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#ifdef _WIN32
# define _CRT_SECURE_NO_WARNINGS 1
#endif
#include "mdns.h"
#include <stdio.h>
#include <errno.h>
#ifdef _WIN32
# define sleep(x) Sleep(x * 1000)
#else
# include <netdb.h>
#endif
static char addrbuffer[64];
static char namebuffer[256];
static mdns_record_txt_t txtbuffer[128];
static mdns_string_t
ipv4_address_to_string(char* buffer, size_t capacity, const struct sockaddr_in* addr) {
char host[NI_MAXHOST] = {0};
char service[NI_MAXSERV] = {0};
int ret = getnameinfo((const struct sockaddr*)addr, sizeof(struct sockaddr_in),
host, NI_MAXHOST, service, NI_MAXSERV,
NI_NUMERICSERV | NI_NUMERICHOST);
int len = 0;
if (ret == 0) {
if (addr->sin_port != 0)
len = snprintf(buffer, capacity, "%s:%s", host, service);
else
len = snprintf(buffer, capacity, "%s", host);
}
if (len >= (int)capacity)
len = (int)capacity - 1;
mdns_string_t str = {buffer, len};
return str;
}
static mdns_string_t
ipv6_address_to_string(char* buffer, size_t capacity, const struct sockaddr_in6* addr) {
char host[NI_MAXHOST] = {0};
char service[NI_MAXSERV] = {0};
int ret = getnameinfo((const struct sockaddr*)addr, sizeof(struct sockaddr_in6),
host, NI_MAXHOST, service, NI_MAXSERV,
NI_NUMERICSERV | NI_NUMERICHOST);
int len = 0;
if (ret == 0) {
if (addr->sin6_port != 0)
len = snprintf(buffer, capacity, "[%s]:%s", host, service);
else
len = snprintf(buffer, capacity, "%s", host);
}
if (len >= (int)capacity)
len = (int)capacity - 1;
mdns_string_t str = {buffer, len};
return str;
}
static mdns_string_t
ip_address_to_string(char* buffer, size_t capacity, const struct sockaddr* addr) {
if (addr->sa_family == AF_INET6)
return ipv6_address_to_string(buffer, capacity, (const struct sockaddr_in6*)addr);
return ipv4_address_to_string(buffer, capacity, (const struct sockaddr_in*)addr);
}
static int
callback(const struct sockaddr* from,
mdns_entry_type_t entry, uint16_t type,
uint16_t rclass, uint32_t ttl,
const void* data, size_t size, size_t offset, size_t length,
void* user_data) {
mdns_string_t fromaddrstr = ip_address_to_string(addrbuffer, sizeof(addrbuffer), from);
const char* entrytype = (entry == MDNS_ENTRYTYPE_ANSWER) ? "answer" :
((entry == MDNS_ENTRYTYPE_AUTHORITY) ? "authority" : "additional");
if (type == MDNS_RECORDTYPE_PTR) {
mdns_string_t namestr = mdns_record_parse_ptr(data, size, offset, length,
namebuffer, sizeof(namebuffer));
INFO("%.*s : %s PTR %.*s type %u rclass 0x%x ttl %u length %d\n",
MDNS_STRING_FORMAT(fromaddrstr), entrytype,
MDNS_STRING_FORMAT(namestr), type, rclass, ttl, (int)length);
}
else if (type == MDNS_RECORDTYPE_SRV) {
mdns_record_srv_t srv = mdns_record_parse_srv(data, size, offset, length,
namebuffer, sizeof(namebuffer));
INFO("%.*s : %s SRV %.*s priority %d weight %d port %d\n",
MDNS_STRING_FORMAT(fromaddrstr), entrytype,
MDNS_STRING_FORMAT(srv.name), srv.priority, srv.weight, srv.port);
}
else if (type == MDNS_RECORDTYPE_A) {
struct sockaddr_in addr;
mdns_record_parse_a(data, size, offset, length, &addr);
mdns_string_t addrstr = ipv4_address_to_string(namebuffer, sizeof(namebuffer), &addr);
INFO("%.*s : %s A %.*s\n",
MDNS_STRING_FORMAT(fromaddrstr), entrytype,
MDNS_STRING_FORMAT(addrstr));
}
else if (type == MDNS_RECORDTYPE_AAAA) {
struct sockaddr_in6 addr;
mdns_record_parse_aaaa(data, size, offset, length, &addr);
mdns_string_t addrstr = ipv6_address_to_string(namebuffer, sizeof(namebuffer), &addr);
INFO("%.*s : %s AAAA %.*s\n",
MDNS_STRING_FORMAT(fromaddrstr), entrytype,
MDNS_STRING_FORMAT(addrstr));
}
else if (type == MDNS_RECORDTYPE_TXT) {
size_t parsed = mdns_record_parse_txt(data, size, offset, length,
txtbuffer, sizeof(txtbuffer) / sizeof(mdns_record_txt_t));
for (size_t itxt = 0; itxt < parsed; ++itxt) {
if (txtbuffer[itxt].value.length) {
INFO("%.*s : %s TXT %.*s = %.*s\n",
MDNS_STRING_FORMAT(fromaddrstr), entrytype,
MDNS_STRING_FORMAT(txtbuffer[itxt].key),
MDNS_STRING_FORMAT(txtbuffer[itxt].value));
}
else {
INFO("%.*s : %s TXT %.*s\n",
MDNS_STRING_FORMAT(fromaddrstr), entrytype,
MDNS_STRING_FORMAT(txtbuffer[itxt].key));
}
}
}
else {
INFO("%.*s : %s type %u rclass 0x%x ttl %u length %d\n",
MDNS_STRING_FORMAT(fromaddrstr), entrytype,
type, rclass, ttl, (int)length);
}
return 0;
}
int
main() {
size_t capacity = 2048;
void* buffer = 0;
void* user_data = 0;
size_t records;
#ifdef _WIN32
WORD versionWanted = MAKEWORD(1, 1);
WSADATA wsaData;
WSAStartup(versionWanted, &wsaData);
#endif
int sock = mdns_socket_open_ipv4();
if (sock < 0) {
INFO("Failed to open socket: %s\n", strerror(errno));
return -1;
}
INFO("Opened IPv4 socket for mDNS/DNS-SD\n");
buffer = malloc(capacity);
/*
INFO("Sending DNS-SD discovery\n");
if (mdns_discovery_send(sock)) {
INFO("Failed to send DNS-DS discovery: %s\n", strerror(errno));
goto quit;
}
INFO("Reading DNS-SD replies\n");
for (int i = 0; i < 10; ++i) {
records = mdns_discovery_recv(sock, buffer, capacity, callback,
user_data);
sleep(1);
}
*/
INFO("Sending mDNS query\n");
if (mdns_query_send(sock, MDNS_RECORDTYPE_PTR,
MDNS_STRING_CONST("_hicn._udp.local."),
buffer, capacity)) {
INFO("Failed to send mDNS query: %s\n", strerror(errno));
goto quit;
}
INFO("Reading mDNS replies\n");
for (int i = 0; i < 10; ++i) {
records = mdns_query_recv(sock, buffer, capacity, callback, user_data, 1);
sleep(1);
}
quit:
free(buffer);
mdns_socket_close(sock);
INFO("Closed socket\n");
#ifdef _WIN32
WSACleanup();
#endif
return 0;
}
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