Revert of Revert of Move service_discovery_client_impl.* into chrome/common.

chrome/common/local_discovery/service_discovery_client_impl.cc

Index: chrome/common/local_discovery/service_discovery_client_impl.cc
diff --git a/chrome/common/local_discovery/service_discovery_client_impl.cc b/chrome/common/local_discovery/service_discovery_client_impl.cc
new file mode 100644
index 0000000000000000000000000000000000000000..b64924e2d4afc06e15958d9877fe2ed619b517b0
--- /dev/null
+++ b/chrome/common/local_discovery/service_discovery_client_impl.cc
@@ -0,0 +1,584 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <utility>
+
+#include "base/logging.h"
+#include "base/memory/singleton.h"
+#include "base/message_loop/message_loop_proxy.h"
+#include "base/stl_util.h"
+#include "chrome/common/local_discovery/service_discovery_client_impl.h"
+#include "net/dns/dns_protocol.h"
+#include "net/dns/record_rdata.h"
+
+namespace local_discovery {
+
+namespace {
+// TODO(noamsml): Make this configurable through the LocalDomainResolver
+// interface.
+const int kLocalDomainSecondAddressTimeoutMs = 100;
+
+const int kInitialRequeryTimeSeconds = 1;
+const int kMaxRequeryTimeSeconds = 2; // Time for last requery
+}
+
+ServiceDiscoveryClientImpl::ServiceDiscoveryClientImpl(
+    net::MDnsClient* mdns_client) : mdns_client_(mdns_client) {
+}
+
+ServiceDiscoveryClientImpl::~ServiceDiscoveryClientImpl() {
+}
+
+scoped_ptr<ServiceWatcher> ServiceDiscoveryClientImpl::CreateServiceWatcher(
+    const std::string& service_type,
+    const ServiceWatcher::UpdatedCallback& callback) {
+  return scoped_ptr<ServiceWatcher>(new ServiceWatcherImpl(
+      service_type, callback, mdns_client_));
+}
+
+scoped_ptr<ServiceResolver> ServiceDiscoveryClientImpl::CreateServiceResolver(
+    const std::string& service_name,
+    const ServiceResolver::ResolveCompleteCallback& callback) {
+  return scoped_ptr<ServiceResolver>(new ServiceResolverImpl(
+      service_name, callback, mdns_client_));
+}
+
+scoped_ptr<LocalDomainResolver>
+ServiceDiscoveryClientImpl::CreateLocalDomainResolver(
+      const std::string& domain,
+      net::AddressFamily address_family,
+      const LocalDomainResolver::IPAddressCallback& callback) {
+  return scoped_ptr<LocalDomainResolver>(new LocalDomainResolverImpl(
+      domain, address_family, callback, mdns_client_));
+}
+
+ServiceWatcherImpl::ServiceWatcherImpl(
+    const std::string& service_type,
+    const ServiceWatcher::UpdatedCallback& callback,
+    net::MDnsClient* mdns_client)
+    : service_type_(service_type), callback_(callback), started_(false),
+      actively_refresh_services_(false), mdns_client_(mdns_client) {
+}
+
+void ServiceWatcherImpl::Start() {
+  DCHECK(!started_);
+  listener_ = mdns_client_->CreateListener(
+      net::dns_protocol::kTypePTR, service_type_, this);
+  started_ = listener_->Start();
+  if (started_)
+    ReadCachedServices();
+}
+
+ServiceWatcherImpl::~ServiceWatcherImpl() {
+}
+
+void ServiceWatcherImpl::DiscoverNewServices(bool force_update) {
+  DCHECK(started_);
+  if (force_update)
+    services_.clear();
+  SendQuery(kInitialRequeryTimeSeconds, force_update);
+}
+
+void ServiceWatcherImpl::SetActivelyRefreshServices(
+    bool actively_refresh_services) {
+  DCHECK(started_);
+  actively_refresh_services_ = actively_refresh_services;
+
+  for (ServiceListenersMap::iterator i = services_.begin();
+       i != services_.end(); i++) {
+    i->second->SetActiveRefresh(actively_refresh_services);
+  }
+}
+
+void ServiceWatcherImpl::ReadCachedServices() {
+  DCHECK(started_);
+  CreateTransaction(false /*network*/, true /*cache*/, false /*force refresh*/,
+                    &transaction_cache_);
+}
+
+bool ServiceWatcherImpl::CreateTransaction(
+    bool network, bool cache, bool force_refresh,
+    scoped_ptr<net::MDnsTransaction>* transaction) {
+  int transaction_flags = 0;
+  if (network)
+    transaction_flags |= net::MDnsTransaction::QUERY_NETWORK;
+
+  if (cache)
+    transaction_flags |= net::MDnsTransaction::QUERY_CACHE;
+
+  // TODO(noamsml): Add flag for force_refresh when supported.
+
+  if (transaction_flags) {
+    *transaction = mdns_client_->CreateTransaction(
+        net::dns_protocol::kTypePTR, service_type_, transaction_flags,
+        base::Bind(&ServiceWatcherImpl::OnTransactionResponse,
+                   base::Unretained(this), transaction));
+    return (*transaction)->Start();
+  }
+
+  return true;
+}
+
+std::string ServiceWatcherImpl::GetServiceType() const {
+  return listener_->GetName();
+}
+
+void ServiceWatcherImpl::OnRecordUpdate(
+    net::MDnsListener::UpdateType update,
+    const net::RecordParsed* record) {
+  DCHECK(started_);
+  if (record->type() == net::dns_protocol::kTypePTR) {
+    DCHECK(record->name() == GetServiceType());
+    const net::PtrRecordRdata* rdata = record->rdata<net::PtrRecordRdata>();
+
+    switch (update) {
+      case net::MDnsListener::RECORD_ADDED:
+        AddService(rdata->ptrdomain());
+        break;
+      case net::MDnsListener::RECORD_CHANGED:
+        NOTREACHED();
+        break;
+      case net::MDnsListener::RECORD_REMOVED:
+        RemovePTR(rdata->ptrdomain());
+        break;
+    }
+  } else {
+    DCHECK(record->type() == net::dns_protocol::kTypeSRV ||
+           record->type() == net::dns_protocol::kTypeTXT);
+    DCHECK(services_.find(record->name()) != services_.end());
+
+    if (record->type() == net::dns_protocol::kTypeSRV) {
+      if (update == net::MDnsListener::RECORD_REMOVED) {
+        RemoveSRV(record->name());
+      } else if (update == net::MDnsListener::RECORD_ADDED) {
+        AddSRV(record->name());
+      }
+    }
+
+    // If this is the first time we see an SRV record, do not send
+    // an UPDATE_CHANGED.
+    if (record->type() != net::dns_protocol::kTypeSRV ||
+        update != net::MDnsListener::RECORD_ADDED) {
+      DeferUpdate(UPDATE_CHANGED, record->name());
+    }
+  }
+}
+
+void ServiceWatcherImpl::OnCachePurged() {
+  // Not yet implemented.
+}
+
+void ServiceWatcherImpl::OnTransactionResponse(
+    scoped_ptr<net::MDnsTransaction>* transaction,
+    net::MDnsTransaction::Result result,
+    const net::RecordParsed* record) {
+  DCHECK(started_);
+  if (result == net::MDnsTransaction::RESULT_RECORD) {
+    const net::PtrRecordRdata* rdata = record->rdata<net::PtrRecordRdata>();
+    DCHECK(rdata);
+    AddService(rdata->ptrdomain());
+  } else if (result == net::MDnsTransaction::RESULT_DONE) {
+    transaction->reset();
+  }
+
+  // Do nothing for NSEC records. It is an error for hosts to broadcast an NSEC
+  // record for PTR records on any name.
+}
+
+ServiceWatcherImpl::ServiceListeners::ServiceListeners(
+    const std::string& service_name,
+    ServiceWatcherImpl* watcher,
+    net::MDnsClient* mdns_client)
+    : service_name_(service_name), mdns_client_(mdns_client),
+      update_pending_(false), has_ptr_(true), has_srv_(false) {
+  srv_listener_ = mdns_client->CreateListener(
+      net::dns_protocol::kTypeSRV, service_name, watcher);
+  txt_listener_ = mdns_client->CreateListener(
+      net::dns_protocol::kTypeTXT, service_name, watcher);
+}
+
+ServiceWatcherImpl::ServiceListeners::~ServiceListeners() {
+}
+
+bool ServiceWatcherImpl::ServiceListeners::Start() {
+  if (!srv_listener_->Start())
+    return false;
+  return txt_listener_->Start();
+}
+
+void ServiceWatcherImpl::ServiceListeners::SetActiveRefresh(
+    bool active_refresh) {
+  srv_listener_->SetActiveRefresh(active_refresh);
+
+  if (active_refresh && !has_srv_) {
+    DCHECK(has_ptr_);
+    srv_transaction_ = mdns_client_->CreateTransaction(
+        net::dns_protocol::kTypeSRV, service_name_,
+        net::MDnsTransaction::SINGLE_RESULT |
+        net::MDnsTransaction::QUERY_CACHE | net::MDnsTransaction::QUERY_NETWORK,
+        base::Bind(&ServiceWatcherImpl::ServiceListeners::OnSRVRecord,
+                   base::Unretained(this)));
+    srv_transaction_->Start();
+  } else if (!active_refresh) {
+    srv_transaction_.reset();
+  }
+}
+
+void ServiceWatcherImpl::ServiceListeners::OnSRVRecord(
+    net::MDnsTransaction::Result result,
+    const net::RecordParsed* record) {
+  set_has_srv(record != NULL);
+}
+
+void ServiceWatcherImpl::ServiceListeners::set_has_srv(bool has_srv) {
+  has_srv_ = has_srv;
+
+  srv_transaction_.reset();
+}
+
+void ServiceWatcherImpl::AddService(const std::string& service) {
+  DCHECK(started_);
+  std::pair<ServiceListenersMap::iterator, bool> found = services_.insert(
+      make_pair(service, linked_ptr<ServiceListeners>(NULL)));
+
+  if (found.second) {  // Newly inserted.
+    found.first->second = linked_ptr<ServiceListeners>(
+        new ServiceListeners(service, this, mdns_client_));
+    bool success = found.first->second->Start();
+    found.first->second->SetActiveRefresh(actively_refresh_services_);
+    DeferUpdate(UPDATE_ADDED, service);
+
+    DCHECK(success);
+  }
+
+  found.first->second->set_has_ptr(true);
+}
+
+void ServiceWatcherImpl::AddSRV(const std::string& service) {
+  DCHECK(started_);
+
+  ServiceListenersMap::iterator found = services_.find(service);
+  if (found != services_.end()) {
+    found->second->set_has_srv(true);
+  }
+}
+
+void ServiceWatcherImpl::DeferUpdate(ServiceWatcher::UpdateType update_type,
+                                     const std::string& service_name) {
+  ServiceListenersMap::iterator found = services_.find(service_name);
+
+  if (found != services_.end() && !found->second->update_pending()) {
+    found->second->set_update_pending(true);
+    base::MessageLoop::current()->PostTask(
+        FROM_HERE,
+        base::Bind(&ServiceWatcherImpl::DeliverDeferredUpdate, AsWeakPtr(),
+                   update_type, service_name));
+  }
+}
+
+void ServiceWatcherImpl::DeliverDeferredUpdate(
+    ServiceWatcher::UpdateType update_type, const std::string& service_name) {
+  ServiceListenersMap::iterator found = services_.find(service_name);
+
+  if (found != services_.end()) {
+    found->second->set_update_pending(false);
+    if (!callback_.is_null())
+      callback_.Run(update_type, service_name);
+  }
+}
+
+void ServiceWatcherImpl::RemovePTR(const std::string& service) {
+  DCHECK(started_);
+
+  ServiceListenersMap::iterator found = services_.find(service);
+  if (found != services_.end()) {
+    found->second->set_has_ptr(false);
+
+    if (!found->second->has_ptr_or_srv()) {
+      services_.erase(found);
+      if (!callback_.is_null())
+        callback_.Run(UPDATE_REMOVED, service);
+    }
+  }
+}
+
+void ServiceWatcherImpl::RemoveSRV(const std::string& service) {
+  DCHECK(started_);
+
+  ServiceListenersMap::iterator found = services_.find(service);
+  if (found != services_.end()) {
+    found->second->set_has_srv(false);
+
+    if (!found->second->has_ptr_or_srv()) {
+      services_.erase(found);
+      if (!callback_.is_null())
+        callback_.Run(UPDATE_REMOVED, service);
+    }
+  }
+}
+
+void ServiceWatcherImpl::OnNsecRecord(const std::string& name,
+                                      unsigned rrtype) {
+  // Do nothing. It is an error for hosts to broadcast an NSEC record for PTR
+  // on any name.
+}
+
+void ServiceWatcherImpl::ScheduleQuery(int timeout_seconds) {
+  if (timeout_seconds <= kMaxRequeryTimeSeconds) {
+    base::MessageLoop::current()->PostDelayedTask(
+        FROM_HERE,
+        base::Bind(&ServiceWatcherImpl::SendQuery,
+                   AsWeakPtr(),
+                   timeout_seconds * 2 /*next_timeout_seconds*/,
+                   false /*force_update*/),
+        base::TimeDelta::FromSeconds(timeout_seconds));
+  }
+}
+
+void ServiceWatcherImpl::SendQuery(int next_timeout_seconds,
+                                   bool force_update) {
+  CreateTransaction(true /*network*/, false /*cache*/, force_update,
+                    &transaction_network_);
+  ScheduleQuery(next_timeout_seconds);
+}
+
+ServiceResolverImpl::ServiceResolverImpl(
+    const std::string& service_name,
+    const ResolveCompleteCallback& callback,
+    net::MDnsClient* mdns_client)
+    : service_name_(service_name), callback_(callback),
+      metadata_resolved_(false), address_resolved_(false),
+      mdns_client_(mdns_client) {
+}
+
+void ServiceResolverImpl::StartResolving() {
+  address_resolved_ = false;
+  metadata_resolved_ = false;
+  service_staging_ = ServiceDescription();
+  service_staging_.service_name = service_name_;
+
+  if (!CreateTxtTransaction() || !CreateSrvTransaction()) {
+    ServiceNotFound(ServiceResolver::STATUS_REQUEST_TIMEOUT);
+  }
+}
+
+ServiceResolverImpl::~ServiceResolverImpl() {
+}
+
+bool ServiceResolverImpl::CreateTxtTransaction() {
+  txt_transaction_ = mdns_client_->CreateTransaction(
+      net::dns_protocol::kTypeTXT, service_name_,
+      net::MDnsTransaction::SINGLE_RESULT | net::MDnsTransaction::QUERY_CACHE |
+      net::MDnsTransaction::QUERY_NETWORK,
+      base::Bind(&ServiceResolverImpl::TxtRecordTransactionResponse,
+                 AsWeakPtr()));
+  return txt_transaction_->Start();
+}
+
+// TODO(noamsml): quick-resolve for AAAA records.  Since A records tend to be in
+void ServiceResolverImpl::CreateATransaction() {
+  a_transaction_ = mdns_client_->CreateTransaction(
+      net::dns_protocol::kTypeA,
+      service_staging_.address.host(),
+      net::MDnsTransaction::SINGLE_RESULT | net::MDnsTransaction::QUERY_CACHE,
+      base::Bind(&ServiceResolverImpl::ARecordTransactionResponse,
+                 AsWeakPtr()));
+  a_transaction_->Start();
+}
+
+bool ServiceResolverImpl::CreateSrvTransaction() {
+  srv_transaction_ = mdns_client_->CreateTransaction(
+      net::dns_protocol::kTypeSRV, service_name_,
+      net::MDnsTransaction::SINGLE_RESULT | net::MDnsTransaction::QUERY_CACHE |
+      net::MDnsTransaction::QUERY_NETWORK,
+      base::Bind(&ServiceResolverImpl::SrvRecordTransactionResponse,
+                 AsWeakPtr()));
+  return srv_transaction_->Start();
+}
+
+std::string ServiceResolverImpl::GetName() const {
+  return service_name_;
+}
+
+void ServiceResolverImpl::SrvRecordTransactionResponse(
+    net::MDnsTransaction::Result status, const net::RecordParsed* record) {
+  srv_transaction_.reset();
+  if (status == net::MDnsTransaction::RESULT_RECORD) {
+    DCHECK(record);
+    service_staging_.address = RecordToAddress(record);
+    service_staging_.last_seen = record->time_created();
+    CreateATransaction();
+  } else {
+    ServiceNotFound(MDnsStatusToRequestStatus(status));
+  }
+}
+
+void ServiceResolverImpl::TxtRecordTransactionResponse(
+    net::MDnsTransaction::Result status, const net::RecordParsed* record) {
+  txt_transaction_.reset();
+  if (status == net::MDnsTransaction::RESULT_RECORD) {
+    DCHECK(record);
+    service_staging_.metadata = RecordToMetadata(record);
+  } else {
+    service_staging_.metadata = std::vector<std::string>();
+  }
+
+  metadata_resolved_ = true;
+  AlertCallbackIfReady();
+}
+
+void ServiceResolverImpl::ARecordTransactionResponse(
+    net::MDnsTransaction::Result status, const net::RecordParsed* record) {
+  a_transaction_.reset();
+
+  if (status == net::MDnsTransaction::RESULT_RECORD) {
+    DCHECK(record);
+    service_staging_.ip_address = RecordToIPAddress(record);
+  } else {
+    service_staging_.ip_address = net::IPAddressNumber();
+  }
+
+  address_resolved_ = true;
+  AlertCallbackIfReady();
+}
+
+void ServiceResolverImpl::AlertCallbackIfReady() {
+  if (metadata_resolved_ && address_resolved_) {
+    txt_transaction_.reset();
+    srv_transaction_.reset();
+    a_transaction_.reset();
+    if (!callback_.is_null())
+      callback_.Run(STATUS_SUCCESS, service_staging_);
+  }
+}
+
+void ServiceResolverImpl::ServiceNotFound(
+    ServiceResolver::RequestStatus status) {
+  txt_transaction_.reset();
+  srv_transaction_.reset();
+  a_transaction_.reset();
+  if (!callback_.is_null())
+    callback_.Run(status, ServiceDescription());
+}
+
+ServiceResolver::RequestStatus ServiceResolverImpl::MDnsStatusToRequestStatus(
+    net::MDnsTransaction::Result status) const {
+  switch (status) {
+    case net::MDnsTransaction::RESULT_RECORD:
+      return ServiceResolver::STATUS_SUCCESS;
+    case net::MDnsTransaction::RESULT_NO_RESULTS:
+      return ServiceResolver::STATUS_REQUEST_TIMEOUT;
+    case net::MDnsTransaction::RESULT_NSEC:
+      return ServiceResolver::STATUS_KNOWN_NONEXISTENT;
+    case net::MDnsTransaction::RESULT_DONE:  // Pass through.
+    default:
+      NOTREACHED();
+      return ServiceResolver::STATUS_REQUEST_TIMEOUT;
+  }
+}
+
+const std::vector<std::string>& ServiceResolverImpl::RecordToMetadata(
+    const net::RecordParsed* record) const {
+  DCHECK(record->type() == net::dns_protocol::kTypeTXT);
+  const net::TxtRecordRdata* txt_rdata = record->rdata<net::TxtRecordRdata>();
+  DCHECK(txt_rdata);
+  return txt_rdata->texts();
+}
+
+net::HostPortPair ServiceResolverImpl::RecordToAddress(
+    const net::RecordParsed* record) const {
+  DCHECK(record->type() == net::dns_protocol::kTypeSRV);
+  const net::SrvRecordRdata* srv_rdata = record->rdata<net::SrvRecordRdata>();
+  DCHECK(srv_rdata);
+  return net::HostPortPair(srv_rdata->target(), srv_rdata->port());
+}
+
+const net::IPAddressNumber& ServiceResolverImpl::RecordToIPAddress(
+    const net::RecordParsed* record) const {
+  DCHECK(record->type() == net::dns_protocol::kTypeA);
+  const net::ARecordRdata* a_rdata = record->rdata<net::ARecordRdata>();
+  DCHECK(a_rdata);
+  return a_rdata->address();
+}
+
+LocalDomainResolverImpl::LocalDomainResolverImpl(
+    const std::string& domain,
+    net::AddressFamily address_family,
+    const IPAddressCallback& callback,
+    net::MDnsClient* mdns_client)
+    : domain_(domain), address_family_(address_family), callback_(callback),
+      transactions_finished_(0), mdns_client_(mdns_client) {
+}
+
+LocalDomainResolverImpl::~LocalDomainResolverImpl() {
+  timeout_callback_.Cancel();
+}
+
+void LocalDomainResolverImpl::Start() {
+  if (address_family_ == net::ADDRESS_FAMILY_IPV4 ||
+      address_family_ == net::ADDRESS_FAMILY_UNSPECIFIED) {
+    transaction_a_ = CreateTransaction(net::dns_protocol::kTypeA);
+    transaction_a_->Start();
+  }
+
+  if (address_family_ == net::ADDRESS_FAMILY_IPV6 ||
+      address_family_ == net::ADDRESS_FAMILY_UNSPECIFIED) {
+    transaction_aaaa_ = CreateTransaction(net::dns_protocol::kTypeAAAA);
+    transaction_aaaa_->Start();
+  }
+}
+
+scoped_ptr<net::MDnsTransaction> LocalDomainResolverImpl::CreateTransaction(
+    uint16 type) {
+  return mdns_client_->CreateTransaction(
+      type, domain_, net::MDnsTransaction::SINGLE_RESULT |
+                     net::MDnsTransaction::QUERY_CACHE |
+                     net::MDnsTransaction::QUERY_NETWORK,
+      base::Bind(&LocalDomainResolverImpl::OnTransactionComplete,
+                 base::Unretained(this)));
+}
+
+void LocalDomainResolverImpl::OnTransactionComplete(
+    net::MDnsTransaction::Result result, const net::RecordParsed* record) {
+  transactions_finished_++;
+
+  if (result == net::MDnsTransaction::RESULT_RECORD) {
+    if (record->type() == net::dns_protocol::kTypeA) {
+      const net::ARecordRdata* rdata = record->rdata<net::ARecordRdata>();
+      address_ipv4_ = rdata->address();
+    } else {
+      DCHECK_EQ(net::dns_protocol::kTypeAAAA, record->type());
+      const net::AAAARecordRdata* rdata = record->rdata<net::AAAARecordRdata>();
+      address_ipv6_ = rdata->address();
+    }
+  }
+
+  if (transactions_finished_ == 1 &&
+      address_family_ == net::ADDRESS_FAMILY_UNSPECIFIED) {
+    timeout_callback_.Reset(base::Bind(
+        &LocalDomainResolverImpl::SendResolvedAddresses,
+        base::Unretained(this)));
+
+    base::MessageLoop::current()->PostDelayedTask(
+        FROM_HERE,
+        timeout_callback_.callback(),
+        base::TimeDelta::FromMilliseconds(kLocalDomainSecondAddressTimeoutMs));
+  } else if (transactions_finished_ == 2
+      || address_family_ != net::ADDRESS_FAMILY_UNSPECIFIED) {
+    SendResolvedAddresses();
+  }
+}
+
+bool LocalDomainResolverImpl::IsSuccess() {
+  return !address_ipv4_.empty() || !address_ipv6_.empty();
+}
+
+void LocalDomainResolverImpl::SendResolvedAddresses() {
+  transaction_a_.reset();
+  transaction_aaaa_.reset();
+  timeout_callback_.Cancel();
+  callback_.Run(IsSuccess(), address_ipv4_, address_ipv6_);
+}
+
+}  // namespace local_discovery