Skip to navigation
API referenceModule APIClasses

hololink::module::LoggingInterfaceV1

View as Markdown

Application-wide sink for log messages.

The host application implements this interface (see logging_impl.cpp) and publishes it to loaded modules; this way all the loaded modules send their logging messages to the same application receiver.

Code within this framework normally logs through the HSB_LOG_TRACE, HSB_LOG_DEBUG, HSB_LOG_INFO, HSB_LOG_WARN and HSB_LOG_ERROR macros, which compare against level() before formatting the message and then call log() with the call site’s file, line and function.

#include <hololink/module/logging.hpp>

Inherits from: hololink::module::Service< LoggingInterfaceV1 > (public)

Methods

level

virtual LogLevel hololink::module::LoggingInterfaceV1::level() const

Returns the current setting for log level filtering.

A message should be sent to log() only if its level is greater than or equal to this value. Callers check this before building the message so that disabled log statements cost no formatting work. log() does not itself discard messages below this threshold.

Returns: The current threshold.

log

virtual void hololink::module::LoggingInterfaceV1::log(
    LogLevel level,
    const char *file,
    unsigned line,
    const char *function,
    const char *message
)

Deliver one fully formatted log message to the sink.

The sink decorates the message with its own metadata (for example severity, timestamp and thread) and writes it to its destination. This may be called concurrently from multiple threads. All pointer arguments must be non-null, NUL-terminated strings, and are only valid for the duration of the call.

Parameters

level
LogLevel

Severity of the message.

file
const char *

Source file of the call site.

line
unsigned

Line number of the call site.

function
const char *

Name of the function containing the call site.

message
const char *

The text to log; no further formatting is applied.

module

std::shared_ptr<Module> hololink::module::ServiceBase::module() const

The Module that this service was published from.

The service holds no strong reference to its Module, so this does not extend the Module’s lifetime.

Returns: The owning Module, or an empty pointer if the service has not been published or its Module no longer exists.

Static methods

get_service

static std::shared_ptr<LoggingInterfaceV1> hololink::module::LoggingInterfaceV1::get_service(
    std::shared_ptr<Module> module,
    bool allow_null = false
)

Fetch the process-wide logger from a module.

There is only one logger, so no instance identifier is needed.

Returns: A shared pointer to the logger.

Parameters

module
std::shared_ptr<Module>

The module to query.

allow_null
boolDefaults to false

If false (the default), throws std::runtime_error when the module doesn’t provide a logger (or module is null). If true, returns nullptr instead.

for_each_type_id

static bool hololink::module::Service<LoggingInterfaceV1>::for_each_type_id(
    Callback &&cb
)

Iterate over every type_id supported by this instance.

The callback signature is bool(const char*) — returning false halts the walk; true continues. Iteration is depth-first, so you’ll see the most specific implementation types first.