uuid.cpp

Go to the documentation of this file.
00001 /*
00002  * uuid.cpp
00003  *
00004  * Copyright (C) 2010  Thomas A. Vaughan
00005  * All rights reserved.
00006  *
00007  *
00008  * Redistribution and use in source and binary forms, with or without
00009  * modification, are permitted provided that the following conditions are met:
00010  *     * Redistributions of source code must retain the above copyright
00011  *       notice, this list of conditions and the following disclaimer.
00012  *     * Redistributions in binary form must reproduce the above copyright
00013  *       notice, this list of conditions and the following disclaimer in the
00014  *       documentation and/or other materials provided with the distribution.
00015  *     * Neither the name of the <organization> nor the
00016  *       names of its contributors may be used to endorse or promote products
00017  *       derived from this software without specific prior written permission.
00018  *
00019  * THIS SOFTWARE IS PROVIDED BY THOMAS A. VAUGHAN ''AS IS'' AND ANY
00020  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
00021  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
00022  * DISCLAIMED. IN NO EVENT SHALL THOMAS A. VAUGHAN BE LIABLE FOR ANY
00023  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
00024  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
00025  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
00026  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
00027  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
00028  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
00029  *
00030  *
00031  */
00032 
00033 // includes --------------------------------------------------------------------
00034 #include <unistd.h>
00035 
00036 #include "uuid.h"               // always include our own header first!
00037 
00038 
00039 
00040 ////////////////////////////////////////////////////////////////////////////////
00041 //
00042 //      static helper methods
00043 //
00044 ////////////////////////////////////////////////////////////////////////////////
00045 
00046 static word_t
00047 getr4
00048 (
00049 void
00050 )
00051 throw()
00052 {
00053         static bool initRandom = false;
00054         if (!initRandom) {
00055                 DPRINTF("TODO: link to proper UUID generation libraries!");
00056                 srand(time(NULL) + 7 * getpid());
00057                 initRandom = true;
00058         }
00059 
00060         // return 2-byte (4 hex character) random number
00061         return (rand() % 0x10000);
00062 }
00063 
00064 
00065 
00066 ////////////////////////////////////////////////////////////////////////////////
00067 //
00068 //      public API
00069 //
00070 ////////////////////////////////////////////////////////////////////////////////
00071 
00072 const char *
00073 generateUUID
00074 (
00075 OUT char * buffer
00076 )
00077 {
00078         ASSERT(buffer, "null");
00079 
00080         snprintf(buffer, eUUID_Length,
00081             "%04x%04x-%04x-%04x-%04x-%04x%08x",
00082             getr4(), getr4(), getr4(), getr4(), getr4(),
00083             (word_t) getpid(), (dword_t) time(NULL));
00084 //      DPRINTF("  uuid: '%s'", buffer);
00085 
00086         return buffer;
00087 }
00088