dom/xslt/base/txStack.h@97036ab72558
dom/xslt/base/txStack.h
Tue, 06 Jan 2015 21:39:09 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Tue, 06 Jan 2015 21:39:09 +0100
- branch
- TOR_BUG_9701
- changeset 8
- 97036ab72558
- permissions
- -rw-r--r--
Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.
1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
6 #ifndef txStack_h___
7 #define txStack_h___
9 #include "nsTArray.h"
11 class txStack : private nsTArray<void*>
12 {
13 public:
14 /**
15 * Returns the specified object from the top of this stack,
16 * without removing it from the stack.
17 *
18 * @return a pointer to the object that is the top of this stack.
19 */
20 inline void* peek()
21 {
22 NS_ASSERTION(!isEmpty(), "peeking at empty stack");
23 return !isEmpty() ? ElementAt(Length() - 1) : nullptr;
24 }
26 /**
27 * Adds the specified object to the top of this stack.
28 *
29 * @param obj a pointer to the object that is to be added to the
30 * top of this stack.
31 */
32 inline nsresult push(void* aObject)
33 {
34 return AppendElement(aObject) ? NS_OK : NS_ERROR_OUT_OF_MEMORY;
35 }
37 /**
38 * Removes and returns the specified object from the top of this
39 * stack.
40 *
41 * @return a pointer to the object that was the top of this stack.
42 */
43 inline void* pop()
44 {
45 void* object = nullptr;
46 NS_ASSERTION(!isEmpty(), "popping from empty stack");
47 if (!isEmpty())
48 {
49 const uint32_t count = Length() - 1;
50 object = ElementAt(count);
51 RemoveElementAt(count);
52 }
53 return object;
54 }
56 /**
57 * Returns true if there are no objects in the stack.
58 *
59 * @return true if there are no objects in the stack.
60 */
61 inline bool isEmpty()
62 {
63 return IsEmpty();
64 }
66 /**
67 * Returns the number of elements in the Stack.
68 *
69 * @return the number of elements in the Stack.
70 */
71 inline int32_t size()
72 {
73 return Length();
74 }
76 private:
77 friend class txStackIterator;
78 };
80 class txStackIterator
81 {
82 public:
83 /**
84 * Creates an iterator for the given stack.
85 *
86 * @param aStack the stack to create an iterator for.
87 */
88 inline
89 txStackIterator(txStack* aStack) : mStack(aStack),
90 mPosition(0)
91 {
92 }
94 /**
95 * Returns true if there is more objects on the stack.
96 *
97 * @return .
98 */
99 inline bool hasNext()
100 {
101 return (mPosition < mStack->Length());
102 }
104 /**
105 * Returns the next object pointer from the stack.
106 *
107 * @return .
108 */
109 inline void* next()
110 {
111 if (mPosition == mStack->Length()) {
112 return nullptr;
113 }
114 return mStack->ElementAt(mPosition++);
115 }
117 private:
118 txStack* mStack;
119 uint32_t mPosition;
120 };
122 #endif /* txStack_h___ */
