HEADER POUR GERER UNE PILE DYNAMIQUEMENT

/*
 * Create by : deck_bsd
 * Date of creation : 27/05/2006.
 * Task : This header contain the fundamental functions for the to use a stack. (Linux/windows).
 *
 * Remark : The constante T and EMPTY must be defined in a #define before the include of header.
 */
 
 #include <stdbool.h>
 
 typedef struct element{
	 T tElem;
	 struct element * ptNext;
}ELEMENT;
 
 typedef struct stack{
	 ELEMENT * ptTop;
 }STACK;
 
 /*TASK : Create a stack. */
 STACK * dCreateStack(void){
	 STACK * ptPile;
	 
	 ptPile = (STACK*)malloc(sizeof(STACK));
	 if(ptPile == NULL) return NULL;
	
	ptPile->ptTop = NULL;
	
	return ptPile;
 }

/*TASK : Put a element onto the stack. */ 
bool dPush(STACK * ptPile,T ttElem){
	ELEMENT * ptNewElem;
	
	ptNewElem = (ELEMENT*)malloc(sizeof(ELEMENT));
	if(ptNewElem == NULL) return false;
	
	ptNewElem->tElem = ttElem;
	
	ptNewElem->ptNext = ptPile->ptTop;
	ptPile->ptTop = ptNewElem;
	
	return true;
}

/*TASK : Delete the element on the top of stack and return its value. */
T dPop(STACK * ptPile){
	T ttElem;
	ELEMENT *ptDes;
	
	if(ptPile->ptTop == NULL)return EMPTY;
	ptDes = ptPile->ptTop;
	ttElem = ptDes->tElem;
	
	ptPile->ptTop = ptDes->ptNext;
	
	free(ptDes);
	
	return ttElem;
}

/*TASK : return the value of the top. */
T dTop(STACK * ptPile){
	if(ptPile->ptTop != NULL)return ptPile->ptTop->tElem;
	return EMPTY;
}

/*TASK : check the state of the stack. */
bool dIsEmpty(STACK * ptPile){
	if(ptPile->ptTop == NULL)return true;
	return false;
}

/*TASK : destroy the stack. */
void dDestroyStack(STACK * ptPile){
	ELEMENT * ptDes,* ptSave;
	
	if(ptPile->ptTop != NULL){
		ptDes = ptPile->ptTop;
		while(ptDes != NULL){
			ptSave = ptDes->ptNext;
			free(ptDes);
			ptDes = ptSave;
		}
	}
	free(ptPile);
}