blob: a61a4a3ab22a867fba5d272f7d9961b12776bf23 [file] [log] [blame]
// Copyright (c) 2012 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 "device/geolocation/location_arbitrator_impl.h"
#include <map>
#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/memory/ptr_util.h"
#include "build/build_config.h"
#include "device/geolocation/access_token_store.h"
#include "device/geolocation/geolocation_delegate.h"
#include "device/geolocation/network_location_provider.h"
#include "url/gurl.h"
namespace device {
namespace {
const char* kDefaultNetworkProviderUrl =
"https://www.googleapis.com/geolocation/v1/geolocate";
} // namespace
// To avoid oscillations, set this to twice the expected update interval of a
// a GPS-type location provider (in case it misses a beat) plus a little.
const int64_t LocationArbitratorImpl::kFixStaleTimeoutMilliseconds =
11 * base::Time::kMillisecondsPerSecond;
LocationArbitratorImpl::LocationArbitratorImpl(
const LocationUpdateCallback& callback,
GeolocationDelegate* delegate)
: delegate_(delegate),
arbitrator_update_callback_(callback),
provider_update_callback_(
base::Bind(&LocationArbitratorImpl::OnLocationUpdate,
base::Unretained(this))),
position_provider_(nullptr),
is_permission_granted_(false),
is_running_(false) {}
LocationArbitratorImpl::~LocationArbitratorImpl() {}
GURL LocationArbitratorImpl::DefaultNetworkProviderURL() {
return GURL(kDefaultNetworkProviderUrl);
}
void LocationArbitratorImpl::OnPermissionGranted() {
is_permission_granted_ = true;
for (const auto& provider : providers_)
provider->OnPermissionGranted();
}
void LocationArbitratorImpl::StartProviders(bool enable_high_accuracy) {
// Stash options as OnAccessTokenStoresLoaded has not yet been called.
is_running_ = true;
enable_high_accuracy_ = enable_high_accuracy;
if (providers_.empty()) {
RegisterSystemProvider();
const scoped_refptr<AccessTokenStore> access_token_store =
GetAccessTokenStore();
if (access_token_store && delegate_->UseNetworkLocationProviders()) {
DCHECK(DefaultNetworkProviderURL().is_valid());
token_store_callback_.Reset(
base::Bind(&LocationArbitratorImpl::OnAccessTokenStoresLoaded,
base::Unretained(this)));
access_token_store->LoadAccessTokens(token_store_callback_.callback());
return;
}
}
DoStartProviders();
}
void LocationArbitratorImpl::DoStartProviders() {
if (providers_.empty()) {
// If no providers are available, we report an error to avoid
// callers waiting indefinitely for a reply.
Geoposition position;
position.error_code = Geoposition::ERROR_CODE_PERMISSION_DENIED;
arbitrator_update_callback_.Run(position);
return;
}
for (const auto& provider : providers_)
provider->StartProvider(enable_high_accuracy_);
}
void LocationArbitratorImpl::StopProviders() {
// Reset the reference location state (provider+position)
// so that future starts use fresh locations from
// the newly constructed providers.
position_provider_ = nullptr;
position_ = Geoposition();
providers_.clear();
is_running_ = false;
}
void LocationArbitratorImpl::OnAccessTokenStoresLoaded(
AccessTokenStore::AccessTokenMap access_token_map,
const scoped_refptr<net::URLRequestContextGetter>& context_getter) {
// If there are no access tokens, boot strap it with the default server URL.
if (access_token_map.empty())
access_token_map[DefaultNetworkProviderURL()];
for (const auto& entry : access_token_map) {
RegisterProvider(NewNetworkLocationProvider(
GetAccessTokenStore(), context_getter, entry.first, entry.second));
}
DoStartProviders();
}
void LocationArbitratorImpl::RegisterProvider(
std::unique_ptr<LocationProvider> provider) {
if (!provider)
return;
provider->SetUpdateCallback(provider_update_callback_);
if (is_permission_granted_)
provider->OnPermissionGranted();
providers_.push_back(std::move(provider));
}
void LocationArbitratorImpl::RegisterSystemProvider() {
std::unique_ptr<LocationProvider> provider =
delegate_->OverrideSystemLocationProvider();
if (!provider)
provider = NewSystemLocationProvider();
RegisterProvider(std::move(provider));
}
void LocationArbitratorImpl::OnLocationUpdate(const LocationProvider* provider,
const Geoposition& new_position) {
DCHECK(new_position.Validate() ||
new_position.error_code != Geoposition::ERROR_CODE_NONE);
if (!IsNewPositionBetter(position_, new_position,
provider == position_provider_))
return;
position_provider_ = provider;
position_ = new_position;
arbitrator_update_callback_.Run(position_);
}
scoped_refptr<AccessTokenStore> LocationArbitratorImpl::NewAccessTokenStore() {
return delegate_->CreateAccessTokenStore();
}
scoped_refptr<AccessTokenStore> LocationArbitratorImpl::GetAccessTokenStore() {
if (!access_token_store_)
access_token_store_ = NewAccessTokenStore();
return access_token_store_;
}
std::unique_ptr<LocationProvider>
LocationArbitratorImpl::NewNetworkLocationProvider(
const scoped_refptr<AccessTokenStore>& access_token_store,
const scoped_refptr<net::URLRequestContextGetter>& context,
const GURL& url,
const base::string16& access_token) {
#if defined(OS_ANDROID)
// Android uses its own SystemLocationProvider.
return nullptr;
#else
return base::WrapUnique(new NetworkLocationProvider(
access_token_store, context, url, access_token));
#endif
}
std::unique_ptr<LocationProvider>
LocationArbitratorImpl::NewSystemLocationProvider() {
#if defined(OS_WIN) || defined(OS_MACOSX) || defined(OS_LINUX)
return nullptr;
#else
return device::NewSystemLocationProvider();
#endif
}
base::Time LocationArbitratorImpl::GetTimeNow() const {
return base::Time::Now();
}
bool LocationArbitratorImpl::IsNewPositionBetter(
const Geoposition& old_position,
const Geoposition& new_position,
bool from_same_provider) const {
// Updates location_info if it's better than what we currently have,
// or if it's a newer update from the same provider.
if (!old_position.Validate()) {
// Older location wasn't locked.
return true;
}
if (new_position.Validate()) {
// New location is locked, let's check if it's any better.
if (old_position.accuracy >= new_position.accuracy) {
// Accuracy is better.
return true;
} else if (from_same_provider) {
// Same provider, fresher location.
return true;
} else if ((GetTimeNow() - old_position.timestamp).InMilliseconds() >
kFixStaleTimeoutMilliseconds) {
// Existing fix is stale.
return true;
}
}
return false;
}
bool LocationArbitratorImpl::HasPermissionBeenGranted() const {
return is_permission_granted_;
}
} // namespace device