Implement direct_bt: Direct Bluetooth access via Linux's Kernel BlueZ protocol stack w/o D-Bus bluetoothd.

By dropping BlueZ userspace D-Bus bluetoothd, we target high-performance reliable bluetooth support
with least dependencies for embedded device configurations.

See COPYING, describing which Linux Kernel BlueZ IOCTL information has been included in the source tree.
We claim Linus Torvalds's Linux Kernel license exception regarding kernel syscalls (ioctl):
<https://github.com/torvalds/linux/blob/master/LICENSES/exceptions/Linux-syscall-note>
and hence maintain this project's license.

The new direct_bt feature set is organized as follows
- include/cppunit
- api/direct_bt
- api/ieee11073
- src/direct_bt
- examples/direct_bt

Note that the C++ direct_bt layer is not backward compatible to tinyb.

Since the Java layer still needs to be completed,
it has to be seen whether we will achieve compatibility
or drop the original D-Bus tinyb module altogether
in favor of a more streamlined API and implementation.

Current state allows scanning for LE devices, connecting
and parsing GATT plus receiving notifications and indications.
See examples/direct_bt_scanner/dbt_scanner.cpp.

The Linux Kernel BlueZ is configured via module MgmtComm.[hpp/cpp]

1 files changed, 214 insertions, 0 deletions

diff --git a/examples/tinyb/hellotinyb.cpp b/examples/tinyb/hellotinyb.cpp
new file mode 100644
index 00000000..49886195
--- /dev/null
+++ b/examples/tinyb/hellotinyb.cpp
@@ -0,0 +1,214 @@
+/*
+ * Author: Petre Eftime <[email protected]>
+ * Copyright (c) 2015 Intel Corporation.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+#include <tinyb.hpp>
+
+#include <vector>
+#include <iostream>
+#include <thread>
+#include <atomic>
+#include <csignal>
+
+using namespace tinyb;
+
+/** Converts a raw temperature read from the sensor to a Celsius value.
+ * @param[in] raw_temp The temperature read from the sensor (two bytes)
+ * @return The Celsius value of the temperature
+ */
+static float celsius_temp(uint16_t raw_temp)
+{
+    const float SCALE_LSB = 0.03125;
+    return ((float)(raw_temp >> 2)) * SCALE_LSB;
+}
+
+
+std::atomic<bool> running(true);
+
+void signal_handler(int signum)
+{
+    if (signum == SIGINT) {
+        running = false;
+    }
+}
+
+/** This program reads the temperature from a
+ * TI Sensor Tag(http://www.ti.com/ww/en/wireless_connectivity/sensortag2015/?INTC=SensorTag&HQS=sensortag)
+ * Pass the MAC address of the sensor as the first parameter of the program.
+ */
+int main(int argc, char **argv)
+{
+    if (argc < 2) {
+        std::cerr << "Run as: " << argv[0] << " <device_address>" << std::endl;
+        exit(1);
+    }
+
+   BluetoothManager *manager = nullptr;
+    try {
+        manager = BluetoothManager::get_bluetooth_manager();
+    } catch(const std::runtime_error& e) {
+        std::cerr << "Error while initializing libtinyb: " << e.what() << std::endl;
+        exit(1);
+    }
+
+    /* Start the discovery of devices */
+    bool ret = manager->start_discovery();
+    std::cout << "Started = " << (ret ? "true" : "false") << std::endl;
+
+    BluetoothDevice *sensor_tag = NULL;
+    BluetoothGattService *temperature_service = NULL;
+
+    for (int i = 0; i < 15; ++i) {
+        std::cout << "Discovered devices: " << std::endl;
+        /* Get the list of devices */
+        auto list = manager->get_devices();
+
+        for (auto it = list.begin(); it != list.end(); ++it) {
+
+            std::cout << "Class = " << (*it)->get_class_name() << " ";
+            std::cout << "Path = " << (*it)->get_object_path() << " ";
+            std::cout << "Name = " << (*it)->get_name() << " ";
+            std::cout << "Connected = " << (*it)->get_connected() << " ";
+            std::cout << std::endl;
+
+            /* Search for the device with the address given as a parameter to the program */
+            if ((*it)->get_address() == argv[1])
+                sensor_tag = (*it).release();
+        }
+
+        /* Free the list of devices and stop if the device was found */
+        if (sensor_tag != nullptr)
+            break;
+        /* If not, wait and try again */
+        std::this_thread::sleep_for(std::chrono::seconds(4));
+        std::cout << std::endl;
+    }
+
+    /* Stop the discovery (the device was found or number of tries ran out */
+    ret = manager->stop_discovery();
+    std::cout << "Stopped = " << (ret ? "true" : "false") << std::endl;
+
+    if (sensor_tag == nullptr) {
+        std::cout << "Could not find device " << argv[1] << std::endl;
+        return 1;
+    }
+
+    /* Connect to the device and get the list of services exposed by it */
+    sensor_tag->connect();
+    std::cout << "Discovered services: " << std::endl;
+    while (true) {
+        /* Wait for the device to come online */
+        std::this_thread::sleep_for(std::chrono::seconds(4));
+
+        auto list = sensor_tag->get_services();
+        if (list.empty())
+            continue;
+
+        for (auto it = list.begin(); it != list.end(); ++it) {
+            std::cout << "Class = " << (*it)->get_class_name() << " ";
+            std::cout << "Path = " << (*it)->get_object_path() << " ";
+            std::cout << "UUID = " << (*it)->get_uuid() << " ";
+            std::cout << "Device = " << (*it)->get_device().get_object_path() << " ";
+            std::cout << std::endl;
+
+            /* Search for the temperature service, by UUID */
+            if ((*it)->get_uuid() == "f000aa00-0451-4000-b000-000000000000")
+                temperature_service = (*it).release();
+        }
+        break;
+    }
+
+    if (temperature_service == nullptr) {
+        std::cout << "Could not find service f000aa00-0451-4000-b000-000000000000" << std::endl;
+        return 1;
+    }
+
+    BluetoothGattCharacteristic *temp_value = nullptr;
+    BluetoothGattCharacteristic *temp_config = nullptr;
+    BluetoothGattCharacteristic *temp_period = nullptr;
+
+    /* If there is a temperature service on the device with the given UUID,
+     * get it's characteristics, by UUID again */
+    auto list = temperature_service->get_characteristics();
+    std::cout << "Discovered characteristics: " << std::endl;
+    for (auto it = list.begin(); it != list.end(); ++it) {
+
+        std::cout << "Class = " << (*it)->get_class_name() << " ";
+        std::cout << "Path = " << (*it)->get_object_path() << " ";
+        std::cout << "UUID = " << (*it)->get_uuid() << " ";
+        std::cout << "Service = " << (*it)->get_service().get_object_path() << " ";
+        std::cout << std::endl;
+
+        if ((*it)->get_uuid() == "f000aa01-0451-4000-b000-000000000000")
+            temp_value = (*it).release();
+        else if ((*it)->get_uuid() =="f000aa02-0451-4000-b000-000000000000")
+            temp_config = (*it).release();
+        else if ((*it)->get_uuid() == "f000aa03-0451-4000-b000-000000000000")
+            temp_period = (*it).release();
+    }
+
+    if (temp_config == nullptr || temp_value == nullptr || temp_period == nullptr) {
+        std::cout << "Could not find characteristics." << std::endl;
+        return 1;
+    }
+
+    /* Activate the temperature measurements */
+    try {
+        std::vector<unsigned char> config_on {0x01};
+        temp_config->write_value(config_on);
+        while (running) {
+            /* Read temperature data and display it */
+            std::vector<unsigned char> response = temp_value->read_value();
+            unsigned char *data;
+            unsigned int size = response.size();
+            if (size > 0) {
+                data = response.data();
+
+                std::cout << "Raw data=[";
+                for (unsigned i = 0; i < response.size(); i++)
+                    std::cout << std::hex << static_cast<int>(data[i]) << ", ";
+                std::cout << "] ";
+
+                uint16_t ambient_temp, object_temp;
+                object_temp = data[0] | (data[1] << 8);
+                ambient_temp = data[2] | (data[3] << 8);
+
+                std::cout << "Ambient temp: " << celsius_temp(ambient_temp) << "C ";
+                std::cout << "Object temp: " << celsius_temp(object_temp) << "C ";
+                std::cout << std::endl;
+            }
+
+            std::this_thread::sleep_for(std::chrono::seconds(1));
+        }
+    } catch (std::exception &e) {
+        std::cout << "Error: " << e.what() << std::endl;
+    }
+
+    /* Disconnect from the device */
+     try {
+        sensor_tag->disconnect();
+    } catch (std::exception &e) {
+        std::cout << "Error: " << e.what() << std::endl;
+    }
+    return 0;
+}