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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef DOM_FS_PARENT_DATAMODEL_FILESYSTEMFILEMANAGER_H_
#define DOM_FS_PARENT_DATAMODEL_FILESYSTEMFILEMANAGER_H_
#include "ErrorList.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/dom/FileSystemTypes.h"
#include "mozilla/dom/QMResult.h"
#include "nsIFile.h"
#include "nsString.h"
template <class T>
class nsCOMPtr;
class nsIFileURL;
namespace mozilla::dom {
namespace quota {
struct OriginMetadata;
} // namespace quota
namespace fs {
struct FileId;
namespace data {
/**
* @brief Get the directory for file system items of specified origin.
* Use this instead of constructing the path from quota manager's storage path.
*
* @param aOrigin Specified origin
* @return Result<nsCOMPtr<nsIFile>, QMResult> Top file system directory
*/
Result<nsCOMPtr<nsIFile>, QMResult> GetFileSystemDirectory(
const quota::OriginMetadata& aOriginMetadata);
/**
* @brief Ensure that the origin-specific directory for file system exists.
*
* @param aOriginMetadata Specified origin metadata
* @return nsresult Error if operation failed
*/
nsresult EnsureFileSystemDirectory(
const quota::OriginMetadata& aOriginMetadata);
/**
* @brief Get file system's database path for specified origin.
* Use this to get the database path instead of constructing it from
* quota manager's storage path - without the side effect of potentially
* creating it.
*
* @param aOrigin Specified origin
* @return Result<nsCOMPtr<nsIFile>, QMResult> Database file object
*/
Result<nsCOMPtr<nsIFile>, QMResult> GetDatabaseFile(
const quota::OriginMetadata& aOriginMetadata);
/**
* @brief Get file system's database url with directory lock parameter for
* specified origin. Use this to open a database connection and have the quota
* manager guard against its deletion or busy errors due to other connections.
*
* @param aOrigin Specified origin
* @param aDirectoryLockId Directory lock id from the quota manager
* @return Result<nsCOMPtr<nsIFileURL>, QMResult> Database file URL object
*/
Result<nsCOMPtr<nsIFileURL>, QMResult> GetDatabaseFileURL(
const quota::OriginMetadata& aOriginMetadata,
const int64_t aDirectoryLockId);
/**
* @brief Creates and removes disk-backed representations of the file systems'
* file entries for a specified origin.
*
* Other components should not depend on how the files are organized on disk
* but instead rely on the entry id and have access to the local file using the
* GetOrCreateFile result.
*
* The local paths are not necessarily stable in the long term and if they
* absolutely must be cached, there should be a way to repopulate the cache
* after an internal reorganization of the file entry represenations on disk,
* for some currently unforeseen maintenance reason.
*
* Example: if GetOrCreateFile used to map entryId 'abc' to path '/c/u/1/123'
* and now it maps it to '/d/u/1/12/123', the cache should either update all
* paths at once through a migration, or purge them and save a new value
* whenever a call to GetOrCreateFile is made.
*/
class FileSystemFileManager {
public:
/**
* @brief Create a File System File Manager object for a specified origin.
*
* @param aOrigin
* @return Result<FileSystemFileManager, QMResult>
*/
static Result<UniquePtr<FileSystemFileManager>, QMResult>
CreateFileSystemFileManager(const quota::OriginMetadata& aOriginMetadata);
/**
* @brief Create a File System File Manager object which keeps file entries
* under a specified directory instead of quota manager's storage path.
* This should only be used for testing and preferably removed.
*
* @param topDirectory
* @return Result<FileSystemFileManager, QMResult>
*/
static Result<FileSystemFileManager, QMResult> CreateFileSystemFileManager(
nsCOMPtr<nsIFile>&& topDirectory);
/**
* @brief Get a file object for a specified entry id. If a file for the entry
* does not exist, returns an appropriate error.
*
* @param aEntryId Specified id of a file system entry
* @return Result<nsCOMPtr<nsIFile>, QMResult> File or error.
*/
Result<nsCOMPtr<nsIFile>, QMResult> GetFile(const FileId& aFileId) const;
/**
* @brief Get or create a disk-backed file object for a specified entry id.
*
* @param aFileId Specified id of a file system entry
* @return Result<nsCOMPtr<nsIFile>, QMResult> File abstraction or IO error
*/
Result<nsCOMPtr<nsIFile>, QMResult> GetOrCreateFile(const FileId& aFileId);
/**
* @brief Create a disk-backed file object as a copy.
*
* @param aDestinationFileId Specified id of file to be created
* @param aSourceFileId Specified id of the file from which we make a copy
* @return Result<nsCOMPtr<nsIFile>, QMResult> File abstraction or IO error
*/
Result<nsCOMPtr<nsIFile>, QMResult> CreateFileFrom(
const FileId& aDestinationFileId, const FileId& aSourceFileId);
/**
* @brief Remove the disk-backed file object for a specified entry id.
* Note: The returned value is 0 in release builds.
*
* @param aFileId Specified id of a file system entry
* @return Result<Usage, QMResult> Error or file size
*/
Result<Usage, QMResult> RemoveFile(const FileId& aFileId);
/**
* @brief This method can be used to try to delete a group of files from the
* disk. In debug builds, the sum of the usages is provided ad return value,
* in release builds the sum is not calculated.
* The method attempts to remove all the files requested.
*/
Result<DebugOnly<Usage>, QMResult> RemoveFiles(
const nsTArray<FileId>& aFileIds, nsTArray<FileId>& aFailedRemovals);
private:
explicit FileSystemFileManager(nsCOMPtr<nsIFile>&& aTopDirectory);
nsCOMPtr<nsIFile> mTopDirectory;
};
} // namespace data
} // namespace fs
} // namespace mozilla::dom
#endif // DOM_FS_PARENT_DATAMODEL_FILESYSTEMFILEMANAGER_H_