/* -*- Mode: C; tab-width: 4; indent-tabs-mode: t; c-basic-offset: 4 -*- */
/* NetworkManager -- Network link manager
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA 02110-1301 USA.
 *
 * (C) Copyright 2016 Red Hat, Inc.
 */

#include "nm-default.h"

#include "nm-shared-utils.h"

#include <errno.h>

/*****************************************************************************/

/* _nm_utils_ascii_str_to_int64:
 *
 * A wrapper for g_ascii_strtoll, that checks whether the whole string
 * can be successfully converted to a number and is within a given
 * range. On any error, @fallback will be returned and %errno will be set
 * to a non-zero value. On success, %errno will be set to zero, check %errno
 * for errors. Any trailing or leading (ascii) white space is ignored and the
 * functions is locale independent.
 *
 * The function is guaranteed to return a value between @min and @max
 * (inclusive) or @fallback. Also, the parsing is rather strict, it does
 * not allow for any unrecognized characters, except leading and trailing
 * white space.
 **/
gint64
_nm_utils_ascii_str_to_int64 (const char *str, guint base, gint64 min, gint64 max, gint64 fallback)
{
	gint64 v;
	size_t len;
	char buf[64], *s, *str_free = NULL;

	if (str) {
		while (g_ascii_isspace (str[0]))
			str++;
	}
	if (!str || !str[0]) {
		errno = EINVAL;
		return fallback;
	}

	len = strlen (str);
	if (g_ascii_isspace (str[--len])) {
		/* backward search the first non-ws character.
		 * We already know that str[0] is non-ws. */
		while (g_ascii_isspace (str[--len]))
			;

		/* str[len] is now the last non-ws character... */
		len++;

		if (len >= sizeof (buf))
			s = str_free = g_malloc (len + 1);
		else
			s = buf;

		memcpy (s, str, len);
		s[len] = 0;

		nm_assert (len > 0 && len < strlen (str) && len == strlen (s));
		nm_assert (!g_ascii_isspace (str[len-1]) && g_ascii_isspace (str[len]));
		nm_assert (strncmp (str, s, len) == 0);

		str = s;
	}

	errno = 0;
	v = g_ascii_strtoll (str, &s, base);

	if (errno != 0)
		v = fallback;
	else if (s[0] != 0) {
		errno = EINVAL;
		v = fallback;
	} else if (v > max || v < min) {
		errno = ERANGE;
		v = fallback;
	}

	if (G_UNLIKELY (str_free))
		g_free (str_free);
	return v;
}

/*****************************************************************************/