Make reallocData() take (unsigned) size, including null

The parameter represents an allocation size and unsigned matches the
Q*Data::alloc member it ultimately represents (even if they currently
differ in accounting for the null).

There's still work up for grabs to ensure we avoid integer overflows
when growing.

Change-Id: Ib092fec37ec2ceed37bebfdc52e2de27b336328f
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

4 files changed, 38 insertions, 38 deletions

diff --git a/src/corelib/tools/qbytearray.cpp b/src/corelib/tools/qbytearray.cpp
index 32834ebd7e..43f666e075 100644
--- a/src/corelib/tools/qbytearray.cpp
+++ b/src/corelib/tools/qbytearray.cpp
@@ -919,7 +919,7 @@ QByteArray &QByteArray::operator=(const char *str)
     } else {
         int len = strlen(str);
         if (d->ref.isShared() || len > int(d->alloc) || (len < d->size && len < int(d->alloc) >> 1))
-            reallocData(len);
+            reallocData(uint(len) + 1u);
         x = d;
         memcpy(x->data(), str, len + 1); // include null terminator
         x->size = len;
@@ -1432,7 +1432,7 @@ void QByteArray::resize(int size)
     } else {
         if (d->ref.isShared() || size > int(d->alloc)
             || (!d->capacityReserved && size < d->size && size < int(d->alloc) >> 1))
-            reallocData(size, true);
+            reallocData(uint(size) + 1u, true);
         if (d->alloc) {
             d->size = size;
             d->data()[size] = '\0';
@@ -1459,17 +1459,17 @@ QByteArray &QByteArray::fill(char ch, int size)
     return *this;
 }
 
-void QByteArray::reallocData(int alloc, bool grow)
+void QByteArray::reallocData(uint alloc, bool grow)
 {
     if (grow)
-        alloc = qAllocMore(alloc + 1, sizeof(Data)) - 1;
+        alloc = qAllocMore(alloc, sizeof(Data));
 
     if (d->ref.isShared() || IS_RAW_DATA(d)) {
-        Data *x = static_cast<Data *>(malloc(sizeof(Data) + alloc + 1));
+        Data *x = static_cast<Data *>(malloc(sizeof(Data) + alloc));
         Q_CHECK_PTR(x);
         x->ref.initializeOwned();
-        x->size = qMin(alloc, d->size);
-        x->alloc = alloc;
+        x->size = qMin(int(alloc) - 1, d->size);
+        x->alloc = alloc - 1u;
         x->capacityReserved = d->capacityReserved;
         x->offset = sizeof(QByteArrayData);
         ::memcpy(x->data(), d->data(), x->size);
@@ -1478,9 +1478,9 @@ void QByteArray::reallocData(int alloc, bool grow)
             free(d);
         d = x;
     } else {
-        Data *x = static_cast<Data *>(::realloc(d, sizeof(Data) + alloc + 1));
+        Data *x = static_cast<Data *>(::realloc(d, sizeof(Data) + alloc));
         Q_CHECK_PTR(x);
-        x->alloc = alloc;
+        x->alloc = alloc - 1u;
         x->offset = sizeof(QByteArrayData);
         d = x;
     }
@@ -1566,7 +1566,7 @@ QByteArray &QByteArray::prepend(const char *str, int len)
 {
     if (str) {
         if (d->ref.isShared() || d->size + len > int(d->alloc))
-            reallocData(d->size + len, true);
+            reallocData(uint(d->size + len) + 1u, true);
         memmove(d->data()+len, d->data(), d->size);
         memcpy(d->data(), str, len);
         d->size += len;
@@ -1584,7 +1584,7 @@ QByteArray &QByteArray::prepend(const char *str, int len)
 QByteArray &QByteArray::prepend(char ch)
 {
     if (d->ref.isShared() || d->size + 1 > int(d->alloc))
-        reallocData(d->size + 1, true);
+        reallocData(uint(d->size) + 2u, true);
     memmove(d->data()+1, d->data(), d->size);
     d->data()[0] = ch;
     ++d->size;
@@ -1622,7 +1622,7 @@ QByteArray &QByteArray::append(const QByteArray &ba)
         *this = ba;
     } else if (ba.d != &shared_null.ba) {
         if (d->ref.isShared() || d->size + ba.d->size > int(d->alloc))
-            reallocData(d->size + ba.d->size, true);
+            reallocData(uint(d->size + ba.d->size) + 1u, true);
         memcpy(d->data() + d->size, ba.d->data(), ba.d->size);
         d->size += ba.d->size;
         d->data()[d->size] = '\0';
@@ -1656,7 +1656,7 @@ QByteArray& QByteArray::append(const char *str)
     if (str) {
         int len = strlen(str);
         if (d->ref.isShared() || d->size + len > int(d->alloc))
-            reallocData(d->size + len, true);
+            reallocData(uint(d->size + len) + 1u, true);
         memcpy(d->data() + d->size, str, len + 1); // include null terminator
         d->size += len;
     }
@@ -1681,7 +1681,7 @@ QByteArray &QByteArray::append(const char *str, int len)
         len = qstrlen(str);
     if (str && len) {
         if (d->ref.isShared() || d->size + len > int(d->alloc))
-            reallocData(d->size + len, true);
+            reallocData(uint(d->size + len) + 1u, true);
         memcpy(d->data() + d->size, str, len); // include null terminator
         d->size += len;
         d->data()[d->size] = '\0';
@@ -1698,7 +1698,7 @@ QByteArray &QByteArray::append(const char *str, int len)
 QByteArray& QByteArray::append(char ch)
 {
     if (d->ref.isShared() || d->size + 1 > int(d->alloc))
-        reallocData(d->size + 1, true);
+        reallocData(uint(d->size) + 2u, true);
     d->data()[d->size++] = ch;
     d->data()[d->size] = '\0';
     return *this;
diff --git a/src/corelib/tools/qbytearray.h b/src/corelib/tools/qbytearray.h
index 37c5f72040..287245182a 100644
--- a/src/corelib/tools/qbytearray.h
+++ b/src/corelib/tools/qbytearray.h
@@ -406,7 +406,7 @@ private:
     static const QStaticByteArrayData<1> shared_null;
     static const QStaticByteArrayData<1> shared_empty;
     Data *d;
-    void reallocData(int alloc, bool grow = false);
+    void reallocData(uint alloc, bool grow = false);
     void expand(int i);
     QByteArray nulTerminated() const;
 
@@ -445,7 +445,7 @@ inline const char *QByteArray::data() const
 inline const char *QByteArray::constData() const
 { return d->data(); }
 inline void QByteArray::detach()
-{ if (d->ref.isShared() || (d->offset != sizeof(QByteArrayData))) reallocData(d->size); }
+{ if (d->ref.isShared() || (d->offset != sizeof(QByteArrayData))) reallocData(uint(d->size) + 1u); }
 inline bool QByteArray::isDetached() const
 { return !d->ref.isShared(); }
 inline QByteArray::QByteArray(const QByteArray &a) : d(a.d)
@@ -457,7 +457,7 @@ inline int QByteArray::capacity() const
 inline void QByteArray::reserve(int asize)
 {
     if (d->ref.isShared() || asize > int(d->alloc))
-        reallocData(asize);
+        reallocData(uint(asize) + 1u);
 
     if (!d->capacityReserved) {
         // cannot set unconditionally, since d could be the shared_null/shared_empty (which is const)
@@ -468,7 +468,7 @@ inline void QByteArray::reserve(int asize)
 inline void QByteArray::squeeze()
 {
     if (d->ref.isShared() || d->size < int(d->alloc))
-        reallocData(d->size);
+        reallocData(uint(d->size) + 1u);
 
     if (d->capacityReserved) {
         // cannot set unconditionally, since d could be shared_null or
diff --git a/src/corelib/tools/qstring.cpp b/src/corelib/tools/qstring.cpp
index 2bb439d703..bc39eafb6d 100644
--- a/src/corelib/tools/qstring.cpp
+++ b/src/corelib/tools/qstring.cpp
@@ -1236,7 +1236,7 @@ void QString::resize(int size)
     } else {
         if (d->ref.isShared() || size > int(d->alloc) ||
             (!d->capacityReserved && size < d->size && size < int(d->alloc) >> 1))
-            reallocData(size, true);
+            reallocData(uint(size) + 1u, true);
         if (d->alloc) {
             d->size = size;
             d->data()[size] = '\0';
@@ -1294,17 +1294,17 @@ void QString::resize(int size)
     \sa reserve(), capacity()
 */
 
-void QString::reallocData(int alloc, bool grow)
+void QString::reallocData(uint alloc, bool grow)
 {
     if (grow)
-        alloc = qAllocMore((alloc+1) * sizeof(QChar), sizeof(Data)) / sizeof(QChar) - 1;
+        alloc = qAllocMore(alloc * sizeof(QChar), sizeof(Data)) / sizeof(QChar);
 
     if (d->ref.isShared() || IS_RAW_DATA(d)) {
-        Data *x = static_cast<Data *>(::malloc(sizeof(Data) + (alloc+1) * sizeof(QChar)));
+        Data *x = static_cast<Data *>(::malloc(sizeof(Data) + alloc * sizeof(QChar)));
         Q_CHECK_PTR(x);
         x->ref.initializeOwned();
-        x->size = qMin(alloc, d->size);
-        x->alloc = (uint) alloc;
+        x->size = qMin(int(alloc) - 1, d->size);
+        x->alloc = alloc - 1u;
         x->capacityReserved = d->capacityReserved;
         x->offset = sizeof(QStringData);
         ::memcpy(x->data(), d->data(), x->size * sizeof(QChar));
@@ -1313,10 +1313,10 @@ void QString::reallocData(int alloc, bool grow)
             QString::free(d);
         d = x;
     } else {
-        Data *p = static_cast<Data *>(::realloc(d, sizeof(Data) + (alloc+1) * sizeof(QChar)));
+        Data *p = static_cast<Data *>(::realloc(d, sizeof(Data) + alloc * sizeof(QChar)));
         Q_CHECK_PTR(p);
         d = p;
-        d->alloc = alloc;
+        d->alloc = alloc - 1u;
         d->offset = sizeof(QStringData);
     }
 }
@@ -1525,7 +1525,7 @@ QString &QString::append(const QString &str)
             operator=(str);
         } else {
             if (d->ref.isShared() || d->size + str.d->size > int(d->alloc))
-                reallocData(d->size + str.d->size, true);
+                reallocData(uint(d->size + str.d->size) + 1u, true);
             memcpy(d->data() + d->size, str.d->data(), str.d->size * sizeof(QChar));
             d->size += str.d->size;
             d->data()[d->size] = '\0';
@@ -1545,7 +1545,7 @@ QString &QString::append(const QLatin1String &str)
     if (s) {
         int len = str.size();
         if (d->ref.isShared() || d->size + len > int(d->alloc))
-            reallocData(d->size + len, true);
+            reallocData(uint(d->size + len) + 1u, true);
         ushort *i = d->data() + d->size;
         while ((*i++ = *s++))
             ;
@@ -1588,7 +1588,7 @@ QString &QString::append(const QLatin1String &str)
 QString &QString::append(QChar ch)
 {
     if (d->ref.isShared() || d->size + 1 > int(d->alloc))
-        reallocData(d->size + 1, true);
+        reallocData(uint(d->size) + 2u, true);
     d->data()[d->size++] = ch.unicode();
     d->data()[d->size] = '\0';
     return *this;
@@ -2809,7 +2809,7 @@ QString& QString::replace(const QRegExp &rx, const QString &after)
     if (isEmpty() && rx2.indexIn(*this) == -1)
         return *this;
 
-    reallocData(d->size);
+    reallocData(uint(d->size) + 1u);
 
     int index = 0;
     int numCaptures = rx2.captureCount();
@@ -2972,7 +2972,7 @@ QString &QString::replace(const QRegularExpression &re, const QString &after)
     if (!iterator.hasNext()) // no matches at all
         return *this;
 
-    reallocData(d->size);
+    reallocData(uint(d->size) + 1u);
 
     int numCaptures = re.captureCount();
 
@@ -5076,7 +5076,7 @@ const ushort *QString::utf16() const
 {
     if (IS_RAW_DATA(d)) {
         // ensure '\0'-termination for ::fromRawData strings
-        const_cast<QString*>(this)->reallocData(d->size);
+        const_cast<QString*>(this)->reallocData(uint(d->size) + 1u);
     }
     return d->data();
 }
diff --git a/src/corelib/tools/qstring.h b/src/corelib/tools/qstring.h
index d09e3b5ab2..a902f5f375 100644
--- a/src/corelib/tools/qstring.h
+++ b/src/corelib/tools/qstring.h
@@ -370,7 +370,7 @@ public:
 
     inline QString &operator+=(QChar c) {
         if (d->ref.isShared() || d->size + 1 > int(d->alloc))
-            reallocData(d->size + 1, true);
+            reallocData(uint(d->size) + 2u, true);
         d->data()[d->size++] = c.unicode();
         d->data()[d->size] = '\0';
         return *this;
@@ -646,7 +646,7 @@ private:
     Data *d;
 
     static void free(Data *);
-    void reallocData(int alloc, bool grow = false);
+    void reallocData(uint alloc, bool grow = false);
     void expand(int i);
     void updateProperties() const;
     QString multiArg(int numArgs, const QString **args) const;
@@ -742,7 +742,7 @@ inline QChar *QString::data()
 inline const QChar *QString::constData() const
 { return reinterpret_cast<const QChar*>(d->data()); }
 inline void QString::detach()
-{ if (d->ref.isShared() || (d->offset != sizeof(QStringData))) reallocData(d->size); }
+{ if (d->ref.isShared() || (d->offset != sizeof(QStringData))) reallocData(uint(d->size) + 1u); }
 inline bool QString::isDetached() const
 { return !d->ref.isShared(); }
 inline QString &QString::operator=(const QLatin1String &s)
@@ -908,7 +908,7 @@ inline QString::~QString() { if (!d->ref.deref()) free(d); }
 inline void QString::reserve(int asize)
 {
     if (d->ref.isShared() || asize > int(d->alloc))
-        reallocData(asize);
+        reallocData(uint(asize) + 1u);
 
     if (!d->capacityReserved) {
         // cannot set unconditionally, since d could be the shared_null/shared_empty (which is const)
@@ -919,7 +919,7 @@ inline void QString::reserve(int asize)
 inline void QString::squeeze()
 {
     if (d->ref.isShared() || d->size < int(d->alloc))
-        reallocData(d->size);
+        reallocData(uint(d->size) + 1u);
 
     if (d->capacityReserved) {
         // cannot set unconditionally, since d could be shared_null or