WebRTC Logging Initialization

Overview

This document explains how to initialize the WebRTC logging system, when it must be done, and the consequences of late initialization.

How to Initialize

To initialize logging with custom settings, call webrtc::InitializeLogging and pass a webrtc::LoggingConfig object.

Initialization can happen only once.

Example:

#include "rtc_base/logging.h"

int main() {
  webrtc::LoggingConfig config;
  config.set_min_severity(webrtc::LS_INFO);
  config.set_log_thread(true);
  config.set_log_timestamp(true);

  // Add custom sinks if needed
  // config.AddSink(std::make_unique<MyLogSink>());

  if (!webrtc::InitializeLogging(std::move(config))) {
    // Handle initialization failure (e.g., called too late)
  }

  // Proceed with WebRTC usage
}

When Initialization Must Be Done

Initialization must be performed before any other WebRTC API calls and before any logging occurs via RTC_LOG macros.

Implicit Initialization

If not initialized explicitly, logging initialization will happen implicitly upon the first logging call (e.g., RTC_LOG) or any function that accesses the logging configuration. The defaults used for implicit initialization are defined in the LoggingConfig struct.

Behavior When It Is Too Late

If InitializeLogging is called after the logging system has already been initialized (implicitly or explicitly):

1. The function will return false.
2. The provided LoggingConfig will be ignored.
3. The logging system will continue to operate with the configuration established by the first initialization.

To avoid this, ensure InitializeLogging is called as early as possible in the application's startup sequence.