blob: fb5becf1e62a9a8fb4a554b09be95611553ffcfd [file] [log] [blame]
/*
*
* Copyright (c) 2020 Project CHIP Authors
* Copyright (c) 2017 Nest Labs, Inc.
*
* Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/**
* @file
* This file defines the AsyncDNSResolver, the object that performs
* Asynchronous Domain Name System (DNS) resolution in InetLayer.
*
*/
#pragma once
#include <inet/IPAddress.h>
#include <inet/InetError.h>
#if INET_CONFIG_ENABLE_DNS_RESOLVER
#include <inet/DNSResolver.h>
#endif // INET_CONFIG_ENABLE_DNS_RESOLVER
#if CHIP_SYSTEM_CONFIG_USE_SOCKETS
#if INET_CONFIG_ENABLE_DNS_RESOLVER && INET_CONFIG_ENABLE_ASYNC_DNS_SOCKETS
#include <netdb.h>
#include <pthread.h>
#include <semaphore.h>
namespace chip {
namespace Inet {
/**
* @class AsyncDNSResolverSockets
*
* @brief
* This is an internal class to InetLayer that provides helper APIs for
* Asynchronous Domain Name System (DNS) resolution in InetLayer.
* There is no public interface available for the application layer.
*
*/
class AsyncDNSResolverSockets
{
friend class InetLayer;
friend class DNSResolver;
public:
INET_ERROR EnqueueRequest(DNSResolver & resolver);
INET_ERROR Init(InetLayer * inet);
INET_ERROR Cancel(DNSResolver & resolver);
INET_ERROR Shutdown();
INET_ERROR PrepareDNSResolver(DNSResolver & resolver, const char * hostName, uint16_t hostNameLen, uint8_t options,
uint8_t maxAddrs, IPAddress * addrArray, DNSResolver::OnResolveCompleteFunct onComplete,
void * appState);
private:
pthread_t mAsyncDNSThreadHandle[INET_CONFIG_DNS_ASYNC_MAX_THREAD_COUNT];
pthread_mutex_t mAsyncDNSMutex; /* Mutex for accessing the DNSResolver queue. */
pthread_cond_t mAsyncDNSCondVar; /* Condition Variable for thread synchronization. */
volatile DNSResolver * mAsyncDNSQueueHead; /* The head of the asynchronous DNSResolver object queue. */
volatile DNSResolver * mAsyncDNSQueueTail; /* The tail of the asynchronous DNSResolver object queue. */
InetLayer * mInet; /* The pointer to the InetLayer. */
static void
DNSResultEventHandler(chip::System::Layer * aLayer, void * aAppState,
chip::System::Error aError); /* Timer event handler function for asynchronous DNS notification */
INET_ERROR DequeueRequest(DNSResolver ** outResolver);
bool ShouldThreadShutdown();
void Resolve(DNSResolver & resolver);
void UpdateDNSResult(DNSResolver & resolver, struct addrinfo * lookupRes);
static void * AsyncDNSThreadRun(void * args);
static void NotifyChipThread(DNSResolver * resolver);
void AsyncMutexLock();
void AsyncMutexUnlock();
};
} // namespace Inet
} // namespace chip
#endif // INET_CONFIG_ENABLE_DNS_RESOLVER && INET_CONFIG_ENABLE_ASYNC_DNS_SOCKETS
#endif // CHIP_SYSTEM_CONFIG_USE_SOCKETS