Mbed OS Reference | EddystoneService.h Source File

 /* mbed Microcontroller Library
  * Copyright (c) 2006-2015 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 SERVICES_EDDYSTONEBEACON_H_
 #define SERVICES_EDDYSTONEBEACON_H_
 
 #warning ble/services/EddystoneService.h is deprecated. Please use the example in 'github.com/ARMmbed/ble-examples/tree/master/BLE_EddystoneService'.
 
 #include "ble/BLE.h"
 #include "CircularBuffer.h"
 #include "Timer.h"
 #include "Ticker.h"
 #include "Timeout.h"
 
 #if BLE_FEATURE_GATT_SERVER
 
 static const uint8_t BEACON_EDDYSTONE[] = {0xAA, 0xFE};
 
 //Debug is disabled by default
 #if 0
 #define DBG(MSG, ...)  printf("[EddyStone: DBG]" MSG " \t[%s,%d]\r\n", \
                             ## __VA_ARGS__,                            \
                             __FILE__,                                  \
                             __LINE__);
 #define WARN(MSG, ...) printf("[EddyStone: WARN]" MSG " \t[%s,%d]\r\n", \
                             ## __VA_ARGS__,                             \
                             __FILE__,                                   \
                             __LINE__);
 #define ERR(MSG, ...)  printf("[EddyStone: ERR]" MSG " \t[%s,%d]\r\n", \
                             ## __VA_ARGS__,                            \
                             __FILE__,                                  \
                             __LINE__);
 #else // if 0
 #define DBG(x, ...) //wait_us(10);
 #define WARN(x, ...) //wait_us(10);
 #define ERR(x, ...)
 #endif // if 0
 
 #if 0
 #define INFO(x, ...)  printf("[EddyStone: INFO]"x " \t[%s,%d]\r\n", \
                              ## __VA_ARGS__,                        \
                              __FILE__,                              \
                              __LINE__);
 #else // if 0
 #define INFO(x, ...)
 #endif // if 0
 
 /**
 * @class Eddystone
 * @brief Eddystone Configuration Service. Can be used to set URL, adjust power levels, and set flags.
 * See https://github.com/google/eddystone
 *
 */
 class EddystoneService
 {
 public:
     enum FrameTypes {
         NONE,
         url,
         uid,
         tlm
     };
 
     static const int SERVICE_DATA_MAX = 31;             // Maximum size of service data in ADV packets
 
     // There are currently 3 subframes defined, URI, UID, and TLM
 #define EDDYSTONE_MAX_FRAMETYPE 3
     void (*frames[EDDYSTONE_MAX_FRAMETYPE])(uint8_t *, uint32_t);
     static const int URI_DATA_MAX = 18;
     typedef uint8_t  UriData_t[URI_DATA_MAX];
     mbed::CircularBuffer<FrameTypes, EDDYSTONE_MAX_FRAMETYPE> overflow;
 
     // UID Frame Type subfields
     static const int UID_NAMESPACEID_SIZE = 10;
     typedef uint8_t  UIDNamespaceID_t[UID_NAMESPACEID_SIZE];
     static const int UID_INSTANCEID_SIZE = 6;
     typedef uint8_t  UIDInstanceID_t[UID_INSTANCEID_SIZE];
 
     // Eddystone Frame Type ID
     static const uint8_t FRAME_TYPE_UID = 0x00;
     static const uint8_t FRAME_TYPE_URL = 0x10;
     static const uint8_t FRAME_TYPE_TLM = 0x20;
 
     static const uint8_t FRAME_SIZE_TLM = 14; // TLM frame is a constant 14Bytes
     static const uint8_t FRAME_SIZE_UID = 20; // includes RFU bytes
 
     /**
      *  Set Eddystone UID Frame information.
      *
      *  @param[in] power       TX Power in dB measured at 0 meters from the device. Range of -100 to +20 dB.
      *  @param[in] namespaceID 10B namespace ID
      *  @param[in] instanceID  6B instance ID
      *  @param[in] uidAdvPeriodIn Advertising period of UID frames.
      *  @param[in] RFU         2B of RFU, initialized to 0x0000 and not broadcast, included for future reference.
      */
     void setUIDFrameData(int8_t           power,
                          UIDNamespaceID_t namespaceID,
                          UIDInstanceID_t  instanceID,
                          float            uidAdvPeriodIn,
                          uint16_t         RFU = 0x0000) {
         if (0.0f == uidAdvPeriodIn) {
             uidIsSet = false;
             return;
         }
         if (power > 20) {
             power = 20;
         }
         if (power < -100) {
             power = -100;
         }
 
         defaultUidPower = power;
         memcpy(defaultUidNamespaceID, namespaceID, UID_NAMESPACEID_SIZE);
         memcpy(defaultUidInstanceID,  instanceID,  UID_INSTANCEID_SIZE);
         uidRFU       = (uint16_t)RFU; // this is probably bad form, but it doesn't really matter yet.
         uidAdvPeriod = uidAdvPeriodIn;
         uidIsSet     = true;          // set toggle to advertise UID frames
     }
 
     /*
     *  Construct UID frame from private variables
     *  @param[in/out] Data pointer to array to store constructed frame in
     *  @param[in] maxSize number of bytes left in array, effectively how much empty space is available to write to
     *  @return number of bytes used. negative number indicates error message.
     */
     unsigned constructUIDFrame(uint8_t *Data, uint8_t maxSize) {
         unsigned index = 0;
 
         Data[index++] = FRAME_TYPE_UID;                     // 1B  Type
 
         if (defaultUidPower > 20) {
             defaultUidPower = 20;                           // enforce range of vaild values.
         }
         if (defaultUidPower < -100) {
             defaultUidPower = -100;
         }
         Data[index++] = defaultUidPower;                    // 1B  Power @ 0meter
 
         DBG("UID NamespaceID = '0x");
         for (size_t x = 0; x < UID_NAMESPACEID_SIZE; x++) { // 10B Namespace ID
             Data[index++] = defaultUidNamespaceID[x];
             DBG("%x,", defaultUidNamespaceID[x]);
         }
         DBG("'\r\n");
 
         DBG("UID InstanceID = '0x");
         for (size_t x = 0; x< UID_INSTANCEID_SIZE; x++) {   // 6B  Instance ID
             Data[index++] = defaultUidInstanceID[x];
             DBG("%x,", defaultUidInstanceID[x]);
         }
         DBG("'\r\n");
 
         if (0 != uidRFU) {                                  // 2B RFU, include if non-zero, otherwise ignore
             Data[index++] = (uint8_t)(uidRFU >> 0);
             Data[index++] = (uint8_t)(uidRFU >> 8);
         }
         DBG("construcUIDFrame %d, %d", maxSize, index);
         return index;
     }
 
     /**
      *  Set Eddystone URL Frame information.
      *  @param[in] power          TX Power in dB measured at 0 meters from the device.
      *  @param[in] urlIn            URL to encode
      *  @param[in] urlAdvPeriodIn How long to advertise the URL frame (measured in # of adv periods)
      *  @return false on success, true on failure.
      */
     bool setURLFrameData(int8_t power, const char *urlIn, float urlAdvPeriodIn) {
         if (0.0f == urlAdvPeriodIn) {
             urlIsSet = false;
             return false;
         }
         encodeURL(urlIn, defaultUriData, defaultUriDataLength); // encode URL to URL Formatting
         if (defaultUriDataLength > URI_DATA_MAX) {
             return true;                                        // error, URL is too big
         }
         defaultUrlPower = power;
         urlAdvPeriod = urlAdvPeriodIn;
         urlIsSet     = true;
         return false;
     }
 
     /**
      *  Set Eddystone URL Frame information.
      *  @param[in] power              TX Power in dB measured at 0 meters from the device.
      *  @param[in] encodedUrlIn       Encoded URL
      *  @param[in] encodedUrlInLength Length of the encoded URL
      *  @param[in] urlAdvPeriodIn     How long to advertise the URL frame (measured in # of adv periods)
      *  @return false on success, true on failure.
      */
     bool setURLFrameEncodedData(int8_t power, const char *encodedUrlIn, uint8_t encodedUrlInLength, float urlAdvPeriodIn) {
         if (0.0f == urlAdvPeriodIn) {
             urlIsSet = false;
             return false;
         }
         memcpy(defaultUriData, encodedUrlIn, encodedUrlInLength);
         if (defaultUriDataLength > URI_DATA_MAX) {
             return true;                                        // error, URL is too big
         }
         defaultUrlPower      = power;
         defaultUriDataLength = encodedUrlInLength;
         urlAdvPeriod         = urlAdvPeriodIn;
         urlIsSet             = true;
         return false;
     }
 
     /*
     *  Construct URL frame from private variables
     *  @param[in/out] Data pointer to array to store constructed frame in
     *  @param[in] maxSize number of bytes left in array, effectively how much emtpy space is available to write to
     *  @return number of bytes used. negative number indicates error message.
     */
     int constructURLFrame(uint8_t *Data, uint8_t maxSize) {
         int index = 0;
         Data[index++] = FRAME_TYPE_URL;                     // 1B  Type
         Data[index++] = defaultUrlPower;                    // 1B  TX Power
         for (int x = 0; x < defaultUriDataLength; x++) {    // 18B of URL Prefix + encoded URL
             Data[index++] = defaultUriData[x];
         }
         DBG("constructURLFrame: %d, %d", maxSize, index);
         return index;
     }
 
     /*
     *  Set Eddystone TLM Frame information.
     *  @param[in] Version    of the TLM beacon data format
     *  @param[in] advPeriod  how often to advertise the TLM frame for (in minutes)
     *  @param batteryVoltage in milivolts
     *  @param beaconTemp     in 8.8 floating point notation
     *
     */
     void setTLMFrameData(uint8_t  version        = 0,
                          float    advPeriod      = 60.0f,
                          uint16_t batteryVoltage = 0,
                          uint16_t beaconTemp     = 0x8000,
                          uint32_t pduCount       = 0,
                          uint32_t timeSinceBoot  = 0) {
         if (0.0f == advPeriod) {
             tlmIsSet = false;
             return;
         }
         TlmVersion        = version;
         TlmBatteryVoltage = batteryVoltage;
         TlmBeaconTemp     = beaconTemp;
         TlmPduCount       = pduCount;      // reset
         TlmTimeSinceBoot  = timeSinceBoot; // reset
         TlmAdvPeriod      = advPeriod;
         tlmIsSet          = true;          // TLM Data has been enabled
     }
 
     /*
     *  Construct TLM frame from private variables
     *  @param[in/out] Data pointer to array to store constructed frame in
     *  @param[in] maxSize number of bytes left in array, effectively how much emtpy space is available to write to
     *  @return number of bytes used. negative number indicates error message.
     */
     int constructTLMFrame(uint8_t *Data, uint8_t maxSize) {
         uint32_t now = timeSinceBootTimer.read_ms();
         TlmTimeSinceBoot += (now - lastBootTimerRead) / 100;
         lastBootTimerRead = now;
 
         int index = 0;
         Data[index++] = FRAME_TYPE_TLM;                    // Eddystone frame type = Telemetry
         Data[index++] = TlmVersion;                        // TLM Version Number
         Data[index++] = (uint8_t)(TlmBatteryVoltage >> 8); // Battery Voltage[0]
         Data[index++] = (uint8_t)(TlmBatteryVoltage >> 0); // Battery Voltage[1]
         Data[index++] = (uint8_t)(TlmBeaconTemp >> 8);     // Beacon Temp[0]
         Data[index++] = (uint8_t)(TlmBeaconTemp >> 0);     // Beacon Temp[1]
         Data[index++] = (uint8_t)(TlmPduCount >> 24);      // PDU Count [0]
         Data[index++] = (uint8_t)(TlmPduCount >> 16);      // PDU Count [1]
         Data[index++] = (uint8_t)(TlmPduCount >> 8);       // PDU Count [2]
         Data[index++] = (uint8_t)(TlmPduCount >> 0);       // PDU Count [3]
         Data[index++] = (uint8_t)(TlmTimeSinceBoot >> 24); // Time Since Boot [0]
         Data[index++] = (uint8_t)(TlmTimeSinceBoot >> 16); // Time Since Boot [1]
         Data[index++] = (uint8_t)(TlmTimeSinceBoot >> 8);  // Time Since Boot [2]
         Data[index++] = (uint8_t)(TlmTimeSinceBoot >> 0);  // Time Since Boot [3]
         DBG("constructURLFrame: %d, %d", maxSize, index);
         return index;
     }
 
     /*
     *  Update the TLM frame battery voltage value
     *  @param[in] voltagemv Voltage to update the TLM field battery voltage with (in mV)
     *  @return nothing
     */
     void updateTlmBatteryVoltage(uint16_t voltagemv) {
         TlmBatteryVoltage = voltagemv;
     }
 
     /*
     *  Update the TLM frame beacon temperature
     *  @param[in] temp Temperature of beacon (in 8.8fpn)
     *  @return nothing
     */
     void updateTlmBeaconTemp(uint16_t temp) {
         TlmBeaconTemp = temp;
     }
 
     /*
     *  Update the TLM frame PDU Count field
     *  @param[in] pduCount Number of Advertisiting frames sent since powerup
     *  @return nothing
     */
     void updateTlmPduCount(uint32_t pduCount) {
         TlmPduCount = pduCount;
     }
 
     /*
     *  Update the TLM frame Time since boot in 0.1s incriments
     *  @param[in] timeSinceBoot Time since boot in 0.1s incriments
     *  @return nothing
     */
     void updateTlmTimeSinceBoot(uint32_t timeSinceBoot) {
         TlmTimeSinceBoot = timeSinceBoot;
     }
 
     /*
     * Update advertising data
     * @return true on success, false on failure
     */
     bool updateAdvPacket(uint8_t serviceData[], unsigned serviceDataLen) {
         // Fields from the Service
         DBG("Updating AdvFrame: %d", serviceDataLen);
 
         ble.clearAdvertisingPayload();
         ble.setAdvertisingType(GapAdvertisingParams::ADV_NON_CONNECTABLE_UNDIRECTED);
         ble.setAdvertisingInterval(100);
         ble.accumulateAdvertisingPayload(GapAdvertisingData::BREDR_NOT_SUPPORTED | GapAdvertisingData::LE_GENERAL_DISCOVERABLE);
         ble.accumulateAdvertisingPayload(GapAdvertisingData::COMPLETE_LIST_16BIT_SERVICE_IDS, BEACON_EDDYSTONE, sizeof(BEACON_EDDYSTONE));
         ble.accumulateAdvertisingPayload(GapAdvertisingData::SERVICE_DATA, serviceData, serviceDataLen);
 
 
         return true;
     }
 
     /*
     *   State machine for switching out frames.
     *   This function is called by the radioNotificationCallback when a frame needs to get swapped out.
     *   This function exists because of time constraints in the radioNotificationCallback, so it is effectively
     *   broken up into two functions.
     */
     void swapOutFrames(FrameTypes frameType) {
         uint8_t  serviceData[SERVICE_DATA_MAX];
         unsigned serviceDataLen = 0;
         //hard code in the eddystone UUID
         serviceData[serviceDataLen++] = BEACON_EDDYSTONE[0];
         serviceData[serviceDataLen++] = BEACON_EDDYSTONE[1];
 
         // if certain frames are not enabled, then skip them. Worst case TLM is always enabled
         switch (frameType) {
             case tlm:
                 // TLM frame
                 if (tlmIsSet) {
                     DBG("Swapping in TLM Frame: version=%x, Batt=%d, Temp = %d, PDUCnt = %d, TimeSinceBoot=%d",
                         TlmVersion,
                         TlmBatteryVoltage,
                         TlmBeaconTemp,
                         TlmPduCount,
                         TlmTimeSinceBoot);
                     serviceDataLen += constructTLMFrame(serviceData + serviceDataLen, 20);
                     DBG("\t Swapping in TLM Frame: len=%d", serviceDataLen);
                     updateAdvPacket(serviceData, serviceDataLen);
                 }
                 break;
             case url:
                 // URL Frame
                 if (urlIsSet) {
                     DBG("Swapping in URL Frame: Power: %d", defaultUrlPower);
                     serviceDataLen += constructURLFrame(serviceData + serviceDataLen, 20);
                     DBG("\t Swapping in URL Frame: len=%d ", serviceDataLen);
                     updateAdvPacket(serviceData, serviceDataLen);
                     //switchFlag = false;
                 }
                 break;
             case uid:
                 // UID Frame
                 if (uidIsSet) {
                     DBG("Swapping in UID Frame: Power: %d", defaultUidPower);
                     serviceDataLen += constructUIDFrame(serviceData + serviceDataLen, 20);
                     DBG("\t Swapping in UID Frame: len=%d", serviceDataLen);
                     updateAdvPacket(serviceData, serviceDataLen);
                     //switchFlag = false;
                 }
                 break;
             default:
                 ERR("You have not initialized a Frame yet, please initialize one before starting a beacon");
                 ERR("uidIsSet = %d, urlIsSet = %d, tlmIsSet = %d", uidIsSet, urlIsSet, tlmIsSet);
         }
     }
 
     /*
     * Callback to swap in URL frame
     */
     void urlCallback(void) {
         DBG("urlCallback");
         if (false == advLock) {
             advLock = true;
             DBG("advLock = url")
             frameIndex = url;
             swapOutFrames(frameIndex);
             ble.startAdvertising();
         } else {
             // Someone else is broadcasting, toss it into the overflow buffer to retransmit when free
             INFO("URI(%d) cannot complete, %d is currently broadcasting", url, frameIndex);
             FrameTypes x = url;
             overflow.push(x);
         }
     }
 
     /*
     * Callback to swap in UID frame
     */
     void uidCallback(void) {
         DBG("uidCallback");
         if (false == advLock) {
             advLock = true;
             DBG("advLock = uid")
             frameIndex = uid;
             swapOutFrames(frameIndex);
             ble.startAdvertising();
         } else {
             // Someone else is broadcasting, toss it into the overflow buffer to retransmit when free
             INFO("UID(%d) cannot complete, %d is currently broadcasting", uid, frameIndex);
             FrameTypes x = uid; // have to do this to satisfy cont vs volatile keywords... sigh...
             overflow.push(x);
         }
     }
 
     /*
     * Callback to swap in TLM frame
     */
     void tlmCallback(void) {
         DBG("tlmCallback");
         if (false == advLock) {
             // OK to broadcast
             advLock = true;
             DBG("advLock = tlm")
             frameIndex = tlm;
             swapOutFrames(frameIndex);
             ble.startAdvertising();
         } else {
             // Someone else is broadcasting, toss it into the overflow buffer to retransmit when free
             INFO("TLM(%d) cannot complete, %d is currently broadcasting", tlm, frameIndex);
             FrameTypes x = tlm;
             overflow.push(x);
         }
     }
 
     void stopAdvCallback(void) {
         if (overflow.empty()) {
             // if nothing left to transmit, stop
             ble.stopAdvertising();
             advLock = false; // unlock lock
         } else {
             // transmit other packets at current time index
             FrameTypes x = NONE;
             overflow.pop(x);
             INFO("Re-Transmitting %d", x);
             swapOutFrames(x);
         }
     }
 
     /*
     *  Callback from onRadioNotification(), used to update the PDUCounter and process next state.
     */
 #define EDDYSTONE_SWAPFRAME_DELAYMS 1
     void radioNotificationCallback(bool radioActive) {
         // Update PDUCount
         TlmPduCount++;
         // True just before an frame is sent, false just after a frame is sent
         if (radioActive) {
             // Do Nothing
         } else {
             // Packet has been sent, disable advertising
             stopAdv.attach_us(this, &EddystoneService::stopAdvCallback, 1);
         }
     }
 
     /*
     *   This function explicityly sets the parameters used by the Eddystone beacon.
     *   this function should be used in leu of the config service.
     *
     *   @param bleIn ble object used to broadcast eddystone information
     *   @param beaconPeriodus is how often ble broadcasts are mde, in mili seconds
     *   @param txPowerLevel sets the broadcasting power level.
     *
     */
     EddystoneService(BLEDevice &bleIn,
                      uint16_t   beaconPeriodus = 100,
                      uint8_t    txPowerIn      = 0) :
         ble(bleIn),
         advPeriodus(beaconPeriodus),
         txPower(txPowerIn),
         advLock(false),
         frameIndex(NONE) {
     }
 
     /*
     * @breif this function starts eddystone advertising based on configured frames.
     */
     void start(void) {
         // Initialize Frame transition, start with URL to pass eddystone validator app on first try
         if (urlIsSet) {
             frameIndex = url;
             urlTicker.attach(this, &EddystoneService::urlCallback, (float) advPeriodus / 1000.0f);
             DBG("attached urlCallback every %d seconds", urlAdvPeriod);
         }
         if (uidIsSet) {
             frameIndex = uid;
             uidTicker.attach(this, &EddystoneService::uidCallback, uidAdvPeriod);
             DBG("attached uidCallback every %d seconds", uidAdvPeriod);
         }
         if (tlmIsSet) {
             frameIndex = tlm;
             // Make double sure the PDUCount and TimeSinceBoot fields are set to zero at reset
             updateTlmPduCount(0);
             updateTlmTimeSinceBoot(0);
             lastBootTimerRead = 0;
             timeSinceBootTimer.start();
             tlmTicker.attach(this, &EddystoneService::tlmCallback, TlmAdvPeriod);
             DBG("attached tlmCallback every %d seconds", TlmAdvPeriod);
         }
         if (NONE == frameIndex) {
             MBED_ERROR(MBED_MAKE_ERROR(MBED_MODULE_BLE, MBED_ERROR_CODE_BLE_NO_FRAME_INITIALIZED), "No Frames were Initialized! Please initialize a frame before starting an eddystone beacon.");
         }
         //uidRFU = 0;
 
         ble.setTxPower(txPower);
         ble.gap().onRadioNotification(this, &EddystoneService::radioNotificationCallback);
     }
 
 private:
 
     // Eddystone Variables
     BLEDevice           &ble;
     uint16_t            advPeriodus;
     uint8_t             txPower;
     mbed::Timer               timeSinceBootTimer;
     volatile uint32_t   lastBootTimerRead;
     volatile bool       advLock;
     volatile FrameTypes frameIndex;
     mbed::Timeout             stopAdv;
 
 
     // URI Frame Variables
     uint8_t             defaultUriDataLength;
     UriData_t           defaultUriData;
     int8_t              defaultUrlPower;
     bool                urlIsSet;       // flag that enables / disable URI Frames
     float               urlAdvPeriod;   // how long the url frame will be advertised for
     mbed::Ticker              urlTicker;
 
     // UID Frame Variables
     UIDNamespaceID_t    defaultUidNamespaceID;
     UIDInstanceID_t     defaultUidInstanceID;
     int8_t              defaultUidPower;
     uint16_t            uidRFU;
     bool                uidIsSet;       // flag that enables / disable UID Frames
     float               uidAdvPeriod;   // how long the uid frame will be advertised for
     mbed::Ticker              uidTicker;
 
     // TLM Frame Variables
     uint8_t             TlmVersion;
     volatile uint16_t   TlmBatteryVoltage;
     volatile uint16_t   TlmBeaconTemp;
     volatile uint32_t   TlmPduCount;
     volatile uint32_t   TlmTimeSinceBoot;
     bool                tlmIsSet;          // flag that enables / disables TLM frames
     float               TlmAdvPeriod;      // number of minutes between adv frames
     mbed::Ticker              tlmTicker;
 
 public:
     /*
      *  Encode a human-readable URI into the binary format defined by URIBeacon spec (https://github.com/google/uribeacon/tree/master/specification).
      */
     static void encodeURL(const char *uriDataIn, UriData_t uriDataOut, uint8_t &sizeofURIDataOut) {
         DBG("Encode URL = %s", uriDataIn);
         const char  *prefixes[] = {
             "http://www.",
             "https://www.",
             "http://",
             "https://",
         };
         const size_t NUM_PREFIXES = sizeof(prefixes) / sizeof(char *);
         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 *);
 
         sizeofURIDataOut = 0;
         memset(uriDataOut, 0, sizeof(UriData_t));
 
         if ((uriDataIn == NULL) || (strlen(uriDataIn) == 0)) {
             return;
         }
 
         /*
          * handle prefix
          */
         for (unsigned i = 0; i < NUM_PREFIXES; i++) {
             size_t prefixLen = strlen(prefixes[i]);
             if (strncmp(uriDataIn, prefixes[i], prefixLen) == 0) {
                 uriDataOut[sizeofURIDataOut++]  = i;
                 uriDataIn                      += prefixLen;
                 break;
             }
         }
 
         /*
          * handle suffixes
          */
         while (*uriDataIn && (sizeofURIDataOut < URI_DATA_MAX)) {
             /* check for suffix match */
             unsigned i;
             for (i = 0; i < NUM_SUFFIXES; i++) {
                 size_t suffixLen = strlen(suffixes[i]);
                 if (strncmp(uriDataIn, suffixes[i], suffixLen) == 0) {
                     uriDataOut[sizeofURIDataOut++]  = i;
                     uriDataIn                      += 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. */
             INFO("Encoding URI: No Suffix Found");
             if (i == NUM_SUFFIXES) {
                 uriDataOut[sizeofURIDataOut++] = *uriDataIn;
                 ++uriDataIn;
             }
         }
     }
 };
 
 #endif // BLE_FEATURE_GATT_SERVER
 
 #endif  // SERVICES_EDDYSTONEBEACON_H_
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