| /* |
| * 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/def.h" |
| #include "netif/sioslipif.h" |
| #include "lwip/pbuf.h" |
| #include "lwip/sys.h" |
| #include "lwip/stats.h" |
| |
| /* The maximum size that an incoming packet can have. */ |
| #define MAX_SIZE 1500 |
| |
| #define SLIP_END 0300 |
| #define SLIP_ESC 0333 |
| #define SLIP_ESC_END 0334 |
| #define SLIP_ESC_ESC 0335 |
| |
| /* Define those to whatever is needed to send and receive one byte of |
| data. */ |
| #define SIO_SEND(c) |
| #define SIO_RECV(c) |
| |
| static const unsigned char slip_end = SLIP_END, |
| slip_esc = SLIP_ESC, |
| slip_esc_end = SLIP_ESC_END, |
| slip_esc_esc = SLIP_ESC_ESC; |
| |
| /*-----------------------------------------------------------------------------------*/ |
| static err_t |
| sioslipif_output(struct netif *netif, struct pbuf *p, struct ip_addr *ipaddr) |
| { |
| struct pbuf *q; |
| int i; |
| unsigned char *ptr; |
| u8_t c; |
| /* Send pbuf out on the serial I/O device. */ |
| SIO_SEND(slip_end); |
| |
| for(q = p; q != NULL; q = q->next) { |
| ptr = q->payload; |
| for(i = 0; i < q->len; i++) { |
| c = *ptr++; |
| switch(c) { |
| case SLIP_END: |
| SIO_SEND(slip_esc); |
| SIO_SEND(slip_esc_end); |
| break; |
| case SLIP_ESC: |
| SIO_SEND(slip_esc); |
| SIO_SEND(slip_esc_esc); |
| break; |
| default: |
| SIO_SEND(c); |
| break; |
| } |
| } |
| } |
| #ifdef LINK_STATS |
| stats.link.xmit++; |
| #endif /* LINK_STATS */ |
| SIO_SEND(slip_end); |
| |
| return ERR_OK; |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| static struct pbuf * |
| sioslipif_input(void) |
| { |
| u8_t c; |
| struct pbuf *p, *q; |
| int recved; |
| int i; |
| |
| q = p = NULL; |
| recved = i = 0; |
| c = 0; |
| |
| while(1) { |
| SIO_RECV(c); |
| switch(c) { |
| case SLIP_END: |
| if(p == NULL) { |
| return sioslipif_input(); |
| } |
| if(recved > 0) { |
| /* Received whole packet. */ |
| pbuf_realloc(q, recved); |
| #ifdef LINK_STATS |
| stats.link.recv++; |
| #endif /* LINK_STATS */ |
| return q; |
| } |
| break; |
| case SLIP_ESC: |
| SIO_RECV(c); |
| switch(c) { |
| case SLIP_ESC_END: |
| c = SLIP_END; |
| break; |
| case SLIP_ESC_ESC: |
| c = SLIP_ESC; |
| break; |
| } |
| /* FALLTHROUGH */ |
| default: |
| if(p == NULL) { |
| p = pbuf_alloc(PBUF_LINK, 128, PBUF_POOL); |
| #ifdef LINK_STATS |
| if(p == NULL) { |
| stats.link.drop++; |
| } |
| #endif /* LINK_STATS */ |
| if(q != NULL) { |
| pbuf_chain(q, p); |
| } else { |
| q = p; |
| } |
| } |
| if(p != NULL && recved < MAX_SIZE) { |
| ((u8_t *)p->payload)[i] = c; |
| recved++; |
| i++; |
| if(i >= p->len) { |
| i = 0; |
| p = NULL; |
| } |
| } |
| break; |
| } |
| |
| } |
| return NULL; |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| static void |
| sioslipif_loop(void *arg) |
| { |
| struct pbuf *p; |
| struct netif *netif; |
| |
| netif = arg; |
| while(1) { |
| p = sioslipif_input(); |
| netif->input(p, netif); |
| } |
| } |
| /*-----------------------------------------------------------------------------------*/ |
| void |
| sioslipif_init(struct netif *netif) |
| { |
| netif->state = NULL; |
| netif->name[0] = 's'; |
| netif->name[1] = 'l'; |
| netif->output = sioslipif_output; |
| |
| sys_thread_new((void *)sioslipif_loop, netif); |
| /* Do some magic to make it possible to receive data from the serial I/O device. */ |
| } |
| /*-----------------------------------------------------------------------------------*/ |