JUCE/modules/juce_core/misc/juce_Uuid.cpp

/*
  ==============================================================================

   This file is part of the JUCE library - "Jules' Utility Class Extensions"
   Copyright 2004-11 by Raw Material Software Ltd.

  ------------------------------------------------------------------------------

   JUCE can be redistributed and/or modified under the terms of the GNU General
   Public License (Version 2), as published by the Free Software Foundation.
   A copy of the license is included in the JUCE distribution, or can be found
   online at www.gnu.org/licenses.

   JUCE is distributed in the hope that it will be useful, but WITHOUT ANY
   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
   A PARTICULAR PURPOSE.  See the GNU General Public License for more details.

  ------------------------------------------------------------------------------

   To release a closed-source product which uses JUCE, commercial licenses are
   available: visit www.rawmaterialsoftware.com/juce for more information.

  ==============================================================================
*/

namespace
{
    int64 getRandomSeedFromMACAddresses()
    {
        Array<MACAddress> result;
        MACAddress::findAllAddresses (result);

        Random r;
        for (int i = 0; i < result.size(); ++i)
            r.combineSeed (result[i].toInt64());

        return r.nextInt64();
    }
}

//==============================================================================
Uuid::Uuid()
{
    // The normal random seeding is pretty good, but we'll throw some MAC addresses
    // into the mix too, to make it very very unlikely that two UUIDs will ever be the same..

    static Random r1 (getRandomSeedFromMACAddresses());
    Random r2;

    for (size_t i = 0; i < sizeof (uuid); ++i)
        uuid[i] = (uint8) (r1.nextInt() ^ r2.nextInt());
}

Uuid::~Uuid() noexcept {}

Uuid::Uuid (const Uuid& other) noexcept
{
    memcpy (uuid, other.uuid, sizeof (uuid));
}

Uuid& Uuid::operator= (const Uuid& other) noexcept
{
    memcpy (uuid, other.uuid, sizeof (uuid));
    return *this;
}

bool Uuid::operator== (const Uuid& other) const noexcept    { return memcmp (uuid, other.uuid, sizeof (uuid)) == 0; }
bool Uuid::operator!= (const Uuid& other) const noexcept    { return ! operator== (other); }

bool Uuid::isNull() const noexcept
{
    for (size_t i = 0; i < sizeof (uuid); ++i)
        if (uuid[i] != 0)
            return false;

    return true;
}

String Uuid::toString() const
{
    return String::toHexString (uuid, sizeof (uuid), 0);
}

Uuid::Uuid (const String& uuidString)
{
    operator= (uuidString);
}

Uuid& Uuid::operator= (const String& uuidString)
{
    MemoryBlock mb;
    mb.loadFromHexString (uuidString);
    mb.ensureSize (sizeof (uuid), true);
    mb.copyTo (uuid, 0, sizeof (uuid));
    return *this;
}

Uuid::Uuid (const uint8* const rawData)
{
    operator= (rawData);
}

Uuid& Uuid::operator= (const uint8* const rawData) noexcept
{
    if (rawData != nullptr)
        memcpy (uuid, rawData, sizeof (uuid));
    else
        zeromem (uuid, sizeof (uuid));

    return *this;
}