445 lines
11 KiB
C
445 lines
11 KiB
C
/*
|
|
* Copyright (c) 2014, SICS Swedish ICT.
|
|
* 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.
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* \file
|
|
* Alternative implementation for SLIP:
|
|
* 1. Accepts more than two packet
|
|
* 2. Disables UART rx interrupt when buffer is full
|
|
* (thus invoking flow control if configured)
|
|
* \author
|
|
* Niklas Finne <nfi@sics.se>
|
|
* Beshr Al Nahas <beshr@sics.se>
|
|
*
|
|
*/
|
|
|
|
#include "contiki.h"
|
|
|
|
#include <MicroInt.h>
|
|
#include "net/ip/uip.h"
|
|
#include "net/ipv4/uip-fw.h"
|
|
#define BUF ((struct uip_tcpip_hdr *)&uip_buf[UIP_LLH_LEN])
|
|
|
|
#include "dev/slip.h"
|
|
|
|
#define DEBUG 0
|
|
#if DEBUG
|
|
#include <stdio.h>
|
|
#define PRINTF(...) printf(__VA_ARGS__)
|
|
#define PUTCHAR(X) do { putchar(X); putchar('\n'); } while(0)
|
|
#else
|
|
#define PRINTF(...) do {} while(0)
|
|
#define PUTCHAR(X) do {} while(0)
|
|
#endif
|
|
|
|
#define SLIP_END 0300
|
|
#define SLIP_ESC 0333
|
|
#define SLIP_ESC_END 0334
|
|
#define SLIP_ESC_ESC 0335
|
|
#define SLIP_NEUTRAL 0 /* means: none of the above */
|
|
#define SLIP_ESC_XON 0336
|
|
#define SLIP_ESC_XOFF 0337
|
|
#define XON ((unsigned char)17)
|
|
#define XOFF ((unsigned char)19)
|
|
#if UART_XONXOFF_FLOW_CTRL
|
|
volatile unsigned char xonxoff_state = XON;
|
|
#endif /* UART_XONXOFF_FLOW_CTRL */
|
|
|
|
PROCESS(slip_process, "SLIP driver");
|
|
|
|
#include "dev/uart0.h"
|
|
#define STORE_UART_INTERRUPTS uart0_store_interrupts
|
|
#define RESTORE_UART_INTERRUPTS uart0_restore_interrupts
|
|
#define DISABLE_UART_INTERRUPTS uart0_disable_interrupts
|
|
#define ENABLE_UART_INTERRUPTS uart0_enable_interrupts
|
|
|
|
/**
|
|
* @brief A block of code may be made atomic by wrapping it with this
|
|
* macro. Something which is atomic cannot be interrupted by interrupts.
|
|
*/
|
|
/* A specific ATMOIC that disables UART interrupts only */
|
|
#define ATOMIC(blah) \
|
|
{ \
|
|
/* STORE_UART_INTERRUPTS(); */ \
|
|
DISABLE_UART_INTERRUPTS(); \
|
|
{ blah } \
|
|
/* RESTORE_UART_INTERRUPTS(); */ \
|
|
ENABLE_UART_INTERRUPTS(); \
|
|
}
|
|
|
|
/* A generic ATMOIC that disables all interrupts */
|
|
#define GLOBAL_ATOMIC(blah) \
|
|
{ \
|
|
MICRO_DISABLE_INTERRUPTS(); \
|
|
{ blah } \
|
|
MICRO_ENABLE_INTERRUPTS(); \
|
|
}
|
|
|
|
#if 1
|
|
#define SLIP_STATISTICS(statement)
|
|
#else
|
|
uint16_t slip_drop_bytes, slip_overflow, slip_error_drop;
|
|
/* No used in this file */
|
|
uint16_t slip_rubbish, slip_twopackets, slip_ip_drop;
|
|
unsigned long slip_received, slip_frames;
|
|
#define SLIP_STATISTICS(statement) statement
|
|
#endif
|
|
|
|
/* Must be at least one byte larger than UIP_BUFSIZE (for SLIP_END)! */
|
|
#ifdef SLIP_CONF_RX_BUFSIZE
|
|
#define RX_BUFSIZE SLIP_CONF_RX_BUFSIZE
|
|
|
|
#if RX_BUFSIZE < (UIP_BUFSIZE - UIP_LLH_LEN + 16)
|
|
#error "SLIP_CONF_RX_BUFSIZE too small for UIP_BUFSIZE"
|
|
#endif
|
|
|
|
#else
|
|
#define RX_BUFSIZE (UIP_CONF_BUFFER_SIZE * 2)
|
|
#endif
|
|
|
|
/*
|
|
* Variables begin and end manage the buffer space in a cyclic
|
|
* fashion. The first used byte is at begin and end is one byte past
|
|
* the last. I.e. [begin, end) is the actively used space.
|
|
*/
|
|
|
|
static volatile uint16_t begin, end, end_counter;
|
|
static uint8_t rxbuf[RX_BUFSIZE];
|
|
static volatile uint8_t is_dropping = 0;
|
|
static volatile uint8_t is_full = 0;
|
|
|
|
static void (*input_callback)(void) = NULL;
|
|
/*---------------------------------------------------------------------------*/
|
|
void
|
|
slip_set_input_callback(void (*c)(void))
|
|
{
|
|
input_callback = c;
|
|
}
|
|
static void
|
|
slip_write_char(uint8_t c)
|
|
{
|
|
/* Escape SLIP control characters */
|
|
if(c == SLIP_END) {
|
|
slip_arch_writeb(SLIP_ESC);
|
|
c = SLIP_ESC_END;
|
|
} else if(c == SLIP_ESC) {
|
|
slip_arch_writeb(SLIP_ESC);
|
|
c = SLIP_ESC_ESC;
|
|
}
|
|
#if UART_XONXOFF_FLOW_CTRL
|
|
/* Escape XON/XOFF characters */
|
|
else if(c == XON) {
|
|
slip_arch_writeb(SLIP_ESC);
|
|
c = SLIP_ESC_XON;
|
|
} else if(c == XOFF) {
|
|
slip_arch_writeb(SLIP_ESC);
|
|
c = SLIP_ESC_XOFF;
|
|
}
|
|
#endif /* UART_XONXOFF_FLOW_CTRL */
|
|
slip_arch_writeb(c);
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
uint8_t
|
|
slip_write(const void *_ptr, int len)
|
|
{
|
|
const uint8_t *ptr = _ptr;
|
|
uint16_t i;
|
|
uint8_t c;
|
|
|
|
slip_arch_writeb(SLIP_END);
|
|
|
|
for(i = 0; i < len; ++i) {
|
|
c = *ptr++;
|
|
slip_write_char(c);
|
|
}
|
|
slip_arch_writeb(SLIP_END);
|
|
|
|
return len;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
/* slip_send: forward (IPv4) packets with {UIP_FW_NETIF(..., slip_send)}
|
|
* was used in slip-bridge.c
|
|
*/
|
|
uint8_t
|
|
slip_send(void)
|
|
{
|
|
uint16_t i;
|
|
uint8_t *ptr;
|
|
uint8_t c;
|
|
|
|
slip_arch_writeb(SLIP_END);
|
|
|
|
ptr = &uip_buf[UIP_LLH_LEN];
|
|
for(i = 0; i < uip_len; ++i) {
|
|
c = *ptr++;
|
|
slip_write_char(c);
|
|
}
|
|
slip_arch_writeb(SLIP_END);
|
|
|
|
return UIP_FW_OK;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
static void
|
|
rxbuf_init(void)
|
|
{
|
|
begin = end = end_counter = 0;
|
|
is_dropping = 0;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Upper half does the polling. */
|
|
static uint16_t
|
|
slip_poll_handler(uint8_t *outbuf, uint16_t blen)
|
|
{
|
|
uint16_t len;
|
|
uint16_t pos;
|
|
uint8_t c;
|
|
uint8_t state;
|
|
|
|
if(end_counter == 0 && is_full == 0) {
|
|
return 0;
|
|
}
|
|
for(len = 0, pos = begin, state = c = SLIP_NEUTRAL;
|
|
len < blen + 1; /* +1 for SLIP_END! */
|
|
) {
|
|
|
|
c = rxbuf[pos++];
|
|
|
|
if(pos == RX_BUFSIZE) {
|
|
/* Circular buffer: warp around */
|
|
pos = 0;
|
|
}
|
|
if(c == SLIP_END) {
|
|
/* End of packet */
|
|
break;
|
|
}
|
|
if(len >= blen) {
|
|
/* End of buffer with no SLIP_END
|
|
* ==> something wrong happened */
|
|
break;
|
|
}
|
|
switch(c) {
|
|
case SLIP_ESC:
|
|
state = SLIP_ESC;
|
|
break;
|
|
case SLIP_ESC_END:
|
|
if(state == SLIP_ESC) {
|
|
outbuf[len++] = SLIP_END;
|
|
state = SLIP_NEUTRAL;
|
|
} else {
|
|
outbuf[len++] = c;
|
|
} break;
|
|
case SLIP_ESC_ESC:
|
|
if(state == SLIP_ESC) {
|
|
outbuf[len++] = SLIP_ESC;
|
|
state = SLIP_NEUTRAL;
|
|
} else {
|
|
outbuf[len++] = c;
|
|
} break;
|
|
#if UART_XONXOFF_FLOW_CTRL
|
|
case SLIP_ESC_XON:
|
|
if(state == SLIP_ESC) {
|
|
outbuf[len++] = XON;
|
|
state = SLIP_NEUTRAL;
|
|
} else {
|
|
outbuf[len++] = c;
|
|
} break;
|
|
case SLIP_ESC_XOFF:
|
|
if(state == SLIP_ESC) {
|
|
outbuf[len++] = XOFF;
|
|
state = SLIP_NEUTRAL;
|
|
} else {
|
|
outbuf[len++] = c;
|
|
} break;
|
|
#endif /* UART_XONXOFF_FLOW_CTRL */
|
|
default:
|
|
outbuf[len++] = c;
|
|
state = SLIP_NEUTRAL;
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Update counters */
|
|
if(c == SLIP_END) {
|
|
ATOMIC(begin = pos;
|
|
if(end_counter) {
|
|
end_counter--;
|
|
}
|
|
)
|
|
PUTCHAR('P');
|
|
} else {
|
|
/* Something went wrong, no SLIP_END found, drop everything */
|
|
ATOMIC(rxbuf_init();
|
|
is_dropping = 1;
|
|
)
|
|
SLIP_STATISTICS(slip_error_drop++);
|
|
len = 0;
|
|
PRINTF("SLIP: *** out of sync!\n");
|
|
}
|
|
|
|
if(end_counter > 0) {
|
|
/* One more packet is buffered, need to be polled again! */
|
|
process_poll(&slip_process);
|
|
}
|
|
return len;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
PROCESS_THREAD(slip_process, ev, data)
|
|
{
|
|
PROCESS_BEGIN();
|
|
|
|
rxbuf_init();
|
|
|
|
while(1) {
|
|
PROCESS_YIELD_UNTIL(ev == PROCESS_EVENT_POLL);
|
|
|
|
/* Move packet from rxbuf to buffer provided by uIP. */
|
|
uip_len = slip_poll_handler(&uip_buf[UIP_LLH_LEN],
|
|
UIP_BUFSIZE - UIP_LLH_LEN);
|
|
|
|
PRINTF("SLIP: recv bytes %u frames RECV: %u. is_full %u, is_dropping %u.\n",
|
|
end_counter, uip_len, is_full, is_dropping);
|
|
|
|
/* We have free space now, resume slip RX */
|
|
if(is_full) {
|
|
is_full = 0;
|
|
ENABLE_UART_INTERRUPTS();
|
|
}
|
|
|
|
if(uip_len > 0) {
|
|
if(input_callback) {
|
|
input_callback();
|
|
}
|
|
#ifdef SLIP_CONF_TCPIP_INPUT
|
|
SLIP_CONF_TCPIP_INPUT();
|
|
#else
|
|
tcpip_input();
|
|
#endif
|
|
}
|
|
}
|
|
|
|
PROCESS_END();
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
/* Return status from slip_input_byte:
|
|
* -1 means RX buffer overflow ==> stop reading
|
|
* 0 means do not exit power saving mode
|
|
* 1 means exit power saving mode
|
|
**/
|
|
int
|
|
slip_input_byte(unsigned char c)
|
|
{
|
|
static int in_frame = 0;
|
|
uint16_t next, next_next;
|
|
int error_return_code = is_full ? -1 : 0;
|
|
int success_return_code = is_full ? -1 : 1;
|
|
|
|
SLIP_STATISTICS(slip_received++);
|
|
|
|
#if UART_XONXOFF_FLOW_CTRL
|
|
if(c == XOFF || c == XON) {
|
|
xonxoff_state = c;
|
|
return 1;
|
|
} else {
|
|
/* ANY char would be XON */
|
|
xonxoff_state = XON;
|
|
}
|
|
#endif /* UART_XONXOFF_FLOW_CTRL */
|
|
|
|
if(is_dropping) {
|
|
/* Make sure to drop full frames when overflow or
|
|
* out of sync happens */
|
|
if(c != SLIP_END) {
|
|
SLIP_STATISTICS(slip_drop_bytes++);
|
|
} else {
|
|
is_dropping = 0;
|
|
in_frame = 0;
|
|
}
|
|
return error_return_code;
|
|
}
|
|
|
|
if(!in_frame && c == SLIP_END) {
|
|
/* Ignore slip end when not receiving frame */
|
|
return error_return_code;
|
|
/* increment and wrap */
|
|
}
|
|
next = end + 1;
|
|
if(next >= RX_BUFSIZE) {
|
|
next = 0;
|
|
}
|
|
next_next = next + 1;
|
|
if(next_next >= RX_BUFSIZE) {
|
|
next_next = 0;
|
|
/* Next byte will overflow. Stop accepting. */
|
|
}
|
|
if(next_next == begin) {
|
|
is_full = 1;
|
|
/* disable UART interrupts */
|
|
DISABLE_UART_INTERRUPTS();
|
|
process_poll(&slip_process);
|
|
}
|
|
|
|
/* Buffer is full. We can't store anymore.
|
|
* Shall not happen normally,
|
|
* because of overflow protection above. */
|
|
if(next == begin) {
|
|
is_dropping = 1;
|
|
SLIP_STATISTICS(slip_overflow++);
|
|
is_full = 1;
|
|
/* disable UART interrupts */
|
|
DISABLE_UART_INTERRUPTS();
|
|
process_poll(&slip_process);
|
|
return -1;
|
|
}
|
|
|
|
rxbuf[end] = c;
|
|
end = next;
|
|
in_frame = 1;
|
|
|
|
if(c == SLIP_END) {
|
|
in_frame = 0;
|
|
end_counter++;
|
|
SLIP_STATISTICS(slip_frames++);
|
|
process_poll(&slip_process);
|
|
return success_return_code;
|
|
}
|
|
return error_return_code;
|
|
}
|
|
/*---------------------------------------------------------------------------*/
|
|
#if SLIP_BRIDGE_CONF_NO_PUTCHAR
|
|
int
|
|
putchar(int c)
|
|
{
|
|
uart0_writeb(c);
|
|
return 1;
|
|
}
|
|
#endif
|