#include <string.h>

#include <sys/types.h>

#include <sys/socket.h>

#include <arpa/inet.h>

#include <stdio.h>

#include <netinet/in.h>

#include <arpa/nameser.h>

#include <resolv.h>

#include <assert.h>

#include <signal.h>

#include <errno.h>

#include "sd-resolve.h"

#include "resolve-util.h"

#include "macro.h"

int main(int argc, char *argv[]) {

int r = 1, ret;

_cleanup_resolve_free_ sd_resolve *resolve = NULL;

_cleanup_resolve_addrinfo_free_ struct addrinfo *ai = NULL;

_cleanup_free_ unsigned char *srv = NULL;

sd_resolve_query *q1, *q2, *q3;

struct addrinfo hints = {};

struct sockaddr_in sa = {};

char host[NI_MAXHOST] = "", serv[NI_MAXSERV] = "";

signal(SIGCHLD, SIG_IGN);

resolve = sd_resolve_new(2);

if (!resolve)

log_oom();

/* Make a name -> address query */

hints.ai_family = PF_UNSPEC;

hints.ai_socktype = SOCK_STREAM;

q1 = sd_resolve_getaddrinfo(resolve, argc >= 2 ? argv[1] : "www.heise.de", NULL, &hints);

if (!q1)

fprintf(stderr, "sd_resolve_getaddrinfo(): %s\n", strerror(errno));

/* Make an address -> name query */

sa.sin_family = AF_INET;

sa.sin_addr.s_addr = inet_addr(argc >= 3 ? argv[2] : "193.99.144.71");

sa.sin_port = htons(80);

q2 = sd_resolve_getnameinfo(resolve, (struct sockaddr*) &sa, sizeof(sa), 0, 1, 1);

if (!q2)

fprintf(stderr, "sd_resolve_getnameinfo(): %s\n", strerror(errno));

/* Make a res_query() call */

q3 = sd_resolve_res_query(resolve, "_xmpp-client._tcp.gmail.com", C_IN, T_SRV);

if (!q3)

fprintf(stderr, "sd_resolve_res_query(): %s\n", strerror(errno));

/* Wait until the three queries are completed */

while (!sd_resolve_isdone(resolve, q1) ||

!sd_resolve_isdone(resolve, q2) ||

!sd_resolve_isdone(resolve, q3)) {

if (sd_resolve_wait(resolve, 1) < 0)

fprintf(stderr, "sd_resolve_wait(): %s\n", strerror(errno));

}

/* Interpret the result of the name -> addr query */

ret = sd_resolve_getaddrinfo_done(resolve, q1, &ai);

if (ret)

fprintf(stderr, "error: %s %i\n", gai_strerror(ret), ret);

else {

struct addrinfo *i;

for (i = ai; i; i = i->ai_next) {

char t[256];

const char *p = NULL;

if (i->ai_family == PF_INET)

p = inet_ntop(AF_INET, &((struct sockaddr_in*) i->ai_addr)->sin_addr, t, sizeof(t));

else if (i->ai_family == PF_INET6)

p = inet_ntop(AF_INET6, &((struct sockaddr_in6*) i->ai_addr)->sin6_addr, t, sizeof(t));

printf("%s\n", p);

}

}

/* Interpret the result of the addr -> name query */

ret = sd_resolve_getnameinfo_done(resolve, q2, host, sizeof(host), serv, sizeof(serv));

if (ret)

fprintf(stderr, "error: %s %i\n", gai_strerror(ret), ret);

else

printf("%s -- %s\n", host, serv);

/* Interpret the result of the SRV lookup */

ret = sd_resolve_res_done(resolve, q3, &srv);

if (ret < 0) {

fprintf(stderr, "error: %s %i\n", strerror(errno), ret);

} else if (ret == 0) {

fprintf(stderr, "No reply for SRV lookup\n");

} else {

int qdcount;

int ancount;

int len;

const unsigned char *pos = srv + sizeof(HEADER);

unsigned char *end = srv + ret;

HEADER *head = (HEADER *)srv;

char name[256];

qdcount = ntohs(head->qdcount);

ancount = ntohs(head->ancount);

printf("%d answers for srv lookup:\n", ancount);

/* Ignore the questions */

while (qdcount-- > 0 && (len = dn_expand(srv, end, pos, name, 255)) >= 0) {

assert(len >= 0);

pos += len + QFIXEDSZ;

}

/* Parse the answers */

while (ancount-- > 0 && (len = dn_expand(srv, end, pos, name, 255)) >= 0) {

/* Ignore the initial string */

uint16_t pref, weight, port;

assert(len >= 0);

pos += len;

/* Ignore type, ttl, class and dlen */

pos += 10;

GETSHORT(pref, pos);

GETSHORT(weight, pos);

GETSHORT(port, pos);

len = dn_expand(srv, end, pos, name, 255);

printf("\tpreference: %2d weight: %2d port: %d host: %s\n",

pref, weight, port, name);

pos += len;

}

}

r = 0;

return r;

}