From f6c1cebe42193a62fa0b9c6a881bb1a973b1b8a9 Mon Sep 17 00:00:00 2001 From: Thiago Macieira Date: Wed, 18 Dec 2019 18:17:38 -0800 Subject: QPluginLoader: rework the loading and the caching of instance There was a race condition in accessing the cached instance factory member, so rework loadPlugin() to return the cached or newly discovered instance, with proper, atomic caching. Because I had to change that, I took the opportunity to fix the QFactoryLoader code that calls loadPlugin(). Note that QLibraryPrivate::loadPlugin() returns non-nullptr now if the instance is known, which means the last return in QPluginLoader::load() will convert to true, not false, if the instance got cached between the earlier check and the call to loadPlugin(). That's probably what was intended. Task-number: QTBUG-39642 Change-Id: I46bf1f65e8db46afbde5fffd15e1a42d2b6cbf2c Reviewed-by: David Faure --- src/corelib/plugin/qfactoryloader.cpp | 15 ++++-------- src/corelib/plugin/qlibrary.cpp | 45 ++++++++++++++++++++++++++++------- src/corelib/plugin/qlibrary_p.h | 6 ++--- 3 files changed, 44 insertions(+), 22 deletions(-) (limited to 'src/corelib') diff --git a/src/corelib/plugin/qfactoryloader.cpp b/src/corelib/plugin/qfactoryloader.cpp index 18f10c9b43..9a6a69676d 100644 --- a/src/corelib/plugin/qfactoryloader.cpp +++ b/src/corelib/plugin/qfactoryloader.cpp @@ -389,17 +389,12 @@ QObject *QFactoryLoader::instance(int index) const QMutexLocker lock(&d->mutex); if (index < d->libraryList.size()) { QLibraryPrivate *library = d->libraryList.at(index); - if (library->instance || library->loadPlugin()) { - if (!library->inst) - library->inst = library->instance(); - QObject *obj = library->inst.data(); - if (obj) { - if (!obj->parent()) - obj->moveToThread(QCoreApplicationPrivate::mainThread()); - return obj; - } + if (QObject *obj = library->pluginInstance()) { + if (!obj->parent()) + obj->moveToThread(QCoreApplicationPrivate::mainThread()); + return obj; } - return 0; + return nullptr; } index -= d->libraryList.size(); lock.unlock(); diff --git a/src/corelib/plugin/qlibrary.cpp b/src/corelib/plugin/qlibrary.cpp index eeaa3c18ec..7ce959cc8f 100644 --- a/src/corelib/plugin/qlibrary.cpp +++ b/src/corelib/plugin/qlibrary.cpp @@ -498,7 +498,7 @@ inline void QLibraryStore::releaseLibrary(QLibraryPrivate *lib) } QLibraryPrivate::QLibraryPrivate(const QString &canonicalFileName, const QString &version, QLibrary::LoadHints loadHints) - : pHnd(0), fileName(canonicalFileName), fullVersion(version), instance(0), + : pHnd(0), fileName(canonicalFileName), fullVersion(version), libraryRefCount(0), libraryUnloadCount(0), pluginState(MightBeAPlugin) { loadHintsInt.storeRelaxed(loadHints); @@ -539,6 +539,32 @@ void QLibraryPrivate::setLoadHints(QLibrary::LoadHints lh) mergeLoadHints(lh); } +QObject *QLibraryPrivate::pluginInstance() +{ + // first, check if the instance is cached and hasn't been deleted + QObject *obj = inst.data(); + if (obj) + return obj; + + // We need to call the plugin's factory function. Is that cached? + // skip increasing the reference count (why? -Thiago) + QtPluginInstanceFunction factory = instanceFactory.loadAcquire(); + if (!factory) + factory = loadPlugin(); + + if (!factory) + return nullptr; + + obj = factory(); + + // cache again + if (inst) + obj = inst; + else + inst = obj; + return obj; +} + bool QLibraryPrivate::load() { if (pHnd) { @@ -585,7 +611,7 @@ bool QLibraryPrivate::unload(UnloadFlag flag) //can get deleted libraryRefCount.deref(); pHnd = 0; - instance = 0; + instanceFactory.storeRelaxed(nullptr); } } @@ -597,22 +623,23 @@ void QLibraryPrivate::release() QLibraryStore::releaseLibrary(this); } -bool QLibraryPrivate::loadPlugin() +QtPluginInstanceFunction QLibraryPrivate::loadPlugin() { - if (instance) { + if (auto ptr = instanceFactory.loadAcquire()) { libraryUnloadCount.ref(); - return true; + return ptr; } if (pluginState == IsNotAPlugin) - return false; + return nullptr; if (load()) { - instance = (QtPluginInstanceFunction)resolve("qt_plugin_instance"); - return instance; + auto ptr = reinterpret_cast(resolve("qt_plugin_instance")); + instanceFactory.storeRelease(ptr); // two threads may store the same value + return ptr; } if (qt_debug_component()) qWarning() << "QLibraryPrivate::loadPlugin failed on" << fileName << ":" << errorString; pluginState = IsNotAPlugin; - return false; + return nullptr; } /*! diff --git a/src/corelib/plugin/qlibrary_p.h b/src/corelib/plugin/qlibrary_p.h index db5afac98e..29724655a3 100644 --- a/src/corelib/plugin/qlibrary_p.h +++ b/src/corelib/plugin/qlibrary_p.h @@ -86,7 +86,7 @@ public: QString fullVersion; bool load(); - bool loadPlugin(); // loads and resolves instance + QtPluginInstanceFunction loadPlugin(); // loads and resolves instance bool unload(UnloadFlag flag = UnloadSys); void release(); QFunctionPointer resolve(const char *); @@ -100,8 +100,8 @@ public: static QStringList suffixes_sys(const QString &fullVersion); static QStringList prefixes_sys(); - QPointer inst; - QtPluginInstanceFunction instance; + QPointer inst; // used by QFactoryLoader + QAtomicPointer::type> instanceFactory; QJsonObject metaData; QString errorString; -- cgit v1.2.3 From ef92ac5636c2f0407fba8141c35ea61d391fd479 Mon Sep 17 00:00:00 2001 From: Thiago Macieira Date: Wed, 18 Dec 2019 18:31:55 -0800 Subject: QLibrary: stop setting errorString after resolve() resolve() is technically thread-safe if the library has been loadaed. We don't promise that, but it's there. More importantly, because QLibraryPrivate is shared among QPluginLoader and QLibrary that point to the same file, we can't thread-safely set the error string. [ChangeLog][Important Behavior Changes] QLibrary::resolve() will no longer set or clear the error string based on the success of finding the symbol. The error string will reflect the result of loading the library. Change-Id: I46bf1f65e8db46afbde5fffd15e1a4f4c2713c17 Reviewed-by: David Faure --- src/corelib/plugin/qlibrary_unix.cpp | 6 ------ src/corelib/plugin/qlibrary_win.cpp | 6 ------ 2 files changed, 12 deletions(-) (limited to 'src/corelib') diff --git a/src/corelib/plugin/qlibrary_unix.cpp b/src/corelib/plugin/qlibrary_unix.cpp index 135b82cd37..23f96dbdaf 100644 --- a/src/corelib/plugin/qlibrary_unix.cpp +++ b/src/corelib/plugin/qlibrary_unix.cpp @@ -317,12 +317,6 @@ Q_CORE_EXPORT QFunctionPointer qt_mac_resolve_sys(void *handle, const char *symb QFunctionPointer QLibraryPrivate::resolve_sys(const char* symbol) { QFunctionPointer address = QFunctionPointer(dlsym(pHnd, symbol)); - if (!address) { - errorString = QLibrary::tr("Cannot resolve symbol \"%1\" in %2: %3").arg( - QString::fromLatin1(symbol), fileName, qdlerror()); - } else { - errorString.clear(); - } return address; } diff --git a/src/corelib/plugin/qlibrary_win.cpp b/src/corelib/plugin/qlibrary_win.cpp index 05a93d467e..c8309104aa 100644 --- a/src/corelib/plugin/qlibrary_win.cpp +++ b/src/corelib/plugin/qlibrary_win.cpp @@ -162,12 +162,6 @@ bool QLibraryPrivate::unload_sys() QFunctionPointer QLibraryPrivate::resolve_sys(const char* symbol) { FARPROC address = GetProcAddress(pHnd, symbol); - if (!address) { - errorString = QLibrary::tr("Cannot resolve symbol \"%1\" in %2: %3").arg( - QString::fromLatin1(symbol), QDir::toNativeSeparators(fileName), qt_error_string()); - } else { - errorString.clear(); - } return QFunctionPointer(address); } QT_END_NAMESPACE -- cgit v1.2.3 From ae6f73e8566fa76470937aca737141183929a5ec Mon Sep 17 00:00:00 2001 From: Thiago Macieira Date: Wed, 18 Dec 2019 18:45:36 -0800 Subject: QLibrary: introduce a mutex to protect non-atomic internals And make pHnd atomic. The majority of the variables is updated in QLibraryPrivate::load_sys and updatePluginState(), which get the mutex protection. QLibraryPrivate::unload_sys() doesn't need a mutex protection because we have the refcounting. [ChangeLog][QtCore][QLibrary & QPluginLoader] Fixed a number of race conditions caused by having two QLibrary objects pointing to the same library being operated in different threads. Fixes: QTBUG-39642 Change-Id: I46bf1f65e8db46afbde5fffd15e1a5b3f5e74ea4 Reviewed-by: Lars Knoll --- src/corelib/plugin/qlibrary.cpp | 42 +++++++++++++++++++++++------------- src/corelib/plugin/qlibrary_p.h | 22 ++++++++++--------- src/corelib/plugin/qlibrary_unix.cpp | 24 +++++++++++---------- src/corelib/plugin/qlibrary_win.cpp | 24 +++++++++++---------- src/corelib/plugin/qpluginloader.cpp | 8 +++---- 5 files changed, 68 insertions(+), 52 deletions(-) (limited to 'src/corelib') diff --git a/src/corelib/plugin/qlibrary.cpp b/src/corelib/plugin/qlibrary.cpp index 7ce959cc8f..ddb053c26f 100644 --- a/src/corelib/plugin/qlibrary.cpp +++ b/src/corelib/plugin/qlibrary.cpp @@ -407,7 +407,7 @@ inline void QLibraryStore::cleanup() QLibraryPrivate *lib = it.value(); if (lib->libraryRefCount.loadRelaxed() == 1) { if (lib->libraryUnloadCount.loadRelaxed() > 0) { - Q_ASSERT(lib->pHnd); + Q_ASSERT(lib->pHnd.loadRelaxed()); lib->libraryUnloadCount.storeRelaxed(1); #ifdef __GLIBC__ // glibc has a bug in unloading from global destructors @@ -498,8 +498,7 @@ inline void QLibraryStore::releaseLibrary(QLibraryPrivate *lib) } QLibraryPrivate::QLibraryPrivate(const QString &canonicalFileName, const QString &version, QLibrary::LoadHints loadHints) - : pHnd(0), fileName(canonicalFileName), fullVersion(version), - libraryRefCount(0), libraryUnloadCount(0), pluginState(MightBeAPlugin) + : fileName(canonicalFileName), fullVersion(version), pluginState(MightBeAPlugin) { loadHintsInt.storeRelaxed(loadHints); if (canonicalFileName.isEmpty()) @@ -519,7 +518,7 @@ QLibraryPrivate::~QLibraryPrivate() void QLibraryPrivate::mergeLoadHints(QLibrary::LoadHints lh) { // if the library is already loaded, we can't change the load hints - if (pHnd) + if (pHnd.loadRelaxed()) return; loadHintsInt.storeRelaxed(lh); @@ -527,7 +526,7 @@ void QLibraryPrivate::mergeLoadHints(QLibrary::LoadHints lh) QFunctionPointer QLibraryPrivate::resolve(const char *symbol) { - if (!pHnd) + if (!pHnd.loadRelaxed()) return 0; return resolve_sys(symbol); } @@ -542,7 +541,7 @@ void QLibraryPrivate::setLoadHints(QLibrary::LoadHints lh) QObject *QLibraryPrivate::pluginInstance() { // first, check if the instance is cached and hasn't been deleted - QObject *obj = inst.data(); + QObject *obj = (QMutexLocker(&mutex), inst.data()); if (obj) return obj; @@ -558,6 +557,7 @@ QObject *QLibraryPrivate::pluginInstance() obj = factory(); // cache again + QMutexLocker locker(&mutex); if (inst) obj = inst; else @@ -567,7 +567,7 @@ QObject *QLibraryPrivate::pluginInstance() bool QLibraryPrivate::load() { - if (pHnd) { + if (pHnd.loadRelaxed()) { libraryUnloadCount.ref(); return true; } @@ -576,7 +576,9 @@ bool QLibraryPrivate::load() Q_TRACE(QLibraryPrivate_load_entry, fileName); + mutex.lock(); bool ret = load_sys(); + mutex.unlock(); if (qt_debug_component()) { if (ret) { qDebug() << "loaded library" << fileName; @@ -599,9 +601,10 @@ bool QLibraryPrivate::load() bool QLibraryPrivate::unload(UnloadFlag flag) { - if (!pHnd) + if (!pHnd.loadRelaxed()) return false; if (libraryUnloadCount.loadRelaxed() > 0 && !libraryUnloadCount.deref()) { // only unload if ALL QLibrary instance wanted to + QMutexLocker locker(&mutex); delete inst.data(); if (flag == NoUnloadSys || unload_sys()) { if (qt_debug_component()) @@ -610,12 +613,13 @@ bool QLibraryPrivate::unload(UnloadFlag flag) //when the library is unloaded, we release the reference on it so that 'this' //can get deleted libraryRefCount.deref(); - pHnd = 0; + pHnd.storeRelaxed(nullptr); instanceFactory.storeRelaxed(nullptr); + return true; } } - return (pHnd == 0); + return false; } void QLibraryPrivate::release() @@ -746,6 +750,7 @@ bool QLibraryPrivate::isPlugin() void QLibraryPrivate::updatePluginState() { + QMutexLocker locker(&mutex); errorString.clear(); if (pluginState != MightBeAPlugin) return; @@ -766,7 +771,7 @@ void QLibraryPrivate::updatePluginState() } #endif - if (!pHnd) { + if (!pHnd.loadRelaxed()) { // scan for the plugin metadata without loading success = findPatternUnloaded(fileName, this); } else { @@ -830,7 +835,7 @@ bool QLibrary::load() if (!d) return false; if (did_load) - return d->pHnd; + return d->pHnd.loadRelaxed(); did_load = true; return d->load(); } @@ -866,7 +871,7 @@ bool QLibrary::unload() */ bool QLibrary::isLoaded() const { - return d && d->pHnd; + return d && d->pHnd.loadRelaxed(); } @@ -977,8 +982,10 @@ void QLibrary::setFileName(const QString &fileName) QString QLibrary::fileName() const { - if (d) + if (d) { + QMutexLocker locker(&d->mutex); return d->qualifiedFileName.isEmpty() ? d->fileName : d->qualifiedFileName; + } return QString(); } @@ -1119,7 +1126,12 @@ QFunctionPointer QLibrary::resolve(const QString &fileName, const QString &versi */ QString QLibrary::errorString() const { - return (!d || d->errorString.isEmpty()) ? tr("Unknown error") : d->errorString; + QString str; + if (d) { + QMutexLocker locker(&d->mutex); + str = d->errorString; + } + return str.isEmpty() ? tr("Unknown error") : str; } /*! diff --git a/src/corelib/plugin/qlibrary_p.h b/src/corelib/plugin/qlibrary_p.h index 29724655a3..d756126c64 100644 --- a/src/corelib/plugin/qlibrary_p.h +++ b/src/corelib/plugin/qlibrary_p.h @@ -54,10 +54,10 @@ #include #include "QtCore/qlibrary.h" +#include "QtCore/qmutex.h" #include "QtCore/qpointer.h" #include "QtCore/qstringlist.h" #include "QtCore/qplugin.h" -#include "QtCore/qsharedpointer.h" #ifdef Q_OS_WIN # include "QtCore/qt_windows.h" #endif @@ -72,18 +72,15 @@ class QLibraryStore; class QLibraryPrivate { public: - #ifdef Q_OS_WIN - HINSTANCE + using Handle = HINSTANCE; #else - void * + using Handle = void *; #endif - pHnd; - enum UnloadFlag { UnloadSys, NoUnloadSys }; - QString fileName, qualifiedFileName; - QString fullVersion; + const QString fileName; + const QString fullVersion; bool load(); QtPluginInstanceFunction loadPlugin(); // loads and resolves instance @@ -94,17 +91,22 @@ public: QLibrary::LoadHints loadHints() const { return QLibrary::LoadHints(loadHintsInt.loadRelaxed()); } void setLoadHints(QLibrary::LoadHints lh); + QObject *pluginInstance(); static QLibraryPrivate *findOrCreate(const QString &fileName, const QString &version = QString(), QLibrary::LoadHints loadHints = nullptr); static QStringList suffixes_sys(const QString &fullVersion); static QStringList prefixes_sys(); - QPointer inst; // used by QFactoryLoader QAtomicPointer::type> instanceFactory; - QJsonObject metaData; + QAtomicPointer::type> pHnd; + // the mutex protects the fields below + QMutex mutex; + QPointer inst; // used by QFactoryLoader + QJsonObject metaData; QString errorString; + QString qualifiedFileName; void updatePluginState(); bool isPlugin(); diff --git a/src/corelib/plugin/qlibrary_unix.cpp b/src/corelib/plugin/qlibrary_unix.cpp index 23f96dbdaf..29813e5863 100644 --- a/src/corelib/plugin/qlibrary_unix.cpp +++ b/src/corelib/plugin/qlibrary_unix.cpp @@ -214,8 +214,9 @@ bool QLibraryPrivate::load_sys() #endif bool retry = true; - for(int prefix = 0; retry && !pHnd && prefix < prefixes.size(); prefix++) { - for(int suffix = 0; retry && !pHnd && suffix < suffixes.size(); suffix++) { + Handle hnd = nullptr; + for (int prefix = 0; retry && !hnd && prefix < prefixes.size(); prefix++) { + for (int suffix = 0; retry && !hnd && suffix < suffixes.size(); suffix++) { if (!prefixes.at(prefix).isEmpty() && name.startsWith(prefixes.at(prefix))) continue; if (path.isEmpty() && prefixes.at(prefix).contains(QLatin1Char('/'))) @@ -232,7 +233,7 @@ bool QLibraryPrivate::load_sys() attempt = path + prefixes.at(prefix) + name + suffixes.at(suffix); } - pHnd = dlopen(QFile::encodeName(attempt), dlFlags); + hnd = dlopen(QFile::encodeName(attempt), dlFlags); #ifdef Q_OS_ANDROID if (!pHnd) { auto attemptFromBundle = attempt; @@ -248,7 +249,7 @@ bool QLibraryPrivate::load_sys() } #endif - if (!pHnd && fileName.startsWith(QLatin1Char('/')) && QFile::exists(attempt)) { + if (!hnd && fileName.startsWith(QLatin1Char('/')) && QFile::exists(attempt)) { // We only want to continue if dlopen failed due to that the shared library did not exist. // However, we are only able to apply this check for absolute filenames (since they are // not influenced by the content of LD_LIBRARY_PATH, /etc/ld.so.cache, DT_RPATH etc...) @@ -259,7 +260,7 @@ bool QLibraryPrivate::load_sys() } #ifdef Q_OS_MAC - if (!pHnd) { + if (!hnd) { QByteArray utf8Bundle = fileName.toUtf8(); QCFType bundleUrl = CFURLCreateFromFileSystemRepresentation(NULL, reinterpret_cast(utf8Bundle.data()), utf8Bundle.length(), true); QCFType bundle = CFBundleCreate(NULL, bundleUrl); @@ -268,23 +269,24 @@ bool QLibraryPrivate::load_sys() char executableFile[FILENAME_MAX]; CFURLGetFileSystemRepresentation(url, true, reinterpret_cast(executableFile), FILENAME_MAX); attempt = QString::fromUtf8(executableFile); - pHnd = dlopen(QFile::encodeName(attempt), dlFlags); + hnd = dlopen(QFile::encodeName(attempt), dlFlags); } } #endif - if (!pHnd) { + if (!hnd) { errorString = QLibrary::tr("Cannot load library %1: %2").arg(fileName, qdlerror()); } - if (pHnd) { + if (hnd) { qualifiedFileName = attempt; errorString.clear(); } - return (pHnd != 0); + pHnd.storeRelaxed(hnd); + return (hnd != nullptr); } bool QLibraryPrivate::unload_sys() { - if (dlclose(pHnd)) { + if (dlclose(pHnd.loadAcquire())) { #if defined (Q_OS_QNX) // Workaround until fixed in QNX; fixes crash in char *error = dlerror(); // QtDeclarative auto test "qqmlenginecleanup" for instance if (!qstrcmp(error, "Shared objects still referenced")) // On QNX that's only "informative" @@ -316,7 +318,7 @@ Q_CORE_EXPORT QFunctionPointer qt_mac_resolve_sys(void *handle, const char *symb QFunctionPointer QLibraryPrivate::resolve_sys(const char* symbol) { - QFunctionPointer address = QFunctionPointer(dlsym(pHnd, symbol)); + QFunctionPointer address = QFunctionPointer(dlsym(pHnd.loadAcquire(), symbol)); return address; } diff --git a/src/corelib/plugin/qlibrary_win.cpp b/src/corelib/plugin/qlibrary_win.cpp index c8309104aa..000bf76276 100644 --- a/src/corelib/plugin/qlibrary_win.cpp +++ b/src/corelib/plugin/qlibrary_win.cpp @@ -95,26 +95,27 @@ bool QLibraryPrivate::load_sys() attempts.prepend(QDir::rootPath() + fileName); #endif + Handle hnd = nullptr; for (const QString &attempt : qAsConst(attempts)) { #ifndef Q_OS_WINRT - pHnd = LoadLibrary(reinterpret_cast(QDir::toNativeSeparators(attempt).utf16())); + hnd = LoadLibrary(reinterpret_cast(QDir::toNativeSeparators(attempt).utf16())); #else // Q_OS_WINRT QString path = QDir::toNativeSeparators(QDir::current().relativeFilePath(attempt)); - pHnd = LoadPackagedLibrary(reinterpret_cast(path.utf16()), 0); - if (pHnd) + hnd = LoadPackagedLibrary(reinterpret_cast(path.utf16()), 0); + if (hnd) qualifiedFileName = attempt; #endif // !Q_OS_WINRT // If we have a handle or the last error is something other than "unable // to find the module", then bail out - if (pHnd || ::GetLastError() != ERROR_MOD_NOT_FOUND) + if (hnd || ::GetLastError() != ERROR_MOD_NOT_FOUND) break; } #ifndef Q_OS_WINRT SetErrorMode(oldmode); #endif - if (!pHnd) { + if (!hnd) { errorString = QLibrary::tr("Cannot load library %1: %2").arg( QDir::toNativeSeparators(fileName), qt_error_string()); } else { @@ -123,7 +124,7 @@ bool QLibraryPrivate::load_sys() #ifndef Q_OS_WINRT wchar_t buffer[MAX_PATH]; - ::GetModuleFileName(pHnd, buffer, MAX_PATH); + ::GetModuleFileName(hnd, buffer, MAX_PATH); QString moduleFileName = QString::fromWCharArray(buffer); moduleFileName.remove(0, 1 + moduleFileName.lastIndexOf(QLatin1Char('\\'))); @@ -138,19 +139,20 @@ bool QLibraryPrivate::load_sys() HMODULE hmod; bool ok = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_PIN | GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS, - reinterpret_cast(pHnd), + reinterpret_cast(hnd), &hmod); - Q_ASSERT(!ok || hmod == pHnd); + Q_ASSERT(!ok || hmod == hnd); Q_UNUSED(ok); } #endif // !Q_OS_WINRT } - return (pHnd != 0); + pHnd.storeRelaxed(hnd); + return (pHnd != nullptr); } bool QLibraryPrivate::unload_sys() { - if (!FreeLibrary(pHnd)) { + if (!FreeLibrary(pHnd.loadAcquire())) { errorString = QLibrary::tr("Cannot unload library %1: %2").arg( QDir::toNativeSeparators(fileName), qt_error_string()); return false; @@ -161,7 +163,7 @@ bool QLibraryPrivate::unload_sys() QFunctionPointer QLibraryPrivate::resolve_sys(const char* symbol) { - FARPROC address = GetProcAddress(pHnd, symbol); + FARPROC address = GetProcAddress(pHnd.loadAcquire(), symbol); return QFunctionPointer(address); } QT_END_NAMESPACE diff --git a/src/corelib/plugin/qpluginloader.cpp b/src/corelib/plugin/qpluginloader.cpp index dac8502dae..0e12793d5e 100644 --- a/src/corelib/plugin/qpluginloader.cpp +++ b/src/corelib/plugin/qpluginloader.cpp @@ -196,9 +196,7 @@ QObject *QPluginLoader::instance() { if (!isLoaded() && !load()) return 0; - if (!d->inst && d->instance) - d->inst = d->instance(); - return d->inst.data(); + return d->pluginInstance(); } /*! @@ -233,7 +231,7 @@ bool QPluginLoader::load() if (!d || d->fileName.isEmpty()) return false; if (did_load) - return d->pHnd && d->instance; + return d->pHnd && d->instanceFactory.loadAcquire(); if (!d->isPlugin()) return false; did_load = true; @@ -275,7 +273,7 @@ bool QPluginLoader::unload() */ bool QPluginLoader::isLoaded() const { - return d && d->pHnd && d->instance; + return d && d->pHnd && d->instanceFactory.loadRelaxed(); } #if defined(QT_SHARED) -- cgit v1.2.3 From c1bb6285720513b9b22b552ca30af3c1501a7761 Mon Sep 17 00:00:00 2001 From: Marc Mutz Date: Thu, 5 Mar 2020 15:57:07 +0100 Subject: Port from deprecated std::is_pod to is_trivial + is_standard_layout The std::is_pod trait is deprecated in C++20; is_trivial and is_standard_layout exist since C++11. Change-Id: I4b901d8edf1a55001764445aee9c338d3dc23b21 Reviewed-by: Lars Knoll --- src/corelib/kernel/qmetatype.cpp | 3 ++- src/corelib/serialization/qcborvalue_p.h | 3 ++- 2 files changed, 4 insertions(+), 2 deletions(-) (limited to 'src/corelib') diff --git a/src/corelib/kernel/qmetatype.cpp b/src/corelib/kernel/qmetatype.cpp index 356a675517..9fc0659cf2 100644 --- a/src/corelib/kernel/qmetatype.cpp +++ b/src/corelib/kernel/qmetatype.cpp @@ -589,7 +589,8 @@ QMetaTypeComparatorRegistry; typedef QMetaTypeFunctionRegistry QMetaTypeDebugStreamRegistry; -Q_STATIC_ASSERT(std::is_pod::value); +Q_STATIC_ASSERT(std::is_trivial::value); +Q_STATIC_ASSERT(std::is_standard_layout::value); Q_DECLARE_TYPEINFO(QCustomTypeInfo, Q_MOVABLE_TYPE); Q_GLOBAL_STATIC(QVector, customTypes) diff --git a/src/corelib/serialization/qcborvalue_p.h b/src/corelib/serialization/qcborvalue_p.h index 48818e4c63..a74ac2ba10 100644 --- a/src/corelib/serialization/qcborvalue_p.h +++ b/src/corelib/serialization/qcborvalue_p.h @@ -115,7 +115,8 @@ struct ByteData QStringView asStringView() const{ return QStringView(utf16(), len / 2); } QString asQStringRaw() const { return QString::fromRawData(utf16(), len / 2); } }; -Q_STATIC_ASSERT(std::is_pod::value); +Q_STATIC_ASSERT(std::is_trivial::value); +Q_STATIC_ASSERT(std::is_standard_layout::value); } // namespace QtCbor Q_DECLARE_TYPEINFO(QtCbor::Element, Q_PRIMITIVE_TYPE); -- cgit v1.2.3 From 3702a4c37e06a989cdd1cf19a26bc0d1c3fba07c Mon Sep 17 00:00:00 2001 From: Christian Ehrlicher Date: Sun, 8 Mar 2020 19:52:18 +0100 Subject: QSortFilterProxyModel doc: do not mention deprecated function reset() QSFPM::reset() is deprecated and begin/endResetModel() should be used. Therefore adjust the documentation to reflect this. Fixes: QTBUG-82470 Change-Id: I786b3f25e5674d97d0ef6a0c91342973d5e952e9 Reviewed-by: Sze Howe Koh Reviewed-by: Paul Wicking --- src/corelib/itemmodels/qsortfilterproxymodel.cpp | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'src/corelib') diff --git a/src/corelib/itemmodels/qsortfilterproxymodel.cpp b/src/corelib/itemmodels/qsortfilterproxymodel.cpp index 61d37d5062..122b95ed57 100644 --- a/src/corelib/itemmodels/qsortfilterproxymodel.cpp +++ b/src/corelib/itemmodels/qsortfilterproxymodel.cpp @@ -1949,8 +1949,9 @@ void QSortFilterProxyModelPrivate::_q_sourceColumnsMoved( example.) If you are working with large amounts of filtering and have to invoke - invalidateFilter() repeatedly, using reset() may be more efficient, - depending on the implementation of your model. However, reset() returns the + invalidateFilter() repeatedly, using beginResetModel() / endResetModel() may + be more efficient, depending on the implementation of your model. However, + beginResetModel() / endResetModel() returns the proxy model to its original state, losing selection information, and will cause the proxy model to be repopulated. -- cgit v1.2.3