Add Mecurial repository mirror link to the library documentation.
[pub/USBasp.git] / Demos / Host / Incomplete / BluetoothHost / Lib / ServiceDiscoveryProtocol.c
index c140c17..5223d29 100644 (file)
   this software.
 */
 
   this software.
 */
 
-#define  INCLUDE_FROM_SERVICEDISCOVERYPROTOCOL_C
-#include "ServiceDiscoveryProtocol.h"
+/** \file
+ *
+ *  SDP layer module. This module implements a simple Service Discovery
+ *  Protocol server, which can broadcast the device's supported services
+ *  to other Bluetooth devices upon request, so that they can determine
+ *  what services are available.
+ */
 
 
-/** Service Discovery Protocol attribute, indicationg the service's name. */
-SERVICE_ATTRIBUTE_TEXT(SDP_Attribute_Name,         "SDP");
-/** Service Discovery Protocol attribute, indicationg the service's description. */
-SERVICE_ATTRIBUTE_TEXT(SDP_Attribute_Description,  "BT Service Discovery");
-/** Service Discovery Protocol attribute, indicationg the service's availability. */
-SERVICE_ATTRIBUTE_LEN8(SDP_Attribute_Availability, SDP_DATATYPE_UnsignedInt, 1, {0xFF});
-/** Service Discovery Protocol attribute table, listing all supported attributes of the service. */
-const ServiceAttributeTable_t SDP_Attribute_Table[] PROGMEM =
-       {
-               {.AttributeID = SDP_ATTRIBUTE_NAME        , .Data = &SDP_Attribute_Name},
-               {.AttributeID = SDP_ATTRIBUTE_DESCRIPTION , .Data = &SDP_Attribute_Description},
-               {.AttributeID = SDP_ATTRIBUTE_AVAILABILITY, .Data = &SDP_Attribute_Availability},
-               SERVICE_ATTRIBUTE_TABLE_TERMINATOR
-       };
+/*
+       TODO: Honor remote device's buffer size constraints via continuation state
+ */
 
 
-/** RFCOMM Service attribute, indicationg the service's name. */
-SERVICE_ATTRIBUTE_TEXT(RFCOMM_Attribute_Name,         "RFCOMM");
-/** RFCOMM Service attribute, indicationg the service's description. */
-SERVICE_ATTRIBUTE_TEXT(RFCOMM_Attribute_Description,  "Virtual Serial");
-/** RFCOMM Service attribute, indicationg the service's availability. */
-SERVICE_ATTRIBUTE_LEN8(RFCOMM_Attribute_Availability, SDP_DATATYPE_UnsignedInt, 1, {0xFF});
-/** RFCOMM Service attribute table, listing all supported attributes of the service. */
-const ServiceAttributeTable_t RFCOMM_Attribute_Table[] PROGMEM =
-       {
-               {.AttributeID = SDP_ATTRIBUTE_NAME        , .Data = &RFCOMM_Attribute_Name},
-               {.AttributeID = SDP_ATTRIBUTE_DESCRIPTION , .Data = &RFCOMM_Attribute_Description},
-               {.AttributeID = SDP_ATTRIBUTE_AVAILABILITY, .Data = &RFCOMM_Attribute_Availability},
-               SERVICE_ATTRIBUTE_TABLE_TERMINATOR
-       };
+#define  INCLUDE_FROM_SERVICEDISCOVERYPROTOCOL_C
+#include "ServiceDiscoveryProtocol.h"
 
 
-/** Master service table, listing all supported services (and their attribute tables) of the device, including
- *  each service's UUID.
- */
-const ServiceTable_t SDP_Services_Table[] =
+/** Service attribute table list, containing a pointer to each service attribute table the device contains */
+const ServiceAttributeTable_t* SDP_Services_Table[] PROGMEM =
        {
        {
-               {   // 128-bit UUID for the SDP service
-                       .UUID  = {BASE_96BIT_UUID, 0x01, 0x00, 0x00, 0x00},
-                       .AttributeTable = &SDP_Attribute_Table,
-               },
-               {   // 128-bit UUID for the RFCOMM service
-                       .UUID  = {BASE_96BIT_UUID, 0x03, 0x00, 0x00, 0x00},
-                       .AttributeTable = &RFCOMM_Attribute_Table,
-               },
+               SerialPort_Attribute_Table,
        };
 
 /** Base UUID value common to all standardized Bluetooth services */
        };
 
 /** Base UUID value common to all standardized Bluetooth services */
-const uint8_t BaseUUID[] = {BASE_96BIT_UUID, 0x00, 0x00, 0x00, 0x00};
+const UUID_t BaseUUID PROGMEM = {0x00000000, BASE_80BIT_UUID};
 
 
+/** Initializes the SDP service, ready for new connections from a SDP client. */
+void SDP_Initialize(void)
+{
+       /* Not currently used */
+}
 
 /** Main Service Discovery Protocol packet processing routine. This function processes incomming SDP packets from
  *  a connected Bluetooth device, and sends back appropriate responses to allow other devices to determine the
 
 /** Main Service Discovery Protocol packet processing routine. This function processes incomming SDP packets from
  *  a connected Bluetooth device, and sends back appropriate responses to allow other devices to determine the
@@ -87,7 +65,7 @@ const uint8_t BaseUUID[] = {BASE_96BIT_UUID, 0x00, 0x00, 0x00, 0x00};
  *  \param[in]  Data     Incomming packet data containing the SDP request
  *  \param[in]  Channel  Channel the request was issued to by the remote device
  */
  *  \param[in]  Data     Incomming packet data containing the SDP request
  *  \param[in]  Channel  Channel the request was issued to by the remote device
  */
-void ServiceDiscovery_ProcessPacket(void* Data, Bluetooth_Channel_t* Channel)
+void SDP_ProcessPacket(void* Data, Bluetooth_Channel_t* const Channel)
 {
        SDP_PDUHeader_t* SDPHeader = (SDP_PDUHeader_t*)Data;
        SDPHeader->ParameterLength = SwapEndian_16(SDPHeader->ParameterLength);
 {
        SDP_PDUHeader_t* SDPHeader = (SDP_PDUHeader_t*)Data;
        SDPHeader->ParameterLength = SwapEndian_16(SDPHeader->ParameterLength);
@@ -96,43 +74,217 @@ void ServiceDiscovery_ProcessPacket(void* Data, Bluetooth_Channel_t* Channel)
        BT_SDP_DEBUG(2, "-- PDU ID: 0x%02X", SDPHeader->PDU);
        BT_SDP_DEBUG(2, "-- Param Length: 0x%04X", SDPHeader->ParameterLength);
 
        BT_SDP_DEBUG(2, "-- PDU ID: 0x%02X", SDPHeader->PDU);
        BT_SDP_DEBUG(2, "-- Param Length: 0x%04X", SDPHeader->ParameterLength);
 
+       /* Dispatch to the correct processing routine for the given SDP packet type */
        switch (SDPHeader->PDU)
        {
                case SDP_PDU_SERVICESEARCHREQUEST:
        switch (SDPHeader->PDU)
        {
                case SDP_PDU_SERVICESEARCHREQUEST:
-                       ServiceDiscovery_ProcessServiceSearch(SDPHeader, Channel);
+                       SDP_ProcessServiceSearch(SDPHeader, Channel);
                        break;          
                case SDP_PDU_SERVICEATTRIBUTEREQUEST:
                        break;          
                case SDP_PDU_SERVICEATTRIBUTEREQUEST:
-                       ServiceDiscovery_ProcessServiceAttribute(SDPHeader, Channel);
+                       SDP_ProcessServiceAttribute(SDPHeader, Channel);
                        break;
                case SDP_PDU_SERVICESEARCHATTRIBUTEREQUEST:
                        break;
                case SDP_PDU_SERVICESEARCHATTRIBUTEREQUEST:
-                       ServiceDiscovery_ProcessServiceSearchAttribute(SDPHeader, Channel);
+                       SDP_ProcessServiceSearchAttribute(SDPHeader, Channel);
                        break;
        }
 }
 
                        break;
        }
 }
 
-static void ServiceDiscovery_ProcessServiceSearch(SDP_PDUHeader_t* SDPHeader, Bluetooth_Channel_t* Channel)
+/** Internal processing routine for SDP Service Search Requests.
+ *
+ *  \param[in] SDPHeader  Pointer to the start of the issued SDP request
+ *  \param[in] Channel    Pointer to the Bluetooth channel structure the request was issued to
+ */
+static void SDP_ProcessServiceSearch(const SDP_PDUHeader_t* const SDPHeader, Bluetooth_Channel_t* const Channel)
 {
 {
+       const void* CurrentParameter = ((void*)SDPHeader + sizeof(SDP_PDUHeader_t));
+
        BT_SDP_DEBUG(1, "<< Service Search");
        BT_SDP_DEBUG(1, "<< Service Search");
+
+       /* Retrieve the list of search UUIDs from the request */
+       uint8_t UUIDList[12][UUID_SIZE_BYTES];
+       uint8_t TotalUUIDs = SDP_GetUUIDList(UUIDList, &CurrentParameter);
+       BT_SDP_DEBUG(2, "-- Total UUIDs: %d", TotalUUIDs);
+       
+       /* Retrieve the maximum service record reponse count from the request */
+       uint16_t MaxServiceRecordCount = SDP_ReadData16(&CurrentParameter);
+       BT_SDP_DEBUG(2, "-- Max Return Service Count: 0x%04X", MaxServiceRecordCount);
+       
+       struct
+       {
+               SDP_PDUHeader_t SDPHeader;
+               uint16_t        TotalServiceRecordCount;
+               uint16_t        CurrentServiceRecordCount;
+               uint8_t         ResponseData[100];
+       } ResponsePacket;
+       
+       uint8_t AddedServiceHandles = 0;
+
+       /* Create a pointer to the buffer to indicate the current location for response data to be added */
+       void* CurrResponsePos = ResponsePacket.ResponseData;
+
+       /* Search through the global service list an item at a time */
+       for (uint8_t CurrTableItem = 0; CurrTableItem < (sizeof(SDP_Services_Table) / sizeof(void*)); CurrTableItem++)
+       {
+               /* Read in a pointer to the current UUID table entry's Attribute table */
+               ServiceAttributeTable_t* CurrAttributeTable = pgm_read_ptr(&SDP_Services_Table[CurrTableItem]);
+
+               if (!(SDP_SearchServiceTable(UUIDList, TotalUUIDs, CurrAttributeTable)))
+                 continue;
+
+               BT_SDP_DEBUG(2, " -- Found search match in table");
+
+               /* Retrieve a PROGMEM pointer to the value of the service's record handle */
+               const void* AttributeValue = SDP_GetAttributeValue(CurrAttributeTable, SDP_ATTRIBUTE_ID_SERVICERECORDHANDLE);
+
+               /* Copy over the service record handle to the response list */
+               uint8_t AttrHeaderSize;
+               uint8_t AttrSize = SDP_GetLocalAttributeContainerSize(AttributeValue, &AttrHeaderSize);
+               memcpy_P(CurrResponsePos, AttributeValue + AttrHeaderSize, AttrSize);
+               CurrResponsePos += AttrHeaderSize + AttrSize;
+               
+               AddedServiceHandles++;
+       }
+
+       /* Continuation state - always zero */
+       SDP_WriteData8(&CurrResponsePos, 0);
+
+       /* Fill out the service record count values in the returned packet */
+       ResponsePacket.TotalServiceRecordCount   = SwapEndian_16(AddedServiceHandles);
+       ResponsePacket.CurrentServiceRecordCount = ResponsePacket.TotalServiceRecordCount;
+
+       /* Calculate the total parameter length that is to be sent, including the fixed return parameters, the created service
+          handle list and the SDP continuation state */
+       uint16_t ParamLength = (ResponsePacket.CurrentServiceRecordCount << 2) +
+                               sizeof(ResponsePacket.CurrentServiceRecordCount) +
+                               sizeof(ResponsePacket.TotalServiceRecordCount) +
+                               sizeof(uint8_t);
+
+       /* Fill in the response packet's header */
+       ResponsePacket.SDPHeader.PDU             = SDP_PDU_SERVICESEARCHRESPONSE;
+       ResponsePacket.SDPHeader.TransactionID   = SDPHeader->TransactionID;
+       ResponsePacket.SDPHeader.ParameterLength = SwapEndian_16(ParamLength);
+
+       BT_SDP_DEBUG(1, ">> Service Search Response");
+
+       /* Send the completed response packet to the sender */
+       Bluetooth_SendPacket(&ResponsePacket, (sizeof(ResponsePacket.SDPHeader) + ParamLength), Channel);
 }
 
 }
 
-static void ServiceDiscovery_ProcessServiceAttribute(SDP_PDUHeader_t* SDPHeader, Bluetooth_Channel_t* Channel)
+/** Internal processing routine for SDP Service Attribute Requests.
+ *
+ *  \param[in] SDPHeader  Pointer to the start of the issued SDP request
+ *  \param[in] Channel    Pointer to the Bluetooth channel structure the request was issued to
+ */
+static void SDP_ProcessServiceAttribute(const SDP_PDUHeader_t* const SDPHeader, Bluetooth_Channel_t* const Channel)
 {
 {
+       const void* CurrentParameter = ((void*)SDPHeader + sizeof(SDP_PDUHeader_t));
+
        BT_SDP_DEBUG(1, "<< Service Attribute");
        BT_SDP_DEBUG(1, "<< Service Attribute");
+
+       /* Retrieve the service handle whose attributes are to be examined */
+       uint32_t ServiceHandle = SDP_ReadData32(&CurrentParameter);
+       BT_SDP_DEBUG(2, "-- Service Handle: 0x%08lX", ServiceHandle);
+       
+       /* Retrieve the maximum Attribute reponse size from the request */
+       uint16_t MaxAttributeSize = SDP_ReadData16(&CurrentParameter);
+       BT_SDP_DEBUG(2, "-- Max Return Attribute Bytes: 0x%04X", MaxAttributeSize);
+       
+       /* Retrieve the list of Attributes from the request */
+       uint16_t AttributeList[8][2];
+       uint8_t  TotalAttributes = SDP_GetAttributeList(AttributeList, &CurrentParameter);
+       BT_SDP_DEBUG(2, "-- Total Attributes: %d", TotalAttributes);
+
+       struct
+       {
+               SDP_PDUHeader_t SDPHeader;
+               uint16_t        AttributeListByteCount;
+               uint8_t         ResponseData[100];
+       } ResponsePacket;
+
+       /* Create a pointer to the buffer to indicate the current location for response data to be added */
+       void* CurrResponsePos = ResponsePacket.ResponseData;
+
+       /* Clamp the maximum attribute size to the size of the allocated buffer */
+       if (MaxAttributeSize > sizeof(ResponsePacket.ResponseData))
+         MaxAttributeSize = sizeof(ResponsePacket.ResponseData);
+
+       uint16_t TotalResponseSize = 0;
+
+       /* Search through the global UUID list an item at a time */
+       for (uint8_t CurrTableItem = 0; CurrTableItem < (sizeof(SDP_Services_Table) / sizeof(void*)); CurrTableItem++)
+       {
+               /* Read in a pointer to the current UUID table entry's Attribute table */
+               ServiceAttributeTable_t* CurrAttributeTable = pgm_read_ptr(&SDP_Services_Table[CurrTableItem]);
+               
+               /* Retrieve a PROGMEM pointer to the value of the Service Record Handle */
+               const void* ServiceRecord = SDP_GetAttributeValue(CurrAttributeTable, SDP_ATTRIBUTE_ID_SERVICERECORDHANDLE);
+               
+               /* Get the size of the header for the Service Record Handle */
+               uint8_t AttrHeaderSize;
+               SDP_GetLocalAttributeContainerSize(ServiceRecord, &AttrHeaderSize);
+               
+               /* Retrieve the endian-swapped service handle of the current service being examined */
+               uint32_t CurrServiceHandle = SwapEndian_32(pgm_read_dword(ServiceRecord + AttrHeaderSize));
+               
+               /* Check if the current service in the service table has the requested service handle */
+               if (ServiceHandle == CurrServiceHandle)
+               {
+                       /* Add the listed attributes for the found UUID to the response */
+                       TotalResponseSize = SDP_AddListedAttributesToResponse(CurrAttributeTable, AttributeList, TotalAttributes,
+                                                                         &CurrResponsePos);
+                       
+                       /* Requested service found, abort the search through the service table */
+                       break;
+               }
+       }
+
+       /* Continuation state - always zero */
+       SDP_WriteData8(&CurrResponsePos, 0);
+
+       /* Set the total response list size to the size of the outer container plus its header size and continuation state */
+       ResponsePacket.AttributeListByteCount    = SwapEndian_16(TotalResponseSize);
+
+       /* Calculate the total parameter length that is to be sent, including the fixed return parameters, the created attribute
+          value list and the SDP continuation state */
+       uint16_t ParamLength = (sizeof(ResponsePacket.AttributeListByteCount) + TotalResponseSize + sizeof(uint8_t));
+       
+       /* Fill in the response packet's header */
+       ResponsePacket.SDPHeader.PDU             = SDP_PDU_SERVICEATTRIBUTERESPONSE;
+       ResponsePacket.SDPHeader.TransactionID   = SDPHeader->TransactionID;
+       ResponsePacket.SDPHeader.ParameterLength = SwapEndian_16(ParamLength);
+
+       BT_SDP_DEBUG(1, ">> Service Attribute Response");
+       BT_SDP_DEBUG(2, "-- Param Len 0x%04X", ParamLength);
+
+       /* Send the completed response packet to the sender */
+       Bluetooth_SendPacket(&ResponsePacket, (sizeof(ResponsePacket.SDPHeader) + ParamLength), Channel);
 }
 
 }
 
-static void ServiceDiscovery_ProcessServiceSearchAttribute(SDP_PDUHeader_t* SDPHeader, Bluetooth_Channel_t* Channel)
+/** Internal processing routine for SDP Service Search Attribute Requests.
+ *
+ *  \param[in] SDPHeader  Pointer to the start of the issued SDP request
+ *  \param[in] Channel    Pointer to the Bluetooth channel structure the request was issued to
+ */
+static void SDP_ProcessServiceSearchAttribute(const SDP_PDUHeader_t* const SDPHeader, Bluetooth_Channel_t* const Channel)
 {
        const void* CurrentParameter = ((void*)SDPHeader + sizeof(SDP_PDUHeader_t));
        
        BT_SDP_DEBUG(1, "<< Service Search Attribute");
 
 {
        const void* CurrentParameter = ((void*)SDPHeader + sizeof(SDP_PDUHeader_t));
        
        BT_SDP_DEBUG(1, "<< Service Search Attribute");
 
+       /* Retrieve the list of search UUIDs from the request */
        uint8_t UUIDList[12][UUID_SIZE_BYTES];
        uint8_t UUIDList[12][UUID_SIZE_BYTES];
-       uint8_t TotalUUIDs = ServiceDiscovery_GetUUIDList(UUIDList, &CurrentParameter);
+       uint8_t TotalUUIDs = SDP_GetUUIDList(UUIDList, &CurrentParameter);
        BT_SDP_DEBUG(2, "-- Total UUIDs: %d", TotalUUIDs);
        
        BT_SDP_DEBUG(2, "-- Total UUIDs: %d", TotalUUIDs);
        
-       uint16_t MaxAttributeSize = ServiceDiscovery_Read16BitParameter(&CurrentParameter);
+       /* Retrieve the maximum Attribute reponse size from the request */
+       uint16_t MaxAttributeSize = SDP_ReadData16(&CurrentParameter);
        BT_SDP_DEBUG(2, "-- Max Return Attribute Bytes: 0x%04X", MaxAttributeSize);
        BT_SDP_DEBUG(2, "-- Max Return Attribute Bytes: 0x%04X", MaxAttributeSize);
-
+       
+       /* Retrieve the list of Attributes from the request */
+       uint16_t AttributeList[8][2];
+       uint8_t  TotalAttributes = SDP_GetAttributeList(AttributeList, &CurrentParameter);
+       BT_SDP_DEBUG(2, "-- Total Attributes: %d", TotalAttributes);
+       
        struct
        {
                SDP_PDUHeader_t SDPHeader;
        struct
        {
                SDP_PDUHeader_t SDPHeader;
@@ -140,90 +292,335 @@ static void ServiceDiscovery_ProcessServiceSearchAttribute(SDP_PDUHeader_t* SDPH
                uint8_t         ResponseData[100];
        } ResponsePacket;
        
                uint8_t         ResponseData[100];
        } ResponsePacket;
        
+       /* Create a pointer to the buffer to indicate the current location for response data to be added */
+       void* CurrResponsePos = ResponsePacket.ResponseData;
+
+       /* Clamp the maximum attribute size to the size of the allocated buffer */
        if (MaxAttributeSize > sizeof(ResponsePacket.ResponseData))
          MaxAttributeSize = sizeof(ResponsePacket.ResponseData);
        if (MaxAttributeSize > sizeof(ResponsePacket.ResponseData))
          MaxAttributeSize = sizeof(ResponsePacket.ResponseData);
-         
-       ResponsePacket.AttributeListByteCount    = ServiceDiscovery_ProcessAttributes(UUIDList, TotalUUIDs,
-                                                                                     ResponsePacket.ResponseData,
-                                                                                     MaxAttributeSize, &CurrentParameter);
+
+       /* Add the outer Data Element Sequence header for all of the retrieved Attributes */
+       uint16_t* TotalResponseSize = SDP_AddSequence16(&CurrResponsePos);
+       
+       /* Search through the global service list an item at a time */
+       for (uint8_t CurrTableItem = 0; CurrTableItem < (sizeof(SDP_Services_Table) / sizeof(void*)); CurrTableItem++)
+       {
+               /* Read in a pointer to the current UUID table entry's Attribute table */
+               ServiceAttributeTable_t* CurrAttributeTable = pgm_read_ptr(&SDP_Services_Table[CurrTableItem]);
+
+               if (!(SDP_SearchServiceTable(UUIDList, TotalUUIDs, CurrAttributeTable)))
+                 continue;
+                 
+               BT_SDP_DEBUG(2, " -- Found search match in table");
+
+               /* Add the listed attributes for the found UUID to the response */
+               *TotalResponseSize += SDP_AddListedAttributesToResponse(CurrAttributeTable, AttributeList, TotalAttributes, 
+                                                                       &CurrResponsePos);
+       }
+       
+       /* Continuation state - always zero */
+       SDP_WriteData8(&CurrResponsePos, 0);
+
+       /* Set the total response list size to the size of the outer container plus its header size and continuation state */
+       ResponsePacket.AttributeListByteCount    = SwapEndian_16(3 + *TotalResponseSize);
+
+       /* Calculate the total parameter length that is to be sent, including the fixed return parameters, the created attribute
+          value list and the SDP continuation state */
+       uint16_t ParamLength = (sizeof(ResponsePacket.AttributeListByteCount) + 
+                               (3 + *TotalResponseSize) +
+                               sizeof(uint8_t));
+
+       /* Flip the endianness of the container's size */
+       *TotalResponseSize = SwapEndian_16(*TotalResponseSize);
+
+       /* Fill in the response packet's header */
        ResponsePacket.SDPHeader.PDU             = SDP_PDU_SERVICESEARCHATTRIBUTERESPONSE;
        ResponsePacket.SDPHeader.TransactionID   = SDPHeader->TransactionID;
        ResponsePacket.SDPHeader.PDU             = SDP_PDU_SERVICESEARCHATTRIBUTERESPONSE;
        ResponsePacket.SDPHeader.TransactionID   = SDPHeader->TransactionID;
-       ResponsePacket.SDPHeader.ParameterLength = (ResponsePacket.AttributeListByteCount + sizeof(ResponsePacket.AttributeListByteCount));
+       ResponsePacket.SDPHeader.ParameterLength = SwapEndian_16(ParamLength);
+
+       BT_SDP_DEBUG(1, ">> Service Search Attribute Response");
+       BT_SDP_DEBUG(2, "-- Param Len 0x%04X", ParamLength);
 
 
-       Bluetooth_SendPacket(&ResponsePacket, (sizeof(ResponsePacket.SDPHeader) + ResponsePacket.SDPHeader.ParameterLength),
-                            Channel);
+       /* Send the completed response packet to the sender */
+       Bluetooth_SendPacket(&ResponsePacket, (sizeof(ResponsePacket.SDPHeader) + ParamLength), Channel);
 }
 
 }
 
-static uint8_t ServiceDiscovery_ProcessAttributes(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs, uint8_t* ResponseBuffer,
-                                                  uint8_t MaxResponseSize, const void** CurrentParameter)
+/** Adds all the Attributes in the given service table to the response that appear in the Attribute table.
+ *
+ *  \param[in]  AttributeTable   Pointer to an Attribute table for the service to examine
+ *  \param[in]  AttributeList    Pointer to a list of Attribute ranges
+ *  \param[in]  TotalAttributes  Number of Attributes stored in the Attribute list
+ *  \param[out] BufferPos       Pointer to the output buffer position where the retrieved attributes are to be stored
+ *
+ *  \return Number of bytes added to the output buffer
+ */
+static uint16_t SDP_AddListedAttributesToResponse(const ServiceAttributeTable_t* AttributeTable, uint16_t AttributeList[][2],
+                                                  const uint8_t TotalAttributes, void** const BufferPos)
 {
 {
-       uint16_t* AttributeResponseSize = ServiceDiscovery_AddDataElementHeader(&ResponseBuffer, SDP_DATATYPE_UnsignedInt);
-       uint8_t   ElementHeaderSize;
+       uint16_t TotalResponseSize;
 
 
-       uint16_t AttributeIDListLength = ServiceDiscovery_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
-       BT_SDP_DEBUG(2, "-- Total Attribute Length: 0x%04X", AttributeIDListLength);
-       while (AttributeIDListLength)
+       /* Add an inner Data Element Sequence header for the current services's found Attributes */
+       uint16_t* AttributeListSize = SDP_AddSequence16(BufferPos);
+
+       /* Search through the list of Attributes one at a time looking for values in the current UUID's Attribute table */
+       for (uint8_t CurrAttribute = 0; CurrAttribute < TotalAttributes; CurrAttribute++)
        {
        {
-               uint8_t  AttributeLength = ServiceDiscovery_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
-               uint32_t Attribute       = 0;
+               uint16_t* AttributeIDRange = AttributeList[CurrAttribute];
+               void*     AttributeValue;
                
                
-               memcpy(&((char*)&Attribute)[sizeof(uint32_t) - AttributeLength], *CurrentParameter, AttributeLength);
+               /* Look through the current service's attribute list, examining all the attributes */
+               while ((AttributeValue = pgm_read_ptr(&AttributeTable->Data)) != NULL)
+               {
+                       /* Get the current Attribute's ID from the current attribute table entry */
+                       uint16_t CurrAttributeID = pgm_read_word(&AttributeTable->AttributeID);
+
+                       /* Check if the current Attribute's ID is within the current Attribute range */
+                       if ((CurrAttributeID >= AttributeIDRange[0]) && (CurrAttributeID <= AttributeIDRange[1]))
+                       {
+                               /* Increment the current UUID's returned Attribute container size by the number of added bytes */
+                               *AttributeListSize += SDP_AddAttributeToResponse(CurrAttributeID, AttributeValue, BufferPos);                   
+                       }
+                       
+                       AttributeTable++;
+               }
+       }
+
+       /* Record the total number of added bytes to the buffer */
+       TotalResponseSize = 3 + *AttributeListSize;
 
 
-               BT_SDP_DEBUG(2, "-- Attribute(%d): 0x%08lX", AttributeLength, Attribute);
+       /* Fix endianness of the added attribute data element sequence */
+       *AttributeListSize = SwapEndian_16(*AttributeListSize);
+
+       return TotalResponseSize;
+}
+
+/** Adds the given attribute ID and value to the reponse buffer, and advances the response buffer pointer past the added data.
+ *
+ *  \param[in] AttributeID          Attribute ID to add to the response buffer
+ *  \param[in] AttributeValue       Pointer to the start of the Attribute's value, located in PROGMEM
+ *  \param[in, out] ResponseBuffer  Pointer to a buffer where the Attribute and Attribute Value is to be added
+ *
+ *  \return Number of bytes added to the response buffer
+ */
+static uint16_t SDP_AddAttributeToResponse(const uint16_t AttributeID, const void* AttributeValue, void** ResponseBuffer)
+{
+       /* Retrieve the size of the attribute value from its container header */
+       uint8_t  AttributeHeaderLength;
+       uint16_t AttributeValueLength = SDP_GetLocalAttributeContainerSize(AttributeValue, &AttributeHeaderLength);
+       
+       BT_SDP_DEBUG(2, " -- Add Attribute (0x%04X) 0x%04X", (AttributeHeaderLength + AttributeValueLength), AttributeID);
+
+       /* Add a Data Element header to the response for the Attribute ID */
+       SDP_WriteData8(ResponseBuffer, (SDP_DATATYPE_UnsignedInt | SDP_DATASIZE_16Bit));
+       
+       /* Add the Attribute ID to the created Data Element */
+       SDP_WriteData16(ResponseBuffer, AttributeID);
+       
+       /* Copy over the Attribute value Data Element container to the response */
+       memcpy_P(*ResponseBuffer, AttributeValue, AttributeHeaderLength + AttributeValueLength);
+       *ResponseBuffer += AttributeHeaderLength + AttributeValueLength;
+       
+       return (sizeof(uint8_t) + sizeof(uint16_t) + AttributeHeaderLength + AttributeValueLength);
+}
+
+/** Retrieves a pointer to the value of the given Attribute ID from the given Attribute table.
+ *
+ *  \param[in] AttributeTable  Pointer to the Attribute table to search in
+ *  \param[in] AttributeID     Attribute ID to search for within the table
+ *
+ *  \return Pointer to the start of the Attribute's value if found within the table, NULL otherwise
+ */
+static void* SDP_GetAttributeValue(const ServiceAttributeTable_t* AttributeTable, const uint16_t AttributeID)
+{
+       void* CurrTableItemData;
+       
+       /* Search through the current Attribute table, abort when the terminator item has been reached */
+       while ((CurrTableItemData = pgm_read_ptr(&AttributeTable->Data)) != NULL)
+       {
+               /* Check if the current Attribute ID matches the search ID - if so return a pointer to it */
+               if (pgm_read_word(&AttributeTable->AttributeID) == AttributeID)
+                 return CurrTableItemData;
                
                
-               *AttributeResponseSize += ServiceDiscovery_GetAttribute(UUIDList, TotalUUIDs, Attribute, &ResponseBuffer,
-                                                                       (MaxResponseSize - *AttributeResponseSize));
+               AttributeTable++;
+       }
+                       
+       return NULL;
+}
+
+/** Retrieves the Attribute table for the given UUID list if it exists.
+ *
+ *  \param[in] UUIDList            List of UUIDs which must be matched within the service attribute table
+ *  \param[in] TotalUUIDs          Total number of UUIDs stored in the UUID list
+ *  \param[in] CurrAttributeTable  Pointer to the service attribute table to search through
+ *
+ *  \return True if all the UUIDs given in the UUID list appear in the given attribute table, false otherwise
+ */
+static bool SDP_SearchServiceTable(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs,
+                                              const ServiceAttributeTable_t* CurrAttributeTable)
+{
+       bool UUIDMatch[TotalUUIDs];     
        
        
-               AttributeIDListLength -= (AttributeLength + ElementHeaderSize);
-               *CurrentParameter     += AttributeLength;
+       /* Set all the match flags to false (not matched) before starting the search */
+       memset(UUIDMatch, false, sizeof(UUIDMatch));
+
+       const void* CurrAttribute;
+       
+       /* Search through the current attribute table, checking each attribute value for UUID matches */
+       while ((CurrAttribute = pgm_read_ptr(&CurrAttributeTable->Data)) != NULL)
+       {
+               SDP_CheckUUIDMatch(UUIDList, TotalUUIDs, UUIDMatch, CurrAttribute);
+               CurrAttributeTable++;
+       }
+
+       /* Determine how many UUID matches in the list we have found */
+       uint8_t UUIDMatches = 0;
+       for (uint8_t i = 0; i < TotalUUIDs; i++)
+       {
+               if (UUIDMatch[i])
+                 UUIDMatches++;
        }
        
        }
        
-       return *AttributeResponseSize;
+       /* If all UUIDs have been matched to the current service, return true */
+       return (UUIDMatches == TotalUUIDs);
 }
 
 }
 
-static uint8_t ServiceDiscovery_GetAttribute(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs, const uint32_t Attribute,
-                                             uint8_t** DataBuffer, uint8_t BufferLen)
+/** Recursively upwraps the given locally stored attribute (in PROGMEM space), searching for UUIDs to match against
+ *  the given UUID list. As matches are found, they are indicated in the UUIDMatch flag list.
+ *
+ *  \param[in]      UUIDList       List of UUIDs which must be matched within the service attribute table
+ *  \param[in]      TotalUUIDs     Total number of UUIDs stored in the UUID list
+ *  \param[in, out] UUIDMatch      Array of flags indicating which UUIDs in the list have already been matched
+ *  \param[in]      CurrAttribute  Pointer to the current attribute to search through
+ *
+ *  \return True if all the UUIDs given in the UUID list appear in the given attribute table, false otherwise
+ */
+static void SDP_CheckUUIDMatch(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs, bool UUIDMatch[],
+                               const void* CurrAttribute)
 {
 {
-       for (uint8_t CurrTableItem = 0; CurrTableItem < (sizeof(SDP_Services_Table) / sizeof(ServiceTable_t)); CurrTableItem++)
+       uint8_t CurrAttributeType = (pgm_read_byte(CurrAttribute) & ~0x07);
+
+       /* Check the data type of the current attribute value - if UUID, compare, if Sequence, unwrap and recurse */
+       if (CurrAttributeType == SDP_DATATYPE_UUID)
        {
        {
-               for (uint8_t CurrUUIDIndex = 0; CurrUUIDIndex < TotalUUIDs; CurrUUIDIndex++)
+               /* Look for matches in the UUID list against the current attribute UUID value */
+               for (uint8_t i = 0; i < TotalUUIDs; i++)
                {
                {
-                       if (!(memcmp(SDP_Services_Table[CurrTableItem].UUID, UUIDList[CurrUUIDIndex], UUID_SIZE_BYTES)))
+                       /* Check if the current unmatched UUID is identical to the search UUID */
+                       if (!(UUIDMatch[i]) && !(memcmp_P(UUIDList[i], (CurrAttribute + 1), UUID_SIZE_BYTES)))
                        {
                        {
-                               const ServiceAttributeTable_t* AttributeTable = SDP_Services_Table[CurrTableItem].AttributeTable;
-
-                               // TODO: Process attribute table
-                               BT_SDP_DEBUG(2, "FOUND UUID IN TABLE");
-
+                               /* Indicate match found for the current attribute UUID and early-abort */
+                               UUIDMatch[i] = true;
                                break;
                        }
                }
        }
                                break;
                        }
                }
        }
+       else if (CurrAttributeType == SDP_DATATYPE_Sequence)
+       {
+               uint8_t  SequenceHeaderSize;
+               uint16_t SequenceSize = SDP_GetLocalAttributeContainerSize(CurrAttribute, &SequenceHeaderSize);
+               
+               CurrAttribute += SequenceHeaderSize;
                
                
-       return 0;
+               /* Recursively unwrap the sequence container, and re-search its contents for UUIDs */
+               while (SequenceSize)
+               {
+                       uint8_t  InnerHeaderSize;
+                       uint16_t InnerSize = SDP_GetLocalAttributeContainerSize(CurrAttribute, &InnerHeaderSize);
+                       
+                       SDP_CheckUUIDMatch(UUIDList, TotalUUIDs, UUIDMatch, CurrAttribute);
+                                               
+                       SequenceSize  -= InnerHeaderSize + InnerSize;
+                       CurrAttribute += InnerHeaderSize + InnerSize;
+               }
+       }       
+}
+
+/** Reads in the collection of Attribute ranges from the input buffer's Data Element Sequence container, into the given 
+ *  Attribute list for later use. Once complete, the input buffer pointer is advanced to the end of the Attribute container.
+ *
+ *  \param[out] AttributeList     Pointer to a buffer where the list of Attribute ranges are to be stored
+ *  \param[in]  CurrentParameter  Pointer to a Buffer containing a Data Element Sequence of Attribute and Attribute Range elements
+ *
+ *  \return Total number of Attribute ranges stored in the Data Element Sequence
+ */
+static uint8_t SDP_GetAttributeList(uint16_t AttributeList[][2], const void** const CurrentParameter)
+{
+       uint8_t ElementHeaderSize;
+       uint8_t TotalAttributes = 0;
+
+       /* Retrieve the total size of the Attribute container, and unwrap the outer Data Element Sequence container */
+       uint16_t AttributeIDListLength = SDP_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
+       BT_SDP_DEBUG(2, "-- Total Attribute Length: 0x%04X", AttributeIDListLength);
+       while (AttributeIDListLength)
+       {
+               /* Retrieve the size of the next Attribute in the container and get a pointer to the next free Attribute element in the list */
+               uint16_t* CurrentAttributeRange = AttributeList[TotalAttributes++];
+               uint8_t   AttributeLength       = SDP_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
+               
+               /* Copy over the starting Attribute ID and (if it the current element is a range) the ending Attribute ID */
+               memcpy(&CurrentAttributeRange[0], *CurrentParameter, AttributeLength);
+               
+               /* If the element is not an Attribute Range, copy over the starting ID to the ending ID to make a range of 1 */
+               if (AttributeLength == 2)
+                 CurrentAttributeRange[1] = CurrentAttributeRange[0];
+
+               /* Swap the endianness of the attribute range values */
+               CurrentAttributeRange[0] = SwapEndian_16(CurrentAttributeRange[0]);
+               CurrentAttributeRange[1] = SwapEndian_16(CurrentAttributeRange[1]);
+
+               BT_SDP_DEBUG(2, "-- Attribute: 0x%04X-0x%04X", CurrentAttributeRange[0], CurrentAttributeRange[1]);
+               
+               AttributeIDListLength -= (AttributeLength + ElementHeaderSize);
+               *CurrentParameter     += AttributeLength;
+       }
+       
+       return TotalAttributes;
 }
 
 }
 
-static uint8_t ServiceDiscovery_GetUUIDList(uint8_t UUIDList[][UUID_SIZE_BYTES], const void** CurrentParameter)
+/** Reads in the collection of UUIDs from the input buffer's Data Element Sequence container, into the given 
+ *  UUID list for later use. Once complete, the input buffer pointer is advanced to the end of the UUID container.
+ *
+ *  \param[out] UUIDList          Pointer to a buffer where the list of UUIDs are to be stored
+ *  \param[in]  CurrentParameter  Pointer to a Buffer containing a Data Element Sequence of UUID elements
+ *
+ *  \return Total number of UUIDs stored in the Data Element Sequence
+ */
+static uint8_t SDP_GetUUIDList(uint8_t UUIDList[][UUID_SIZE_BYTES], const void** const CurrentParameter)
 {
        uint8_t ElementHeaderSize;
        uint8_t TotalUUIDs = 0;
 
 {
        uint8_t ElementHeaderSize;
        uint8_t TotalUUIDs = 0;
 
-       uint16_t ServicePatternLength = ServiceDiscovery_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
+       /* Retrieve the total size of the UUID container, and unwrap the outer Data Element Sequence container */
+       uint16_t ServicePatternLength = SDP_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
        BT_SDP_DEBUG(2, "-- Total UUID Length: 0x%04X", ServicePatternLength);
        while (ServicePatternLength)
        {
        BT_SDP_DEBUG(2, "-- Total UUID Length: 0x%04X", ServicePatternLength);
        while (ServicePatternLength)
        {
+               /* Retrieve the size of the next UUID in the container and get a pointer to the next free UUID element in the list */
                uint8_t* CurrentUUID = UUIDList[TotalUUIDs++];
                uint8_t* CurrentUUID = UUIDList[TotalUUIDs++];
-               uint8_t  UUIDLength  = ServiceDiscovery_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
+               uint8_t  UUIDLength  = SDP_GetDataElementSize(CurrentParameter, &ElementHeaderSize);
                
                
-               memcpy(CurrentUUID, BaseUUID, sizeof(BaseUUID));
-               memcpy(&CurrentUUID[(UUIDLength <= 4) ? (UUID_SIZE_BYTES - 4) : 0], *CurrentParameter, UUIDLength);
+               /* Copy over UUID from the container to the free slot */
+               if (UUIDLength <= 4)
+               {
+                       /* Copy over the base UUID value to the free UUID slot in the list */
+                       memcpy_P(CurrentUUID, &BaseUUID, sizeof(BaseUUID));
+
+                       /* Copy over short UUID */
+                       memcpy(CurrentUUID + (4 - UUIDLength), *CurrentParameter, UUIDLength);
+               }
+               else
+               {
+                       /* Copy over full UUID */
+                       memcpy(CurrentUUID, *CurrentParameter, UUIDLength);             
+               }
                
                
-               BT_SDP_DEBUG(2, "-- UUID (%d): 0x%02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
+               BT_SDP_DEBUG(2, "-- UUID (%d): %02X%02X%02X%02X-%02X%02X-%02X%02X-%02X%02X-%02X%02X%02X%02X%02X%02X",
                                UUIDLength,
                                UUIDLength,
-                               CurrentUUID[15], CurrentUUID[14], CurrentUUID[13], CurrentUUID[12],
-                               CurrentUUID[11], CurrentUUID[10], CurrentUUID[9],  CurrentUUID[8],
-                               CurrentUUID[7],  CurrentUUID[6],  CurrentUUID[5],  CurrentUUID[4],
-                               CurrentUUID[3],  CurrentUUID[2],  CurrentUUID[1],  CurrentUUID[0]);
+                               CurrentUUID[0], CurrentUUID[1], CurrentUUID[2], CurrentUUID[3],
+                               CurrentUUID[4], CurrentUUID[5],
+                                               CurrentUUID[6], CurrentUUID[7],
+                               CurrentUUID[8], CurrentUUID[9],
+                                               CurrentUUID[10], CurrentUUID[11], CurrentUUID[12],  CurrentUUID[13],  CurrentUUID[14],  CurrentUUID[15]);
 
                ServicePatternLength -= (UUIDLength + ElementHeaderSize);
                *CurrentParameter    += UUIDLength;
 
                ServicePatternLength -= (UUIDLength + ElementHeaderSize);
                *CurrentParameter    += UUIDLength;
@@ -232,37 +629,79 @@ static uint8_t ServiceDiscovery_GetUUIDList(uint8_t UUIDList[][UUID_SIZE_BYTES],
        return TotalUUIDs;
 }
 
        return TotalUUIDs;
 }
 
-static uint32_t ServiceDiscovery_GetDataElementSize(const void** DataElementHeader, uint8_t* ElementHeaderSize)
+/** Retrieves the total size of the given locally stored (in PROGMEM) attribute Data Element container.
+ *
+ *  \param[in]  AttributeData  Pointer to the start of the Attribute container, located in PROGMEM
+ *  \param[out] HeaderSize     Pointer to a location where the header size of the data element is to be stored
+ *
+ *  \return Size in bytes of the entire attribute container, including the header
+ */
+static uint32_t SDP_GetLocalAttributeContainerSize(const void* const AttributeData, uint8_t* const HeaderSize)
 {
 {
-       /* Fetch the size of the Data Element structure from the header, increment the current buffer pos */
-       uint8_t SizeIndex = (*((uint8_t*)*DataElementHeader) & 0x07);
-       *DataElementHeader += sizeof(uint8_t);
+       /* Fetch the size of the Data Element structure from the header */
+       uint8_t SizeIndex = (pgm_read_byte(AttributeData) & 0x07);
        
        
-       uint32_t ElementValue;
+       uint32_t ElementValueSize;
+
+       /* Convert the Data Element size index into a size in bytes */
+       switch (SizeIndex)
+       {
+               case SDP_DATASIZE_Variable8Bit:
+                       *HeaderSize = (1 + sizeof(uint8_t));
+                       ElementValueSize = pgm_read_byte(AttributeData + 1);
+                       break;
+               case SDP_DATASIZE_Variable16Bit:
+                       *HeaderSize = (1 + sizeof(uint16_t));
+                       ElementValueSize = SwapEndian_16(pgm_read_word(AttributeData + 1));
+                       break;
+               case SDP_DATASIZE_Variable32Bit:
+                       *HeaderSize = (1 + sizeof(uint32_t));
+                       ElementValueSize = SwapEndian_32(pgm_read_dword(AttributeData + 1));
+                       break;
+               default:
+                       *HeaderSize = 1;
+                       ElementValueSize = (1 << SizeIndex);
+                       break;
+       }
+
+       return ElementValueSize;
+}
+
+/** Retrieves the size of a Data Element container from the current input buffer, and advances the input buffer
+ *  pointer to the start of the Data Element's contents.
+ *
+ *  \param[in, out] DataElementHeader  Pointer to the start of a Data Element header
+ *  \param[out]     ElementHeaderSize  Size in bytes of the header that was skipped
+ *
+ *  \return Size in bytes of the Data Element container's contents, minus the header
+ */
+static uint32_t SDP_GetDataElementSize(const void** const DataElementHeader, uint8_t* const ElementHeaderSize)
+{
+       /* Fetch the size of the Data Element structure from the header, increment the current buffer pos */
+       uint8_t  SizeIndex = (SDP_ReadData8(DataElementHeader) & 0x07); 
+
+       uint32_t ElementValueSize;
 
        /* Convert the Data Element size index into a size in bytes */
        switch (SizeIndex)
        {
 
        /* Convert the Data Element size index into a size in bytes */
        switch (SizeIndex)
        {
-               case 5:
-                       ElementValue = *((uint8_t*)*DataElementHeader);
-                       *DataElementHeader += sizeof(uint8_t);
+               case SDP_DATASIZE_Variable8Bit:
                        *ElementHeaderSize  = (1 + sizeof(uint8_t));
                        *ElementHeaderSize  = (1 + sizeof(uint8_t));
+                       ElementValueSize    = SDP_ReadData8(DataElementHeader);
                        break;
                        break;
-               case 6:
-                       ElementValue = *((uint16_t*)*DataElementHeader);
-                       *DataElementHeader += sizeof(uint16_t);
+               case SDP_DATASIZE_Variable16Bit:
                        *ElementHeaderSize  = (1 + sizeof(uint16_t));
                        *ElementHeaderSize  = (1 + sizeof(uint16_t));
+                       ElementValueSize    = SDP_ReadData16(DataElementHeader);
                        break;
                        break;
-               case 7:
-                       ElementValue = *((uint32_t*)*DataElementHeader);
-                       *DataElementHeader += sizeof(uint32_t);
+               case SDP_DATASIZE_Variable32Bit:
                        *ElementHeaderSize  = (1 + sizeof(uint32_t));
                        *ElementHeaderSize  = (1 + sizeof(uint32_t));
+                       ElementValueSize    = SDP_ReadData32(DataElementHeader);
                        break;
                default:
                        break;
                default:
-                       ElementValue = (1 << SizeIndex);
-                       *ElementHeaderSize = 1;
+                       *ElementHeaderSize  = 1;
+                       ElementValueSize    = (1 << SizeIndex);
                        break;
        }
        
                        break;
        }
        
-       return ElementValue;
+       return ElementValueSize;
 }
 }