/*
 * Copyright (c) 2014-2015 ARM Limited. All rights reserved.
 * 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.
 */
#ifndef IP6STRING_H
#define IP6STRING_H
#ifdef __cplusplus
extern "C" {
#endif

#include "ns_types.h"

#define MAX_IPV6_STRING_LEN_WITH_TRAILING_NULL 40

/**
 * Print binary IPv6 address to a string.
 *
 * String must contain enough room for full address, 40 bytes exact.
 * IPv4 tunneling addresses are not covered.
 *
 * \param ip6addr IPv6 address.
 * \param p buffer to write string to.
 * \return length of generated string excluding the terminating null character
 */
uint_fast8_t ip6tos(const void *ip6addr, char *p);

/**
 * Print binary IPv6 prefix to a string.
 *
 * String buffer `p` must contain enough room for a full address and prefix length, 44 bytes exact.
 * Bits in the `prefix` buffer beyond `prefix_len` bits are not shown and only the bytes containing the
 * prefix bits are read. I.e. for a 20 bit prefix 3 bytes are read, and for a 0 bit prefix 0 bytes are
 * read (thus if `prefix_len` is zero, `prefix` can be NULL).
 * `prefix_len` must be 0 to 128.
 *
 * \param prefix IPv6 prefix.
 * \param prefix_len length of `prefix` in bits.
 * \param p buffer to write string to.
 * \return length of generated string excluding the terminating null character, or 0 for an error, such as 'prefix_len' > 128
 */
uint_fast8_t ip6_prefix_tos(const void *prefix, uint_fast8_t prefix_len, char *p);

/**
 * Convert numeric IPv6 address string to a binary.
 *
 * IPv4 tunneling addresses are not covered.
 *
 * \param ip6addr IPv6 address in string format.
 * \param len Lenght of ipv6 string, maximum of 41.
 * \param dest buffer for address. MUST be 16 bytes. Filled with 0 on error.
 * \return boolean set to true if conversion succeed, false if it didn't
 */
bool stoip6(const char *ip6addr, size_t len, void *dest);
/**
 * Find out numeric IPv6 address prefix length.
 *
 * \param ip6addr  IPv6 address in string format
 * \return prefix length or 0 if it not given
 */
unsigned char sipv6_prefixlength(const char *ip6addr);

/**
 * Convert numeric IPv6 address string with prefix to a binary.
 *
 * IPv4 tunneling addresses are not covered.
 *
 * \param ip6addr IPv6 address in string format.
 * \param dest buffer for address. MUST be 16 bytes.
 * \param prefix_len_out length of prefix, is set to -1 if no prefix given
 *
 * \return 0 on success, negative value otherwise. prefix_len_out contains prefix length.
  */
int stoip6_prefix(const char *ip6addr, void *dest, int_fast16_t *prefix_len_out);

#ifdef __cplusplus
}
#endif
#endif
