/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2001 Brian Somers <brian@Awfulhak.org>
* Based on original work by Atsushi Murai <amurai@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*/
#include <sys/cdefs.h>
#include <sys/param.h>
#include <libutil.h>
#include <string.h>
#include <unistd.h>
static int isDISP(const char *);
/*-
* Trim the current domain name from fullhost, but only if the result
* is less than or equal to hostsize in length.
*
* This function understands $DISPLAY type fullhosts.
*
* For example:
*
* trimdomain("abcde.my.domain", 5) -> "abcde"
* trimdomain("abcde.my.domain", 4) -> "abcde.my.domain"
* trimdomain("abcde.my.domain:0.0", 9) -> "abcde:0.0"
* trimdomain("abcde.my.domain:0.0", 8) -> "abcde.my.domain:0.0"
*/
void
trimdomain(char *fullhost, int hostsize)
{
static size_t dlen;
static int first = 1;
static char domain[MAXHOSTNAMELEN];
char *end, *s;
size_t len;
if (first) {
/* XXX: Should we assume that our domain is this persistent ? */
first = 0;
if (gethostname(domain, sizeof(domain) - 1) == 0 &&
(s = strchr(domain, '.')) != NULL)
memmove(domain, s + 1, strlen(s + 1) + 1);
else
domain[0] = '\0';
dlen = strlen(domain);
}
if (domain[0] == '\0')
return;
s = fullhost;
end = s + hostsize + 1;
if ((s = memchr(s, '.', (size_t)(end - s))) != NULL) {
if (strncasecmp(s + 1, domain, dlen) == 0) {
if (s[dlen + 1] == '\0') {
/* Found -- lose the domain. */
*s = '\0';
} else if (s[dlen + 1] == ':' &&
isDISP(s + dlen + 2) &&
(len = strlen(s + dlen + 1)) < (size_t)(end - s)) {
/* Found -- shuffle the DISPLAY back. */
memmove(s, s + dlen + 1, len + 1);
}
}
}
}
/*
* Is the given string NN or NN.NN where ``NN'' is an all-numeric string ?
*/
static int
isDISP(const char *disp)
{
size_t w;
int res;
w = strspn(disp, "0123456789");
res = 0;
if (w > 0) {
if (disp[w] == '\0')
res = 1; /* NN */
else if (disp[w] == '.') {
disp += w + 1;
w = strspn(disp, "0123456789");
if (w > 0 && disp[w] == '\0')
res = 1; /* NN.NN */
}
}
return (res);
}
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