UUID.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 
00017 #ifndef __UUID_H__
00018 #define __UUID_H__
00019 
00020 #include <string.h>
00021 
00022 #include "blecommon.h"
00023 
00024 const unsigned   LENGTH_OF_LONG_UUID = 16;
00025 typedef uint16_t ShortUUIDBytes_t;
00026 typedef uint8_t  LongUUIDBytes_t[LENGTH_OF_LONG_UUID];
00027 
00028 class UUID {
00029 public:
00030     enum UUID_Type_t {
00031         UUID_TYPE_SHORT = 0,    // Short BLE UUID
00032         UUID_TYPE_LONG  = 1     // Full 128-bit UUID
00033     };
00034 
00035 public:
00036     /**
00037      * Creates a new 128-bit UUID
00038      *
00039      * @note   The UUID is a unique 128-bit (16 byte) ID used to identify
00040      *         different service or characteristics on the BLE device.
00041      *
00042      * @param longUUID
00043      *          The 128-bit (16-byte) UUID value.
00044      */
00045     UUID(const LongUUIDBytes_t longUUID) : type(UUID_TYPE_LONG), baseUUID(), shortUUID(0) {
00046         memcpy(baseUUID, longUUID, LENGTH_OF_LONG_UUID);
00047         shortUUID = (uint16_t)((longUUID[2] << 8) | (longUUID[3]));
00048     }
00049 
00050     /**
00051      * Creates a new 16-bit UUID
00052      *
00053      * @note The UUID is a unique 16-bit (2 byte) ID used to identify
00054      *       different service or characteristics on the BLE device.
00055      *
00056      * For efficiency, and because 16 bytes would take a large chunk of the
00057      * 27-byte data payload length of the Link Layer, the BLE specification adds
00058      * two additional UUID formats: 16-bit and 32-bit UUIDs. These shortened
00059      * formats can be used only with UUIDs that are defined in the Bluetooth
00060      * specification (i.e., that are listed by the Bluetooth SIG as standard
00061      * Bluetooth UUIDs).
00062      *
00063      * To reconstruct the full 128-bit UUID from the shortened version, insert
00064      * the 16-bit short value (indicated by xxxx, including leading zeros) into
00065      * the Bluetooth Base UUID:
00066      *
00067      *  0000xxxx-0000-1000-8000-00805F9B34FB
00068      *
00069      * @note Shortening is not available for UUIDs that are not derived from the
00070      *       Bluetooth Base UUID. Such non-standard UUIDs are commonly called
00071      *       vendor-specific UUIDs. In these cases, you’ll need to use the full
00072      *       128-bit UUID value at all times.
00073      *
00074      * @note we don't yet support 32-bit shortened UUIDs.
00075      */
00076     UUID(ShortUUIDBytes_t shortUUID) : type(UUID_TYPE_SHORT), baseUUID(), shortUUID(shortUUID) {
00077         /* empty */
00078     }
00079 
00080 public:
00081     UUID_Type_t       shortOrLong(void)  const {return type;     }
00082     const uint8_t    *getBaseUUID(void)  const {
00083         if (type == UUID_TYPE_SHORT) {
00084             return (const uint8_t*)&shortUUID;
00085         } else {
00086             return baseUUID;
00087         }
00088     }
00089 
00090     ShortUUIDBytes_t  getShortUUID(void) const {return shortUUID;}
00091     uint8_t           getLen(void)       const {
00092         return ((type == UUID_TYPE_SHORT) ? sizeof(ShortUUIDBytes_t) : LENGTH_OF_LONG_UUID);
00093     }
00094 
00095     bool operator== (const UUID &other) const {
00096         if ((this->type == UUID_TYPE_SHORT) && (other.type == UUID_TYPE_SHORT) &&
00097             (this->shortUUID == other.shortUUID)) {
00098             return true;
00099         }
00100 
00101         if ((this->type == UUID_TYPE_LONG) && (other.type == UUID_TYPE_LONG) &&
00102             (memcmp(this->baseUUID, other.baseUUID, LENGTH_OF_LONG_UUID) == 0)) {
00103             return true;
00104         }
00105 
00106         return false;
00107     }
00108 
00109 private:
00110     UUID_Type_t      type;      // UUID_TYPE_SHORT or UUID_TYPE_LONG
00111     LongUUIDBytes_t  baseUUID;  /* the base of the long UUID (if
00112                             * used). Note: bytes 12 and 13 (counting from LSB)
00113                             * are zeroed out to allow comparison with other long
00114                             * UUIDs which differ only in the 16-bit relative
00115                             * part.*/
00116     ShortUUIDBytes_t shortUUID; // 16 bit uuid (byte 2-3 using with base)
00117 };
00118 
00119 #endif // ifndef __UUID_H__