#pragma GCC diagnostic ignored "-Wpointer-sign"
#pragma GCC diagnostic ignored "-Wstrict-aliasing"
#pragma GCC diagnostic ignored "-Wcast-align"
#pragma GCC diagnostic ignored "-Wcast-qual"
#pragma GCC diagnostic ignored "-Wunused-but-set-variable"

/*
 * 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 1.2 2006/06/12 08:00:30 adam 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)
{
    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 = 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, 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, 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);
}
/*---------------------------------------------------------------------------*/
PT_THREAD(psock_readbuf_len(register struct psock *psock, uint16_t len))
{
    PT_BEGIN(&psock->psockpt);

    // setup to read the smaller of buffer size or len
    if(len > psock->bufsize) len= psock->bufsize;
    buf_setup(&psock->buf, psock->bufptr, len);

    /* XXX: Should add buf_checkmarker() before do{} loop, if
    incoming data has been handled while waiting for a write. */

    /* read len bytes or to end of data */
    do {
        if (psock->readlen == 0) {
            PT_WAIT_UNTIL(&psock->psockpt, psock_newdata(psock));
            psock->state = STATE_READ;
            psock->readptr = (uint8_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, buffer, buffersize);
    PT_INIT(&psock->pt);
    PT_INIT(&psock->psockpt);
}
/*---------------------------------------------------------------------------*/
