order.c File Reference

Functions for finding the n'th element of an array. More...

#include <stdlib.h>
#include "lib/container/order.h"
#include "lib/log/util_bug.h"

Go to the source code of this file.


#define IMPLEMENT_ORDER_FUNC(funcname, elt_t)

Detailed Description

Functions for finding the n'th element of an array.

Definition in file order.c.

Macro Definition Documentation


#define IMPLEMENT_ORDER_FUNC (   funcname,
static int \
_cmp_ ## elt_t(const void *_a, const void *_b) \
{ \
const elt_t *a = _a, *b = _b; \
if (*a<*b) \
return -1; \
else if (*a>*b) \
return 1; \
else \
return 0; \
} \
elt_t \
funcname(elt_t *array, int n_elements, int nth) \
{ \
tor_assert(nth >= 0); \
tor_assert(nth < n_elements); \
qsort(array, n_elements, sizeof(elt_t), _cmp_ ##elt_t); \
return array[nth]; \

Declare a function called funcname that acts as a find_nth_FOO function for an array of type elt_t*.

NOTE: The implementation kind of sucks: It's O(n log n), whereas finding the kth element of an n-element list can be done in O(n). Then again, this implementation is not in critical path, and it is obviously correct.

Definition at line 22 of file order.c.