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-rw-r--r--Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc117
1 files changed, 114 insertions, 3 deletions
diff --git a/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc
index 31ddb4f8940..428a9dd1286 100644
--- a/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc
+++ b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-subset.cc
@@ -78,6 +78,108 @@ using OT::Layout::GSUB::GSUB;
* retain glyph ids option and configure the subset to pass through the layout tables untouched.
*/
+/*
+ * The list of tables in the open type spec. Used to check for tables that may need handling
+ * if we are unable to list the tables in a face.
+ */
+static hb_tag_t known_tables[] {
+ HB_TAG ('a', 'v', 'a', 'r'),
+ HB_OT_TAG_BASE,
+ HB_OT_TAG_CBDT,
+ HB_OT_TAG_CBLC,
+ HB_OT_TAG_cff1,
+ HB_OT_TAG_cff2,
+ HB_OT_TAG_cmap,
+ HB_OT_TAG_COLR,
+ HB_OT_TAG_CPAL,
+ HB_TAG ('c', 'v', 'a', 'r'),
+ HB_TAG ('c', 'v', 't', ' '),
+ HB_TAG ('D', 'S', 'I', 'G'),
+ HB_TAG ('E', 'B', 'D', 'T'),
+ HB_TAG ('E', 'B', 'L', 'C'),
+ HB_TAG ('E', 'B', 'S', 'C'),
+ HB_TAG ('f', 'p', 'g', 'm'),
+ HB_TAG ('f', 'v', 'a', 'r'),
+ HB_TAG ('g', 'a', 's', 'p'),
+ HB_OT_TAG_GDEF,
+ HB_OT_TAG_glyf,
+ HB_OT_TAG_GPOS,
+ HB_OT_TAG_GSUB,
+ HB_OT_TAG_gvar,
+ HB_OT_TAG_hdmx,
+ HB_OT_TAG_head,
+ HB_OT_TAG_hhea,
+ HB_OT_TAG_hmtx,
+ HB_OT_TAG_HVAR,
+ HB_OT_TAG_JSTF,
+ HB_TAG ('k', 'e', 'r', 'n'),
+ HB_OT_TAG_loca,
+ HB_TAG ('L', 'T', 'S', 'H'),
+ HB_OT_TAG_MATH,
+ HB_OT_TAG_maxp,
+ HB_TAG ('M', 'E', 'R', 'G'),
+ HB_TAG ('m', 'e', 't', 'a'),
+ HB_TAG ('M', 'V', 'A', 'R'),
+ HB_TAG ('P', 'C', 'L', 'T'),
+ HB_OT_TAG_post,
+ HB_TAG ('p', 'r', 'e', 'p'),
+ HB_OT_TAG_sbix,
+ HB_TAG ('S', 'T', 'A', 'T'),
+ HB_TAG ('S', 'V', 'G', ' '),
+ HB_TAG ('V', 'D', 'M', 'X'),
+ HB_OT_TAG_vhea,
+ HB_OT_TAG_vmtx,
+ HB_OT_TAG_VORG,
+ HB_OT_TAG_VVAR,
+ HB_OT_TAG_name,
+ HB_OT_TAG_OS2
+};
+
+static bool _table_is_empty (const hb_face_t *face, hb_tag_t tag)
+{
+ hb_blob_t* blob = hb_face_reference_table (face, tag);
+ bool result = (blob == hb_blob_get_empty ());
+ hb_blob_destroy (blob);
+ return result;
+}
+
+static unsigned int
+_get_table_tags (const hb_subset_plan_t* plan,
+ unsigned int start_offset,
+ unsigned int *table_count, /* IN/OUT */
+ hb_tag_t *table_tags /* OUT */)
+{
+ unsigned num_tables = hb_face_get_table_tags (plan->source, 0, nullptr, nullptr);
+ if (num_tables)
+ return hb_face_get_table_tags (plan->source, start_offset, table_count, table_tags);
+
+ // If face has 0 tables associated with it, assume that it was built from
+ // hb_face_create_tables and thus is unable to list its tables. Fallback to
+ // checking each table type we can handle for existence instead.
+ auto it =
+ hb_concat (
+ + hb_array (known_tables)
+ | hb_filter ([&] (hb_tag_t tag) {
+ return !_table_is_empty (plan->source, tag) && !plan->no_subset_tables->has (tag);
+ })
+ | hb_map ([] (hb_tag_t tag) -> hb_tag_t { return tag; }),
+
+ plan->no_subset_tables->iter ()
+ | hb_filter([&] (hb_tag_t tag) {
+ return !_table_is_empty (plan->source, tag);
+ }));
+
+ it += start_offset;
+
+ unsigned num_written = 0;
+ while (bool (it) && num_written < *table_count)
+ table_tags[num_written++] = *it++;
+
+ *table_count = num_written;
+ return num_written;
+}
+
+
static unsigned
_plan_estimate_subset_table_size (hb_subset_plan_t *plan,
unsigned table_len,
@@ -224,9 +326,17 @@ _subset (hb_subset_plan_t *plan, hb_vector_t<char> &buf)
static bool
_is_table_present (hb_face_t *source, hb_tag_t tag)
{
+
+ if (!hb_face_get_table_tags (source, 0, nullptr, nullptr)) {
+ // If face has 0 tables associated with it, assume that it was built from
+ // hb_face_create_tables and thus is unable to list its tables. Fallback to
+ // checking if the blob associated with tag is empty.
+ return !_table_is_empty (source, tag);
+ }
+
hb_tag_t table_tags[32];
unsigned offset = 0, num_tables = ARRAY_LENGTH (table_tags);
- while ((hb_face_get_table_tags (source, offset, &num_tables, table_tags), num_tables))
+ while (((void) hb_face_get_table_tags (source, offset, &num_tables, table_tags), num_tables))
{
for (unsigned i = 0; i < num_tables; ++i)
if (table_tags[i] == tag)
@@ -388,7 +498,8 @@ hb_subset_plan_execute_or_fail (hb_subset_plan_t *plan)
unsigned offset = 0, num_tables = ARRAY_LENGTH (table_tags);
hb_vector_t<char> buf;
buf.alloc (4096 - 16);
- while ((hb_face_get_table_tags (plan->source, offset, &num_tables, table_tags), num_tables))
+
+ while (((void) _get_table_tags (plan, offset, &num_tables, table_tags), num_tables))
{
for (unsigned i = 0; i < num_tables; ++i)
{
@@ -400,7 +511,7 @@ hb_subset_plan_execute_or_fail (hb_subset_plan_t *plan)
}
offset += num_tables;
}
-end:
+end:
return success ? hb_face_reference (plan->dest) : nullptr;
}