// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef STORAGE_BROWSER_FILE_SYSTEM_FILE_SYSTEM_FILE_UTIL_H_
#define STORAGE_BROWSER_FILE_SYSTEM_FILE_SYSTEM_FILE_UTIL_H_
#include <stdint.h>
#include <memory>
#include "base/component_export.h"
#include "base/files/file.h"
#include "base/files/file_path.h"
#include "storage/browser/blob/scoped_file.h"
#include "storage/browser/file_system/file_system_operation.h"
namespace base {
class Time;
}
namespace storage {
class FileSystemOperationContext;
class FileSystemURL;
// A file utility interface that provides basic file utility methods for
// FileSystem API.
//
// Layering structure of the FileSystemFileUtil was split out.
// See http://crbug.com/128136 if you need it.
class COMPONENT_EXPORT(STORAGE_BROWSER) FileSystemFileUtil {
public:
using CopyOrMoveOptionSet = FileSystemOperation::CopyOrMoveOptionSet;
// It will be implemented by each subclass such as FileSystemFileEnumerator.
class COMPONENT_EXPORT(STORAGE_BROWSER) AbstractFileEnumerator {
public:
virtual ~AbstractFileEnumerator() = default;
// The full path of the file. Returns an empty path if there are no more
// results.
virtual base::FilePath Next() = 0;
// Returns any file system error met during enumeration. It returns
// base::File::FILE_OK if enumeration stopped naturally (without error),
// even if the enumeration produced no results.
//
// Precondition: Next() was already called, at least once, and it most
// recently returned an empty path.
//
// TODO(b/329523214): in the long term, this should be a pure virtual
// method: "virtual base::File::Error GetError() = 0;".
virtual base::File::Error GetError();
// These methods return metadata for the file most recently returned by
// Next(). If Next() has never been called, or if Next() most recently
// returned an empty path, then they return the default values of "empty
// path", 0, "null time", and false, respectively.
// The display name of the file. For most platforms this will be
// Next().BaseName(), but for some files such as android content-URIs, the
// display name can be unrelated to the path.
virtual base::FilePath GetName() = 0;
virtual int64_t Size() = 0;
virtual base::Time LastModifiedTime() = 0;
virtual bool IsDirectory() = 0;
};
class COMPONENT_EXPORT(STORAGE_BROWSER) EmptyFileEnumerator
: public AbstractFileEnumerator {
base::FilePath Next() override;
base::File::Error GetError() override;
base::FilePath GetName() override;
int64_t Size() override;
base::Time LastModifiedTime() override;
bool IsDirectory() override;
};
FileSystemFileUtil(const FileSystemFileUtil&) = delete;
FileSystemFileUtil& operator=(const FileSystemFileUtil&) = delete;
virtual ~FileSystemFileUtil() = default;
// Creates or opens a file with the given flags.
// See header comments for AsyncFileUtil::CreateOrOpen() for more details.
// This is used only by Pepper/NaCl File API.
virtual base::File CreateOrOpen(FileSystemOperationContext* context,
const FileSystemURL& url,
int file_flags) = 0;
// Ensures that the given |url| exist. This creates a empty new file
// at |url| if the |url| does not exist.
// See header comments for AsyncFileUtil::EnsureFileExists() for more details.
virtual base::File::Error EnsureFileExists(
FileSystemOperationContext* context,
const FileSystemURL& url,
bool* created) = 0;
// Creates directory at given url.
// See header comments for AsyncFileUtil::CreateDirectory() for more details.
virtual base::File::Error CreateDirectory(FileSystemOperationContext* context,
const FileSystemURL& url,
bool exclusive,
bool recursive) = 0;
// Retrieves the information about a file.
// See header comments for AsyncFileUtil::GetFileInfo() for more details.
virtual base::File::Error GetFileInfo(FileSystemOperationContext* context,
const FileSystemURL& url,
base::File::Info* file_info,
base::FilePath* platform_path) = 0;
// Returns a pointer to a new instance of AbstractFileEnumerator which is
// implemented for each FileSystemFileUtil subclass. The instance needs to be
// freed by the caller, and its lifetime should not extend past when the
// current call returns to the main FILE message loop.
//
// The supplied context must remain valid at least lifetime of the enumerator
// instance. |this| must remain valid through the lifetime of the created
// enumerator instance.
virtual std::unique_ptr<AbstractFileEnumerator> CreateFileEnumerator(
FileSystemOperationContext* context,
const FileSystemURL& root_url,
bool recursive) = 0;
// Maps |file_system_url| given |context| into |local_file_path|
// which represents physical file location on the host OS.
// This may not always make sense for all subclasses.
virtual base::File::Error GetLocalFilePath(
FileSystemOperationContext* context,
const FileSystemURL& file_system_url,
base::FilePath* local_file_path) = 0;
// Updates the file metadata information.
// See header comments for AsyncFileUtil::Touch() for more details.
virtual base::File::Error Touch(FileSystemOperationContext* context,
const FileSystemURL& url,
const base::Time& last_access_time,
const base::Time& last_modified_time) = 0;
// Truncates a file to the given length.
// See header comments for AsyncFileUtil::Truncate() for more details.
virtual base::File::Error Truncate(FileSystemOperationContext* context,
const FileSystemURL& url,
int64_t length) = 0;
// Copies a single file or moves a single file or directory from |src_url| to
// |dest_url|. Whether moving a directory is supported is
// implementation-defined. The filesystem type of |src_url| and |dest_url|
// MUST be same. For |option|, please see file_system_operation.h
//
// This returns:
// - File::FILE_ERROR_NOT_FOUND if |src_url|
// or the parent directory of |dest_url| does not exist.
// - File::FILE_ERROR_NOT_A_FILE if |src_url| exists but is not a file and the
// operation is copy or the implementation does not support moving
// directories.
// - File::FILE_ERROR_INVALID_OPERATION if |dest_url| exists and
// is not a file.
// - File::FILE_ERROR_FAILED if |dest_url| does not exist and
// its parent path is a file.
//
virtual base::File::Error CopyOrMoveFile(FileSystemOperationContext* context,
const FileSystemURL& src_url,
const FileSystemURL& dest_url,
CopyOrMoveOptionSet options,
bool copy) = 0;
// Copies in a single file from a different filesystem.
// See header comments for AsyncFileUtil::CopyInForeignFile() for
// more details.
virtual base::File::Error CopyInForeignFile(
FileSystemOperationContext* context,
const base::FilePath& src_file_path,
const FileSystemURL& dest_url) = 0;
// Deletes a single file.
// See header comments for AsyncFileUtil::DeleteFile() for more details.
virtual base::File::Error DeleteFile(FileSystemOperationContext* context,
const FileSystemURL& url) = 0;
// Deletes a single empty directory.
// See header comments for AsyncFileUtil::DeleteDirectory() for more details.
virtual base::File::Error DeleteDirectory(FileSystemOperationContext* context,
const FileSystemURL& url) = 0;
// Creates a local snapshot file for a given |url| and returns the
// metadata and platform path of the snapshot file via |callback|.
//
// See header comments for AsyncFileUtil::CreateSnapshotFile() for
// more details.
virtual ScopedFile CreateSnapshotFile(FileSystemOperationContext* context,
const FileSystemURL& url,
base::File::Error* error,
base::File::Info* file_info,
base::FilePath* platform_path) = 0;
protected:
FileSystemFileUtil() = default;
};
} // namespace storage
#endif // STORAGE_BROWSER_FILE_SYSTEM_FILE_SYSTEM_FILE_UTIL_H_