Unify behavior for long path or UNC prefix removal

Split the code out of QDir::fromNativeSeparator into a separate
reusable function to remove the above-mentioned prefixes. Fixes
and unifies behavior if the prefix was given with slashes instead
of backslashes. Add a couple more test cases.

Fixes: QTBUG-93868
Change-Id: Ibd94ae283e2fb113f9c2db97475fbc7d89522bbf
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
(cherry picked from commit 0564ebdb3641d7325f73dbbf2cbb04e6dca92d83)
This commit is contained in:
Karsten Heimrich 2021-06-08 11:59:59 +02:00
parent e99a9ff495
commit 915dd3166a
9 changed files with 101 additions and 46 deletions

View File

@ -953,35 +953,10 @@ QString QDir::toNativeSeparators(const QString &pathName)
QString QDir::fromNativeSeparators(const QString &pathName)
{
#if defined(Q_OS_WIN)
const QChar nativeSeparator = u'\\';
int i = pathName.indexOf(nativeSeparator);
if (i != -1) {
QString n(pathName);
const QStringView uncPrefix(uR"(\\?\UNC\)");
const QStringView extendedLengthPathPrefix(uR"(\\?\)");
if (n.startsWith(uncPrefix)) {
// Keep the initial double-slash, chop out the rest of the prefix.
n = n.remove(2, uncPrefix.size() - 2);
if ((i = n.indexOf(nativeSeparator)) == -1)
return n;
} else if (n.startsWith(extendedLengthPathPrefix)) {
n = n.sliced(extendedLengthPathPrefix.size());
if ((i = n.indexOf(nativeSeparator)) == -1)
return n;
}
QChar * const data = n.data();
data[i++] = u'/';
for (; i < n.length(); ++i) {
if (data[i] == nativeSeparator)
data[i] = u'/';
}
return n;
}
#endif
return QFileSystemEntry::removeUncOrLongPathPrefix(pathName).replace(u'\\', u'/');
#else
return pathName;
#endif
}
static QString qt_cleanPath(const QString &path, bool *ok = nullptr);

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@ -297,18 +297,8 @@ static QString readSymLink(const QFileSystemEntry &link)
const wchar_t* PathBuffer = &rdb->SymbolicLinkReparseBuffer.PathBuffer[offset];
result = QString::fromWCharArray(PathBuffer, length);
}
// cut-off "\\?\" and "\??\"
if (result.size() > 4
&& result.at(0) == QLatin1Char('\\')
&& result.at(2) == QLatin1Char('?')
&& result.at(3) == QLatin1Char('\\')) {
result = result.mid(4);
// cut off UNC in addition when the link points at a UNC share
// in which case we need to prepend another backslash to get \\server\share
if (QStringView{result}.left(3) == QLatin1String("UNC")) {
result.replace(0, 3, QLatin1Char('\\'));
}
}
// remove "\\?\", "\??\" or "\\?\UNC\"
result = QFileSystemEntry::removeUncOrLongPathPrefix(result);
}
free(rdb);
CloseHandle(handle);

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@ -290,6 +290,34 @@ bool QFileSystemEntry::isDriveRootPath(const QString &path)
&& path.at(0).isLetter() && path.at(1) == QLatin1Char(':')
&& path.at(2) == QLatin1Char('/'));
}
QString QFileSystemEntry::removeUncOrLongPathPrefix(QString path)
{
constexpr qsizetype minPrefixSize = 4;
if (path.size() < minPrefixSize)
return path;
auto data = path.data();
const auto slash = path[0];
if (slash != u'\\' && slash != u'/')
return path;
// check for "//?/" or "/??/"
if (data[2] == u'?' && data[3] == slash && (data[1] == slash || data[1] == u'?')) {
path = path.sliced(minPrefixSize);
// check for a possible "UNC/" prefix left-over
if (path.size() >= 4) {
data = path.data();
if (data[0] == u'U' && data[1] == u'N' && data[2] == u'C' && data[3] == slash) {
data[2] = slash;
return path.sliced(2);
}
}
}
return path;
}
#endif // Q_OS_WIN
bool QFileSystemEntry::isRootPath(const QString &path)

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@ -95,6 +95,7 @@ public:
#if defined(Q_OS_WIN)
bool isDriveRoot() const;
static bool isDriveRootPath(const QString &path);
static QString removeUncOrLongPathPrefix(QString path);
#endif
bool isRoot() const;

View File

@ -1268,9 +1268,20 @@ tst_QDir::cleanPath_data()
QTest::newRow("drive-above-root") << "A:/.." << "A:/..";
QTest::newRow("unc-server-up") << "//server/path/.." << "//server";
QTest::newRow("unc-server-above-root") << "//server/.." << "//server/..";
QTest::newRow("longpath") << "\\\\?\\d:\\" << "d:/";
QTest::newRow("longpath-slash") << "//?/d:/" << "d:/";
QTest::newRow("longpath-mixed-slashes") << "//?/d:\\" << "d:/";
QTest::newRow("longpath-mixed-slashes-2") << "\\\\?\\d:/" << "d:/";
QTest::newRow("unc-network-share") << "\\\\?\\UNC\\localhost\\c$\\tmp.txt"
<< "//localhost/c$/tmp.txt";
QTest::newRow("unc-network-share-slash") << "//?/UNC/localhost/c$/tmp.txt"
<< "//localhost/c$/tmp.txt";
QTest::newRow("unc-network-share-mixed-slashes") << "//?/UNC/localhost\\c$\\tmp.txt"
<< "//localhost/c$/tmp.txt";
QTest::newRow("unc-network-share-mixed-slashes-2") << "\\\\?\\UNC\\localhost/c$/tmp.txt"
<< "//localhost/c$/tmp.txt";
#else
QTest::newRow("data15") << "//c:/foo" << "/c:/foo";
#endif // non-windows
@ -1748,6 +1759,8 @@ void tst_QDir::nativeSeparators()
QCOMPARE(QDir::fromNativeSeparators(QLatin1String("\\\\?\\C:\\")), QString("C:/"));
QCOMPARE(QDir::fromNativeSeparators(QLatin1String(R"(\\?\UNC\localhost\c$\tmp.txt)")),
QString("//localhost/c$/tmp.txt"));
QCOMPARE(QDir::fromNativeSeparators(QLatin1String(R"(//?/UNC/localhost\c$\tmp.txt)")),
QString("//localhost/c$/tmp.txt"));
#else
QCOMPARE(QDir::toNativeSeparators(QLatin1String("/")), QString("/"));
QCOMPARE(QDir::toNativeSeparators(QLatin1String("\\")), QString("\\"));

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@ -10,3 +10,8 @@ qt_internal_add_test(tst_qtemporarydir
PUBLIC_LIBRARIES
Qt::TestPrivate
)
qt_internal_extend_target(tst_qtemporarydir CONDITION WIN32
LIBRARIES
shlwapi
)

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@ -37,6 +37,7 @@
#include <qset.h>
#include <QtTest/private/qtesthelpers_p.h>
#ifdef Q_OS_WIN
# include <shlwapi.h>
# include <windows.h>
#endif
#ifdef Q_OS_UNIX // for geteuid()
@ -159,9 +160,25 @@ void tst_QTemporaryDir::fileTemplate_data()
}
#ifdef Q_OS_WIN
const auto tmp = QDir::toNativeSeparators(QDir::tempPath()).sliced(QDir::rootPath().size());
QTest::newRow("UNC") << "\\\\localhost\\C$\\" + tmp + "\\UNC.XXXXXX.tmpDir"
<< "UNC." << ".tmpDir";
auto tmp = QDir::toNativeSeparators(QDir::tempPath());
if (PathGetDriveNumber((const wchar_t *) tmp.utf16()) < 0)
return; // skip if we have no drive letter
tmp.data()[1] = u'$';
const auto tmpPath = tmp + QLatin1String(R"(\UNC.XXXXXX.tmpDir)");
QTest::newRow("UNC-backslash")
<< "\\\\localhost\\" + tmpPath << "UNC."
<< ".tmpDir";
QTest::newRow("UNC-prefix")
<< "\\\\?\\UNC\\localhost\\" + tmpPath << "UNC."
<< ".tmpDir";
QTest::newRow("UNC-slash")
<< "//localhost/" + QDir::fromNativeSeparators(tmpPath) << "UNC."
<< ".tmpDir";
QTest::newRow("UNC-prefix-slash")
<< "//?/UNC/localhost/" + QDir::fromNativeSeparators(tmpPath) << "UNC."
<< ".tmpDir";
#endif
}

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@ -45,3 +45,8 @@ if(ANDROID AND NOT ANDROID_EMBEDDED)
${android_testdata_resource_files}
)
endif()
qt_internal_extend_target(tst_qtemporaryfile CONDITION WIN32
LIBRARIES
shlwapi
)

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@ -40,6 +40,7 @@
#include <QtTest/private/qtesthelpers_p.h>
#if defined(Q_OS_WIN)
# include <shlwapi.h>
# include <windows.h>
#endif
#if defined(Q_OS_UNIX)
@ -208,9 +209,29 @@ void tst_QTemporaryFile::fileTemplate_data()
}
#ifdef Q_OS_WIN
const auto tmp = QDir::toNativeSeparators(QDir::tempPath()).sliced(QDir::rootPath().size());
QTest::newRow("UNC") << "\\\\localhost\\C$\\" + tmp + "\\QTBUG-74291.XXXXXX.tmpFile"
<< "QTBUG-74291." << ".tmpFile" << "";
auto tmp = QDir::toNativeSeparators(QDir::tempPath());
if (PathGetDriveNumber((const wchar_t *) tmp.utf16()) < 0)
return; // skip if we have no drive letter
tmp.data()[1] = u'$';
const auto tmpPath = tmp + QLatin1String(R"(\QTBUG-74291.XXXXXX.tmpFile)");
QTest::newRow("UNC-backslash")
<< "\\\\localhost\\" + tmpPath << "QTBUG-74291."
<< ".tmpFile"
<< "";
QTest::newRow("UNC-prefix")
<< "\\\\?\\UNC\\localhost\\" + tmpPath << "QTBUG-74291."
<< ".tmpFile"
<< "";
QTest::newRow("UNC-slash")
<< "//localhost/" + QDir::fromNativeSeparators(tmpPath) << "QTBUG-74291."
<< ".tmpFile"
<< "";
QTest::newRow("UNC-prefix-slash")
<< "//?/UNC/localhost/" + QDir::fromNativeSeparators(tmpPath) << "QTBUG-74291."
<< ".tmpFile"
<< "";
#endif
}