Logger

Overview

Simple logging utility using plog.

The omdi::logger namespace provides a small wrapper around the plog logging library, with convenience functions for:

Messages are formatted using omdi::fmt::vformat() with a printf-style format string and a variable argument list.

Usage example

Basic initialization and logging:

// Initialize logging with default debug severity
omdi::logger::Init();

omdi::logger::Debug("Application started: version=%s", "1.0.0");
omdi::logger::Warning("Low memory: %d MB remaining", 128);
omdi::logger::Error("Failed to open file: %s", "data.txt");

// Generic logging with custom severity (template parameter)
omdi::logger::Log<plog::info>("User %s logged in", "alice");

// Fatal logs throw after logging
try {
  omdi::logger::Fatal("Unrecoverable error: code=%d", -1);
} catch (const std::runtime_error& e) {
  // Handle or report fatal error
}

Types

using Severity = plog::Severity

Alias for plog::Severity, used to represent log severity levels such as plog::debug, plog::info, plog::warning, plog::error, and plog::fatal.

Initialization

void Init(const Severity &minSeverity = plog::debug)

Initialize the logging system.

Parameters:

minSeverity – Minimum severity level for messages to be logged (defaults to plog::debug).

This function sets up plog sinks/appenders according to your application’s configuration (implementation-specific). It should typically be called once at application startup before any logging occurs.

Generic logging

template<Severity S = plog::debug>
void Log(const char *fmt, ...)

Log a formatted message at compile-time-selected severity S.

Template Parameters:

S – Compile-time severity level (defaults to plog::debug).

Parameters:

  • fmt – printf-style format string.

  • ... – Arguments corresponding to fmt.

Example:

omdi::logger::Log<plog::info>("Loaded %d items from %s", count, filename);

Internally, this formats the message with omdi::fmt::vformat() and sends it to plog via PLOG(S).

Severity-specific helpers

void Debug(const char *fmt, ...)

Log a debug-level message.

Parameters:

  • fmt – printf-style format string.

  • ... – Arguments corresponding to fmt.

Equivalent to calling omdi::logger::Log() with S = plog::debug.

void Warning(const char *fmt, ...)

Log a warning-level message.

Parameters:

  • fmt – printf-style format string.

  • ... – Arguments corresponding to fmt.

void Error(const char *fmt, ...)

Log an error-level message.

Parameters:

  • fmt – printf-style format string.

  • ... – Arguments corresponding to fmt.

[[noreturn]] void Fatal(const char *fmt, ...)

Log a fatal-level message and then throw an exception.

Parameters:

  • fmt – printf-style format string.

  • ... – Arguments corresponding to fmt.

This function:

  • formats the message using omdi::fmt::vformat(),

  • logs it with severity plog::fatal,

  • and then throws std::runtime_error containing the message.

Because it is marked [[noreturn]], it is intended for unrecoverable errors where normal execution cannot continue.

Notes

  • All logging functions use a printf-style interface. The number and types of arguments must match the format string.

  • The actual configuration of sinks (console, file, etc.) is determined by the implementation of omdi::logger::Init().

  • omdi::logger::Fatal() always throws after logging; callers should be prepared to handle std::runtime_error if they wish to catch it.