diff options
| -rw-r--r-- | src/corelib/global/qglobal.cpp | 49 | ||||
| -rw-r--r-- | src/corelib/plugin/quuid.cpp | 22 |
2 files changed, 16 insertions, 55 deletions
diff --git a/src/corelib/global/qglobal.cpp b/src/corelib/global/qglobal.cpp index 75a51ec..c956b85 100644 --- a/src/corelib/global/qglobal.cpp +++ b/src/corelib/global/qglobal.cpp @@ -2606,55 +2606,6 @@ void qsrand(uint seed) #endif } -/*! \internal - \relates <QtGlobal> - \since 4.6 - - Seed the PRNG, but only if it has not already been seeded. - - The default seed is a combination of current time, a stack address and a - serial counter (since thread stack addresses are re-used). -*/ -void qsrand() -{ -#if (defined(Q_OS_UNIX) || defined(Q_OS_WIN)) && !defined(QT_NO_THREAD) - SeedStorage *seedStorage = randTLS(); - if (seedStorage) { - SeedStorageType *pseed = seedStorage->localData(); - if (pseed) { - // already seeded - return; - } - seedStorage->setLocalData(pseed = new SeedStorageType); - // start beyond 1 to avoid the sequence reset - static QBasicAtomicInt serial = Q_BASIC_ATOMIC_INITIALIZER(2); - *pseed = QDateTime::currentDateTime().toTime_t() - + quintptr(&pseed) - + serial.fetchAndAddRelaxed(1); -#if defined(Q_OS_WIN) || defined(Q_OS_SYMBIAN) - // for Windows and Symbian the srand function must still be called. - srand(*pseed); -#endif - } - -//QT_NO_THREAD implementations -#else - static unsigned int seed = 0; - - if (seed) - return; - -#if defined(Q_OS_SYMBIAN) - seed = Math::Random(); -#elif defined(Q_OS_WIN) - seed = GetTickCount(); -#else - seed = quintptr(&seed) + QDateTime::currentDateTime().toTime_t(); -#endif - srand(seed); -#endif // defined(Q_OS_UNIX) || defined(Q_OS_WIN)) && !defined(QT_NO_THREAD) -} - /*! \relates <QtGlobal> \since 4.2 diff --git a/src/corelib/plugin/quuid.cpp b/src/corelib/plugin/quuid.cpp index 9332bbc..7858b33 100644 --- a/src/corelib/plugin/quuid.cpp +++ b/src/corelib/plugin/quuid.cpp @@ -578,11 +578,9 @@ QUuid QUuid::createUuid() QT_BEGIN_INCLUDE_NAMESPACE #include "qdatetime.h" #include "qfile.h" -#include "stdlib.h" // For srand/rand +#include "qthreadstorage.h" QT_END_INCLUDE_NAMESPACE -extern void qsrand(); // in qglobal.cpp - QUuid QUuid::createUuid() { QUuid result; @@ -600,12 +598,24 @@ QUuid QUuid::createUuid() static const int intbits = sizeof(int)*8; static int randbits = 0; if (!randbits) { + int r = 0; int max = RAND_MAX; - do { ++randbits; } while ((max=max>>1)); + do { ++r; } while ((max=max>>1)); + randbits = r; } - // reseed, but only if not already seeded - qsrand(); + static QThreadStorage<int *> uuidseed; + if (!uuidseed.hasLocalData()) { + // Seed the PRNG once per thread with a combination of current time, a + // stack address and a serial counter (since thread stack addresses are + // re-used). + int *pseed = new int; + static QBasicAtomicInt serial = Q_BASIC_ATOMIC_INITIALIZER(2); + qsrand(*pseed = QDateTime::currentDateTime().toTime_t() + + quintptr(&pseed) + + serial.fetchAndAddRelaxed(1)); + uuidseed.setLocalData(pseed); + } int chunks = 16 / sizeof(uint); while (chunks--) { |