Clean up QTextBoundaryFinder and qunicodetools

Make QTBF ready for Qt6 by using qsizetype in the API and use
QStringView where it makes sense.

Change the exported API of qunicodetools to use QStringView as
well and use char16_t internally.

Change-Id: I853537bcabf40546a8e60fdf2ee7d751bc371761
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

1 files changed, 81 insertions, 93 deletions

diff --git a/src/corelib/text/qtextboundaryfinder.cpp b/src/corelib/text/qtextboundaryfinder.cpp
index fdbb7f0176..dd0b96ed68 100644
--- a/src/corelib/text/qtextboundaryfinder.cpp
+++ b/src/corelib/text/qtextboundaryfinder.cpp
@@ -43,18 +43,10 @@
 
 QT_BEGIN_NAMESPACE
 
-class QTextBoundaryFinderPrivate
+static void init(QTextBoundaryFinder::BoundaryType type, QStringView str, QCharAttributes *attributes)
 {
-public:
-    QCharAttributes attributes[1];
-};
-
-static void init(QTextBoundaryFinder::BoundaryType type, const QChar *chars, int length, QCharAttributes *attributes)
-{
-    const ushort *string = reinterpret_cast<const ushort *>(chars);
-
     QUnicodeTools::ScriptItemArray scriptItems;
-    QUnicodeTools::initScripts(string, length, &scriptItems);
+    QUnicodeTools::initScripts(str, &scriptItems);
 
     QUnicodeTools::CharAttributeOptions options;
     switch (type) {
@@ -64,7 +56,7 @@ static void init(QTextBoundaryFinder::BoundaryType type, const QChar *chars, int
     case QTextBoundaryFinder::Line: options |= QUnicodeTools::LineBreaks; break;
     default: break;
     }
-    QUnicodeTools::initCharAttributes(string, length, scriptItems.data(), scriptItems.count(), attributes, options);
+    QUnicodeTools::initCharAttributes(str, scriptItems.data(), scriptItems.count(), attributes, options);
 }
 
 /*!
@@ -145,11 +137,7 @@ static void init(QTextBoundaryFinder::BoundaryType type, const QChar *chars, int
   Constructs an invalid QTextBoundaryFinder object.
 */
 QTextBoundaryFinder::QTextBoundaryFinder()
-    : t(Grapheme)
-    , chars(nullptr)
-    , length(0)
-    , freePrivate(true)
-    , d(nullptr)
+    : freeBuffer(true)
 {
 }
 
@@ -159,17 +147,15 @@ QTextBoundaryFinder::QTextBoundaryFinder()
 QTextBoundaryFinder::QTextBoundaryFinder(const QTextBoundaryFinder &other)
     : t(other.t)
     , s(other.s)
-    , chars(other.chars)
-    , length(other.length)
+    , sv(other.sv)
     , pos(other.pos)
-    , freePrivate(true)
-    , d(nullptr)
+    , freeBuffer(true)
 {
-    if (other.d) {
-        Q_ASSERT(length > 0);
-        d = (QTextBoundaryFinderPrivate *) malloc((length + 1) * sizeof(QCharAttributes));
-        Q_CHECK_PTR(d);
-        memcpy(d, other.d, (length + 1) * sizeof(QCharAttributes));
+    if (other.attributes) {
+        Q_ASSERT(sv.size() > 0);
+        attributes = (QCharAttributes *) malloc((sv.size() + 1) * sizeof(QCharAttributes));
+        Q_CHECK_PTR(attributes);
+        memcpy(attributes, other.attributes, (sv.size() + 1) * sizeof(QCharAttributes));
     }
 }
 
@@ -181,27 +167,26 @@ QTextBoundaryFinder &QTextBoundaryFinder::operator=(const QTextBoundaryFinder &o
     if (&other == this)
         return *this;
 
-    if (other.d) {
-        Q_ASSERT(other.length > 0);
-        uint newCapacity = (other.length + 1) * sizeof(QCharAttributes);
-        QTextBoundaryFinderPrivate *newD = (QTextBoundaryFinderPrivate *) realloc(freePrivate ? d : nullptr, newCapacity);
+    if (other.attributes) {
+        Q_ASSERT(other.sv.size() > 0);
+        size_t newCapacity = (size_t(other.sv.size()) + 1) * sizeof(QCharAttributes);
+        QCharAttributes *newD = (QCharAttributes *) realloc(freeBuffer ? attributes : nullptr, newCapacity);
         Q_CHECK_PTR(newD);
-        freePrivate = true;
-        d = newD;
+        freeBuffer = true;
+        attributes = newD;
     }
 
     t = other.t;
     s = other.s;
-    chars = other.chars;
-    length = other.length;
+    sv = other.sv;
     pos = other.pos;
 
-    if (other.d) {
-        memcpy(d, other.d, (length + 1) * sizeof(QCharAttributes));
+    if (other.attributes) {
+        memcpy(attributes, other.attributes, (sv.size() + 1) * sizeof(QCharAttributes));
     } else {
-        if (freePrivate)
-            free(d);
-        d = nullptr;
+        if (freeBuffer)
+            free(attributes);
+        attributes = nullptr;
     }
 
     return *this;
@@ -213,8 +198,8 @@ QTextBoundaryFinder &QTextBoundaryFinder::operator=(const QTextBoundaryFinder &o
 QTextBoundaryFinder::~QTextBoundaryFinder()
 {
     Q_UNUSED(unused);
-    if (freePrivate)
-        free(d);
+    if (freeBuffer)
+        free(attributes);
 }
 
 /*!
@@ -223,22 +208,28 @@ QTextBoundaryFinder::~QTextBoundaryFinder()
 QTextBoundaryFinder::QTextBoundaryFinder(BoundaryType type, const QString &string)
     : t(type)
     , s(string)
-    , chars(string.unicode())
-    , length(string.length())
+    , sv(s)
     , pos(0)
-    , freePrivate(true)
-    , d(nullptr)
+    , freeBuffer(true)
+    , attributes(nullptr)
 {
-    if (length > 0) {
-        d = (QTextBoundaryFinderPrivate *) malloc((length + 1) * sizeof(QCharAttributes));
-        Q_CHECK_PTR(d);
-        init(t, chars, length, d->attributes);
+    if (sv.size() > 0) {
+        attributes = (QCharAttributes *) malloc((sv.size() + 1) * sizeof(QCharAttributes));
+        Q_CHECK_PTR(attributes);
+        init(t, sv, attributes);
     }
 }
 
 /*!
-  Creates a QTextBoundaryFinder object of \a type operating on \a chars
-  with \a length.
+  \fn QTextBoundaryFinder::QTextBoundaryFinder(BoundaryType type, const QChar *chars, qsizetype length, unsigned char *buffer, qsizetype bufferSize)
+  \overload
+
+  The same as QTextBoundaryFinder(type, QStringView(chars, length), buffer, bufferSize).
+*/
+
+/*!
+  Creates a QTextBoundaryFinder object of \a type operating on \a string.
+  \since 6.0
 
   \a buffer is an optional working buffer of size \a bufferSize you can pass to
   the QTextBoundaryFinder. If the buffer is large enough to hold the working
@@ -250,25 +241,22 @@ QTextBoundaryFinder::QTextBoundaryFinder(BoundaryType type, const QString &strin
   as long as the QTextBoundaryFinder object stays alive. The same applies to
   \a buffer.
 */
-QTextBoundaryFinder::QTextBoundaryFinder(BoundaryType type, const QChar *chars, int length, unsigned char *buffer, int bufferSize)
+QTextBoundaryFinder::QTextBoundaryFinder(BoundaryType type, QStringView string, unsigned char *buffer, qsizetype bufferSize)
     : t(type)
-    , chars(chars)
-    , length(length)
+    , sv(string)
     , pos(0)
-    , freePrivate(true)
-    , d(nullptr)
+    , freeBuffer(true)
+    , attributes(nullptr)
 {
-    if (!chars) {
-        length = 0;
-    } else if (length > 0) {
-        if (buffer && (uint)bufferSize >= (length + 1) * sizeof(QCharAttributes)) {
-            d = (QTextBoundaryFinderPrivate *)buffer;
-            freePrivate = false;
+    if (!sv.isEmpty()) {
+        if (buffer && (uint)bufferSize >= (sv.size() + 1) * sizeof(QCharAttributes)) {
+            attributes = reinterpret_cast<QCharAttributes *>(buffer);
+            freeBuffer = false;
         } else {
-            d = (QTextBoundaryFinderPrivate *) malloc((length + 1) * sizeof(QCharAttributes));
-            Q_CHECK_PTR(d);
+            attributes = (QCharAttributes *) malloc((sv.size() + 1) * sizeof(QCharAttributes));
+            Q_CHECK_PTR(attributes);
         }
-        init(t, chars, length, d->attributes);
+        init(t, sv, attributes);
     }
 }
 
@@ -289,7 +277,7 @@ void QTextBoundaryFinder::toStart()
 */
 void QTextBoundaryFinder::toEnd()
 {
-    pos = length;
+    pos = sv.size();
 }
 
 /*!
@@ -300,7 +288,7 @@ void QTextBoundaryFinder::toEnd()
 
   \sa setPosition()
 */
-int QTextBoundaryFinder::position() const
+qsizetype QTextBoundaryFinder::position() const
 {
     return pos;
 }
@@ -314,9 +302,9 @@ int QTextBoundaryFinder::position() const
 
   \sa position()
 */
-void QTextBoundaryFinder::setPosition(int position)
+void QTextBoundaryFinder::setPosition(qsizetype position)
 {
-    pos = qBound(0, position, length);
+    pos = qBound(0, position, sv.size());
 }
 
 /*! \fn QTextBoundaryFinder::BoundaryType QTextBoundaryFinder::type() const
@@ -335,9 +323,9 @@ void QTextBoundaryFinder::setPosition(int position)
 */
 QString QTextBoundaryFinder::string() const
 {
-    if (chars == s.unicode() && length == s.length())
+    if (sv.data() == s.unicode() && sv.size() == s.size())
         return s;
-    return QString(chars, length);
+    return sv.toString();
 }
 
 
@@ -346,9 +334,9 @@ QString QTextBoundaryFinder::string() const
 
   Returns -1 if there is no next boundary.
 */
-int QTextBoundaryFinder::toNextBoundary()
+qsizetype QTextBoundaryFinder::toNextBoundary()
 {
-    if (!d || pos < 0 || pos >= length) {
+    if (!attributes || pos < 0 || pos >= sv.size()) {
         pos = -1;
         return pos;
     }
@@ -356,19 +344,19 @@ int QTextBoundaryFinder::toNextBoundary()
     ++pos;
     switch(t) {
     case Grapheme:
-        while (pos < length && !d->attributes[pos].graphemeBoundary)
+        while (pos < sv.size() && !attributes[pos].graphemeBoundary)
             ++pos;
         break;
     case Word:
-        while (pos < length && !d->attributes[pos].wordBreak)
+        while (pos < sv.size() && !attributes[pos].wordBreak)
             ++pos;
         break;
     case Sentence:
-        while (pos < length && !d->attributes[pos].sentenceBoundary)
+        while (pos < sv.size() && !attributes[pos].sentenceBoundary)
             ++pos;
         break;
     case Line:
-        while (pos < length && !d->attributes[pos].lineBreak)
+        while (pos < sv.size() && !attributes[pos].lineBreak)
             ++pos;
         break;
     }
@@ -381,9 +369,9 @@ int QTextBoundaryFinder::toNextBoundary()
 
   Returns -1 if there is no previous boundary.
 */
-int QTextBoundaryFinder::toPreviousBoundary()
+qsizetype QTextBoundaryFinder::toPreviousBoundary()
 {
-    if (!d || pos <= 0 || pos > length) {
+    if (!attributes || pos <= 0 || pos > sv.size()) {
         pos = -1;
         return pos;
     }
@@ -391,19 +379,19 @@ int QTextBoundaryFinder::toPreviousBoundary()
     --pos;
     switch(t) {
     case Grapheme:
-        while (pos > 0 && !d->attributes[pos].graphemeBoundary)
+        while (pos > 0 && !attributes[pos].graphemeBoundary)
             --pos;
         break;
     case Word:
-        while (pos > 0 && !d->attributes[pos].wordBreak)
+        while (pos > 0 && !attributes[pos].wordBreak)
             --pos;
         break;
     case Sentence:
-        while (pos > 0 && !d->attributes[pos].sentenceBoundary)
+        while (pos > 0 && !attributes[pos].sentenceBoundary)
             --pos;
         break;
     case Line:
-        while (pos > 0 && !d->attributes[pos].lineBreak)
+        while (pos > 0 && !attributes[pos].lineBreak)
             --pos;
         break;
     }
@@ -416,19 +404,19 @@ int QTextBoundaryFinder::toPreviousBoundary()
 */
 bool QTextBoundaryFinder::isAtBoundary() const
 {
-    if (!d || pos < 0 || pos > length)
+    if (!attributes || pos < 0 || pos > sv.size())
         return false;
 
     switch(t) {
     case Grapheme:
-        return d->attributes[pos].graphemeBoundary;
+        return attributes[pos].graphemeBoundary;
     case Word:
-        return d->attributes[pos].wordBreak;
+        return attributes[pos].wordBreak;
     case Sentence:
-        return d->attributes[pos].sentenceBoundary;
+        return attributes[pos].sentenceBoundary;
     case Line:
         // ### TR#14 LB2 prohibits break at sot
-        return d->attributes[pos].lineBreak || pos == 0;
+        return attributes[pos].lineBreak || pos == 0;
     }
     return false;
 }
@@ -439,17 +427,17 @@ bool QTextBoundaryFinder::isAtBoundary() const
 QTextBoundaryFinder::BoundaryReasons QTextBoundaryFinder::boundaryReasons() const
 {
     BoundaryReasons reasons = NotAtBoundary;
-    if (!d || pos < 0 || pos > length)
+    if (!attributes || pos < 0 || pos > sv.size())
         return reasons;
 
-    const QCharAttributes attr = d->attributes[pos];
+    const QCharAttributes attr = attributes[pos];
     switch (t) {
     case Grapheme:
         if (attr.graphemeBoundary) {
             reasons |= BreakOpportunity | StartOfItem | EndOfItem;
             if (pos == 0)
                 reasons &= (~EndOfItem);
-            else if (pos == length)
+            else if (pos == sv.size())
                 reasons &= (~StartOfItem);
         }
         break;
@@ -467,7 +455,7 @@ QTextBoundaryFinder::BoundaryReasons QTextBoundaryFinder::boundaryReasons() cons
             reasons |= BreakOpportunity | StartOfItem | EndOfItem;
             if (pos == 0)
                 reasons &= (~EndOfItem);
-            else if (pos == length)
+            else if (pos == sv.size())
                 reasons &= (~StartOfItem);
         }
         break;
@@ -479,9 +467,9 @@ QTextBoundaryFinder::BoundaryReasons QTextBoundaryFinder::boundaryReasons() cons
                 reasons |= MandatoryBreak | StartOfItem | EndOfItem;
                 if (pos == 0)
                     reasons &= (~EndOfItem);
-                else if (pos == length)
+                else if (pos == sv.size())
                     reasons &= (~StartOfItem);
-            } else if (pos > 0 && chars[pos - 1].unicode() == QChar::SoftHyphen) {
+            } else if (pos > 0 && sv[pos - 1].unicode() == QChar::SoftHyphen) {
                 reasons |= SoftHyphen;
             }
         }