QDir: change qt_{cleanPath,normalizePathSegments} to returning bool

Since qt_normalizePathSegments very often modifies the path, pass that
as pointer, and return a boolean with whether the path is attempting to
go up above the root.

Change-Id: I851fcb94db4606a6bd97fffd81910930dea8222a
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: David Faure <david.faure@kdab.com>
(cherry picked from commit 0314491abac092b20ebefc05e2e9f27fd038fc38)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/corelib/io/qdir.cpp

@@ -970,7 +970,7 @@ QString QDir::fromNativeSeparators(const QString &pathName)
 #endif
 }
 
-static QString qt_cleanPath(const QString &path, bool *ok = nullptr);
+static bool qt_cleanPath(QString *path);
 
 /*!
     Changes the QDir's directory to \a dirName.
@@ -992,7 +992,8 @@ bool QDir::cd(const QString &dirName)
         return true;
     QString newPath;
     if (isAbsolutePath(dirName)) {
-        newPath = qt_cleanPath(dirName);
+        newPath = dirName;
+        qt_cleanPath(&newPath);
     } else {
         newPath = d->dirEntry.filePath();
         if (!newPath.endsWith(u'/'))
@@ -1001,9 +1002,7 @@ bool QDir::cd(const QString &dirName)
         if (dirName.indexOf(u'/') >= 0
             || dirName == ".."_L1
             || d->dirEntry.filePath() == u'.') {
-            bool ok;
-            newPath = qt_cleanPath(newPath, &ok);
-            if (!ok)
+            if (!qt_cleanPath(&newPath))
                 return false;
             /*
               If newPath starts with .., we convert it to absolute to
@@ -2358,25 +2357,15 @@ bool qt_normalizePathSegments(QString *path, QDirPrivate::PathNormalizations fla
     return ok || prefixLength == 0;
 }
 
-QString qt_normalizePathSegments(const QString &name, QDirPrivate::PathNormalizations flags, bool *ok)
+static bool qt_cleanPath(QString *path)
 {
-    // temporary compat
-    QString copy = name;
-    bool r = qt_normalizePathSegments(&copy, flags);
-    if (ok)
-        *ok = r;
-    return copy;
-}
+    if (path->isEmpty())
+        return true;
 
-static QString qt_cleanPath(const QString &path, bool *ok)
-{
-    if (path.isEmpty()) {
-        Q_ASSERT(!ok); // The only caller passing ok knows its path is non-empty
-        return path;
-    }
-
-    QString name = QDir::fromNativeSeparators(path);
-    QString ret = qt_normalizePathSegments(name, OSSupportsUncPaths ? QDirPrivate::AllowUncPaths : QDirPrivate::DefaultNormalization, ok);
+    QString &ret = *path;
+    ret = QDir::fromNativeSeparators(ret);
+    auto normalization = OSSupportsUncPaths ? QDirPrivate::AllowUncPaths : QDirPrivate::DefaultNormalization;
+    bool ok = qt_normalizePathSegments(&ret, normalization);
 
     // Strip away last slash except for root directories
     if (ret.size() > 1 && ret.endsWith(u'/')) {
@@ -2386,7 +2375,7 @@ static QString qt_cleanPath(const QString &path, bool *ok)
             ret.chop(1);
     }
 
-    return ret;
+    return ok;
 }
 
 /*!
@@ -2403,7 +2392,9 @@ static QString qt_cleanPath(const QString &path, bool *ok)
 */
 QString QDir::cleanPath(const QString &path)
 {
-    return qt_cleanPath(path);
+    QString ret = path;
+    qt_cleanPath(&ret);
+    return ret;
 }
 
 /*!

src/corelib/io/qdir_p.h

@@ -80,8 +80,7 @@ public:
 
 Q_DECLARE_OPERATORS_FOR_FLAGS(QDirPrivate::PathNormalizations)
 
-Q_AUTOTEST_EXPORT QString qt_normalizePathSegments(const QString &name, QDirPrivate::PathNormalizations flags, bool *ok = nullptr);
-bool qt_normalizePathSegments(QString *path, QDirPrivate::PathNormalizations flags);
+Q_AUTOTEST_EXPORT bool qt_normalizePathSegments(QString *path, QDirPrivate::PathNormalizations flags);
 
 QT_END_NAMESPACE
 

tests/auto/corelib/io/qdir/tst_qdir.cpp

@@ -1453,8 +1453,8 @@ void tst_QDir::normalizePathSegments()
     QFETCH(UncHandling, uncHandling);
     QFETCH(QString, expected);
     // for QDirPrivate::RemotePath, see tst_QUrl::resolving
-    QString cleaned = qt_normalizePathSegments(path, uncHandling == HandleUnc ? QDirPrivate::AllowUncPaths : QDirPrivate::DefaultNormalization);
-    QCOMPARE(cleaned, expected);
+    qt_normalizePathSegments(&path, uncHandling == HandleUnc ? QDirPrivate::AllowUncPaths : QDirPrivate::DefaultNormalization);
+    QCOMPARE(path, expected);
 }
 # endif //QT_BUILD_INTERNAL