getdns/src/sync.c

/**
 *
 * /brief getdns core functions for synchronous use
 *
 * Originally taken from the getdns API description pseudo implementation.
 *
 */
/* The MIT License (MIT)
 * Copyright (c) 2013 Verisign, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * 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 OR COPYRIGHT HOLDERS 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 OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#include <getdns/getdns.h>
#include <pthread.h>
#include <event2/event.h>
#include <unbound-event.h>
#include "context.h"
#include "general.h"
#include <string.h>

/* stuff to make it compile pedantically */
#define UNUSED_PARAM(x) ((void)(x))

/* struct used for the request */
typedef struct sync_request_data {
    getdns_context_t context;
    char* name;
    uint16_t request_type;
    getdns_dict *extensions;
    getdns_return_t response_status;
    getdns_dict **response;
} sync_request_data;

static void sync_callback_func(getdns_context_t context,
                               uint16_t callback_type,
                               struct getdns_dict *response,
                               void *userarg,
                               getdns_transaction_t transaction_id) {
    sync_request_data* req_data = userarg;
    *(req_data->response) = response;
}

static void * request_thread_start(void *arg) {
    struct sync_request_data *req_data = arg;

    req_data->response_status = getdns_general_ub(req_data->context->unbound_sync,
                                                  req_data->context->event_base_sync,
                                                  req_data->context,
                                                  req_data->name,
                                                  req_data->request_type,
                                                  req_data->extensions,
                                                  req_data,
                                                  NULL,
                                                  sync_callback_func);

    event_base_dispatch(req_data->context->event_base_sync);
    return NULL;
}


getdns_return_t
getdns_general_sync(
  getdns_context_t       context,
  const char             *name,
  uint16_t               request_type,
  struct getdns_dict     *extensions,
  uint32_t               *response_length,
  struct getdns_dict     **response
)
{
    /* we will cheat and spawn a thread */
    /* set up for sync resolution */
    pthread_t thread;
    pthread_attr_t attr;
    sync_request_data req_data = {
        context,
        strdup(name),
        request_type,
        extensions,
        GETDNS_RETURN_GOOD,
        response
    };

    /* create the thread */
    int ret = pthread_attr_init(&attr);
    if (ret != 0) {
        free(req_data.name);
        return GETDNS_RETURN_GENERIC_ERROR;
    }
    ret = pthread_create(&thread, &attr, request_thread_start, &req_data);
    if (ret != 0) {
        pthread_attr_destroy(&attr);
        free(req_data.name);
        return GETDNS_RETURN_GENERIC_ERROR;
    }
    /* wait for the thread */
    ret = pthread_join(thread, NULL);
    /* delete attr */
    pthread_attr_destroy(&attr);
    if (ret != 0) {
        free(req_data.name);
        return GETDNS_RETURN_GENERIC_ERROR;
    }
    free(req_data.name);
    return req_data.response_status;
}

getdns_return_t
getdns_address_sync(
  getdns_context_t       context,
  const char             *name,
  struct getdns_dict     *extensions,
  uint32_t               *response_length,
  struct getdns_dict     **response
)
{
    int cleanup_extensions = 0;
    if (!extensions) {
        extensions = getdns_dict_create();
        cleanup_extensions = 1;
    }
    getdns_dict_set_int(extensions,
                        GETDNS_STR_EXTENSION_RETURN_BOTH_V4_AND_V6,
                        GETDNS_EXTENSION_TRUE);

    getdns_return_t result =
    getdns_general_sync(context, name, GETDNS_RRTYPE_A,
                        extensions, response_length, response);
    if (cleanup_extensions) {
        getdns_dict_destroy(extensions);
    }
    return result;
}

getdns_return_t
getdns_hostname_sync(
  getdns_context_t       context,
  struct getdns_dict     *address,
  struct getdns_dict     *extensions,
  uint32_t               *response_length,
  struct getdns_dict     **response
)
{ UNUSED_PARAM(context); UNUSED_PARAM(address); UNUSED_PARAM(extensions);
UNUSED_PARAM(response_length); UNUSED_PARAM(response); return GETDNS_RETURN_GOOD; }

getdns_return_t
getdns_service_sync(
  getdns_context_t       context,
  const char             *name,
  struct getdns_dict     *extensions,
  uint32_t               *response_length,
  struct getdns_dict     **response
)
{

    return getdns_general_sync(context, name, GETDNS_RRTYPE_SRV, extensions,
                               response_length, response);

}

void
getdns_free_sync_request_memory(
  struct getdns_dict     *response
)
{ UNUSED_PARAM(response); }

/* getdns_core_sync.c */