1 files changed, 341 insertions, 6 deletions
diff --git a/launcher/FileSystem.h b/launcher/FileSystem.h
index f083f3c7..cb581d0c 100644
--- a/launcher/FileSystem.h
+++ b/launcher/FileSystem.h
@@ -3,6 +3,7 @@
  *  Prism Launcher - Minecraft Launcher
  *  Copyright (C) 2022 Sefa Eyeoglu <contact@scrumplex.net>
  *  Copyright (C) 2022 TheKodeToad <TheKodeToad@proton.me>
+ *  Copyright (C) 2022 Rachel Powers <508861+Ryex@users.noreply.github.com>
  *
  *  This program is free software: you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -39,9 +40,13 @@
 #include "Exception.h"
 #include "pathmatcher/IPathMatcher.h"
 
+#include <system_error>
+
 #include <QDir>
 #include <QFlags>
+#include <QLocalServer>
 #include <QObject>
+#include <QThread>
 
 namespace FS {
 
@@ -77,7 +82,9 @@ bool ensureFilePathExists(QString filenamepath);
  */
 bool ensureFolderPathExists(QString filenamepath);
 
-/// @brief Copies a directory and it's contents from src to dest
+/**
+ * @brief Copies a directory and it's contents from src to dest
+ */
 class copy : public QObject {
     Q_OBJECT
    public:
@@ -122,13 +129,134 @@ class copy : public QObject {
     int m_copied;
 };
 
+struct LinkPair {
+    QString src;
+    QString dst;
+};
+
+struct LinkResult {
+    QString src;
+    QString dst;
+    QString err_msg;
+    int err_value;
+};
+
+class ExternalLinkFileProcess : public QThread {
+    Q_OBJECT
+   public:
+    ExternalLinkFileProcess(QString server, bool useHardLinks, QObject* parent = nullptr)
+        : QThread(parent), m_useHardLinks(useHardLinks), m_server(server)
+    {}
+
+    void run() override
+    {
+        runLinkFile();
+        emit processExited();
+    }
+
+   signals:
+    void processExited();
+
+   private:
+    void runLinkFile();
+
+    bool m_useHardLinks = false;
+
+    QString m_server;
+};
+
+/**
+ * @brief links (a file / a directory and it's contents) from src to dest
+ */
+class create_link : public QObject {
+    Q_OBJECT
+   public:
+    create_link(const QList<LinkPair> path_pairs, QObject* parent = nullptr) : QObject(parent) { m_path_pairs.append(path_pairs); }
+    create_link(const QString& src, const QString& dst, QObject* parent = nullptr) : QObject(parent)
+    {
+        LinkPair pair = { src, dst };
+        m_path_pairs.append(pair);
+    }
+    create_link& useHardLinks(const bool useHard)
+    {
+        m_useHardLinks = useHard;
+        return *this;
+    }
+    create_link& matcher(const IPathMatcher* filter)
+    {
+        m_matcher = filter;
+        return *this;
+    }
+    create_link& whitelist(bool whitelist)
+    {
+        m_whitelist = whitelist;
+        return *this;
+    }
+    create_link& linkRecursively(bool recursive)
+    {
+        m_recursive = recursive;
+        return *this;
+    }
+    create_link& setMaxDepth(int depth)
+    {
+        m_max_depth = depth;
+        return *this;
+    }
+    create_link& debug(bool d)
+    {
+        m_debug = d;
+        return *this;
+    }
+
+    std::error_code getOSError() { return m_os_err; }
+
+    bool operator()(bool dryRun = false) { return operator()(QString(), dryRun); }
+
+    int totalLinked() { return m_linked; }
+
+    void runPrivileged() { runPrivileged(QString()); }
+    void runPrivileged(const QString& offset);
+
+    QList<LinkResult> getResults() { return m_path_results; }
+
+   signals:
+    void fileLinked(const QString& srcName, const QString& dstName);
+    void linkFailed(const QString& srcName, const QString& dstName, const QString& err_msg, int err_value);
+    void finished();
+    void finishedPrivileged(bool gotResults);
+
+   private:
+    bool operator()(const QString& offset, bool dryRun = false);
+    void make_link_list(const QString& offset);
+    bool make_links();
+
+   private:
+    bool m_useHardLinks = false;
+    const IPathMatcher* m_matcher = nullptr;
+    bool m_whitelist = false;
+    bool m_recursive = true;
+
+    /// @brief >= -1 = infinite, 0 = link files at src/* to dest/*, 1 = link files at src/*/* to dest/*/*, etc.
+    int m_max_depth = -1;
+
+    QList<LinkPair> m_path_pairs;
+    QList<LinkResult> m_path_results;
+    QList<LinkPair> m_links_to_make;
+
+    int m_linked;
+    bool m_debug = false;
+    std::error_code m_os_err;
+
+    QLocalServer m_linkServer;
+};
+
 /**
  * @brief moves a file by renaming it
  * @param source source file path
  * @param dest destination filepath
- * 
+ *
  */
-bool move(const QString&  source, const QString& dest);
+bool move(const QString& source, const QString& dest);
 
 /**
  * Delete a folder recursively
@@ -138,13 +266,30 @@ bool deletePath(QString path);
 /**
  * Trash a folder / file
  */
-bool trash(QString path, QString *pathInTrash = nullptr);
+bool trash(QString path, QString* pathInTrash = nullptr);
 
 QString PathCombine(const QString& path1, const QString& path2);
 QString PathCombine(const QString& path1, const QString& path2, const QString& path3);
 QString PathCombine(const QString& path1, const QString& path2, const QString& path3, const QString& path4);
 
-QString AbsolutePath(QString path);
+QString AbsolutePath(const QString& path);
+
+/**
+ * @brief depth of path. "foo.txt" -> 0 , "bar/foo.txt" -> 1, /baz/bar/foo.txt -> 2, etc.
+ *
+ * @param path path to measure
+ * @return int number of components before base path
+ */
+int pathDepth(const QString& path);
+
+/**
+ * @brief  cut off segments of path until it is a max of length depth
+ *
+ * @param path path to truncate
+ * @param depth max depth of new path
+ * @return QString truncated path
+ */
+QString pathTruncate(const QString& path, int depth);
 
 /**
  * Resolve an executable
@@ -186,4 +331,194 @@ bool overrideFolder(QString overwritten_path, QString override_path);
  * Creates a shortcut to the specified target file at the specified destination path.
  */
 bool createShortcut(QString destination, QString target, QStringList args, QString name, QString icon);
-}
+
+enum class FilesystemType {
+    FAT,
+    NTFS,
+    REFS,
+    EXT,
+    EXT_2_OLD,
+    EXT_2_3_4,
+    XFS,
+    BTRFS,
+    NFS,
+    ZFS,
+    APFS,
+    HFS,
+    HFSPLUS,
+    HFSX,
+    FUSEBLK,
+    F2FS,
+    UNKNOWN
+};
+
+/**
+ * @brief Ordered Mapping of enum types to reported filesystem names
+ * this mapping is non exsaustive, it just attempts to capture the filesystems which could be reasonalbly be in use .
+ * all string values are in uppercase, use `QString.toUpper()` or equivalent during lookup.
+ *
+ * QMap is ordered
+ *
+ */
+static const QMap<FilesystemType, QStringList> s_filesystem_type_names = {
+    {FilesystemType::FAT,        { "FAT" }},
+    {FilesystemType::NTFS,       { "NTFS" }},
+    {FilesystemType::REFS,       { "REFS" }},
+    {FilesystemType::EXT_2_OLD,  { "EXT_2_OLD", "EXT2_OLD" }},
+    {FilesystemType::EXT_2_3_4,  { "EXT2/3/4", "EXT_2_3_4", "EXT2", "EXT3", "EXT4" }},
+    {FilesystemType::EXT,        { "EXT" }},
+    {FilesystemType::XFS,        { "XFS" }},
+    {FilesystemType::BTRFS,      { "BTRFS" }},
+    {FilesystemType::NFS,        { "NFS" }},
+    {FilesystemType::ZFS,        { "ZFS" }},
+    {FilesystemType::APFS,       { "APFS" }},
+    {FilesystemType::HFS,        { "HFS" }},
+    {FilesystemType::HFSPLUS,    { "HFSPLUS" }},
+    {FilesystemType::HFSX,       { "HFSX" }},
+    {FilesystemType::FUSEBLK,    { "FUSEBLK" }},
+    {FilesystemType::F2FS,       { "F2FS" }},
+    {FilesystemType::UNKNOWN,    { "UNKNOWN" }}
+};
+
+/**
+ * @brief Get the string name of Filesystem enum object
+ *
+ * @param type
+ * @return QString
+ */
+QString getFilesystemTypeName(FilesystemType type);
+
+/**
+ * @brief Get the Filesystem enum object from a name
+ *  Does a lookup of the type name and returns an exact match
+ *
+ * @param name
+ * @return FilesystemType
+ */
+FilesystemType getFilesystemType(const QString& name);
+
+/**
+ * @brief Get the Filesystem enum object from a name
+ *  Does a fuzzy lookup of the type name and returns an apropreate match
+ *
+ * @param name
+ * @return FilesystemType
+ */
+FilesystemType getFilesystemTypeFuzzy(const QString& name);
+
+struct FilesystemInfo {
+    FilesystemType fsType = FilesystemType::UNKNOWN;
+    QString fsTypeName;
+    int blockSize;
+    qint64 bytesAvailable;
+    qint64 bytesFree;
+    qint64 bytesTotal;
+    QString name;
+    QString rootPath;
+};
+
+/**
+ * @brief path to the near ancestor that exists
+ *
+ */
+QString nearestExistentAncestor(const QString& path);
+
+/**
+ * @brief colect information about the filesystem under a file
+ *
+ */
+FilesystemInfo statFS(const QString& path);
+
+static const QList<FilesystemType> s_clone_filesystems = { FilesystemType::BTRFS, FilesystemType::APFS, FilesystemType::ZFS,
+                                                           FilesystemType::XFS, FilesystemType::REFS };
+
+/**
+ * @brief if the Filesystem is reflink/clone capable
+ *
+ */
+bool canCloneOnFS(const QString& path);
+bool canCloneOnFS(const FilesystemInfo& info);
+bool canCloneOnFS(FilesystemType type);
+
+/**
+ * @brief if the Filesystems are reflink/clone capable and both are on the same device
+ *
+ */
+bool canClone(const QString& src, const QString& dst);
+
+/**
+ * @brief Copies a directory and it's contents from src to dest
+ */
+class clone : public QObject {
+    Q_OBJECT
+   public:
+    clone(const QString& src, const QString& dst, QObject* parent = nullptr) : QObject(parent)
+    {
+        m_src.setPath(src);
+        m_dst.setPath(dst);
+    }
+    clone& matcher(const IPathMatcher* filter)
+    {
+        m_matcher = filter;
+        return *this;
+    }
+    clone& whitelist(bool whitelist)
+    {
+        m_whitelist = whitelist;
+        return *this;
+    }
+
+    bool operator()(bool dryRun = false) { return operator()(QString(), dryRun); }
+
+    int totalCloned() { return m_cloned; }
+
+   signals:
+    void fileCloned(const QString& src, const QString& dst);
+    void cloneFailed(const QString& src, const QString& dst);
+
+   private:
+    bool operator()(const QString& offset, bool dryRun = false);
+
+   private:
+    const IPathMatcher* m_matcher = nullptr;
+    bool m_whitelist = false;
+    QDir m_src;
+    QDir m_dst;
+    int m_cloned;
+};
+
+/**
+ * @brief clone/reflink file from src to dst
+ *
+ */
+bool clone_file(const QString& src, const QString& dst, std::error_code& ec);
+
+#if defined(Q_OS_WIN)
+bool win_ioctl_clone(const std::wstring& src_path, const std::wstring& dst_path, std::error_code& ec);
+#elif defined(Q_OS_LINUX)
+bool linux_ficlone(const std::string& src_path, const std::string& dst_path, std::error_code& ec);
+#elif defined(Q_OS_MACOS) || defined(Q_OS_FREEBSD) || defined(Q_OS_OPENBSD)
+bool macos_bsd_clonefile(const std::string& src_path, const std::string& dst_path, std::error_code& ec);
+#endif
+
+static const QList<FilesystemType> s_non_link_filesystems = {
+    FilesystemType::FAT,
+};
+
+/**
+ * @brief if the Filesystem is symlink capable
+ *
+ */
+bool canLinkOnFS(const QString& path);
+bool canLinkOnFS(const FilesystemInfo& info);
+bool canLinkOnFS(FilesystemType type);
+
+/**
+ * @brief if the Filesystem is symlink capable on both ends
+ *
+ */
+bool canLink(const QString& src, const QString& dst);
+
+uintmax_t hardLinkCount(const QString& path);
+
+}  // namespace FS