Diff: ble/UUID.h

Revision:

1042:21a86ac7f5b1

Parent:

1039:2ea9d52111e2

Child:

1048:efb29faf12fc

--- a/ble/UUID.h	Thu Dec 10 09:15:05 2015 +0000
+++ b/ble/UUID.h	Mon Jan 11 08:51:25 2016 +0000
@@ -19,120 +19,37 @@
 
 #include <stdint.h>
 #include <string.h>
-#include <algorithm>
 
 #include "blecommon.h"
 
-/**
- * A trivial converter for single hexadecimal character to unsigned-int.
- * @param  c hexadecimal character.
- * @return   the corresponding value as unsigned int.
- */
-static uint8_t char2int(char c) {
-    if ((c >= '0') && (c <= '9')) {
-        return c - '0';
-    } else if ((c >= 'a') && (c <= 'f')) {
-        return c - 'a' + 10;
-    } else if ((c >= 'A') && (c <= 'F')) {
-        return c - 'A' + 10;
-    } else {
-        return 0;
-    }
-}
-
 class UUID {
 public:
     enum UUID_Type_t {
-        UUID_TYPE_SHORT = 0,    // Short BLE UUID.
-        UUID_TYPE_LONG  = 1     // Full 128-bit UUID.
+        UUID_TYPE_SHORT = 0,    // Short BLE UUID
+        UUID_TYPE_LONG  = 1     // Full 128-bit UUID
     };
 
-    /**
-     * An enumeration to specify byte ordering of the long version of the UUID.
-     */
-    typedef enum {
-        MSB, /*!< Most-significant byte first (at the smallest address) */
-        LSB  /*!< least-significant byte first (at the smallest address) */
-    } ByteOrder_t;
-
     typedef uint16_t      ShortUUIDBytes_t;
 
     static const unsigned LENGTH_OF_LONG_UUID = 16;
     typedef uint8_t       LongUUIDBytes_t[LENGTH_OF_LONG_UUID];
 
-    static const unsigned MAX_UUID_STRING_LENGTH = LENGTH_OF_LONG_UUID * 2 + 4;
-
 public:
-
     /**
-     * Creates a new 128-bit UUID.
-     *
-     * @note   The UUID is a unique 128-bit (16 byte) ID used to identify
-     *         different service or characteristics on the BLE device.
-     *
-     * @param  stringUUID
-     *          The 128-bit (16-byte) UUID as a human readable const-string.
-     *          Format: XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
-     *          Upper and lower case supported. Hyphens are optional, but only
-     *          upto four of them. The UUID is stored internally as a 16 byte
-     *          array, LSB (little endian), which is opposite from the string.
-     */
-    UUID(const char* stringUUID) : type(UUID_TYPE_LONG), baseUUID(), shortUUID(0) {
-        bool nibble = false;
-        uint8_t byte = 0;
-        size_t baseIndex = 0;
-        uint8_t tempUUID[LENGTH_OF_LONG_UUID];
-
-        // Iterate through string, abort if NULL is encountered prematurely.
-        // Ignore upto four hyphens.
-        for (size_t index = 0; (index < MAX_UUID_STRING_LENGTH) && (baseIndex < LENGTH_OF_LONG_UUID); index++) {
-            if (stringUUID[index] == '\0') {
-                // error abort
-                break;
-            } else if (stringUUID[index] == '-') {
-                // ignore hyphen
-                continue;
-            } else if (nibble) {
-                // got second nibble
-                byte |= char2int(stringUUID[index]);
-                nibble = false;
-
-                // store copy
-                tempUUID[baseIndex++] = byte;
-            } else {
-                // got first nibble
-                byte = char2int(stringUUID[index]) << 4;
-                nibble = true;
-            }
-        }
-
-        // populate internal variables if string was successfully parsed
-        if (baseIndex == LENGTH_OF_LONG_UUID) {
-            setupLong(tempUUID, UUID::MSB);
-        } else {
-            const uint8_t sig[] = { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x10, 0x00,
-                                    0x80, 0x00, 0x00, 0x80, 0x5F, 0x9B, 0x34, 0xFB };
-            setupLong(sig, UUID::MSB);
-        }
-    }
-
-    /**
-     * Creates a new 128-bit UUID.
+     * Creates a new 128-bit UUID
      *
      * @note   The UUID is a unique 128-bit (16 byte) ID used to identify
      *         different service or characteristics on the BLE device.
      *
      * @param longUUID
-     *          The 128-bit (16-byte) UUID value.
-     * @param order
-     *          The bit order of the UUID, MSB by default.
+     *          The 128-bit (16-byte) UUID value, MSB first (big-endian).
      */
-    UUID(const LongUUIDBytes_t longUUID, ByteOrder_t order = UUID::MSB) : type(UUID_TYPE_LONG), baseUUID(), shortUUID(0) {
-        setupLong(longUUID, order);
+    UUID(const LongUUIDBytes_t longUUID) : type(UUID_TYPE_LONG), baseUUID(), shortUUID(0) {
+        setupLong(longUUID);
     }
 
     /**
-     * Creates a new 16-bit UUID.
+     * Creates a new 16-bit UUID
      *
      * @note The UUID is a unique 16-bit (2 byte) ID used to identify
      *       different service or characteristics on the BLE device.
@@ -141,7 +58,7 @@
      * 27-byte data payload length of the Link Layer, the BLE specification adds
      * two additional UUID formats: 16-bit and 32-bit UUIDs. These shortened
      * formats can be used only with UUIDs that are defined in the Bluetooth
-     * specification (listed by the Bluetooth SIG as standard
+     * specification (i.e., that are listed by the Bluetooth SIG as standard
      * Bluetooth UUIDs).
      *
      * To reconstruct the full 128-bit UUID from the shortened version, insert
@@ -155,10 +72,10 @@
      *       vendor-specific UUIDs. In these cases, you’ll need to use the full
      *       128-bit UUID value at all times.
      *
-     * @note We don't yet support 32-bit shortened UUIDs.
+     * @note we don't yet support 32-bit shortened UUIDs.
      */
     UUID(ShortUUIDBytes_t _shortUUID) : type(UUID_TYPE_SHORT), baseUUID(), shortUUID(_shortUUID) {
-        /* Empty */
+        /* empty */
     }
 
     UUID(const UUID &source) {
@@ -172,17 +89,12 @@
     }
 
     /**
-     * Fill in a 128-bit UUID; this is useful when the UUID isn't known at the time of the object construction.
+     * Fill in a 128-bit UUID; this is useful when UUID isn't known at the time of object construction.
      */
-    void setupLong(const LongUUIDBytes_t longUUID, ByteOrder_t order = UUID::MSB) {
+    void setupLong(const LongUUIDBytes_t longUUID) {
         type      = UUID_TYPE_LONG;
-        if (order == UUID::MSB) {
-            // Switch endian. Input is big-endian, internal representation is little endian.
-            std::reverse_copy(longUUID, longUUID + LENGTH_OF_LONG_UUID, baseUUID);
-        } else {
-            std::copy(longUUID, longUUID + LENGTH_OF_LONG_UUID, baseUUID);
-        }
-        shortUUID = (uint16_t)((baseUUID[13] << 8) | (baseUUID[12]));
+        memcpy(baseUUID, longUUID, LENGTH_OF_LONG_UUID);
+        shortUUID = (uint16_t)((longUUID[2] << 8) | (longUUID[3]));
     }
 
 public:
@@ -220,8 +132,12 @@
 
 private:
     UUID_Type_t      type;      // UUID_TYPE_SHORT or UUID_TYPE_LONG
-    LongUUIDBytes_t  baseUUID;  // The long UUID
-    ShortUUIDBytes_t shortUUID; // 16 bit UUID
+    LongUUIDBytes_t  baseUUID;  /* the base of the long UUID (if
+                            * used). Note: bytes 12 and 13 (counting from LSB)
+                            * are zeroed out to allow comparison with other long
+                            * UUIDs which differ only in the 16-bit relative
+                            * part.*/
+    ShortUUIDBytes_t shortUUID; // 16 bit uuid (byte 2-3 using with base)
 };
 
 #endif // ifndef __UUID_H__
\ No newline at end of file