c small utility functions

parray.c

#include <stdint.h>
#include <inttypes.h>
#include <stdlib.h>
#include <stdio.h>

/*
 * generic array print function.
 *
 * prints array p with len elements of each width size.
 * needs provided function f which should return a string representation of an
 * element if called with a maximum size for the provided buffer and the
 * buffer to write to itself.
 */
void parray(void *p, uint8_t width, size_t len, char *f(void *, size_t, char *))
{
	char buf[10];
	for (size_t i = 0; i < len; i++)
	{
		printf("%c%s%c",
				(i==0) ? '[' : ' ',
				f((p+(i*width)), 10, buf),
				(i+1 >= len) ? ']' : ',');
	}
	printf("\n");
}

char *pr_uint32_t(void *x, size_t n, char buf[n])
{
	snprintf(buf, n, "%" PRIu32, *(uint32_t *)(x));
	return buf;
}

int main()
{
	uint32_t data[] = { 2, 4, 1, 9, 0, 32 };
	parray(data, sizeof data[0], sizeof data / sizeof data[0], pr_uint32_t);

}