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 /* representation of CSSRuleList for stylo */
8 
9 #include "mozilla/ServoCSSRuleList.h"
10 
11 #include "mozilla/IntegerRange.h"
12 #include "mozilla/ServoBindings.h"
13 #include "mozilla/ServoDocumentRule.h"
14 #include "mozilla/ServoImportRule.h"
15 #include "mozilla/ServoFontFeatureValuesRule.h"
16 #include "mozilla/ServoKeyframesRule.h"
17 #include "mozilla/ServoMediaRule.h"
18 #include "mozilla/ServoNamespaceRule.h"
19 #include "mozilla/ServoPageRule.h"
20 #include "mozilla/ServoStyleRule.h"
21 #include "mozilla/ServoStyleSheet.h"
22 #include "mozilla/ServoSupportsRule.h"
23 #include "nsCSSCounterStyleRule.h"
24 #include "nsCSSFontFaceRule.h"
25 
26 using namespace mozilla::dom;
27 
28 namespace mozilla {
29 
ServoCSSRuleList(already_AddRefed<ServoCssRules> aRawRules,ServoStyleSheet * aDirectOwnerStyleSheet)30 ServoCSSRuleList::ServoCSSRuleList(already_AddRefed<ServoCssRules> aRawRules,
31                                    ServoStyleSheet* aDirectOwnerStyleSheet)
32     : mStyleSheet(aDirectOwnerStyleSheet), mRawRules(aRawRules) {
33   Servo_CssRules_ListTypes(mRawRules, &mRules);
34 }
35 
36 // QueryInterface implementation for ServoCSSRuleList
37 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ServoCSSRuleList)
38 NS_INTERFACE_MAP_END_INHERITING(dom::CSSRuleList)
39 
40 NS_IMPL_ADDREF_INHERITED(ServoCSSRuleList, dom::CSSRuleList)
41 NS_IMPL_RELEASE_INHERITED(ServoCSSRuleList, dom::CSSRuleList)
42 
43 NS_IMPL_CYCLE_COLLECTION_CLASS(ServoCSSRuleList)
44 
45 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(ServoCSSRuleList)
46   tmp->DropAllRules();
47 NS_IMPL_CYCLE_COLLECTION_UNLINK_END_INHERITED(dom::CSSRuleList)
48 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(ServoCSSRuleList,
49                                                   dom::CSSRuleList)
__anon0f6ab9ce0102(css::Rule* aRule) 50   tmp->EnumerateInstantiatedRules([&](css::Rule* aRule) {
51     if (!aRule->IsCCLeaf()) {
52       NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mRules[i]");
53       cb.NoteXPCOMChild(aRule);
54       // Note about @font-face and @counter-style rule again, since
55       // there is an indirect owning edge through Servo's struct that
56       // FontFaceRule / CounterStyleRule in Servo owns a Gecko
57       // nsCSSFontFaceRule / nsCSSCounterStyleRule object.
58       auto type = aRule->Type();
59       if (type == CSSRuleBinding::FONT_FACE_RULE ||
60           type == CSSRuleBinding::COUNTER_STYLE_RULE) {
61         NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mRawRules[i]");
62         cb.NoteXPCOMChild(aRule);
63       }
64     }
65   });
66 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
67 
SetParentRule(css::GroupRule * aParentRule)68 void ServoCSSRuleList::SetParentRule(css::GroupRule* aParentRule) {
69   mParentRule = aParentRule;
70   EnumerateInstantiatedRules(
71       [aParentRule](css::Rule* rule) { rule->SetParentRule(aParentRule); });
72 }
73 
SetStyleSheet(StyleSheet * aStyleSheet)74 void ServoCSSRuleList::SetStyleSheet(StyleSheet* aStyleSheet) {
75   mStyleSheet = aStyleSheet ? aStyleSheet->AsServo() : nullptr;
76   EnumerateInstantiatedRules(
77       [this](css::Rule* rule) { rule->SetStyleSheet(mStyleSheet); });
78 }
79 
GetRule(uint32_t aIndex)80 css::Rule* ServoCSSRuleList::GetRule(uint32_t aIndex) {
81   uintptr_t rule = mRules[aIndex];
82   if (rule <= kMaxRuleType) {
83     RefPtr<css::Rule> ruleObj = nullptr;
84     switch (rule) {
85 #define CASE_RULE(const_, name_)                                             \
86   case CSSRuleBinding::const_##_RULE: {                                      \
87     uint32_t line = 0, column = 0;                                           \
88     RefPtr<RawServo##name_##Rule> rule =                                     \
89         Servo_CssRules_Get##name_##RuleAt(mRawRules, aIndex, &line, &column) \
90             .Consume();                                                      \
91     MOZ_ASSERT(rule);                                                        \
92     ruleObj = new Servo##name_##Rule(rule.forget(), line, column);           \
93     break;                                                                   \
94   }
95       CASE_RULE(STYLE, Style)
96       CASE_RULE(KEYFRAMES, Keyframes)
97       CASE_RULE(MEDIA, Media)
98       CASE_RULE(NAMESPACE, Namespace)
99       CASE_RULE(PAGE, Page)
100       CASE_RULE(SUPPORTS, Supports)
101       CASE_RULE(DOCUMENT, Document)
102       CASE_RULE(IMPORT, Import)
103       CASE_RULE(FONT_FEATURE_VALUES, FontFeatureValues)
104 #undef CASE_RULE
105       // For @font-face and @counter-style rules, the function returns
106       // a borrowed Gecko rule object directly, so we don't need to
107       // create anything here. But we still need to have the style sheet
108       // and parent rule set properly.
109       case CSSRuleBinding::FONT_FACE_RULE: {
110         ruleObj = Servo_CssRules_GetFontFaceRuleAt(mRawRules, aIndex);
111         break;
112       }
113       case CSSRuleBinding::COUNTER_STYLE_RULE: {
114         ruleObj = Servo_CssRules_GetCounterStyleRuleAt(mRawRules, aIndex);
115         break;
116       }
117       case CSSRuleBinding::KEYFRAME_RULE:
118         MOZ_ASSERT_UNREACHABLE("keyframe rule cannot be here");
119         return nullptr;
120       default:
121         NS_WARNING("stylo: not implemented yet");
122         return nullptr;
123     }
124     ruleObj->SetStyleSheet(mStyleSheet);
125     ruleObj->SetParentRule(mParentRule);
126     rule = CastToUint(ruleObj.forget().take());
127     mRules[aIndex] = rule;
128   }
129   return CastToPtr(rule);
130 }
131 
IndexedGetter(uint32_t aIndex,bool & aFound)132 css::Rule* ServoCSSRuleList::IndexedGetter(uint32_t aIndex, bool& aFound) {
133   if (aIndex >= mRules.Length()) {
134     aFound = false;
135     return nullptr;
136   }
137   aFound = true;
138   return GetRule(aIndex);
139 }
140 
141 template <typename Func>
EnumerateInstantiatedRules(Func aCallback)142 void ServoCSSRuleList::EnumerateInstantiatedRules(Func aCallback) {
143   for (uintptr_t rule : mRules) {
144     if (rule > kMaxRuleType) {
145       aCallback(CastToPtr(rule));
146     }
147   }
148 }
149 
DropRule(already_AddRefed<css::Rule> aRule)150 static void DropRule(already_AddRefed<css::Rule> aRule) {
151   RefPtr<css::Rule> rule = aRule;
152   rule->SetStyleSheet(nullptr);
153   rule->SetParentRule(nullptr);
154 }
155 
DropAllRules()156 void ServoCSSRuleList::DropAllRules() {
157   EnumerateInstantiatedRules(
158       [](css::Rule* rule) { DropRule(already_AddRefed<css::Rule>(rule)); });
159   mRules.Clear();
160   mRawRules = nullptr;
161 }
162 
DropReference()163 void ServoCSSRuleList::DropReference() {
164   mStyleSheet = nullptr;
165   mParentRule = nullptr;
166   DropAllRules();
167 }
168 
InsertRule(const nsAString & aRule,uint32_t aIndex)169 nsresult ServoCSSRuleList::InsertRule(const nsAString& aRule, uint32_t aIndex) {
170   MOZ_ASSERT(mStyleSheet,
171              "Caller must ensure that "
172              "the list is not unlinked from stylesheet");
173   NS_ConvertUTF16toUTF8 rule(aRule);
174   bool nested = !!mParentRule;
175   css::Loader* loader = nullptr;
176   if (nsIDocument* doc = mStyleSheet->GetAssociatedDocument()) {
177     loader = doc->CSSLoader();
178   }
179   uint16_t type;
180   nsresult rv =
181       Servo_CssRules_InsertRule(mRawRules, mStyleSheet->RawContents(), &rule,
182                                 aIndex, nested, loader, mStyleSheet, &type);
183   if (NS_FAILED(rv)) {
184     return rv;
185   }
186   mRules.InsertElementAt(aIndex, type);
187   return rv;
188 }
189 
DeleteRule(uint32_t aIndex)190 nsresult ServoCSSRuleList::DeleteRule(uint32_t aIndex) {
191   nsresult rv = Servo_CssRules_DeleteRule(mRawRules, aIndex);
192   if (!NS_FAILED(rv)) {
193     uintptr_t rule = mRules[aIndex];
194     if (rule > kMaxRuleType) {
195       DropRule(already_AddRefed<css::Rule>(CastToPtr(rule)));
196     }
197     mRules.RemoveElementAt(aIndex);
198   }
199   return rv;
200 }
201 
GetDOMCSSRuleType(uint32_t aIndex) const202 uint16_t ServoCSSRuleList::GetDOMCSSRuleType(uint32_t aIndex) const {
203   uintptr_t rule = mRules[aIndex];
204   if (rule <= kMaxRuleType) {
205     return rule;
206   }
207   return CastToPtr(rule)->Type();
208 }
209 
~ServoCSSRuleList()210 ServoCSSRuleList::~ServoCSSRuleList() {
211   MOZ_ASSERT(!mStyleSheet, "Backpointer should have been cleared");
212   MOZ_ASSERT(!mParentRule, "Backpointer should have been cleared");
213   DropAllRules();
214 }
215 
216 }  // namespace mozilla
217