ladybird/AK/IDAllocator.h
Andreas Kling 9fd58fd6d8 AK: Use get_random() in IDAllocator
Also generate a new random ID on collision, instead of using
the old ID + 1. :^)

SonarCloud: https://sonarcloud.io/project/security_hotspots?id=SerenityOS_serenity&hotspots=AXuVPBMNk92xXUF3qWZd
2021-08-30 18:35:36 +02:00

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925 B
C++

/*
* Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Forward.h>
#include <AK/HashTable.h>
#include <AK/Random.h>
namespace AK {
// This class manages a pool of random ID's in the range 1..INT32_MAX
class IDAllocator {
public:
IDAllocator() = default;
~IDAllocator() = default;
int allocate()
{
VERIFY(m_allocated_ids.size() < (INT32_MAX - 2));
int id = 0;
for (;;) {
id = static_cast<int>(get_random_uniform(NumericLimits<int>::max()));
if (id == 0)
continue;
if (m_allocated_ids.set(id) == AK::HashSetResult::InsertedNewEntry)
break;
}
return id;
}
void deallocate(int id)
{
m_allocated_ids.remove(id);
}
private:
HashTable<int> m_allocated_ids;
};
}
using AK::IDAllocator;