| /* Copyright 2013 Google Inc. All Rights Reserved. |
| |
| Distributed under MIT license. |
| See file LICENSE for detail or copy at https://opensource.org/licenses/MIT |
| */ |
| |
| /* Font management utilities */ |
| |
| #include "./font.h" |
| |
| #include <algorithm> |
| |
| #if !defined(STARBOARD) |
| #include <string.h> |
| #else |
| #include "starboard/client_porting/poem/string_poem.h" |
| #endif |
| |
| #include "./buffer.h" |
| #include "./port.h" |
| #include "./store_bytes.h" |
| #include "./table_tags.h" |
| #include "./woff2_common.h" |
| |
| namespace woff2 { |
| |
| Font::Table* Font::FindTable(uint32_t tag) { |
| std::map<uint32_t, Font::Table>::iterator it = tables.find(tag); |
| return it == tables.end() ? 0 : &it->second; |
| } |
| |
| const Font::Table* Font::FindTable(uint32_t tag) const { |
| std::map<uint32_t, Font::Table>::const_iterator it = tables.find(tag); |
| return it == tables.end() ? 0 : &it->second; |
| } |
| |
| std::vector<uint32_t> Font::OutputOrderedTags() const { |
| std::vector<uint32_t> output_order; |
| |
| for (const auto& i : tables) { |
| const Font::Table& table = i.second; |
| // This is a transformed table, we will write it together with the |
| // original version. |
| if (table.tag & 0x80808080) { |
| continue; |
| } |
| output_order.push_back(table.tag); |
| } |
| |
| // Alphabetize then put loca immediately after glyf |
| auto glyf_loc = std::find(output_order.begin(), output_order.end(), |
| kGlyfTableTag); |
| auto loca_loc = std::find(output_order.begin(), output_order.end(), |
| kLocaTableTag); |
| if (glyf_loc != output_order.end() && loca_loc != output_order.end()) { |
| output_order.erase(loca_loc); |
| output_order.insert(std::find(output_order.begin(), output_order.end(), |
| kGlyfTableTag) + 1, kLocaTableTag); |
| } |
| |
| return output_order; |
| } |
| |
| bool ReadTrueTypeFont(Buffer* file, const uint8_t* data, size_t len, |
| Font* font) { |
| // We don't care about the search_range, entry_selector and range_shift |
| // fields, they will always be computed upon writing the font. |
| if (!file->ReadU16(&font->num_tables) || |
| !file->Skip(6)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| |
| std::map<uint32_t, uint32_t> intervals; |
| for (uint16_t i = 0; i < font->num_tables; ++i) { |
| Font::Table table; |
| table.flag_byte = 0; |
| table.reuse_of = NULL; |
| if (!file->ReadU32(&table.tag) || |
| !file->ReadU32(&table.checksum) || |
| !file->ReadU32(&table.offset) || |
| !file->ReadU32(&table.length)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| if ((table.offset & 3) != 0 || |
| table.length > len || |
| len - table.length < table.offset) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| intervals[table.offset] = table.length; |
| table.data = data + table.offset; |
| if (font->tables.find(table.tag) != font->tables.end()) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| font->tables[table.tag] = table; |
| } |
| |
| // Check that tables are non-overlapping. |
| uint32_t last_offset = 12UL + 16UL * font->num_tables; |
| for (const auto& i : intervals) { |
| if (i.first < last_offset || i.first + i.second < i.first) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| last_offset = i.first + i.second; |
| } |
| |
| // Sanity check key tables |
| const Font::Table* head_table = font->FindTable(kHeadTableTag); |
| if (head_table != NULL && head_table->length < 52) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| |
| return true; |
| } |
| |
| bool ReadCollectionFont(Buffer* file, const uint8_t* data, size_t len, |
| Font* font, |
| std::map<uint32_t, Font::Table*>* all_tables) { |
| if (!file->ReadU32(&font->flavor)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| if (!ReadTrueTypeFont(file, data, len, font)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| |
| for (auto& entry : font->tables) { |
| Font::Table& table = entry.second; |
| |
| if (all_tables->find(table.offset) == all_tables->end()) { |
| (*all_tables)[table.offset] = font->FindTable(table.tag); |
| } else { |
| table.reuse_of = (*all_tables)[table.offset]; |
| if (table.tag != table.reuse_of->tag) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| } |
| |
| } |
| return true; |
| } |
| |
| bool ReadTrueTypeCollection(Buffer* file, const uint8_t* data, size_t len, |
| FontCollection* font_collection) { |
| uint32_t num_fonts; |
| |
| if (!file->ReadU32(&font_collection->header_version) || |
| !file->ReadU32(&num_fonts)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| |
| std::vector<uint32_t> offsets; |
| for (size_t i = 0; i < num_fonts; i++) { |
| uint32_t offset; |
| if (!file->ReadU32(&offset)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| offsets.push_back(offset); |
| } |
| |
| font_collection->fonts.resize(offsets.size()); |
| std::vector<Font>::iterator font_it = font_collection->fonts.begin(); |
| |
| std::map<uint32_t, Font::Table*> all_tables; |
| for (const auto offset : offsets) { |
| file->set_offset(offset); |
| Font& font = *font_it++; |
| if (!ReadCollectionFont(file, data, len, &font, &all_tables)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| } |
| |
| return true; |
| } |
| |
| bool ReadFont(const uint8_t* data, size_t len, Font* font) { |
| Buffer file(data, len); |
| |
| if (!file.ReadU32(&font->flavor)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| |
| if (font->flavor == kTtcFontFlavor) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| return ReadTrueTypeFont(&file, data, len, font); |
| } |
| |
| bool ReadFontCollection(const uint8_t* data, size_t len, |
| FontCollection* font_collection) { |
| Buffer file(data, len); |
| |
| if (!file.ReadU32(&font_collection->flavor)) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| |
| if (font_collection->flavor != kTtcFontFlavor) { |
| font_collection->fonts.resize(1); |
| Font& font = font_collection->fonts[0]; |
| font.flavor = font_collection->flavor; |
| return ReadTrueTypeFont(&file, data, len, &font); |
| } |
| return ReadTrueTypeCollection(&file, data, len, font_collection); |
| } |
| |
| size_t FontFileSize(const Font& font) { |
| size_t max_offset = 12ULL + 16ULL * font.num_tables; |
| for (const auto& i : font.tables) { |
| const Font::Table& table = i.second; |
| size_t padding_size = (4 - (table.length & 3)) & 3; |
| size_t end_offset = (padding_size + table.offset) + table.length; |
| max_offset = std::max(max_offset, end_offset); |
| } |
| return max_offset; |
| } |
| |
| size_t FontCollectionFileSize(const FontCollection& font_collection) { |
| size_t max_offset = 0; |
| for (auto& font : font_collection.fonts) { |
| // font file size actually just finds max offset |
| max_offset = std::max(max_offset, FontFileSize(font)); |
| } |
| return max_offset; |
| } |
| |
| bool WriteFont(const Font& font, uint8_t* dst, size_t dst_size) { |
| size_t offset = 0; |
| return WriteFont(font, &offset, dst, dst_size); |
| } |
| |
| bool WriteTableRecord(const Font::Table* table, size_t* offset, uint8_t* dst, |
| size_t dst_size) { |
| if (dst_size < *offset + kSfntEntrySize) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| if (table->IsReused()) { |
| table = table->reuse_of; |
| } |
| StoreU32(table->tag, offset, dst); |
| StoreU32(table->checksum, offset, dst); |
| StoreU32(table->offset, offset, dst); |
| StoreU32(table->length, offset, dst); |
| return true; |
| } |
| |
| bool WriteTable(const Font::Table& table, size_t* offset, uint8_t* dst, |
| size_t dst_size) { |
| if (!WriteTableRecord(&table, offset, dst, dst_size)) { |
| return false; |
| } |
| |
| // Write the actual table data if it's the first time we've seen it |
| if (!table.IsReused()) { |
| if (table.offset + table.length < table.offset || |
| dst_size < table.offset + table.length) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| memcpy(dst + table.offset, table.data, table.length); |
| size_t padding_size = (4 - (table.length & 3)) & 3; |
| if (table.offset + table.length + padding_size < padding_size || |
| dst_size < table.offset + table.length + padding_size) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| memset(dst + table.offset + table.length, 0, padding_size); |
| } |
| return true; |
| } |
| |
| bool WriteFont(const Font& font, size_t* offset, uint8_t* dst, |
| size_t dst_size) { |
| if (dst_size < 12ULL + 16ULL * font.num_tables) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| StoreU32(font.flavor, offset, dst); |
| Store16(font.num_tables, offset, dst); |
| uint16_t max_pow2 = font.num_tables ? Log2Floor(font.num_tables) : 0; |
| uint16_t search_range = max_pow2 ? 1 << (max_pow2 + 4) : 0; |
| uint16_t range_shift = (font.num_tables << 4) - search_range; |
| Store16(search_range, offset, dst); |
| Store16(max_pow2, offset, dst); |
| Store16(range_shift, offset, dst); |
| |
| for (const auto& i : font.tables) { |
| if (!WriteTable(i.second, offset, dst, dst_size)) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool WriteFontCollection(const FontCollection& font_collection, uint8_t* dst, |
| size_t dst_size) { |
| size_t offset = 0; |
| |
| // It's simpler if this just a simple sfnt |
| if (font_collection.flavor != kTtcFontFlavor) { |
| return WriteFont(font_collection.fonts[0], &offset, dst, dst_size); |
| } |
| |
| // Write TTC header |
| StoreU32(kTtcFontFlavor, &offset, dst); |
| StoreU32(font_collection.header_version, &offset, dst); |
| StoreU32(font_collection.fonts.size(), &offset, dst); |
| |
| // Offset Table, zeroed for now |
| size_t offset_table = offset; // where to write offsets later |
| for (size_t i = 0; i < font_collection.fonts.size(); i++) { |
| StoreU32(0, &offset, dst); |
| } |
| |
| if (font_collection.header_version == 0x00020000) { |
| StoreU32(0, &offset, dst); // ulDsigTag |
| StoreU32(0, &offset, dst); // ulDsigLength |
| StoreU32(0, &offset, dst); // ulDsigOffset |
| } |
| |
| // Write fonts and their offsets. |
| for (size_t i = 0; i < font_collection.fonts.size(); i++) { |
| const auto& font = font_collection.fonts[i]; |
| StoreU32(offset, &offset_table, dst); |
| if (!WriteFont(font, &offset, dst, dst_size)) { |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| int NumGlyphs(const Font& font) { |
| const Font::Table* head_table = font.FindTable(kHeadTableTag); |
| const Font::Table* loca_table = font.FindTable(kLocaTableTag); |
| if (head_table == NULL || loca_table == NULL || head_table->length < 52) { |
| return 0; |
| } |
| int index_fmt = IndexFormat(font); |
| int loca_record_size = (index_fmt == 0 ? 2 : 4); |
| if (loca_table->length < loca_record_size) { |
| return 0; |
| } |
| return (loca_table->length / loca_record_size) - 1; |
| } |
| |
| int IndexFormat(const Font& font) { |
| const Font::Table* head_table = font.FindTable(kHeadTableTag); |
| if (head_table == NULL) { |
| return 0; |
| } |
| return head_table->data[51]; |
| } |
| |
| bool Font::Table::IsReused() const { |
| return this->reuse_of != NULL; |
| } |
| |
| bool GetGlyphData(const Font& font, int glyph_index, |
| const uint8_t** glyph_data, size_t* glyph_size) { |
| if (glyph_index < 0) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| const Font::Table* head_table = font.FindTable(kHeadTableTag); |
| const Font::Table* loca_table = font.FindTable(kLocaTableTag); |
| const Font::Table* glyf_table = font.FindTable(kGlyfTableTag); |
| if (head_table == NULL || loca_table == NULL || glyf_table == NULL || |
| head_table->length < 52) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| |
| int index_fmt = IndexFormat(font); |
| |
| Buffer loca_buf(loca_table->data, loca_table->length); |
| if (index_fmt == 0) { |
| uint16_t offset1, offset2; |
| if (!loca_buf.Skip(2 * glyph_index) || |
| !loca_buf.ReadU16(&offset1) || |
| !loca_buf.ReadU16(&offset2) || |
| offset2 < offset1 || |
| 2 * offset2 > glyf_table->length) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| *glyph_data = glyf_table->data + 2 * offset1; |
| *glyph_size = 2 * (offset2 - offset1); |
| } else { |
| uint32_t offset1, offset2; |
| if (!loca_buf.Skip(4 * glyph_index) || |
| !loca_buf.ReadU32(&offset1) || |
| !loca_buf.ReadU32(&offset2) || |
| offset2 < offset1 || |
| offset2 > glyf_table->length) { |
| return FONT_COMPRESSION_FAILURE(); |
| } |
| *glyph_data = glyf_table->data + offset1; |
| *glyph_size = offset2 - offset1; |
| } |
| return true; |
| } |
| |
| bool RemoveDigitalSignature(Font* font) { |
| std::map<uint32_t, Font::Table>::iterator it = |
| font->tables.find(kDsigTableTag); |
| if (it != font->tables.end()) { |
| font->tables.erase(it); |
| font->num_tables = font->tables.size(); |
| } |
| return true; |
| } |
| |
| } // namespace woff2 |