Diff: services/URIBeacon2Service.h

Revision:

169:e030a9308fcc

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/services/URIBeacon2Service.h	Fri Nov 28 14:11:22 2014 +0000
@@ -0,0 +1,248 @@
+/* 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.
+ */
+
+#ifndef __BLE_URI_BEACON_2_SERVICE_H__
+#define __BLE_URI_BEACON_2_SERVICE_H__
+
+#include "BLEDevice.h"
+
+#define UUID_INITIALIZER_LIST(FIRST, SECOND) {         \
+    0xee, 0x0c, FIRST, SECOND, 0x87, 0x86, 0x40, 0xba, \
+    0xab, 0x96, 0x99, 0xb9, 0x1a, 0xc9, 0x81, 0xd8,    \
+}
+const uint8_t URIBeacon2ControlServiceUUID[] = UUID_INITIALIZER_LIST(0x20, 0x80);
+const uint8_t lockedStateCharUUID[]          = UUID_INITIALIZER_LIST(0x20, 0x81);
+const uint8_t uriDataCharUUID[]              = UUID_INITIALIZER_LIST(0x20, 0x84);
+const uint8_t flagsCharUUID[]                = UUID_INITIALIZER_LIST(0x20, 0x85);
+const uint8_t txPowerCharUUID[]              = UUID_INITIALIZER_LIST(0x20, 0x86);
+const uint8_t beaconPeriodCharUUID[]         = UUID_INITIALIZER_LIST(0x20, 0x88);
+
+class URIBeacon2Service {
+public:
+    URIBeacon2Service(BLEDevice &ble_, const char *urldata, uint8_t flags_ = 0, uint8_t power_ = 0) :
+        ble(ble_), payloadIndex(0), serviceDataPayload(),
+        lockedState(false),
+        uriDataLength(0),
+        uriDataValue(),
+        flags(flags_),
+        power(power_),
+        beaconPeriod(Gap::MSEC_TO_ADVERTISEMENT_DURATION_UNITS(1000)), /* 1hz */
+        lockedStateChar(lockedStateCharUUID, (uint8_t *)&lockedState, 1, 1, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ),
+        uriDataChar(uriDataCharUUID,
+                    uriDataValue,
+                    MAX_SIZE_URI_DATA_CHAR_VALUE,
+                    MAX_SIZE_URI_DATA_CHAR_VALUE,
+                    GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE_WITHOUT_RESPONSE),
+        flagsChar(flagsCharUUID, &flags, 1, 1, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE),
+        // txPowerChar(txPowerCharUUID, &power, 1, 1, GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE)
+        beaconPeriodChar(beaconPeriodCharUUID, (uint8_t *)&beaconPeriod, 2, 2,
+                         GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_READ | GattCharacteristic::BLE_GATT_CHAR_PROPERTIES_WRITE)
+    {
+        if ((urldata == NULL) || ((uriDataLength = strlen(urldata)) == 0)) {
+            return;
+        }
+        strncpy(reinterpret_cast<char *>(uriDataValue), urldata, MAX_SIZE_URI_DATA_CHAR_VALUE);
+
+        setup();
+
+        static bool serviceAdded = false; /* We should only ever need to add the heart rate service once. */
+        if (serviceAdded) {
+            return;
+        }
+
+        GattCharacteristic *charTable[] = {&lockedStateChar, &uriDataChar, &flagsChar, &beaconPeriodChar};
+        GattService         beaconControlService(URIBeacon2ControlServiceUUID, charTable, sizeof(charTable) / sizeof(GattCharacteristic *));
+
+        ble.addService(beaconControlService);
+        serviceAdded = true;
+
+        ble.onDataWritten(this, &URIBeacon2Service::onDataWritten);
+    }
+
+protected:
+    /**
+     * This callback allows the DFU service to receive the initial trigger to
+     * handover control to the bootloader; but first the application is given a
+     * chance to clean up.
+     */
+    virtual void onDataWritten(const GattCharacteristicWriteCBParams *params) {
+        if (params->charHandle == uriDataChar.getValueAttribute().getHandle()) {
+            if (lockedState) { /* When locked, the device isn't allowed to update the uriData characteristic. */
+                /* Restore GATT database with previous value. */
+                ble.updateCharacteristicValue(uriDataChar.getValueAttribute().getHandle(), uriDataValue, uriDataLength);
+                return;
+            }
+
+            /* We don't handle very large writes at the moment. */
+            if ((params->offset != 0) || (params->len > MAX_SIZE_URI_DATA_CHAR_VALUE)) {
+                return;
+            }
+
+            uriDataLength = params->len;
+            memcpy(uriDataValue, params->data, uriDataLength);
+        } else if (params->charHandle == flagsChar.getValueAttribute().getHandle()) {
+            if (lockedState) { /* When locked, the device isn't allowed to update the flags characteristic. */
+                /* Restore GATT database with previous value. */
+                ble.updateCharacteristicValue(flagsChar.getValueAttribute().getHandle(), &flags, 1 /* size */);
+                return;
+            } else {
+                flags = *(params->data);
+            }
+        } else if (params->charHandle == beaconPeriodChar.getValueAttribute().getHandle()) {
+            if (lockedState) { /* When locked, the device isn't allowed to update the flags characteristic. */
+                /* Restore GATT database with previous value. */
+                ble.updateCharacteristicValue(beaconPeriodChar.getValueAttribute().getHandle(), (uint8_t *)&beaconPeriod, 2 /* size */);
+                return;
+            } else {
+                beaconPeriod = *((uint16_t *)(params->data));
+            }
+        }
+        setup();
+        ble.setAdvertisingPayload();
+    }
+
+    /**
+     * For debugging only.
+     */
+    void dumpEncodedSeviceData() const {
+        printf("encoded: '");
+        for (unsigned i = 0; i < payloadIndex; i++) {
+            printf(" %02x", serviceDataPayload[i]);
+        }
+        printf("'\r\n");
+    }
+
+private:
+    void setup(void) {
+        const uint8_t BEACON_UUID[] = {0xD8, 0xFE};
+
+        payloadIndex = 0;
+        serviceDataPayload[payloadIndex++] = BEACON_UUID[0];
+        serviceDataPayload[payloadIndex++] = BEACON_UUID[1];
+        serviceDataPayload[payloadIndex++] = flags;
+        serviceDataPayload[payloadIndex++] = power;
+
+        const char *urlData = reinterpret_cast<char *>(uriDataValue);
+        size_t sizeofURLData = uriDataLength;
+        size_t encodedBytes = encodeURISchemePrefix(urlData, sizeofURLData) + encodeURI(urlData, sizeofURLData);
+
+        ble.clearAdvertisingPayload();
+        ble.accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_16BIT_SERVICE_IDS, BEACON_UUID, sizeof(BEACON_UUID));
+        ble.accumulateAdvertisingPayload(GapAdvertisingData::SERVICE_DATA, serviceDataPayload, encodedBytes + 4);
+
+        ble.setAdvertisingInterval(beaconPeriod);
+        ble.setTxPower(power);
+    }
+
+    size_t encodeURISchemePrefix(const char *&urldata, size_t &sizeofURLData) {
+        const char *prefixes[] = {
+            "http://www.",
+            "https://www.",
+            "http://",
+            "https://",
+            "urn:uuid:"
+        };
+
+        size_t encodedBytes = 0;
+        const size_t NUM_PREFIXES = sizeof(prefixes) / sizeof(char *);
+        for (unsigned i = 0; i < NUM_PREFIXES; i++) {
+            size_t prefixLen = strlen(prefixes[i]);
+            if (strncmp(urldata, prefixes[i], prefixLen) == 0) {
+                serviceDataPayload[payloadIndex++] = i;
+                encodedBytes = 1;
+
+                urldata      += prefixLen;
+                sizeofURLData -= prefixLen;
+                break;
+            }
+        }
+
+        return encodedBytes;
+    }
+
+    size_t encodeURI(const char *urldata, size_t sizeofURLData) {
+        const char *suffixes[] = {
+            ".com/",
+            ".org/",
+            ".edu/",
+            ".net/",
+            ".info/",
+            ".biz/",
+            ".gov/",
+            ".com",
+            ".org",
+            ".edu",
+            ".net",
+            ".info",
+            ".biz",
+            ".gov"
+        };
+        const size_t NUM_SUFFIXES = sizeof(suffixes) / sizeof(char *);
+
+        size_t encodedBytes = 0;
+        while (sizeofURLData && (payloadIndex < MAX_SIZEOF_SERVICE_DATA_PAYLOAD)) {
+            /* check for suffix match */
+            unsigned i;
+            for (i = 0; i < NUM_SUFFIXES; i++) {
+                size_t suffixLen = strlen(suffixes[i]);
+                if ((suffixLen == 0) || (sizeofURLData < suffixLen)) {
+                    continue;
+                }
+
+                if (strncmp(urldata, suffixes[i], suffixLen) == 0) {
+                    serviceDataPayload[payloadIndex++] = i;
+                    ++encodedBytes;
+                    urldata       += suffixLen;
+                    sizeofURLData -= suffixLen;
+                    break; /* from the for loop for checking against suffixes */
+                }
+            }
+            /* This is the default case where we've got an ordinary character which doesn't match a suffix. */
+            if (i == NUM_SUFFIXES) {
+                serviceDataPayload[payloadIndex++] = *urldata;
+                ++encodedBytes;
+                ++urldata;
+                --sizeofURLData;
+            }
+        }
+
+        return encodedBytes;
+    }
+
+private:
+    static const size_t MAX_SIZEOF_SERVICE_DATA_PAYLOAD = 27;
+    static const size_t MAX_SIZE_URI_DATA_CHAR_VALUE    = 48;
+
+private:
+    BLEDevice &ble;
+
+    size_t   payloadIndex;
+    uint8_t  serviceDataPayload[MAX_SIZEOF_SERVICE_DATA_PAYLOAD];
+    bool     lockedState;
+    uint16_t uriDataLength;
+    uint8_t  uriDataValue[MAX_SIZE_URI_DATA_CHAR_VALUE];
+    uint8_t  flags;
+    uint8_t  power;
+    uint16_t beaconPeriod;
+
+    GattCharacteristic lockedStateChar;
+    GattCharacteristic uriDataChar;
+    GattCharacteristic flagsChar;
+    // GattCharacteristic txPowerChar;
+    GattCharacteristic beaconPeriodChar;
+};
+
+#endif /* #ifndef __BLE_URI_BEACON_2_SERVICE_H__*/
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