mbed-os/features/nanostack/sal-stack-nanostack/source/6LoWPAN/IPHC_Decode/lowpan_context.h

106 lines
3.6 KiB
C

/*
* Copyright (c) 2015-2017, Arm Limited and affiliates.
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* \file lowpan_context.h
* \brief This header define API how contexts are saved and listed at interface side.
*
* API:
* * Add/Update context, lowpan_context_update()
* * Delete full list Context, lowpan_context_list_free()
* * Timeout update, protocol_6lowpan_context_timer()
*
*/
#ifndef LOWPAN_CONTEXT_DEFINE_H_
#define LOWPAN_CONTEXT_DEFINE_H_
#include "ns_list.h"
/* Flags for decode or encode to context's information to 8-bit data from message or to message (cid_flags)*/
#define LOWPAN_CONTEXT_C 0x10 // Compression
#define LOWPAN_CONTEXT_CID_MASK 0x0F // Context ID MASK
#define LOWPAN_MAX_CONTEXT_COUNT 16
typedef struct lowpan_context {
uint32_t lifetime; // Remaining lifetime (100ms ticks)
unsigned length: 8; // Context length
unsigned cid: 4; // Context Identifier
bool compression: 1; // C (Compression) flag
bool expiring: 1; // True if main lifetime expired, pending deletion
bool stable: 1; // Thread stable network data (always true if not Thread)
uint8_t prefix[16]; // Context prefix
ns_list_link_t link;
} lowpan_context_t;
typedef NS_LIST_HEAD(lowpan_context_t, link) lowpan_context_list_t;
/**
* \brief Update lowpan current context or add new one
*
* \param list pointer to linked list for context
* \param cid_flags Define context id (LOWPAN_CONTEXT_CID_MASK) and Context compression mode (LOWPAN_CONTEXT_C)
* \param lifetime in minutes for context 0 delete contexts
* \param prefix pointer to context prefix
* \param len prefin length in bits
*
* \return 0 Update OK
* \return -2 Update fail Out of memory reason
*/
int_fast8_t lowpan_context_update(lowpan_context_list_t *list, uint8_t cid_flags, uint16_t lifetime, const uint8_t *prefix, uint_fast8_t len, bool stable);
/**
* \brief Cleand free full linked list about context
*
* \param list pointer to linked list for context
*
*/
void lowpan_context_list_free(lowpan_context_list_t *list);
/**
* \brief Update lowpan context timeout ticks
*
* \param list pointer to linked list for context
* \param ticks is in 1/10s
*
*/
void lowpan_context_timer(lowpan_context_list_t *list, uint_fast16_t ticks);
/**
* \brief Get Context entry from the list by context ID
*
* \param list pointer to linked list for context
* \param id Define 4-bit context id LOWPAN_CONTEXT_CID_MASK
*
* \return >0 Pointer to Entry
* \return NULL Not supported Context ID
*
*/
lowpan_context_t *lowpan_contex_get_by_id(const lowpan_context_list_t *list, uint8_t id);
/**
* \brief Get Longest match Context entry from the list for given IPv6 address
*
* \param list pointer to linked list for context
* \param ipv6Address pointer to
*
* \return >0 Pointer to Entry
* \return NULL Not supported Context for this address
*
*/
lowpan_context_t *lowpan_context_get_by_address(const lowpan_context_list_t *list, const uint8_t *ipv6Address);
#endif /* LOWPAN_CONTEXT_DEFINE_H_ */