cosmopolitan/libc/dns/gethostbyname.c
Gautham 0ea2907730
Add getservbyname and getservbyport (#204)
For every call of getservbyname/getservbyport the lookup of
/etc/services is done by opening the file and parsing each line
one-by-one. This is slow, but the implementation is simple.

This change also adds fixes for the gethostbyname function.
2021-07-04 16:31:42 -07:00

71 lines
3.7 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│
╞══════════════════════════════════════════════════════════════════════════════╡
│ This is free and unencumbered software released into the public domain. │
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│ Anyone is free to copy, modify, publish, use, compile, sell, or │
│ distribute this software, either in source code form or as a compiled │
│ binary, for any purpose, commercial or non-commercial, and by any │
│ means. │
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│ In jurisdictions that recognize copyright laws, the author or authors │
│ of this software dedicate any and all copyright interest in the │
│ software to the public domain. We make this dedication for the benefit │
│ of the public at large and to the detriment of our heirs and │
│ successors. We intend this dedication to be an overt act of │
│ relinquishment in perpetuity of all present and future rights to this │
│ software under copyright law. │
│ │
│ THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, │
│ EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF │
│ MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. │
│ IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR │
│ OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, │
│ ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR │
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╚─────────────────────────────────────────────────────────────────────────────*/
#include "libc/dns/ent.h"
#include "libc/mem/mem.h"
#include "libc/str/str.h"
#include "libc/sysv/consts/af.h"
struct hostent *gethostbyname(const char *name) {
static struct hostent *ptr0, he0;
static char h_name[DNS_NAME_MAX + 1];
static char *h_aliases[1];
static char *h_addr_list[2];
static char h_addr_list0[4];
struct addrinfo *result = NULL;
if (!ptr0) {
he0.h_name = h_name;
he0.h_aliases = h_aliases;
he0.h_aliases[0] = NULL;
he0.h_addrtype = AF_INET;
he0.h_length = 4;
he0.h_addr_list = h_addr_list;
he0.h_addr_list[0] = h_addr_list0;
he0.h_addr_list[1] = NULL;
ptr0 = &he0;
}
if (getaddrinfo(name, NULL, NULL, &result) || result == NULL) return NULL;
/* if getaddrinfo is successful, result->ai_canonname is non-NULL,
* (see newaddrinfo) but the string can still be empty */
if (result->ai_canonname[0])
memccpy(ptr0->h_name, result->ai_canonname, '\0', DNS_NAME_MAX);
else
memccpy(ptr0->h_name, name, '\0', DNS_NAME_MAX);
*((uint32_t *)ptr0->h_addr_list[0]) = (result->ai_addr4->sin_addr.s_addr);
/* TODO: if result has ai_next, fit multiple entries for h_addr_list */
freeaddrinfo(result);
return ptr0;
}