/****************************************************************************
*
* ftdebug.c
*
* Debugging and logging component (body).
*
* Copyright (C) 1996-2023 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.
*
*/
/**************************************************************************
*
* This component contains various macros and functions used to ease the
* debugging of the FreeType engine. Its main purpose is in assertion
* checking, tracing, and error detection.
*
* There are now three debugging modes:
*
* - trace mode
*
* Error and trace messages are sent to the log file (which can be the
* standard error output).
*
* - error mode
*
* Only error messages are generated.
*
* - release mode:
*
* No error message is sent or generated. The code is free from any
* debugging parts.
*
*/
#include <freetype/freetype.h>
#include <freetype/ftlogging.h>
#include <freetype/internal/ftdebug.h>
#include <freetype/internal/ftobjs.h>
#ifdef FT_DEBUG_LOGGING
/**************************************************************************
*
* Variables used to control logging.
*
* 1. `ft_default_trace_level` stores the value of trace levels, which are
* provided to FreeType using the `FT2_DEBUG` environment variable.
*
* 2. `ft_fileptr` stores the `FILE*` handle.
*
* 3. `ft_component` is a string that holds the name of `FT_COMPONENT`.
*
* 4. The flag `ft_component_flag` prints the name of `FT_COMPONENT` along
* with the actual log message if set to true.
*
* 5. The flag `ft_timestamp_flag` prints time along with the actual log
* message if set to ture.
*
* 6. `ft_have_newline_char` is used to differentiate between a log
* message with and without a trailing newline character.
*
* 7. `ft_custom_trace_level` stores the custom trace level value, which
* is provided by the user at run-time.
*
* We use `static` to avoid 'unused variable' warnings.
*
*/
static const char* ft_default_trace_level = NULL;
static FILE* ft_fileptr = NULL;
static const char* ft_component = NULL;
static FT_Bool ft_component_flag = FALSE;
static FT_Bool ft_timestamp_flag = FALSE;
static FT_Bool ft_have_newline_char = TRUE;
static const char* ft_custom_trace_level = NULL;
/* declared in ftdebug.h */
dlg_handler ft_default_log_handler = NULL;
FT_Custom_Log_Handler custom_output_handler = NULL;
#endif /* FT_DEBUG_LOGGING */
#ifdef FT_DEBUG_LEVEL_ERROR
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
FT_Message( const char* fmt,
... )
{
va_list ap;
va_start( ap, fmt );
vfprintf( stderr, fmt, ap );
va_end( ap );
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
FT_Panic( const char* fmt,
... )
{
va_list ap;
va_start( ap, fmt );
vfprintf( stderr, fmt, ap );
va_end( ap );
exit( EXIT_FAILURE );
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( int )
FT_Throw( FT_Error error,
int line,
const char* file )
{
#if 0
/* activating the code in this block makes FreeType very chatty */
fprintf( stderr,
"%s:%d: error 0x%02x: %s\n",
file,
line,
error,
FT_Error_String( error ) );
#else
FT_UNUSED( error );
FT_UNUSED( line );
FT_UNUSED( file );
#endif
return 0;
}
#endif /* FT_DEBUG_LEVEL_ERROR */
#ifdef FT_DEBUG_LEVEL_TRACE
/* array of trace levels, initialized to 0; */
/* this gets adjusted at run-time */
static int ft_trace_levels_enabled[trace_count];
/* array of trace levels, always initialized to 0 */
static int ft_trace_levels_disabled[trace_count];
/* a pointer to either `ft_trace_levels_enabled' */
/* or `ft_trace_levels_disabled' */
int* ft_trace_levels;
/* define array of trace toggle names */
#define FT_TRACE_DEF( x ) #x ,
static const char* ft_trace_toggles[trace_count + 1] =
{
#include <freetype/internal/fttrace.h>
NULL
};
#undef FT_TRACE_DEF
/* documentation is in ftdebug.h */
FT_BASE_DEF( FT_Int )
FT_Trace_Get_Count( void )
{
return trace_count;
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( const char * )
FT_Trace_Get_Name( FT_Int idx )
{
int max = FT_Trace_Get_Count();
if ( idx < max )
return ft_trace_toggles[idx];
else
return NULL;
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
FT_Trace_Disable( void )
{
ft_trace_levels = ft_trace_levels_disabled;
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
FT_Trace_Enable( void )
{
ft_trace_levels = ft_trace_levels_enabled;
}
/**************************************************************************
*
* Initialize the tracing sub-system. This is done by retrieving the
* value of the `FT2_DEBUG' environment variable. It must be a list of
* toggles, separated by spaces, `;', or `,'. Example:
*
* export FT2_DEBUG="any:3 memory:7 stream:5"
*
* This requests that all levels be set to 3, except the trace level for
* the memory and stream components which are set to 7 and 5,
* respectively.
*
* See the file `include/freetype/internal/fttrace.h' for details of
* the available toggle names.
*
* The level must be between 0 and 7; 0 means quiet (except for serious
* runtime errors), and 7 means _very_ verbose.
*/
FT_BASE_DEF( void )
ft_debug_init( void )
{
const char* ft2_debug = NULL;
#ifdef FT_DEBUG_LOGGING
if ( ft_custom_trace_level != NULL )
ft2_debug = ft_custom_trace_level;
else
ft2_debug = ft_default_trace_level;
#else
ft2_debug = ft_getenv( "FT2_DEBUG" );
#endif
if ( ft2_debug )
{
const char* p = ft2_debug;
const char* q;
for ( ; *p; p++ )
{
/* skip leading whitespace and separators */
if ( *p == ' ' || *p == '\t' || *p == ',' || *p == ';' || *p == '=' )
continue;
#ifdef FT_DEBUG_LOGGING
/* check extra arguments for logging */
if ( *p == '-' )
{
const char* r = ++p;
if ( *r == 'v' )
{
const char* s = ++r;
ft_component_flag = TRUE;
if ( *s == 't' )
{
ft_timestamp_flag = TRUE;
p++;
}
p++;
}
else if ( *r == 't' )
{
const char* s = ++r;
ft_timestamp_flag = TRUE;
if ( *s == 'v' )
{
ft_component_flag = TRUE;
p++;
}
p++;
}
}
#endif /* FT_DEBUG_LOGGING */
/* read toggle name, followed by ':' */
q = p;
while ( *p && *p != ':' )
p++;
if ( !*p )
break;
if ( *p == ':' && p > q )
{
FT_Int n, i, len = (FT_Int)( p - q );
FT_Int level = -1, found = -1;
for ( n = 0; n < trace_count; n++ )
{
const char* toggle = ft_trace_toggles[n];
for ( i = 0; i < len; i++ )
{
if ( toggle[i] != q[i] )
break;
}
if ( i == len && toggle[i] == 0 )
{
found = n;
break;
}
}
/* read level */
p++;
if ( *p )
{
level = *p - '0';
if ( level < 0 || level > 7 )
level = -1;
}
if ( found >= 0 && level >= 0 )
{
if ( found == trace_any )
{
/* special case for `any' */
for ( n = 0; n < trace_count; n++ )
ft_trace_levels_enabled[n] = level;
}
else
ft_trace_levels_enabled[found] = level;
}
}
}
}
ft_trace_levels = ft_trace_levels_enabled;
}
#else /* !FT_DEBUG_LEVEL_TRACE */
FT_BASE_DEF( void )
ft_debug_init( void )
{
/* nothing */
}
FT_BASE_DEF( FT_Int )
FT_Trace_Get_Count( void )
{
return 0;
}
FT_BASE_DEF( const char * )
FT_Trace_Get_Name( FT_Int idx )
{
FT_UNUSED( idx );
return NULL;
}
FT_BASE_DEF( void )
FT_Trace_Disable( void )
{
/* nothing */
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
FT_Trace_Enable( void )
{
/* nothing */
}
#endif /* !FT_DEBUG_LEVEL_TRACE */
#ifdef FT_DEBUG_LOGGING
/**************************************************************************
*
* Initialize and de-initialize 'dlg' library.
*
*/
FT_BASE_DEF( void )
ft_logging_init( void )
{
ft_default_log_handler = ft_log_handler;
ft_default_trace_level = ft_getenv( "FT2_DEBUG" );
if ( ft_getenv( "FT_LOGGING_FILE" ) )
ft_fileptr = ft_fopen( ft_getenv( "FT_LOGGING_FILE" ), "w" );
else
ft_fileptr = stderr;
ft_debug_init();
/* Set the default output handler for 'dlg'. */
dlg_set_handler( ft_default_log_handler, NULL );
}
FT_BASE_DEF( void )
ft_logging_deinit( void )
{
if ( ft_fileptr != stderr )
ft_fclose( ft_fileptr );
}
/**************************************************************************
*
* An output log handler for FreeType.
*
*/
FT_BASE_DEF( void )
ft_log_handler( const struct dlg_origin* origin,
const char* string,
void* data )
{
char features_buf[128];
char* bufp = features_buf;
FT_UNUSED( data );
if ( ft_have_newline_char )
{
const char* features = NULL;
size_t features_length = 0;
#define FEATURES_TIMESTAMP "[%h:%m] "
#define FEATURES_COMPONENT "[%t] "
#define FEATURES_TIMESTAMP_COMPONENT "[%h:%m %t] "
if ( ft_timestamp_flag && ft_component_flag )
{
features = FEATURES_TIMESTAMP_COMPONENT;
features_length = sizeof ( FEATURES_TIMESTAMP_COMPONENT );
}
else if ( ft_timestamp_flag )
{
features = FEATURES_TIMESTAMP;
features_length = sizeof ( FEATURES_TIMESTAMP );
}
else if ( ft_component_flag )
{
features = FEATURES_COMPONENT;
features_length = sizeof ( FEATURES_COMPONENT );
}
if ( ft_component_flag || ft_timestamp_flag )
{
ft_strncpy( features_buf, features, features_length );
bufp += features_length - 1;
}
if ( ft_component_flag )
{
size_t tag_length = ft_strlen( *origin->tags );
size_t i;
/* To vertically align tracing messages we compensate the */
/* different FT_COMPONENT string lengths by inserting an */
/* appropriate amount of space characters. */
for ( i = 0;
i < FT_MAX_TRACE_LEVEL_LENGTH - tag_length;
i++ )
*bufp++ = ' ';
}
}
/* Finally add the format string for the tracing message. */
*bufp++ = '%';
*bufp++ = 'c';
*bufp = '\0';
dlg_generic_outputf_stream( ft_fileptr,
(const char*)features_buf,
origin,
string,
dlg_default_output_styles,
true );
if ( ft_strrchr( string, '\n' ) )
ft_have_newline_char = TRUE;
else
ft_have_newline_char = FALSE;
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
ft_add_tag( const char* tag )
{
ft_component = tag;
dlg_add_tag( tag, NULL );
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
ft_remove_tag( const char* tag )
{
dlg_remove_tag( tag, NULL );
}
/* documentation is in ftlogging.h */
FT_EXPORT_DEF( void )
FT_Trace_Set_Level( const char* level )
{
ft_component_flag = FALSE;
ft_timestamp_flag = FALSE;
ft_custom_trace_level = level;
ft_debug_init();
}
/* documentation is in ftlogging.h */
FT_EXPORT_DEF( void )
FT_Trace_Set_Default_Level( void )
{
ft_component_flag = FALSE;
ft_timestamp_flag = FALSE;
ft_custom_trace_level = NULL;
ft_debug_init();
}
/**************************************************************************
*
* Functions to handle a custom log handler.
*
*/
/* documentation is in ftlogging.h */
FT_EXPORT_DEF( void )
FT_Set_Log_Handler( FT_Custom_Log_Handler handler )
{
custom_output_handler = handler;
}
/* documentation is in ftlogging.h */
FT_EXPORT_DEF( void )
FT_Set_Default_Log_Handler( void )
{
custom_output_handler = NULL;
}
/* documentation is in ftdebug.h */
FT_BASE_DEF( void )
FT_Logging_Callback( const char* fmt,
... )
{
va_list ap;
va_start( ap, fmt );
custom_output_handler( ft_component, fmt, ap );
va_end( ap );
}
#else /* !FT_DEBUG_LOGGING */
FT_EXPORT_DEF( void )
FT_Trace_Set_Level( const char* level )
{
FT_UNUSED( level );
}
FT_EXPORT_DEF( void )
FT_Trace_Set_Default_Level( void )
{
/* nothing */
}
FT_EXPORT_DEF( void )
FT_Set_Log_Handler( FT_Custom_Log_Handler handler )
{
FT_UNUSED( handler );
}
FT_EXPORT_DEF( void )
FT_Set_Default_Log_Handler( void )
{
/* nothing */
}
#endif /* !FT_DEBUG_LOGGING */
/* END */
