walkero
/
harfbuzz
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[ot-face] Load num-glyphs from `loca` table before `maxp` 

Implements [boring-expansion] [maxp] Relax
https://github.com/be-fonts/boring-expansion-spec/issues/6
This commit is contained in:
Behdad Esfahbod 2022-02-02 14:10:16 -06:00
parent 93962977bc
commit ed6d287d11
6 changed files with 127 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/hb-ot-hmtx-table.hh
View File

@ -185,7 +185,7 @@ struct hmtxvmtx
table = hb_sanitize_context_t ().reference_table<hmtxvmtx> (face, T::tableTag);
/* Cap num_metrics() and num_advances() based on table length. */
/* Cap num_metrics and num_advances based on table length. */
unsigned int len = table.get_length ();
if (unlikely (num_advances * 4 > len))
num_advances = len / 4;

54
src/hb-static.cc
View File

@ -33,6 +33,7 @@
#include "hb-aat-layout-feat-table.hh"
#include "hb-ot-layout-common.hh"
#include "hb-ot-cmap-table.hh"
#include "hb-ot-glyf-table.hh"
#include "hb-ot-head-table.hh"
#include "hb-ot-maxp-table.hh"
@ -55,17 +56,58 @@ const unsigned char _hb_Null_AAT_Lookup[2] = {0xFF, 0xFF};
/* hb_face_t */
static inline unsigned
load_num_glyphs_from_loca (const hb_face_t *face)
{
unsigned ret = 0;
hb_sanitize_context_t c = hb_sanitize_context_t ();
c.set_num_glyphs (0); /* So we don't recurse ad infinitum. */
/* We cannot use table.head because that would use sanitizer,
* which would try accessing face.num_glyphs, which would
* recurse here again... */
hb_blob_t *head_blob = c.reference_table<OT::head> (face);
const OT::head *head_table = head_blob->as<OT::head> ();
unsigned indexToLocFormat = head_table->indexToLocFormat;
hb_blob_destroy (head_blob);
if (indexToLocFormat <= 1)
{
bool short_offset = 0 == indexToLocFormat;
hb_blob_t *loca_blob = c.reference_table<OT::loca> (face);
ret = hb_max (1u, loca_blob->length / (short_offset ? 2 : 4)) - 1;
hb_blob_destroy (loca_blob);
}
return ret;
}
static inline unsigned
load_num_glyphs_from_maxp (const hb_face_t *face)
{
unsigned ret = 0;
hb_sanitize_context_t c = hb_sanitize_context_t ();
c.set_num_glyphs (0); /* So we don't recurse ad infinitum. */
hb_blob_t *maxp_blob = c.reference_table<OT::maxp> (face);
const OT::maxp *maxp_table = maxp_blob->as<OT::maxp> ();
ret = maxp_table->get_num_glyphs ();
hb_blob_destroy (maxp_blob);
return ret;
}
unsigned int
hb_face_t::load_num_glyphs () const
{
hb_sanitize_context_t c = hb_sanitize_context_t ();
c.set_num_glyphs (0); /* So we don't recurse ad infinitum. */
hb_blob_t *maxp_blob = c.reference_table<OT::maxp> (this);
const OT::maxp *maxp_table = maxp_blob->as<OT::maxp> ();
unsigned ret = 0;
ret = load_num_glyphs_from_loca (this);
if (!ret)
ret = load_num_glyphs_from_maxp (this);
unsigned int ret = maxp_table->get_num_glyphs ();
num_glyphs.set_relaxed (ret);
hb_blob_destroy (maxp_blob);
return ret;
}

1
test/api/Makefile.am
View File

@ -30,6 +30,7 @@ noinst_PROGRAMS = $(TEST_PROGS)
TEST_PROGS = \
test-aat-layout \
test-baseline \
test-be-num-glyphs \
test-blob \
test-buffer \
test-c \

7
test/api/hb-test.h
View File

@ -52,6 +52,13 @@ HB_BEGIN_DECLS
((const char *) s)[2], \
((const char *) s)[3]))
#define HB_FACE_ADD_TABLE(face, tag, data) \
hb_face_builder_add_table ((face), \
HB_TAG_CHAR4(tag), \
hb_blob_create_or_fail ((data), \
sizeof (data), \
HB_MEMORY_MODE_READONLY, \
NULL, NULL))
static inline const char *
srcdir (void)

1
test/api/meson.build
View File

@ -6,6 +6,7 @@ endif
tests = [
'test-aat-layout.c',
'test-baseline.c',
'test-be-num-glyphs.c',
'test-blob.c',
'test-buffer.c',
'test-c.c',

69
test/api/test-be-num-glyphs.c Normal file
View File

@ -0,0 +1,69 @@
/*
* Copyright © 2022 Behdad Esfahbod
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*/
#include "hb-test.h"
#include <hb.h>
static void
test_maxp_and_loca (void)
{
hb_face_t *face;
const char maxp_data[] = "\x00\x00\x50\x00" // version
"\x00\x05" // numGlyphs
;
const char loca_data[18] = "";
face = hb_face_builder_create ();
g_assert_cmpuint (hb_face_get_glyph_count (face), ==, 0);
hb_face_destroy (face);
face = hb_face_builder_create ();
HB_FACE_ADD_TABLE (face, "maxp", maxp_data);
g_assert_cmpuint (hb_face_get_glyph_count (face), ==, 5);
hb_face_destroy (face);
face = hb_face_builder_create ();
HB_FACE_ADD_TABLE (face, "maxp", maxp_data);
HB_FACE_ADD_TABLE (face, "loca", loca_data);
g_assert_cmpuint (hb_face_get_glyph_count (face), ==, 8);
hb_face_destroy (face);
face = hb_face_builder_create ();
HB_FACE_ADD_TABLE (face, "loca", loca_data);
g_assert_cmpuint (hb_face_get_glyph_count (face), ==, 8);
hb_face_destroy (face);
}
int
main (int argc, char **argv)
{
hb_test_init (&argc, &argv);
hb_test_add (test_maxp_and_loca);
return hb_test_run();
}