parser/html/nsHtml5AtomTable.h@6474c204b198 (annotated)
parser/html/nsHtml5AtomTable.h
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
| michael@0 | 1 | /* This Source Code Form is subject to the terms of the Mozilla Public |
| michael@0 | 2 | * License, v. 2.0. If a copy of the MPL was not distributed with this |
| michael@0 | 3 | * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ |
| michael@0 | 4 | |
| michael@0 | 5 | #ifndef nsHtml5AtomTable_h |
| michael@0 | 6 | #define nsHtml5AtomTable_h |
| michael@0 | 7 | |
| michael@0 | 8 | #include "nsHashKeys.h" |
| michael@0 | 9 | #include "nsTHashtable.h" |
| michael@0 | 10 | #include "nsAutoPtr.h" |
| michael@0 | 11 | #include "nsIAtom.h" |
| michael@0 | 12 | #include "nsIThread.h" |
| michael@0 | 13 | |
| michael@0 | 14 | class nsHtml5Atom; |
| michael@0 | 15 | |
| michael@0 | 16 | class nsHtml5AtomEntry : public nsStringHashKey |
| michael@0 | 17 | { |
| michael@0 | 18 | public: |
| michael@0 | 19 | nsHtml5AtomEntry(KeyTypePointer aStr); |
| michael@0 | 20 | nsHtml5AtomEntry(const nsHtml5AtomEntry& aOther); |
| michael@0 | 21 | ~nsHtml5AtomEntry(); |
| michael@0 | 22 | inline nsHtml5Atom* GetAtom() |
| michael@0 | 23 | { |
| michael@0 | 24 | return mAtom; |
| michael@0 | 25 | } |
| michael@0 | 26 | private: |
| michael@0 | 27 | nsAutoPtr<nsHtml5Atom> mAtom; |
| michael@0 | 28 | }; |
| michael@0 | 29 | |
| michael@0 | 30 | /** |
| michael@0 | 31 | * nsHtml5AtomTable provides non-locking lookup and creation of atoms for |
| michael@0 | 32 | * nsHtml5Parser or nsHtml5StreamParser. |
| michael@0 | 33 | * |
| michael@0 | 34 | * The hashtable holds dynamically allocated atoms that are private to an |
| michael@0 | 35 | * instance of nsHtml5Parser or nsHtml5StreamParser. (Static atoms are used on |
| michael@0 | 36 | * interned nsHtml5ElementNames and interned nsHtml5AttributeNames. Also, when |
| michael@0 | 37 | * the doctype name is 'html', that identifier needs to be represented as a |
| michael@0 | 38 | * static atom.) |
| michael@0 | 39 | * |
| michael@0 | 40 | * Each instance of nsHtml5Parser has a single instance of nsHtml5AtomTable, |
| michael@0 | 41 | * and each instance of nsHtml5StreamParser has a single instance of |
| michael@0 | 42 | * nsHtml5AtomTable. Dynamic atoms obtained from an nsHtml5AtomTable are valid |
| michael@0 | 43 | * for == comparison with each other or with atoms declared in nsHtml5Atoms |
| michael@0 | 44 | * within the nsHtml5Tokenizer and the nsHtml5TreeBuilder instances owned by |
| michael@0 | 45 | * the same nsHtml5Parser/nsHtml5StreamParser instance that owns the |
| michael@0 | 46 | * nsHtml5AtomTable instance. |
| michael@0 | 47 | * |
| michael@0 | 48 | * Dynamic atoms (atoms whose IsStaticAtom() returns false) obtained from |
| michael@0 | 49 | * nsHtml5AtomTable must be re-obtained from another atom table when there's a |
| michael@0 | 50 | * need to migrate atoms from an nsHtml5Parser to its nsHtml5StreamParser |
| michael@0 | 51 | * (re-obtain from the other nsHtml5AtomTable), from an nsHtml5Parser to its |
| michael@0 | 52 | * owner nsHtml5Parser (re-obtain from the other nsHtml5AtomTable) or from the |
| michael@0 | 53 | * parser to the DOM (re-obtain from the application-wide atom table). To |
| michael@0 | 54 | * re-obtain an atom from another atom table, obtain a string from the atom |
| michael@0 | 55 | * using ToString(nsAString&) and look up an atom in the other table using that |
| michael@0 | 56 | * string. |
| michael@0 | 57 | * |
| michael@0 | 58 | * An instance of nsHtml5AtomTable that belongs to an nsHtml5Parser is only |
| michael@0 | 59 | * accessed from the main thread. An instance of nsHtml5AtomTable that belongs |
| michael@0 | 60 | * to an nsHtml5StreamParser is accessed both from the main thread and from the |
| michael@0 | 61 | * thread that executes the runnables of the nsHtml5StreamParser instance. |
| michael@0 | 62 | * However, the threads never access the nsHtml5AtomTable instance concurrently |
| michael@0 | 63 | * in the nsHtml5StreamParser case. |
| michael@0 | 64 | * |
| michael@0 | 65 | * Methods on the atoms obtained from nsHtml5AtomTable may be called on any |
| michael@0 | 66 | * thread, although they only need to be called on the main thread or on the |
| michael@0 | 67 | * thread working for the nsHtml5StreamParser when nsHtml5AtomTable belongs to |
| michael@0 | 68 | * an nsHtml5StreamParser. |
| michael@0 | 69 | * |
| michael@0 | 70 | * Dynamic atoms obtained from nsHtml5AtomTable are deleted when the |
| michael@0 | 71 | * nsHtml5AtomTable itself is destructed, which happens when the owner |
| michael@0 | 72 | * nsHtml5Parser or nsHtml5StreamParser is destructed. |
| michael@0 | 73 | */ |
| michael@0 | 74 | class nsHtml5AtomTable |
| michael@0 | 75 | { |
| michael@0 | 76 | public: |
| michael@0 | 77 | nsHtml5AtomTable(); |
| michael@0 | 78 | ~nsHtml5AtomTable(); |
| michael@0 | 79 | |
| michael@0 | 80 | /** |
| michael@0 | 81 | * Obtains the atom for the given string in the scope of this atom table. |
| michael@0 | 82 | */ |
| michael@0 | 83 | nsIAtom* GetAtom(const nsAString& aKey); |
| michael@0 | 84 | |
| michael@0 | 85 | /** |
| michael@0 | 86 | * Empties the table. |
| michael@0 | 87 | */ |
| michael@0 | 88 | void Clear() |
| michael@0 | 89 | { |
| michael@0 | 90 | mTable.Clear(); |
| michael@0 | 91 | } |
| michael@0 | 92 | |
| michael@0 | 93 | #ifdef DEBUG |
| michael@0 | 94 | void SetPermittedLookupThread(nsIThread* aThread) |
| michael@0 | 95 | { |
| michael@0 | 96 | mPermittedLookupThread = aThread; |
| michael@0 | 97 | } |
| michael@0 | 98 | #endif |
| michael@0 | 99 | |
| michael@0 | 100 | private: |
| michael@0 | 101 | nsTHashtable<nsHtml5AtomEntry> mTable; |
| michael@0 | 102 | #ifdef DEBUG |
| michael@0 | 103 | nsCOMPtr<nsIThread> mPermittedLookupThread; |
| michael@0 | 104 | #endif |
| michael@0 | 105 | }; |
| michael@0 | 106 | |
| michael@0 | 107 | #endif // nsHtml5AtomTable_h |
