1 files changed, 582 insertions, 0 deletions
diff --git a/src/common/fs/fs.h b/src/common/fs/fs.h
new file mode 100644
index 000000000..f6f256349
--- /dev/null
+++ b/src/common/fs/fs.h
@@ -0,0 +1,582 @@
+// Copyright 2021 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <filesystem>
+#include <memory>
+
+#include "common/fs/fs_types.h"
+#include "common/fs/fs_util.h"
+
+namespace Common::FS {
+
+class IOFile;
+
+// File Operations
+
+/**
+ * Creates a new file at path with the specified size.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - The input path's parent directory does not exist
+ * - Filesystem object at path exists
+ * - Filesystem at path is read only
+ *
+ * @param path Filesystem path
+ * @param size File size
+ *
+ * @returns True if the file creation succeeds, false otherwise.
+ */
+[[nodiscard]] bool NewFile(const std::filesystem::path& path, u64 size = 0);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool NewFile(const Path& path, u64 size = 0) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return NewFile(ToU8String(path), size);
+    } else {
+        return NewFile(std::filesystem::path{path}, size);
+    }
+}
+#endif
+
+/**
+ * Removes a file at path.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem object at path is not a file
+ * - Filesystem at path is read only
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if file removal succeeds or file does not exist, false otherwise.
+ */
+[[nodiscard]] bool RemoveFile(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool RemoveFile(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return RemoveFile(ToU8String(path));
+    } else {
+        return RemoveFile(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Renames a file from old_path to new_path.
+ *
+ * Failures occur when:
+ * - One or both input path(s) is not valid
+ * - Filesystem object at old_path does not exist
+ * - Filesystem object at old_path is not a file
+ * - Filesystem object at new_path exists
+ * - Filesystem at either path is read only
+ *
+ * @param old_path Old filesystem path
+ * @param new_path New filesystem path
+ *
+ * @returns True if file rename succeeds, false otherwise.
+ */
+[[nodiscard]] bool RenameFile(const std::filesystem::path& old_path,
+                              const std::filesystem::path& new_path);
+
+#ifdef _WIN32
+template <typename Path1, typename Path2>
+[[nodiscard]] bool RenameFile(const Path1& old_path, const Path2& new_path) {
+    using ValueType1 = typename Path1::value_type;
+    using ValueType2 = typename Path2::value_type;
+    if constexpr (IsChar<ValueType1> && IsChar<ValueType2>) {
+        return RenameFile(ToU8String(old_path), ToU8String(new_path));
+    } else if constexpr (IsChar<ValueType1> && !IsChar<ValueType2>) {
+        return RenameFile(ToU8String(old_path), new_path);
+    } else if constexpr (!IsChar<ValueType1> && IsChar<ValueType2>) {
+        return RenameFile(old_path, ToU8String(new_path));
+    } else {
+        return RenameFile(std::filesystem::path{old_path}, std::filesystem::path{new_path});
+    }
+}
+#endif
+
+/**
+ * Opens a file at path with the specified file access mode.
+ * This function behaves differently depending on the FileAccessMode.
+ * These behaviors are documented in each enum value of FileAccessMode.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem object at path is not a file
+ * - The file is not opened
+ *
+ * @param path Filesystem path
+ * @param mode File access mode
+ * @param type File type, default is BinaryFile. Use TextFile to open the file as a text file
+ * @param flag (Windows only) File-share access flag, default is ShareReadOnly
+ *
+ * @returns A shared pointer to the opened file. Returns nullptr on failure.
+ */
+[[nodiscard]] std::shared_ptr<IOFile> FileOpen(const std::filesystem::path& path,
+                                               FileAccessMode mode,
+                                               FileType type = FileType::BinaryFile,
+                                               FileShareFlag flag = FileShareFlag::ShareReadOnly);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] std::shared_ptr<IOFile> FileOpen(const Path& path, FileAccessMode mode,
+                                               FileType type = FileType::BinaryFile,
+                                               FileShareFlag flag = FileShareFlag::ShareReadOnly) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return FileOpen(ToU8String(path), mode, type, flag);
+    } else {
+        return FileOpen(std::filesystem::path{path}, mode, type, flag);
+    }
+}
+#endif
+
+// Directory Operations
+
+/**
+ * Creates a directory at path.
+ * Note that this function will *always* assume that the input path is a directory. For example,
+ * if the input path is /path/to/directory/file.txt, it will create a directory called "file.txt".
+ * If you intend to create the parent directory of a file, use CreateParentDir instead.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - The input path's parent directory does not exist
+ * - Filesystem at path is read only
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if directory creation succeeds or directory already exists, false otherwise.
+ */
+[[nodiscard]] bool CreateDir(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool CreateDir(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return CreateDir(ToU8String(path));
+    } else {
+        return CreateDir(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Recursively creates a directory at path.
+ * Note that this function will *always* assume that the input path is a directory. For example,
+ * if the input path is /path/to/directory/file.txt, it will create a directory called "file.txt".
+ * If you intend to create the parent directory of a file, use CreateParentDirs instead.
+ * Unlike CreateDir, this creates all of input path's parent directories if they do not exist.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem at path is read only
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if directory creation succeeds or directory already exists, false otherwise.
+ */
+[[nodiscard]] bool CreateDirs(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool CreateDirs(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return CreateDirs(ToU8String(path));
+    } else {
+        return CreateDirs(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Creates the parent directory of a given path.
+ * This function calls CreateDir(path.parent_path()), see CreateDir for more details.
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if directory creation succeeds or directory already exists, false otherwise.
+ */
+[[nodiscard]] bool CreateParentDir(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool CreateParentDir(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return CreateParentDir(ToU8String(path));
+    } else {
+        return CreateParentDir(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Recursively creates the parent directory of a given path.
+ * This function calls CreateDirs(path.parent_path()), see CreateDirs for more details.
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if directory creation succeeds or directory already exists, false otherwise.
+ */
+[[nodiscard]] bool CreateParentDirs(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool CreateParentDirs(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return CreateParentDirs(ToU8String(path));
+    } else {
+        return CreateParentDirs(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Removes a directory at path.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem object at path is not a directory
+ * - The given directory is not empty
+ * - Filesystem at path is read only
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if directory removal succeeds or directory does not exist, false otherwise.
+ */
+[[nodiscard]] bool RemoveDir(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool RemoveDir(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return RemoveDir(ToU8String(path));
+    } else {
+        return RemoveDir(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Removes all the contents within the given directory and removes the directory itself.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem object at path is not a directory
+ * - Filesystem at path is read only
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if the directory and all of its contents are removed successfully, false otherwise.
+ */
+[[nodiscard]] bool RemoveDirRecursively(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool RemoveDirRecursively(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return RemoveDirRecursively(ToU8String(path));
+    } else {
+        return RemoveDirRecursively(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Removes all the contents within the given directory without removing the directory itself.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem object at path is not a directory
+ * - Filesystem at path is read only
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if all of the directory's contents are removed successfully, false otherwise.
+ */
+[[nodiscard]] bool RemoveDirContentsRecursively(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool RemoveDirContentsRecursively(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return RemoveDirContentsRecursively(ToU8String(path));
+    } else {
+        return RemoveDirContentsRecursively(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Renames a directory from old_path to new_path.
+ *
+ * Failures occur when:
+ * - One or both input path(s) is not valid
+ * - Filesystem object at old_path does not exist
+ * - Filesystem object at old_path is not a directory
+ * - Filesystem object at new_path exists
+ * - Filesystem at either path is read only
+ *
+ * @param old_path Old filesystem path
+ * @param new_path New filesystem path
+ *
+ * @returns True if directory rename succeeds, false otherwise.
+ */
+[[nodiscard]] bool RenameDir(const std::filesystem::path& old_path,
+                             const std::filesystem::path& new_path);
+
+#ifdef _WIN32
+template <typename Path1, typename Path2>
+[[nodiscard]] bool RenameDir(const Path1& old_path, const Path2& new_path) {
+    using ValueType1 = typename Path1::value_type;
+    using ValueType2 = typename Path2::value_type;
+    if constexpr (IsChar<ValueType1> && IsChar<ValueType2>) {
+        return RenameDir(ToU8String(old_path), ToU8String(new_path));
+    } else if constexpr (IsChar<ValueType1> && !IsChar<ValueType2>) {
+        return RenameDir(ToU8String(old_path), new_path);
+    } else if constexpr (!IsChar<ValueType1> && IsChar<ValueType2>) {
+        return RenameDir(old_path, ToU8String(new_path));
+    } else {
+        return RenameDir(std::filesystem::path{old_path}, std::filesystem::path{new_path});
+    }
+}
+#endif
+
+/**
+ * Iterates over the directory entries of a given directory.
+ * This does not iterate over the sub-directories of the given directory.
+ * The DirEntryCallable callback is called for each visited directory entry.
+ * A filter can be set to control which directory entries are visited based on their type.
+ * By default, both files and directories are visited.
+ * If the callback returns false or there is an error, the iteration is immediately halted.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem object at path is not a directory
+ *
+ * @param path Filesystem path
+ * @param callback Callback to be called for each visited directory entry
+ * @param filter Directory entry type filter
+ */
+void IterateDirEntries(const std::filesystem::path& path, const DirEntryCallable& callback,
+                       DirEntryFilter filter = DirEntryFilter::All);
+
+#ifdef _WIN32
+template <typename Path>
+void IterateDirEntries(const Path& path, const DirEntryCallable& callback,
+                       DirEntryFilter filter = DirEntryFilter::All) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        IterateDirEntries(ToU8String(path), callback, filter);
+    } else {
+        IterateDirEntries(std::filesystem::path{path}, callback, filter);
+    }
+}
+#endif
+
+/**
+ * Iterates over the directory entries of a given directory and its sub-directories.
+ * The DirEntryCallable callback is called for each visited directory entry.
+ * A filter can be set to control which directory entries are visited based on their type.
+ * By default, both files and directories are visited.
+ * If the callback returns false or there is an error, the iteration is immediately halted.
+ *
+ * Failures occur when:
+ * - Input path is not valid
+ * - Filesystem object at path does not exist
+ * - Filesystem object at path is not a directory
+ *
+ * @param path Filesystem path
+ * @param callback Callback to be called for each visited directory entry
+ * @param filter Directory entry type filter
+ */
+void IterateDirEntriesRecursively(const std::filesystem::path& path,
+                                  const DirEntryCallable& callback,
+                                  DirEntryFilter filter = DirEntryFilter::All);
+
+#ifdef _WIN32
+template <typename Path>
+void IterateDirEntriesRecursively(const Path& path, const DirEntryCallable& callback,
+                                  DirEntryFilter filter = DirEntryFilter::All) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        IterateDirEntriesRecursively(ToU8String(path), callback, filter);
+    } else {
+        IterateDirEntriesRecursively(std::filesystem::path{path}, callback, filter);
+    }
+}
+#endif
+
+// Generic Filesystem Operations
+
+/**
+ * Returns whether a filesystem object at path exists.
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if a filesystem object at path exists, false otherwise.
+ */
+[[nodiscard]] bool Exists(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool Exists(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return Exists(ToU8String(path));
+    } else {
+        return Exists(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Returns whether a filesystem object at path is a file.
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if a filesystem object at path is a file, false otherwise.
+ */
+[[nodiscard]] bool IsFile(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool IsFile(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return IsFile(ToU8String(path));
+    } else {
+        return IsFile(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Returns whether a filesystem object at path is a directory.
+ *
+ * @param path Filesystem path
+ *
+ * @returns True if a filesystem object at path is a directory, false otherwise.
+ */
+[[nodiscard]] bool IsDir(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool IsDir(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return IsDir(ToU8String(path));
+    } else {
+        return IsDir(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Gets the current working directory.
+ *
+ * @returns The current working directory. Returns an empty path on failure.
+ */
+[[nodiscard]] std::filesystem::path GetCurrentDir();
+
+/**
+ * Sets the current working directory to path.
+ *
+ * @returns True if the current working directory is successfully set, false otherwise.
+ */
+[[nodiscard]] bool SetCurrentDir(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] bool SetCurrentDir(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return SetCurrentDir(ToU8String(path));
+    } else {
+        return SetCurrentDir(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Gets the entry type of the filesystem object at path.
+ *
+ * @param path Filesystem path
+ *
+ * @returns The entry type of the filesystem object. Returns file_type::not_found on failure.
+ */
+[[nodiscard]] std::filesystem::file_type GetEntryType(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] std::filesystem::file_type GetEntryType(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return GetEntryType(ToU8String(path));
+    } else {
+        return GetEntryType(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Gets the size of the filesystem object at path.
+ *
+ * @param path Filesystem path
+ *
+ * @returns The size in bytes of the filesystem object. Returns 0 on failure.
+ */
+[[nodiscard]] u64 GetSize(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] u64 GetSize(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return GetSize(ToU8String(path));
+    } else {
+        return GetSize(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Gets the free space size of the filesystem at path.
+ *
+ * @param path Filesystem path
+ *
+ * @returns The free space size in bytes of the filesystem at path. Returns 0 on failure.
+ */
+[[nodiscard]] u64 GetFreeSpaceSize(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] u64 GetFreeSpaceSize(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return GetFreeSpaceSize(ToU8String(path));
+    } else {
+        return GetFreeSpaceSize(std::filesystem::path{path});
+    }
+}
+#endif
+
+/**
+ * Gets the total capacity of the filesystem at path.
+ *
+ * @param path Filesystem path
+ *
+ * @returns The total capacity in bytes of the filesystem at path. Returns 0 on failure.
+ */
+[[nodiscard]] u64 GetTotalSpaceSize(const std::filesystem::path& path);
+
+#ifdef _WIN32
+template <typename Path>
+[[nodiscard]] u64 GetTotalSpaceSize(const Path& path) {
+    if constexpr (IsChar<typename Path::value_type>) {
+        return GetTotalSpaceSize(ToU8String(path));
+    } else {
+        return GetTotalSpaceSize(std::filesystem::path{path});
+    }
+}
+#endif
+
+} // namespace Common::FS