1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
3 /* This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6
7 #include "gfxVars.h"
8 #include "gfxVarReceiver.h"
9 #include "mozilla/dom/ContentChild.h"
10
11 namespace mozilla {
12 namespace gfx {
13
14 StaticAutoPtr<gfxVars> gfxVars::sInstance;
15 StaticAutoPtr<nsTArray<gfxVars::VarBase*>> gfxVars::sVarList;
16
17 StaticAutoPtr<nsTArray<GfxVarUpdate>> gGfxVarInitUpdates;
18
SetValuesForInitialize(const nsTArray<GfxVarUpdate> & aInitUpdates)19 void gfxVars::SetValuesForInitialize(
20 const nsTArray<GfxVarUpdate>& aInitUpdates) {
21 // This should only be called once
22 MOZ_RELEASE_ASSERT(!gGfxVarInitUpdates);
23
24 // We expect aInitUpdates to be provided before any other gfxVars operation,
25 // and for sInstance to be null here, but handle the alternative.
26 if (sInstance) {
27 // Apply the updates, the object has been created already
28 for (const auto& varUpdate : aInitUpdates) {
29 ApplyUpdate(varUpdate);
30 }
31 } else {
32 // Save the values for Initialize call
33 gGfxVarInitUpdates = new nsTArray<GfxVarUpdate>(aInitUpdates.Clone());
34 }
35 }
36
Initialize()37 void gfxVars::Initialize() {
38 if (sInstance) {
39 MOZ_RELEASE_ASSERT(
40 !gGfxVarInitUpdates,
41 "Initial updates should not be present after any gfxVars operation");
42 return;
43 }
44
45 // sVarList must be initialized first since it's used in the constructor for
46 // sInstance.
47 sVarList = new nsTArray<gfxVars::VarBase*>();
48 sInstance = new gfxVars;
49
50 // Note the GPU process is not handled here - it cannot send sync
51 // messages, so instead the initial data is pushed down.
52 if (XRE_IsContentProcess()) {
53 MOZ_ASSERT(gGfxVarInitUpdates,
54 "Initial updates should be provided in content process");
55 if (!gGfxVarInitUpdates) {
56 // No provided initial updates, sync-request them from parent.
57 nsTArray<GfxVarUpdate> initUpdates;
58 dom::ContentChild::GetSingleton()->SendGetGfxVars(&initUpdates);
59 gGfxVarInitUpdates = new nsTArray<GfxVarUpdate>(std::move(initUpdates));
60 }
61 for (const auto& varUpdate : *gGfxVarInitUpdates) {
62 ApplyUpdate(varUpdate);
63 }
64 gGfxVarInitUpdates = nullptr;
65 }
66 }
67
68 gfxVars::gfxVars() = default;
69
Shutdown()70 void gfxVars::Shutdown() {
71 sInstance = nullptr;
72 sVarList = nullptr;
73 gGfxVarInitUpdates = nullptr;
74 }
75
76 /* static */
ApplyUpdate(const GfxVarUpdate & aUpdate)77 void gfxVars::ApplyUpdate(const GfxVarUpdate& aUpdate) {
78 // Only subprocesses receive updates and apply them locally.
79 MOZ_ASSERT(!XRE_IsParentProcess());
80 MOZ_DIAGNOSTIC_ASSERT(sVarList || gGfxVarInitUpdates);
81 if (sVarList) {
82 sVarList->ElementAt(aUpdate.index())->SetValue(aUpdate.value());
83 } else if (gGfxVarInitUpdates) {
84 // Too early, we haven't been initialized, so just add to
85 // the array waiting for the initialization...
86 gGfxVarInitUpdates->AppendElement(aUpdate);
87 }
88 }
89
90 /* static */
AddReceiver(gfxVarReceiver * aReceiver)91 void gfxVars::AddReceiver(gfxVarReceiver* aReceiver) {
92 MOZ_ASSERT(NS_IsMainThread());
93
94 // Don't double-add receivers, in case a broken content process sends two
95 // init messages.
96 if (!sInstance->mReceivers.Contains(aReceiver)) {
97 sInstance->mReceivers.AppendElement(aReceiver);
98 }
99 }
100
101 /* static */
RemoveReceiver(gfxVarReceiver * aReceiver)102 void gfxVars::RemoveReceiver(gfxVarReceiver* aReceiver) {
103 MOZ_ASSERT(NS_IsMainThread());
104
105 if (sInstance) {
106 sInstance->mReceivers.RemoveElement(aReceiver);
107 }
108 }
109
110 /* static */
FetchNonDefaultVars()111 nsTArray<GfxVarUpdate> gfxVars::FetchNonDefaultVars() {
112 MOZ_ASSERT(NS_IsMainThread());
113 MOZ_ASSERT(sVarList);
114
115 nsTArray<GfxVarUpdate> updates;
116 for (size_t i = 0; i < sVarList->Length(); i++) {
117 VarBase* var = sVarList->ElementAt(i);
118 if (var->HasDefaultValue()) {
119 continue;
120 }
121
122 GfxVarValue value;
123 var->GetValue(&value);
124
125 updates.AppendElement(GfxVarUpdate(i, value));
126 }
127
128 return updates;
129 }
130
VarBase()131 gfxVars::VarBase::VarBase() {
132 mIndex = gfxVars::sVarList->Length();
133 gfxVars::sVarList->AppendElement(this);
134 }
135
NotifyReceivers(VarBase * aVar)136 void gfxVars::NotifyReceivers(VarBase* aVar) {
137 MOZ_ASSERT(NS_IsMainThread());
138
139 GfxVarValue value;
140 aVar->GetValue(&value);
141
142 GfxVarUpdate update(aVar->Index(), value);
143 for (auto& receiver : mReceivers) {
144 receiver->OnVarChanged(update);
145 }
146 }
147
148 } // namespace gfx
149 } // namespace mozilla
150