118 lines
4.0 KiB
C++
118 lines
4.0 KiB
C++
/*
|
|
* Copyright 2021 The WebRTC Project Authors. All rights reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#ifndef API_WRAPPING_ASYNC_DNS_RESOLVER_H_
|
|
#define API_WRAPPING_ASYNC_DNS_RESOLVER_H_
|
|
|
|
#include <functional>
|
|
#include <memory>
|
|
|
|
#include "absl/memory/memory.h"
|
|
#include "api/async_dns_resolver.h"
|
|
#include "api/sequence_checker.h"
|
|
#include "rtc_base/async_resolver.h"
|
|
#include "rtc_base/async_resolver_interface.h"
|
|
#include "rtc_base/checks.h"
|
|
#include "rtc_base/socket_address.h"
|
|
#include "rtc_base/third_party/sigslot/sigslot.h"
|
|
#include "rtc_base/thread_annotations.h"
|
|
|
|
// This file defines a DNS resolver that wraps an old-style
|
|
// AsyncResolver.
|
|
// It is part of the conversion to the newer interface, and will go away
|
|
// once conversion is finished.
|
|
// TODO(bugs.webrtc.org/12598): Delete this API.
|
|
|
|
namespace webrtc {
|
|
|
|
class WrappingAsyncDnsResolver;
|
|
|
|
class RTC_EXPORT WrappingAsyncDnsResolverResult
|
|
: public AsyncDnsResolverResult {
|
|
public:
|
|
explicit WrappingAsyncDnsResolverResult(WrappingAsyncDnsResolver* owner)
|
|
: owner_(owner) {}
|
|
~WrappingAsyncDnsResolverResult() {}
|
|
|
|
// Note: Inline declaration not possible, since it refers to
|
|
// WrappingAsyncDnsResolver.
|
|
bool GetResolvedAddress(int family, rtc::SocketAddress* addr) const override;
|
|
int GetError() const override;
|
|
|
|
private:
|
|
WrappingAsyncDnsResolver* const owner_;
|
|
};
|
|
|
|
class RTC_EXPORT WrappingAsyncDnsResolver : public AsyncDnsResolverInterface,
|
|
public sigslot::has_slots<> {
|
|
public:
|
|
explicit WrappingAsyncDnsResolver(rtc::AsyncResolverInterface* wrapped)
|
|
: wrapped_(absl::WrapUnique(wrapped)), result_(this) {}
|
|
|
|
~WrappingAsyncDnsResolver() override {
|
|
// Workaround to get around the fact that sigslot-using objects can't be
|
|
// destroyed from within their callback: Alert class users early.
|
|
// TODO(bugs.webrtc.org/12651): Delete this class once the sigslot users are
|
|
// gone.
|
|
RTC_CHECK(!within_resolve_result_);
|
|
wrapped_.release()->Destroy(false);
|
|
}
|
|
|
|
void Start(const rtc::SocketAddress& addr,
|
|
std::function<void()> callback) override {
|
|
RTC_DCHECK_RUN_ON(&sequence_checker_);
|
|
RTC_DCHECK_EQ(State::kNotStarted, state_);
|
|
state_ = State::kStarted;
|
|
callback_ = callback;
|
|
wrapped_->SignalDone.connect(this,
|
|
&WrappingAsyncDnsResolver::OnResolveResult);
|
|
wrapped_->Start(addr);
|
|
}
|
|
|
|
const AsyncDnsResolverResult& result() const override {
|
|
RTC_DCHECK_RUN_ON(&sequence_checker_);
|
|
RTC_DCHECK_EQ(State::kResolved, state_);
|
|
return result_;
|
|
}
|
|
|
|
private:
|
|
enum class State { kNotStarted, kStarted, kResolved };
|
|
|
|
friend class WrappingAsyncDnsResolverResult;
|
|
// For use by WrappingAsyncDnsResolverResult
|
|
rtc::AsyncResolverInterface* wrapped() const {
|
|
RTC_DCHECK_RUN_ON(&sequence_checker_);
|
|
return wrapped_.get();
|
|
}
|
|
|
|
void OnResolveResult(rtc::AsyncResolverInterface* ref) {
|
|
RTC_DCHECK_RUN_ON(&sequence_checker_);
|
|
RTC_DCHECK(state_ == State::kStarted);
|
|
RTC_DCHECK_EQ(ref, wrapped_.get());
|
|
state_ = State::kResolved;
|
|
within_resolve_result_ = true;
|
|
callback_();
|
|
within_resolve_result_ = false;
|
|
}
|
|
|
|
// The class variables need to be accessed on a single thread.
|
|
SequenceChecker sequence_checker_;
|
|
std::function<void()> callback_ RTC_GUARDED_BY(sequence_checker_);
|
|
std::unique_ptr<rtc::AsyncResolverInterface> wrapped_
|
|
RTC_GUARDED_BY(sequence_checker_);
|
|
State state_ RTC_GUARDED_BY(sequence_checker_) = State::kNotStarted;
|
|
WrappingAsyncDnsResolverResult result_ RTC_GUARDED_BY(sequence_checker_);
|
|
bool within_resolve_result_ RTC_GUARDED_BY(sequence_checker_) = false;
|
|
};
|
|
|
|
} // namespace webrtc
|
|
|
|
#endif // API_WRAPPING_ASYNC_DNS_RESOLVER_H_
|