nes-proj/os/net/packetbuf.c
2017-09-01 15:29:00 +02:00

238 lines
6.8 KiB
C

/*
* Copyright (c) 2006, 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.
*
*/
/**
* \file
* Packet buffer (packetbuf) management
* \author
* Adam Dunkels <adam@sics.se>
*/
/**
* \addtogroup packetbuf
* @{
*/
#include <string.h>
#include "contiki-net.h"
#include "net/packetbuf.h"
#include "sys/cc.h"
struct packetbuf_attr packetbuf_attrs[PACKETBUF_NUM_ATTRS];
struct packetbuf_addr packetbuf_addrs[PACKETBUF_NUM_ADDRS];
static uint16_t buflen, bufptr;
static uint8_t hdrlen;
/* The declarations below ensure that the packet buffer is aligned on
an even 32-bit boundary. On some platforms (most notably the
msp430 or OpenRISC), having a potentially misaligned packet buffer may lead to
problems when accessing words. */
static uint32_t packetbuf_aligned[(PACKETBUF_SIZE + 3) / 4];
static uint8_t *packetbuf = (uint8_t *)packetbuf_aligned;
#define DEBUG 0
#if DEBUG
#include <stdio.h>
#define PRINTF(...) printf(__VA_ARGS__)
#else
#define PRINTF(...)
#endif
/*---------------------------------------------------------------------------*/
void
packetbuf_clear(void)
{
buflen = bufptr = 0;
hdrlen = 0;
packetbuf_attr_clear();
}
/*---------------------------------------------------------------------------*/
int
packetbuf_copyfrom(const void *from, uint16_t len)
{
uint16_t l;
packetbuf_clear();
l = MIN(PACKETBUF_SIZE, len);
memcpy(packetbuf, from, l);
buflen = l;
return l;
}
/*---------------------------------------------------------------------------*/
int
packetbuf_copyto(void *to)
{
if(hdrlen + buflen > PACKETBUF_SIZE) {
return 0;
}
memcpy(to, packetbuf_hdrptr(), hdrlen);
memcpy((uint8_t *)to + hdrlen, packetbuf_dataptr(), buflen);
return hdrlen + buflen;
}
/*---------------------------------------------------------------------------*/
int
packetbuf_hdralloc(int size)
{
int16_t i;
if(size + packetbuf_totlen() > PACKETBUF_SIZE) {
return 0;
}
/* shift data to the right */
for(i = packetbuf_totlen() - 1; i >= 0; i--) {
packetbuf[i + size] = packetbuf[i];
}
hdrlen += size;
return 1;
}
/*---------------------------------------------------------------------------*/
int
packetbuf_hdrreduce(int size)
{
if(buflen < size) {
return 0;
}
bufptr += size;
buflen -= size;
return 1;
}
/*---------------------------------------------------------------------------*/
void
packetbuf_set_datalen(uint16_t len)
{
PRINTF("packetbuf_set_len: len %d\n", len);
buflen = len;
}
/*---------------------------------------------------------------------------*/
void *
packetbuf_dataptr(void)
{
return packetbuf + packetbuf_hdrlen();
}
/*---------------------------------------------------------------------------*/
void *
packetbuf_hdrptr(void)
{
return packetbuf;
}
/*---------------------------------------------------------------------------*/
uint16_t
packetbuf_datalen(void)
{
return buflen;
}
/*---------------------------------------------------------------------------*/
uint8_t
packetbuf_hdrlen(void)
{
return bufptr + hdrlen;
}
/*---------------------------------------------------------------------------*/
uint16_t
packetbuf_totlen(void)
{
return packetbuf_hdrlen() + packetbuf_datalen();
}
/*---------------------------------------------------------------------------*/
uint16_t
packetbuf_remaininglen(void)
{
return PACKETBUF_SIZE - packetbuf_totlen();
}
/*---------------------------------------------------------------------------*/
void
packetbuf_attr_clear(void)
{
int i;
memset(packetbuf_attrs, 0, sizeof(packetbuf_attrs));
for(i = 0; i < PACKETBUF_NUM_ADDRS; ++i) {
linkaddr_copy(&packetbuf_addrs[i].addr, &linkaddr_null);
}
}
/*---------------------------------------------------------------------------*/
void
packetbuf_attr_copyto(struct packetbuf_attr *attrs,
struct packetbuf_addr *addrs)
{
memcpy(attrs, packetbuf_attrs, sizeof(packetbuf_attrs));
memcpy(addrs, packetbuf_addrs, sizeof(packetbuf_addrs));
}
/*---------------------------------------------------------------------------*/
void
packetbuf_attr_copyfrom(struct packetbuf_attr *attrs,
struct packetbuf_addr *addrs)
{
memcpy(packetbuf_attrs, attrs, sizeof(packetbuf_attrs));
memcpy(packetbuf_addrs, addrs, sizeof(packetbuf_addrs));
}
/*---------------------------------------------------------------------------*/
int
packetbuf_set_attr(uint8_t type, const packetbuf_attr_t val)
{
packetbuf_attrs[type].val = val;
return 1;
}
/*---------------------------------------------------------------------------*/
packetbuf_attr_t
packetbuf_attr(uint8_t type)
{
return packetbuf_attrs[type].val;
}
/*---------------------------------------------------------------------------*/
int
packetbuf_set_addr(uint8_t type, const linkaddr_t *addr)
{
linkaddr_copy(&packetbuf_addrs[type - PACKETBUF_ADDR_FIRST].addr, addr);
return 1;
}
/*---------------------------------------------------------------------------*/
const linkaddr_t *
packetbuf_addr(uint8_t type)
{
return &packetbuf_addrs[type - PACKETBUF_ADDR_FIRST].addr;
}
/*---------------------------------------------------------------------------*/
int
packetbuf_holds_broadcast(void)
{
return linkaddr_cmp(&packetbuf_addrs[PACKETBUF_ADDR_RECEIVER - PACKETBUF_ADDR_FIRST].addr, &linkaddr_null);
}
/*---------------------------------------------------------------------------*/
/** @} */