I am currently trying to compile FreeType for CHERI-extended ISAs
(CHERI-RISC-V and Arm's Morello), but I am getting compiler warnings
from the `FT_UINT_TO_POINTER` macro. When compiling with the CHERI
Clang compiler, not using `uinptr_t` for casts between integers an
pointers results in the following `-Werror` build failures:
```
In file included from .../src/truetype/truetype.c:22:
.../src/truetype/ttgload.c:1925:22: error:
cast from provenance-free integer type to pointer type will
give pointer that can not be dereferenced
[-Werror,-Wcheri-capability-misuse]
node->data = FT_UINT_TO_POINTER( glyph_index );
^
.../include/freetype/internal/compiler-macros.h:79:34: note:
expanded from macro 'FT_UINT_TO_POINTER'
```
* include/freetype/internal/compiler-macros.h (FT_UINT_TO_POINTER):
The ISO C standard compliant fix for this would be to use
`uintptr_t` from `stdint.h`, but I am not sure if this is supported
by the minimum compiler version. Therefore, use the
compiler-defined `__UINTPTR_TYPE__` macro (supported in GCC 4.6+ and
Clang since about 3.0) before checking for `_WIN64` and falling back
to `unsigned long`.
This was already true (though undocumented) most of the time, but
not if `FT_NEW` inside `FT_Stream_New` failed or if the
`FT_OPEN_XXX` flags were bad.
Normally, `FT_Open_Face` calls `FT_Stream_New`, which returns the
user-supplied stream unchanged, and in case of any subsequent error
in `FT_Open_Face`, the stream is closed via `FT_Stream_Free`.
Up to now, however, `FT_Stream_New` allocates a new stream even if
it is already given one by the user. If this allocation fails, the
user-supplied stream is not returned to `FT_Open_Face` and never
closed. Moreover, the user cannot detect this situation: all they
see is that `FT_Open_Face` returns `FT_Err_Out_Of_Memory`, but that
can also happen after a different allocation fails within the main
body of `FT_Open_Face`, when the user's stream has already been
closed by `FT_Open_Face`. It is plausible that the user stream's
`close` method frees memory allocated for the stream object itself,
so the user cannot defensively free it upon `FT_Open_Face` failure
lest it ends up doubly freed. All in all, this ends up leaking the
memory/resources used by user's stream.
Furthermore, `FT_Stream_New` simply returns an error if the
`FT_OPEN_XXX` flags are unsupported, which can mean either an
invalid combination of flags or a perfectly innocent
`FT_OPEN_STREAM` on a FreeType build that lacks stream support.
With this patch, the user-supplied stream is closed even in these
cases, so the user can be sure that if `FT_Open_Face` failed, the
stream is definitely closed.
* src/base/ftobjs.c (FT_Stream_New): Don't allocate a buffer
unnecessarily.
Move error-handling code to make the control flow more obvious.
Close user-supplied stream if the flags are unsupported.
`FT_Stream_Open` always sets `pathname.pointer`, so remove the
redundant (re)assignment. None of the `FT_Stream_Open...` functions
uses `stream->memory`, so keep just one assignment at the end,
shared among all possible control flow paths.
('Unsupported flags' that may need a stream closure can be either an
invalid combination of multiple `FT_OPEN_XXX` mode flags or a clean
`FT_OPEN_STREAM` flag on a FreeType build that lacks stream
support.)
The three modes are mutually exclusive, and the documentation of the
`FT_OPEN_XXX` constants notes this. However, there was no check to
validate this in the code, and the documentation on `FT_Open_Args`
claimed that the corresponding bits were checked in a well-defined
order, implying it was valid (if useless) to specify more than one.
Ironically, this documented order did not agree with the actual
code, so it could not be relied upon; hopefully, nobody did this and
nobody will be hurt by the new validation.
Even if multiple mode bits were allowed, they could cause memory
leaks: if both `FT_OPEN_STREAM` and `stream` are set along with
either `FT_OPEN_MEMORY` or `FT_OPEN_PATHNAME`, then `FT_Stream_New`
allocated a new stream but `FT_Open_Face` marked it as an 'external'
stream, so the stream object was never released.
* src/base/ftobjs.c (FT_Stream_New): Reject incompatible
`FT_OPEN_XXX` flags.
This feature was always experimental, and probably nevery worked
properly. This patch completely removes it from the source code,
except for a documentation block describing it for historical
purpose.
This code has always been experimental and was never compiled
anyway (FT_OPTION_AUTOFIT2 does not appear in ftoption.h or even
any of our build files).
Some practical debugging work has shown that displaying level X of
an `FT_TRACEX` macro in the output of `FT2_DEBUG="... -v"` would be
very helpful to find out which trace level should be selected. As
an example, we now get output like
```
[ttobjs:2] TTF driver
[ttobjs:2] SFNT driver
[sfobjs:2] not a font using the SFNT container format
[t1objs:2] Type 1 driver
[stream:7] FT_Stream_EnterFrame: 14 bytes
```
* include/freetype/internal/ftdebug.h (FT_LOGGING_TAGX): New macro.
(FT_LOG): Use it to add the trace level to the logging tag.
* include/freetype/internal/fttrace.h (FT_MAX_TRACE_LEVEL_LENGTH):
Adjust.
* docs/DEBUG: Updated.
* include/freetype/ftcolor.h (FT_PaintTransformed, FT_PaintFormat,
FT_COLR_Paint): Do it to make it harmonize with other names such as
'PaintTranslate'.
* src/sfnt/ttcolr.c (read_paint, tt_face_get_paint): Ditto.
* include/freetype/freetype.h: Cut section layer managament
containing 'COLR' v0 and v1 API and move it to `ftcolor.h` as
requested by Werner on freetype-devel.
* include/freetype/ftcolor.h: Paste that section.
Since 8-bits is enough to represent SDF data we no longer require
16-bits for this purpose. Also, we now normalize the output data
to use the entire 8-bit range efficiently. For example: if we use
3.5 format with a spread of 1 we basically only use the starting
5-bits. By normalizing we can use the entire 8-bit range.
* include/freetype/freetype.h (FT_Render_Mode): Updated description
for `FT_RENDER_MODE_SDF` regarding this change.
* include/freetype/ftimage.h (FT_Pixel_Mode): Removed
`FT_PIXEL_MODE_GRAY16` since no longer required.
* include/freetype/fttypes.h (FT_F6Dot10): Removed since no longer
required.
* src/sdf/ftsdfrend.c (ft_sdf_render, ft_bsdf_render): Allocate 8-bit
bitmap instead of 16-bit buffer.
* src/sdf/ftsdfcommon.h (map_fixed_to_sdf): Added function to convert
16.16 distance value to our desired format.
* src/sdf/ftsdf.c (sdf_generate_with_overlaps,
sdf_generate_bounding_box): Use the new `map_fixed_to_sdf` function
and also use 8-bit output buffer.
* src/sdf/ftbsdf.c (finalize_sdf): Output to a 8-bit buffer instead
of 16-bit buffer.
* freetype.h (FT_PaintFormat): Update paint format identifiers after
a specification change. The specification was updated to have
sibling formats, variable and non-variable variants for each.
Reflect that here.
* sfnt/ttcolr.c (read_paint): Remove parsing of variable indices as
the non-variable formats no longer have them.
* include/freetype/internal/compiler-macros.h (FT_COMPARE_DEF):
Add new macro.
* src/base/ftrfork.c, src/bdf/bdflib.c, src/gxvalid/gxvcommn.c,
src/psaux/afmparse.c, src/psnames/psmodule.c, src/type1/t1afm.c,
src/sfnt/sfwoff.c, src/sfnt/sfwoff2.c: Update qsort callbacks.
Fixes#1026 when compiling FreeType with an unusual calling convention
while the C library qsort still expects cdecl.
* include/freetype/freetype.h (FT_Get_Color_Glyph_Paint):
Additional function argument root_transform to control whether
root transform should be returned.
(FT_OpaquePaint): Additional tracking field to denote whether
root transform is to be returned.
* include/freetype/internal/sfnt.h
(TT_Get_Color_Glyph_Paint_Func): Propagate additional argument.
* src/base/ftobjs.c (FT_Get_Color_Glyph_Paint): Ditto.
* src/sfnt/ttcolr.c (tt_face_get_colr_glyph_paint): Return root
transform reflecting the size and tranform configured on
FT_Face.
(read_paint): Initialize and track status of insert_root_transform
flag.
It's easier to have stubs if FT_DEBUG_LOGGING is undefined than to
modify `ftexport.sym` conditionally.
Problem reported by Alexei.
* src/base/ftdebug.c: Include `ftlogging.h`.
(FT_Trace_Set_Level, FT_Trace_Set_Default_Level, FT_Set_Log_Handler,
FT_Set_Default_Log_Handler) [!FT_DEBUG_LOGGING]: Provide stubs.
* include/freetype/config/ftoption.h (TT_SUPPORT_COLRV1): New macro
so that clients can test whether the FreeType checkout that they are
building against supports the 'COLR' v1 API. This is intended to be
a temporary solution until 'COLR' v1 support is released in a
FreeType version and such a check can be made by using the version
number instead.
* include/freetype/internal/sfnt.h (TT_Get_Color_Glyph_Paint_Func,
TT_Get_Paint_Layers_Func, TT_Get_Colorline_Stops_Func,
TT_Get_Paint_Func): New function pointer types.
(SFNT_Interface): Add them.
(FT_DEFINE_SFNT_INTERFACE): Updated.
* src/sfnt/sfdriver.c (PUT_COLOR_LAYERS_V1): New macro.
(sfnt_interface): Add new function pointers.
* include/freetype/freetype.h (FT_Get_Color_Glyph_Paint): New method
for retrieving the root paint object for a color glyph by specifying
a glyph ID.
(FT_Get_Paint_Layers): New method for retrieving the layers of a
`PaintColorGlyph`.
(FT_Get_ColorLine_Stops): New method for retrieving the stops of a
color.
(FT_Get_Paint): New method for resolving an `FT_OpaquePaint` into an
`FT_COLR_Paint` object.
* include/freetype/freetype.h (FT_PaintFormat, FT_ColorStopIterator,
FT_ColorIndex, FT_ColorStop, FT_PaintExtend, FT_ColorLine,
FT_Affine23, FT_CompositeMode, FT_OpaquePaint, FT_PaintColrLayers,
FT_PaintSolid, FT_PaintLinearGradient, FT_PaintRadialGradient,
FT_PaintGlyph, FT_PaintColrGlyph, FT_PaintTransformed,
FT_PaintTranslate, FT_PaintRotate, FT_PaintSkew, FT_PaintComposite,
FT_COLR_Paint): Adding structs and enum to represent paint format,
color stop information, gradient extend information, structs to
reference paint offsets, and to define transforms and compositions.
Adding a union type to represent the union of the structs,
distinguished by `FT_PaintFormat`.
* include/freetype/config/ftmodule.h: Add both the 'sfd' and 'bsfd'
renderers to the list of modules.
* CMakeLists.txt (BASE_SRCS): Add 'sdf' single-object module.
* src/sdf/module.mk, src/sfd/rules.mk: New files.
* src/sdf/ftsdf.h (ft_sdf_raster): New forward declaration.
* include/freetype/ftmoderr.h (FT_MODERRDEF): Add error definition
for the 'sdf' module.
* include/freetype/internal/fttrace.h (FT_TRACE_DEF): Add trace
definition for the `sdf' module.
* modules.cfg (RASTER_MODULES): Add the `sdf' module to the list of
rasterizers.
* include/freetype/freetype.h (FT_Render_Mode): Add new render mode
`FT_RENDER_MODE_SDF`, which will be used to generate SDF.
* include/freetype/ftimage.h (FT_Pixel_Mode): Add new pixel mode
`FT_PIXEL_MODE_GRAY16`, which will be the output of the 'sdf'
module.
(FT_RASTER_FLAG_SDF): New raster flag to be used internally by the
'sdf' module.
* include/freetype/fttypes.h (FT_F6Dot10): New data type.
* src/truetype/ttgload.c (tt_get_metrics, load_truetype_glyph):
Previously, the code would populate the phantom points before
calling the `get_glyph_metrics` callback. For formats like PCL XL
format 1, class 2 downloaded fonts (where metrics are removed from
the TTF header), this causes problems when the hinting program uses
the phantom points (misplaced and distorted glyphs) due to the
metrics being unset (all zeros).
(tt_get_metrics_incr_overrides): Renamed to...
(tt_get_metrics_incremental): ... this. Updated caller
* include/freetype/ftincrem.h: Update the documentation to make it
clearer that `get_glyph_metrics` is to retrieve metrics from a
non-standard source, but *not* for the purpose of imposing custom
metrics.
Alex Richardson