/**************************************************************************** * * ftdebug.h * * Debugging and logging component (specification). * * Copyright (C) 1996-2024 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. * * * IMPORTANT: A description of FreeType's debugging support can be * found in 'docs/DEBUG.TXT'. Read it if you need to use or * understand this code. * */ #ifndef FTDEBUG_H_ #define FTDEBUG_H_ #include #include FT_CONFIG_CONFIG_H #include #include "compiler-macros.h" #ifdef FT_DEBUG_LOGGING #define DLG_STATIC #include #include #include #endif /* FT_DEBUG_LOGGING */ FT_BEGIN_HEADER /* force the definition of FT_DEBUG_LEVEL_TRACE if FT_DEBUG_LOGGING is */ /* already defined. */ /* */ #ifdef FT_DEBUG_LOGGING #undef FT_DEBUG_LEVEL_TRACE #define FT_DEBUG_LEVEL_TRACE #endif /* force the definition of FT_DEBUG_LEVEL_ERROR if FT_DEBUG_LEVEL_TRACE */ /* is already defined; this simplifies the following #ifdefs */ /* */ #ifdef FT_DEBUG_LEVEL_TRACE #undef FT_DEBUG_LEVEL_ERROR #define FT_DEBUG_LEVEL_ERROR #endif /************************************************************************** * * Define the trace enums as well as the trace levels array when they are * needed. * */ #ifdef FT_DEBUG_LEVEL_TRACE #define FT_TRACE_DEF( x ) trace_ ## x , /* defining the enumeration */ typedef enum FT_Trace_ { #include trace_count } FT_Trace; /* a pointer to the array of trace levels, */ /* provided by `src/base/ftdebug.c' */ extern int* ft_trace_levels; #undef FT_TRACE_DEF #endif /* FT_DEBUG_LEVEL_TRACE */ /************************************************************************** * * Define the FT_TRACE macro * * IMPORTANT! * * Each component must define the macro FT_COMPONENT to a valid FT_Trace * value before using any TRACE macro. * * To get consistent logging output, there should be no newline character * (i.e., '\n') or a single trailing one in the message string of * `FT_TRACEx` and `FT_ERROR`. */ /************************************************************************* * * If FT_DEBUG_LOGGING is enabled, tracing messages are sent to dlg's API. * If FT_DEBUG_LOGGING is disabled, tracing messages are sent to * `FT_Message` (defined in ftdebug.c). */ #ifdef FT_DEBUG_LOGGING /* we need two macros to convert the names of `FT_COMPONENT` to a string */ #define FT_LOGGING_TAG( x ) FT_LOGGING_TAG_( x ) #define FT_LOGGING_TAG_( x ) #x /* we need two macros to convert the component and the trace level */ /* to a string that combines them */ #define FT_LOGGING_TAGX( x, y ) FT_LOGGING_TAGX_( x, y ) #define FT_LOGGING_TAGX_( x, y ) #x ":" #y #define FT_LOG( level, varformat ) \ do \ { \ const char* dlg_tag = FT_LOGGING_TAGX( FT_COMPONENT, level ); \ \ \ ft_add_tag( dlg_tag ); \ if ( ft_trace_levels[FT_TRACE_COMP( FT_COMPONENT )] >= level ) \ { \ if ( custom_output_handler != NULL ) \ FT_Logging_Callback varformat; \ else \ dlg_trace varformat; \ } \ ft_remove_tag( dlg_tag ); \ } while( 0 ) #else /* !FT_DEBUG_LOGGING */ #define FT_LOG( level, varformat ) \ do \ { \ if ( ft_trace_levels[FT_TRACE_COMP( FT_COMPONENT )] >= level ) \ FT_Message varformat; \ } while ( 0 ) #endif /* !FT_DEBUG_LOGGING */ #ifdef FT_DEBUG_LEVEL_TRACE /* we need two macros here to make cpp expand `FT_COMPONENT' */ #define FT_TRACE_COMP( x ) FT_TRACE_COMP_( x ) #define FT_TRACE_COMP_( x ) trace_ ## x #define FT_TRACE( level, varformat ) FT_LOG( level, varformat ) #else /* !FT_DEBUG_LEVEL_TRACE */ #define FT_TRACE( level, varformat ) do { } while ( 0 ) /* nothing */ #endif /* !FT_DEBUG_LEVEL_TRACE */ /************************************************************************** * * @function: * FT_Trace_Get_Count * * @description: * Return the number of available trace components. * * @return: * The number of trace components. 0 if FreeType 2 is not built with * FT_DEBUG_LEVEL_TRACE definition. * * @note: * This function may be useful if you want to access elements of the * internal trace levels array by an index. */ FT_BASE( FT_Int ) FT_Trace_Get_Count( void ); /************************************************************************** * * @function: * FT_Trace_Get_Name * * @description: * Return the name of a trace component. * * @input: * The index of the trace component. * * @return: * The name of the trace component. This is a statically allocated * C~string, so do not free it after use. `NULL` if FreeType is not * built with FT_DEBUG_LEVEL_TRACE definition. * * @note: * Use @FT_Trace_Get_Count to get the number of available trace * components. */ FT_BASE( const char* ) FT_Trace_Get_Name( FT_Int idx ); /************************************************************************** * * @function: * FT_Trace_Disable * * @description: * Switch off tracing temporarily. It can be activated again with * @FT_Trace_Enable. */ FT_BASE( void ) FT_Trace_Disable( void ); /************************************************************************** * * @function: * FT_Trace_Enable * * @description: * Activate tracing. Use it after tracing has been switched off with * @FT_Trace_Disable. */ FT_BASE( void ) FT_Trace_Enable( void ); /************************************************************************** * * You need two opening and closing parentheses! * * Example: FT_TRACE0(( "Value is %i", foo )) * * Output of the FT_TRACEX macros is sent to stderr. * */ #define FT_TRACE0( varformat ) FT_TRACE( 0, varformat ) #define FT_TRACE1( varformat ) FT_TRACE( 1, varformat ) #define FT_TRACE2( varformat ) FT_TRACE( 2, varformat ) #define FT_TRACE3( varformat ) FT_TRACE( 3, varformat ) #define FT_TRACE4( varformat ) FT_TRACE( 4, varformat ) #define FT_TRACE5( varformat ) FT_TRACE( 5, varformat ) #define FT_TRACE6( varformat ) FT_TRACE( 6, varformat ) #define FT_TRACE7( varformat ) FT_TRACE( 7, varformat ) /************************************************************************** * * Define the FT_ERROR macro. * * Output of this macro is sent to stderr. * */ #ifdef FT_DEBUG_LEVEL_ERROR /************************************************************************** * * If FT_DEBUG_LOGGING is enabled, error messages are sent to dlg's API. * If FT_DEBUG_LOGGING is disabled, error messages are sent to `FT_Message` * (defined in ftdebug.c). * */ #ifdef FT_DEBUG_LOGGING #define FT_ERROR( varformat ) \ do \ { \ const char* dlg_tag = FT_LOGGING_TAG( FT_COMPONENT ); \ \ \ ft_add_tag( dlg_tag ); \ dlg_trace varformat; \ ft_remove_tag( dlg_tag ); \ } while ( 0 ) #else /* !FT_DEBUG_LOGGING */ #define FT_ERROR( varformat ) FT_Message varformat #endif /* !FT_DEBUG_LOGGING */ #else /* !FT_DEBUG_LEVEL_ERROR */ #define FT_ERROR( varformat ) do { } while ( 0 ) /* nothing */ #endif /* !FT_DEBUG_LEVEL_ERROR */ /************************************************************************** * * Define the FT_ASSERT and FT_THROW macros. The call to `FT_Throw` makes * it possible to easily set a breakpoint at this function. * */ #ifdef FT_DEBUG_LEVEL_ERROR #define FT_ASSERT( condition ) \ do \ { \ if ( !( condition ) ) \ FT_Panic( "assertion failed on line %d of file %s\n", \ __LINE__, __FILE__ ); \ } while ( 0 ) #define FT_THROW( e ) \ ( FT_Throw( FT_ERR_CAT( FT_ERR_PREFIX, e ), \ __LINE__, \ __FILE__ ) | \ FT_ERR_CAT( FT_ERR_PREFIX, e ) ) #else /* !FT_DEBUG_LEVEL_ERROR */ #define FT_ASSERT( condition ) do { } while ( 0 ) #define FT_THROW( e ) FT_ERR_CAT( FT_ERR_PREFIX, e ) #endif /* !FT_DEBUG_LEVEL_ERROR */ /************************************************************************** * * Define `FT_Message` and `FT_Panic` when needed. * */ #ifdef FT_DEBUG_LEVEL_ERROR #include "stdio.h" /* for vfprintf() */ /* print a message */ FT_BASE( void ) FT_Message( const char* fmt, ... ); /* print a message and exit */ FT_BASE( void ) FT_Panic( const char* fmt, ... ); /* report file name and line number of an error */ FT_BASE( int ) FT_Throw( FT_Error error, int line, const char* file ); #endif /* FT_DEBUG_LEVEL_ERROR */ FT_BASE( void ) ft_debug_init( void ); #ifdef FT_DEBUG_LOGGING /************************************************************************** * * 'dlg' uses output handlers to control how and where log messages are * printed. Therefore we need to define a default output handler for * FreeType. */ FT_BASE( void ) ft_log_handler( const struct dlg_origin* origin, const char* string, void* data ); /************************************************************************** * * 1. `ft_default_log_handler` stores the function pointer that is used * internally by FreeType to print logs to a file. * * 2. `custom_output_handler` stores the function pointer to the callback * function provided by the user. * * It is defined in `ftdebug.c`. */ extern dlg_handler ft_default_log_handler; extern FT_Custom_Log_Handler custom_output_handler; /************************************************************************** * * If FT_DEBUG_LOGGING macro is enabled, FreeType needs to initialize and * un-initialize `FILE*`. * * These functions are defined in `ftdebug.c`. */ FT_BASE( void ) ft_logging_init( void ); FT_BASE( void ) ft_logging_deinit( void ); /************************************************************************** * * For printing the name of `FT_COMPONENT` along with the actual log we * need to add a tag with the name of `FT_COMPONENT`. * * These functions are defined in `ftdebug.c`. */ FT_BASE( void ) ft_add_tag( const char* tag ); FT_BASE( void ) ft_remove_tag( const char* tag ); /************************************************************************** * * A function to print log data using a custom callback logging function * (which is set using `FT_Set_Log_Handler`). * * This function is defined in `ftdebug.c`. */ FT_BASE( void ) FT_Logging_Callback( const char* fmt, ... ); #endif /* FT_DEBUG_LOGGING */ FT_END_HEADER #endif /* FTDEBUG_H_ */ /* END */