Diff: main.cpp

Revision:

0:c671a4833315

Child:

21:51e162c130a9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp	Wed Jun 20 11:03:22 2018 +0100
@@ -0,0 +1,411 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2017 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 <stdio.h>
+
+#include "platform/Callback.h"
+#include "events/EventQueue.h"
+#include "platform/NonCopyable.h"
+
+#include "ble/BLE.h"
+#include "ble/Gap.h"
+#include "ble/GattClient.h"
+#include "ble/GapAdvertisingParams.h"
+#include "ble/GapAdvertisingData.h"
+#include "ble/GattServer.h"
+#include "BLEProcess.h"
+
+using mbed::callback;
+
+/**
+ * A Clock service that demonstrate the GattServer features.
+ *
+ * The clock service host three characteristics that model the current hour,
+ * minute and second of the clock. The value of the second characteristic is
+ * incremented automatically by the system.
+ *
+ * A client can subscribe to updates of the clock characteristics and get
+ * notified when one of the value is changed. Clients can also change value of
+ * the second, minute and hour characteristric.
+ */
+class ClockService {
+    typedef ClockService Self;
+
+public:
+    ClockService() :
+        _hour_char("485f4145-52b9-4644-af1f-7a6b9322490f", 0),
+        _minute_char("0a924ca7-87cd-4699-a3bd-abdcd9cf126a", 0),
+        _second_char("8dd6a1b7-bc75-4741-8a26-264af75807de", 0),
+        _clock_service(
+            /* uuid */ "51311102-030e-485f-b122-f8f381aa84ed",
+            /* characteristics */ _clock_characteristics,
+            /* numCharacteristics */ sizeof(_clock_characteristics) /
+                                     sizeof(_clock_characteristics[0])
+        ),
+        _server(NULL),
+        _event_queue(NULL)
+    {
+        // update internal pointers (value, descriptors and characteristics array)
+        _clock_characteristics[0] = &_hour_char;
+        _clock_characteristics[1] = &_minute_char;
+        _clock_characteristics[2] = &_second_char;
+
+        // setup authorization handlers
+        _hour_char.setWriteAuthorizationCallback(this, &Self::authorize_client_write);
+        _minute_char.setWriteAuthorizationCallback(this, &Self::authorize_client_write);
+        _second_char.setWriteAuthorizationCallback(this, &Self::authorize_client_write);
+    }
+
+
+
+    void start(BLE &ble_interface, events::EventQueue &event_queue)
+    {
+         if (_event_queue) {
+            return;
+        }
+
+        _server = &ble_interface.gattServer();
+        _event_queue = &event_queue;
+
+        // register the service
+        printf("Adding demo service\r\n");
+        ble_error_t err = _server->addService(_clock_service);
+
+        if (err) {
+            printf("Error %u during demo service registration.\r\n", err);
+            return;
+        }
+
+        // read write handler
+        _server->onDataSent(as_cb(&Self::when_data_sent));
+        _server->onDataWritten(as_cb(&Self::when_data_written));
+        _server->onDataRead(as_cb(&Self::when_data_read));
+
+        // updates subscribtion handlers
+        _server->onUpdatesEnabled(as_cb(&Self::when_update_enabled));
+        _server->onUpdatesDisabled(as_cb(&Self::when_update_disabled));
+        _server->onConfirmationReceived(as_cb(&Self::when_confirmation_received));
+
+        // print the handles
+        printf("clock service registered\r\n");
+        printf("service handle: %u\r\n", _clock_service.getHandle());
+        printf("\thour characteristic value handle %u\r\n", _hour_char.getValueHandle());
+        printf("\tminute characteristic value handle %u\r\n", _minute_char.getValueHandle());
+        printf("\tsecond characteristic value handle %u\r\n", _second_char.getValueHandle());
+
+        _event_queue->call_every(1000 /* ms */, callback(this, &Self::increment_second));
+    }
+
+private:
+
+    /**
+     * Handler called when a notification or an indication has been sent.
+     */
+    void when_data_sent(unsigned count)
+    {
+        printf("sent %u updates\r\n", count);
+    }
+
+    /**
+     * Handler called after an attribute has been written.
+     */
+    void when_data_written(const GattWriteCallbackParams *e)
+    {
+        printf("data written:\r\n");
+        printf("\tconnection handle: %u\r\n", e->connHandle);
+        printf("\tattribute handle: %u", e->handle);
+        if (e->handle == _hour_char.getValueHandle()) {
+            printf(" (hour characteristic)\r\n");
+        } else if (e->handle == _minute_char.getValueHandle()) {
+            printf(" (minute characteristic)\r\n");
+        } else if (e->handle == _second_char.getValueHandle()) {
+            printf(" (second characteristic)\r\n");
+        } else {
+            printf("\r\n");
+        }
+        printf("\twrite operation: %u\r\n", e->writeOp);
+        printf("\toffset: %u\r\n", e->offset);
+        printf("\tlength: %u\r\n", e->len);
+        printf("\t data: ");
+
+        for (size_t i = 0; i < e->len; ++i) {
+            printf("%02X", e->data[i]);
+        }
+
+        printf("\r\n");
+    }
+
+    /**
+     * Handler called after an attribute has been read.
+     */
+    void when_data_read(const GattReadCallbackParams *e)
+    {
+        printf("data read:\r\n");
+        printf("\tconnection handle: %u\r\n", e->connHandle);
+        printf("\tattribute handle: %u", e->handle);
+        if (e->handle == _hour_char.getValueHandle()) {
+            printf(" (hour characteristic)\r\n");
+        } else if (e->handle == _minute_char.getValueHandle()) {
+            printf(" (minute characteristic)\r\n");
+        } else if (e->handle == _second_char.getValueHandle()) {
+            printf(" (second characteristic)\r\n");
+        } else {
+            printf("\r\n");
+        }
+    }
+
+    /**
+     * Handler called after a client has subscribed to notification or indication.
+     *
+     * @param handle Handle of the characteristic value affected by the change.
+     */
+    void when_update_enabled(GattAttribute::Handle_t handle)
+    {
+        printf("update enabled on handle %d\r\n", handle);
+    }
+
+    /**
+     * Handler called after a client has cancelled his subscription from
+     * notification or indication.
+     *
+     * @param handle Handle of the characteristic value affected by the change.
+     */
+    void when_update_disabled(GattAttribute::Handle_t handle)
+    {
+        printf("update disabled on handle %d\r\n", handle);
+    }
+
+    /**
+     * Handler called when an indication confirmation has been received.
+     *
+     * @param handle Handle of the characteristic value that has emitted the
+     * indication.
+     */
+    void when_confirmation_received(GattAttribute::Handle_t handle)
+    {
+        printf("confirmation received on handle %d\r\n", handle);
+    }
+
+    /**
+     * Handler called when a write request is received.
+     *
+     * This handler verify that the value submitted by the client is valid before
+     * authorizing the operation.
+     */
+    void authorize_client_write(GattWriteAuthCallbackParams *e)
+    {
+        printf("characteristic %u write authorization\r\n", e->handle);
+
+        if (e->offset != 0) {
+            printf("Error invalid offset\r\n");
+            e->authorizationReply = AUTH_CALLBACK_REPLY_ATTERR_INVALID_OFFSET;
+            return;
+        }
+
+        if (e->len != 1) {
+            printf("Error invalid len\r\n");
+            e->authorizationReply = AUTH_CALLBACK_REPLY_ATTERR_INVALID_ATT_VAL_LENGTH;
+            return;
+        }
+
+        if ((e->data[0] >= 60) ||
+            ((e->data[0] >= 24) && (e->handle == _hour_char.getValueHandle()))) {
+            printf("Error invalid data\r\n");
+            e->authorizationReply = AUTH_CALLBACK_REPLY_ATTERR_WRITE_NOT_PERMITTED;
+            return;
+        }
+
+        e->authorizationReply = AUTH_CALLBACK_REPLY_SUCCESS;
+    }
+
+    /**
+     * Increment the second counter.
+     */
+    void increment_second(void)
+    {
+        uint8_t second = 0;
+        ble_error_t err = _second_char.get(*_server, second);
+        if (err) {
+            printf("read of the second value returned error %u\r\n", err);
+            return;
+        }
+
+        second = (second + 1) % 60;
+
+        err = _second_char.set(*_server, second);
+        if (err) {
+            printf("write of the second value returned error %u\r\n", err);
+            return;
+        }
+
+        if (second == 0) {
+            increment_minute();
+        }
+    }
+
+    /**
+     * Increment the minute counter.
+     */
+    void increment_minute(void)
+    {
+        uint8_t minute = 0;
+        ble_error_t err = _minute_char.get(*_server, minute);
+        if (err) {
+            printf("read of the minute value returned error %u\r\n", err);
+            return;
+        }
+
+        minute = (minute + 1) % 60;
+
+        err = _minute_char.set(*_server, minute);
+        if (err) {
+            printf("write of the minute value returned error %u\r\n", err);
+            return;
+        }
+
+        if (minute == 0) {
+            increment_hour();
+        }
+    }
+
+    /**
+     * Increment the hour counter.
+     */
+    void increment_hour(void)
+    {
+        uint8_t hour = 0;
+        ble_error_t err = _hour_char.get(*_server, hour);
+        if (err) {
+            printf("read of the hour value returned error %u\r\n", err);
+            return;
+        }
+
+        hour = (hour + 1) % 24;
+
+        err = _hour_char.set(*_server, hour);
+        if (err) {
+            printf("write of the hour value returned error %u\r\n", err);
+            return;
+        }
+    }
+
+private:
+    /**
+     * Helper that construct an event handler from a member function of this
+     * instance.
+     */
+    template<typename Arg>
+    FunctionPointerWithContext<Arg> as_cb(void (Self::*member)(Arg))
+    {
+        return makeFunctionPointer(this, member);
+    }
+
+    /**
+     * Read, Write, Notify, Indicate  Characteristic declaration helper.
+     *
+     * @tparam T type of data held by the characteristic.
+     */
+    template<typename T>
+    class ReadWriteNotifyIndicateCharacteristic : public GattCharacteristic {
+    public:
+        /**
+         * Construct a characteristic that can be read or written and emit
+         * notification or indication.
+         *
+         * @param[in] uuid The UUID of the characteristic.
+         * @param[in] initial_value Initial value contained by the characteristic.
+         */
+        ReadWriteNotifyIndicateCharacteristic(const UUID & uuid, const T& initial_value) :
+            GattCharacteristic(
+                /* UUID */ uuid,
+                /* Initial value */ &_value,
+                /* Value size */ sizeof(_value),
+                /* Value capacity */ sizeof(_value),
+                /* Properties */ GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ |
+                                GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE |
+                                GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_NOTIFY |
+                                GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_INDICATE,
+                /* Descriptors */ NULL,
+                /* Num descriptors */ 0,
+                /* variable len */ false
+            ),
+            _value(initial_value) {
+        }
+
+        /**
+         * Get the value of this characteristic.
+         *
+         * @param[in] server GattServer instance that contain the characteristic
+         * value.
+         * @param[in] dst Variable that will receive the characteristic value.
+         *
+         * @return BLE_ERROR_NONE in case of success or an appropriate error code.
+         */
+        ble_error_t get(GattServer &server, T& dst) const
+        {
+            uint16_t value_length = sizeof(dst);
+            return server.read(getValueHandle(), &dst, &value_length);
+        }
+
+        /**
+         * Assign a new value to this characteristic.
+         *
+         * @param[in] server GattServer instance that will receive the new value.
+         * @param[in] value The new value to set.
+         * @param[in] local_only Flag that determine if the change should be kept
+         * locally or forwarded to subscribed clients.
+         */
+        ble_error_t set(
+            GattServer &server, const uint8_t &value, bool local_only = false
+        ) const {
+            return server.write(getValueHandle(), &value, sizeof(value), local_only);
+        }
+
+    private:
+        uint8_t _value;
+    };
+
+    ReadWriteNotifyIndicateCharacteristic<uint8_t> _hour_char;
+    ReadWriteNotifyIndicateCharacteristic<uint8_t> _minute_char;
+    ReadWriteNotifyIndicateCharacteristic<uint8_t> _second_char;
+
+    // list of the characteristics of the clock service
+    GattCharacteristic* _clock_characteristics[3];
+
+    // demo service
+    GattService _clock_service;
+
+    GattServer* _server;
+    events::EventQueue *_event_queue;
+};
+
+int main() {
+    BLE &ble_interface = BLE::Instance();
+    events::EventQueue event_queue;
+    ClockService demo_service;
+    BLEProcess ble_process(event_queue, ble_interface);
+
+    ble_process.on_init(callback(&demo_service, &ClockService::start));
+
+    // bind the event queue to the ble interface, initialize the interface
+    // and start advertising
+    ble_process.start();
+
+    // Process the event queue.
+    event_queue.dispatch_forever();
+
+    return 0;
+}