mbed-os/libraries/ble/nRF51822/btle/custom/custom_helper.cpp

/* mbed Microcontroller Library
 * Copyright (c) 2006-2013 ARM Limited
 *
 * 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 "custom_helper.h"

/**************************************************************************/
/*!
    @brief      Adds the base UUID to the custom service. All UUIDs used
                by this service are based on this 128-bit UUID.
                
    @note       This UUID needs to be added to the SoftDevice stack before
                adding the service's primary service via
                'sd_ble_gatts_service_add'

    @param[in]  p_uuid_base   A pointer to the 128-bit UUID array (8*16)
    
    @returns    The UUID type.
                A return value of 0 should be considered an error.
                
    @retval     0x00    BLE_UUID_TYPE_UNKNOWN
    @retval     0x01    BLE_UUID_TYPE_BLE
    @retval     0x02    BLE_UUID_TYPE_VENDOR_BEGIN
    
    @section EXAMPLE
    @code

    // Take note that bytes 2/3 are blank since these are used to identify
    // the primary service and individual characteristics
    #define CFG_CUSTOM_UUID_BASE  "\x6E\x40\x00\x00\xB5\xA3\xF3\x93\xE0\xA9\xE5\x0E\x24\xDC\xCA\x9E"
    
    uint8_t uuid_type = custom_add_uuid_base(CFG_CUSTOM_UUID_BASE);
    ASSERT(uuid_type > 0, ERROR_NOT_FOUND);
    
    // We can now safely add the primary service and any characteristics
    // for our custom service ...
    
    @endcode
*/
/**************************************************************************/
uint8_t custom_add_uuid_base(uint8_t const * const p_uuid_base)
{
  ble_uuid128_t base_uuid;
  uint8_t uuid_type = 0;

  /* Reverse the bytes since ble_uuid128_t is LSB */
  for(uint8_t i=0; i<16; i++)
  {
    base_uuid.uuid128[i] = p_uuid_base[15-i];
  }

  ASSERT_INT( ERROR_NONE, sd_ble_uuid_vs_add( &base_uuid, &uuid_type ), 0);

  return uuid_type;
}

/**************************************************************************/
/*!

*/
/**************************************************************************/
error_t custom_decode_uuid_base(uint8_t const * const p_uuid_base, ble_uuid_t * p_uuid)
{
  uint8_t uuid_base_le[16];

  /* Reverse the bytes since ble_uuid128_t is LSB */
  for(uint8_t i=0; i<16; i++)
  {
    uuid_base_le[i] = p_uuid_base[15-i];
  }

  ASSERT_STATUS( sd_ble_uuid_decode(16, uuid_base_le, p_uuid) );

  return ERROR_NONE;
}

/**************************************************************************/
/*!
    @brief      Adds a new characteristic to the custom service, assigning
                properties, a UUID add-on value, etc.

    @param[in]  service_handle
    @param[in]  p_uuid            The 16-bit value to add to the base UUID
                                  for this characteristic (normally >1
                                  since 1 is typically used by the primary
                                  service).
    @param[in]  char_props        The characteristic properties, as
                                  defined by ble_gatt_char_props_t
    @param[in]  max_length        The maximum length of this characeristic
    @param[in]  p_char_handle
    
    @returns
    @retval     ERROR_NONE        Everything executed normally
*/
/**************************************************************************/
error_t custom_add_in_characteristic(uint16_t service_handle, ble_uuid_t* p_uuid, uint8_t properties,
                                     uint8_t *p_data, uint16_t min_length, uint16_t max_length,
                                     ble_gatts_char_handles_t* p_char_handle)
{
  /* Characteristic metadata */
  ble_gatts_attr_md_t cccd_md;
  ble_gatt_char_props_t char_props;

  memcpy(&char_props, &properties, 1);

  if ( char_props.notify || char_props.indicate )
  { 
    /* Notification requires cccd */
    memclr_( &cccd_md, sizeof(ble_gatts_attr_md_t) );
    cccd_md.vloc = BLE_GATTS_VLOC_STACK;
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.read_perm);
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&cccd_md.write_perm);
  }

  ble_gatts_char_md_t char_md = { 0 };

  char_md.char_props = char_props;
  char_md.p_cccd_md  = (char_props.notify || char_props.indicate ) ? &cccd_md : NULL;

  /* Attribute declaration */
  ble_gatts_attr_md_t attr_md = { 0 };

  attr_md.vloc = BLE_GATTS_VLOC_STACK;
  attr_md.vlen = (min_length == max_length) ? 0 : 1;

  if ( char_props.read || char_props.notify || char_props.indicate )
  {
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.read_perm);
  }

  if ( char_props.write )
  {
    BLE_GAP_CONN_SEC_MODE_SET_OPEN(&attr_md.write_perm);
  }

  ble_gatts_attr_t    attr_char_value = { 0 };

  attr_char_value.p_uuid    = p_uuid;
  attr_char_value.p_attr_md = &attr_md;
  attr_char_value.init_len  = min_length;
  attr_char_value.max_len   = max_length;
  attr_char_value.p_value   = p_data;


  ASSERT_STATUS ( sd_ble_gatts_characteristic_add(service_handle,
                                                  &char_md,
                                                  &attr_char_value,
                                                  p_char_handle) );

  return ERROR_NONE;
}