returns true) and until all data has been sent
     * (send_data() returns true). The two functions data_acked() and
     * send_data() must be called in succession to ensure that all
     * data is sent. Therefore the & operator is used instead of the
     * && operator, which would cause only the data_acked() function
     * to be called when it returns false.
     */
                PT_WAIT_UNTIL( &s->psockpt, data_acked(s) & send_data(s) );
        }

        s->state = STATE_NONE;

        PT_END( &s->psockpt );
}

/*---------------------------------------------------------------------------*/
PT_THREAD( psock_generator_send ( register struct psock *s, unsigned short ( *generate ) ( void * ), void *arg ) )
{
        PT_BEGIN( &s->psockpt );

        /* Ensure that there is a generator function to call. */
        if( generate == NULL )
        {
                PT_EXIT( &s->psockpt );
        }

        /* Call the generator function to generate the data in the
     uip_appdata buffer. */
        s->sendlen = generate( arg );
        s->sendptr = uip_appdata;

        s->state = STATE_NONE;
        do
        {
                /* Call the generator function again if we are called to perform a
       retransmission. */
                if( uip_rexmit() )
                {
                        generate( arg );
                }

                /* Wait until all data is sent and acknowledged. */
                PT_WAIT_UNTIL( &s->psockpt, data_acked(s) & send_data(s) );
        } while( s->sendlen > 0 );

        s->state = STATE_NONE;

        PT_END( &s->psockpt );
}

/*---------------------------------------------------------------------------*/
u16_t psock_datalen( struct psock *psock )
{
        return psock->bufsize - psock->buf.left;
}

/*---------------------------------------------------------------------------*/
char psock_newdata( struct psock *s )
{
        if( s->readlen > 0 )
        {
                /* There is data in the uip_appdata buffer that has not yet been
       read with the PSOCK_READ functions. */
                return 1;
        }
        else if( s->state == STATE_READ )
        {
                /* All data in uip_appdata buffer already consumed. */
                s->state = STATE_BLOCKED_NEWDATA;
                return 0;
        }
        else if( uip_newdata() )
        {
                /* There is new data that has not been consumed. */
                return 1;
        }
        else
        {
                /* There is no new data. */
                return 0;
        }
}

/*---------------------------------------------------------------------------*/
PT_THREAD( psock_readto ( register struct psock *psock, unsigned char c ) )
{
        PT_BEGIN( &psock->psockpt );

        buf_setup( &psock->buf, ( u8_t * ) psock->bufptr, psock->bufsize );

        /* XXX: Should add buf_checkmarker() before do{} loop, if
     incoming data has been handled while waiting for a write. */
        do
        {
                if( psock->readlen == 0 )
                {
                        PT_WAIT_UNTIL( &psock->psockpt, psock_newdata(psock) );
                        psock->state = STATE_READ;
                        psock->readptr = ( u8_t * ) uip_appdata;
                        psock->readlen = uip_datalen();
                }
        } while( (buf_bufto(&psock->buf, c, &psock->readptr, &psock->readlen) & BUF_FOUND) == 0 );

        if( psock_datalen(psock) == 0 )
        {
                psock->state = STATE_NONE;
                PT_RESTART( &psock->psockpt );
        }

        PT_END( &psock->psockpt );
}

/*---------------------------------------------------------------------------*/
PT_THREAD( psock_readbuf ( register struct psock *psock ) )
{
        PT_BEGIN( &psock->psockpt );

        buf_setup( &psock->buf, ( u8_t * ) psock->bufptr, psock->bufsize );

        /* XXX: Should add buf_checkmarker() before do{} loop, if
     incoming data has been handled while waiting for a write. */
        do
        {
                if( psock->readlen == 0 )
                {
                        PT_WAIT_UNTIL( &psock->psockpt, psock_newdata(psock) );
                        printf( "Waited for newdata\n" );
                        psock->state = STATE_READ;
                        psock->readptr = ( u8_t * ) uip_appdata;
                        psock->readlen = uip_datalen();
                }
        } while( buf_bufdata(&psock->buf, psock->bufsize, &psock->readptr, &psock->readlen) != BUF_FULL );

        if( psock_datalen(psock) == 0 )
        {
                psock->state = STATE_NONE;
                PT_RESTART( &psock->psockpt );
        }

        PT_END( &psock->psockpt );
}

/*---------------------------------------------------------------------------*/
void psock_init( register struct psock *psock, char *buffer, unsigned int buffersize )
{
        psock->state = STATE_NONE;
        psock->readlen = 0;
        psock->bufptr = buffer;
        psock->bufsize = buffersize;
        buf_setup( &psock->buf, ( u8_t * ) buffer, buffersize );
        PT_INIT( &psock->pt );
        PT_INIT( &psock->psockpt );
}

/*---------------------------------------------------------------------------*/