reactphysics3d/src/containers/Stack.h
2017-01-08 19:56:59 +01:00

126 lines
4.4 KiB
C++

/********************************************************************************
* ReactPhysics3D physics library, http://www.reactphysics3d.com *
* Copyright (c) 2010-2016 Daniel Chappuis *
*********************************************************************************
* *
* This software is provided 'as-is', without any express or implied warranty. *
* In no event will the authors be held liable for any damages arising from the *
* use of this software. *
* *
* Permission is granted to anyone to use this software for any purpose, *
* including commercial applications, and to alter it and redistribute it *
* freely, subject to the following restrictions: *
* *
* 1. The origin of this software must not be misrepresented; you must not claim *
* that you wrote the original software. If you use this software in a *
* product, an acknowledgment in the product documentation would be *
* appreciated but is not required. *
* *
* 2. Altered source versions must be plainly marked as such, and must not be *
* misrepresented as being the original software. *
* *
* 3. This notice may not be removed or altered from any source distribution. *
* *
********************************************************************************/
#ifndef REACTPHYSICS3D_STACK_H
#define REACTPHYSICS3D_STACK_H
// Libraries
#include "configuration.h"
namespace reactphysics3d {
// Class Stack
/**
* This class represents a simple generic stack with an initial capacity. If the number
* of elements exceeds the capacity, the heap will be used to allocated more memory.
*/
template<typename T, uint capacity>
class Stack {
private:
// -------------------- Attributes -------------------- //
/// Initial array that contains the elements of the stack
T mInitArray[capacity];
/// Pointer to the first element of the stack
T* mElements;
/// Number of elements in the stack
uint mNbElements;
/// Number of allocated elements in the stack
uint mNbAllocatedElements;
public:
// -------------------- Methods -------------------- //
/// Constructor
Stack() : mElements(mInitArray), mNbElements(0), mNbAllocatedElements(capacity) {
}
/// Destructor
~Stack() {
// If elements have been allocated on the heap
if (mInitArray != mElements) {
// Release the memory allocated on the heap
free(mElements);
}
}
/// Push an element into the stack
void push(const T& element);
/// Pop an element from the stack (remove it from the stack and return it)
T pop();
/// Return the number of elments in the stack
uint getNbElements() const;
};
// Push an element into the stack
template<typename T, uint capacity>
inline void Stack<T, capacity>::push(const T& element) {
// If we need to allocate more elements
if (mNbElements == mNbAllocatedElements) {
T* oldElements = mElements;
mNbAllocatedElements *= 2;
mElements = (T*) malloc(mNbAllocatedElements * sizeof(T));
assert(mElements);
memcpy(mElements, oldElements, mNbElements * sizeof(T));
if (oldElements != mInitArray) {
free(oldElements);
}
}
mElements[mNbElements] = element;
mNbElements++;
}
// Pop an element from the stack (remove it from the stack and return it)
template<typename T, uint capacity>
inline T Stack<T, capacity>::pop() {
assert(mNbElements > 0);
mNbElements--;
return mElements[mNbElements];
}
// Return the number of elments in the stack
template<typename T, uint capacity>
inline uint Stack<T, capacity>::getNbElements() const {
return mNbElements;
}
}
#endif