contiki/core/net/rime/chameleon-bitopt.c
nifi f6e0b46f38 * Made Chameleon header processing module configurable (CHAMELEON_CONF_MODULE)
* Removed the unused init function from header processing modules
* Added option CHAMELEON_CONF_WITH_MAC_LINK_ADDRESSES to specify that
  MAC link addresses should be used instead of Chameleon's own encoding
  of sender and receiver. This avoids encoding the link addresses twice
  when the MAC RDC has its own addresses.
2010-05-28 06:18:39 +00:00

378 lines
12 KiB
C

/*
* Copyright (c) 2007, 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.
*
* $Id: chameleon-bitopt.c,v 1.9 2010/05/28 06:18:39 nifi Exp $
*/
/**
* \file
* A Chameleon module that produces bit-optimized headers
* \author
* Adam Dunkels <adam@sics.se>
*/
#include "net/rime/chameleon.h"
#include "net/rime.h"
#include <string.h>
/* This option enables an optimization where the link addresses are
left to the MAC RDC and not encoded in the Chameleon header.
Note: this requires that the underlying MAC layer to add link
addresses and will not work together with for example nullrdc.
*/
#ifdef CHAMELEON_CONF_WITH_MAC_LINK_ADDRESSES
#define CHAMELEON_WITH_MAC_LINK_ADDRESSES CHAMELEON_CONF_WITH_MAC_LINK_ADDRESSES
#else /* !CHAMELEON_CONF_WITH_MAC_LINK_ADDRESSES */
#define CHAMELEON_WITH_MAC_LINK_ADDRESSES 0
#endif /* !CHAMELEON_CONF_WITH_MAC_LINK_ADDRESSES */
struct bitopt_hdr {
uint8_t channel[2];
};
static const uint8_t bitmask[9] = { 0x00, 0x80, 0xc0, 0xe0, 0xf0,
0xf8, 0xfc, 0xfe, 0xff };
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif
/*---------------------------------------------------------------------------*/
uint8_t CC_INLINE
get_bits_in_byte(uint8_t *from, int bitpos, int vallen)
{
uint16_t shifted_val;
shifted_val = (from[0] << 8) | from[1];
/* PRINTF("get_bits_in_byte: from[0] 0x%02x from[1] 0x%02x shifted_val 0x%04x, return 0x%02x vallen %d\n",
from[0], from[1], shifted_val,
(((shifted_val << bitpos) >> 8) & bitmask[vallen]) >> (8 - vallen),
vallen
);*/
return (((shifted_val << bitpos) >> 8) & bitmask[vallen]) >> (8 - vallen);
}
/*---------------------------------------------------------------------------*/
void
get_bits(uint8_t *to, uint8_t *from, int bitpos, int vallen)
{
int i, bits;
if(vallen < 8) {
*to = get_bits_in_byte(from, bitpos, vallen);
} else {
if(bitpos == 0) {
for(i = 0; i < vallen / 8; ++i) {
/* PRINTF("get_bits i %d val 0x%02x\n",
i, from[i]);*/
to[i] = from[i];
}
bits = vallen & 7;
if(bits) {
to[i] = get_bits_in_byte(&from[i], 0, bits);
}
} else {
for(i = 0; i < vallen / 8; ++i) {
/* PRINTF("get_bits i %d val 0x%02x bitpos %d\n",
i, from[i], bitpos);*/
to[i] = get_bits_in_byte(&from[i], bitpos, 8);
}
bits = vallen & 7;
if(bits) {
to[i] = get_bits_in_byte(&from[i], bitpos, bits);
}
}
}
}
/*---------------------------------------------------------------------------*/
static int
header_size(const struct packetbuf_attrlist *a)
{
int size, len;
/* Compute the total size of the final header by summing the size of
all attributes that are used on this channel. */
size = 0;
for(; a->type != PACKETBUF_ATTR_NONE; ++a) {
#if CHAMELEON_WITH_MAC_LINK_ADDRESSES
if(a->type == PACKETBUF_ADDR_SENDER ||
a->type == PACKETBUF_ADDR_RECEIVER) {
/* Let the link layer handle sender and receiver */
continue;
}
#endif /* CHAMELEON_WITH_MAC_LINK_ADDRESSES */
/* PRINTF("chameleon header_size: header type %s (%d) len %d\n",
packetbuf_attr_strings[a->type],
a->type,
a->len);*/
len = a->len;
/* if(len < 8) {
len = 8;
}*/
size += len;
}
return size;
}
/*---------------------------------------------------------------------------*/
void CC_INLINE
set_bits_in_byte(uint8_t *target, int bitpos, uint8_t val, int vallen)
{
unsigned short shifted_val;
shifted_val = val << (8 - bitpos + 8 - vallen);
/* printf("set_bits_in_byte before target[0] 0x%02x target[1] 0x%02x shifted_val 0x%04x val 0x%02x vallen %d\n",
target[0], target[1], shifted_val, val, vallen);*/
target[0] |= shifted_val >> 8;
target[1] |= shifted_val & 0xff;
}
/*---------------------------------------------------------------------------*/
void
set_bits(uint8_t *ptr, int bitpos, uint8_t *val, int vallen)
{
int i, bits;
/* PRINTF("set_bits %p bitpos %d, val %p len %d\n",
ptr, bitpos, val, vallen);*/
if(vallen < 8) {
set_bits_in_byte(ptr, bitpos, *val /*>> (8 - vallen)*/, vallen);
} else {
if(bitpos == 0) {
for(i = 0; i < vallen / 8; ++i) {
/* PRINTF("set_bits i %d val %d\n",
i, val[i]);*/
ptr[i] = val[i];
}
bits = vallen & 7;
if(bits) {
set_bits_in_byte(&ptr[i], 0, val[i] >> (8 - bits), bits);
}
} else {
for(i = 0; i < vallen / 8; ++i) {
/* PRINTF("set_bits i %d val %d\n",
i, val[i]);*/
set_bits_in_byte(&ptr[i], bitpos, val[i], 8);
}
bits = vallen & 7;
if(bits) {
set_bits_in_byte(&ptr[i], 0, val[i] >> (8 - bits + bitpos), bits);
}
}
}
}
/*---------------------------------------------------------------------------*/
#if 0
static void
printbin(int n, int digits)
{
int i;
char output[128];
for(i = 0; i < digits; ++i) {
output[digits - i - 1] = (n & 1) + '0';
n >>= 1;
}
output[i] = 0;
printf(output);
}
static void
printhdr(uint8_t *hdr, int len)
{
int i, j;
j = 0;
for(i = 0; i < len; ++i) {
printbin(hdr[i], 8);
printf(", ");
++j;
if(j == 10) {
printf("\n");
j = 0;
}
}
if(j != 0) {
printf("\n");
}
}
#endif
/*---------------------------------------------------------------------------*/
static int
pack_header(struct channel *c)
{
const struct packetbuf_attrlist *a;
int hdrbytesize;
int byteptr, bitptr, len;
uint8_t *hdrptr;
struct bitopt_hdr *hdr;
/* Compute the total size of the final header by summing the size of
all attributes that are used on this channel. */
hdrbytesize = c->hdrsize / 8 + ((c->hdrsize & 7) == 0? 0: 1);
if(packetbuf_hdralloc(hdrbytesize + sizeof(struct bitopt_hdr)) == 0) {
PRINTF("chameleon-bitopt: insufficient space for headers\n");
return 0;
}
hdr = (struct bitopt_hdr *)packetbuf_hdrptr();
hdr->channel[0] = c->channelno & 0xff;
hdr->channel[1] = (c->channelno >> 8) & 0xff;
hdrptr = ((uint8_t *)packetbuf_hdrptr()) + sizeof(struct bitopt_hdr);
memset(hdrptr, 0, hdrbytesize);
byteptr = bitptr = 0;
for(a = c->attrlist; a->type != PACKETBUF_ATTR_NONE; ++a) {
#if CHAMELEON_WITH_MAC_LINK_ADDRESSES
if(a->type == PACKETBUF_ADDR_SENDER ||
a->type == PACKETBUF_ADDR_RECEIVER) {
/* Let the link layer handle sender and receiver */
PRINTF("%d.%d: pack_header leaving sender/receiver to link layer\n");
continue;
}
#endif /* CHAMELEON_WITH_MAC_LINK_ADDRESSES */
PRINTF("%d.%d: pack_header type %s, len %d, bitptr %d, ",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
packetbuf_attr_strings[a->type], a->len, bitptr);
/* len = (a->len & 0xf8) + ((a->len & 7) ? 8: 0);*/
len = a->len;
byteptr = bitptr / 8;
if(PACKETBUF_IS_ADDR(a->type)) {
set_bits(&hdrptr[byteptr], bitptr & 7,
(uint8_t *)packetbuf_addr(a->type), len);
PRINTF("address %d.%d\n",
/* rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],*/
((uint8_t *)packetbuf_addr(a->type))[0],
((uint8_t *)packetbuf_addr(a->type))[1]);
} else {
packetbuf_attr_t val;
val = packetbuf_attr(a->type);
set_bits(&hdrptr[byteptr], bitptr & 7,
(uint8_t *)&val, len);
PRINTF("value %d\n",
/*rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],*/
val);
}
/* printhdr(hdrptr, hdrbytesize);*/
bitptr += len;
}
/* printhdr(hdrptr, hdrbytesize);*/
return 1; /* Send out packet */
}
/*---------------------------------------------------------------------------*/
static struct channel *
unpack_header(void)
{
const struct packetbuf_attrlist *a;
int byteptr, bitptr, len;
int hdrbytesize;
uint8_t *hdrptr;
struct bitopt_hdr *hdr;
struct channel *c;
/* The packet has a header that tells us what channel the packet is
for. */
hdr = (struct bitopt_hdr *)packetbuf_dataptr();
if(packetbuf_hdrreduce(sizeof(struct bitopt_hdr)) == 0) {
PRINTF("chameleon-bitopt: too short packet\n");
return NULL;
}
c = channel_lookup((hdr->channel[1] << 8) + hdr->channel[0]);
if(c == NULL) {
PRINTF("chameleon-bitopt: input: channel %u not found\n",
(hdr->channel[1] << 8) + hdr->channel[0]);
return NULL;
}
hdrptr = packetbuf_dataptr();
hdrbytesize = c->hdrsize / 8 + ((c->hdrsize & 7) == 0? 0: 1);
if(packetbuf_hdrreduce(hdrbytesize) == 0) {
PRINTF("chameleon-bitopt: too short packet\n");
return NULL;
}
byteptr = bitptr = 0;
for(a = c->attrlist; a->type != PACKETBUF_ATTR_NONE; ++a) {
#if CHAMELEON_WITH_MAC_LINK_ADDRESSES
if(a->type == PACKETBUF_ADDR_SENDER ||
a->type == PACKETBUF_ADDR_RECEIVER) {
/* Let the link layer handle sender and receiver */
continue;
}
#endif /* CHAMELEON_WITH_MAC_LINK_ADDRESSES */
PRINTF("%d.%d: unpack_header type %s, len %d, bitptr %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
packetbuf_attr_strings[a->type], a->len, bitptr);
/* len = (a->len & 0xf8) + ((a->len & 7) ? 8: 0);*/
len = a->len;
byteptr = bitptr / 8;
if(PACKETBUF_IS_ADDR(a->type)) {
rimeaddr_t addr;
get_bits((uint8_t *)&addr, &hdrptr[byteptr], bitptr & 7, len);
PRINTF("%d.%d: unpack_header type %s, addr %d.%d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
packetbuf_attr_strings[a->type],
addr.u8[0], addr.u8[1]);
packetbuf_set_addr(a->type, &addr);
} else {
packetbuf_attr_t val = 0;
get_bits((uint8_t *)&val, &hdrptr[byteptr], bitptr & 7, len);
packetbuf_set_attr(a->type, val);
PRINTF("%d.%d: unpack_header type %s, val %d\n",
rimeaddr_node_addr.u8[0], rimeaddr_node_addr.u8[1],
packetbuf_attr_strings[a->type],
val);
}
/* byteptr += len / 8;*/
bitptr += len;
}
return c;
}
/*---------------------------------------------------------------------------*/
CC_CONST_FUNCTION struct chameleon_module chameleon_bitopt = {
unpack_header,
pack_header,
header_size
};
/*---------------------------------------------------------------------------*/