Fix: define macros for logging levels

[babeltrace.git] / include / babeltrace2 / logging.h

#ifndef BABELTRACE2_LOGGING_H
#define BABELTRACE2_LOGGING_H

/*
 * Copyright (c) 2010-2019 EfficiOS Inc. and Linux Foundation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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#ifndef __BT_IN_BABELTRACE_H
# error "Please include <babeltrace2/babeltrace.h> instead."
#endif

#include <babeltrace2/logging-defs.h>

#ifdef __cplusplus
extern "C" {
#endif

/**
@defgroup logging Logging
@ingroup apiref
@brief Logging.

@code
#include <babeltrace2/logging.h>
@endcode

The functions in this module control the Babeltrace library's logging
behaviour.

You can set the current global log level of the library with
bt_logging_set_global_level(). Note that, if the level you set is below
the minimal logging level (configured at build time, which you can get
with bt_logging_get_minimal_level()), the logging statement between the
current global log level and the minimal log level are not executed.

@file
@brief Logging functions.
@sa logging

@addtogroup logging
@{
*/

/**
@brief Log levels.
*/
typedef enum bt_logging_level {
	/// Additional, low-level debugging context information.
	BT_LOGGING_LEVEL_TRACE		= __BT_LOGGING_LEVEL_TRACE,

	/**
	Debugging information, only useful when searching for the
	cause of a bug.
	*/
	BT_LOGGING_LEVEL_DEBUG		= __BT_LOGGING_LEVEL_DEBUG,

	/**
	Non-debugging information and failure to load optional
	subsystems.
	*/
	BT_LOGGING_LEVEL_INFO		= __BT_LOGGING_LEVEL_INFO,

	/**
	Errors caused by a bad usage of the library, that is, a
	non-observance of the documented function preconditions.

	The library's and object's states remain consistent when a
	warning is issued.
	*/
	BT_LOGGING_LEVEL_WARNING	= __BT_LOGGING_LEVEL_WARNING,

	/**
	An important error from which the library cannot recover, but
	the executed stack of functions can still return cleanly.
	*/
	BT_LOGGING_LEVEL_ERROR		= __BT_LOGGING_LEVEL_ERROR,

	/**
	The library cannot continue to work in this condition: it must
	terminate immediately, without even returning to the user's
	execution.
	*/
	BT_LOGGING_LEVEL_FATAL		= __BT_LOGGING_LEVEL_FATAL,

	/// Logging is disabled.
	BT_LOGGING_LEVEL_NONE		= __BT_LOGGING_LEVEL_NONE,
} bt_logging_level;

/**
@brief	Returns the minimal log level of the Babeltrace library.

The minimal log level is defined at the library's build time. Any
logging statement with a level below the minimal log level is not
compiled. This means that it is useless, although possible, to set the
global log level with bt_logging_set_global_level() below this level.

@returns	Minimal, build time log level.

@sa bt_logging_get_global_level(): Returns the current global log level.
*/
extern bt_logging_level bt_logging_get_minimal_level(void);

/**
@brief	Returns the current global log level of the Babeltrace library.

@returns	Current global log level.

@sa bt_logging_set_global_level(): Sets the current global log level.
@sa bt_logging_get_minimal_level(): Returns the minimal log level.
*/
extern bt_logging_level bt_logging_get_global_level(void);

/**
@brief	Sets the current global log level of the Babeltrace library
	to \p log_level.

If \p log_level is below what bt_logging_get_minimal_level() returns,
the logging statements with a level between \p log_level and the minimal
log level cannot be executed.

@param[in] log_level	Library's new global log level.

@sa bt_logging_get_global_level(): Returns the global log level.
*/
extern void bt_logging_set_global_level(bt_logging_level log_level);

/** @} */

#ifdef __cplusplus
}
#endif

#endif /* BABELTRACE2_LOGGING_H */