Xenia-Canary/src/xenia/vfs/entry.h

/**
 ******************************************************************************
 * Xenia : Xbox 360 Emulator Research Project                                 *
 ******************************************************************************
 * Copyright 2020 Ben Vanik. All rights reserved.                             *
 * Released under the BSD license - see LICENSE in the root for more details. *
 ******************************************************************************
 */

#ifndef XENIA_VFS_ENTRY_H_
#define XENIA_VFS_ENTRY_H_

#include <memory>
#include <string>
#include <vector>

#include "xenia/base/filesystem.h"
#include "xenia/base/filesystem_wildcard.h"
#include "xenia/base/mapped_memory.h"
#include "xenia/base/mutex.h"
#include "xenia/base/string_buffer.h"
#include "xenia/xbox.h"

namespace xe {
namespace kernel {
class KernelState;
class XFile;
}  // namespace kernel
}  // namespace xe

namespace xe {
namespace vfs {

class Device;
class File;

// Matches https://source.winehq.org/source/include/winternl.h#1591.
enum class FileAction {
  kSuperseded = 0,
  kOpened = 1,
  kCreated = 2,
  kOverwritten = 3,
  kExists = 4,
  kDoesNotExist = 5,
};

enum class FileDisposition {
  // If exist replace, else create.
  kSuperscede = 0,
  // If exist open, else error.
  kOpen = 1,
  // If exist error, else create.
  kCreate = 2,
  // If exist open, else create.
  kOpenIf = 3,
  // If exist open and overwrite, else error.
  kOverwrite = 4,
  // If exist open and overwrite, else create.
  kOverwriteIf = 5,
};

// Reuse xe::filesystem definition.
using FileAccess = xe::filesystem::FileAccess;

enum FileAttributeFlags : uint32_t {
  kFileAttributeNone = 0x0000,
  kFileAttributeReadOnly = 0x0001,
  kFileAttributeHidden = 0x0002,
  kFileAttributeSystem = 0x0004,
  kFileAttributeDirectory = 0x0010,
  kFileAttributeArchive = 0x0020,
  kFileAttributeDevice = 0x0040,
  kFileAttributeNormal = 0x0080,
  kFileAttributeTemporary = 0x0100,
  kFileAttributeCompressed = 0x0800,
  kFileAttributeEncrypted = 0x4000,
};

class Entry {
 public:
  virtual ~Entry();

  void Dump(xe::StringBuffer* string_buffer, int indent);

  Device* device() const { return device_; }
  Entry* parent() const { return parent_; }
  const std::string& path() const { return path_; }
  const std::string& absolute_path() const { return absolute_path_; }
  const std::string& name() const { return name_; }
  uint32_t attributes() const { return attributes_; }
  size_t size() const { return size_; }
  size_t allocation_size() const { return allocation_size_; }
  uint64_t create_timestamp() const { return create_timestamp_; }
  uint64_t access_timestamp() const { return access_timestamp_; }
  uint64_t write_timestamp() const { return write_timestamp_; }

  bool is_read_only() const;

  Entry* GetChild(const std::string_view name);
  Entry* ResolvePath(const std::string_view path);

  const std::vector<std::unique_ptr<Entry>>& children() const {
    return children_;
  }
  size_t child_count() const { return children_.size(); }
  Entry* IterateChildren(const xe::filesystem::WildcardEngine& engine,
                         size_t* current_index);

  Entry* CreateEntry(const std::string_view name, uint32_t attributes);
  bool Delete(Entry* entry);
  bool Delete();
  void Touch();

  // If successful, out_file points to a new file. When finished, call
  // file->Destroy()
  virtual X_STATUS Open(uint32_t desired_access, File** out_file) = 0;

  virtual bool can_map() const { return false; }
  virtual std::unique_ptr<MappedMemory> OpenMapped(MappedMemory::Mode mode,
                                                   size_t offset = 0,
                                                   size_t length = 0) {
    return nullptr;
  }
  virtual void update() { return; }

 protected:
  Entry(Device* device, Entry* parent, const std::string_view path);

  virtual std::unique_ptr<Entry> CreateEntryInternal(
      const std::string_view name, uint32_t attributes) {
    return nullptr;
  }
  virtual bool DeleteEntryInternal(Entry* entry) { return false; }

  xe::global_critical_region global_critical_region_;
  Device* device_;
  Entry* parent_;
  std::string path_;
  std::string absolute_path_;
  std::string name_;
  uint32_t attributes_;  // FileAttributeFlags
  size_t size_;
  size_t allocation_size_;
  uint64_t create_timestamp_;
  uint64_t access_timestamp_;
  uint64_t write_timestamp_;
  std::vector<std::unique_ptr<Entry>> children_;
};

}  // namespace vfs
}  // namespace xe

#endif  // XENIA_VFS_ENTRY_H_