/* a linked list with custom element types.
   this file can be included multiple times to create differently typed
   versions, depending the value of the preprocessor variables
   mi-list-name-infix and mi-list-element-t before inclusion */
#include <stdlib.h>
#include <inttypes.h>
#ifndef mi_list_name_prefix
#define mi_list_name_prefix mi_list_64
#endif
#ifndef mi_list_element_t
#define mi_list_element_t uint64_t
#endif

/* there does not seem to be a simpler way for identifier concatenation in c in
 * this case */
#ifndef mi_list_name_concat
#define mi_list_name_concat(a, b) a##_##b
#define mi_list_name_concatenator(a, b) mi_list_name_concat(a, b)
#define mi_list_name(name) mi_list_name_concatenator(mi_list_name_prefix, name)
#endif

#define mi_list_struct_name mi_list_name(struct)
#define mi_list_t mi_list_name(t)
typedef struct mi_list_struct_name {
  struct mi_list_struct_name* link;
  mi_list_element_t data;
} mi_list_t;
#ifndef mi_list_first
#define mi_list_first(a) a->data
#define mi_list_first_address(a) &(a->data)
#define mi_list_rest(a) a->link
#endif

/** removes and deallocates the first element */
mi_list_t* mi_list_name(drop)(mi_list_t* a) {
  mi_list_t* a_next = mi_list_rest(a);
  free(a);
  return (a_next);
}

/** it would be nice to set the pointer to zero, but that would require more
 * indirection with a pointer-pointer */
void mi_list_name(destroy)(mi_list_t* a) {
  mi_list_t* a_next = 0;
  while (a) {
    a_next = a->link;
    free(a);
    a = a_next;
  };
}
mi_list_t* mi_list_name(add)(mi_list_t* a, mi_list_element_t value) {
  mi_list_t* element = calloc(1, (sizeof(mi_list_t)));
  if (!element) {
    return (0);
  };
  element->data = value;
  element->link = a;
  return (element);
}
size_t mi_list_name(length)(mi_list_t* a) {
  size_t result = 0;
  while (a) {
    result = (1 + result);
    a = mi_list_rest(a);
  };
  return (result);
}
#undef mi_list_name_prefix
#undef mi_list_element_t
#undef mi_list_struct_name
#undef mi_list_t