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/*
* This file is part of the Nice GLib ICE library.
*
* (C) 2006, 2007 Collabora Ltd.
* Contact: Dafydd Harries
* (C) 2006, 2007 Nokia Corporation. All rights reserved.
* Contact: Kai Vehmanen
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is the Nice GLib ICE library.
*
* The Initial Developers of the Original Code are Collabora Ltd and Nokia
* Corporation. All Rights Reserved.
*
* Contributors:
* Dafydd Harries, Collabora Ltd.
* Kai Vehmanen, Nokia
*
* Alternatively, the contents of this file may be used under the terms of the
* the GNU Lesser General Public License Version 2.1 (the "LGPL"), in which
* case the provisions of LGPL are applicable instead of those above. If you
* wish to allow use of your version of this file only under the terms of the
* LGPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replace
* them with the notice and other provisions required by the LGPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the LGPL.
*/
/**
* @file candidate.c
* @brief ICE candidate functions
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#else
#define NICEAPI_EXPORT
#endif
#include <string.h>
#include "agent.h"
#include "component.h"
/* (ICE 4.1.1 "Gathering Candidates") ""Every candidate is a transport
* address. It also has a type and a base. Three types are defined and
* gathered by this specification - host candidates, server reflexive
* candidates, and relayed candidates."" (ID-19) */
NICEAPI_EXPORT NiceCandidate *
nice_candidate_new (NiceCandidateType type)
{
NiceCandidate *candidate;
candidate = g_slice_new0 (NiceCandidate);
candidate->type = type;
return candidate;
}
NICEAPI_EXPORT void
nice_candidate_free (NiceCandidate *candidate)
{
/* better way of checking if socket is allocated? */
if (candidate->username)
g_free (candidate->username);
if (candidate->password)
g_free (candidate->password);
g_slice_free (NiceCandidate, candidate);
}
guint32
nice_candidate_jingle_priority (NiceCandidate *candidate)
{
switch (candidate->type)
{
case NICE_CANDIDATE_TYPE_HOST: return 1000;
case NICE_CANDIDATE_TYPE_SERVER_REFLEXIVE: return 900;
case NICE_CANDIDATE_TYPE_PEER_REFLEXIVE: return 900;
case NICE_CANDIDATE_TYPE_RELAYED: return 500;
}
/* appease GCC */
return 0;
}
guint32
nice_candidate_msn_priority (NiceCandidate *candidate)
{
switch (candidate->type)
{
case NICE_CANDIDATE_TYPE_HOST: return 830;
case NICE_CANDIDATE_TYPE_SERVER_REFLEXIVE: return 550;
case NICE_CANDIDATE_TYPE_PEER_REFLEXIVE: return 550;
case NICE_CANDIDATE_TYPE_RELAYED: return 450;
}
/* appease GCC */
return 0;
}
/**
* ICE 4.1.2.1. "Recommended Formula" (ID-19):
* returns number between 1 and 0x7effffff
*/
guint32
nice_candidate_ice_priority_full (
// must be ∈ (0, 126) (max 2^7 - 2)
guint type_preference,
// must be ∈ (0, 65535) (max 2^16 - 1)
guint local_preference,
// must be ∈ (0, 255) (max 2 ^ 8 - 1)
guint component_id)
{
return (
0x1000000 * type_preference +
0x100 * local_preference +
(0x100 - component_id));
}
guint32
nice_candidate_ice_priority (const NiceCandidate *candidate)
{
guint8 type_preference = 0;
switch (candidate->type)
{
case NICE_CANDIDATE_TYPE_HOST:
type_preference = NICE_CANDIDATE_TYPE_PREF_HOST; break;
case NICE_CANDIDATE_TYPE_PEER_REFLEXIVE:
type_preference = NICE_CANDIDATE_TYPE_PREF_PEER_REFLEXIVE; break;
case NICE_CANDIDATE_TYPE_SERVER_REFLEXIVE:
type_preference = NICE_CANDIDATE_TYPE_PREF_SERVER_REFLEXIVE; break;
case NICE_CANDIDATE_TYPE_RELAYED:
type_preference = NICE_CANDIDATE_TYPE_PREF_RELAYED; break;
}
/* return _candidate_ice_priority (type_preference, 1, candidate->component_id); */
return nice_candidate_ice_priority_full (type_preference, 1, candidate->component_id);
}
/**
* Calculates the pair priority as specified in ICE
* sect 5.7.2. "Computing Pair Priority and Ordering Pairs" (ID-19).
*/
guint64
nice_candidate_pair_priority (guint32 o_prio, guint32 a_prio)
{
guint32 max = o_prio > a_prio ? o_prio : a_prio;
guint32 min = o_prio < a_prio ? o_prio : a_prio;
return ((guint64)1 << 32) * min + 2 * max + (o_prio > a_prio ? 1 : 0);
}
/**
* Copies a candidate
*/
NICEAPI_EXPORT NiceCandidate *
nice_candidate_copy (const NiceCandidate *candidate)
{
NiceCandidate *copy = nice_candidate_new (candidate->type);
memcpy (copy, candidate, sizeof(NiceCandidate));
copy->username = g_strdup (copy->username);
copy->password = g_strdup (copy->password);
return copy;
}
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