/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */

/*

 * Copyright (C) 2008 Imendio AB

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public License as

 * published by the Free Software Foundation; either version 2 of the

 * License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this program; if not, see <https://www.gnu.org/licenses>

 */

#include <config.h>

#include <string.h>

#include <sys/types.h>

#include <netdb.h>

/* Needed on Mac OS X */

#if HAVE_ARPA_NAMESER_COMPAT_H

#include <arpa/nameser_compat.h>

#endif

#include <netinet/in.h>

#include <arpa/nameser.h>

#include <resolv.h>

#include "lm-marshal.h"

#include "lm-misc.h"

#include "lm-blocking-resolver.h"

#define SRV_LEN 8192

#define GET_PRIV(obj) (lm_blocking_resolver_get_instance_private (LM_BLOCKING_RESOLVER(obj)))

typedef struct LmBlockingResolverPrivate LmBlockingResolverPrivate;

struct LmBlockingResolverPrivate {

    GSource *idle_source;

};

static void     blocking_resolver_dispose     (GObject       *object);

static void     blocking_resolver_lookup      (LmResolver    *resolver);

static void     blocking_resolver_cancel      (LmResolver    *resolver);

G_DEFINE_TYPE_WITH_PRIVATE (LmBlockingResolver, lm_blocking_resolver, LM_TYPE_RESOLVER)

static void

lm_blocking_resolver_class_init (LmBlockingResolverClass *class)

{

    GObjectClass    *object_class   = G_OBJECT_CLASS (class);

    LmResolverClass *resolver_class = LM_RESOLVER_CLASS (class);

    object_class->dispose = blocking_resolver_dispose;

    resolver_class->lookup = blocking_resolver_lookup;

    resolver_class->cancel = blocking_resolver_cancel;

}

static void

lm_blocking_resolver_init (LmBlockingResolver *blocking_resolver)

{

}

static void

blocking_resolver_dispose (GObject *object)

{

    /* Ensure we don't have an idle around */

    blocking_resolver_cancel (LM_RESOLVER (object));

    (G_OBJECT_CLASS (lm_blocking_resolver_parent_class)->dispose) (object);

}

static gboolean

blocking_resolver_lookup_host (LmBlockingResolver *resolver)

{

    gchar           *host;

    struct addrinfo  req;

    struct addrinfo *ans;

    int              err;

    gboolean         retval = TRUE;

    g_object_get (resolver, "host", &host, NULL);

    /* Lookup */

    memset (&req, 0, sizeof(req));

    req.ai_family   = PF_UNSPEC;

    req.ai_socktype = SOCK_STREAM;

    req.ai_protocol = IPPROTO_TCP;

    err = getaddrinfo (host, NULL, &req, &ans);

    if (err != 0) {

        _lm_resolver_set_result (LM_RESOLVER (resolver), LM_RESOLVER_RESULT_FAILED,

                                 NULL);

        retval = FALSE;

        _lm_resolver_set_result (LM_RESOLVER (resolver), LM_RESOLVER_RESULT_OK,

                                 ans);

    }

    g_free (host);

    return retval;

}

static gboolean

blocking_resolver_lookup_service (LmBlockingResolver *resolver)

{

    gchar *domain;

    gchar *service;

    gchar *protocol;

    gchar *srv;

    gchar *new_server = NULL;

    guint  new_port = 0;

    gboolean  result;

    unsigned char    srv_ans[SRV_LEN];

    int              len;

    gboolean         retval = TRUE;

    g_object_get (resolver,

                  "domain", &domain,

                  "service", &service,

                  "protocol", &protocol,

                  NULL);

    srv = _lm_resolver_create_srv_string (domain, service, protocol);

    res_init ();

    len = res_query (srv, C_IN, T_SRV, srv_ans, SRV_LEN);

    result = _lm_resolver_parse_srv_response (srv_ans, len,

                                              &new_server, &new_port);

    if (result == FALSE) {

        retval = FALSE;

    }

    g_object_set (resolver,

                  "host", new_server,

                  "port", new_port,

                  NULL);

    g_object_ref (resolver);

    _lm_resolver_set_result (LM_RESOLVER (resolver), LM_RESOLVER_RESULT_OK, NULL);

    g_object_unref (resolver);

    /* Lookup the new server and the new port */

   /* blocking_resolver_lookup_host (resolver); */

    g_free (new_server);

    g_free (srv);

    g_free (domain);

    g_free (service);

    g_free (protocol);

    return retval;

}

static gboolean

blocking_resolver_idle_lookup (LmBlockingResolver *resolver)

{

    LmBlockingResolverPrivate *priv = GET_PRIV (resolver);

    gint                    type;

    /* Start the DNS querying */

    /* Decide if we are going to lookup a srv or host */

    g_object_get (resolver, "type", &type, NULL);

    switch (type) {

    case LM_RESOLVER_HOST:

        blocking_resolver_lookup_host (resolver);

        break;

    case LM_RESOLVER_SRV:

        blocking_resolver_lookup_service (resolver);

        break;

    };

    /* End of DNS querying */

    priv->idle_source = NULL;

    return FALSE;

}

static void

blocking_resolver_lookup (LmResolver *resolver)

{

    LmBlockingResolverPrivate *priv;

    GMainContext           *context;

    g_return_if_fail (LM_IS_BLOCKING_RESOLVER (resolver));

    priv = GET_PRIV (resolver);

    g_object_get (resolver, "context", &context, NULL);

    priv->idle_source = lm_misc_add_idle (context,

                                          (GSourceFunc) blocking_resolver_idle_lookup,

                                          resolver);

}

static void

blocking_resolver_cancel (LmResolver *resolver)

{

    LmBlockingResolverPrivate *priv;

    g_return_if_fail (LM_IS_BLOCKING_RESOLVER (resolver));

    priv = GET_PRIV (resolver);

    if (priv->idle_source) {

        g_source_destroy (priv->idle_source);

        priv->idle_source = NULL;

    }

}