tst_qfileinfo: Refactor ntfsJunctionPointsAndSymlinks()

Move the creation of the symbolic link/junction from the _data() slot
into the actual test function. The parameters are passed by a newly
introduced struct. This ensures only the symbolic links/junctions that
are actually needed are created. It can then no longer happen that
filtering for one data row invokes recursive deletion of the mountpoint
junction.

Also use of the newly introduced convenience createSymbolicLink()
in canonicalFilePath()

Task-number: QTBUG-63989
Change-Id: Ia78fd4ad6097136934ab5a375f4c352713d0f115
Reviewed-by: Orgad Shaneh <orgads@gmail.com>

tests/auto/corelib/io/qfileinfo/tst_qfileinfo.cpp

@@ -95,6 +95,38 @@ inline bool qIsLikelyToBeNfs(const QString &path)
 #endif
 }
 
+#if defined(Q_OS_WIN) && !defined(Q_OS_WINRT)
+#  ifndef SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE // MinGW
+#    define SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE (0x2)
+#  endif
+
+static DWORD createSymbolicLink(const QString &symLinkName, const QString &target,
+                                QString *errorMessage)
+{
+    DWORD result = ERROR_SUCCESS;
+    const QString nativeSymLinkName = QDir::toNativeSeparators(symLinkName);
+    const QString nativeTarget = QDir::toNativeSeparators(target);
+    DWORD flags = 0;
+    if (QOperatingSystemVersion::current() >= QOperatingSystemVersion(QOperatingSystemVersion::Windows, 10, 0, 14972))
+        flags |= SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE;
+    if (QFileInfo(target).isDir())
+        flags |= SYMBOLIC_LINK_FLAG_DIRECTORY;
+    if (CreateSymbolicLink(reinterpret_cast<const wchar_t*>(nativeSymLinkName.utf16()),
+                           reinterpret_cast<const wchar_t*>(nativeTarget.utf16()), flags) == FALSE) {
+        result = GetLastError();
+        QTextStream(errorMessage) << "CreateSymbolicLink(" <<  nativeSymLinkName << ", "
+            << nativeTarget << ", 0x" << hex << flags << dec << ") failed with error " << result
+            << ": " << qt_error_string(int(result));
+    }
+    return result;
+}
+
+static QByteArray msgInsufficientPrivileges(const QString &errorMessage)
+{
+    return "Insufficient privileges (" + errorMessage.toLocal8Bit() + ')';
+}
+#endif  // Q_OS_WIN && !Q_OS_WINRT
+
 static QString seedAndTemplate()
 {
     QString base;
@@ -704,19 +736,14 @@ void tst_QFileInfo::canonicalFilePath()
 
 #if defined(Q_OS_WIN) && !defined(Q_OS_WINRT)
     {
-        // CreateSymbolicLink can return TRUE & still fail to create the link,
+        QString errorMessage;
-        // the error code in that case is ERROR_PRIVILEGE_NOT_HELD (1314)
-        SetLastError(0);
         const QString linkTarget = QStringLiteral("res");
-        BOOL ret = CreateSymbolicLink((wchar_t*)linkTarget.utf16(), (wchar_t*)m_resourcesDir.utf16(), 1);
+        const DWORD dwErr = createSymbolicLink(linkTarget, m_resourcesDir, &errorMessage);
-        DWORD dwErr = GetLastError();
+        if (dwErr == ERROR_PRIVILEGE_NOT_HELD)
-        if (!ret)
+            QSKIP(msgInsufficientPrivileges(errorMessage));
-            QSKIP("Symbolic links aren't supported by FS");
+        QVERIFY2(dwErr == ERROR_SUCCESS, qPrintable(errorMessage));
         QString currentPath = QDir::currentPath();
-        bool is_res_Current = QDir::setCurrent(linkTarget);
+        QVERIFY(QDir::setCurrent(linkTarget));
-        if (!is_res_Current && dwErr == 1314)
-            QSKIP("Not enough privilages to create Symbolic links");
-        QCOMPARE(is_res_Current, true);
         const QString actualCanonicalPath = QFileInfo("file1").canonicalFilePath();
         QVERIFY(QDir::setCurrent(currentPath));
         QCOMPARE(actualCanonicalPath, m_resourcesDir + QStringLiteral("/file1"));
@@ -1455,8 +1482,24 @@ void tst_QFileInfo::refresh()
 }
 
 #if defined(Q_OS_WIN) && !defined(Q_OS_WINRT)
+
+struct NtfsTestResource {
+
+    enum Type { None, SymLink, Junction };
+
+    explicit NtfsTestResource(Type tp = None, const QString &s = QString(), const QString &t = QString())
+        : source(s), target(t), type(tp) {}
+
+    QString source;
+    QString target;
+    Type type;
+};
+
+Q_DECLARE_METATYPE(NtfsTestResource)
+
 void tst_QFileInfo::ntfsJunctionPointsAndSymlinks_data()
 {
+    QTest::addColumn<NtfsTestResource>("resource");
     QTest::addColumn<QString>("path");
     QTest::addColumn<bool>("isSymLink");
     QTest::addColumn<QString>("linkTarget");
@@ -1479,32 +1522,20 @@ void tst_QFileInfo::ntfsJunctionPointsAndSymlinks_data()
         QString fileInSymlink(absSymlink);
         fileInSymlink.append("\\file");
         QFile file(fileInTarget);
-        file.open(QIODevice::ReadWrite);
+        QVERIFY2(file.open(QIODevice::ReadWrite), qPrintable(file.errorString()));
         file.close();
 
-        DWORD err = ERROR_SUCCESS ;
-        if (!pwd.exists("abs_symlink"))
-            if (!CreateSymbolicLink((wchar_t*)absSymlink.utf16(),(wchar_t*)absTarget.utf16(),0x1))
-                err = GetLastError();
-        if (err == ERROR_SUCCESS && !pwd.exists(relSymlink))
-            if (!CreateSymbolicLink((wchar_t*)relSymlink.utf16(),(wchar_t*)relTarget.utf16(),0x1))
-                err = GetLastError();
-        if (err != ERROR_SUCCESS) {
-            wchar_t errstr[0x100];
-            DWORD count = FormatMessageW(FORMAT_MESSAGE_FROM_SYSTEM,
-                0, err, 0, errstr, 0x100, 0);
-            QString error(QString::fromWCharArray(errstr, count));
-            qWarning() << error;
-            //we need at least one data set for the test not to assert fail when skipping _data function
-            QDir target("target");
-            QTest::newRow("dummy") << target.path() << false << "" << target.canonicalPath();
-            QSKIP("link not supported by FS or insufficient privilege");
-        }
         QVERIFY2(file.exists(), msgDoesNotExist(file.fileName()).constData());
 
-        QTest::newRow("absolute dir symlink") << absSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalPath();
+        QTest::newRow("absolute dir symlink")
-        QTest::newRow("relative dir symlink") << relSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalPath();
+            << NtfsTestResource(NtfsTestResource::SymLink, absSymlink, absTarget)
-        QTest::newRow("file in symlink dir") << fileInSymlink << false << "" << target.canonicalPath().append("/file");
+            << absSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalPath();
+        QTest::newRow("relative dir symlink")
+            << NtfsTestResource(NtfsTestResource::SymLink, relSymlink, relTarget)
+            << relSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalPath();
+        QTest::newRow("file in symlink dir")
+            << NtfsTestResource()
+            << fileInSymlink << false << "" << target.canonicalPath().append("/file");
     }
     {
         //File symlinks
@@ -1517,33 +1548,41 @@ void tst_QFileInfo::ntfsJunctionPointsAndSymlinks_data()
         QString relSymlink = "rel_symlink.cpp";
         QString relToRelTarget = QDir::toNativeSeparators(relativeDir.relativeFilePath(target.absoluteFilePath()));
         QString relToRelSymlink = "relative/rel_symlink";
-        QVERIFY(pwd.exists("abs_symlink.cpp") || CreateSymbolicLink((wchar_t*)absSymlink.utf16(),(wchar_t*)absTarget.utf16(),0x0));
+
-        QVERIFY(pwd.exists(relSymlink) || CreateSymbolicLink((wchar_t*)relSymlink.utf16(),(wchar_t*)relTarget.utf16(),0x0));
+        QTest::newRow("absolute file symlink")
-        QVERIFY(pwd.exists(relToRelSymlink) || CreateSymbolicLink((wchar_t*)relToRelSymlink.utf16(), (wchar_t*)relToRelTarget.utf16(),0x0));
+            << NtfsTestResource(NtfsTestResource::SymLink, absSymlink, absTarget)
-        QTest::newRow("absolute file symlink") << absSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalFilePath();
+            << absSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalFilePath();
-        QTest::newRow("relative file symlink") << relSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalFilePath();
+        QTest::newRow("relative file symlink")
-        QTest::newRow("relative to relative file symlink") << relToRelSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalFilePath();
+            << NtfsTestResource(NtfsTestResource::SymLink, relSymlink, relTarget)
+            << relSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalFilePath();
+        QTest::newRow("relative to relative file symlink")
+            << NtfsTestResource(NtfsTestResource::SymLink, relToRelSymlink, relToRelTarget)
+            << relToRelSymlink << true << QDir::fromNativeSeparators(absTarget) << target.canonicalFilePath();
     }
 
     //Junctions
     QString target = "target";
     QString junction = "junction_pwd";
-    FileSystem::createNtfsJunction(target, junction);
     QFileInfo targetInfo(target);
-    QTest::newRow("junction_pwd") << junction << false << QString() << QString();
+    QTest::newRow("junction_pwd")
+        << NtfsTestResource(NtfsTestResource::Junction, junction, target)
+        << junction << false << QString() << QString();
 
     QFileInfo fileInJunction(targetInfo.absoluteFilePath().append("/file"));
     QFile file(fileInJunction.absoluteFilePath());
-    file.open(QIODevice::ReadWrite);
+    QVERIFY2(file.open(QIODevice::ReadWrite), qPrintable(file.errorString()));
     file.close();
     QVERIFY2(file.exists(), msgDoesNotExist(file.fileName()).constData());
-    QTest::newRow("file in junction") << fileInJunction.absoluteFilePath() << false << "" << fileInJunction.canonicalFilePath();
+    QTest::newRow("file in junction")
+        << NtfsTestResource()
+        << fileInJunction.absoluteFilePath() << false << QString() << fileInJunction.canonicalFilePath();
 
     target = QDir::rootPath();
     junction = "junction_root";
-    FileSystem::createNtfsJunction(target, junction);
     targetInfo.setFile(target);
-    QTest::newRow("junction_root") << junction << false << QString() << QString();
+    QTest::newRow("junction_root")
+        << NtfsTestResource(NtfsTestResource::Junction, junction, target)
+        << junction << false << QString() << QString();
 
     //Mountpoint
     wchar_t buffer[MAX_PATH];
@@ -1552,17 +1591,38 @@ void tst_QFileInfo::ntfsJunctionPointsAndSymlinks_data()
     QString rootVolume = QString::fromWCharArray(buffer);
     junction = "mountpoint";
     rootVolume.replace("\\\\?\\","\\??\\");
-    FileSystem::createNtfsJunction(rootVolume, junction);
+    QTest::newRow("mountpoint")
-    QTest::newRow("mountpoint") << junction << false << QString() << QString();
+        << NtfsTestResource(NtfsTestResource::Junction, junction, rootVolume)
+        << junction << false << QString() << QString();
 }
 
 void tst_QFileInfo::ntfsJunctionPointsAndSymlinks()
 {
+    QFETCH(NtfsTestResource, resource);
     QFETCH(QString, path);
     QFETCH(bool, isSymLink);
     QFETCH(QString, linkTarget);
     QFETCH(QString, canonicalFilePath);
 
+    QString errorMessage;
+    DWORD creationResult = ERROR_SUCCESS;
+    switch (resource.type) {
+    case NtfsTestResource::None:
+        break;
+    case NtfsTestResource::SymLink:
+        creationResult = createSymbolicLink(resource.source, resource.target, &errorMessage);
+        break;
+    case NtfsTestResource::Junction:
+        creationResult = FileSystem::createNtfsJunction(resource.target, resource.source, &errorMessage);
+        if (creationResult == ERROR_NOT_SUPPORTED) // Special value indicating non-NTFS drive
+            QSKIP(qPrintable(errorMessage));
+        break;
+    }
+
+    if (creationResult == ERROR_PRIVILEGE_NOT_HELD)
+        QSKIP(msgInsufficientPrivileges(errorMessage));
+    QVERIFY2(creationResult == ERROR_SUCCESS, qPrintable(errorMessage));
+
     QFileInfo fi(path);
     const bool actualIsSymLink = fi.isSymLink();
     const QString actualSymLinkTarget = isSymLink ? fi.symLinkTarget() : QString();

tests/benchmarks/corelib/io/qfileinfo/main.cpp

@@ -94,7 +94,9 @@ void qfileinfo::symLinkTargetPerformanceMounpoint()
     QString rootVolume = QString::fromWCharArray(buffer);
     QString mountpoint = "mountpoint";
     rootVolume.replace("\\\\?\\","\\??\\");
-    FileSystem::createNtfsJunction(rootVolume, mountpoint);
+    QString errorMessage;
+    QVERIFY2(FileSystem::createNtfsJunction(rootVolume, mountpoint, &errorMessage) == ERROR_SUCCESS,
+             qPrintable(errorMessage));
 
     QFileInfo info(mountpoint);
     info.setCaching(false);

tests/shared/filesystem.h

@@ -80,7 +80,7 @@ public:
     }
 
 #if defined(Q_OS_WIN) && !defined(Q_OS_WINCE) && !defined(Q_OS_WINRT)
-    static void createNtfsJunction(QString target, QString linkName)
+    static DWORD createNtfsJunction(QString target, QString linkName, QString *errorMessage)
     {
         typedef struct {
             DWORD   ReparseTag;
@@ -97,14 +97,22 @@ public:
         DWORD   returnedLength;
         wchar_t fileSystem[MAX_PATH] = L"";
         PREPARSE_MOUNTPOINT_DATA_BUFFER reparseInfo = (PREPARSE_MOUNTPOINT_DATA_BUFFER) reparseBuffer;
+        DWORD result = ERROR_SUCCESS;
 
         QFileInfo junctionInfo(linkName);
         linkName = QDir::toNativeSeparators(junctionInfo.absoluteFilePath());
-
+        const QString drive = linkName.left(3);
-        GetVolumeInformationW( (wchar_t*)linkName.left(3).utf16(), NULL, 0, NULL, NULL, NULL,
+        if (GetVolumeInformationW(reinterpret_cast<const wchar_t *>(drive.utf16()),
-                               fileSystem, sizeof(fileSystem)/sizeof(WCHAR));
+                                  NULL, 0, NULL, NULL, NULL,
-        if(QString().fromWCharArray(fileSystem) != "NTFS")
+                                  fileSystem, sizeof(fileSystem)/sizeof(WCHAR)) == FALSE) {
-            QSKIP("This seems not to be an NTFS volume. Junctions are not allowed.");
+            result = GetLastError();
+            *errorMessage = "GetVolumeInformationW() failed: " + qt_error_string(int(result));
+            return result;
+        }
+        if (QString::fromWCharArray(fileSystem) != "NTFS") {
+            *errorMessage = "This seems not to be an NTFS volume. Junctions are not allowed.";
+            return ERROR_NOT_SUPPORTED;
+        }
 
         if (!target.startsWith("\\??\\") && !target.startsWith("\\\\?\\")) {
             QFileInfo targetInfo(target);
@@ -116,7 +124,11 @@ public:
         QDir().mkdir(linkName);
         hFile = CreateFileW( (wchar_t*)linkName.utf16(), GENERIC_WRITE, 0, NULL, OPEN_EXISTING,
                              FILE_FLAG_OPEN_REPARSE_POINT|FILE_FLAG_BACKUP_SEMANTICS, NULL );
-        QVERIFY(hFile != INVALID_HANDLE_VALUE );
+        if (hFile == INVALID_HANDLE_VALUE) {
+            result = GetLastError();
+            *errorMessage = "CreateFileW(" + linkName + ") failed: " + qt_error_string(int(result));
+            return result;
+        }
 
         memset( reparseInfo, 0, sizeof( *reparseInfo ));
         reparseInfo->ReparseTag = IO_REPARSE_TAG_MOUNT_POINT;
@@ -128,8 +140,12 @@ public:
         bool ioc = DeviceIoControl(hFile, FSCTL_SET_REPARSE_POINT, reparseInfo,
                                  reparseInfo->ReparseDataLength + REPARSE_MOUNTPOINT_HEADER_SIZE,
                                  NULL, 0, &returnedLength, NULL);
+        if (!ioc) {
+            result = GetLastError();
+            *errorMessage = "DeviceIoControl() failed: " + qt_error_string(int(result));
+        }
         CloseHandle( hFile );
-        QVERIFY(ioc);
+        return result;
     }
 #endif