decomp_list.h

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/*
 * Copyright 2013 Didier Barvaux
 * Copyright 2007,2008 Thales Alenia Space
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

/**
 * @file   schemes/decomp_list.h
 * @brief  ROHC generic list decompression
 * @author Didier Barvaux <didier@barvaux.org>
 */

#ifndef ROHC_DECOMP_LIST_H
#define ROHC_DECOMP_LIST_H

#include "rohc_list.h"
#include "rohc_traces_internal.h"


/** Print a warning trace for the given decompression list */
#define rd_list_warn(decomp_list, format, ...) \
        rohc_warning(decomp_list, ROHC_TRACE_DECOMP, (decomp_list)->profile_id, \
                     format, ##__VA_ARGS__)

/** Print a debug trace for the given decompression list */
#define rd_list_debug(decomp_list, format, ...) \
        rohc_debug(decomp_list, ROHC_TRACE_DECOMP, (decomp_list)->profile_id, \
                   format, ##__VA_ARGS__)


/**
 * @brief The context for list decompression
 *
 * The context contains a translation table that associates IDs and list
 * items together. The different lists (gen_id ones, reference one, anonymous
 * one) references the items from the translation table.
 */
struct list_decomp
{
        /** The translation table */
        struct rohc_list_item trans_table[ROHC_LIST_MAX_ITEM];

        /** All the possible named lists, indexed by gen_id */
        struct rohc_list lists[ROHC_LIST_GEN_ID_MAX + 1];

        /** The temporary packet list (not persistent across packets) */
        struct rohc_list pkt_list;


        /* Functions for handling the data to decompress */

        /** The handler used to check if the index corresponds to a valid item */
        bool (*check_item)(const struct list_decomp *const decomp,
                           const size_t index_table);

        /** The handler used to get the size of a list item */
        int (*get_item_size)(const uint8_t *data, const size_t data_len);

        /** The handler used to compare two items */
        rohc_list_item_cmp cmp_item;

        /** The handler used to create a list item */
        bool (*create_item)(const uint8_t *const data,
                            const size_t length,
                            const size_t index_table,
                            struct list_decomp *const decomp);

        /** The handler used to add the extension to IP packet */
        size_t (*build_uncomp_item)(const struct list_decomp *const decomp,
                                    const uint8_t ip_nh_type,
                                    uint8_t *const dest);


        /* Traces */

        /** The callback function used to manage traces */
        rohc_trace_callback2_t trace_callback;
        /** The private context of the callback function used to manage traces */
        void *trace_callback_priv;
        /** The profile ID the decompression list was created for */
        int profile_id;
};



/*
 * Generic list decompression
 */

int rohc_list_decode_maybe(struct list_decomp *const decomp,
                           const uint8_t *const packet,
                           const size_t packet_len)
        __attribute__((warn_unused_result, nonnull(1, 2)));

bool rohc_decomp_list_create_item(struct list_decomp *const decomp,
                                  const unsigned int xi_index,
                                  const unsigned int xi_index_value,
                                  const uint8_t *const rohc_packet,
                                  const size_t rohc_max_len,
                                  size_t *const item_length)
        __attribute__((warn_unused_result, nonnull(1, 4, 6)));

#endif