Instead of validating variation axes in every access, OpenType specs
suggest that peak = 0 be used to tag invalid ranges. This implements
just that once during loading.
* src/cff/cffload.c (cff_blend_build_vector): Move the range checks...
(cff_vstore_load): ... here.
* src/truetype/ttgxvar.c (tt_var_get_item_delta): Ditto...
(tt_var_load_item_variation_store): ... ditto.
This should achieve quicker results for common cases.
* src/cff/cffload.c (cff_blend_build_vector): Rearrange conditionals.
* src/truetype/ttgxvar.c (tt_var_get_item_delta): Ditto.
`deltaSet` is an array of packed integers that can be 32 bits, 16 bits, or
8 bits. Before this change, these values were unpacked to 32-bit integers.
However, this can cause big heap allocations, e.g., around 500 KByte for
'NotoSansCJK'. To reduce this amount, store the packed integers and unpack
them just before passing to the calculation. At calculation time, due to
the variable length of region indices, temporary heap allocations are
necessary. This heap allocation is not negligible and visible in `ftbench`
results. So, use stack-allocated arrays for short array calculations.
Fixes#1230.
* include/freetype/internal/ftmmtypes.h (GX_ItemVarDataRec): New fields
`wordDeltaCount` and `longWords`.
* src/truetype/ttgxvar.c (tt_var_load_item_variation_store): Load packed
data.
(tt_var_get_item_delta): Unpack data before applying.
Ensure that all driver functions use the signature of the service or driver.
This avoids pointer mismatches, which are technically undefined behaviour.
Recent compilers are more picky in catching them as part of Control Flow
Integrity tests.
* include/freetype/internal/tttypes.h (TT_FaceRec): New field
`non_var_style_name`.
* src/sfnt/sfobjs.c (sfnt_load_face): Initialize `non_var_style_name`.
(sfnt_done_face): Free `non_var_style_name`.
* src/truetype/ttgxvar.c (TT_Set_Named_Instance): Restore non-VF style name
if switching back to non-VF mode.
A variation font's PostScript name of a named instance is usually different
from the PostScript name of an unnamed instance. However, if a change
between a named instance and an unnamed instance with exactly the same
design axis values happened, it was possible that the PostScript name wasn't
correctly updated.
This commit reorganizes the code to handle this issue within the top-level
API functions, using a new service to trigger recomputation of the
PostScript name.
* include/freetype/internal/services/svmm.h (FT_Construct_PS_Name_Func): New
typedef.
(FT_Service_MultiMasters): New field `construct_ps_name`.
(FT_DEFINE_SERVICE_MULTIMASTERSREC): Updated.
* src/base/ftmm.c (FT_Set_Var_Design_Coordinates,
FT_Set_MM_Blend_Coordinates, FT_Set_Var_Blend_Coordinates): Call
`mm->construct_ps_name` to handle `postscript_name`.
(FT_Set_Named_Instance): Call `mm->construct_ps_name` to handle
`postscript_name`.
Use shortcut.
* src/cff/cffdrivr.c (cff_construct_ps_name): New function.
(cff_service_multi_masters): Updated.
* src/truetype/ttgxvar.c (tt_set_mm_blend): Don't handle `postscript_name`.
(TT_Set_MM_Blend): Simplify.
(TT_Set_Named_Instance): Return -1 if axis values haven't changed.
Don't set `face_index`.
(tt_construct_ps_name): New function.
* src/truetype/ttgxvar.h: Updated.
* src/truetype/ttdriver.c (tt_service_gx_multi_masters): Updated.
* src/type1/t1driver.c (t1_service_multi_masters): Updated.
* src/type1/t1load.c (T1_Set_MM_Blend): Simplify.
According to the documentation, the functions `FT_Set_Named_Instance`,
`FT_Set_MM_Design_Coordinates`, `FT_Set_Var_Design_Coordinates`, and
`FT_Set_Var_Blend_Coordinates` can unset the `FT_FACE_FLAG_VARIATION` flag.
(The same is true for `FT_Set_MM_WeightVector` but this information was
accidentally omitted from the documentation.)
However, if a call of these functions didn't change the axis values this
could fail because internal shortcuts exited too early.
This commit reorganizes the code to handle `FT_FACE_FLAG_VARIATION` in the
top-level API functions, also taking care of the issue at hand.
* src/base/ftmm.c (FT_Set_MM_Design_Coordinates, FT_Set_MM_WeightVector,
FT_Set_Var_Design_Coordinates, FT_Set_MM_Blend_Coordinates,
FT_Set_Var_Blend_Coordinates): Handle `FT_FACE_FLAG_VARIATION`.
* src/truetype/ttgxvar.c (TT_Set_MM_Blend, TT_Set_Var_Design,
TT_Set_Named_Instance) Don't handle `FT_FACE_FLAG_VARIATION`.
* src/type1/t1load.c (T1_Set_MM_Blend, T1_Set_MM_WeightVector,
T1_Set_MM_Design): Ditto.
* src/cff/cffobjs.c (cff_face_init): Use `FT_Set_Named_Instance` instead of
low-level functions.
* src/truetype/ttobjs.c (tt_face_init): Ditto.
This is a generalization of commit
```
commit e6699596af
Author: Werner Lemberg <wl@gnu.org>
Date: Thu Feb 2 11:38:04 2017 +0100
[truetype] Fix MVAR post-action handling.
```
It is also possible for plain `CFF ` style fonts to contain an `fvar` and
`MVAR` table and use `cff_metrics_adjust`. `tt_size_reset` should only be
called with `TT_Size` and never with `CFF_Size`.
Allow the "metrics-variations" service to specify the correct function (if
any) to reset `FT_Size`s after adjusting metrics.
* src/truetype/ttobjs.c (tt_size_reset): Split off some functionality
into...
(tt_size_reset_height): ... this new function.
* src/truetype/ttdriver.c (tt_service_metrics_variations): Add
`size_reset`.
(tt_size_select, tt_size_request): Updated.
* src/truetype/ttobjs.h: Updated.
* include/freetype/internal/services/svmetric.h (MetricsVariations): Add
`size_reset`.
(FT_DEFINE_SERVICE_METRICSVARIATIONSREC): Updated.
* include/freetype/internal/tttypes.h (TT_FaceRec_): Rename `var` to
`tt_var` and add `face_var`.
* src/cff/cffdrivr.c (cff_service_metrics_variations): Add `size_reset`.
(cff_hadvance_adjust, cff_metrics_adjust): Updated.
* src/cff/cffobjs.c (cff_face_init): Use `face_var`.
* src/sfnt/sfobjs.c (sfnt_init_face): Initialize `face_var`.
* src/sfnt/ttmtx.c (tt_face_get_metrics): Use `tt_var`.
* src/truetype/ttgxvar.c (tt_size_reset_iterator): Renamed to...
(ft_size_reset_iterator): ... this new function.
Call `size_reset`.
(tt_apply_mvar): Pass `size_reset` to `ft_size_reset_iterator`.
Fixes#1211
Otherwise we get zillions of clang 15 warnings.
* src/autofit/afcjk.c, src/autofit/afhints.c, src/autofit/aflatin.c,
src/base/ftobjs.c, src/base/ftoutln.c, src/cff/cffparse.c,
src/raster/ftraster.c, src/sfnt/pngshim.c, src/truetype/ttgload.c,
src/truetype/ttgxvar.c, src/truetype/ttobjs.c, src/type1/t1gload.c: Use
`double` cast in debugging and tracing macros.
`tt_var_load_item_variation_store` fills out a `GX_ItemVarStore`. While it
may return an error, the item store must be left in a consistent state so
that any use or destruction of the item store can properly use or free the
data in it. Before this change the counts from the font data were read
directly into the item store before the actual allocation of the arrays to
which they referred. There exist many opportunities between the time the
counts are read and the arrays are allocated to return early due to invalid
data. When this happened the item store claimed to have entires it actually
did not, leading to crashes later when it was used.
Fixes: https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=54449
* src/truetype/ttgxvar.c (tt_var_load_item_variation_store): Read the counts
into local variables and store them in the item store only after the related
arrays are actually created on the item store.
This gives users a possibility to deactivate new features not (yet) in the
OpenType standard.
* include/freetype/config/ftoption.h, devel/ftoption.h
(TT_CONFIG_OPTION_NO_BORING_EXPANSION): New macro.
* src/truetype/ttgxvar.c (ft_var_load_avar): Use it to disable 'avar'
version 2.0 support.
* src/truetype/ttgxvar.c (tt_hvadvance_adjust): Move bounds check ...
(tt_var_get_item_delta): ... to this function, because it is safer. For
example, the 'avar' table 2.0 codepath was not performing a bounds check at
all.
* src/truetype/ttgcvar.c (ft_var_load_hvvar): restore previous behavior
In a previous change [0] the behavior of `ft_var_load_hvvar` was changed
to not load the item variation store if it was at offset 0, but not
return an error when this happened. This broke any users, like
`tt_hvadvance_adjust`, that rely on successful completion of
`ft_var_load_hvvar` to imply that returned table's `itemStore` had been
initialized. This lead such users to dereference NULL.
This change appears to have been unintentional and unrelated to the
actual avar2 changes. As a result, fix these NULL dereferences by
restoring the code to always attempt to initialize the `itemStore`.
[0] ae4eb996 "[truetype] Add support for `avar` table 2.0 format."
Reported as
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=53061
See
https://github.com/harfbuzz/boring-expansion-spec/blob/main/avar2.md
for the specification.
Currently, this is implemented only in most recent OS versions on Apple
platforms and in the HarfBuzz library, but it is expected to be added to the
OpenType standard soon.
* src/truetype/ttgxvar.h (GX_AVarTableRec): New structure.
(GX_BlendRec): Use it to replace `avar_segment` with `avar_table`.
* src/truetype/ttgxvar.c (ft_var_load_avar): Load new table version.
(ft_var_to_normalized, tt_done_blend): Extend for new format.
(ft_var_load_hvvar, ft_var_to_design): Updated.
* src/truetype/ttgxvar.c (TT_Get_MM_Var): Reject retrieving master when
'fvar' values locally do not match with sanitized values from initialization
at `sfnt_init_face` time.
Reported as
https://bugs.chromium.org/p/chromium/issues/detail?id=1360295
Fixes#1172.
* src/sfnt/sfobjs.c (sfnt_load_face): Tag font as Multiple Masters font if
`fvar` is present; do not require other tables to be present.
* src/truetype/ttgxvar.c (tt_set_mm_blend): Allow for a missing 'gvar' table
when setting variation coordinates. However, if a 'gvar' table is actually
present, do perform a sanity check and fail on malformedness.
(TT_Get_MM_Var): Don't assume 'fvar' needs 'gvar' or 'CFF2 tables in all
cases, which is an overly tight check.
* include/freetype/internal/ftmmtypes.h (FT_ItemVarDelta): Make type
explicitly 32-bit.
* include/freetype/internal/services/svmm.h
(FT_Var_Get_Item_Delta_Func): Change return type to `FT_ItemVarDelta`
* truetype/ttgxvar.h (tt_var_get_item_delta): Change return type to
`FT_ItemVarDelta`.
* truetype/ttgxvar.c (tt_var_get_item_delta): Store scalars and deltas
to intermediate array, perform computation using new method
`FT_MulAddFix`.
This formalizes that the phantom points appended in the outline
do not increase its point count, nor are they tagged or included
in any additional contours. Only their coordinates are stored.
They are counted in the glyph zone, however.
* src/truetype/ttgxvar.c (TT_Vary_Apply_Glyph_Deltas): Infer `n_points`
from the outline size plus four phantom points.
* src/truetype/ttgxvar.h (TT_Vary_Apply_Glyph_Deltas): Remove this
argument.
* src/truetype/ttgload.c (tt_prepare_zone): Add phantom four.
(TT_Process_Simple_Glyph, load_truetype_glyph): Update all callers.
This moves phantom point and advance variation adjustment next to
calculations. The logic stays the same, HVAR and VVAR take priority.
* src/truetype/ttgload.c (load_truetype_glyph): Move it from here...
* src/truetype/ttgxvar.c (TT_Vary_Apply_Glyph_Deltas): ... to here
and check for HVAR and VVAR presence outside the main loop.
* src/truetype/ttgload.c (TT_Process_Simple_Glyph, load_truetype_glyph):
Move the advance adjustment from here...
* src/truetype/ttgxvar.c (TT_Vary_Apply_Glyph_Deltas): ... to here and
simplify arguments.
* src/truetype/ttgxvar.h (TT_Vary_Apply_Glyph_Deltas): Update prototype
with fewer arguments.
* include/freetype/internal/ftmmtypes.h (FT_ItemVarDelta): Define type
to be used for delta arrays, upgrade to FT_long.
* src/truetype/ttgxvar.c: Adhere to long_words bit and read either
Short/Byte pairs or Long/Short pairs, as defined by spec. For better
readability, define macro for repetitive read code.
Alexei Podtelezhnikov