lwip/proj/minimal/echo.c
2002-10-19 12:59:30 +00:00

221 lines
5.5 KiB
C

/*
* Copyright (c) 2001, 2002 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. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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 lwIP TCP/IP stack.
*
* Author: Adam Dunkels <adam@sics.se>
*
*/
#include "lwip/debug.h"
#include "lwip/stats.h"
#include "lwip/tcp.h"
struct echo_state {
struct pbuf *p;
u8_t failed;
#define FAILED_MAX 8
};
/*-----------------------------------------------------------------------------------*/
static void
echo_err(void *arg, err_t err)
{
struct echo_state *es = arg;
if(arg != NULL) {
pbuf_free(es->p);
mem_free(arg);
}
}
/*-----------------------------------------------------------------------------------*/
static void
close_conn(struct tcp_pcb *pcb, struct echo_state *es)
{
tcp_arg(pcb, NULL);
#if 0
tcp_sent(pcb, NULL);
tcp_recv(pcb, NULL);
#endif /* 0 */
if(es != NULL) {
pbuf_free(es->p);
mem_free(es);
}
tcp_close(pcb);
}
/*-----------------------------------------------------------------------------------*/
static void
send_buf(struct tcp_pcb *pcb, struct echo_state *es)
{
struct pbuf *q;
do {
q = es->p;
es->p = pbuf_dechain(q);
if(tcp_write(pcb, q->payload, q->len, 1) == ERR_MEM) {
pbuf_chain(q, es->p);
es->p = q;
return;
}
tcp_recved(pcb, q->len);
pbuf_free(q);
} while(es->p != NULL);
}
/*-----------------------------------------------------------------------------------*/
static err_t
echo_poll(void *arg, struct tcp_pcb *pcb)
{
struct echo_state *es;
if(arg == NULL) {
return tcp_close(pcb);
}
es = arg;
if(es->failed >= FAILED_MAX) {
close_conn(pcb, es);
tcp_abort(pcb);
return ERR_ABRT;
}
if(es->p != NULL) {
++es->failed;
send_buf(pcb, es);
}
return ERR_OK;
}
/*-----------------------------------------------------------------------------------*/
static err_t
echo_sent(void *arg, struct tcp_pcb *pcb, u16_t len)
{
struct echo_state *es;
es = arg;
if(es != NULL && es->p != NULL) {
send_buf(pcb, es);
}
return ERR_OK;
}
/*-----------------------------------------------------------------------------------*/
static err_t
echo_recv(void *arg, struct tcp_pcb *pcb, struct pbuf *p, err_t err)
{
struct echo_state *es;
es = arg;
if(p == NULL) {
close_conn(pcb, es);
return ERR_OK;
}
if(es->p != NULL) {
pbuf_chain(es->p, p);
} else {
es->p = p;
}
send_buf(pcb, es);
return ERR_OK;
}
/*-----------------------------------------------------------------------------------*/
static err_t
echo_accept(void *arg, struct tcp_pcb *pcb, err_t err)
{
struct echo_state *es;
tcp_setprio(pcb, TCP_PRIO_MIN);
/* Allocate memory for the structure that holds the state of the
connection. */
es = mem_malloc(sizeof(struct echo_state));
if(es == NULL) {
return ERR_MEM;
}
/* Initialize the structure. */
es->p = NULL;
es->failed = 0;
/* Tell TCP that this is the structure we wish to be passed for our
callbacks. */
tcp_arg(pcb, es);
/* Tell TCP that we wish to be informed of incoming data by a call
to the http_recv() function. */
#if 0
tcp_recv(pcb, echo_recv);
tcp_err(pcb, echo_err);
#endif /* 0 */
tcp_poll(pcb, echo_poll, 2);
return ERR_OK;
}
/*-----------------------------------------------------------------------------------*/
void
echo_init(void)
{
struct tcp_pcb *pcb;
pcb = tcp_new();
tcp_bind(pcb, IP_ADDR_ANY, 7);
pcb = tcp_listen(pcb);
#if 0
tcp_accept(pcb, echo_accept);
#endif /* 0 */
}
/*-----------------------------------------------------------------------------------*/
err_t
lwip_tcp_event(void *arg, struct tcp_pcb *pcb,
enum lwip_event ev, struct pbuf *p,
u16_t size, err_t err)
{
switch(ev) {
case LWIP_EVENT_ACCEPT:
return echo_accept(arg, pcb, err);
case LWIP_EVENT_SENT:
return echo_sent(arg, pcb, size);
case LWIP_EVENT_RECV:
return echo_recv(arg, pcb, p, err);
case LWIP_EVENT_ERR:
echo_err(arg, err);
break;
case LWIP_EVENT_POLL:
return echo_poll(arg, pcb);
default:
break;
}
return ERR_OK;
}
/*-----------------------------------------------------------------------------------*/