cosmopolitan/libc/dns/dnsheader.c
Jōshin e16a7d8f3b
flip et / noet in modelines
`et` means `expandtab`.

```sh
rg 'vi: .* :vi' -l -0 | \
  xargs -0 sed -i '' 's/vi: \(.*\) et\(.*\)  :vi/vi: \1 xoet\2:vi/'
rg 'vi: .*  :vi' -l -0 | \
  xargs -0 sed -i '' 's/vi: \(.*\)noet\(.*\):vi/vi: \1et\2  :vi/'
rg 'vi: .*  :vi' -l -0 | \
  xargs -0 sed -i '' 's/vi: \(.*\)xoet\(.*\):vi/vi: \1noet\2:vi/'
```
2023-12-07 22:17:11 -05:00

58 lines
2.7 KiB
C

/*-*- mode:c;indent-tabs-mode:nil;c-basic-offset:2;tab-width:8;coding:utf-8 -*-│
│ vi: set et 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/dns/dnsheader.h"
#include "libc/serialize.h"
#include "libc/sysv/errfuns.h"
/**
* Serializes DNS message h to wire.
*
* @return number of bytes written (always 12) or -1 w/ errno
* @see pascalifydnsname()
*/
void SerializeDnsHeader(uint8_t p[restrict 12], const struct DnsHeader *h) {
p[0x0] = h->id >> 8;
p[0x1] = h->id;
p[0x2] = h->bf1;
p[0x3] = h->bf2;
p[0x4] = h->qdcount >> 8;
p[0x5] = h->qdcount;
p[0x6] = h->ancount >> 8;
p[0x7] = h->ancount;
p[0x8] = h->nscount >> 8;
p[0x9] = h->nscount;
p[0xa] = h->arcount >> 8;
p[0xb] = h->arcount;
}
/**
* Serializes DNS message h to wire.
*
* @return number of bytes read (always 12) or -1 w/ errno
*/
void DeserializeDnsHeader(struct DnsHeader *h, const uint8_t p[restrict 12]) {
h->id = READ16BE(p);
h->bf1 = p[2];
h->bf2 = p[3];
h->qdcount = READ16BE(p + 4);
h->ancount = READ16BE(p + 6);
h->nscount = READ16BE(p + 8);
h->arcount = READ16BE(p + 10);
}