Add initial stack implementation

tests/stack/stack_test.c

@@ -0,0 +1,41 @@
+#include "stack.h"
+
+#include <assert.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#define STACK_SIZE 64
+
+STACK_DEFINE(coolstack, STACK_SIZE)
+
+void test_stack(void)
+{
+    int int_arr[STACK_SIZE];
+
+    for(int i = 0; i < STACK_SIZE; i++)
+    {
+        int_arr[i] = i;
+    }
+
+    for(int i = 0; i < STACK_SIZE; i++)
+    {
+        stack_push(&coolstack, &int_arr[i]);
+    }
+
+    for(int i = STACK_SIZE - 1; i >= 0; i--)
+    {
+        assert(*(int*)stack_pop(&coolstack) == i);
+    }
+}
+
+int main(void)
+{
+    printf("Testing Stack.\n");
+    test_stack();
+
+    printf("-------------------------------------------------------------------------------\n");
+    printf("Stack Tests Passed :)\n");
+    printf("-------------------------------------------------------------------------------\n");
+
+    return 0;
+}