gecko-dev/gfx/config/gfxVars.cpp
David Anderson 9e49bc37bb Introduce gfxVars for sharing graphics variables across processes. (bug 1288259 part 2, r=jrmuizel,billm)
--HG--
extra : rebase_source : cbac742f7165a2fbdec3e4d1179c9ed49324579f
2016-08-04 11:33:42 -07:00

126 lines
2.8 KiB
C++

/* -*- Mode: C++; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim: set sts=2 ts=8 sw=2 tw=99 et: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "gfxVars.h"
#include "gfxVarReceiver.h"
#include "mozilla/dom/ContentChild.h"
namespace mozilla {
namespace gfx {
StaticAutoPtr<gfxVars> gfxVars::sInstance;
StaticAutoPtr<nsTArray<gfxVars::VarBase*>> gfxVars::sVarList;
void
gfxVars::Initialize()
{
if (sInstance) {
return;
}
// sVarList must be initialized first since it's used in the constructor for
// sInstance.
sVarList = new nsTArray<gfxVars::VarBase*>();
sInstance = new gfxVars;
// Like Preferences, we want content to synchronously get initial data on
// init. Note the GPU process is not handled here - it cannot send sync
// messages, so instead the initial data is pushed down.
if (XRE_IsContentProcess()) {
InfallibleTArray<GfxVarUpdate> vars;
dom::ContentChild::GetSingleton()->SendGetGfxVars(&vars);
for (const auto& var : vars) {
ApplyUpdate(var);
}
}
}
gfxVars::gfxVars()
{
}
void
gfxVars::Shutdown()
{
sInstance = nullptr;
sVarList = nullptr;
}
/* static */ void
gfxVars::ApplyUpdate(const GfxVarUpdate& aUpdate)
{
// Only subprocesses receive updates and apply them locally.
MOZ_ASSERT(!XRE_IsParentProcess());
sVarList->ElementAt(aUpdate.index())->SetValue(aUpdate.value());
}
/* static */ void
gfxVars::AddReceiver(gfxVarReceiver* aReceiver)
{
MOZ_ASSERT(NS_IsMainThread());
// Don't double-add receivers, in case a broken content process sends two
// init messages.
if (!sInstance->mReceivers.Contains(aReceiver)) {
sInstance->mReceivers.AppendElement(aReceiver);
}
}
/* static */ void
gfxVars::RemoveReceiver(gfxVarReceiver* aReceiver)
{
MOZ_ASSERT(NS_IsMainThread());
if (sInstance) {
sInstance->mReceivers.RemoveElement(aReceiver);
}
}
/* static */ nsTArray<GfxVarUpdate>
gfxVars::FetchNonDefaultVars()
{
MOZ_ASSERT(NS_IsMainThread());
MOZ_ASSERT(sVarList);
nsTArray<GfxVarUpdate> updates;
for (size_t i = 0; i < sVarList->Length(); i++) {
VarBase* var = sVarList->ElementAt(i);
if (var->HasDefaultValue()) {
continue;
}
GfxVarValue value;
var->GetValue(&value);
updates.AppendElement(GfxVarUpdate(i, value));
}
return updates;
}
gfxVars::VarBase::VarBase()
{
mIndex = gfxVars::sVarList->Length();
gfxVars::sVarList->AppendElement(this);
}
void
gfxVars::NotifyReceivers(VarBase* aVar)
{
MOZ_ASSERT(NS_IsMainThread());
GfxVarValue value;
aVar->GetValue(&value);
GfxVarUpdate update(aVar->Index(), value);
for (auto& receiver : mReceivers) {
receiver->OnVarChanged(update);
}
}
} // namespace gfx
} // namespace mozilla