lowpan_context.h

00001 /*
00002  * Copyright (c) 2015-2017, Arm Limited and affiliates.
00003  * SPDX-License-Identifier: Apache-2.0
00004  *
00005  * Licensed under the Apache License, Version 2.0 (the "License");
00006  * you may not use this file except in compliance with the License.
00007  * You may obtain a copy of the License at
00008  *
00009  *     http://www.apache.org/licenses/LICENSE-2.0
00010  *
00011  * Unless required by applicable law or agreed to in writing, software
00012  * distributed under the License is distributed on an "AS IS" BASIS,
00013  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00014  * See the License for the specific language governing permissions and
00015  * limitations under the License.
00016  */
00017 
00018 /*
00019  * \file lowpan_context.h
00020  * \brief This header define API how contexts are saved and listed at interface side.
00021  *
00022  * API:
00023  *  * Add/Update context, lowpan_context_update()
00024  *  * Delete full list Context, lowpan_context_list_free()
00025  *  * Timeout update, protocol_6lowpan_context_timer()
00026  *
00027  */
00028 
00029 #ifndef LOWPAN_CONTEXT_DEFINE_H_
00030 #define LOWPAN_CONTEXT_DEFINE_H_
00031 #include "ns_list.h"
00032 
00033 /* Flags for decode or encode to context's information to 8-bit data from message or to message (cid_flags)*/
00034 #define LOWPAN_CONTEXT_C        0x10        // Compression
00035 #define LOWPAN_CONTEXT_CID_MASK 0x0F        // Context ID MASK
00036 #define LOWPAN_MAX_CONTEXT_COUNT 16
00037 
00038 typedef struct lowpan_context {
00039     uint32_t lifetime;      // Remaining lifetime (100ms ticks)
00040     unsigned length: 8;     // Context length
00041     unsigned cid: 4;        // Context Identifier
00042     bool    compression: 1; // C (Compression) flag
00043     bool    expiring: 1;    // True if main lifetime expired, pending deletion
00044     bool    stable: 1;      // Thread stable network data (always true if not Thread)
00045     uint8_t prefix[16];     // Context prefix
00046     ns_list_link_t link;
00047 } lowpan_context_t;
00048 
00049 typedef NS_LIST_HEAD (lowpan_context_t, link) lowpan_context_list_t;
00050 
00051 /**
00052  * \brief Update lowpan current context or add new one
00053  *
00054  * \param list pointer to linked list for context
00055  * \param cid_flags Define context id (LOWPAN_CONTEXT_CID_MASK) and Context compression mode (LOWPAN_CONTEXT_C)
00056  * \param lifetime in minutes for context 0 delete contexts
00057  * \param prefix pointer to context prefix
00058  * \param len prefin length in bits
00059  *
00060  * \return 0 Update OK
00061  * \return -2 Update fail Out of memory reason
00062  */
00063 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);
00064 
00065 /**
00066  * \brief Cleand free full linked list about context
00067  *
00068  * \param list pointer to linked list for context
00069  *
00070  */
00071 void lowpan_context_list_free(lowpan_context_list_t *list);
00072 
00073 /**
00074  * \brief Update lowpan context timeout ticks
00075  *
00076  * \param list pointer to linked list for context
00077  * \param ticks is in 1/10s
00078  *
00079  */
00080 void lowpan_context_timer(lowpan_context_list_t *list, uint_fast16_t ticks);
00081 /**
00082  * \brief Get Context entry from the list by context ID
00083  *
00084  * \param list pointer to linked list for context
00085  * \param id Define 4-bit context id LOWPAN_CONTEXT_CID_MASK
00086  *
00087  * \return >0 Pointer to Entry
00088  * \return NULL Not supported Context ID
00089  *
00090  */
00091 lowpan_context_t *lowpan_contex_get_by_id(const lowpan_context_list_t *list, uint8_t id);
00092 
00093 /**
00094  * \brief Get Longest match Context entry from the list for given IPv6 address
00095  *
00096  * \param list pointer to linked list for context
00097  * \param ipv6Address pointer to
00098  *
00099  * \return >0 Pointer to Entry
00100  * \return NULL Not supported Context for this address
00101  *
00102  */
00103 lowpan_context_t *lowpan_context_get_by_address(const lowpan_context_list_t *list, const uint8_t *ipv6Address);
00104 
00105 #endif /* LOWPAN_CONTEXT_DEFINE_H_ */