Utils: Add FilePath::symLinkTarget

And implement it for the docker device.

This replaces the previous unused and not really implemented
FilePath::resolveSymLinkTarget.

Change-Id: I9dcb4f8276dbb88b21959276da0d50135742fba0
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

src/libs/utils/fileutils.cpp

@@ -391,13 +391,6 @@ FilePath FilePath::resolvePath(const QString &fileName) const
     return FilePath::fromString(QDir::cleanPath(toString() + QLatin1Char('/') + fileName));
 }
 
-FilePath FilePath::resolveSymlinkTarget() const
-{
-    // FIXME: implement
-    QTC_CHECK(false);
-    return *this;
-}
-
 FilePath FilePath::cleanPath() const
 {
     FilePath result = *this;
@@ -1009,6 +1002,19 @@ bool FilePath::needsDevice() const
     return !m_scheme.isEmpty();
 }
 
+/// \returns an empty FilePath if this is not a symbolic linl
+FilePath FilePath::symLinkTarget() const
+{
+    if (needsDevice()) {
+        QTC_ASSERT(s_deviceHooks.symLinkTarget, return {});
+        return s_deviceHooks.symLinkTarget(*this);
+    }
+    const QFileInfo info(m_data);
+    if (!info.isSymLink())
+        return {};
+    return FilePath::fromString(info.symLinkTarget());
+}
+
 
 /// Find the parent directory of a given directory.
 

src/libs/utils/fileutils.h

@@ -83,6 +83,7 @@ public:
     std::function<bool(const FilePath &, const FilePath &)> copyFile;
     std::function<bool(const FilePath &, const FilePath &)> renameFile;
     std::function<FilePath(const FilePath &)> searchInPath;
+    std::function<FilePath(const FilePath &)> symLinkTarget;
     std::function<QList<FilePath>(const FilePath &, const QStringList &,
                                   QDir::Filters, QDir::SortFlags)> dirEntries;
     std::function<QByteArray(const FilePath &, int)> fileContents;
@@ -188,6 +189,7 @@ public:
     FilePath cleanPath() const;
 
     FilePath canonicalPath() const;
+    FilePath symLinkTarget() const;
 
     FilePath operator/(const QString &str) const;
 

src/plugins/docker/dockerdevice.cpp

@@ -1002,6 +1002,22 @@ QDateTime DockerDevice::lastModified(const FilePath &filePath) const
     return {};
 }
 
+FilePath DockerDevice::symLinkTarget(const FilePath &filePath) const
+{
+    QTC_ASSERT(handlesFile(filePath), return {});
+    tryCreateLocalFileAccess();
+    if (hasLocalFileAccess()) {
+        const FilePath localAccess = mapToLocalAccess(filePath);
+        const FilePath target = localAccess.symLinkTarget();
+        LOG("SymLinkTarget? " << filePath.toUserOutput() << localAccess.toUserOutput() << target);
+        if (target.isEmpty())
+            return {};
+        return mapToGlobalPath(target);
+    }
+    QTC_CHECK(false);
+    return {};
+}
+
 FilePath DockerDevice::searchInPath(const FilePath &filePath) const
 {
     const QString path = filePath.path();

src/plugins/docker/dockerdevice.h

@@ -89,6 +89,7 @@ public:
     bool copyFile(const Utils::FilePath &filePath, const Utils::FilePath &target) const override;
     bool renameFile(const Utils::FilePath &filePath, const Utils::FilePath &target) const override;
     Utils::FilePath searchInPath(const Utils::FilePath &filePath) const override;
+    Utils::FilePath symLinkTarget(const Utils::FilePath &filePath) const override;
     QList<Utils::FilePath> directoryEntries(const Utils::FilePath &filePath,
                                             const QStringList &nameFilters,
                                             QDir::Filters filters,

src/plugins/projectexplorer/devicesupport/devicemanager.cpp

@@ -459,6 +459,12 @@ DeviceManager::DeviceManager(bool isInstance) : d(std::make_unique<DeviceManager
         return device->searchInPath(filePath);
     };
 
+    deviceHooks.symLinkTarget = [](const FilePath &filePath) {
+        auto device = DeviceManager::deviceForPath(filePath);
+        QTC_ASSERT(device, return FilePath{});
+        return device->symLinkTarget(filePath);
+    };
+
     deviceHooks.dirEntries = [](const FilePath &filePath, const QStringList &nameFilters,
                                 QDir::Filters filters, QDir::SortFlags sort) {
         auto device = DeviceManager::deviceForPath(filePath);

src/plugins/projectexplorer/devicesupport/idevice.cpp

@@ -316,6 +316,13 @@ FilePath IDevice::searchInPath(const FilePath &filePath) const
     return Environment::systemEnvironment().searchInPath(filePath.path());
 }
 
+FilePath IDevice::symLinkTarget(const FilePath &filePath) const
+{
+    Q_UNUSED(filePath);
+    QTC_CHECK(false);
+    return {};
+}
+
 QList<FilePath> IDevice::directoryEntries(const FilePath &filePath,
                                           const QStringList &nameFilters,
                                           QDir::Filters filters,

src/plugins/projectexplorer/devicesupport/idevice.h

@@ -250,6 +250,7 @@ public:
     virtual bool copyFile(const Utils::FilePath &filePath, const Utils::FilePath &target) const;
     virtual bool renameFile(const Utils::FilePath &filePath, const Utils::FilePath &target) const;
     virtual Utils::FilePath searchInPath(const Utils::FilePath &filePath) const;
+    virtual Utils::FilePath symLinkTarget(const Utils::FilePath &filePath) const;
     virtual QList<Utils::FilePath> directoryEntries(const Utils::FilePath &filePath,
                                                     const QStringList &nameFilters,
                                                     QDir::Filters filters,