contiki/core/net/psock.c

331 lines
9.4 KiB
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 Contiki operating system.
*
* Author: Adam Dunkels <adam@sics.se>
*
* $Id: psock.c,v 1.12 2010/06/15 14:19:22 nifi Exp $
*/
#include <string.h>
#include "net/psock.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,
uint8_t *bufptr, uint16_t bufsize)
{
buf->ptr = bufptr;
buf->left = bufsize;
}
/*---------------------------------------------------------------------------*/
static uint8_t
buf_bufdata(struct psock_buf *buf, uint16_t len,
uint8_t **dataptr, uint16_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 uint8_t
buf_bufto(CC_REGISTER_ARG struct psock_buf *buf, uint8_t endmarker,
CC_REGISTER_ARG uint8_t **dataptr, CC_REGISTER_ARG uint16_t *datalen)
{
uint8_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
data_is_sent_and_acked(CC_REGISTER_ARG struct psock *s)
{
/* If data has previously been sent, and the data has been acked, we
increase the send pointer and call send_data() to send more
data. */
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 0;
} else 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(CC_REGISTER_ARG struct psock *s, const uint8_t *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 protothread will wait here until all data has been
* acknowledged and sent (data_is_acked_and_send() returns 1).
*/
PT_WAIT_UNTIL(&s->psockpt, data_is_sent_and_acked(s));
}
s->state = STATE_NONE;
PT_END(&s->psockpt);
}
/*---------------------------------------------------------------------------*/
PT_THREAD(psock_generator_send(CC_REGISTER_ARG 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);
}
s->state = STATE_NONE;
do {
/* Call the generator function to generate the data in the
uip_appdata buffer. */
s->sendlen = generate(arg);
s->sendptr = uip_appdata;
if(s->sendlen > uip_mss()) {
uip_send(s->sendptr, uip_mss());
} else {
uip_send(s->sendptr, s->sendlen);
}
s->state = STATE_DATA_SENT;
/* Wait until all data is sent and acknowledged. */
// if (!s->sendlen) break; //useful debugging aid
PT_YIELD_UNTIL(&s->psockpt, uip_acked() || uip_rexmit());
} while(!uip_acked());
s->state = STATE_NONE;
PT_END(&s->psockpt);
}
/*---------------------------------------------------------------------------*/
uint16_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(CC_REGISTER_ARG 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 = (uint8_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_len(CC_REGISTER_ARG struct psock *psock, uint16_t len))
{
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. */
/* 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_NOT_FULL &&
psock_datalen(psock) < len);
if(psock_datalen(psock) == 0) {
psock->state = STATE_NONE;
PT_RESTART(&psock->psockpt);
}
PT_END(&psock->psockpt);
}
/*---------------------------------------------------------------------------*/
void
psock_init(CC_REGISTER_ARG struct psock *psock,
uint8_t *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);
}
/*---------------------------------------------------------------------------*/