Turned Scheduler into more generic heap

This commit is contained in:
2021-04-06 14:44:45 -05:00
parent 51b6c13b16
commit 603a1a9dcc
4 changed files with 116 additions and 105 deletions

78
src/heap.cpp Normal file
View File

@@ -0,0 +1,78 @@
#include "heap.hpp"
template<class T>
kernelns::Heap<T>::Heap()
{
}
template<class T>
kernelns::Heap<T>::Heap(T** array, size_t maxSize)
{
m_array = array;
m_size = 0;
m_limit = maxSize;
}
template<class T>
T* kernelns::Heap<T>::extractMin()
{
if(m_size == 0)
return nullptr;
m_size--;
T* p = m_array[0];
m_array[0] = m_array[m_size];
heapify(0);
return p;
}
template<class T>
void kernelns::Heap<T>::insert(T* n)
{
if(m_size == m_limit) // TODO: have insert return status code
return;
size_t i = m_size;
m_size++;
while(i > 0 && *m_array[(i - 1) / 2] > *n)
{
m_array[i] = m_array[(i - 1) / 2];
i = (i - 1) / 2;
}
m_array[i] = n;
}
template<class T>
void kernelns::Heap<T>::remove(T* n)
{
for(size_t i = 0; i < m_size; i++)
{
if(m_array[i] == n)
{
m_size--;
m_array[i] = m_array[m_size];
heapify(i);
break;
}
}
}
template<class T>
void kernelns::Heap<T>::heapify(size_t i)
{
if(i * 2 + 1 >= m_size)
return;
if (*m_array[i * 2 + 1] <= *m_array[i] && *m_array[i * 2 + 1] <= *m_array[i * 2 + 2])
{
T buffer = m_array[i];
m_array[i] = m_array[i * 2 + 1];
m_array[i * 2 + 1] = buffer;
heapify(i * 2 + 1);
}
else if (*m_array[i * 2 + 2] <= *m_array[i] && *m_array[i * 2 + 2] <= *m_array[i * 2 + 1])
{
T buffer = m_array[i];
m_array[i] = m_array[i * 2 + 2];
m_array[i * 2 + 2] = buffer;
heapify(i * 2 + 2);
}
}

38
src/heap.hpp Normal file
View File

@@ -0,0 +1,38 @@
#ifndef SCHEDULER_H
#define SCHEDULER_H
#include <stddef.h>
#include "process.hpp"
namespace kernelns
{
template<class T>
class Heap
{
public:
Heap();
Heap(T** array, size_t maxSize);
T* extractMin();
void insert(T* n);
void remove(T* n);
private:
void heapify(size_t index);
T** m_array;
size_t m_size, m_limit;
};
};
#endif

View File

@@ -1,68 +0,0 @@
#include "scheduler.hpp"
kernelns::ProcessQueue::ProcessQueue()
{
}
kernelns::ProcessQueue::ProcessQueue(Process** array)
{
m_array = array;
m_size = 0;
}
kernelns::Process* kernelns::ProcessQueue::extractMin()
{
if(m_size == 0)
return NULL;
m_size--;
Process* p = m_array[0];
m_array[0] = m_array[m_size];
heapify(0);
return p;
}
void kernelns::ProcessQueue::insert(Process* n)
{
size_t i = m_size;
m_size++;
for(; i > 0 && m_array[(i - 1) / 2]->priority > n->priority; i = (i - 1) / 2)
{
m_array[i] = m_array[(i - 1) / 2];
}
m_array[i] = n;
}
void kernelns::ProcessQueue::remove(Process* n)
{
for(size_t i = 0; i < m_size; i++)
{
if(m_array[i] == n)
{
m_size--;
m_array[i] = m_array[m_size];
heapify(i);
break;
}
}
}
void kernelns::ProcessQueue::heapify(size_t i)
{
if(i * 2 + 1 >= m_size)
return;
if (m_array[i]->priority >= m_array[i * 2 + 1]->priority && m_array[i * 2 + 1]->priority <= m_array[i * 2 + 2]->priority)
{
Process* buffer = m_array[i];
m_array[i] = m_array[i * 2 + 1];
m_array[i * 2 + 1] = buffer;
heapify(i * 2 + 1);
}
else if (m_array[i]->priority >= m_array[i * 2 + 2]->priority && m_array[i * 2 + 2]->priority <= m_array[i * 2 + 1]->priority)
{
Process* buffer = m_array[i];
m_array[i] = m_array[i * 2 + 2];
m_array[i * 2 + 2] = buffer;
heapify(i * 2 + 2);
}
}

View File

@@ -1,37 +0,0 @@
#ifndef SCHEDULER_H
#define SCHEDULER_H
#include <stddef.h>
#include "process.hpp"
namespace kernelns
{
class ProcessQueue
{
public:
ProcessQueue();
ProcessQueue(Process** array);
Process* extractMin();
void insert(Process* n);
void remove(Process* n);
private:
void heapify(size_t index);
Process** m_array;
size_t m_size;
};
};
#endif