juce/source/src/core/juce_Uuid.cpp

   1 /*
   2   ==============================================================================
   3
   4    This file is part of the JUCE library - "Jules' Utility Class Extensions"
   5    Copyright 2004-11 by Raw Material Software Ltd.
   6
   7   ------------------------------------------------------------------------------
   8
   9    JUCE can be redistributed and/or modified under the terms of the GNU General
  10    Public License (Version 2), as published by the Free Software Foundation.
  11    A copy of the license is included in the JUCE distribution, or can be found
  12    online at www.gnu.org/licenses.
  13
  14    JUCE is distributed in the hope that it will be useful, but WITHOUT ANY
  15    WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
  16    A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
  17
  18   ------------------------------------------------------------------------------
  19
  20    To release a closed-source product which uses JUCE, commercial licenses are
  21    available: visit www.rawmaterialsoftware.com/juce for more information.
  22
  23   ==============================================================================
  24 */
  25
  26 #include "juce_StandardHeader.h"
  27
  28 BEGIN_JUCE_NAMESPACE
  29
  30 #include "juce_Uuid.h"
  31 #include "../maths/juce_Random.h"
  32 #include "juce_Time.h"
  33 #include "../io/network/juce_MACAddress.h"
  34 #include "../memory/juce_MemoryBlock.h"
  35
  36
  37 //==============================================================================
  38 Uuid::Uuid()
  39 {
  40     // Mix up any available MAC addresses with some time-based pseudo-random numbers
  41     // to make it very very unlikely that two UUIDs will ever be the same..
  42
  43     static int64 macAddresses[2];
  44     static bool hasCheckedMacAddresses = false;
  45
  46     if (! hasCheckedMacAddresses)
  47     {
  48         hasCheckedMacAddresses = true;
  49
  50         Array<MACAddress> result;
  51         MACAddress::findAllAddresses (result);
  52
  53         for (int i = 0; i < numElementsInArray (macAddresses); ++i)
  54             macAddresses[i] = result[i].toInt64();
  55     }
  56
  57     value.asInt64[0] = macAddresses[0];
  58     value.asInt64[1] = macAddresses[1];
  59
  60     // We'll use both a local RNG that is re-seeded, plus the shared RNG,
  61     // whose seed will carry over between calls to this method.
  62
  63     Random r (macAddresses[0] ^ macAddresses[1]
  64                 ^ Random::getSystemRandom().nextInt64());
  65
  66     for (int i = 4; --i >= 0;)
  67     {
  68         r.setSeedRandomly(); // calling this repeatedly improves randomness
  69         value.asInt[i] ^= r.nextInt();
  70         value.asInt[i] ^= Random::getSystemRandom().nextInt();
  71     }
  72 }
  73
  74 Uuid::~Uuid() noexcept
  75 {
  76 }
  77
  78 Uuid::Uuid (const Uuid& other)
  79     : value (other.value)
  80 {
  81 }
  82
  83 Uuid& Uuid::operator= (const Uuid& other)
  84 {
  85     value = other.value;
  86     return *this;
  87 }
  88
  89 bool Uuid::operator== (const Uuid& other) const
  90 {
  91     return value.asInt64[0] == other.value.asInt64[0]
  92         && value.asInt64[1] == other.value.asInt64[1];
  93 }
  94
  95 bool Uuid::operator!= (const Uuid& other) const
  96 {
  97     return ! operator== (other);
  98 }
  99
 100 bool Uuid::isNull() const noexcept
 101 {
 102     return (value.asInt64 [0] == 0) && (value.asInt64 [1] == 0);
 103 }
 104
 105 //==============================================================================
 106 String Uuid::toString() const
 107 {
 108     return String::toHexString (value.asBytes, sizeof (value.asBytes), 0);
 109 }
 110
 111 Uuid::Uuid (const String& uuidString)
 112 {
 113     operator= (uuidString);
 114 }
 115
 116 Uuid& Uuid::operator= (const String& uuidString)
 117 {
 118     MemoryBlock mb;
 119     mb.loadFromHexString (uuidString);
 120     mb.ensureSize (sizeof (value.asBytes), true);
 121     mb.copyTo (value.asBytes, 0, sizeof (value.asBytes));
 122     return *this;
 123 }
 124
 125 //==============================================================================
 126 Uuid::Uuid (const uint8* const rawData)
 127 {
 128     operator= (rawData);
 129 }
 130
 131 Uuid& Uuid::operator= (const uint8* const rawData)
 132 {
 133     if (rawData != nullptr)
 134         memcpy (value.asBytes, rawData, sizeof (value.asBytes));
 135     else
 136         zeromem (value.asBytes, sizeof (value.asBytes));
 137
 138     return *this;
 139 }
 140
 141
 142 END_JUCE_NAMESPACE