Use a bitmask instead of an array of bools in the SDP UUID List matching algorithm...

diff --git a/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.c b/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.c
index 0daf8e2..d012251 100644 (file)
--- a/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.c
+++ b/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.c
@@ -458,27 +458,20 @@ static void* SDP_GetAttributeValue(const ServiceAttributeTable_t* AttributeTable
 static bool SDP_SearchServiceTable(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs,
                                               const ServiceAttributeTable_t* CurrAttributeTable)
 {
-       bool UUIDMatch[TotalUUIDs];     
-       
-       /* Set all the match flags to false (not matched) before starting the search */
-       memset(UUIDMatch, false, sizeof(UUIDMatch));
-
        const void* CurrAttribute;
+       uint16_t    UUIDMatchFlags = 0;
        
        /* 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);
+               SDP_CheckUUIDMatch(UUIDList, TotalUUIDs, &UUIDMatchFlags, 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++;
-       }
+       uint8_t UUIDMatches;
+       for (UUIDMatches = 0; UUIDMatchFlags; UUIDMatches++)
+         UUIDMatchFlags &= (UUIDMatchFlags - 1);
        
        /* If all UUIDs have been matched to the current service, return true */
        return (UUIDMatches == TotalUUIDs);
@@ -494,7 +487,7 @@ static bool SDP_SearchServiceTable(uint8_t UUIDList[][UUID_SIZE_BYTES], const ui
  *
  *  \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[],
+static void SDP_CheckUUIDMatch(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs, uint16_t* UUIDMatchFlags,
                                const void* CurrAttribute)
 {
        uint8_t CurrAttributeType = (pgm_read_byte(CurrAttribute) & ~0x07);
@@ -502,16 +495,20 @@ static void SDP_CheckUUIDMatch(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_
        /* Check the data type of the current attribute value - if UUID, compare, if Sequence, unwrap and recurse */
        if (CurrAttributeType == SDP_DATATYPE_UUID)
        {
+               uint16_t CurrUUIDMatchMask = (1 << 0);
+       
                /* Look for matches in the UUID list against the current attribute UUID value */
                for (uint8_t i = 0; i < TotalUUIDs; i++)
                {
                        /* Check if the current unmatched UUID is identical to the search UUID */
-                       if (!(UUIDMatch[i]) && !(memcmp_P(UUIDList[i], (CurrAttribute + 1), UUID_SIZE_BYTES)))
+                       if (!(*UUIDMatchFlags & CurrUUIDMatchMask) && !(memcmp_P(UUIDList[i], (CurrAttribute + 1), UUID_SIZE_BYTES)))
                        {
                                /* Indicate match found for the current attribute UUID and early-abort */
-                               UUIDMatch[i] = true;
+                               *UUIDMatchFlags |= CurrUUIDMatchMask;
                                break;
                        }
+                       
+                       CurrUUIDMatchMask <<= 1;
                }
        }
        else if (CurrAttributeType == SDP_DATATYPE_Sequence)
@@ -527,8 +524,10 @@ static void SDP_CheckUUIDMatch(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_
                        uint8_t  InnerHeaderSize;
                        uint16_t InnerSize = SDP_GetLocalAttributeContainerSize(CurrAttribute, &InnerHeaderSize);
                        
-                       SDP_CheckUUIDMatch(UUIDList, TotalUUIDs, UUIDMatch, CurrAttribute);
-                                               
+                       /* Recursively search of the next element in the sequence, trying to match UUIDs with the UUID list */
+                       SDP_CheckUUIDMatch(UUIDList, TotalUUIDs, UUIDMatchFlags, CurrAttribute);
+
+                       /* Skip to the next element in the sequence */
                        SequenceSize  -= InnerHeaderSize + InnerSize;
                        CurrAttribute += InnerHeaderSize + InnerSize;
                }

diff --git a/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.h b/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.h
index c524775..e7d02b0 100644 (file)
--- a/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.h
+++ b/Demos/Host/Incomplete/BluetoothHost/Lib/SDP.h
@@ -218,7 +218,7 @@
 
                        static bool     SDP_SearchServiceTable(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs,
                                                               const ServiceAttributeTable_t* CurrAttributeTable);
-                       static void     SDP_CheckUUIDMatch(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs, bool UUIDMatch[],
+                       static void     SDP_CheckUUIDMatch(uint8_t UUIDList[][UUID_SIZE_BYTES], const uint8_t TotalUUIDs, uint16_t* UUIDMatchFlags,
                                                           const void* CurrAttribute);
 
                        static uint8_t  SDP_GetAttributeList(uint16_t AttributeList[][2], const void** const CurrentParameter);