tor/src/trace/events.h

46 lines
1.4 KiB
C

/* Copyright (c) 2017, The Tor Project, Inc. */
/* See LICENSE for licensing information */
/**
* \file events.h
* \brief Header file for Tor event tracing.
**/
#ifndef TOR_TRACE_EVENTS_H
#define TOR_TRACE_EVENTS_H
/*
* The following defines a generic event tracing function name that has to be
* used to trace events in the code base.
*
* That generic function is then defined by a event tracing framework. For
* instance, the "log debug" framework sends all trace events to log_debug()
* which is defined in src/trace/debug.h which can only be enabled at compile
* time (--enable-event-tracing-debug).
*
* By default, every trace events in the code base are replaced by a NOP. See
* doc/HACKING/Tracing.md for more information on how to use event tracing or
* add events.
*/
#ifdef TOR_EVENT_TRACING_ENABLED
/* Map every trace event to a per subsystem macro. */
#define tor_trace(subsystem, name, ...) \
tor_trace_##subsystem(name, __VA_ARGS__)
/* Enable event tracing for the debug framework where all trace events are
* mapped to a log_debug(). */
#ifdef USE_EVENT_TRACING_DEBUG
#include "trace/debug.h"
#endif
#else /* TOR_EVENT_TRACING_ENABLED */
/* Reaching this point, we NOP every event declaration because event tracing
* is not been enabled at compile time. */
#define tor_trace(subsystem, name, args...)
#endif /* TOR_EVENT_TRACING_ENABLED */
#endif /* TOR_TRACE_EVENTS_H */