/gfx/ots/src/gpos.cc
C++ | 809 lines | 623 code | 88 blank | 98 comment | 157 complexity | 4ebb741fae092cc5d3b8771f599657c7 MD5 | raw file
Possible License(s): MPL-2.0-no-copyleft-exception, LGPL-3.0, AGPL-1.0, LGPL-2.1, BSD-3-Clause, GPL-2.0, JSON, Apache-2.0, 0BSD
- // Copyright (c) 2011 The Chromium Authors. All rights reserved.
- // Use of this source code is governed by a BSD-style license that can be
- // found in the LICENSE file.
- #include "gpos.h"
- #include <limits>
- #include <vector>
- #include "gdef.h"
- #include "gsub.h"
- #include "layout.h"
- #include "maxp.h"
- // GPOS - The Glyph Positioning Table
- // http://www.microsoft.com/typography/otspec/gpos.htm
- namespace {
- enum GPOS_TYPE {
- GPOS_TYPE_SINGLE_ADJUSTMENT = 1,
- GPOS_TYPE_PAIR_ADJUSTMENT = 2,
- GPOS_TYPE_CURSIVE_ATTACHMENT = 3,
- GPOS_TYPE_MARK_TO_BASE_ATTACHMENT = 4,
- GPOS_TYPE_MARK_TO_LIGATURE_ATTACHMENT = 5,
- GPOS_TYPE_MARK_TO_MARK_ATTACHMENT = 6,
- GPOS_TYPE_CONTEXT_POSITIONING = 7,
- GPOS_TYPE_CHAINED_CONTEXT_POSITIONING = 8,
- GPOS_TYPE_EXTENSION_POSITIONING = 9,
- GPOS_TYPE_RESERVED = 10
- };
- // The size of gpos header.
- const unsigned kGposHeaderSize = 10;
- // The maximum format number for anchor tables.
- const uint16_t kMaxAnchorFormat = 3;
- // The maximum number of class value.
- const uint16_t kMaxClassDefValue = 0xFFFF;
- // Lookup type parsers.
- bool ParseSingleAdjustment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParsePairAdjustment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParseCursiveAttachment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParseMarkToBaseAttachment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParseMarkToLigatureAttachment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParseMarkToMarkAttachment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParseContextPositioning(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParseChainedContextPositioning(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- bool ParseExtensionPositioning(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length);
- const ots::LookupSubtableParser::TypeParser kGposTypeParsers[] = {
- {GPOS_TYPE_SINGLE_ADJUSTMENT, ParseSingleAdjustment},
- {GPOS_TYPE_PAIR_ADJUSTMENT, ParsePairAdjustment},
- {GPOS_TYPE_CURSIVE_ATTACHMENT, ParseCursiveAttachment},
- {GPOS_TYPE_MARK_TO_BASE_ATTACHMENT, ParseMarkToBaseAttachment},
- {GPOS_TYPE_MARK_TO_LIGATURE_ATTACHMENT, ParseMarkToLigatureAttachment},
- {GPOS_TYPE_MARK_TO_MARK_ATTACHMENT, ParseMarkToMarkAttachment},
- {GPOS_TYPE_CONTEXT_POSITIONING, ParseContextPositioning},
- {GPOS_TYPE_CHAINED_CONTEXT_POSITIONING, ParseChainedContextPositioning},
- {GPOS_TYPE_EXTENSION_POSITIONING, ParseExtensionPositioning}
- };
- const ots::LookupSubtableParser kGposLookupSubtableParser = {
- GPOS_TYPE_RESERVED, GPOS_TYPE_EXTENSION_POSITIONING, kGposTypeParsers
- };
- // Shared Tables: ValueRecord, Anchor Table, and MarkArray
- bool ParseValueRecord(ots::Buffer* subtable, const uint8_t *data,
- const size_t length, const uint16_t value_format) {
- // Check existence of adjustment fields.
- for (unsigned i = 0; i < 4; ++i) {
- if ((value_format >> i) & 0x1) {
- // Just read the field since these fileds could take an arbitrary values.
- if (!subtable->Skip(2)) {
- return OTS_FAILURE();
- }
- }
- }
- // Check existence of offsets to device table.
- for (unsigned i = 0; i < 4; ++i) {
- if ((value_format >> (i + 4)) & 0x1) {
- uint16_t offset = 0;
- if (!subtable->ReadU16(&offset)) {
- return OTS_FAILURE();
- }
- if (offset) {
- // TODO(bashi): Is it possible that device tables locate before
- // this record? No fonts contain such offset AKAIF.
- if (offset >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseDeviceTable(data + offset, length - offset)) {
- return OTS_FAILURE();
- }
- }
- }
- }
- return true;
- }
- bool ParseAnchorTable(const uint8_t *data, const size_t length) {
- ots::Buffer subtable(data, length);
- uint16_t format = 0;
- // Read format and skip 2 2-byte fields that could be arbitrary values.
- if (!subtable.ReadU16(&format) ||
- !subtable.Skip(4)) {
- return OTS_FAILURE();
- }
- if (format == 0 || format > kMaxAnchorFormat) {
- return OTS_FAILURE();
- }
- // Format 2 and 3 has additional fields.
- if (format == 2) {
- // Format 2 provides an index to a glyph contour point, which will take
- // arbitrary value.
- uint16_t anchor_point = 0;
- if (!subtable.ReadU16(&anchor_point)) {
- return OTS_FAILURE();
- }
- } else if (format == 3) {
- uint16_t offset_x_device = 0;
- uint16_t offset_y_device = 0;
- if (!subtable.ReadU16(&offset_x_device) ||
- !subtable.ReadU16(&offset_y_device)) {
- return OTS_FAILURE();
- }
- const unsigned format_end = static_cast<unsigned>(10);
- if (offset_x_device) {
- if (offset_x_device < format_end || offset_x_device >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseDeviceTable(data + offset_x_device,
- length - offset_x_device)) {
- return OTS_FAILURE();
- }
- }
- if (offset_y_device) {
- if (offset_y_device < format_end || offset_y_device >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseDeviceTable(data + offset_y_device,
- length - offset_y_device)) {
- return OTS_FAILURE();
- }
- }
- }
- return true;
- }
- bool ParseMarkArrayTable(const uint8_t *data, const size_t length,
- const uint16_t class_count) {
- ots::Buffer subtable(data, length);
- uint16_t mark_count = 0;
- if (!subtable.ReadU16(&mark_count)) {
- return OTS_FAILURE();
- }
- // MarkRecord consists of 4-bytes.
- const unsigned mark_records_end = 4 * static_cast<unsigned>(mark_count) + 2;
- if (mark_records_end > std::numeric_limits<uint16_t>::max()) {
- return OTS_FAILURE();
- }
- for (unsigned i = 0; i < mark_count; ++i) {
- uint16_t class_value = 0;
- uint16_t offset_mark_anchor = 0;
- if (!subtable.ReadU16(&class_value) ||
- !subtable.ReadU16(&offset_mark_anchor)) {
- return OTS_FAILURE();
- }
- // |class_value| may take arbitrary values including 0 here so we don't
- // check the value.
- if (offset_mark_anchor < mark_records_end ||
- offset_mark_anchor >= length) {
- return OTS_FAILURE();
- }
- if (!ParseAnchorTable(data + offset_mark_anchor,
- length - offset_mark_anchor)) {
- return OTS_FAILURE();
- }
- }
- return true;
- }
- // Lookup Type 1:
- // Single Adjustment Positioning Subtable
- bool ParseSingleAdjustment(const ots::OpenTypeFile *file, const uint8_t *data,
- const size_t length) {
- ots::Buffer subtable(data, length);
- uint16_t format = 0;
- uint16_t offset_coverage = 0;
- uint16_t value_format = 0;
- if (!subtable.ReadU16(&format) ||
- !subtable.ReadU16(&offset_coverage) ||
- !subtable.ReadU16(&value_format)) {
- return OTS_FAILURE();
- }
- if (format == 1) {
- // Format 1 exactly one value record.
- if (!ParseValueRecord(&subtable, data, length, value_format)) {
- return OTS_FAILURE();
- }
- } else if (format == 2) {
- uint16_t value_count = 0;
- if (!subtable.ReadU16(&value_count)) {
- return OTS_FAILURE();
- }
- for (unsigned i = 0; i < value_count; ++i) {
- if (!ParseValueRecord(&subtable, data, length, value_format)) {
- return OTS_FAILURE();
- }
- }
- } else {
- return OTS_FAILURE();
- }
- if (offset_coverage < subtable.offset() || offset_coverage >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseCoverageTable(data + offset_coverage,
- length - offset_coverage,
- file->maxp->num_glyphs)) {
- return OTS_FAILURE();
- }
- return true;
- }
- bool ParsePairSetTable(const uint8_t *data, const size_t length,
- const uint16_t value_format1,
- const uint16_t value_format2,
- const uint16_t num_glyphs) {
- ots::Buffer subtable(data, length);
- uint16_t value_count = 0;
- if (!subtable.ReadU16(&value_count)) {
- return OTS_FAILURE();
- }
- for (unsigned i = 0; i < value_count; ++i) {
- // Check pair value record.
- uint16_t glyph_id = 0;
- if (!subtable.ReadU16(&glyph_id)) {
- return OTS_FAILURE();
- }
- if (glyph_id >= num_glyphs) {
- return OTS_FAILURE();
- }
- if (!ParseValueRecord(&subtable, data, length, value_format1)) {
- return OTS_FAILURE();
- }
- if (!ParseValueRecord(&subtable, data, length, value_format2)) {
- return OTS_FAILURE();
- }
- }
- return true;
- }
- bool ParsePairPosFormat1(const uint8_t *data, const size_t length,
- const uint16_t value_format1,
- const uint16_t value_format2,
- const uint16_t num_glyphs) {
- ots::Buffer subtable(data, length);
- // Skip 8 bytes that are already read before.
- if (!subtable.Skip(8)) {
- return OTS_FAILURE();
- }
- uint16_t pair_set_count = 0;
- if (!subtable.ReadU16(&pair_set_count)) {
- return OTS_FAILURE();
- }
- const unsigned pair_pos_end = 2 * static_cast<unsigned>(pair_set_count) + 10;
- if (pair_pos_end > std::numeric_limits<uint16_t>::max()) {
- return OTS_FAILURE();
- }
- for (unsigned i = 0; i < pair_set_count; ++i) {
- uint16_t pair_set_offset = 0;
- if (!subtable.ReadU16(&pair_set_offset)) {
- return OTS_FAILURE();
- }
- if (pair_set_offset < pair_pos_end || pair_set_offset >= length) {
- return OTS_FAILURE();
- }
- // Check pair set tables
- if (!ParsePairSetTable(data + pair_set_offset, length - pair_set_offset,
- value_format1, value_format2,
- num_glyphs)) {
- return OTS_FAILURE();
- }
- }
- return true;
- }
- bool ParsePairPosFormat2(const uint8_t *data, const size_t length,
- const uint16_t value_format1,
- const uint16_t value_format2,
- const uint16_t num_glyphs) {
- ots::Buffer subtable(data, length);
- // Skip 8 bytes that are already read before.
- if (!subtable.Skip(8)) {
- return OTS_FAILURE();
- }
- uint16_t offset_class_def1 = 0;
- uint16_t offset_class_def2 = 0;
- uint16_t class1_count = 0;
- uint16_t class2_count = 0;
- if (!subtable.ReadU16(&offset_class_def1) ||
- !subtable.ReadU16(&offset_class_def2) ||
- !subtable.ReadU16(&class1_count) ||
- !subtable.ReadU16(&class2_count)) {
- return OTS_FAILURE();
- }
- // Check class 1 records.
- for (unsigned i = 0; i < class1_count; ++i) {
- // Check class 2 records.
- for (unsigned j = 0; j < class2_count; ++j) {
- if (value_format1 && !ParseValueRecord(&subtable, data, length,
- value_format1)) {
- return OTS_FAILURE();
- }
- if (value_format2 && !ParseValueRecord(&subtable, data, length,
- value_format2)) {
- return OTS_FAILURE();
- }
- }
- }
- // Check class definition tables.
- if (offset_class_def1 < subtable.offset() || offset_class_def1 >= length ||
- offset_class_def2 < subtable.offset() || offset_class_def2 >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseClassDefTable(data + offset_class_def1,
- length - offset_class_def1,
- num_glyphs, kMaxClassDefValue)) {
- return OTS_FAILURE();
- }
- if (!ots::ParseClassDefTable(data + offset_class_def2,
- length - offset_class_def2,
- num_glyphs, kMaxClassDefValue)) {
- return OTS_FAILURE();
- }
- return true;
- }
- // Lookup Type 2:
- // Pair Adjustment Positioning Subtable
- bool ParsePairAdjustment(const ots::OpenTypeFile *file, const uint8_t *data,
- const size_t length) {
- ots::Buffer subtable(data, length);
- uint16_t format = 0;
- uint16_t offset_coverage = 0;
- uint16_t value_format1 = 0;
- uint16_t value_format2 = 0;
- if (!subtable.ReadU16(&format) ||
- !subtable.ReadU16(&offset_coverage) ||
- !subtable.ReadU16(&value_format1) ||
- !subtable.ReadU16(&value_format2)) {
- return OTS_FAILURE();
- }
- if (format == 1) {
- if (!ParsePairPosFormat1(data, length, value_format1, value_format2,
- file->maxp->num_glyphs)) {
- return OTS_FAILURE();
- }
- } else if (format == 2) {
- if (!ParsePairPosFormat2(data, length, value_format1, value_format2,
- file->maxp->num_glyphs)) {
- return OTS_FAILURE();
- }
- } else {
- return OTS_FAILURE();
- }
- if (offset_coverage < subtable.offset() || offset_coverage >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseCoverageTable(data + offset_coverage,
- length - offset_coverage,
- file->maxp->num_glyphs)) {
- return OTS_FAILURE();
- }
- return true;
- }
- // Lookup Type 3
- // Cursive Attachment Positioning Subtable
- bool ParseCursiveAttachment(const ots::OpenTypeFile *file, const uint8_t *data,
- const size_t length) {
- ots::Buffer subtable(data, length);
- uint16_t format = 0;
- uint16_t offset_coverage = 0;
- uint16_t entry_exit_count = 0;
- if (!subtable.ReadU16(&format) ||
- !subtable.ReadU16(&offset_coverage) ||
- !subtable.ReadU16(&entry_exit_count)) {
- return OTS_FAILURE();
- }
- if (format != 1) {
- return OTS_FAILURE();
- }
- // Check entry exit records.
- const unsigned entry_exit_records_end =
- 2 * static_cast<unsigned>(entry_exit_count) + 6;
- if (entry_exit_records_end > std::numeric_limits<uint16_t>::max()) {
- return OTS_FAILURE();
- }
- for (unsigned i = 0; i < entry_exit_count; ++i) {
- uint16_t offset_entry_anchor = 0;
- uint16_t offset_exit_anchor = 0;
- if (!subtable.ReadU16(&offset_entry_anchor) ||
- !subtable.ReadU16(&offset_exit_anchor)) {
- return OTS_FAILURE();
- }
- // These offsets could be NULL.
- if (offset_entry_anchor) {
- if (offset_entry_anchor < entry_exit_records_end ||
- offset_entry_anchor >= length) {
- return OTS_FAILURE();
- }
- if (!ParseAnchorTable(data + offset_entry_anchor,
- length - offset_entry_anchor)) {
- return OTS_FAILURE();
- }
- }
- if (offset_exit_anchor) {
- if (offset_exit_anchor < entry_exit_records_end ||
- offset_exit_anchor >= length) {
- return OTS_FAILURE();
- }
- if (!ParseAnchorTable(data + offset_exit_anchor,
- length - offset_exit_anchor)) {
- return OTS_FAILURE();
- }
- }
- }
- if (offset_coverage < subtable.offset() || offset_coverage >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseCoverageTable(data + offset_coverage,
- length - offset_coverage,
- file->maxp->num_glyphs)) {
- return OTS_FAILURE();
- }
- return true;
- }
- bool ParseAnchorArrayTable(const uint8_t *data, const size_t length,
- const uint16_t class_count) {
- ots::Buffer subtable(data, length);
- uint16_t record_count = 0;
- if (!subtable.ReadU16(&record_count)) {
- return OTS_FAILURE();
- }
- const unsigned anchor_array_end = 2 * static_cast<unsigned>(record_count) *
- static_cast<unsigned>(class_count) + 2;
- if (anchor_array_end > std::numeric_limits<uint16_t>::max()) {
- return OTS_FAILURE();
- }
- for (unsigned i = 0; i < record_count; ++i) {
- for (unsigned j = 0; j < class_count; ++j) {
- uint16_t offset_record = 0;
- if (!subtable.ReadU16(&offset_record)) {
- return OTS_FAILURE();
- }
- // |offset_record| could be NULL.
- if (offset_record) {
- if (offset_record < anchor_array_end || offset_record >= length) {
- return OTS_FAILURE();
- }
- if (!ParseAnchorTable(data + offset_record,
- length - offset_record)) {
- return OTS_FAILURE();
- }
- }
- }
- }
- return true;
- }
- bool ParseLigatureArrayTable(const uint8_t *data, const size_t length,
- const uint16_t class_count) {
- ots::Buffer subtable(data, length);
- uint16_t ligature_count = 0;
- if (!subtable.ReadU16(&ligature_count)) {
- return OTS_FAILURE();
- }
- for (unsigned i = 0; i < ligature_count; ++i) {
- uint16_t offset_ligature_attach = 0;
- if (!subtable.ReadU16(&offset_ligature_attach)) {
- return OTS_FAILURE();
- }
- if (offset_ligature_attach < 2 || offset_ligature_attach >= length) {
- return OTS_FAILURE();
- }
- if (!ParseAnchorArrayTable(data + offset_ligature_attach,
- length - offset_ligature_attach, class_count)) {
- return OTS_FAILURE();
- }
- }
- return true;
- }
- // Common parser for Lookup Type 4, 5 and 6.
- bool ParseMarkToAttachmentSubtables(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length,
- const GPOS_TYPE type) {
- ots::Buffer subtable(data, length);
- uint16_t format = 0;
- uint16_t offset_coverage1 = 0;
- uint16_t offset_coverage2 = 0;
- uint16_t class_count = 0;
- uint16_t offset_mark_array = 0;
- uint16_t offset_type_specific_array = 0;
- if (!subtable.ReadU16(&format) ||
- !subtable.ReadU16(&offset_coverage1) ||
- !subtable.ReadU16(&offset_coverage2) ||
- !subtable.ReadU16(&class_count) ||
- !subtable.ReadU16(&offset_mark_array) ||
- !subtable.ReadU16(&offset_type_specific_array)) {
- return OTS_FAILURE();
- }
- if (format != 1) {
- return OTS_FAILURE();
- }
- const unsigned header_end = static_cast<unsigned>(subtable.offset());
- if (header_end > std::numeric_limits<uint16_t>::max()) {
- return OTS_FAILURE();
- }
- if (offset_coverage1 < header_end || offset_coverage1 >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseCoverageTable(data + offset_coverage1,
- length - offset_coverage1,
- file->maxp->num_glyphs)) {
- return OTS_FAILURE();
- }
- if (offset_coverage2 < header_end || offset_coverage2 >= length) {
- return OTS_FAILURE();
- }
- if (!ots::ParseCoverageTable(data + offset_coverage2,
- length - offset_coverage2,
- file->maxp->num_glyphs)) {
- return OTS_FAILURE();
- }
- if (offset_mark_array < header_end || offset_mark_array >= length) {
- return OTS_FAILURE();
- }
- if (!ParseMarkArrayTable(data + offset_mark_array,
- length - offset_mark_array, class_count)) {
- return OTS_FAILURE();
- }
- if (offset_type_specific_array < header_end ||
- offset_type_specific_array >= length) {
- return OTS_FAILURE();
- }
- if (type == GPOS_TYPE_MARK_TO_BASE_ATTACHMENT ||
- type == GPOS_TYPE_MARK_TO_MARK_ATTACHMENT) {
- if (!ParseAnchorArrayTable(data + offset_type_specific_array,
- length - offset_type_specific_array,
- class_count)) {
- return OTS_FAILURE();
- }
- } else if (type == GPOS_TYPE_MARK_TO_LIGATURE_ATTACHMENT) {
- if (!ParseLigatureArrayTable(data + offset_type_specific_array,
- length - offset_type_specific_array,
- class_count)) {
- return OTS_FAILURE();
- }
- } else {
- return OTS_FAILURE();
- }
- return true;
- }
- // Lookup Type 4:
- // MarkToBase Attachment Positioning Subtable
- bool ParseMarkToBaseAttachment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length) {
- return ParseMarkToAttachmentSubtables(file, data, length,
- GPOS_TYPE_MARK_TO_BASE_ATTACHMENT);
- }
- // Lookup Type 5:
- // MarkToLigature Attachment Positioning Subtable
- bool ParseMarkToLigatureAttachment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length) {
- return ParseMarkToAttachmentSubtables(file, data, length,
- GPOS_TYPE_MARK_TO_LIGATURE_ATTACHMENT);
- }
- // Lookup Type 6:
- // MarkToMark Attachment Positioning Subtable
- bool ParseMarkToMarkAttachment(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length) {
- return ParseMarkToAttachmentSubtables(file, data, length,
- GPOS_TYPE_MARK_TO_MARK_ATTACHMENT);
- }
- // Lookup Type 7:
- // Contextual Positioning Subtables
- bool ParseContextPositioning(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length) {
- return ots::ParseContextSubtable(data, length, file->maxp->num_glyphs,
- file->gpos->num_lookups);
- }
- // Lookup Type 8:
- // Chaining Contexual Positioning Subtable
- bool ParseChainedContextPositioning(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length) {
- return ots::ParseChainingContextSubtable(data, length,
- file->maxp->num_glyphs,
- file->gpos->num_lookups);
- }
- // Lookup Type 9:
- // Extension Positioning
- bool ParseExtensionPositioning(const ots::OpenTypeFile *file,
- const uint8_t *data, const size_t length) {
- return ots::ParseExtensionSubtable(file, data, length,
- &kGposLookupSubtableParser);
- }
- } // namespace
- #define DROP_THIS_TABLE \
- do { file->gpos->data = 0; file->gpos->length = 0; } while (0)
- namespace ots {
- // As far as I checked, following fonts contain invalid GPOS table and
- // OTS will drop their GPOS table.
- //
- // # invalid delta format in device table
- // samanata.ttf
- //
- // # bad size range in device table
- // Sarai_07.ttf
- //
- // # bad offset to PairSetTable
- // chandas1-2.ttf
- //
- // # bad offset to FeatureTable
- // glrso12.ttf
- // gllr12.ttf
- // glbo12.ttf
- // glb12.ttf
- // glro12.ttf
- // glbso12.ttf
- // glrc12.ttf
- // glrsc12.ttf
- // glbs12.ttf
- // glrs12.ttf
- // glr12.ttf
- //
- // # ScriptRecords aren't sorted by tag
- // Garogier_unhinted.otf
- //
- // # bad start coverage index in CoverageFormat2
- // AndBasR.ttf
- // CharisSILB.ttf
- // CharisSILBI.ttf
- // CharisSILI.ttf
- // CharisSILR.ttf
- // DoulosSILR.ttf
- // GenBasBI.ttf
- // GenBasI.ttf
- // GenBkBasI.ttf
- // GenBkBasB.ttf
- // GenBkBasR.ttf
- // Padauk-Bold.ttf
- // Padauk.ttf
- //
- // # Contour point indexes aren't sorted
- // Arial Unicode.ttf
- bool ots_gpos_parse(OpenTypeFile *file, const uint8_t *data, size_t length) {
- // Parsing GPOS table requires num_glyphs which is contained in maxp table.
- if (!file->maxp) {
- return OTS_FAILURE();
- }
- Buffer table(data, length);
- OpenTypeGPOS *gpos = new OpenTypeGPOS;
- file->gpos = gpos;
- uint32_t version = 0;
- uint16_t offset_script_list = 0;
- uint16_t offset_feature_list = 0;
- uint16_t offset_lookup_list = 0;
- if (!table.ReadU32(&version) ||
- !table.ReadU16(&offset_script_list) ||
- !table.ReadU16(&offset_feature_list) ||
- !table.ReadU16(&offset_lookup_list)) {
- return OTS_FAILURE();
- }
- if (version != 0x00010000) {
- OTS_WARNING("bad GPOS version");
- DROP_THIS_TABLE;
- return true;
- }
- if ((offset_script_list < kGposHeaderSize ||
- offset_script_list >= length) ||
- (offset_feature_list < kGposHeaderSize ||
- offset_feature_list >= length) ||
- (offset_lookup_list < kGposHeaderSize ||
- offset_lookup_list >= length)) {
- OTS_WARNING("bad offset in GPOS header");
- DROP_THIS_TABLE;
- return true;
- }
- if (!ParseLookupListTable(file, data + offset_lookup_list,
- length - offset_lookup_list,
- &kGposLookupSubtableParser,
- &gpos->num_lookups)) {
- OTS_WARNING("faild to parse lookup list table");
- DROP_THIS_TABLE;
- return true;
- }
- uint16_t num_features = 0;
- if (!ParseFeatureListTable(data + offset_feature_list,
- length - offset_feature_list, gpos->num_lookups,
- &num_features)) {
- OTS_WARNING("faild to parse feature list table");
- DROP_THIS_TABLE;
- return true;
- }
- if (!ParseScriptListTable(data + offset_script_list,
- length - offset_script_list, num_features)) {
- OTS_WARNING("faild to parse script list table");
- DROP_THIS_TABLE;
- return true;
- }
- gpos->data = data;
- gpos->length = length;
- return true;
- }
- bool ots_gpos_should_serialise(OpenTypeFile *file) {
- const bool needed_tables_dropped =
- (file->gdef && file->gdef->data == NULL) ||
- (file->gsub && file->gsub->data == NULL);
- return file->gpos != NULL && file->gpos->data != NULL &&
- !needed_tables_dropped;
- }
- bool ots_gpos_serialise(OTSStream *out, OpenTypeFile *file) {
- if (!out->Write(file->gpos->data, file->gpos->length)) {
- return OTS_FAILURE();
- }
- return true;
- }
- void ots_gpos_free(OpenTypeFile *file) {
- delete file->gpos;
- }
- } // namespace ots