utils Namespace Reference

Classes
class	CArrayBuilder
class	CallbackGuard
	Callback guard. More...
class	CallbackWrapper
	Wraps callback and callback tracker into single object. More...
class	Channel
	Channel is implemented with a pair of anonymous sockets. More...
class	CountingMap
	Structure used to count elements. More...
class	EventFD
struct	UtilsException
	Base class for exceptions in utils. More...
struct	EventFDException
struct	ProvisionExistsException
class	ScopedGlibLoop
	Glib loop controller. More...
class	Glib
	Miscellaneous helpers for the Glib library. More...
class	Inotify
	Inotify monitors a directory and when a specified file or folder is created or deleted it calls a corresponding handler. More...
class	Latch
	A synchronization aid that allows one thread to wait until an operation being performed in other thread completes. More...
class	SameThreadGuard
	Same thread guard. More...
class	ScopedGError
class	SignalFD
	SignalFD takes control over handling signals sent to the thread. More...
class	ValueLatch
class	Worker
	A queue with tasks executed in a dedicated thread. More...

Typedefs
typedef CArrayBuilder< const char * >	CStringArrayBuilder
typedef std::function< void()>	VoidCallback

Enumerations
enum	Color : unsigned int {   Color::DEFAULT = 0, Color::BLACK = 30, Color::RED = 31, Color::GREEN = 32,   Color::YELLOW = 33, Color::BLUE = 34, Color::MAGENTA = 35, Color::CYAN = 36,   Color::WHITE = 37 }
enum	Attributes : unsigned int { Attributes::DEFAULT = 0, Attributes::BOLD = 1 }
enum	RunLevel : int { RUNLEVEL_POWEROFF = 0, RUNLEVEL_REBOOT = 6 }

Functions
template<class Callback >
CallbackWrapper< Callback > *	createCallbackWrapper (const Callback &callback, const CallbackGuard::Tracker &tracker)
	Creates callback wrapper. More...
template<class Callback >
void	deleteCallbackWrapper (void *pointer)
	Deletes callback wrapper. More...
template<class Callback >
const Callback &	getCallbackFromPointer (const void *pointer)
	Recovers callback from wrapper pointer. More...
std::string	getConsoleEscapeSequence (Attributes attr, Color color)
bool	daemonize ()
bool	setSuppGroups (const std::vector< std::string > &groups)
	Set supplementary groups to the current process. More...
bool	dropRoot (uid_t uid, gid_t gid, const std::vector< unsigned int > &caps)
	Set effective and permitted capabilities on the current process and drop root privileges. More...
bool	launchAsRoot (const std::function< bool()> &func)
	Launch func as root user. More...
bool	joinToNs (int nsPid, int ns)
	Join to namespace. More...
int	passNamespacedFd (int nsPid, int ns, const std::function< int()> &fdFactory)
	Pass file descriptor from namespace of some process. More...
std::string	getSystemErrorMessage ()
	Return string describing error number it is wrapper for strerror_r. More...
std::string	getSystemErrorMessage (int err)
bool	waitPid (pid_t pid, int &status)
	Wait until child processes ends. More...
int	open (const std::string &path, int flags, mode_t mode=-1)
	Open a file. More...
void	close (int fd)
	Close the file descriptor. More...
void	shutdown (int fd)
	Shut down part of a full-duplex connection. More...
int	ioctl (int fd, unsigned long request, void *argp)
	Operation on a special file. More...
int	dup2 (int olfFD, int newFD, bool closeOnExec=false)
	Duplicate one file desciptor onto another. More...
void	write (int fd, const void *bufferPtr, const size_t size, int timeoutMS=5000)
	Write to a file descriptor, throw on error. More...
void	read (int fd, void *bufferPtr, const size_t size, int timeoutMS=5000)
	Read from a file descriptor, throw on error. More...
unsigned int	getMaxFDNumber ()
void	setMaxFDNumber (unsigned int limit)
	Set the software and hardware limit of file descriptors for this process. More...
unsigned int	getFDNumber ()
int	fdRecv (int socket, const unsigned int timeoutMS=5000)
	Receive fd via Unix Domain socket. More...
bool	fdSend (int socket, int fd, const unsigned int timeoutMS=5000)
	Send Socket via Unix Domain socket. More...
void	setCloseOnExec (int fd, bool closeOnExec)
	Set or remove CLOEXEC on a file descriptor. More...
void	setNonBlocking (int fd, bool nonBlocking)
	Set or remove NONBLOCK on a file descriptor. More...
void	waitForFile (const std::string &file, const unsigned int timeoutMs)
std::string	readFileStream (const std::string &path)
	Reads the content of file stream (no seek); Throws exception on error. More...
bool	readFileStream (const std::string &path, std::string &result)
	Reads the content of file stream (no seek) More...
std::string	readFileContent (const std::string &path)
	Reads the content of a file (performs seek); Throws exception on error. More...
bool	readFileContent (const std::string &path, std::string &content)
	Reads the content of a file. More...
bool	saveFileContent (const std::string &path, const std::string &content)
	Save the content to the file. More...
bool	readFirstLineOfFile (const std::string &path, std::string &ret)
	Read a line from file Its goal is to read a kernel config files (eg. More...
bool	removeFile (const std::string &path)
	Remove file. More...
bool	isCharDevice (const std::string &path)
	Checks if a char device exists. More...
void	assertIsDir (const std::string &path)
	Checks if a path exists and points to a directory. More...
void	assertIsAbsolute (const std::string &path)
	Checks if path is absolute. More...
bool	mountRun (const std::string &path)
	Mounts run as a tmpfs on a given path. More...
bool	mount (const std::string &source, const std::string &target, const std::string &filesystemtype, unsigned long mountflags, const std::string &data)
	Creates mount point. More...
bool	umount (const std::string &path)
	Umounts a filesystem. More...
bool	isMountPoint (const std::string &path, bool &result)
	Check if given path is a mount point. More...
bool	hasSameMountPoint (const std::string &path1, const std::string &path2, bool &result)
	Checks whether the given paths are under the same mount point. More...
bool	moveFile (const std::string &src, const std::string &dst)
	Moves the file either by rename if under the same mount point or by copy&delete if under a different one. More...
bool	copyDirContents (const std::string &src, const std::string &dst)
	Recursively copy contents of src dir to dst dir. More...
bool	createDir (const std::string &path, uid_t uid, uid_t gid, boost::filesystem::perms mode)
	Creates a directory with specific UID, GID and permissions set. More...
bool	createDirs (const std::string &path, mode_t mode)
	Recursively creates a directory with specific permissions set. More...
bool	createEmptyDir (const std::string &path)
	Creates an empty directory, ready to serve as mount point. More...
bool	createFile (const std::string &path, int flags, mode_t mode)
	Creates an empty file. More...
bool	createFifo (const std::string &path, mode_t mode)
	Creates an FIFO special file. More...
bool	copyFile (const std::string &src, const std::string &dest)
	Copy an file. More...
bool	createLink (const std::string &src, const std::string &dest)
	Create hard link. More...
bool	listDir (const std::string &path, std::vector< std::string > &files)
	List all (including '. More...
void	executeInGlibThread (const VoidCallback &callback, const CallbackGuard &guard)
	Executes a callback in glib thread (adds an iddle event to glib) More...
bool	getFreeLoopDevice (std::string &ret)
	Returns string with first free loop device. More...
bool	mountImage (const std::string &image, const std::string &loopdev, const std::string &path)
	Mount an ext4 image from file on a given path by using a loop device. More...
bool	umountImage (const std::string &path, const std::string &loopdev)
	Umounts previously mounted image. More...
bool	copyImageContents (const std::string &img, const std::string &dst)
	Mounts an image and copies its contents to dst directory. More...
bool	setRunLevel (RunLevel runLevel)
template<class T >
void	make_clean (T &value)
template<class T >
T	make_clean ()
template<class... Paths>
std::string	createFilePath (const Paths &...paths)
std::string	dirName (std::string path)
std::string	getAbsolutePath (const std::string &path, const std::string &base)
std::ostream &	operator<< (std::ostream &os, const ScopedGError &e)
::sigset_t	getSignalMask ()
bool	isSignalPending (const int sigNum)
bool	waitForSignal (const int sigNum, int timeoutMs)
bool	isSignalBlocked (const int sigNum)
void	signalBlock (const int sigNum)
void	signalBlockAllExcept (const std::initializer_list< int > &signals)
void	signalUnblock (const int sigNum)
std::vector< std::pair< int, struct::sigaction > >	signalIgnore (const std::initializer_list< int > &signals)
struct::sigaction	signalSet (const int sigNum, const struct::sigaction *sigAct)
void	sendSignal (const pid_t pid, const int sigNum)
template<class Predicate >
bool	spinWaitFor (int timeoutMs, Predicate pred)
std::string	toHexString (const void *data, unsigned len)
	Convert binary bytes array to hex string representation. More...
std::vector< std::string >	split (const std::string &str, const std::string &delim)
bool	beginsWith (std::string const &value, std::string const &part)
bool	endsWith (std::string const &value, std::string const &part)
template<typename T >
std::string	join (const std::vector< T > &vec, const char *delim)
std::string	getTypeName (const std::type_info &ti)
template<class T >
std::string	getTypeName (const T &t)
bool	activateVT (const int &vt)
bool	executeAndWait (const std::function< void()> &func, int &status)
	Execute function in child process. More...
bool	executeAndWait (const std::function< void()> &func)
bool	executeAndWait (const char *fname, const char *const *argv, int &status)
bool	executeAndWait (const char *fname, const char *const *argv)
	Execute binary. More...

Variables
const int	ERROR_MESSAGE_BUFFER_CAPACITY = 256

Typedef Documentation

typedef CArrayBuilder<const char*> utils::CStringArrayBuilder

typedef std::function<void()> utils::VoidCallback

Enumeration Type Documentation

enum utils::Attributes : unsigned int

strong

Enumerator
DEFAULT
BOLD

enum utils::Color : unsigned int

strong

Enumerator
DEFAULT
BLACK
RED
GREEN
YELLOW
BLUE
MAGENTA
CYAN
WHITE

enum utils::RunLevel : int

Enumerator
RUNLEVEL_POWEROFF
RUNLEVEL_REBOOT

Function Documentation

bool utils::activateVT

(

const int &

vt

)

void utils::assertIsAbsolute

(

const std::string &

path

)

Checks if path is absolute.

void utils::assertIsDir

(

const std::string &

path

)

Checks if a path exists and points to a directory.

bool utils::beginsWith ( std::string const &  value, std::string const &  part  )

inline

void utils::close

(

int

fd

)

Close the file descriptor.

bool utils::copyDirContents	(	const std::string &	src,
		const std::string &	dst
	)

Recursively copy contents of src dir to dst dir.

bool utils::copyFile	(	const std::string &	src,
		const std::string &	dest
	)

Copy an file.

bool utils::copyImageContents	(	const std::string &	img,
		const std::string &	dst
	)

Mounts an image and copies its contents to dst directory.

template<class Callback >

CallbackWrapper<Callback>* utils::createCallbackWrapper	(	const Callback &	callback,
		const CallbackGuard::Tracker &	tracker
	)

Creates callback wrapper.

Useful for C callback api.

bool utils::createDir	(	const std::string &	path,
		uid_t	uid,
		uid_t	gid,
		boost::filesystem::perms	mode
	)

Creates a directory with specific UID, GID and permissions set.

bool utils::createDirs	(	const std::string &	path,
		mode_t	mode
	)

Recursively creates a directory with specific permissions set.

bool utils::createEmptyDir

(

const std::string &

path

)

Creates an empty directory, ready to serve as mount point.

Succeeds either if path did not exist and was created successfully, or if already existing dir under the same path is empty and is not a mount point.

bool utils::createFifo	(	const std::string &	path,
		mode_t	mode
	)

Creates an FIFO special file.

bool utils::createFile	(	const std::string &	path,
		int	flags,
		mode_t	mode
	)

Creates an empty file.

template<class... Paths>

std::string utils::createFilePath

(

const Paths &...

paths

)

bool utils::createLink	(	const std::string &	src,
		const std::string &	dest
	)

Create hard link.

bool utils::daemonize

(

)

Close all open standard file descriptors

template<class Callback >

void utils::deleteCallbackWrapper

(

void *

pointer

)

Deletes callback wrapper.

Useful for C callback api.

std::string utils::dirName ( std::string  path )

inline

bool utils::dropRoot	(	uid_t	uid,
		gid_t	gid,
		const std::vector< unsigned int > &	caps
	)

Set effective and permitted capabilities on the current process and drop root privileges.

int utils::dup2	(	int	oldFD,
		int	newFD,
		bool	closeOnExec
	)

Duplicate one file desciptor onto another.

bool utils::endsWith ( std::string const &  value, std::string const &  part  )

inline

bool utils::executeAndWait	(	const std::function< void()> &	func,
		int &	status
	)

Execute function in child process.

bool utils::executeAndWait

(

const std::function< void()> &

func

)

bool utils::executeAndWait	(	const char *	fname,
		const char *const *	argv,
		int &	status
	)

bool utils::executeAndWait	(	const char *	fname,
		const char *const *	argv
	)

Execute binary.

void utils::executeInGlibThread	(	const VoidCallback &	callback,
		const CallbackGuard &	guard
	)

Executes a callback in glib thread (adds an iddle event to glib)

int utils::fdRecv	(	int	socket,
		const unsigned int	timeoutMS
	)

Receive fd via Unix Domain socket.

bool utils::fdSend	(	int	socket,
		int	fd,
		const unsigned int	timeoutMS
	)

Send Socket via Unix Domain socket.

std::string utils::getAbsolutePath ( const std::string &  path, const std::string &  base  )

inline

template<class Callback >

const Callback& utils::getCallbackFromPointer

(

const void *

pointer

)

Recovers callback from wrapper pointer.

Useful for C callback api.

std::string utils::getConsoleEscapeSequence	(	Attributes	attr,
		Color	color
	)

unsigned int utils::getFDNumber

(

)

Returns

number of opened file descriptors by this process

bool utils::getFreeLoopDevice

(

std::string &

ret

)

Returns string with first free loop device.

unsigned int utils::getMaxFDNumber

(

)

Returns

the max number of file descriptors for this process.

sigset_t utils::getSignalMask

(

)

std::string utils::getSystemErrorMessage

(

)

Return string describing error number it is wrapper for strerror_r.

std::string utils::getSystemErrorMessage

(

int

err

)

std::string utils::getTypeName

(

const std::type_info &

ti

)

template<class T >

std::string utils::getTypeName

(

const T &

t

)

bool utils::hasSameMountPoint	(	const std::string &	path1,
		const std::string &	path2,
		bool &	result
	)

Checks whether the given paths are under the same mount point.

int utils::ioctl	(	int	fd,
		unsigned long	request,
		void *	argp
	)

Operation on a special file.

bool utils::isCharDevice

(

const std::string &

path

)

Checks if a char device exists.

bool utils::isMountPoint	(	const std::string &	path,
		bool &	result
	)

Check if given path is a mount point.

bool utils::isSignalBlocked

(

const int

sigNum

)

bool utils::isSignalPending

(

const int

sigNum

)

template<typename T >

std::string utils::join	(	const std::vector< T > &	vec,
		const char *	delim
	)

bool utils::joinToNs	(	int	nsPid,
		int	ns
	)

Join to namespace.

bool utils::launchAsRoot

(

const std::function< bool()> &

func

)

Launch func as root user.

This function forks, sets UID 0 to child process and calls func.

bool utils::listDir	(	const std::string &	path,
		std::vector< std::string > &	files
	)

List all (including '.

' and '..' entries) dir entries

template<class T >

void utils::make_clean

(

T &

value

)

template<class T >

T utils::make_clean

(

)

bool utils::mount	(	const std::string &	source,
		const std::string &	target,
		const std::string &	filesystemtype,
		unsigned long	mountflags,
		const std::string &	data
	)

Creates mount point.

bool utils::mountImage	(	const std::string &	image,
		const std::string &	path,
		const std::string &	loopdev
	)

Mount an ext4 image from file on a given path by using a loop device.

bool utils::mountRun

(

const std::string &

path

)

Mounts run as a tmpfs on a given path.

bool utils::moveFile	(	const std::string &	src,
		const std::string &	dst
	)

Moves the file either by rename if under the same mount point or by copy&delete if under a different one.

The destination has to be a full path including file name.

int utils::open	(	const std::string &	path,
		int	flags,
		mode_t	mode
	)

Open a file.

std::ostream& utils::operator<<	(	std::ostream &	os,
		const ScopedGError &	e
	)

Parameters

os	the output stream
e	error to write out

int utils::passNamespacedFd	(	int	nsPid,
		int	ns,
		const std::function< int()> &	fdFactory
	)

Pass file descriptor from namespace of some process.

void utils::read	(	int	fd,
		void *	bufferPtr,
		const size_t	size,
		int	timeoutMS = 5000
	)

Read from a file descriptor, throw on error.

Parameters

fd	file descriptor
bufferPtr	pointer to the data buffer
size	size of the data to read
timeoutMS	timeout in milliseconds

std::string utils::readFileContent

(

const std::string &

path

)

Reads the content of a file (performs seek); Throws exception on error.

bool utils::readFileContent	(	const std::string &	path,
		std::string &	result
	)

Reads the content of a file.

std::string utils::readFileStream

(

const std::string &

path

)

Reads the content of file stream (no seek); Throws exception on error.

bool utils::readFileStream	(	const std::string &	path,
		std::string &	result
	)

Reads the content of file stream (no seek)

bool utils::readFirstLineOfFile	(	const std::string &	path,
		std::string &	ret
	)

Read a line from file Its goal is to read a kernel config files (eg.

from /proc, /sys/)

bool utils::removeFile

(

const std::string &

path

)

Remove file.

bool utils::saveFileContent	(	const std::string &	path,
		const std::string &	content
	)

Save the content to the file.

void utils::sendSignal	(	const pid_t	pid,
		const int	sigNum
	)

void utils::setCloseOnExec	(	int	fd,
		bool	closeOnExec
	)

Set or remove CLOEXEC on a file descriptor.

void utils::setMaxFDNumber

(

unsigned int

limit

)

Set the software and hardware limit of file descriptors for this process.

Parameters

limit

limit of file descriptors

void utils::setNonBlocking	(	int	fd,
		bool	nonBlocking
	)

Set or remove NONBLOCK on a file descriptor.

bool utils::setRunLevel

(

RunLevel

runLevel

)

bool utils::setSuppGroups

(

const std::vector< std::string > &

groups

)

Set supplementary groups to the current process.

void utils::shutdown

(

int

fd

)

Shut down part of a full-duplex connection.

void utils::signalBlock

(

const int

sigNum

)

void utils::signalBlockAllExcept

(

const std::initializer_list< int > &

signals

)

std::vector< std::pair< int, struct::sigaction > > utils::signalIgnore

(

const std::initializer_list< int > &

signals

)

struct::sigaction utils::signalSet	(	const int	sigNum,
		const struct::sigaction *	sigAct
	)

void utils::signalUnblock

(

const int

sigNum

)

template<class Predicate >

bool utils::spinWaitFor	(	int	timeoutMs,
		Predicate	pred
	)

std::vector< std::string > utils::split	(	const std::string &	str,
		const std::string &	delim
	)

std::string utils::toHexString	(	const void *	data,
		unsigned	len
	)

Convert binary bytes array to hex string representation.

bool utils::umount

(

const std::string &

path

)

Umounts a filesystem.

bool utils::umountImage	(	const std::string &	path,
		const std::string &	loopdev
	)

Umounts previously mounted image.

This call will also free loop device used to mount specified path.

void utils::waitForFile	(	const std::string &	file,
		const unsigned int	timeoutMs
	)

bool utils::waitForSignal	(	const int	sigNum,
		int	timeoutMs
	)

bool utils::waitPid	(	pid_t	pid,
		int &	status
	)

Wait until child processes ends.

void utils::write	(	int	fd,
		const void *	bufferPtr,
		const size_t	size,
		int	timeoutMS = 5000
	)

Write to a file descriptor, throw on error.

Parameters

fd	file descriptor
bufferPtr	pointer to the data buffer
size	size of data to write
timeoutMS	timeout in milliseconds

Variable Documentation

const int utils::ERROR_MESSAGE_BUFFER_CAPACITY = 256