1 files changed, 37 insertions, 24 deletions

diff --git a/src/corelib/tools/qbytearray.cpp b/src/corelib/tools/qbytearray.cpp
index fb92d82f07..52af67c86a 100644
--- a/src/corelib/tools/qbytearray.cpp
+++ b/src/corelib/tools/qbytearray.cpp
@@ -48,6 +48,7 @@
 #include "qlocale_p.h"
 #include "qscopedpointer.h"
 #include <qdatastream.h>
+#include <qmath.h>
 
 #ifndef QT_NO_COMPRESS
 #include <zlib.h>
@@ -67,24 +68,12 @@ int qFindByteArray(
     const char *needle0, int needleLen);
 
 
-int qAllocMore(int alloc, int extra)
+int qAllocMore(int alloc, int extra) Q_DECL_NOTHROW
 {
     Q_ASSERT(alloc >= 0 && extra >= 0);
     Q_ASSERT_X(alloc < (1 << 30) - extra, "qAllocMore", "Requested size is too large!");
 
-    unsigned nalloc = alloc + extra;
-
-    // Round up to next power of 2
-
-    // Assuming container is growing, always overshoot
-    //--nalloc;
-
-    nalloc |= nalloc >> 1;
-    nalloc |= nalloc >> 2;
-    nalloc |= nalloc >> 4;
-    nalloc |= nalloc >> 8;
-    nalloc |= nalloc >> 16;
-    ++nalloc;
+    unsigned nalloc = qNextPowerOfTwo(alloc + extra);
 
     Q_ASSERT(nalloc > unsigned(alloc + extra));
 
@@ -2677,19 +2666,22 @@ QByteArray QByteArray::right(int len) const
 
 QByteArray QByteArray::mid(int pos, int len) const
 {
-    if ((d->size == 0 && d->ref.isStatic()) || pos > d->size)
+    using namespace QtPrivate;
+    switch (QContainerImplHelper::mid(size(), &pos, &len)) {
+    case QContainerImplHelper::Null:
         return QByteArray();
-    if (len < 0)
-        len = d->size - pos;
-    if (pos < 0) {
-        len += pos;
-        pos = 0;
+    case QContainerImplHelper::Empty:
+    {
+        QByteArrayDataPtr empty = { Data::allocate(0) };
+        return QByteArray(empty);
     }
-    if (len + pos > d->size)
-        len = d->size - pos;
-    if (pos == 0 && len == d->size)
+    case QContainerImplHelper::Full:
         return *this;
-    return QByteArray(d->data() + pos, len);
+    case QContainerImplHelper::Subset:
+        return QByteArray(d->data() + pos, len);
+    }
+    Q_UNREACHABLE();
+    return QByteArray();
 }
 
 /*!
@@ -4186,6 +4178,27 @@ QByteArray QByteArray::fromPercentEncoding(const QByteArray &input, char percent
     return tmp;
 }
 
+/*! \fn QByteArray QByteArray::fromStdString(const std::string &str)
+    \since 5.4
+
+    Returns a copy of the \a str string as a QByteArray.
+
+    \sa toStdString(), QString::fromStdString()
+*/
+
+/*!
+    \fn std::string QByteArray::toStdString() const
+    \since 5.4
+
+    Returns a std::string object with the data contained in this
+    QByteArray.
+
+    This operator is mostly useful to pass a QByteArray to a function
+    that accepts a std::string object.
+
+    \sa fromStdString(), QString::toStdString()
+*/
+
 /*! \fn QByteArray QByteArray::fromCFData(CFDataRef data)
     \since 5.3