49 lines
2.7 KiB
C
49 lines
2.7 KiB
C
/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
|
|
│vi: set net ft=c ts=2 sts=2 sw=2 fenc=utf-8 :vi│
|
|
╞══════════════════════════════════════════════════════════════════════════════╡
|
|
│ Copyright 2020 Justine Alexandra Roberts Tunney │
|
|
│ │
|
|
│ Permission to use, copy, modify, and/or distribute this software for │
|
|
│ any purpose with or without fee is hereby granted, provided that the │
|
|
│ above copyright notice and this permission notice appear in all copies. │
|
|
│ │
|
|
│ THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL │
|
|
│ WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED │
|
|
│ WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE │
|
|
│ AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL │
|
|
│ DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR │
|
|
│ PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER │
|
|
│ TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR │
|
|
│ PERFORMANCE OF THIS SOFTWARE. │
|
|
╚─────────────────────────────────────────────────────────────────────────────*/
|
|
#include "libc/alg/alg.h"
|
|
#include "libc/dns/dns.h"
|
|
#include "libc/dns/hoststxt.h"
|
|
|
|
/**
|
|
* Compares hostnames in HOSTS.TXT table.
|
|
* @see dnsnamecmp(), parsehoststxt()
|
|
*/
|
|
static int cmphoststxt(const struct HostsTxtEntry *e1,
|
|
const struct HostsTxtEntry *e2, const char *strings) {
|
|
if (e1 == e2) return 0;
|
|
return dnsnamecmp(&strings[e1->name], &strings[e2->name]);
|
|
}
|
|
|
|
/**
|
|
* Sorts entries in HOSTS.TXT table.
|
|
*
|
|
* This function enables resolvehoststxt() to be called so hard-coded
|
|
* hostname lookups take logarithmic time; you can blackhole all the
|
|
* spam you want, in your /etc/hosts file.
|
|
*
|
|
* The sorted order, defined by dnsnamecmp(), also makes it possible to
|
|
* efficiently search for subdomains, once the initial sort is done.
|
|
*/
|
|
void sorthoststxt(struct HostsTxt *ht) {
|
|
if (ht->entries.p) {
|
|
qsort_r(ht->entries.p, ht->entries.i, sizeof(*ht->entries.p),
|
|
(void *)cmphoststxt, ht->strings.p);
|
|
}
|
|
}
|