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 // 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 "name.h"

 #include <algorithm>

 #include <cstring>

 #include "cff.h"

 // name - Naming Table

 // http://www.microsoft.com/typography/otspec/name.htm

 #define TABLE_NAME "name"

 namespace {

 bool ValidInPsName(char c) {

   return (c > 0x20 && c < 0x7f && !std::strchr("[](){}<>/%", c));

 }

 bool CheckPsNameAscii(const std::string& name) {

   for (unsigned i = 0; i < name.size(); ++i) {

     if (!ValidInPsName(name[i])) {

       return false;

     }

   }

   return true;

 }

 bool CheckPsNameUtf16Be(const std::string& name) {

   if ((name.size() & 1) != 0)

     return false;

   for (unsigned i = 0; i < name.size(); i += 2) {

     if (name[i] != 0) {

       return false;

     }

     if (!ValidInPsName(name[i+1])) {

       return false;

     }

   }

   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 ots_name_parse(OpenTypeFile* file, const uint8_t* data, size_t length) {

   Buffer table(data, length);

   OpenTypeNAME* name = new OpenTypeNAME;

   file->name = name;

   uint16_t format = 0;

   if (!table.ReadU16(&format) || format > 1) {

     return OTS_FAILURE_MSG("Failed to read name table format or bad format %d", format);

   }

   uint16_t count = 0;

   if (!table.ReadU16(&count)) {

     return OTS_FAILURE_MSG("Failed to read name count");

   }

   uint16_t string_offset = 0;

   if (!table.ReadU16(&string_offset) || string_offset > length) {

     return OTS_FAILURE_MSG("Failed to read strings offset");

   }

   const char* string_base = reinterpret_cast<const char*>(data) +

       string_offset;

   NameRecord prev_record;

   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;

     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 OTS_FAILURE_MSG("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: check that it is valid, if not then discard it

       if (rec.platform_id == 1) {

         if (file->cff && !file->cff->name.empty()) {

           rec.text = file->cff->name;

         } else if (!CheckPsNameAscii(rec.text)) {

           continue;

         }

       } else if (rec.platform_id == 0 || rec.platform_id == 3) {

         if (file->cff && !file->cff->name.empty()) {

           AssignToUtf16BeFromAscii(&rec.text, file->cff->name);

         } else if (!CheckPsNameUtf16Be(rec.text)) {

           continue;

         }

       }

     }

     if ((i > 0) && !(prev_record < rec)) {

       OTS_WARNING("name records are not sorted.");

       sort_required = true;

     }

     name->names.push_back(rec);

     prev_record = rec;

   }

   if (format == 1) {

     // extended name table format with language tags

     uint16_t lang_tag_count;

     if (!table.ReadU16(&lang_tag_count)) {

       return OTS_FAILURE_MSG("Failed to read language tag count");

     }

     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 OTS_FAILURE_MSG("Faile to read tag length or offset");

       }

       const unsigned tag_end = static_cast<unsigned>(string_offset) +

           tag_offset + tag_length;

       if (tag_end > length) {

         return OTS_FAILURE_MSG("bad end of tag %d > %ld for name entry %d", tag_end, length, i);

       }

       std::string tag(string_base + tag_offset, tag_length);

       name->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 OTS_FAILURE_MSG("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 unsigned kStdNameCount = 7;

   static const char* kStdNames[kStdNameCount] = {

     NULL,

     "OTS derived font",

     "Unspecified",

     NULL,

     "OTS derived font",

     "1.000",

     "OTS-derived-font"

   };

   // The spec says that "In CFF OpenType fonts, these two name strings, when

   // translated to ASCII, must also be identical to the font name as stored in

   // the CFF's Name INDEX." And actually, Mac OS X's font parser requires that.

   if (file->cff && !file->cff->name.empty()) {

     kStdNames[6] = file->cff->name.c_str();

   }

   // 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 (std::vector<NameRecord>::iterator name_iter = name->names.begin();

        name_iter != name->names.end(); name_iter++) {

     const uint16_t id = name_iter->name_id;

     if (id >= kStdNameCount || kStdNames[id] == NULL) {

       continue;

     }

     if (name_iter->platform_id == 1) {

       mac_name[id] = true;

       continue;

     }

     if (name_iter->platform_id == 3) {

       win_name[id] = true;

       continue;

     }

   }

   for (unsigned i = 0; i < kStdNameCount; ++i) {

     if (kStdNames[i] == NULL) {

       continue;

     }

     if (!mac_name[i]) {

       NameRecord rec(1 /* platform_id */, 0 /* encoding_id */,

                      0 /* language_id */ , i /* name_id */);

       rec.text.assign(kStdNames[i]);

       name->names.push_back(rec);

       sort_required = true;

     }

     if (!win_name[i]) {

       NameRecord rec(3 /* platform_id */, 1 /* encoding_id */,

                      1033 /* language_id */ , i /* name_id */);

       AssignToUtf16BeFromAscii(&rec.text, std::string(kStdNames[i]));

       name->names.push_back(rec);

       sort_required = true;

     }

   }

   if (sort_required) {

     std::sort(name->names.begin(), name->names.end());

   }

   return true;

 }

 bool ots_name_should_serialise(OpenTypeFile* file) {

   return file->name != NULL;

 }

 bool ots_name_serialise(OTSStream* out, OpenTypeFile* file) {

   const OpenTypeNAME* name = file->name;

   uint16_t name_count = name->names.size();

   uint16_t lang_tag_count = name->lang_tags.size();

   uint16_t format = 0;

   size_t string_offset = 6 + name_count * 12;

   if (name->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 OTS_FAILURE_MSG("Bad string offset %ld", string_offset);

   }

   if (!out->WriteU16(format) ||

       !out->WriteU16(name_count) ||

       !out->WriteU16(string_offset)) {

     return OTS_FAILURE_MSG("Failed to write name header");

   }

   std::string string_data;

   for (std::vector<NameRecord>::const_iterator name_iter = name->names.begin();

        name_iter != name->names.end(); name_iter++) {

     const NameRecord& rec = *name_iter;

     if (!out->WriteU16(rec.platform_id) ||

         !out->WriteU16(rec.encoding_id) ||

         !out->WriteU16(rec.language_id) ||

         !out->WriteU16(rec.name_id) ||

         !out->WriteU16(rec.text.size()) ||

         !out->WriteU16(string_data.size()) ) {

       return OTS_FAILURE_MSG("Faile to write name entry");

     }

     string_data.append(rec.text);

   }

   if (format == 1) {

     if (!out->WriteU16(lang_tag_count)) {

       return OTS_FAILURE_MSG("Faile to write language tag count");

     }

     for (std::vector<std::string>::const_iterator tag_iter =

              name->lang_tags.begin();

          tag_iter != name->lang_tags.end(); tag_iter++) {

       if (!out->WriteU16(tag_iter->size()) ||

           !out->WriteU16(string_data.size())) {

         return OTS_FAILURE_MSG("Failed to write string");

       }

       string_data.append(*tag_iter);

     }

   }

   if (!out->Write(string_data.data(), string_data.size())) {

     return OTS_FAILURE_MSG("Faile to write string data");

   }

   return true;

 }

 void ots_name_free(OpenTypeFile* file) {

   delete file->name;

 }

 }  // namespace