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-rw-r--r--src/corelib/global/qrandom.cpp115
1 files changed, 34 insertions, 81 deletions
diff --git a/src/corelib/global/qrandom.cpp b/src/corelib/global/qrandom.cpp
index a7d4aa303a..2ee8f0dd01 100644
--- a/src/corelib/global/qrandom.cpp
+++ b/src/corelib/global/qrandom.cpp
@@ -48,7 +48,7 @@
#include <errno.h>
-#if !QT_CONFIG(getentropy) && !defined(Q_OS_BSD4) && !defined(Q_OS_WIN)
+#if !QT_CONFIG(getentropy) && (!defined(Q_OS_BSD4) || defined(__GLIBC__)) && !defined(Q_OS_WIN)
# include "qdeadlinetimer.h"
# include "qhashfunctions.h"
@@ -91,7 +91,7 @@ DECLSPEC_IMPORT BOOLEAN WINAPI SystemFunction036(PVOID RandomBuffer, ULONG Rando
QT_BEGIN_NAMESPACE
#if defined(Q_PROCESSOR_X86) && QT_COMPILER_SUPPORTS_HERE(RDRND)
-static qsizetype qt_random_cpu(void *buffer, qsizetype count) Q_DECL_NOTHROW;
+static qsizetype qt_random_cpu(void *buffer, qsizetype count) noexcept;
# ifdef Q_PROCESSOR_X86_64
# define _rdrandXX_step _rdrand64_step
@@ -99,7 +99,7 @@ static qsizetype qt_random_cpu(void *buffer, qsizetype count) Q_DECL_NOTHROW;
# define _rdrandXX_step _rdrand32_step
# endif
-static QT_FUNCTION_TARGET(RDRND) qsizetype qt_random_cpu(void *buffer, qsizetype count) Q_DECL_NOTHROW
+static QT_FUNCTION_TARGET(RDRND) qsizetype qt_random_cpu(void *buffer, qsizetype count) noexcept
{
unsigned *ptr = reinterpret_cast<unsigned *>(buffer);
unsigned *end = ptr + count;
@@ -134,7 +134,7 @@ enum {
struct QRandomGenerator::SystemGenerator
{
#if QT_CONFIG(getentropy)
- static qsizetype fillBuffer(void *buffer, qsizetype count) Q_DECL_NOTHROW
+ static qsizetype fillBuffer(void *buffer, qsizetype count) noexcept
{
// getentropy can read at most 256 bytes, so break the reading
qsizetype read = 0;
@@ -204,13 +204,13 @@ struct QRandomGenerator::SystemGenerator
}
#elif defined(Q_OS_WIN) && !defined(Q_OS_WINRT)
- qsizetype fillBuffer(void *buffer, qsizetype count) Q_DECL_NOTHROW
+ qsizetype fillBuffer(void *buffer, qsizetype count) noexcept
{
auto RtlGenRandom = SystemFunction036;
return RtlGenRandom(buffer, ULONG(count)) ? count: 0;
}
#elif defined(Q_OS_WINRT)
- qsizetype fillBuffer(void *, qsizetype) Q_DECL_NOTHROW
+ qsizetype fillBuffer(void *, qsizetype) noexcept
{
// always use the fallback
return 0;
@@ -218,7 +218,8 @@ struct QRandomGenerator::SystemGenerator
#endif // Q_OS_WINRT
static SystemGenerator &self();
- void generate(quint32 *begin, quint32 *end) Q_DECL_NOEXCEPT_EXPR(FillBufferNoexcept);
+ typedef quint32 result_type;
+ void generate(quint32 *begin, quint32 *end) noexcept(FillBufferNoexcept);
// For std::mersenne_twister_engine implementations that use something
// other than quint32 (unsigned int) to fill their buffers.
@@ -241,7 +242,7 @@ struct QRandomGenerator::SystemGenerator
#if defined(Q_OS_WIN)
static void fallback_update_seed(unsigned) {}
-static void fallback_fill(quint32 *ptr, qsizetype left) Q_DECL_NOTHROW
+static void fallback_fill(quint32 *ptr, qsizetype left) noexcept
{
// on Windows, rand_s is a high-quality random number generator
// and it requires no seeding
@@ -253,14 +254,14 @@ static void fallback_fill(quint32 *ptr, qsizetype left) Q_DECL_NOTHROW
}
#elif QT_CONFIG(getentropy)
static void fallback_update_seed(unsigned) {}
-static void fallback_fill(quint32 *, qsizetype) Q_DECL_NOTHROW
+static void fallback_fill(quint32 *, qsizetype) noexcept
{
// no fallback necessary, getentropy cannot fail under normal circumstances
Q_UNREACHABLE();
}
-#elif defined(Q_OS_BSD4)
+#elif defined(Q_OS_BSD4) && !defined(__GLIBC__)
static void fallback_update_seed(unsigned) {}
-static void fallback_fill(quint32 *ptr, qsizetype left) Q_DECL_NOTHROW
+static void fallback_fill(quint32 *ptr, qsizetype left) noexcept
{
// BSDs have arc4random(4) and these work even in chroot(2)
arc4random_buf(ptr, left * sizeof(*ptr));
@@ -279,7 +280,7 @@ Q_NEVER_INLINE
#ifdef Q_CC_GNU
__attribute__((cold)) // this function is pretty big, so optimize for size
#endif
-static void fallback_fill(quint32 *ptr, qsizetype left) Q_DECL_NOTHROW
+static void fallback_fill(quint32 *ptr, qsizetype left) noexcept
{
quint32 scratch[12]; // see element count below
quint32 *end = scratch;
@@ -353,7 +354,7 @@ static void fallback_fill(quint32 *ptr, qsizetype left) Q_DECL_NOTHROW
#endif
Q_NEVER_INLINE void QRandomGenerator::SystemGenerator::generate(quint32 *begin, quint32 *end)
- Q_DECL_NOEXCEPT_EXPR(FillBufferNoexcept)
+ noexcept(FillBufferNoexcept)
{
quint32 *buffer = begin;
qsizetype count = end - begin;
@@ -510,9 +511,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
those. The most common way of generating new values is to call the generate(),
generate64() or fillRange() functions. One would use it as:
- \code
- quint32 value = QRandomGenerator::global()->generate();
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 0
Additionally, it provides a floating-point function generateDouble() that
returns a number in the range [0, 1) (that is, inclusive of zero and
@@ -525,11 +524,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
the numbers generated by the object will always be the same, as in the
following example:
- \code
- QRandomGenerator prng1(1234), prng2(1234);
- Q_ASSERT(prng1.generate() == prng2.generate());
- Q_ASSERT(prng1.generate64() == prng2.generate64());
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 1
The seed data takes the form of one or more 32-bit words. The ideal seed
size is approximately equal to the size of the QRandomGenerator class
@@ -552,12 +547,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
For ease of use, QRandomGenerator provides a global object that can
be easily used, as in the following example:
- \code
- int x = QRandomGenerator::global()->generate();
- int y = QRandomGenerator::global()->generate();
- int w = QRandomGenerator::global()->bounded(16384);
- int h = QRandomGenerator::global()->bounded(16384);
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 2
\section1 System-wide random number generator
@@ -645,10 +635,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
following code may be used to generate a floating-point number in the range
[1, 2.5):
- \code
- std::uniform_real_distribution dist(1, 2.5);
- return dist(*QRandomGenerator::global());
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 3
\sa QRandomGenerator64, qrand()
*/
@@ -688,10 +675,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
with the same seed value will produce the same number sequence.
This constructor is equivalent to:
- \code
- std::seed_seq sseq(seedBuffer, seedBuffer + len);
- QRandomGenerator generator(sseq);
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 4
\sa seed(), securelySeeded()
*/
@@ -705,10 +689,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
with the same seed value will produce the same number sequence.
This constructor is equivalent to:
- \code
- std::seed_seq sseq(begin, end);
- QRandomGenerator generator(sseq);
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 5
\sa seed(), securelySeeded()
*/
@@ -828,10 +809,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
Discards the next \a z entries from the sequence. This method is equivalent
to calling generate() \a z times and discarding the result, as in:
- \code
- while (z--)
- generator.generate();
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 6
*/
/*!
@@ -840,9 +818,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
Generates 32-bit quantities and stores them in the range between \a begin
and \a end. This function is equivalent to (and is implemented as):
- \code
- std::generate(begin, end, [this]() { return generate(); });
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 7
This function complies with the requirements for the function
\l{http://en.cppreference.com/w/cpp/numeric/random/seed_seq/generate}{\c std::seed_seq::generate},
@@ -853,9 +829,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
32 bits of data. Any other bits will be zero. To fill the range with 64 bit
quantities, one can write:
- \code
- std::generate(begin, end, []() { return QRandomGenerator::global()->generate64(); });
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 8
If the range refers to contiguous memory (such as an array or the data from
a QVector), the fillRange() function may be used too.
@@ -882,11 +856,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
For example, to fill a vector of 16 entries with random values, one may
write:
- \code
- QVector<quint32> vector;
- vector.resize(16);
- QRandomGenerator::fillRange(vector.data(), vector.size());
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 9
\sa generate()
*/
@@ -901,10 +871,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
For example, to fill generate two 32-bit quantities, one may write:
- \code
- quint32 array[2];
- QRandomGenerator::fillRange(array);
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 10
It would have also been possible to make one call to generate64() and then split
the two halves of the 64-bit value.
@@ -919,10 +886,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
inclusive of zero and exclusive of 1).
This function is equivalent to:
- \code
- QRandomGenerator64 rd;
- return std::generate_canonical<qreal, std::numeric_limits<qreal>::digits>(rd);
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 11
The same may also be obtained by using
\l{http://en.cppreference.com/w/cpp/numeric/random/uniform_real_distribution}{\c std::uniform_real_distribution}
@@ -937,9 +901,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
Generates one random double in the range between 0 (inclusive) and \a
highest (exclusive). This function is equivalent to and is implemented as:
- \code
- return generateDouble() * highest;
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 12
\sa generateDouble(), bounded()
*/
@@ -956,9 +918,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
For example, to obtain a value between 0 and 255 (inclusive), one would write:
- \code
- quint32 v = QRandomGenerator::bounded(256);
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 13
Naturally, the same could also be obtained by masking the result of generate()
to only the lower 8 bits. Either solution is as efficient.
@@ -970,7 +930,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
*/
/*!
- \fn quint32 QRandomGenerator::bounded(int highest)
+ \fn int QRandomGenerator::bounded(int highest)
\overload
Generates one random 32-bit quantity in the range between 0 (inclusive) and
@@ -995,10 +955,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
For example, to obtain a value between 1000 (incl.) and 2000 (excl.), one
would write:
- \code
- quint32 v = QRandomGenerator::bounded(1000, 2000);
- \endcode
-
+ \snippet code/src_corelib_global_qrandom.cpp 14
Note that this function cannot be used to obtain values in the full 32-bit
range of quint32. Instead, use generate().
@@ -1007,7 +964,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
*/
/*!
- \fn quint32 QRandomGenerator::bounded(int lowest, int highest)
+ \fn int QRandomGenerator::bounded(int lowest, int highest)
\overload
Generates one random 32-bit quantity in the range between \a lowest
@@ -1053,9 +1010,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
For example, the following creates a random RGB color:
- \code
- return QColor::fromRgb(QRandomGenerator::global()->generate());
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 15
Accesses to this object are thread-safe and it may therefore be used in any
thread without locks. The object may also be copied and the sequence
@@ -1123,9 +1078,7 @@ inline QRandomGenerator::SystemGenerator &QRandomGenerator::SystemGenerator::sel
set. If you wish to cast the returned value to qint64 and keep it positive,
you should mask the sign bit off:
- \code
- qint64 value = QRandomGenerator64::generate() & std::numeric_limits<qint64>::max();
- \endcode
+ \snippet code/src_corelib_global_qrandom.cpp 16
\sa QRandomGenerator, QRandomGenerator::generate64()
*/
@@ -1214,7 +1167,7 @@ QRandomGenerator &QRandomGenerator::operator=(const QRandomGenerator &other)
return *this;
}
-QRandomGenerator::QRandomGenerator(std::seed_seq &sseq) Q_DECL_NOTHROW
+QRandomGenerator::QRandomGenerator(std::seed_seq &sseq) noexcept
: type(MersenneTwister)
{
Q_ASSERT(this != system());
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-08 07:15:26 +0000