fractal/util.c

/*
 * fractal
 * Written in 2020 by Lucas
 * CC0 1.0 Universal/Public domain - No rights reserved
 *
 * To the extent possible under law, the author(s) have dedicated all
 * copyright and related and neighboring rights to this software to the
 * public domain worldwide. This software is distributed without any
 * warranty. You should have received a copy of the CC0 Public Domain
 * Dedication along with this software. If not, see
 * <http://creativecommons.org/publicdomain/zero/1.0/>.
 */
/* srand48 visibility for GLIBC */
#if !defined(__OpenBSD__)
#define _DEFAULT_SOURCE
#endif

#include <errno.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "util.h"

void
err(int eval, const char *fmt, ...)
{
	va_list ap;
	int saved_errno;

	saved_errno = errno;
	va_start(ap, fmt);
	fprintf(stderr, "%s: ", xgetprogname());
	if (fmt != NULL) {
		vfprintf(stderr, fmt, ap);
		fprintf(stderr, ": ");
	}
	fprintf(stderr, "%s\n", strerror(saved_errno));
	va_end(ap);

	exit(eval);
}

void
errx(int eval, const char *fmt, ...)
{
	va_list ap;

	va_start(ap, fmt);
	if (fmt != NULL) {
		fprintf(stderr, "%s: ", xgetprogname());
		vfprintf(stderr, fmt, ap);
		fprintf(stderr, "\n");
	}
	va_end(ap);

	exit(eval);
}

long double
parse_double(const char *nptr)
{
	char *end;
	long double v;

	errno = 0;
	v = strtold(nptr, &end);
	if (nptr == end || *end != '\0' || (v == 0 && errno == EINVAL))
		errx(1, "invalid number: %s", nptr);
	if (errno == ERANGE)
		errx(1, "number out of range: %s", nptr);

	return v;
}

long long
parse_integer(const char *nptr, long long minval, long long maxval)
{
	char *end;
	long long v;

	errno = 0;
	v = strtoll(nptr, &end, 10);
	if (nptr == end || *end != '\0' || (v == 0 && errno == EINVAL))
		errx(1, "invalid number: %s", nptr);
	if (v == 0 && errno == ERANGE)
		errx(1, "number out of range: %s", nptr);
	if (v < minval)
		errx(1, "number too low: %s", nptr);
	if (v > maxval)
		errx(1, "number too high: %s", nptr);

	return v;
}

const char *
xgetprogname(void)
{
#if defined(__OpenBSD__)
	return getprogname();
#else
	extern char *__progname;
	return __progname;
#endif
}

void
xsrand48(long seed)
{
#if defined(__OpenBSD__)
	srand48_deterministic(seed);
#else
	srand48(seed);
#endif
}