xref: /btstack/src/classic/avrcp_media_item_iterator.c (revision e501bae08349e058caa4648e0af3dd01cbd89d20)

/*
 * Copyright (C) 2014 BlueKitchen GmbH
 *
 * 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 copyright holders nor the names of
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 * 4. Any redistribution, use, or modification is done solely for
 *    personal benefit and not for any commercial purpose or for
 *    monetary gain.
 *
 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH 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 MATTHIAS
 * RINGWALD 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.
 *
 * Please inquire about commercial licensing options at
 * [email protected]
 *
 */

#define BTSTACK_FILE__ "avrcp_media_item_iterator.c"


// *****************************************************************************
//
// AVRCP Media Item Iterator
//
// *****************************************************************************

#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "classic/avrcp_media_item_iterator.h"
#include "btstack_util.h"

void avrcp_media_item_iterator_init(avrcp_media_item_context_t *context, uint16_t avrcp_media_item_len, const uint8_t * avrcp_media_item_data){
    context->data = avrcp_media_item_data;
    context->length = avrcp_media_item_len;
    context->offset = 0;
}

int  avrcp_media_item_iterator_has_more(const avrcp_media_item_context_t * context){
    return context->offset < context->length;
}

void avrcp_media_item_iterator_next(avrcp_media_item_context_t * context){
    int chunk_len = big_endian_read_16(context->data, context->offset + 6);
    int new_offset = context->offset + 2 + 2 + 4 + chunk_len;
    // avoid uint8_t overrun
    if (new_offset > 0xffff){
        new_offset = 0xffff;
    }
    context->offset = new_offset;
}

uint32_t avrcp_media_item_iterator_get_attr_id(const avrcp_media_item_context_t * context){
    return big_endian_read_32(context->data, context->offset);
}

uint16_t avrcp_media_item_iterator_get_attr_charset(const avrcp_media_item_context_t * context){
    return big_endian_read_16(context->data, context->offset + 4);
}

uint16_t avrcp_media_item_iterator_get_attr_value_len(const avrcp_media_item_context_t * context){
    return big_endian_read_16(context->data, context->offset + 6);
}

const uint8_t * avrcp_media_item_iterator_get_attr_value(const avrcp_media_item_context_t * context){
    return &context->data[context->offset + 8];
}