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#include <assert.h>
#include <inttypes.h>
#include <stdio.h>
#include <getdns_libevent.h>
/* Set up the callback function, which will also do the processing of the results */
void callback(getdns_context *context,
getdns_callback_type_t callback_type,
getdns_dict *response,
void *userarg,
getdns_transaction_t transaction_id)
{
getdns_return_t r; /* Holder for all function returns */
getdns_list *answer;
size_t n_answers, i;
(void) context; (void) userarg; /* unused parameters */
switch(callback_type) {
case GETDNS_CALLBACK_CANCEL:
printf("Transaction with ID %"PRIu64" was cancelled.\n", transaction_id);
return;
case GETDNS_CALLBACK_TIMEOUT:
printf("Transaction with ID %"PRIu64" timed out.\n", transaction_id);
return;
case GETDNS_CALLBACK_ERROR:
printf("An error occurred for transaction ID %"PRIu64".\n", transaction_id);
return;
default: break;
}
assert( callback_type == GETDNS_CALLBACK_COMPLETE );
if ((r = getdns_dict_get_list(response, "/replies_tree/0/answer", &answer)))
fprintf(stderr, "Could not get \"answer\" section from first reply in the response");
else if ((r = getdns_list_get_length(answer, &n_answers)))
fprintf(stderr, "Could not get replies_tree\'s length");
else for (i = 0; i < n_answers && r == GETDNS_RETURN_GOOD; i++) {
getdns_dict *rr;
getdns_bindata *dname;
char *dname_str;
if ((r = getdns_list_get_dict(answer, i, &rr)))
fprintf(stderr, "Could not get rr %zu from answer section", i);
else if (getdns_dict_get_bindata(rr, "/rdata/ptrdname", &dname))
continue; /* Not a PTR */
else if ((r = getdns_convert_dns_name_to_fqdn(dname, &dname_str)))
fprintf(stderr, "Could not convert PTR dname to string");
else {
printf("The dname is %s\n", dname_str);
free(dname_str);
}
}
if (r) {
assert( r != GETDNS_RETURN_GOOD );
fprintf(stderr, ": %d\n", r);
}
getdns_dict_destroy(response);
}
int main()
{
getdns_return_t r; /* Holder for all function returns */
getdns_context *context = NULL;
struct event_base *event_base = NULL;
getdns_bindata address_type = { 4, (void *)"IPv4" };
getdns_bindata address_data = { 4, (void *)"\x08\x08\x08\x08" };
getdns_dict *address = NULL;
getdns_dict *extensions = NULL;
/* Could add things here to help identify this call */
char *userarg = NULL;
getdns_transaction_t transaction_id;
if ((r = getdns_context_create(&context, 1)))
fprintf(stderr, "Trying to create the context failed");
else if (!(event_base = event_base_new()))
fprintf(stderr, "Trying to create the event base failed.\n");
else if ((r = getdns_extension_set_libevent_base(context, event_base)))
fprintf(stderr, "Setting the event base failed");
else if (!(address = getdns_dict_create()))
fprintf(stderr, "Could not create address dict.\n");
else if ((r = getdns_dict_set_bindata(address, "address_type", &address_type)))
fprintf(stderr, "Could not set address_type in address dict.\n");
else if ((r = getdns_dict_set_bindata(address, "address_data", &address_data)))
fprintf(stderr, "Could not set address_data in address dict.\n");
else if ((r = getdns_hostname( context, address, extensions
, userarg, &transaction_id, callback)))
fprintf(stderr, "Error scheduling asynchronous request");
else if (event_base_dispatch(event_base) < 0)
fprintf(stderr, "Error dispatching events\n");
/* Clean up */
if (event_base)
event_base_free(event_base);
if (context)
getdns_context_destroy(context);
/* Assuming we get here, leave gracefully */
exit(EXIT_SUCCESS);
}
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