Miscellaneous utilities. More...

#include <util.hpp>

Classes
struct	OS
	OS dedicated utilities. More...

Static Public Member Functions
static int	osPriority (PidType pid)
	Retrieves the scheduling priority of a process. More...

static bool	osPriority (PidType pid, int prio)
	Sets the scheduling priority of a process. More...

static HandleType	guessHandle (HandleCategory category) noexcept
	Gets the type of the handle given a category. More...

static HandleType	guessHandle (FileHandle file) noexcept
	Gets the type of the stream to be used with the given descriptor. More...

static std::vector< CPUInfo >	cpuInfo () noexcept
	Gets information about the CPUs on the system. More...

static std::vector< InterfaceAddress >	interfaceAddresses () noexcept
	Gets a set of descriptors of all the available interfaces. More...

static std::string	indexToName (unsigned int index) noexcept
	IPv6-capable implementation of if_indextoname. More...

static std::string	indexToIid (unsigned int index) noexcept
	Retrieves a network interface identifier. More...

static bool	replaceAllocator (MallocFuncType mallocFunc, ReallocFuncType reallocFunc, CallocFuncType callocFunc, FreeFuncType freeFunc) noexcept
	Override the use of some standard library’s functions. More...

static std::array< double, 3 >	loadAverage () noexcept
	Gets the load average. More...

static char **	setupArgs (int argc, char **argv)
	Store the program arguments. More...

static std::string	processTitle ()
	Gets the title of the current process. More...

static bool	processTitle (std::string title)
	Sets the current process title. More...

static uint64_t	totalMemory () noexcept
	Gets memory information (in bytes). More...

static uint64_t	constrainedMemory () noexcept
	Gets the amount of memory available to the process (in bytes). More...

static double	uptime () noexcept
	Gets the current system uptime. More...

static RUsage	rusage () noexcept
	Gets the resource usage measures for the current process. More...

static uint64_t	hrtime () noexcept
	Gets the current high-resolution real time. More...

static std::string	path () noexcept
	Gets the executable path. More...

static std::string	cwd () noexcept
	Gets the current working directory. More...

static bool	chdir (const std::string &dir) noexcept
	Changes the current working directory. More...

static TimeVal64	timeOfDay ()
	Cross-platform implementation of `gettimeofday` More...

Detailed Description

Miscellaneous utilities.

Miscellaneous functions that don’t really belong to any other class.

Definition at line 473 of file util.hpp.

Member Function Documentation

◆ chdir()

static bool uvw::Utilities::chdir ( const std::string & dir )

inlinestaticnoexcept

Changes the current working directory.

Parameters

dir	The working directory to be set.

Returns: True in case of success, false otherwise.

Definition at line 965 of file util.hpp.

◆ constrainedMemory()

static uint64_t uvw::Utilities::constrainedMemory ( )

inlinestaticnoexcept

Gets the amount of memory available to the process (in bytes).

Gets the amount of memory available to the process based on limits imposed by the OS. If there is no such constraint, or the constraint is unknown, 0 is returned.
Note that it is not unusual for this value to be less than or greater than totalMemory.

Returns: Amount of memory available to the process.

Definition at line 902 of file util.hpp.

◆ cpuInfo()

static std::vector<CPUInfo> uvw::Utilities::cpuInfo ( )

inlinestaticnoexcept

Gets information about the CPUs on the system.

This function can be used to query the underlying system and get a set of descriptors of all the available CPUs.

Returns: A set of descriptors of all the available CPUs.

Definition at line 723 of file util.hpp.

◆ cwd()

static std::string uvw::Utilities::cwd ( )

inlinestaticnoexcept

Gets the current working directory.

Returns: The current working directory, an empty string in case of errors.

Definition at line 956 of file util.hpp.

◆ guessHandle() [1/2]

static HandleType uvw::Utilities::guessHandle ( HandleCategory category )

inlinestaticnoexcept

Gets the type of the handle given a category.

Parameters

category A properly initialized handle category.

Returns: The actual type of the handle as defined by HandleType

Definition at line 651 of file util.hpp.

◆ guessHandle() [2/2]

static HandleType uvw::Utilities::guessHandle ( FileHandle file )

inlinestaticnoexcept

Gets the type of the stream to be used with the given descriptor.

Returns the type of stream that should be used with a given file descriptor.
Usually this will be used during initialization to guess the type of the stdio streams.

Parameters

file	A valid descriptor.

Returns: One of the following types:

HandleType::UNKNOWN
HandleType::PIPE
HandleType::TCP
HandleType::TTY
HandleType::UDP
HandleType::FILE

Definition at line 710 of file util.hpp.

◆ hrtime()

static uint64_t uvw::Utilities::hrtime ( )

inlinestaticnoexcept

Gets the current high-resolution real time.

The time is expressed in nanoseconds. It is relative to an arbitrary time in the past. It is not related to the time of the day and therefore not subject to clock drift. The primary use is for measuring performance between interval.

Returns: The current high-resolution real time.

Definition at line 940 of file util.hpp.

◆ indexToIid()

static std::string uvw::Utilities::indexToIid ( unsigned int index )

inlinestaticnoexcept

Retrieves a network interface identifier.

See the official documentation for further details.

Parameters

index Network interface index.

Returns: Network interface identifier.

Definition at line 806 of file util.hpp.

◆ indexToName()

static std::string uvw::Utilities::indexToName ( unsigned int index )

inlinestaticnoexcept

IPv6-capable implementation of if_indextoname.

Mapping between network interface names and indexes.

See the official documentation for further details.

Parameters

index Network interface index.

Returns: Network interface name.

Definition at line 792 of file util.hpp.

◆ interfaceAddresses()

static std::vector<InterfaceAddress> uvw::Utilities::interfaceAddresses ( )

inlinestaticnoexcept

Gets a set of descriptors of all the available interfaces.

This function can be used to query the underlying system and get a set of descriptors of all the available interfaces, either internal or not.

Returns: A set of descriptors of all the available interfaces.

Definition at line 748 of file util.hpp.

◆ loadAverage()

static std::array<double, 3> uvw::Utilities::loadAverage ( )

inlinestaticnoexcept

Gets the load average.

Returns: [0,0,0] on Windows (not available), the load average otherwise.

Definition at line 841 of file util.hpp.

◆ osPriority() [1/2]

static int uvw::Utilities::osPriority ( PidType pid )

inlinestatic

Retrieves the scheduling priority of a process.

The returned value is between -20 (high priority) and 19 (low priority). A value that is out of range is returned in case of errors.

Note: On Windows, the result won't equal necessarily the exact value of the priority because of a mapping to a Windows priority class.

Parameters

pid	A valid process id.

Returns: The scheduling priority of the process.

Definition at line 617 of file util.hpp.

◆ osPriority() [2/2]

static bool uvw::Utilities::osPriority	(	PidType	pid,
		int	prio
	)

inlinestatic

Sets the scheduling priority of a process.

The returned value range is between -20 (high priority) and 19 (low priority).

Note: On Windows, the priority is mapped to a Windows priority class. When retrieving the process priority, the result won't equal necessarily the exact value of the priority.

Parameters

pid	A valid process id.
prio	The scheduling priority to set to the process.

Returns: True in case of success, false otherwise.

Definition at line 642 of file util.hpp.

◆ path()

static std::string uvw::Utilities::path ( )

inlinestaticnoexcept

Gets the executable path.

Returns: The executable path, an empty string in case of errors.

Definition at line 948 of file util.hpp.

◆ processTitle() [1/2]

static std::string uvw::Utilities::processTitle ( )

inlinestatic

Gets the title of the current process.

Returns: The process title.

Definition at line 862 of file util.hpp.

◆ processTitle() [2/2]

static bool uvw::Utilities::processTitle ( std::string title )

inlinestatic

Sets the current process title.

Parameters

title The process title to be set.

Returns: True in case of success, false otherwise.

Definition at line 879 of file util.hpp.

◆ replaceAllocator()

static bool uvw::Utilities::replaceAllocator	(	MallocFuncType	mallocFunc,
		ReallocFuncType	reallocFunc,
		CallocFuncType	callocFunc,
		FreeFuncType	freeFunc
	)

inlinestaticnoexcept

Override the use of some standard library’s functions.

Override the use of the standard library’s memory allocation functions.
This method must be invoked before any other uvw function is called or after all resources have been freed and thus the underlying library doesn’t reference any allocated memory chunk.

If any of the function pointers is null, the invokation will fail.

Note: There is no protection against changing the allocator multiple times. If the user changes it they are responsible for making sure the allocator is changed while no memory was allocated with the previous allocator, or that they are compatible.

Parameters

mallocFunc	Replacement function for malloc.
reallocFunc	Replacement function for realloc.
callocFunc	Replacement function for calloc.
freeFunc	Replacement function for free.

Returns: True in case of success, false otherwise.

Definition at line 833 of file util.hpp.

◆ rusage()

static RUsage uvw::Utilities::rusage ( )

inlinestaticnoexcept

Gets the resource usage measures for the current process.

Returns: Resource usage measures, zeroes-filled object in case of errors.

Definition at line 924 of file util.hpp.

◆ setupArgs()

static char** uvw::Utilities::setupArgs	(	int	argc,
		char **	argv
	)

inlinestatic

Store the program arguments.

Required for getting / setting the process title.

Returns: Arguments that haven't been consumed internally.

Definition at line 854 of file util.hpp.

◆ timeOfDay()

static TimeVal64 uvw::Utilities::timeOfDay ( )

inlinestatic

Cross-platform implementation of gettimeofday

Returns: The current time.

Definition at line 974 of file util.hpp.

◆ totalMemory()

static uint64_t uvw::Utilities::totalMemory ( )

inlinestaticnoexcept

Gets memory information (in bytes).

Returns: Memory information.

Definition at line 887 of file util.hpp.

◆ uptime()

static double uvw::Utilities::uptime ( )

inlinestaticnoexcept

Gets the current system uptime.

Returns: The current system uptime or 0 in case of errors.

Definition at line 910 of file util.hpp.

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

src/uvw/util.hpp

Classes

Static Public Member Functions

Detailed Description

Member Function Documentation

◆ chdir()

◆ constrainedMemory()

◆ cpuInfo()

◆ cwd()

◆ guessHandle() [1/2]

◆ guessHandle() [2/2]

◆ hrtime()

◆ indexToIid()

◆ indexToName()

◆ interfaceAddresses()

◆ loadAverage()

◆ osPriority() [1/2]

◆ osPriority() [2/2]

◆ path()

◆ processTitle() [1/2]

◆ processTitle() [2/2]

◆ replaceAllocator()

◆ rusage()

◆ setupArgs()

◆ timeOfDay()

◆ totalMemory()

◆ uptime()