seqan3::detail::safe_filesystem_entry Class Reference

A safe guard to manage a filesystem entry, e.g. a file or a directory. More...

#include <seqan3/io/detail/safe_filesystem_entry.hpp>

Public Member Functions
bool	remove ()
	Removes a file or empty directory.
std::uintmax_t	remove_all ()
	Removes a file or directory and all its contents, recursively.
bool	remove_no_throw () const noexcept
	Removes a file or empty directory.
Constructors, destructor and assignment
	safe_filesystem_entry ()=delete
	Deleted.
	safe_filesystem_entry (safe_filesystem_entry const &)=delete
	Deleted.
	safe_filesystem_entry (safe_filesystem_entry &&)=default
	Defaulted.
safe_filesystem_entry &	operator= (safe_filesystem_entry const &)=delete
	Deleted.
safe_filesystem_entry &	operator= (safe_filesystem_entry &&)=default
	Defaulted.
	safe_filesystem_entry (std::filesystem::path p)
	Constructs the safe guard from a std::filesystem::path.
	~safe_filesystem_entry ()
	Calls std::filesystem::remove_all on the wrapped entry.

Private Attributes
std::filesystem::path	entry
	The managed resource.

Detailed Description

A safe guard to manage a filesystem entry, e.g. a file or a directory.

This raii-wrapper class allows for a safe removal of a created filesystem entry such as a directory or file. This wrapper class assumes owning semantics. It is not copy-constructible or copy-assignable. In order to prevent misuse also the default constructor is deleted.

The following example demonstrates the use case.

// SPDX-FileCopyrightText: 2006-2024 Knut Reinert & Freie Universität Berlin
// SPDX-FileCopyrightText: 2016-2024 Knut Reinert & MPI für molekulare Genetik
// SPDX-License-Identifier: CC0-1.0
 
#include <filesystem>
#include <fstream>
 
#include <seqan3/io/detail/safe_filesystem_entry.hpp>
 
int main()
{
    std::filesystem::path my_file = std::filesystem::temp_directory_path() / "dummy.txt";
 
    std::ifstream file{my_file};                               // Create the file.
    seqan3::detail::safe_filesystem_entry file_guard{my_file}; // Safe cleanup in case of errors.
 
    // Do something on the file, that can possibly throw.
    // If an unhandled exception is thrown, the file guard destructor safely removes the file from the filesystem.
 
    file_guard.remove(); // Explicitly remove the file.
}

Constructor & Destructor Documentation

safe_filesystem_entry()

seqan3::detail::safe_filesystem_entry::safe_filesystem_entry ( std::filesystem::path  p )

inline

Constructs the safe guard from a std::filesystem::path.

Parameters

p	The path pointing to a filesystem entry.

Member Function Documentation

remove()

bool seqan3::detail::safe_filesystem_entry::remove ( )

inline

Removes a file or empty directory.

Returns

true if the file was deleted, false if it did not exist.

Exceptions

std::filesystem::filesystem_error

on underlying OS API errors.

Internally calls std::filesystem::remove on the stored std::filesystem::path.

remove_all()

std::uintmax_t seqan3::detail::safe_filesystem_entry::remove_all ( )

inline

Removes a file or directory and all its contents, recursively.

Returns

Returns the number of files and directories that were deleted (which may be zero if p did not exist to begin with).

Exceptions

std::filesystem::filesystem_error

on underlying OS API errors.

Internally calls std::filesystem::remove_all on the stored std::filesystem::path.

remove_no_throw()

bool seqan3::detail::safe_filesystem_entry::remove_no_throw ( ) const

inlinenoexcept

Removes a file or empty directory.

Returns

true if the file was deleted, false if it did not exist.

Exceptions

std::filesystem::filesystem_error

on underlying OS API errors.

Internally calls std::filesystem::remove on the stored std::filesystem::path.

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The documentation for this class was generated from the following file:

• safe_filesystem_entry.hpp