/*
* 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
* contact@bluekitchen-gmbh.com
*
*/
#define BTSTACK_FILE__ "le_data_channel_server.c"
// *****************************************************************************
/* EXAMPLE_START(le_data_channel): LE Data Channel Server - Receive data over L2CAP
*
* @text iOS 11 and newer supports LE Data Channels for fast transfer over LE
* [https://github.com/bluekitchen/CBL2CAPChannel-Demo](Basic iOS example on GitHub)
*/
// *****************************************************************************
#include <inttypes.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "btstack.h"
#include "le_data_channel_server.h"
// #define TEST_STREAM_DATA
#define TEST_PACKET_SIZE 1000
#define REPORT_INTERVAL_MS 3000
#define MAX_NR_CONNECTIONS 3
const uint16_t TSPX_le_psm = 0x25;
static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
static void sm_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
const uint8_t adv_data[] = {
// Flags general discoverable, BR/EDR not supported
0x02, 0x01, 0x06,
// Name
0x10, 0x09, 'L', 'E', ' ', 'D', 'a', 't', 'a', ' ', 'C', 'h', 'a', 'n', 'n', 'e', 'l',
};
const uint8_t adv_data_len = sizeof(adv_data);
static btstack_packet_callback_registration_t event_callback_registration;
static btstack_packet_callback_registration_t sm_event_callback_registration;
// support for multiple clients
typedef struct {
char name;
hci_con_handle_t connection_handle;
uint16_t cid;
int counter;
char test_data[TEST_PACKET_SIZE];
int test_data_len;
uint32_t test_data_sent;
uint32_t test_data_start;
} le_data_channel_connection_t;
static le_data_channel_connection_t le_data_channel_connection;
static uint16_t initial_credits = L2CAP_LE_AUTOMATIC_CREDITS;
static uint8_t data_channel_buffer[TEST_PACKET_SIZE];
/* @section Main Application Setup
*
* @text Listing MainConfiguration shows main application code.
* It initializes L2CAP, the Security Manager, and configures the ATT Server with the pre-compiled
* ATT Database generated from $le_data_channel.gatt$. Finally, it configures the advertisements
* and boots the Bluetooth stack.
*/
/* LISTING_START(MainConfiguration): Init L2CAP, SM, ATT Server, and enable advertisements */
static void le_data_channel_setup(void){
l2cap_init();
// setup le device db
le_device_db_init();
// setup SM: Display only
sm_init();
// setup ATT server: iOS disconnects if ATT MTU Exchange fails
att_server_init(profile_data, NULL, NULL);
// register for HCI events
event_callback_registration.callback = &packet_handler;
hci_add_event_handler(&event_callback_registration);
// register for SM events
sm_event_callback_registration.callback = &sm_packet_handler;
sm_add_event_handler(&sm_event_callback_registration);
l2cap_register_packet_handler(&packet_handler);
// le data channel setup
l2cap_le_register_service(&packet_handler, TSPX_le_psm, LEVEL_0);
// setup advertisements
uint16_t adv_int_min = 0x0030;
uint16_t adv_int_max = 0x0030;
uint8_t adv_type = 0;
bd_addr_t null_addr;
memset(null_addr, 0, 6);
gap_advertisements_set_params(adv_int_min, adv_int_max, adv_type, 0, null_addr, 0x07, 0x00);
gap_advertisements_set_data(adv_data_len, (uint8_t*) adv_data);
gap_advertisements_enable(1);
}
/* LISTING_END */
/*
* @section Track throughput
* @text We calculate the throughput by setting a start time and measuring the amount of
* data sent. After a configurable REPORT_INTERVAL_MS, we print the throughput in kB/s
* and reset the counter and start time.
*/
/* LISTING_START(tracking): Tracking throughput */
static void test_reset(le_data_channel_connection_t * context){
context->test_data_start = btstack_run_loop_get_time_ms();
context->test_data_sent = 0;
}
static void test_track_data(le_data_channel_connection_t * context, int bytes_transferred){
context->test_data_sent += bytes_transferred;
// evaluate
uint32_t now = btstack_run_loop_get_time_ms();
uint32_t time_passed = now - context->test_data_start;
if (time_passed < REPORT_INTERVAL_MS) return;
// print speed
int bytes_per_second = context->test_data_sent * 1000 / time_passed;
printf("%c: %"PRIu32" bytes sent-> %u.%03u kB/s\n", context->name, context->test_data_sent, bytes_per_second / 1000, bytes_per_second % 1000);
// restart
context->test_data_start = now;
context->test_data_sent = 0;
}
/* LISTING_END(tracking): Tracking throughput */
#ifdef TEST_STREAM_DATA
/* LISTING_END */
/*
* @section Streamer
*
* @text The streamer function checks if notifications are enabled and if a notification can be sent now.
* It creates some test data - a single letter that gets increased every time - and tracks the data sent.
*/
/* LISTING_START(streamer): Streaming code */
static void streamer(void){
if (le_data_channel_connection.cid == 0) return;
// create test data
le_data_channel_connection.counter++;
if (le_data_channel_connection.counter > 'Z') le_data_channel_connection.counter = 'A';
memset(le_data_channel_connection.test_data, le_data_channel_connection.counter, le_data_channel_connection.test_data_len);
// send
l2cap_le_send_data(le_data_channel_connection.cid, (uint8_t *) le_data_channel_connection.test_data, le_data_channel_connection.test_data_len);
// track
test_track_data(&le_data_channel_connection, le_data_channel_connection.test_data_len);
// request another packet
l2cap_le_request_can_send_now_event(le_data_channel_connection.cid);
}
/* LISTING_END */
#endif
/*
* @section HCI + L2CAP Packet Handler
*
* @text The packet handler is used to stop the notifications and reset the MTU on connect
* It would also be a good place to request the connection parameter update as indicated
* in the commented code block.
*/
/* LISTING_START(packetHandler): Packet Handler */
static void packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
UNUSED(channel);
bd_addr_t event_address;
uint16_t psm;
uint16_t cid;
uint16_t conn_interval;
hci_con_handle_t handle;
uint8_t status;
switch (packet_type) {
case HCI_EVENT_PACKET:
switch (hci_event_packet_get_type(packet)) {
case BTSTACK_EVENT_STATE:
// BTstack activated, get started
if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING) {
printf("To start the streaming, please run the le_data_channel_client example on other device.\n");
}
break;
case HCI_EVENT_DISCONNECTION_COMPLETE:
// free connection
printf("%c: Disconnect, reason %02x\n", le_data_channel_connection.name, hci_event_disconnection_complete_get_reason(packet));
le_data_channel_connection.connection_handle = HCI_CON_HANDLE_INVALID;
break;
case HCI_EVENT_LE_META:
switch (hci_event_le_meta_get_subevent_code(packet)) {
case HCI_SUBEVENT_LE_CONNECTION_COMPLETE:
// print connection parameters (without using float operations)
conn_interval = hci_subevent_le_connection_complete_get_conn_interval(packet);
printf("%c: Connection Interval: %u.%02u ms\n", le_data_channel_connection.name, conn_interval * 125 / 100, 25 * (conn_interval & 3));
printf("%c: Connection Latency: %u\n", le_data_channel_connection.name, hci_subevent_le_connection_complete_get_conn_latency(packet));
// min con interval 15 ms - supported from iOS 11
gap_request_connection_parameter_update(le_data_channel_connection.connection_handle, 12, 12, 0, 0x0048);
printf("Connected, requesting conn param update for handle 0x%04x\n", le_data_channel_connection.connection_handle);
//
test_reset(&le_data_channel_connection);
break;
case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE:
// print connection parameters (without using float operations)
conn_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
printf("LE Connection Update:\n");
printf("%c: Connection Interval: %u.%02u ms\n", le_data_channel_connection.name, conn_interval * 125 / 100, 25 * (conn_interval & 3));
printf("%c: Connection Latency: %u\n", le_data_channel_connection.name, hci_subevent_le_connection_update_complete_get_conn_latency(packet));
break;
default:
break;
}
break;
case L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_RESPONSE:
printf("L2CAP Connection Parameter Update Complete, response: %x\n", l2cap_event_connection_parameter_update_response_get_result(packet));
break;
// LE Data Channels
case L2CAP_EVENT_LE_INCOMING_CONNECTION:
psm = l2cap_event_le_incoming_connection_get_psm(packet);
cid = l2cap_event_le_incoming_connection_get_local_cid(packet);
if (psm != TSPX_le_psm) break;
printf("L2CAP: Accepting incoming LE connection request for 0x%02x, PSM %02x\n", cid, psm);
l2cap_le_accept_connection(cid, data_channel_buffer, sizeof(data_channel_buffer), initial_credits);
break;
case L2CAP_EVENT_LE_CHANNEL_OPENED:
// inform about new l2cap connection
l2cap_event_le_channel_opened_get_address(packet, event_address);
psm = l2cap_event_le_channel_opened_get_psm(packet);
cid = l2cap_event_le_channel_opened_get_local_cid(packet);
handle = l2cap_event_le_channel_opened_get_handle(packet);
status = l2cap_event_le_channel_opened_get_status(packet);
if (status == ERROR_CODE_SUCCESS) {
printf("L2CAP: LE Data Channel successfully opened: %s, handle 0x%02x, psm 0x%02x, local cid 0x%02x, remote cid 0x%02x\n",
bd_addr_to_str(event_address), handle, psm, cid, little_endian_read_16(packet, 15));
// setup new
le_data_channel_connection.counter = 'A';
le_data_channel_connection.cid = cid;
le_data_channel_connection.connection_handle = handle;
le_data_channel_connection.test_data_len = btstack_min(l2cap_event_le_channel_opened_get_remote_mtu(packet), sizeof(le_data_channel_connection.test_data));
printf("Test packet size: %u\n", le_data_channel_connection.test_data_len);
test_reset(&le_data_channel_connection);
#ifdef TEST_STREAM_DATA
l2cap_le_request_can_send_now_event(le_data_channel_connection.cid);
#endif
} else {
printf("L2CAP: LE Data Channel connection to device %s failed. status code %u\n", bd_addr_to_str(event_address), status);
}
break;
case L2CAP_EVENT_LE_CHANNEL_CLOSED:
printf("L2CAP: LE Data Channel closed\n");
le_data_channel_connection.cid = 0;
break;
#ifdef TEST_STREAM_DATA
case L2CAP_EVENT_LE_CAN_SEND_NOW:
streamer();
break;
#endif
default:
break;
}
break;
case L2CAP_DATA_PACKET:
test_track_data(&le_data_channel_connection, size);
break;
default:
break;
}
}
/*
* @section SM Packet Handler
*
* @text The packet handler is used to handle pairing requests
*/
static void sm_packet_handler (uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
UNUSED(channel);
UNUSED(size);
if (packet_type != HCI_EVENT_PACKET) return;
switch (hci_event_packet_get_type(packet)) {
case SM_EVENT_JUST_WORKS_REQUEST:
printf("Just Works requested\n");
sm_just_works_confirm(sm_event_just_works_request_get_handle(packet));
break;
case SM_EVENT_NUMERIC_COMPARISON_REQUEST:
printf("Confirming numeric comparison: %"PRIu32"\n", sm_event_numeric_comparison_request_get_passkey(packet));
sm_numeric_comparison_confirm(sm_event_passkey_display_number_get_handle(packet));
break;
case SM_EVENT_PASSKEY_DISPLAY_NUMBER:
printf("Display Passkey: %"PRIu32"\n", sm_event_passkey_display_number_get_passkey(packet));
break;
default:
break;
}
}
int btstack_main(void);
int btstack_main(void)
{
le_data_channel_setup();
// turn on!
hci_power_control(HCI_POWER_ON);
return 0;
}
/* EXAMPLE_END */