获取特征值句柄问题

确实是通过底层callback函数传递的，主机发现服务后，可以通过特征值的UUID获取到特征值的句柄

static bStatus_t simpleProfile_ReadAttrCB(uint16_t connHandle,
                                          gattAttribute_t *pAttr,
                                          uint8_t *pValue, uint16_t *pLen,
                                          uint16_t offset, uint16_t maxLen,
                                          uint8_t method)
{
  bStatus_t status = SUCCESS;

  // Make sure it's not a blob operation (no attributes in the profile are long)
  if ( offset > 0 )
  {
    return ( ATT_ERR_ATTR_NOT_LONG );
  }

  if ( pAttr->type.len == ATT_BT_UUID_SIZE )
  {
    // 16-bit UUID
    uint16 uuid = BUILD_UINT16( pAttr->type.uuid[0], pAttr->type.uuid[1]);
    switch ( uuid )
    {
      // No need for "GATT_SERVICE_UUID" or "GATT_CLIENT_CHAR_CFG_UUID" cases;
      // gattserverapp handles those reads

      // characteristics 1 and 2 have read permissions
      // characteritisc 3 does not have read permissions; therefore it is not
      //   included here
      // characteristic 4 does not have read permissions, but because it
      //   can be sent as a notification, it is included here
      case SIMPLEPROFILE_CHAR1_UUID:
      case SIMPLEPROFILE_CHAR2_UUID:
      case SIMPLEPROFILE_CHAR4_UUID:
        *pLen = 1;
        pValue[0] = *pAttr->pValue;
        break;

      case SIMPLEPROFILE_CHAR5_UUID:
        *pLen = SIMPLEPROFILE_CHAR5_LEN;
        VOID memcpy( pValue, pAttr->pValue, SIMPLEPROFILE_CHAR5_LEN );
        break;

      default:
        // Should never get here! (characteristics 3 and 4 do not have read permissions)
        *pLen = 0;
        status = ATT_ERR_ATTR_NOT_FOUND;
        break;
    }
  }
  else
  {
    // 128-bit UUID
    *pLen = 0;
    status = ATT_ERR_INVALID_HANDLE;
  }

  return ( status );
}