Provide C++ versions for public macros with casts.

Many FreeType clients use C++.  However `g++ -Wold-style-cast` warns for
macros with C-style casts even for system header files; this also affects
directories included with `-isystem`.  While this could be seen as a problem
with g++, the problem is more a philosophical one: Over the time, C and C++
diverged more and more, and some features of C are no longer the 'right'
solution in C++.

* include/freetype/config/public-macros.h (FT_STATIC_CAST,
FT_REINTERPRET_CAST): New macros.

* include/freetype/freetype.h (FT_ENC_TAG, FT_LOAD_TARGET_,
FT_LOAD_TARGET_MODE): Use `FT_STATIC_CAST`.
Correctly handle negative 'signed char' input.
* include/freetype/ftimage.h (FT_IMAGE_TAG): Ditto.
* include/freetype/fttypes.h (FT_MAKE_TAG, FT_BOOL): Ditto.
* include/freetype/ftmodapi.h (FT_FACE_DRIVER_NAME): Use
`FT_REINTERPRET_CAST`.

* src/smooth/ftgrays.c (FT_STATIC_CAST)[STANDALONE_]: New macro.
[!STANDALONE]: Include `FT_CONFIG_CONFIG_H`.

Fixes #1116.
This commit is contained in:
Werner Lemberg 2021-11-13 08:53:19 +01:00
parent 238245cd66
commit 9079c5d91a
6 changed files with 43 additions and 26 deletions

View File

@ -103,6 +103,7 @@ FT_BEGIN_HEADER
*/
#define FT_EXPORT( x ) FT_PUBLIC_FUNCTION_ATTRIBUTE extern x
/*
* `FT_UNUSED` indicates that a given parameter is not used -- this is
* only used to get rid of unpleasant compiler warnings.
@ -115,6 +116,18 @@ FT_BEGIN_HEADER
#endif
/*
* Support for casts in both C and C++.
*/
#ifdef __cplusplus
#define FT_STATIC_CAST( type ) static_cast<type>
#define FT_REINTERPRET_CAST( type ) reinterpret_cast<type>
#else
#define FT_STATIC_CAST( type ) (type)
#define FT_REINTERPRET_CAST( type ) (type)
#endif
FT_END_HEADER
#endif /* FREETYPE_CONFIG_PUBLIC_MACROS_H_ */

View File

@ -616,11 +616,12 @@ FT_BEGIN_HEADER
*/
#ifndef FT_ENC_TAG
#define FT_ENC_TAG( value, a, b, c, d ) \
value = ( ( (FT_UInt32)(a) << 24 ) | \
( (FT_UInt32)(b) << 16 ) | \
( (FT_UInt32)(c) << 8 ) | \
(FT_UInt32)(d) )
#define FT_ENC_TAG( value, a, b, c, d ) \
value = ( ( FT_STATIC_CAST( FT_Byte )(a) << 24 ) | \
( FT_STATIC_CAST( FT_Byte )(b) << 16 ) | \
( FT_STATIC_CAST( FT_Byte )(c) << 8 ) | \
FT_STATIC_CAST( FT_Byte )(d) )
#endif /* FT_ENC_TAG */
@ -3181,7 +3182,7 @@ FT_BEGIN_HEADER
* necessary to empty the cache after a mode switch to avoid false hits.
*
*/
#define FT_LOAD_TARGET_( x ) ( (FT_Int32)( (x) & 15 ) << 16 )
#define FT_LOAD_TARGET_( x ) ( FT_STATIC_CAST( FT_Int32 )( (x) & 15 ) << 16 )
#define FT_LOAD_TARGET_NORMAL FT_LOAD_TARGET_( FT_RENDER_MODE_NORMAL )
#define FT_LOAD_TARGET_LIGHT FT_LOAD_TARGET_( FT_RENDER_MODE_LIGHT )
@ -3200,7 +3201,8 @@ FT_BEGIN_HEADER
* @FT_LOAD_TARGET_XXX value.
*
*/
#define FT_LOAD_TARGET_MODE( x ) ( (FT_Render_Mode)( ( (x) >> 16 ) & 15 ) )
#define FT_LOAD_TARGET_MODE( x ) \
FT_STATIC_CAST( FT_Render_Mode )( ( (x) >> 16 ) & 15 )
/**************************************************************************

View File

@ -28,11 +28,6 @@
#define FTIMAGE_H_
/* STANDALONE_ is from ftgrays.c */
#ifndef STANDALONE_
#endif
FT_BEGIN_HEADER
@ -700,11 +695,13 @@ FT_BEGIN_HEADER
* to get a simple enumeration without assigning special numbers.
*/
#ifndef FT_IMAGE_TAG
#define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) \
value = ( ( (unsigned long)_x1 << 24 ) | \
( (unsigned long)_x2 << 16 ) | \
( (unsigned long)_x3 << 8 ) | \
(unsigned long)_x4 )
#define FT_IMAGE_TAG( value, _x1, _x2, _x3, _x4 ) \
value = ( ( FT_STATIC_CAST( unsigned char )( _x1 ) << 24 ) | \
( FT_STATIC_CAST( unsigned char )( _x2 ) << 16 ) | \
( FT_STATIC_CAST( unsigned char )( _x3 ) << 8 ) | \
FT_STATIC_CAST( unsigned char )( _x4 ) )
#endif /* FT_IMAGE_TAG */

View File

@ -347,8 +347,9 @@ FT_BEGIN_HEADER
* 2.11
*
*/
#define FT_FACE_DRIVER_NAME( face ) \
( ( *(FT_Module_Class**)( ( face )->driver ) )->module_name )
#define FT_FACE_DRIVER_NAME( face ) \
( ( *FT_REINTERPRET_CAST( FT_Module_Class** ) \
( ( face )->driver ) )->module_name )
/**************************************************************************

View File

@ -485,12 +485,12 @@ FT_BEGIN_HEADER
* The produced values **must** be 32-bit integers. Don't redefine this
* macro.
*/
#define FT_MAKE_TAG( _x1, _x2, _x3, _x4 ) \
(FT_Tag) \
( ( (FT_ULong)_x1 << 24 ) | \
( (FT_ULong)_x2 << 16 ) | \
( (FT_ULong)_x3 << 8 ) | \
(FT_ULong)_x4 )
#define FT_MAKE_TAG( _x1, _x2, _x3, _x4 ) \
FT_STATIC_CAST( FT_Tag ) \
( ( FT_STATIC_CAST( FT_Byte )( _x1 ) << 24 ) | \
( FT_STATIC_CAST( FT_Byte )( _x2 ) << 16 ) | \
( FT_STATIC_CAST( FT_Byte )( _x3 ) << 8 ) | \
FT_STATIC_CAST( FT_Byte )( _x4 ) )
/*************************************************************************/
@ -588,7 +588,7 @@ FT_BEGIN_HEADER
#define FT_IS_EMPTY( list ) ( (list).head == 0 )
#define FT_BOOL( x ) ( (FT_Bool)( (x) != 0 ) )
#define FT_BOOL( x ) FT_STATIC_CAST( FT_Bool )( (x) != 0 )
/* concatenate C tokens */
#define FT_ERR_XCAT( x, y ) x ## y

View File

@ -152,6 +152,8 @@
#define ADD_INT( a, b ) \
(int)( (unsigned int)(a) + (unsigned int)(b) )
#define FT_STATIC_CAST( type ) (type)
#define ft_memset memset
@ -273,6 +275,8 @@ typedef ptrdiff_t FT_PtrDist;
#else /* !STANDALONE_ */
#include <ft2build.h>
#include FT_CONFIG_CONFIG_H
#include "ftgrays.h"
#include <freetype/internal/ftobjs.h>
#include <freetype/internal/ftdebug.h>