btcore/src/bdaddr.c

/******************************************************************************
 *
 *  Copyright (C) 2014 Google, Inc.
 *
 *  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.
 *
 ******************************************************************************/

#include <assert.h>
#include <ctype.h>
#include <stdio.h>
#include <string.h>

#include "btcore/include/bdaddr.h"

bool bdaddr_is_empty(const bt_bdaddr_t *addr) {
  assert(addr != NULL);

  uint8_t zero[sizeof(bt_bdaddr_t)] = { 0 };
  return memcmp(addr, &zero, sizeof(bt_bdaddr_t)) == 0;
}

bool bdaddr_equals(const bt_bdaddr_t *first, const bt_bdaddr_t *second) {
  assert(first != NULL);
  assert(second != NULL);

  return memcmp(first, second, sizeof(bt_bdaddr_t)) == 0;
}

bt_bdaddr_t *bdaddr_copy(bt_bdaddr_t *dest, const bt_bdaddr_t *src) {
  assert(dest != NULL);
  assert(src != NULL);

  return (bt_bdaddr_t *)memcpy(dest, src, sizeof(bt_bdaddr_t));
}

const char *bdaddr_to_string(const bt_bdaddr_t *addr, char *string, size_t size) {
  assert(addr != NULL);
  assert(string != NULL);

  if (size < 18)
    return NULL;

  const uint8_t *ptr = addr->address;
  sprintf(string, "%02x:%02x:%02x:%02x:%02x:%02x",
           ptr[0], ptr[1], ptr[2],
           ptr[3], ptr[4], ptr[5]);
  return string;
}

bool string_is_bdaddr(const char *string) {
  assert(string != NULL);

  size_t len = strlen(string);
  if (len != 17)
    return false;

  for (size_t i = 0; i < len; ++i) {
    // Every 3rd char must be ':'.
    if (((i + 1) % 3) == 0 && string[i] != ':')
      return false;

    // All other chars must be a hex digit.
    if (((i + 1) % 3) != 0 && !isxdigit(string[i]))
      return false;
  }
  return true;
}

bool string_to_bdaddr(const char *string, bt_bdaddr_t *addr) {
  assert(string != NULL);
  assert(addr != NULL);

  bt_bdaddr_t new_addr;
  uint8_t *ptr = new_addr.address;
  bool ret = sscanf(string, "%02hhx:%02hhx:%02hhx:%02hhx:%02hhx:%02hhx",
      &ptr[0], &ptr[1], &ptr[2], &ptr[3], &ptr[4], &ptr[5]) == 6;

  if (ret)
    memcpy(addr, &new_addr, sizeof(bt_bdaddr_t));

  return ret;
}

hash_index_t hash_function_bdaddr(const void *key) {
  hash_index_t hash = 5381;
  const char *bytes = (const char *)key;
  for (size_t i = 0; i < sizeof(bt_bdaddr_t); ++i)
    hash = ((hash << 5) + hash) + bytes[i];
  return hash;
}