Added libstack files

stack.c

@@ -0,0 +1,62 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <stdbool.h>
+
+#include "stack.h"
+
+struct Stack {
+	void** data;
+	int top_index;
+	int capacity;
+	int curr_size;
+};
+
+Stack* new_stack(int stack_size) {
+	assert(stack_size > 0);
+	Stack* my_stack = malloc(sizeof(Stack));
+	my_stack->capacity = stack_size;
+	my_stack->data = malloc(stack_size);
+	my_stack->top_index = 0;
+	my_stack->curr_size = 0;
+	return my_stack;
+}
+
+void stack_push(Stack* stack,void* element) {
+	if (stack->curr_size >= stack->capacity-1) {
+		stack->data = realloc(stack->data, stack->capacity*2);
+		stack->capacity *= 2;
+	}
+	*(stack->data + stack->top_index) = element;
+	stack->top_index++;
+	stack->curr_size++;
+	return;
+}
+
+void* stack_pop(Stack* stack) {
+	assert( !(stack_isEmpty(stack)) );
+	free(stack->data + stack->top_index);
+	stack->top_index--;
+	void* to_return = *(stack->data + stack->top_index);
+	*(stack->data + stack->top_index) = NULL;
+
+	stack->curr_size--;
+
+	return to_return;
+}
+
+void* stack_peek(Stack* stack) {
+	void* to_return = *(stack->data + stack->top_index - 1);
+	return to_return;
+}
+
+int stack_size(Stack* stack) {
+	return (stack->curr_size);
+}
+
+bool stack_isEmpty(Stack* stack) {
+	if (stack_size(stack) == 0) {
+		return true;
+	}
+	return false;
+}

stack.h

@@ -0,0 +1,11 @@
+#include <stdbool.h>
+
+typedef struct Stack Stack;
+
+Stack* new_stack(int stack_size);
+
+void stack_push(Stack* stack, void* element);
+void* stack_pop(Stack* stack);
+void* stack_peek(Stack* stack);
+int stack_size(Stack* stack);
+bool stack_isEmpty(Stack* stack);