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 #ifndef vm_List_inl_h
8 #define vm_List_inl_h
9
10 #include "vm/List.h"
11
12 #include "mozilla/Assertions.h" // MOZ_ASSERT
13
14 #include <stdint.h> // uint32_t
15
16 #include "js/RootingAPI.h" // JS::Handle, JS::Rooted
17 #include "js/Value.h" // JS::Value, JS::ObjectValue
18 #include "vm/JSContext.h" // JSContext
19 #include "vm/NativeObject.h" // js::NativeObject
20
21 #include "vm/Compartment-inl.h" // JS::Compartment::wrap
22 #include "vm/JSObject-inl.h" // js::NewObjectWithGivenProto
23 #include "vm/NativeObject-inl.h" // js::NativeObject::*
24 #include "vm/Realm-inl.h" // js::AutoRealm
25
create(JSContext * cx)26 inline /* static */ js::ListObject* js::ListObject::create(JSContext* cx) {
27 return NewObjectWithGivenProto<ListObject>(cx, nullptr);
28 }
29
append(JSContext * cx,JS::Handle<JS::Value> value)30 inline bool js::ListObject::append(JSContext* cx, JS::Handle<JS::Value> value) {
31 uint32_t len = length();
32
33 if (!ensureElements(cx, len + 1)) {
34 return false;
35 }
36
37 ensureDenseInitializedLength(len, 1);
38 setDenseElement(len, value);
39 return true;
40 }
41
appendValueAndSize(JSContext * cx,JS::Handle<JS::Value> value,double size)42 inline bool js::ListObject::appendValueAndSize(JSContext* cx,
43 JS::Handle<JS::Value> value,
44 double size) {
45 uint32_t len = length();
46
47 if (!ensureElements(cx, len + 2)) {
48 return false;
49 }
50
51 ensureDenseInitializedLength(len, 2);
52 setDenseElement(len, value);
53 setDenseElement(len + 1, JS::DoubleValue(size));
54 return true;
55 }
56
popFirst(JSContext * cx)57 inline JS::Value js::ListObject::popFirst(JSContext* cx) {
58 uint32_t len = length();
59 MOZ_ASSERT(len > 0);
60
61 JS::Value entry = get(0);
62 if (!tryShiftDenseElements(1)) {
63 moveDenseElements(0, 1, len - 1);
64 setDenseInitializedLength(len - 1);
65 shrinkElements(cx, len - 1);
66 }
67
68 MOZ_ASSERT(length() == len - 1);
69 return entry;
70 }
71
popFirstPair(JSContext * cx)72 inline void js::ListObject::popFirstPair(JSContext* cx) {
73 uint32_t len = length();
74 MOZ_ASSERT(len > 0);
75 MOZ_ASSERT((len % 2) == 0);
76
77 if (!tryShiftDenseElements(2)) {
78 moveDenseElements(0, 2, len - 2);
79 setDenseInitializedLength(len - 2);
80 shrinkElements(cx, len - 2);
81 }
82
83 MOZ_ASSERT(length() == len - 2);
84 }
85
86 template <class T>
popFirstAs(JSContext * cx)87 inline T& js::ListObject::popFirstAs(JSContext* cx) {
88 return popFirst(cx).toObject().as<T>();
89 }
90
91 namespace js {
92
93 /**
94 * Stores an empty ListObject in the given fixed slot of |obj|.
95 */
StoreNewListInFixedSlot(JSContext * cx,JS::Handle<NativeObject * > obj,uint32_t slot)96 [[nodiscard]] inline bool StoreNewListInFixedSlot(JSContext* cx,
97 JS::Handle<NativeObject*> obj,
98 uint32_t slot) {
99 AutoRealm ar(cx, obj);
100 ListObject* list = ListObject::create(cx);
101 if (!list) {
102 return false;
103 }
104
105 obj->setFixedSlot(slot, JS::ObjectValue(*list));
106 return true;
107 }
108
109 /**
110 * Given an object |obj| whose fixed slot |slot| contains a ListObject, append
111 * |toAppend| to that list.
112 */
AppendToListInFixedSlot(JSContext * cx,JS::Handle<NativeObject * > obj,uint32_t slot,JS::Handle<JSObject * > toAppend)113 [[nodiscard]] inline bool AppendToListInFixedSlot(
114 JSContext* cx, JS::Handle<NativeObject*> obj, uint32_t slot,
115 JS::Handle<JSObject*> toAppend) {
116 JS::Rooted<ListObject*> list(
117 cx, &obj->getFixedSlot(slot).toObject().as<ListObject>());
118
119 AutoRealm ar(cx, list);
120 JS::Rooted<JS::Value> val(cx, JS::ObjectValue(*toAppend));
121 if (!cx->compartment()->wrap(cx, &val)) {
122 return false;
123 }
124 return list->append(cx, val);
125 }
126
127 } // namespace js
128
129 #endif // vm_List_inl_h
130