log Directory Reference

Directories
	include
	src

Detailed Description

`log` — Logging

Type-tagged logging built on spdlog. Singleton Logger with per-type logger registration, console + file output, async mode, and rotation. Integrates with the assert system via a weak-symbol handler when linked.

Public API

Type	Purpose
Logger	Singleton (Logger::Instance()). Registers backends, routes log calls.
Config	Output configuration: console/file patterns, rotation, async settings.
Level	kTrace, kDebug, kInfo, kWarn, kError, kCritical.
DefaultLogger	Built-in logger type (kName = "HELIOS").
kDefaultLogger	Constexpr instance of DefaultLogger.
LoggerTrait	Concept: empty struct with static constexpr std::string_view kName.
LoggerWithConfigTrait	Extends LoggerTrait with static constexpr Config kConfig.

Free Functions

Convenience wrappers around Logger::Instance():

helios::log::Trace("...");
helios::log::Debug("...");
helios::log::Info("...");
helios::log::Warn("...");
helios::log::Error("...");
helios::log::Critical("...");

All accept std::format_string overloads and typed-logger variants: Info(MyLogger{}, "msg").

Trace and Debug are compiled out in release builds (HELIOS_RELEASE_MODE).

Quick Start

#include <helios/log/logger.hpp>
 
helios::log::Info("Engine starting");
helios::log::Warn("Low memory: {} MB free", free_mb);
helios::log::Error("Failed to load '{}'", path);

No explicit initialization required — the default logger is created on first use with Config::Debug() (debug) or Config::Release() (release).

Custom Logger Types

struct RenderLogger {
  static constexpr std::string_view kName = "Render";
  static constexpr auto kConfig = helios::log::Config::ConsoleOnly();
};
 
helios::log::Logger::Instance().AddLogger(RenderLogger{});
helios::log::Info(RenderLogger{}, "Pipeline initialized");

Configuration

#include <helios/log/config.hpp>
 
auto config = helios::log::Config{
    .log_directory = "logs",
    .file_name_pattern = "{name}_{timestamp}.log",
    .enable_console = true,
    .enable_file = true,
    .async_logging = false,
    .max_file_size = 10 * 1024 * 1024,
    .max_files = 5,
};
 
// Presets
helios::log::Config::Default();
helios::log::Config::ConsoleOnly();
helios::log::Config::FileOnly();
helios::log::Config::Debug();
helios::log::Config::Release();

Runtime Control

auto& logger = helios::log::Logger::Instance();
 
logger.SetLevel(helios::log::Level::kWarn);
logger.SetLevel(RenderLogger{}, helios::log::Level::kDebug);
logger.FlushAll();
logger.RemoveLogger(RenderLogger{});

Assert Integration

When the log module is linked, assertion failures route through the log plugin handler (priority: custom handler → log plugin → stderr). On MSVC the handler is registered at initialization; on GCC/Clang it uses a weak symbol.

helios::SetAssertionHandler(
    [](std::string_view condition, const std::source_location& loc,
       std::string_view message) noexcept {
      helios::log::Critical("Assert: {} | {} [{}:{}]", condition, message,
                            loc.file_name(), loc.line());
    });

Dependencies

• container — MultiTypeMap for logger registry
• core — asserts
• utils — TypeIndex
• External: spdlog