ifw::fnd Namespace Reference

This source file contains definitions of the types and constants to handle data types. More...

Namespaces
namespace	datatype
	This source file contains definitions of the types and constants to handle data types.
namespace	defs
namespace	fits
	This source file contains definitions of the types and constants to handle FITS.
namespace	test
namespace	tools
	Header file for the IFW Foundation Tools library.

Classes
class	Logger
	Abstract logger; downstream supplies an implementation. More...
class	ScopedTracer
	RAII tracer used by FNDTRACE. More...

Enumerations
enum class	LogLevel : int {   TRACE = 0 , DEBUG = 10 , INFO = 20 , WARNING = 30 ,   ERROR = 40 , OFF = 100 }
	Log severity, lowest to highest. More...

Functions
void	InstallLogger (std::unique_ptr< Logger > logger) noexcept
	Install the process-wide logger.
Logger &	Log ()
	Access the installed logger.
bool	HasLogger () noexcept
	true iff a logger has been installed.
std::unique_ptr< Logger >	MakeStdoutLogger ()
	Factory: a logger that prints to stdout.
std::unique_ptr< Logger >	MakeNullLogger ()
	Factory: a logger that discards everything.
std::string_view	LogLevelName (LogLevel level) noexcept
	Render a LogLevel as a short uppercase string.
std::string	IsoTimeNow (const int8_t precision)
std::string	ThreadName ()
	Return name of current thread.
double	TimeSecs ()
void	SleepSecs (const float sleep_time_in_seconds)
std::string	IsoTime (const double time_since_epoch, const uint8_t precision)
template<typename... Ts>
std::string	VariantToString (const std::variant< Ts... > &var)
std::string	TraceExtra ()
	Helper used by FNDTRACE.
template<typename... Args>
std::string	TraceExtra (fmt::string_view fmt_str, Args &&... args)

Detailed Description

This source file contains definitions of the types and constants to handle data types.

Inline function generating a location identifier: "<file>:<line>:<function>:<thread>".

Copyright

SPDX-FileCopyrightText: 2025-2026 European Southern Observatory (ESO) SPDX-License-Identifier: LGPL-3.0-only

Enumeration Type Documentation

LogLevel

enum class ifw::fnd::LogLevel : int

strong

Log severity, lowest to highest.

Numeric values are chosen to make (level >= threshold) the natural filter test. The OFF sentinel sits above ERROR so that setting the threshold to OFF disables all output.

Enumerator
TRACE
DEBUG
INFO
WARNING
ERROR
OFF

Function Documentation

HasLogger()

bool ifw::fnd::HasLogger ( )

noexcept

true iff a logger has been installed.

Provided so that low-level code (signal handlers, destructors running during shutdown) can avoid raising on a missing logger.

InstallLogger()

void ifw::fnd::InstallLogger ( std::unique_ptr< Logger > logger )

noexcept

Install the process-wide logger.

Must be called once, early in main(), before any ifw-fnd API call that may log. Ownership is transferred to ifw-fnd. Calling twice replaces the previous logger and destroys it.

IsoTime()

std::string ifw::fnd::IsoTime ( const double time_since_epoch, const uint8_t precision )

inline

Return the ISO8601 time based on the time since epoch, expressed in seconds/double.

Parameters

[in]	time_since_epoch	Time in seconds/double since epoch.
[in]	precision	Number of decimal places for the fractional part of the second.

Returns

ISO8601 time as a string with the requested precision.

Note

Intentionally NOT instrumented with FNDTRACE: this function is invoked from FNDLOC (via IsoTimeNow), so tracing it would cause infinite recursion when FND* macros are enabled at TRACE level.

IsoTimeNow()

std::string ifw::fnd::IsoTimeNow ( const int8_t precision )

inline

Return the ISO8601 time now.

Parameters

[in]

precision

Number of decimal places for the fractional part of the second.

Returns

ISO8601 time as a string with the requested precision.

Note

Intentionally NOT instrumented with FNDTRACE: FNDLOC expands to this call, so tracing it would cause infinite recursion when FND* macros are enabled at TRACE level.

Log()

Logger & ifw::fnd::Log

(

)

Access the installed logger.

Exceptions

std::runtime_error

if no logger has been installed.

LogLevelName()

std::string_view ifw::fnd::LogLevelName ( LogLevel level )

noexcept

Render a LogLevel as a short uppercase string.

Returns "TRACE" / "DEBUG" / "INFO" / "WARNING" / "ERROR" / "OFF". Used by MakeStdoutLogger() and available for downstream implementations.

MakeNullLogger()

std::unique_ptr< Logger > ifw::fnd::MakeNullLogger

(

)

Factory: a logger that discards everything.

Useful for unit tests that want ifw-fnd to be silent without having to redirect stdout.

MakeStdoutLogger()

std::unique_ptr< Logger > ifw::fnd::MakeStdoutLogger

(

)

Factory: a logger that prints to stdout.

Format: "<level> <message>\n". Intended for standalone tools and unit tests, not for production deployments.

SleepSecs()

void ifw::fnd::SleepSecs ( const float sleep_time_in_seconds )

inline

Sleep for the given period of time specified in seconds/double.

Parameters

[in]

sleep_time_in_seconds

Time in seconds to sleep.

Returns

Void.

ThreadName()

std::string ifw::fnd::ThreadName ( )

inline

Return name of current thread.

TimeSecs()

double ifw::fnd::TimeSecs ( )

inline

Return the current time since epoch in seconds/double.

Returns

Time in seconds since epoch as a double value.

Note

Intentionally NOT instrumented with FNDTRACE: this function is part of the FNDLOC expansion (via IsoTimeNow), and tracing it would cause infinite recursion when FND* macros are enabled at TRACE level.

TraceExtra() [1/2]

std::string ifw::fnd::TraceExtra ( )

inline

Helper used by FNDTRACE.

FNDTRACE() with no extra args returns "". With a format string (and optional args) returns the formatted result. Variadic templates handle the "first arg is format string" split that the C++ preprocessor can't do cleanly.

TraceExtra() [2/2]

template<typename... Args>

std::string ifw::fnd::TraceExtra ( fmt::string_view fmt_str, Args &&... args )

inline

VariantToString()

template<typename... Ts>

std::string ifw::fnd::VariantToString

(

const std::variant< Ts... > &

var

)