fs Namespace Reference

Table of Contents

• Namespaces
• Classes
• Typedefs
• Enumerations
• Functions
• Detailed Description
• Typedef Documentation
• FileInfoWithDataConstPtr
• FileInfoWithDataMap
• Enumeration Type Documentation
• SettingsReadFile
• Function Documentation
• Chmod()
• CreateDirectories()
• FileExists()
• GetLexicallyRelative()
• ReadFileContents()
• ReadRecursiveFilesInfoWithData()
• RemoveSingleFile()
• Rename()
• RewriteFileContents()
• RewriteFileContentsAtomically()

filesystem support More...

Namespaces
namespace	blocking
	blocking function and classes to work with filesystem

Classes
struct	FileInfoWithData
	Struct file with load data. More...
class	FsCacheClient
	Class client for storing files in memory Usually retrieved from components::FsCache More...
class	TempFile
	A unique temporary file. The file is deleted when the TempFile object is destroyed. More...

Typedefs
using	FileInfoWithDataConstPtr = std::shared_ptr< const FileInfoWithData >
using	FileInfoWithDataMap = std::unordered_map< std::string, FileInfoWithDataConstPtr >

Enumerations
enum class	SettingsReadFile {   kNone = 0 ,   kSkipHidden = 1 << 0 }

Functions
std::string	GetLexicallyRelative (std::string_view path, std::string_view dir)
	Returns relative path from full path.
FileInfoWithDataMap	ReadRecursiveFilesInfoWithData (engine::TaskProcessor &async_tp, const std::string &path, utils::Flags< SettingsReadFile > flags={SettingsReadFile::kSkipHidden})
	Returns files from recursively traversed directory.
std::string	ReadFileContents (engine::TaskProcessor &async_tp, const std::string &path)
	Reads file contents asynchronously.
bool	FileExists (engine::TaskProcessor &async_tp, const std::string &path)
	Checks whether the file exists asynchronosly.
void	RewriteFileContents (engine::TaskProcessor &async_tp, const std::string &path, std::string_view contents)
	Rewrite file contents asynchronously It doesn't provide strict atomic guarantees. If you need them, use fs::RewriteFileContentsAtomically.
void	Rename (engine::TaskProcessor &async_tp, const std::string &source, const std::string &destination)
	Renames existing file.
void	RewriteFileContentsAtomically (engine::TaskProcessor &async_tp, const std::string &path, std::string_view contents, boost::filesystem::perms perms)
	Rewrite file contents atomically Write contents to temporary file in the same directory, then atomically replaces the destination file with the temporary file. Effectively does open()+write()+sync()+close()+rename()+sync(directory). It does both sync(2) for file and on the directory, so after successful return the file must persist on the filesystem.
void	Chmod (engine::TaskProcessor &async_tp, const std::string &path, boost::filesystem::perms perms)
	Change file mode.
bool	RemoveSingleFile (engine::TaskProcessor &async_tp, const std::string &path)
	Remove existing file.
void	CreateDirectories (engine::TaskProcessor &async_tp, std::string_view path, boost::filesystem::perms perms)
	Create directory and all necessary parent elements. Condition when path already exists and is a directory treated as "success" and no exception is thrown.
void	CreateDirectories (engine::TaskProcessor &async_tp, std::string_view path)

Detailed Description

filesystem support

Typedef Documentation

FileInfoWithDataConstPtr

using fs::FileInfoWithDataConstPtr = typedef std::shared_ptr<const FileInfoWithData>

Definition at line 24 of file read.hpp.

FileInfoWithDataMap

using fs::FileInfoWithDataMap = typedef std::unordered_map<std::string, FileInfoWithDataConstPtr>

Definition at line 25 of file read.hpp.

Enumeration Type Documentation

SettingsReadFile

enum class fs::SettingsReadFile

strong

Enumerator
kSkipHidden	Skip hidden files,.

Definition at line 28 of file read.hpp.

Function Documentation

Chmod()

void fs::Chmod	(	engine::TaskProcessor &	async_tp,
		const std::string &	path,
		boost::filesystem::perms	perms
	)

Change file mode.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	file path to chmod
perms	new file permissions

Exceptions

std::runtime_error

CreateDirectories()

void fs::CreateDirectories	(	engine::TaskProcessor &	async_tp,
		std::string_view	path,
		boost::filesystem::perms	perms
	)

Create directory and all necessary parent elements. Condition when path already exists and is a directory treated as "success" and no exception is thrown.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	directory to create

Exceptions

std::runtime_error

if there was an error while creating directories

FileExists()

bool fs::FileExists	(	engine::TaskProcessor &	async_tp,
		const std::string &	path
	)

Checks whether the file exists asynchronosly.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	file path to check

Returns

true if file exists, false if file doesn't exist

Exceptions

std::runtime_error

if something goes wrong (e.g. out of file descriptors)

GetLexicallyRelative()

std::string fs::GetLexicallyRelative	(	std::string_view	path,
		std::string_view	dir
	)

Returns relative path from full path.

Parameters

path	full path, must start with dir
dir	directory path to get relative path

Note

it does not access filesystem, the relative path is calculated lexically.

ReadFileContents()

std::string fs::ReadFileContents	(	engine::TaskProcessor &	async_tp,
		const std::string &	path
	)

Reads file contents asynchronously.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	file to open

Returns

file contents

Exceptions

std::runtime_error

if read fails for any reason (e.g. no such file, read error, etc.),

ReadRecursiveFilesInfoWithData()

FileInfoWithDataMap fs::ReadRecursiveFilesInfoWithData	(	engine::TaskProcessor &	async_tp,
		const std::string &	path,
		utils::Flags< SettingsReadFile >	flags = {SettingsReadFile::kSkipHidden}
	)

Returns files from recursively traversed directory.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	to directory to traverse recursively
flags	settings read files

Returns

map with relative to path filepaths and file info

Exceptions

std::runtime_error

if read fails for any reason (e.g. no such file, read error, etc.),

RemoveSingleFile()

bool fs::RemoveSingleFile	(	engine::TaskProcessor &	async_tp,
		const std::string &	path
	)

Remove existing file.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	file path to chmod

Returns

true if successfully removed, false if file doesn't exist

Exceptions

std::runtime_error

Rename()

void fs::Rename	(	engine::TaskProcessor &	async_tp,
		const std::string &	source,
		const std::string &	destination
	)

Renames existing file.

Parameters

async_tp	TaskProcessor for synchronous waiting
source	path to move from
destination	path to move to

Exceptions

std::runtime_error

RewriteFileContents()

void fs::RewriteFileContents	(	engine::TaskProcessor &	async_tp,
		const std::string &	path,
		std::string_view	contents
	)

Rewrite file contents asynchronously It doesn't provide strict atomic guarantees. If you need them, use fs::RewriteFileContentsAtomically.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	file to rewrite
contents	new file contents

Exceptions

std::runtime_error

if failed to overwrite

RewriteFileContentsAtomically()

void fs::RewriteFileContentsAtomically	(	engine::TaskProcessor &	async_tp,
		const std::string &	path,
		std::string_view	contents,
		boost::filesystem::perms	perms
	)

Rewrite file contents atomically Write contents to temporary file in the same directory, then atomically replaces the destination file with the temporary file. Effectively does open()+write()+sync()+close()+rename()+sync(directory). It does both sync(2) for file and on the directory, so after successful return the file must persist on the filesystem.

Parameters

async_tp	TaskProcessor for synchronous waiting
path	file path to rewrite
contents	new file contents
perms	new file permissions

Exceptions

std::runtime_error