diff options
| author | Robin Burchell <robin.burchell@jollamobile.com> | 2013-11-13 14:54:49 +0100 |
|---|---|---|
| committer | The Qt Project <gerrit-noreply@qt-project.org> | 2013-11-20 19:25:56 +0100 |
| commit | 52ba7b1ffcb90772dc97b3e9a34beee5781ed2d7 (patch) | |
| tree | 7c710ebbd3896f508a4d9fb2777c6696f363b1e0 /src/gui/text/qfont.cpp | |
| parent | e70ecc06b1e266b73f47291aa037114bd3d1baf7 (diff) | |
Cleanup freetype data in a thread-safe way
One less obvious part of this patch: the fontCache pointer in engineData was not
safe. It isn't safe to rely on pointer addresses to verify we're cleaning up the
right thing, as a sequence of malloc()/free()/malloc() can return the same
pointer, and nothing was cleaning up the dangling pointer in engineData.
With this, it is possible to safely drop OpenGL contexts in QtQuick under all
conditions with no possibility of crashes.
Done-with: Aaron Kennedy <aaron.kennedy@jollamobile.com>
Change-Id: I7b91384251593730124323a74737d41333a05f59
Reviewed-by: Konstantin Ritt <ritt.ks@gmail.com>
Reviewed-by: Eskil Abrahamsen Blomfeldt <eskil.abrahamsen-blomfeldt@digia.com>
Diffstat (limited to 'src/gui/text/qfont.cpp')
| -rw-r--r-- | src/gui/text/qfont.cpp | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/src/gui/text/qfont.cpp b/src/gui/text/qfont.cpp index a410004c06..49b5a9ba46 100644 --- a/src/gui/text/qfont.cpp +++ b/src/gui/text/qfont.cpp @@ -208,7 +208,7 @@ QFontEngine *QFontPrivate::engineForScript(int script) const QMutexLocker locker(qt_fontdatabase_mutex()); if (script <= QChar::Script_Latin) script = QChar::Script_Common; - if (engineData && engineData->fontCache != QFontCache::instance()) { + if (engineData && engineData->fontCacheId != QFontCache::instance()->id()) { // throw out engineData that came from a different thread if (!engineData->ref.deref()) delete engineData; @@ -317,7 +317,7 @@ void QFontPrivate::resolve(uint mask, const QFontPrivate *other) QFontEngineData::QFontEngineData() - : ref(0), fontCache(QFontCache::instance()) + : ref(0), fontCacheId(QFontCache::instance()->id()) { memset(engines, 0, QChar::ScriptCount * sizeof(QFontEngine *)); } @@ -2638,9 +2638,12 @@ void QFontCache::cleanup() } #endif // QT_NO_THREAD +QBasicAtomicInt font_cache_id = Q_BASIC_ATOMIC_INITIALIZER(1); + QFontCache::QFontCache() : QObject(), total_cost(0), max_cost(min_cost), - current_timestamp(0), fast(false), timer_id(-1) + current_timestamp(0), fast(false), timer_id(-1), + m_id(font_cache_id.fetchAndAddRelaxed(1)) { } |