freetype2/include/freetype/ftlogging.h

166 lines
3.9 KiB
C

/****************************************************************************
*
* ftlogging.h
*
* Additional debugging APIs.
*
* Copyright (C) 2020-2021 by
* David Turner, Robert Wilhelm, and Werner Lemberg.
*
* This file is part of the FreeType project, and may only be used,
* modified, and distributed under the terms of the FreeType project
* license, LICENSE.TXT. By continuing to use, modify, or distribute
* this file you indicate that you have read the license and
* understand and accept it fully.
*
*/
#ifndef FTLOGGING_H_
#define FTLOGGING_H_
#include <ft2build.h>
#include FT_CONFIG_CONFIG_H
FT_BEGIN_HEADER
/**************************************************************************
*
* @section:
* debugging_apis
*
* @title:
* External Debugging APIs
*
* @abstract:
* Public APIs to control the `FT_DEBUG_LOGGING` macro.
*
* @description:
* This section contains the declarations of public functions that
* enables fine control of what the `FT_DEBUG_LOGGING` macro outputs.
*
*/
/**************************************************************************
*
* @function:
* FT_Trace_Set_Level
*
* @description:
* Change the levels of tracing components of FreeType at run time.
*
* @input:
* tracing_level ::
* New tracing value.
*
* @example:
* The following call makes FreeType trace everything but the 'memory'
* component.
*
* ```
* FT_Trace_Set_Level( "any:7 memory:0 );
* ```
*
* @note:
* This function does nothing if compilation option `FT_DEBUG_LOGGING`
* isn't set.
*/
FT_EXPORT( void )
FT_Trace_Set_Level( const char* tracing_level );
/**************************************************************************
*
* @function:
* FT_Trace_Set_Default_Level
*
* @description:
* Reset tracing value of FreeType's components to the default value
* (i.e., to the value of the `FT2_DEBUG` environment value or to NULL
* if `FT2_DEBUG` is not set).
*
*
* @note:
* This function does nothing if compilation option `FT_DEBUG_LOGGING`
* isn't set.
*/
FT_EXPORT( void )
FT_Trace_Set_Default_Level( void );
/**************************************************************************
*
* @functype:
* FT_Custom_Log_Handler
*
* @description:
* A function typedef that is used to handle the logging of tracing and
* debug messages on a file system.
*
* @input:
* ft_component ::
* The name of `FT_COMPONENT` from which the current debug or error
* message is produced.
*
* fmt ::
* Actual debug or tracing message.
*
* args::
* Arguments of debug or tracing messages.
*/
typedef void
(*FT_Custom_Log_Handler)( const char* ft_component,
const char* fmt,
va_list args );
/**************************************************************************
*
* @function:
* FT_Set_Log_Handler
*
* @description:
* A function to set a custom log handler.
*
* @input:
* handler ::
* New logging function.
*
* @note:
* This function does nothing if compilation option `FT_DEBUG_LOGGING`
* isn't set.
*/
FT_EXPORT( void )
FT_Set_Log_Handler( FT_Custom_Log_Handler handler );
/**************************************************************************
*
* @function:
* FT_Set_Default_Log_Handler
*
* @description:
* A function to undo the effect of @FT_Set_Log_Handler, resetting the
* log handler to FreeType's built-in version.
*
* @note:
* This function does nothing if compilation option `FT_DEBUG_LOGGING`
* isn't set.
*/
FT_EXPORT( void )
FT_Set_Default_Log_Handler( void );
/* */
FT_END_HEADER
#endif /* FTLOGGING_H_ */
/* END */