diff options
Diffstat (limited to '')
-rw-r--r-- | gfx/ots/src/name.cc | 369 |
1 files changed, 369 insertions, 0 deletions
diff --git a/gfx/ots/src/name.cc b/gfx/ots/src/name.cc new file mode 100644 index 0000000000..fc5074b058 --- /dev/null +++ b/gfx/ots/src/name.cc @@ -0,0 +1,369 @@ +// Copyright (c) 2011-2017 The OTS 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 "name.h" + +#include <algorithm> +#include <cstring> +#include <cctype> + +// name - Naming Table +// http://www.microsoft.com/typography/otspec/name.htm + +namespace { + +// We disallow characters outside the URI spec "unreserved characters" +// set; any chars outside this set will be replaced by underscore. +bool AllowedInPsName(char c) { + return isalnum(c) || std::strchr("-._~", c); +} + +bool SanitizePsNameAscii(std::string& name) { + if (name.size() > 63) + return false; + + for (unsigned i = 0; i < name.size(); ++i) { + if (!AllowedInPsName(name[i])) { + name[i] = '_'; + } + } + return true; +} + +bool SanitizePsNameUtf16Be(std::string& name) { + if ((name.size() & 1) != 0) + return false; + if (name.size() > 2 * 63) + return false; + + for (unsigned i = 0; i < name.size(); i += 2) { + if (name[i] != 0) { + // non-Latin1 char in psname? reject it altogether + return false; + } + if (!AllowedInPsName(name[i+1])) { + name[i] = '_'; + } + } + return true; +} + +void AssignToUtf16BeFromAscii(std::string* target, + const std::string& source) { + target->resize(source.size() * 2); + for (unsigned i = 0, j = 0; i < source.size(); i++) { + (*target)[j++] = '\0'; + (*target)[j++] = source[i]; + } +} + +} // namespace + + +namespace ots { + +bool OpenTypeNAME::Parse(const uint8_t* data, size_t length) { + Buffer table(data, length); + + uint16_t format = 0; + if (!table.ReadU16(&format) || format > 1) { + return Error("Failed to read table format or bad format %d", format); + } + + uint16_t count = 0; + if (!table.ReadU16(&count)) { + return Error("Failed to read name count"); + } + + uint16_t string_offset = 0; + if (!table.ReadU16(&string_offset) || string_offset > length) { + return Error("Failed to read or bad stringOffset"); + } + const char* string_base = reinterpret_cast<const char*>(data) + + string_offset; + + bool sort_required = false; + + // Read all the names, discarding any with invalid IDs, + // and any where the offset/length would be outside the table. + // A stricter alternative would be to reject the font if there + // are invalid name records, but it's not clear that is necessary. + for (unsigned i = 0; i < count; ++i) { + NameRecord rec; + uint16_t name_length, name_offset = 0; + if (!table.ReadU16(&rec.platform_id) || + !table.ReadU16(&rec.encoding_id) || + !table.ReadU16(&rec.language_id) || + !table.ReadU16(&rec.name_id) || + !table.ReadU16(&name_length) || + !table.ReadU16(&name_offset)) { + return Error("Failed to read name entry %d", i); + } + // check platform & encoding, discard names with unknown values + switch (rec.platform_id) { + case 0: // Unicode + if (rec.encoding_id > 6) { + continue; + } + break; + case 1: // Macintosh + if (rec.encoding_id > 32) { + continue; + } + break; + case 2: // ISO + if (rec.encoding_id > 2) { + continue; + } + break; + case 3: // Windows: IDs 7 to 9 are "reserved" + if (rec.encoding_id > 6 && rec.encoding_id != 10) { + continue; + } + break; + case 4: // Custom (OTF Windows NT compatibility) + if (rec.encoding_id > 255) { + continue; + } + break; + default: // unknown platform + continue; + } + + const unsigned name_end = static_cast<unsigned>(string_offset) + + name_offset + name_length; + if (name_end > length) { + continue; + } + rec.text.resize(name_length); + rec.text.assign(string_base + name_offset, name_length); + + if (rec.name_id == 6) { + // PostScript name: "sanitize" it by replacing any chars outside the + // URI spec "unreserved" set by underscore, or reject the name entirely + // (and use a fallback) if it looks really broken. + if (rec.platform_id == 1) { + if (!SanitizePsNameAscii(rec.text)) { + continue; + } + } else if (rec.platform_id == 0 || rec.platform_id == 3) { + if (!SanitizePsNameUtf16Be(rec.text)) { + continue; + } + } + } + + if (!this->names.empty() && !(this->names.back() < rec)) { + Warning("name records are not sorted."); + sort_required = true; + } + + this->names.push_back(rec); + this->name_ids.insert(rec.name_id); + } + + if (format == 1) { + // extended name table format with language tags + uint16_t lang_tag_count; + if (!table.ReadU16(&lang_tag_count)) { + return Error("Failed to read langTagCount"); + } + for (unsigned i = 0; i < lang_tag_count; ++i) { + uint16_t tag_length = 0; + uint16_t tag_offset = 0; + if (!table.ReadU16(&tag_length) || !table.ReadU16(&tag_offset)) { + return Error("Faile to read length or offset for langTagRecord %d", i); + } + const unsigned tag_end = static_cast<unsigned>(string_offset) + + tag_offset + tag_length; + if (tag_end > length) { + return Error("bad end of tag %d > %ld for langTagRecord %d", tag_end, length, i); + } + // Lang tag is BCP 47 tag per the spec, the recommonded BCP 47 max tag + // length is 35: + // https://tools.ietf.org/html/bcp47#section-4.4.1 + // We are being too generous and allowing for 100 (multiplied by 2 since + // this is UTF-16 string). + if (tag_length > 100 * 2) { + return Error("Too long language tag for LangTagRecord %d: %d", i, tag_length); + } + std::string tag(string_base + tag_offset, tag_length); + this->lang_tags.push_back(tag); + } + } + + if (table.offset() > string_offset) { + // the string storage apparently overlapped the name/tag records; + // consider this font to be badly broken + return Error("Bad table offset %ld > %d", table.offset(), string_offset); + } + + // check existence of required name strings (synthesize if necessary) + // [0 - copyright - skip] + // 1 - family + // 2 - subfamily + // [3 - unique ID - skip] + // 4 - full name + // 5 - version + // 6 - postscript name + static const uint16_t kStdNameCount = 7; + static const char* kStdNames[kStdNameCount] = { + NULL, + "OTS derived font", + "Unspecified", + NULL, + "OTS derived font", + "1.000", + "OTS-derived-font" + }; + + // scan the names to check whether the required "standard" ones are present; + // if not, we'll add our fixed versions here + bool mac_name[kStdNameCount] = { 0 }; + bool win_name[kStdNameCount] = { 0 }; + for (const auto& name : this->names) { + const uint16_t id = name.name_id; + if (id >= kStdNameCount || kStdNames[id] == NULL) { + continue; + } + if (name.platform_id == 1) { + mac_name[id] = true; + continue; + } + if (name.platform_id == 3) { + win_name[id] = true; + continue; + } + } + + for (uint16_t i = 0; i < kStdNameCount; ++i) { + if (kStdNames[i] == NULL) { + continue; + } + if (!mac_name[i] && !win_name[i]) { + NameRecord mac_rec(1 /* platform_id */, 0 /* encoding_id */, + 0 /* language_id */ , i /* name_id */); + mac_rec.text.assign(kStdNames[i]); + + NameRecord win_rec(3 /* platform_id */, 1 /* encoding_id */, + 1033 /* language_id */ , i /* name_id */); + AssignToUtf16BeFromAscii(&win_rec.text, std::string(kStdNames[i])); + + this->names.push_back(mac_rec); + this->names.push_back(win_rec); + sort_required = true; + } + } + + if (sort_required) { + std::sort(this->names.begin(), this->names.end()); + } + + return true; +} + +bool OpenTypeNAME::Serialize(OTSStream* out) { + uint16_t name_count = static_cast<uint16_t>(this->names.size()); + uint16_t lang_tag_count = static_cast<uint16_t>(this->lang_tags.size()); + uint16_t format = 0; + size_t string_offset = 6 + name_count * 12; + + if (this->lang_tags.size() > 0) { + // lang tags require a format-1 name table + format = 1; + string_offset += 2 + lang_tag_count * 4; + } + if (string_offset > 0xffff) { + return Error("Bad stringOffset: %ld", string_offset); + } + if (!out->WriteU16(format) || + !out->WriteU16(name_count) || + !out->WriteU16(static_cast<uint16_t>(string_offset))) { + return Error("Failed to write name header"); + } + + std::string string_data; + for (const auto& rec : this->names) { + if (string_data.size() + rec.text.size() > + std::numeric_limits<uint16_t>::max() || + !out->WriteU16(rec.platform_id) || + !out->WriteU16(rec.encoding_id) || + !out->WriteU16(rec.language_id) || + !out->WriteU16(rec.name_id) || + !out->WriteU16(static_cast<uint16_t>(rec.text.size())) || + !out->WriteU16(static_cast<uint16_t>(string_data.size())) ) { + return Error("Faile to write nameRecord"); + } + string_data.append(rec.text); + } + + if (format == 1) { + if (!out->WriteU16(lang_tag_count)) { + return Error("Faile to write langTagCount"); + } + for (const auto& tag : this->lang_tags) { + if (string_data.size() + tag.size() > + std::numeric_limits<uint16_t>::max() || + !out->WriteU16(static_cast<uint16_t>(tag.size())) || + !out->WriteU16(static_cast<uint16_t>(string_data.size()))) { + return Error("Failed to write langTagRecord"); + } + string_data.append(tag); + } + } + + if (!out->Write(string_data.data(), string_data.size())) { + return Error("Faile to write string data"); + } + + return true; +} + +bool OpenTypeNAME::IsValidNameId(uint16_t nameID, bool addIfMissing) { + if (addIfMissing && !this->name_ids.count(nameID)) { + bool added_unicode = false; + bool added_macintosh = false; + bool added_windows = false; + const size_t names_size = this->names.size(); // original size + for (size_t i = 0; i < names_size; ++i) switch (names[i].platform_id) { + case 0: + if (!added_unicode) { + // If there is an existing NameRecord with platform_id == 0 (Unicode), + // then add a NameRecord for the the specified nameID with arguments + // 0 (Unicode), 0 (v1.0), 0 (unspecified language). + this->names.emplace_back(0, 0, 0, nameID); + this->names.back().text = "NoName"; + added_unicode = true; + } + break; + case 1: + if (!added_macintosh) { + // If there is an existing NameRecord with platform_id == 1 (Macintosh), + // then add a NameRecord for the specified nameID with arguments + // 1 (Macintosh), 0 (Roman), 0 (English). + this->names.emplace_back(1, 0, 0, nameID); + this->names.back().text = "NoName"; + added_macintosh = true; + } + break; + case 3: + if (!added_windows) { + // If there is an existing NameRecord with platform_id == 3 (Windows), + // then add a NameRecord for the specified nameID with arguments + // 3 (Windows), 1 (UCS), 1033 (US English). + this->names.emplace_back(3, 1, 1033, nameID); + this->names.back().text = "NoName"; + added_windows = true; + } + break; + } + if (added_unicode || added_macintosh || added_windows) { + std::sort(this->names.begin(), this->names.end()); + this->name_ids.insert(nameID); + } + } + return this->name_ids.count(nameID); +} + +} // namespace |