//========================================================================
//
// FoFiTrueType.cc
//
// Copyright 1999-2003 Glyph & Cog, LLC
//
//========================================================================

//========================================================================
//
// Modified under the Poppler project - http://poppler.freedesktop.org
//
// All changes made under the Poppler project to this file are licensed
// under GPL version 2 or later
//
// Copyright (C) 2006 Takashi Iwai <tiwai@suse.de>
// Copyright (C) 2007 Koji Otani <sho@bbr.jp>
// Copyright (C) 2007 Carlos Garcia Campos <carlosgc@gnome.org>
// Copyright (C) 2008, 2009, 2012, 2014-2018 Albert Astals Cid <aacid@kde.org>
// Copyright (C) 2008 Tomas Are Haavet <tomasare@gmail.com>
// Copyright (C) 2012 Suzuki Toshiya <mpsuzuki@hiroshima-u.ac.jp>
// Copyright (C) 2012, 2017 Adrian Johnson <ajohnson@redneon.com>
// Copyright (C) 2014 Thomas Freitag <Thomas.Freitag@alfa.de>
// Copyright (C) 2015 Aleksei Volkov <Aleksei Volkov>
// Copyright (C) 2015, 2016 William Bader <williambader@hotmail.com>
// Copyright (C) 2018 Adam Reichold <adam.reichold@t-online.de>
//
// To see a description of the changes please see the Changelog file that
// came with your tarball or type make ChangeLog if you are building from git
//
//========================================================================

#include <config.h>

#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <algorithm>
#include "goo/gtypes.h"
#include "goo/gmem.h"
#include "goo/GooLikely.h"
#include "goo/GooString.h"
#include "FoFiType1C.h"
#include "FoFiTrueType.h"
#include "poppler/Error.h"

//
// Terminology
// -----------
//
// character code = number used as an element of a text string
//
// character name = glyph name = name for a particular glyph within a
//                  font
//
// glyph index = GID = position (within some internal table in the font)
//               where the instructions to draw a particular glyph are
//               stored
//
// Type 1 fonts
// ------------
//
// Type 1 fonts contain:
//
// Encoding: array of glyph names, maps char codes to glyph names
//
//           Encoding[charCode] = charName
//
// CharStrings: dictionary of instructions, keyed by character names,
//              maps character name to glyph data
//
//              CharStrings[charName] = glyphData
//
// TrueType fonts
// --------------
//
// TrueType fonts contain:
//
// 'cmap' table: mapping from character code to glyph index; there may
//               be multiple cmaps in a TrueType font
//
//               cmap[charCode] = gid
//
// 'post' table: mapping from glyph index to glyph name
//
//               post[gid] = glyphName
//
// Type 42 fonts
// -------------
//
// Type 42 fonts contain:
//
// Encoding: array of glyph names, maps char codes to glyph names
//
//           Encoding[charCode] = charName
//
// CharStrings: dictionary of glyph indexes, keyed by character names,
//              maps character name to glyph index
//
//              CharStrings[charName] = gid
//

//------------------------------------------------------------------------

#define ttcfTag 0x74746366

//------------------------------------------------------------------------

struct TrueTypeTable {
  unsigned int tag;
  unsigned int checksum;
  int offset;
  int origOffset;
  int len;
};

struct TrueTypeCmap {
  int platform;
  int encoding;
  int offset;
  int len;
  int fmt;
};

struct TrueTypeLoca {
  int idx;
  int origOffset;
  int newOffset;
  int len;
};

#define cmapTag 0x636d6170
#define glyfTag 0x676c7966
#define headTag 0x68656164
#define hheaTag 0x68686561
#define hmtxTag 0x686d7478
#define locaTag 0x6c6f6361
#define nameTag 0x6e616d65
#define os2Tag  0x4f532f32
#define postTag 0x706f7374
#define vrt2Tag 0x76727432
#define vertTag 0x76657274

struct cmpTrueTypeLocaOffsetFunctor {
  bool operator()(const TrueTypeLoca loca1, const TrueTypeLoca loca2) {
    if (loca1.origOffset == loca2.origOffset) {
      return loca1.idx < loca2.idx;
    }
    return loca1.origOffset < loca2.origOffset;
  }
};

struct cmpTrueTypeLocaIdxFunctor {
  bool operator()(const TrueTypeLoca loca1, const TrueTypeLoca loca2) {
    return loca1.idx < loca2.idx;
  }
};

struct cmpTrueTypeTableTagFunctor {
  bool operator()(const TrueTypeTable &tab1, const TrueTypeTable &tab2) {
    return tab1.tag < tab2.tag;
  }
};

//------------------------------------------------------------------------

struct T42Table {
  const char *tag;		// 4-byte tag
  bool required;		// required by the TrueType spec?
};

// TrueType tables to be embedded in Type 42 fonts.
// NB: the table names must be in alphabetical order here.
#define nT42Tables 11
static T42Table t42Tables[nT42Tables] = {
  { "cvt ", true  },
  { "fpgm", true  },
  { "glyf", true  },
  { "head", true  },
  { "hhea", true  },
  { "hmtx", true  },
  { "loca", true  },
  { "maxp", true  },
  { "prep", true  },
  { "vhea", false },
  { "vmtx", false }
};
#define t42HeadTable  3
#define t42LocaTable  6
#define t42GlyfTable  2
#define t42VheaTable  9
#define t42VmtxTable 10

//------------------------------------------------------------------------

// Glyph names in some arbitrary standard order that Apple uses for
// their TrueType fonts.
static const char *macGlyphNames[258] = {
  ".notdef",        "null",           "CR",             "space",
  "exclam",         "quotedbl",       "numbersign",     "dollar",
  "percent",        "ampersand",      "quotesingle",    "parenleft",
  "parenright",     "asterisk",       "plus",           "comma",
  "hyphen",         "period",         "slash",          "zero",
  "one",            "two",            "three",          "four",
  "five",           "six",            "seven",          "eight",
  "nine",           "colon",          "semicolon",      "less",
  "equal",          "greater",        "question",       "at",
  "A",              "B",              "C",              "D",
  "E",              "F",              "G",              "H",
  "I",              "J",              "K",              "L",
  "M",              "N",              "O",              "P",
  "Q",              "R",              "S",              "T",
  "U",              "V",              "W",              "X",
  "Y",              "Z",              "bracketleft",    "backslash",
  "bracketright",   "asciicircum",    "underscore",     "grave",
  "a",              "b",              "c",              "d",
  "e",              "f",              "g",              "h",
  "i",              "j",              "k",              "l",
  "m",              "n",              "o",              "p",
  "q",              "r",              "s",              "t",
  "u",              "v",              "w",              "x",
  "y",              "z",              "braceleft",      "bar",
  "braceright",     "asciitilde",     "Adieresis",      "Aring",
  "Ccedilla",       "Eacute",         "Ntilde",         "Odieresis",
  "Udieresis",      "aacute",         "agrave",         "acircumflex",
  "adieresis",      "atilde",         "aring",          "ccedilla",
  "eacute",         "egrave",         "ecircumflex",    "edieresis",
  "iacute",         "igrave",         "icircumflex",    "idieresis",
  "ntilde",         "oacute",         "ograve",         "ocircumflex",
  "odieresis",      "otilde",         "uacute",         "ugrave",
  "ucircumflex",    "udieresis",      "dagger",         "degree",
  "cent",           "sterling",       "section",        "bullet",
  "paragraph",      "germandbls",     "registered",     "copyright",
  "trademark",      "acute",          "dieresis",       "notequal",
  "AE",             "Oslash",         "infinity",       "plusminus",
  "lessequal",      "greaterequal",   "yen",            "mu",
  "partialdiff",    "summation",      "product",        "pi",
  "integral",       "ordfeminine",    "ordmasculine",   "Omega",
  "ae",             "oslash",         "questiondown",   "exclamdown",
  "logicalnot",     "radical",        "florin",         "approxequal",
  "increment",      "guillemotleft",  "guillemotright", "ellipsis",
  "nbspace",        "Agrave",         "Atilde",         "Otilde",
  "OE",             "oe",             "endash",         "emdash",
  "quotedblleft",   "quotedblright",  "quoteleft",      "quoteright",
  "divide",         "lozenge",        "ydieresis",      "Ydieresis",
  "fraction",       "currency",       "guilsinglleft",  "guilsinglright",
  "fi",             "fl",             "daggerdbl",      "periodcentered",
  "quotesinglbase", "quotedblbase",   "perthousand",    "Acircumflex",
  "Ecircumflex",    "Aacute",         "Edieresis",      "Egrave",
  "Iacute",         "Icircumflex",    "Idieresis",      "Igrave",
  "Oacute",         "Ocircumflex",    "applelogo",      "Ograve",
  "Uacute",         "Ucircumflex",    "Ugrave",         "dotlessi",
  "circumflex",     "tilde",          "overscore",      "breve",
  "dotaccent",      "ring",           "cedilla",        "hungarumlaut",
  "ogonek",         "caron",          "Lslash",         "lslash",
  "Scaron",         "scaron",         "Zcaron",         "zcaron",
  "brokenbar",      "Eth",            "eth",            "Yacute",
  "yacute",         "Thorn",          "thorn",          "minus",
  "multiply",       "onesuperior",    "twosuperior",    "threesuperior",
  "onehalf",        "onequarter",     "threequarters",  "franc",
  "Gbreve",         "gbreve",         "Idot",           "Scedilla",
  "scedilla",       "Cacute",         "cacute",         "Ccaron",
  "ccaron",         "dmacron"
};

//------------------------------------------------------------------------
// FoFiTrueType
//------------------------------------------------------------------------

FoFiTrueType *FoFiTrueType::make(const char *fileA, int lenA, int faceIndexA) {
  FoFiTrueType *ff;

  ff = new FoFiTrueType(fileA, lenA, false, faceIndexA);
  if (!ff->parsedOk) {
    delete ff;
    return nullptr;
  }
  return ff;
}

FoFiTrueType *FoFiTrueType::load(const char *fileName, int faceIndexA) {
  FoFiTrueType *ff;
  char *fileA;
  int lenA;

  if (!(fileA = FoFiBase::readFile(fileName, &lenA))) {
    return nullptr;
  }
  ff = new FoFiTrueType(fileA, lenA, true, faceIndexA);
  if (!ff->parsedOk) {
    delete ff;
    return nullptr;
  }
  return ff;
}

FoFiTrueType::FoFiTrueType(const char *fileA, int lenA, bool freeFileDataA, int faceIndexA):
  FoFiBase(fileA, lenA, freeFileDataA)
{
  tables = nullptr;
  nTables = 0;
  cmaps = nullptr;
  nCmaps = 0;
  parsedOk = false;
  faceIndex = faceIndexA;
  gsubFeatureTable = 0;
  gsubLookupList = 0;

  parse();
}

FoFiTrueType::~FoFiTrueType() {
  gfree(tables);
  gfree(cmaps);
}

int FoFiTrueType::getNumCmaps() const {
  return nCmaps;
}

int FoFiTrueType::getCmapPlatform(int i) const {
  return cmaps[i].platform;
}

int FoFiTrueType::getCmapEncoding(int i) const {
  return cmaps[i].encoding;
}

int FoFiTrueType::findCmap(int platform, int encoding) const {
  int i;

  for (i = 0; i < nCmaps; ++i) {
    if (cmaps[i].platform == platform && cmaps[i].encoding == encoding) {
      return i;
    }
  }
  return -1;
}

int FoFiTrueType::mapCodeToGID(int i, unsigned int c) const {
  int gid;
  unsigned int segCnt, segEnd, segStart, segDelta, segOffset;
  unsigned int cmapFirst, cmapLen;
  int pos, a, b, m;
  bool ok;

  if (i < 0 || i >= nCmaps) {
    return 0;
  }
  ok = true;
  pos = cmaps[i].offset;
  switch (cmaps[i].fmt) {
  case 0:
    if (c + 6 >= (unsigned int)cmaps[i].len) {
      return 0;
    }
    gid = getU8(cmaps[i].offset + 6 + c, &ok);
    break;
  case 4:
    segCnt = getU16BE(pos + 6, &ok) / 2;
    a = -1;
    b = segCnt - 1;
    segEnd = getU16BE(pos + 14 + 2*b, &ok);
    if (c > segEnd) {
      // malformed font -- the TrueType spec requires the last segEnd
      // to be 0xffff
      return 0;
    }
    // invariant: seg[a].end < code <= seg[b].end
    while (b - a > 1 && ok) {
      m = (a + b) / 2;
      segEnd = getU16BE(pos + 14 + 2*m, &ok);
      if (segEnd < c) {
	a = m;
      } else {
	b = m;
      }
    }
    segStart = getU16BE(pos + 16 + 2*segCnt + 2*b, &ok);
    segDelta = getU16BE(pos + 16 + 4*segCnt + 2*b, &ok);
    segOffset = getU16BE(pos + 16 + 6*segCnt + 2*b, &ok);
    if (c < segStart) {
      return 0;
    }
    if (segOffset == 0) {
      gid = (c + segDelta) & 0xffff;
    } else {
      gid = getU16BE(pos + 16 + 6*segCnt + 2*b +
		       segOffset + 2 * (c - segStart), &ok);
      if (gid != 0) {
	gid = (gid + segDelta) & 0xffff;
      }
    }
    break;
  case 6:
    cmapFirst = getU16BE(pos + 6, &ok);
    cmapLen = getU16BE(pos + 8, &ok);
    if (c < cmapFirst || c >= cmapFirst + cmapLen) {
      return 0;
    }
    gid = getU16BE(pos + 10 + 2 * (c - cmapFirst), &ok);
    break;
  case 12:
    segCnt = getU32BE(pos + 12, &ok);
    a = -1;
    b = segCnt - 1;
    segEnd = getU32BE(pos + 16 + 12*b+4, &ok);
    if (c > segEnd) {
      return 0;
    }
    // invariant: seg[a].end < code <= seg[b].end
    while (b - a > 1 && ok) {
      m = (a + b) / 2;
      segEnd = getU32BE(pos + 16 + 12*m+4, &ok);
      if (segEnd < c) {
	a = m;
      } else {
	b = m;
      }
    }
    segStart = getU32BE(pos + 16 + 12*b, &ok);
    segDelta = getU32BE(pos + 16 + 12*b+8, &ok);
    if (c < segStart) {
      return 0;
    }
    gid = segDelta + (c-segStart);
    break;
  default:
    return 0;
  }
  if (!ok) {
    return 0;
  }
  return gid;
}

int FoFiTrueType::mapNameToGID(const char *name) const {
  const auto gid = nameToGID.find(name);
  if (gid == nameToGID.end()) {
    return 0;
  }
  return gid->second;
}

bool FoFiTrueType::getCFFBlock(char **start, int *length) const {
  int i;

  if (!openTypeCFF || !tables) {
    return false;
  }
  i = seekTable("CFF ");
  if (!checkRegion(tables[i].offset, tables[i].len)) {
    return false;
  }
  *start = (char *)file + tables[i].offset;
  *length = tables[i].len;
  return true;
}

int *FoFiTrueType::getCIDToGIDMap(int *nCIDs) const {
  char *start;
  int length;
  FoFiType1C *ff;
  int *map;

  *nCIDs = 0;
  if (!getCFFBlock(&start, &length)) {
    return nullptr;
  }
  if (!(ff = FoFiType1C::make(start, length))) {
    return nullptr;
  }
  map = ff->getCIDToGIDMap(nCIDs);
  delete ff;
  return map;
}

int FoFiTrueType::getEmbeddingRights() const {
  int i, fsType;
  bool ok;

  if ((i = seekTable("OS/2")) < 0) {
    return 4;
  }
  ok = true;
  fsType = getU16BE(tables[i].offset + 8, &ok);
  if (!ok) {
    return 4;
  }
  if (fsType & 0x0008) {
    return 2;
  }
  if (fsType & 0x0004) {
    return 1;
  }
  if (fsType & 0x0002) {
    return 0;
  }
  return 3;
}

void FoFiTrueType::getFontMatrix(double *mat) const {
  char *start;
  int length;
  FoFiType1C *ff;

  if (!getCFFBlock(&start, &length)) {
    return;
  }
  if (!(ff = FoFiType1C::make(start, length))) {
    return;
  }
  ff->getFontMatrix(mat);
  delete ff;
}

void FoFiTrueType::convertToType42(const char *psName, char **encoding,
				   int *codeToGID,
				   FoFiOutputFunc outputFunc,
				   void *outputStream) const {
  GooString *buf;
  int maxUsedGlyph;
  bool ok;

  if (openTypeCFF) {
    return;
  }

  // write the header
  ok = true;
  buf = GooString::format("%!PS-TrueTypeFont-{0:2g}\n",
			(double)getS32BE(0, &ok) / 65536.0);
  (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
  delete buf;

  // begin the font dictionary
  (*outputFunc)(outputStream, "10 dict begin\n", 14);
  (*outputFunc)(outputStream, "/FontName /", 11);
  (*outputFunc)(outputStream, psName, strlen(psName));
  (*outputFunc)(outputStream, " def\n", 5);
  (*outputFunc)(outputStream, "/FontType 42 def\n", 17);
  (*outputFunc)(outputStream, "/FontMatrix [1 0 0 1 0 0] def\n", 30);
  buf = GooString::format("/FontBBox [{0:d} {1:d} {2:d} {3:d}] def\n",
			bbox[0], bbox[1], bbox[2], bbox[3]);
  (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
  delete buf;
  (*outputFunc)(outputStream, "/PaintType 0 def\n", 17);

  // write the guts of the dictionary
  cvtEncoding(encoding, outputFunc, outputStream);
  cvtCharStrings(encoding, codeToGID, outputFunc, outputStream);
  cvtSfnts(outputFunc, outputStream, nullptr, false, &maxUsedGlyph);

  // end the dictionary and define the font
  (*outputFunc)(outputStream, "FontName currentdict end definefont pop\n", 40);
}

void FoFiTrueType::convertToType1(const char *psName, const char **newEncoding,
				  bool ascii, FoFiOutputFunc outputFunc,
				  void *outputStream) const {
  char *start;
  int length;
  FoFiType1C *ff;

  if (!getCFFBlock(&start, &length)) {
    return;
  }
  if (!(ff = FoFiType1C::make(start, length))) {
    return;
  }
  ff->convertToType1(psName, newEncoding, ascii, outputFunc, outputStream);
  delete ff;
}

void FoFiTrueType::convertToCIDType2(const char *psName,
				     int *cidMap, int nCIDs,
				     bool needVerticalMetrics,
				     FoFiOutputFunc outputFunc,
				     void *outputStream) const {
  GooString *buf;
  int cid, maxUsedGlyph;
  bool ok;
  int i, j, k;

  if (openTypeCFF) {
    return;
  }

  // write the header
  ok = true;
  buf = GooString::format("%!PS-TrueTypeFont-{0:2g}\n",
			(double)getS32BE(0, &ok) / 65536.0);
  (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
  delete buf;

  // begin the font dictionary
  (*outputFunc)(outputStream, "20 dict begin\n", 14);
  (*outputFunc)(outputStream, "/CIDFontName /", 14);
  (*outputFunc)(outputStream, psName, strlen(psName));
  (*outputFunc)(outputStream, " def\n", 5);
  (*outputFunc)(outputStream, "/CIDFontType 2 def\n", 19);
  (*outputFunc)(outputStream, "/FontType 42 def\n", 17);
  (*outputFunc)(outputStream, "/CIDSystemInfo 3 dict dup begin\n", 32);
  (*outputFunc)(outputStream, "  /Registry (Adobe) def\n", 24);
  (*outputFunc)(outputStream, "  /Ordering (Identity) def\n", 27);
  (*outputFunc)(outputStream, "  /Supplement 0 def\n", 20);
  (*outputFunc)(outputStream, "  end def\n", 10);
  (*outputFunc)(outputStream, "/GDBytes 2 def\n", 15);
  if (cidMap) {
    buf = GooString::format("/CIDCount {0:d} def\n", nCIDs);
    (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
    delete buf;
    if (nCIDs > 32767) {
      (*outputFunc)(outputStream, "/CIDMap [", 9);
      for (i = 0; i < nCIDs; i += 32768 - 16) {
	(*outputFunc)(outputStream, "<\n", 2);
	for (j = 0; j < 32768 - 16 && i+j < nCIDs; j += 16) {
	  (*outputFunc)(outputStream, "  ", 2);
	  for (k = 0; k < 16 && i+j+k < nCIDs; ++k) {
	    cid = cidMap[i+j+k];
	    buf = GooString::format("{0:02x}{1:02x}",
				  (cid >> 8) & 0xff, cid & 0xff);
	    (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
	    delete buf;
	  }
	  (*outputFunc)(outputStream, "\n", 1);
	}
	(*outputFunc)(outputStream, "  >", 3);
      }
      (*outputFunc)(outputStream, "\n", 1);
      (*outputFunc)(outputStream, "] def\n", 6);
    } else {
      (*outputFunc)(outputStream, "/CIDMap <\n", 10);
      for (i = 0; i < nCIDs; i += 16) {
	(*outputFunc)(outputStream, "  ", 2);
	for (j = 0; j < 16 && i+j < nCIDs; ++j) {
	  cid = cidMap[i+j];
	  buf = GooString::format("{0:02x}{1:02x}",
				(cid >> 8) & 0xff, cid & 0xff);
	  (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
	  delete buf;
	}
	(*outputFunc)(outputStream, "\n", 1);
      }
      (*outputFunc)(outputStream, "> def\n", 6);
    }
  } else {
    // direct mapping - just fill the string(s) with s[i]=i
    buf = GooString::format("/CIDCount {0:d} def\n", nGlyphs);
    (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
    delete buf;
    if (nGlyphs > 32767) {
      (*outputFunc)(outputStream, "/CIDMap [\n", 10);
      for (i = 0; i < nGlyphs; i += 32767) {
	j = nGlyphs - i < 32767 ? nGlyphs - i : 32767;
	buf = GooString::format("  {0:d} string 0 1 {1:d} {{\n", 2 * j, j - 1);
	(*outputFunc)(outputStream, buf->c_str(), buf->getLength());
	delete buf;
	buf = GooString::format("    2 copy dup 2 mul exch {0:d} add -8 bitshift put\n",
			      i);
	(*outputFunc)(outputStream, buf->c_str(), buf->getLength());
	delete buf;
	buf = GooString::format("    1 index exch dup 2 mul 1 add exch {0:d} add"
			      " 255 and put\n", i);
	(*outputFunc)(outputStream, buf->c_str(), buf->getLength());
	delete buf;
	(*outputFunc)(outputStream, "  } for\n", 8);
      }
      (*outputFunc)(outputStream, "] def\n", 6);
    } else {
      buf = GooString::format("/CIDMap {0:d} string\n", 2 * nGlyphs);
      (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
      delete buf;
      buf = GooString::format("  0 1 {0:d} {{\n", nGlyphs - 1);
      (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
      delete buf;
      (*outputFunc)(outputStream,
		    "    2 copy dup 2 mul exch -8 bitshift put\n", 42);
      (*outputFunc)(outputStream,
		    "    1 index exch dup 2 mul 1 add exch 255 and put\n", 50);
      (*outputFunc)(outputStream, "  } for\n", 8);
      (*outputFunc)(outputStream, "def\n", 4);
    }
  }
  (*outputFunc)(outputStream, "/FontMatrix [1 0 0 1 0 0] def\n", 30);
  buf = GooString::format("/FontBBox [{0:d} {1:d} {2:d} {3:d}] def\n",
			bbox[0], bbox[1], bbox[2], bbox[3]);
  (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
  delete buf;
  (*outputFunc)(outputStream, "/PaintType 0 def\n", 17);
  (*outputFunc)(outputStream, "/Encoding [] readonly def\n", 26);
  (*outputFunc)(outputStream, "/CharStrings 1 dict dup begin\n", 30);
  (*outputFunc)(outputStream, "  /.notdef 0 def\n", 17);
  (*outputFunc)(outputStream, "  end readonly def\n", 19);

  // write the guts of the dictionary
  cvtSfnts(outputFunc, outputStream, nullptr, needVerticalMetrics, &maxUsedGlyph);

  // end the dictionary and define the font
  (*outputFunc)(outputStream,
		"CIDFontName currentdict end /CIDFont defineresource pop\n",
		56);
}

void FoFiTrueType::convertToCIDType0(const char *psName, int *cidMap, int nCIDs,
				     FoFiOutputFunc outputFunc,
				     void *outputStream) const {
  char *start;
  int length;
  FoFiType1C *ff;

  if (!getCFFBlock(&start, &length)) {
    return;
  }
  if (!(ff = FoFiType1C::make(start, length))) {
    return;
  }
  ff->convertToCIDType0(psName, cidMap, nCIDs, outputFunc, outputStream);
  delete ff;
}

void FoFiTrueType::convertToType0(const char *psName, int *cidMap, int nCIDs,
				  bool needVerticalMetrics,
				  int *maxValidGlyph,
				  FoFiOutputFunc outputFunc,
				  void *outputStream) const {
  GooString *buf;
  GooString *sfntsName;
  int maxUsedGlyph, n, i, j;

  *maxValidGlyph = -1;

  if (openTypeCFF) {
    return;
  }

  // write the Type 42 sfnts array
  sfntsName = (new GooString(psName))->append("_sfnts");
  cvtSfnts(outputFunc, outputStream, sfntsName, needVerticalMetrics,
	   &maxUsedGlyph);
  delete sfntsName;

  // write the descendant Type 42 fonts
  // (The following is a kludge: nGlyphs is the glyph count from the
  // maxp table; maxUsedGlyph is the max glyph number that has a
  // non-zero-length description, from the loca table.  The problem is
  // that some TrueType font subsets fail to change the glyph count,
  // i.e., nGlyphs is much larger than maxUsedGlyph+1, which results
  // in an unnecessarily huge Type 0 font.  But some other PDF files
  // have fonts with only zero or one used glyph, and a content stream
  // that refers to one of the unused glyphs -- this results in PS
  // errors if we simply use maxUsedGlyph+1 for the Type 0 font.  So
  // we compromise by always defining at least 256 glyphs.)
  // Some fonts have a large nGlyphs but maxUsedGlyph of 0.
  // These fonts might reference any glyph.
  // Return the last written glyph number in maxValidGlyph.
  // PSOutputDev::drawString() can use maxValidGlyph to avoid
  // referencing zero-length glyphs that we trimmed.
  // This allows pdftops to avoid writing huge files while still
  // handling the rare PDF that uses a zero-length glyph.
  if (cidMap) {
    n = nCIDs;
  } else if (nGlyphs > maxUsedGlyph + 256) {
    if (maxUsedGlyph <= 255) {
      n = 256;
    } else {
      n = maxUsedGlyph + 1;
    }
  } else {
    n = nGlyphs;
  }
  *maxValidGlyph = n-1;
  for (i = 0; i < n; i += 256) {
    (*outputFunc)(outputStream, "10 dict begin\n", 14);
    (*outputFunc)(outputStream, "/FontName /", 11);
    (*outputFunc)(outputStream, psName, strlen(psName));
    buf = GooString::format("_{0:02x} def\n", i >> 8);
    (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
    delete buf;
    (*outputFunc)(outputStream, "/FontType 42 def\n", 17);
    (*outputFunc)(outputStream, "/FontMatrix [1 0 0 1 0 0] def\n", 30);
    buf = GooString::format("/FontBBox [{0:d} {1:d} {2:d} {3:d}] def\n",
			  bbox[0], bbox[1], bbox[2], bbox[3]);
    (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
    delete buf;
    (*outputFunc)(outputStream, "/PaintType 0 def\n", 17);
    (*outputFunc)(outputStream, "/sfnts ", 7);
    (*outputFunc)(outputStream, psName, strlen(psName));
    (*outputFunc)(outputStream, "_sfnts def\n", 11);
    (*outputFunc)(outputStream, "/Encoding 256 array\n", 20);
    for (j = 0; j < 256 && i+j < n; ++j) {
      buf = GooString::format("dup {0:d} /c{1:02x} put\n", j, j);
      (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
      delete buf;
    }
    (*outputFunc)(outputStream, "readonly def\n", 13);
    (*outputFunc)(outputStream, "/CharStrings 257 dict dup begin\n", 32);
    (*outputFunc)(outputStream, "/.notdef 0 def\n", 15);
    for (j = 0; j < 256 && i+j < n; ++j) {
      buf = GooString::format("/c{0:02x} {1:d} def\n",
			    j, cidMap ? cidMap[i+j] : i+j);
      (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
      delete buf;
    }
    (*outputFunc)(outputStream, "end readonly def\n", 17);
    (*outputFunc)(outputStream,
		  "FontName currentdict end definefont pop\n", 40);
  }

  // write the Type 0 parent font
  (*outputFunc)(outputStream, "16 dict begin\n", 14);
  (*outputFunc)(outputStream, "/FontName /", 11);
  (*outputFunc)(outputStream, psName, strlen(psName));
  (*outputFunc)(outputStream, " def\n", 5);
  (*outputFunc)(outputStream, "/FontType 0 def\n", 16);
  (*outputFunc)(outputStream, "/FontMatrix [1 0 0 1 0 0] def\n", 30);
  (*outputFunc)(outputStream, "/FMapType 2 def\n", 16);
  (*outputFunc)(outputStream, "/Encoding [\n", 12);
  for (i = 0; i < n; i += 256) {
    buf = GooString::format("{0:d}\n", i >> 8);
    (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
    delete buf;
  }
  (*outputFunc)(outputStream, "] def\n", 6);
  (*outputFunc)(outputStream, "/FDepVector [\n", 14);
  for (i = 0; i < n; i += 256) {
    (*outputFunc)(outputStream, "/", 1);
    (*outputFunc)(outputStream, psName, strlen(psName));
    buf = GooString::format("_{0:02x} findfont\n", i >> 8);
    (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
    delete buf;
  }
  (*outputFunc)(outputStream, "] def\n", 6);
  (*outputFunc)(outputStream, "FontName currentdict end definefont pop\n", 40);
}

void FoFiTrueType::convertToType0(const char *psName, int *cidMap, int nCIDs,
				  FoFiOutputFunc outputFunc,
				  void *outputStream) const {
  char *start;
  int length;
  FoFiType1C *ff;

  if (!getCFFBlock(&start, &length)) {
    return;
  }
  if (!(ff = FoFiType1C::make(start, length))) {
    return;
  }
  ff->convertToType0(psName, cidMap, nCIDs, outputFunc, outputStream);
  delete ff;
}

void FoFiTrueType::cvtEncoding(char **encoding,
			       FoFiOutputFunc outputFunc,
			       void *outputStream) const {
  const char *name;
  GooString *buf;
  int i;

  (*outputFunc)(outputStream, "/Encoding 256 array\n", 20);
  if (encoding) {
    for (i = 0; i < 256; ++i) {
      if (!(name = encoding[i])) {
	name = ".notdef";
      }
      buf = GooString::format("dup {0:d} /", i);
      (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
      delete buf;
      (*outputFunc)(outputStream, name, strlen(name));
      (*outputFunc)(outputStream, " put\n", 5);
    }
  } else {
    for (i = 0; i < 256; ++i) {
      buf = GooString::format("dup {0:d} /c{1:02x} put\n", i, i);
      (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
      delete buf;
    }
  }
  (*outputFunc)(outputStream, "readonly def\n", 13);
}

void FoFiTrueType::cvtCharStrings(char **encoding,
				  int *codeToGID,
				  FoFiOutputFunc outputFunc,
				  void *outputStream) const {
  const char *name;
  GooString *buf;
  char buf2[16];
  int i, k;

  // always define '.notdef'
  (*outputFunc)(outputStream, "/CharStrings 256 dict dup begin\n", 32);
  (*outputFunc)(outputStream, "/.notdef 0 def\n", 15);

  // if there's no 'cmap' table, punt
  if (nCmaps == 0) {
    goto err;
  }

  // map char name to glyph index:
  // 1. use encoding to map name to char code
  // 2. use codeToGID to map char code to glyph index
  // N.B. We do this in reverse order because font subsets can have
  //      weird encodings that use the same character name twice, and
  //      the first definition is probably the one we want.
  k = 0; // make gcc happy
  for (i = 255; i >= 0; --i) {
    if (encoding) {
      name = encoding[i];
    } else {
      sprintf(buf2, "c%02x", i);
      name = buf2;
    }
    if (name && strcmp(name, ".notdef")) {
      k = codeToGID[i];
      // note: Distiller (maybe Adobe's PS interpreter in general)
      // doesn't like TrueType fonts that have CharStrings entries
      // which point to nonexistent glyphs, hence the (k < nGlyphs)
      // test
      if (k > 0 && k < nGlyphs) {
	(*outputFunc)(outputStream, "/", 1);
	(*outputFunc)(outputStream, name, strlen(name));
	buf = GooString::format(" {0:d} def\n", k);
	(*outputFunc)(outputStream, buf->c_str(), buf->getLength());
	delete buf;
      }
    }
  }

 err:
  (*outputFunc)(outputStream, "end readonly def\n", 17);
}

void FoFiTrueType::cvtSfnts(FoFiOutputFunc outputFunc,
			    void *outputStream, GooString *name,
			    bool needVerticalMetrics,
                            int *maxUsedGlyph) const {
  unsigned char headData[54];
  TrueTypeLoca *locaTable;
  unsigned char *locaData;
  TrueTypeTable newTables[nT42Tables];
  unsigned char tableDir[12 + nT42Tables*16];
  bool ok;
  unsigned int checksum;
  int nNewTables;
  int glyfTableLen, length, pos, glyfPos, i, j, k, vmtxTabLength;
  unsigned char vheaTab[36] = {
    0, 1, 0, 0,			// table version number
    0, 0,			// ascent
    0, 0,			// descent
    0, 0,			// reserved
    0, 0,			// max advance height
    0, 0,			// min top side bearing
    0, 0,			// min bottom side bearing
    0, 0,			// y max extent
    0, 0,			// caret slope rise
    0, 1,			// caret slope run
    0, 0,			// caret offset
    0, 0,			// reserved
    0, 0,			// reserved
    0, 0,			// reserved
    0, 0,			// reserved
    0, 0,			// metric data format
    0, 1			// number of advance heights in vmtx table
  };
  unsigned char *vmtxTab;
  bool needVhea, needVmtx;
  int advance;

  // construct the 'head' table, zero out the font checksum
  i = seekTable("head");
  if (i < 0 || i >= nTables) {
    return;
  }
  pos = tables[i].offset;
  if (!checkRegion(pos, 54)) {
    return;
  }
  memcpy(headData, file + pos, 54);
  headData[8] = headData[9] = headData[10] = headData[11] = (unsigned char)0;

  // check for a bogus loca format field in the 'head' table
  // (I've encountered fonts with loca format set to 0x0100 instead of 0x0001)
  if (locaFmt != 0 && locaFmt != 1) {
    headData[50] = 0;
    headData[51] = 1;
  }

  // read the original 'loca' table, pad entries out to 4 bytes, and
  // sort it into proper order -- some (non-compliant) fonts have
  // out-of-order loca tables; in order to correctly handle the case
  // where (compliant) fonts have empty entries in the middle of the
  // table, cmpTrueTypeLocaOffset uses offset as its primary sort key,
  // and idx as its secondary key (ensuring that adjacent entries with
  // the same pos value remain in the same order)
  locaTable = (TrueTypeLoca *)gmallocn(nGlyphs + 1, sizeof(TrueTypeLoca));
  i = seekTable("loca");
  pos = tables[i].offset;
  i = seekTable("glyf");
  glyfTableLen = tables[i].len;
  ok = true;
  for (i = 0; i <= nGlyphs; ++i) {
    locaTable[i].idx = i;
    if (locaFmt) {
      locaTable[i].origOffset = (int)getU32BE(pos + i*4, &ok);
    } else {
      locaTable[i].origOffset = 2 * getU16BE(pos + i*2, &ok);
    }
    if (locaTable[i].origOffset > glyfTableLen) {
      locaTable[i].origOffset = glyfTableLen;
    }
  }
  std::sort(locaTable, locaTable + nGlyphs + 1,
	    cmpTrueTypeLocaOffsetFunctor());
  for (i = 0; i < nGlyphs; ++i) {
    locaTable[i].len = locaTable[i+1].origOffset - locaTable[i].origOffset;
  }
  locaTable[nGlyphs].len = 0;
  std::sort(locaTable, locaTable + nGlyphs + 1, cmpTrueTypeLocaIdxFunctor());
  pos = 0;
  *maxUsedGlyph = -1;
  for (i = 0; i <= nGlyphs; ++i) {
    locaTable[i].newOffset = pos;
    pos += locaTable[i].len;
    if (pos & 3) {
      pos += 4 - (pos & 3);
    }
    if (locaTable[i].len > 0) {
      *maxUsedGlyph = i;
    }
  }

  // construct the new 'loca' table
  locaData = (unsigned char *)gmallocn(nGlyphs + 1, (locaFmt ? 4 : 2));
  for (i = 0; i <= nGlyphs; ++i) {
    pos = locaTable[i].newOffset;
    if (locaFmt) {
      locaData[4*i  ] = (unsigned char)(pos >> 24);
      locaData[4*i+1] = (unsigned char)(pos >> 16);
      locaData[4*i+2] = (unsigned char)(pos >>  8);
      locaData[4*i+3] = (unsigned char) pos;
    } else {
      locaData[2*i  ] = (unsigned char)(pos >> 9);
      locaData[2*i+1] = (unsigned char)(pos >> 1);
    }
  }

  // count the number of tables
  nNewTables = 0;
  for (i = 0; i < nT42Tables; ++i) {
    if (t42Tables[i].required ||
	seekTable(t42Tables[i].tag) >= 0) {
      ++nNewTables;
    }
  }
  vmtxTab = nullptr; // make gcc happy
  vmtxTabLength = 0;
  advance = 0; // make gcc happy
  if (needVerticalMetrics) {
    needVhea = seekTable("vhea") < 0;
    needVmtx = seekTable("vmtx") < 0;
    if (needVhea || needVmtx) {
      i = seekTable("head");
      advance = getU16BE(tables[i].offset + 18, &ok); // units per em
      if (needVhea) {
	++nNewTables;
      }
      if (needVmtx) {
	++nNewTables;
      }
    }
  }

  // construct the new table headers, including table checksums
  // (pad each table out to a multiple of 4 bytes)
  pos = 12 + nNewTables*16;
  k = 0;
  for (i = 0; i < nT42Tables; ++i) {
    length = -1;
    checksum = 0; // make gcc happy
    if (i == t42HeadTable) {
      length = 54;
      checksum = computeTableChecksum(headData, 54);
    } else if (i == t42LocaTable) {
      length = (nGlyphs + 1) * (locaFmt ? 4 : 2);
      checksum = computeTableChecksum(locaData, length);
    } else if (i == t42GlyfTable) {
      length = 0;
      checksum = 0;
      glyfPos = tables[seekTable("glyf")].offset;
      for (j = 0; j < nGlyphs; ++j) {
	length += locaTable[j].len;
	if (length & 3) {
	  length += 4 - (length & 3);
	}
	if (checkRegion(glyfPos + locaTable[j].origOffset, locaTable[j].len)) {
	  checksum +=
	      computeTableChecksum(file + glyfPos + locaTable[j].origOffset,
				   locaTable[j].len);
	}
      }
    } else {
      if ((j = seekTable(t42Tables[i].tag)) >= 0) {
	length = tables[j].len;
	if (checkRegion(tables[j].offset, length)) {
	  checksum = computeTableChecksum(file + tables[j].offset, length);
	}
      } else if (needVerticalMetrics && i == t42VheaTable) {
	vheaTab[10] = advance / 256;    // max advance height
	vheaTab[11] = advance % 256;
	length = sizeof(vheaTab);
	checksum = computeTableChecksum(vheaTab, length);
      } else if (needVerticalMetrics && i == t42VmtxTable) {
	length = 4 + (nGlyphs - 1) * 2;
	vmtxTabLength = length;
	vmtxTab = (unsigned char *)gmalloc(length);
	vmtxTab[0] = advance / 256;
	vmtxTab[1] = advance % 256;
	for (j = 2; j < length; j += 2) {
	  vmtxTab[j] = 0;
	  vmtxTab[j+1] = 0;
	}
	checksum = computeTableChecksum(vmtxTab, length);
      } else if (t42Tables[i].required) {
	//~ error(-1, "Embedded TrueType font is missing a required table ('%s')",
	//~       t42Tables[i].tag);
	length = 0;
	checksum = 0;
      }
    }
    if (length >= 0) {
      newTables[k].tag = ((t42Tables[i].tag[0] & 0xff) << 24) |
	                 ((t42Tables[i].tag[1] & 0xff) << 16) |
	                 ((t42Tables[i].tag[2] & 0xff) <<  8) |
	                  (t42Tables[i].tag[3] & 0xff);
      newTables[k].checksum = checksum;
      newTables[k].offset = pos;
      newTables[k].len = length;
      pos += length;
      if (pos & 3) {
	pos += 4 - (length & 3);
      }
      ++k;
    }
  }

  // construct the table directory
  tableDir[0] = 0x00;		// sfnt version
  tableDir[1] = 0x01;
  tableDir[2] = 0x00;
  tableDir[3] = 0x00;
  tableDir[4] = 0;		// numTables
  tableDir[5] = nNewTables;
  tableDir[6] = 0;		// searchRange
  tableDir[7] = (unsigned char)128;
  tableDir[8] = 0;		// entrySelector
  tableDir[9] = 3;
  tableDir[10] = 0;		// rangeShift
  tableDir[11] = (unsigned char)(16 * nNewTables - 128);
  pos = 12;
  for (i = 0; i < nNewTables; ++i) {
    tableDir[pos   ] = (unsigned char)(newTables[i].tag >> 24);
    tableDir[pos+ 1] = (unsigned char)(newTables[i].tag >> 16);
    tableDir[pos+ 2] = (unsigned char)(newTables[i].tag >>  8);
    tableDir[pos+ 3] = (unsigned char) newTables[i].tag;
    tableDir[pos+ 4] = (unsigned char)(newTables[i].checksum >> 24);
    tableDir[pos+ 5] = (unsigned char)(newTables[i].checksum >> 16);
    tableDir[pos+ 6] = (unsigned char)(newTables[i].checksum >>  8);
    tableDir[pos+ 7] = (unsigned char) newTables[i].checksum;
    tableDir[pos+ 8] = (unsigned char)(newTables[i].offset >> 24);
    tableDir[pos+ 9] = (unsigned char)(newTables[i].offset >> 16);
    tableDir[pos+10] = (unsigned char)(newTables[i].offset >>  8);
    tableDir[pos+11] = (unsigned char) newTables[i].offset;
    tableDir[pos+12] = (unsigned char)(newTables[i].len >> 24);
    tableDir[pos+13] = (unsigned char)(newTables[i].len >> 16);
    tableDir[pos+14] = (unsigned char)(newTables[i].len >>  8);
    tableDir[pos+15] = (unsigned char) newTables[i].len;
    pos += 16;
  }

  // compute the font checksum and store it in the head table
  checksum = computeTableChecksum(tableDir, 12 + nNewTables*16);
  for (i = 0; i < nNewTables; ++i) {
    checksum += newTables[i].checksum;
  }
  checksum = 0xb1b0afba - checksum; // because the TrueType spec says so
  headData[ 8] = (unsigned char)(checksum >> 24);
  headData[ 9] = (unsigned char)(checksum >> 16);
  headData[10] = (unsigned char)(checksum >>  8);
  headData[11] = (unsigned char) checksum;

  // start the sfnts array
  if (name) {
    (*outputFunc)(outputStream, "/", 1);
    (*outputFunc)(outputStream, name->c_str(), name->getLength());
    (*outputFunc)(outputStream, " [\n", 3);
  } else {
    (*outputFunc)(outputStream, "/sfnts [\n", 9);
  }

  // write the table directory
  dumpString(tableDir, 12 + nNewTables*16, outputFunc, outputStream);

  // write the tables
  for (i = 0; i < nNewTables; ++i) {
    if (i == t42HeadTable) {
      dumpString(headData, 54, outputFunc, outputStream);
    } else if (i == t42LocaTable) {
      length = (nGlyphs + 1) * (locaFmt ? 4 : 2);
      dumpString(locaData, length, outputFunc, outputStream);
    } else if (i == t42GlyfTable) {
      glyfPos = tables[seekTable("glyf")].offset;
      for (j = 0; j < nGlyphs; ++j) {
	if (locaTable[j].len > 0 &&
	    checkRegion(glyfPos + locaTable[j].origOffset, locaTable[j].len)) {
	  dumpString(file + glyfPos + locaTable[j].origOffset,
		     locaTable[j].len, outputFunc, outputStream);
	}
      }
    } else {
      // length == 0 means the table is missing and the error was
      // already reported during the construction of the table
      // headers
      if ((length = newTables[i].len) > 0) {
	if ((j = seekTable(t42Tables[i].tag)) >= 0 &&
	    checkRegion(tables[j].offset, tables[j].len)) {
	  dumpString(file + tables[j].offset, tables[j].len,
		     outputFunc, outputStream);
	} else if (needVerticalMetrics && i == t42VheaTable) {
	  if (unlikely(length > (int)sizeof(vheaTab))) {
	    error(errSyntaxWarning, -1, "length bigger than vheaTab size");
	    length = sizeof(vheaTab);
	  }
	  dumpString(vheaTab, length, outputFunc, outputStream);
	} else if (needVerticalMetrics && i == t42VmtxTable) {
	  if (unlikely(length > vmtxTabLength)) {
	    error(errSyntaxWarning, -1, "length bigger than vmtxTab size");
	    length = vmtxTabLength;
	  }
	  dumpString(vmtxTab, length, outputFunc, outputStream);
	}
      }
    }
  }

  // end the sfnts array
  (*outputFunc)(outputStream, "] def\n", 6);

  gfree(locaData);
  gfree(locaTable);
  if (vmtxTab) {
    gfree(vmtxTab);
  }
}

void FoFiTrueType::dumpString(const unsigned char *s, int length,
			      FoFiOutputFunc outputFunc,
			      void *outputStream) const {
  GooString *buf;
  int pad, i, j;

  (*outputFunc)(outputStream, "<", 1);
  for (i = 0; i < length; i += 32) {
    for (j = 0; j < 32 && i+j < length; ++j) {
      buf = GooString::format("{0:02x}", s[i+j] & 0xff);
      (*outputFunc)(outputStream, buf->c_str(), buf->getLength());
      delete buf;
    }
    if (i % (65536 - 32) == 65536 - 64) {
      (*outputFunc)(outputStream, ">\n<", 3);
    } else if (i+32 < length) {
      (*outputFunc)(outputStream, "\n", 1);
    }
  }
  if (length & 3) {
    pad = 4 - (length & 3);
    for (i = 0; i < pad; ++i) {
      (*outputFunc)(outputStream, "00", 2);
    }
  }
  // add an extra zero byte because the Adobe Type 42 spec says so
  (*outputFunc)(outputStream, "00>\n", 4);
}

unsigned int FoFiTrueType::computeTableChecksum(const unsigned char *data, int length) const {
  unsigned int checksum, word;
  int i;

  checksum = 0;
  for (i = 0; i+3 < length; i += 4) {
    word = ((data[i  ] & 0xff) << 24) +
           ((data[i+1] & 0xff) << 16) +
           ((data[i+2] & 0xff) <<  8) +
            (data[i+3] & 0xff);
    checksum += word;
  }
  if (length & 3) {
    word = 0;
    i = length & ~3;
    switch (length & 3) {
    case 3:
      word |= (data[i+2] & 0xff) <<  8;
      // fallthrough
    case 2:
      word |= (data[i+1] & 0xff) << 16;
      // fallthrough
    case 1:
      word |= (data[i  ] & 0xff) << 24;
      break;
    }
    checksum += word;
  }
  return checksum;
}

void FoFiTrueType::parse() {
  unsigned int topTag;
  int pos, ver, i, j;

  parsedOk = true;

  // look for a collection (TTC)
  topTag = getU32BE(0, &parsedOk);
  if (!parsedOk) {
    return;
  }
  if (topTag == ttcfTag) {
    /* TTC font */
    int dircount;

    dircount = getU32BE(8, &parsedOk);
    if (!parsedOk)
      return;
    if (! dircount) {
      parsedOk = false;
      return;
    }

    if (faceIndex >= dircount)
      faceIndex = 0;
    pos = getU32BE(12 + faceIndex * 4, &parsedOk);
    if (! parsedOk)
      return;
  } else {
    pos = 0;
  }

  // check the sfnt version
  ver = getU32BE(pos, &parsedOk);
  if (!parsedOk) {
    return;
  }
  openTypeCFF = ver == 0x4f54544f; // 'OTTO'

  // read the table directory
  nTables = getU16BE(pos + 4, &parsedOk);
  if (!parsedOk) {
    return;
  }
  tables = (TrueTypeTable *)gmallocn(nTables, sizeof(TrueTypeTable));
  pos += 12;
  j = 0;
  for (i = 0; i < nTables; ++i) {
    tables[j].tag = getU32BE(pos, &parsedOk);
    tables[j].checksum = getU32BE(pos + 4, &parsedOk);
    tables[j].offset = (int)getU32BE(pos + 8, &parsedOk);
    tables[j].len = (int)getU32BE(pos + 12, &parsedOk);
    if (unlikely((tables[j].offset < 0) ||
                 (tables[j].len < 0) ||
                 (tables[j].offset < INT_MAX - tables[j].len) ||
                 (tables[j].len > INT_MAX - tables[j].offset) ||
                 (tables[j].offset + tables[j].len >= tables[j].offset && tables[j].offset + tables[j].len <= len))) {
      // ignore any bogus entries in the table directory
      ++j;
    }
    pos += 16;
  }
  if (nTables != j) {
    nTables = j;
    tables = (TrueTypeTable *)greallocn_checkoverflow(tables, nTables, sizeof(TrueTypeTable));
  }
  if (!parsedOk || tables == nullptr) {
    return;
  }

  // check for tables that are required by both the TrueType spec and
  // the Type 42 spec
  if (seekTable("head") < 0 ||
      seekTable("hhea") < 0 ||
      seekTable("maxp") < 0 ||
      (!openTypeCFF && seekTable("loca") < 0) ||
      (!openTypeCFF && seekTable("glyf") < 0) ||
      (openTypeCFF && seekTable("CFF ") < 0)) {
    parsedOk = false;
    return;
  }

  // read the cmaps
  if ((i = seekTable("cmap")) >= 0) {
    pos = tables[i].offset + 2;
    nCmaps = getU16BE(pos, &parsedOk);
    pos += 2;
    if (!parsedOk) {
      return;
    }
    cmaps = (TrueTypeCmap *)gmallocn(nCmaps, sizeof(TrueTypeCmap));
    for (j = 0; j < nCmaps; ++j) {
      cmaps[j].platform = getU16BE(pos, &parsedOk);
      cmaps[j].encoding = getU16BE(pos + 2, &parsedOk);
      cmaps[j].offset = tables[i].offset + getU32BE(pos + 4, &parsedOk);
      pos += 8;
      cmaps[j].fmt = getU16BE(cmaps[j].offset, &parsedOk);
      cmaps[j].len = getU16BE(cmaps[j].offset + 2, &parsedOk);
    }
    if (!parsedOk) {
      return;
    }
  } else {
    nCmaps = 0;
  }

  // get the number of glyphs from the maxp table
  i = seekTable("maxp");
  nGlyphs = getU16BE(tables[i].offset + 4, &parsedOk);
  if (!parsedOk) {
    return;
  }

  // get the bbox and loca table format from the head table
  i = seekTable("head");
  bbox[0] = getS16BE(tables[i].offset + 36, &parsedOk);
  bbox[1] = getS16BE(tables[i].offset + 38, &parsedOk);
  bbox[2] = getS16BE(tables[i].offset + 40, &parsedOk);
  bbox[3] = getS16BE(tables[i].offset + 42, &parsedOk);
  locaFmt = getS16BE(tables[i].offset + 50, &parsedOk);
  if (!parsedOk) {
    return;
  }

  // read the post table
  readPostTable();
}

void FoFiTrueType::readPostTable() {
  std::string name;
  int tablePos, postFmt, stringIdx, stringPos;
  bool ok;
  int i, j, n, m;

  ok = true;
  if ((i = seekTable("post")) < 0) {
    return;
  }
  tablePos = tables[i].offset;
  postFmt = getU32BE(tablePos, &ok);
  if (!ok) {
    goto err;
  }
  if (postFmt == 0x00010000) {
    nameToGID.reserve(258);
    for (i = 0; i < 258; ++i) {
      nameToGID.emplace(macGlyphNames[i], i);
    }
  } else if (postFmt == 0x00020000) {
    nameToGID.reserve(258);
    n = getU16BE(tablePos + 32, &ok);
    if (!ok) {
      goto err;
    }
    if (n > nGlyphs) {
      n = nGlyphs;
    }
    stringIdx = 0;
    stringPos = tablePos + 34 + 2*n;
    for (i = 0; i < n; ++i) {
      ok = true;
      j = getU16BE(tablePos + 34 + 2*i, &ok);
      if (j < 258) {
	nameToGID[macGlyphNames[j]] = i;
      } else {
	j -= 258;
	if (j != stringIdx) {
	  for (stringIdx = 0, stringPos = tablePos + 34 + 2*n;
	       stringIdx < j;
	       ++stringIdx, stringPos += 1 + getU8(stringPos, &ok)) ;
	  if (!ok) {
	    continue;
	  }
	}
	m = getU8(stringPos, &ok);
	if (!ok || !checkRegion(stringPos + 1, m)) {
	  continue;
	}
	name.assign((char *)&file[stringPos + 1], m);
	nameToGID[name] = i;
	++stringIdx;
	stringPos += 1 + m;
      }
    }
  } else if (postFmt == 0x00028000) {
    nameToGID.reserve(258);
    for (i = 0; i < nGlyphs; ++i) {
      j = getU8(tablePos + 32 + i, &ok);
      if (!ok) {
	continue;
      }
      if (j < 258) {
	nameToGID[macGlyphNames[j]] = i;
      }
    }
  }

  return;

 err:
  nameToGID.clear();
}

int FoFiTrueType::seekTable(const char *tag) const {
  unsigned int tagI;
  int i;

  tagI = ((tag[0] & 0xff) << 24) |
         ((tag[1] & 0xff) << 16) |
         ((tag[2] & 0xff) << 8) |
          (tag[3] & 0xff);
  for (i = 0; i < nTables; ++i) {
    if (tables[i].tag == tagI) {
      return i;
    }
  }
  return -1;
}

unsigned int FoFiTrueType::charToTag(const char *tagName)
{
  int n = strlen(tagName);
  unsigned int tag = 0;
  int i;

  if (n > 4) n = 4;
  for (i = 0;i < n;i++) {
    tag <<= 8;
    tag |= tagName[i] & 0xff;
  }
  for (;i < 4;i++) {
    tag <<= 8;
    tag |= ' ';
  }
  return tag;
}

/*
  setup GSUB table data
  Only supporting vertical text substitution.
*/
int FoFiTrueType::setupGSUB(const char *scriptName)
{
  return setupGSUB(scriptName, nullptr);
}

/*
  setup GSUB table data
  Only supporting vertical text substitution.
*/
int FoFiTrueType::setupGSUB(const char *scriptName,
                            const char *languageName)
{
  unsigned int gsubTable;
  unsigned int i;
  unsigned int scriptList, featureList;
  unsigned int scriptCount;
  unsigned int tag;
  unsigned int scriptTable = 0;
  unsigned int langSys;
  unsigned int featureCount;
  unsigned int featureIndex;
  unsigned int ftable = 0;
  unsigned int llist;
  unsigned int scriptTag;
  int x;
  unsigned int pos;

  if (scriptName == nullptr) {
    gsubFeatureTable = 0;
    return 0;
  }
  scriptTag = charToTag(scriptName);
  /* read GSUB Header */
  if ((x = seekTable("GSUB")) < 0) {
    return 0; /* GSUB table not found */
  }
  gsubTable = tables[x].offset;
  pos = gsubTable+4;
  scriptList = getU16BE(pos,&parsedOk);
  pos += 2;
  featureList = getU16BE(pos,&parsedOk);
  pos += 2;
  llist = getU16BE(pos,&parsedOk);

  gsubLookupList = llist+gsubTable; /* change to offset from top of file */
  /* read script list table */
  pos = gsubTable+scriptList;
  scriptCount = getU16BE(pos,&parsedOk);
  pos += 2;
  /* find  script */
  for (i = 0;i < scriptCount;i++) {
    tag = getU32BE(pos,&parsedOk);
    pos += 4;
    scriptTable = getU16BE(pos,&parsedOk);
    pos += 2;
    if (tag == scriptTag) {
      /* found */
      break;
    }
  }
  if (i >= scriptCount) {
    /* not found */
    return 0;
  }

  /* read script table */
  /* use default language system */
  pos = gsubTable+scriptList+scriptTable;
  langSys = 0;
  if (languageName) {
    unsigned int langTag = charToTag(languageName);
    unsigned int langCount = getU16BE(pos+2,&parsedOk);
    for (i = 0;i < langCount && langSys == 0;i++) {
      tag = getU32BE(pos+4+i*(4+2),&parsedOk);
      if (tag == langTag) {
        langSys = getU16BE(pos+4+i*(4+2)+4,&parsedOk);
      }
    }
  }
  if (langSys == 0) {
    /* default language system */
    langSys = getU16BE(pos,&parsedOk);
  }

  /* read LangSys table */
  if (langSys == 0) {
    /* no default LangSys */
    return 0;
  }

  pos = gsubTable+scriptList+scriptTable+langSys+2;
  featureIndex = getU16BE(pos,&parsedOk); /* ReqFeatureIndex */
  pos += 2;

  if (featureIndex != 0xffff) {
    unsigned int tpos;
    /* read feature record */
    tpos = gsubTable+featureList;
    featureCount = getU16BE(tpos,&parsedOk);
    tpos = gsubTable+featureList+2+featureIndex*(4+2);
    tag = getU32BE(tpos,&parsedOk);
    tpos += 4;
    if (tag == vrt2Tag) {
      /* vrt2 is preferred, overwrite vert */
      ftable = getU16BE(tpos,&parsedOk);
      /* convert to offset from file top */
      gsubFeatureTable = ftable+gsubTable+featureList;
      return 0;
    } else if (tag == vertTag) {
      ftable = getU16BE(tpos,&parsedOk);
    }
  }
  featureCount = getU16BE(pos,&parsedOk);
  pos += 2;
  /* find 'vrt2' or 'vert' feature */
  for (i = 0;i < featureCount;i++) {
    unsigned int oldPos;

    featureIndex = getU16BE(pos,&parsedOk);
    pos += 2;
    oldPos = pos; /* save position */
    /* read feature record */
    pos = gsubTable+featureList+2+featureIndex*(4+2);
    tag = getU32BE(pos,&parsedOk);
    pos += 4;
    if (tag == vrt2Tag) {
      /* vrt2 is preferred, overwrite vert */
      ftable = getU16BE(pos,&parsedOk);
      break;
    } else if (ftable == 0 && tag == vertTag) {
      ftable = getU16BE(pos,&parsedOk);
    }
    pos = oldPos; /* restore old position */
  }
  if (ftable == 0) {
    /* vert nor vrt2 are not found */
    return 0;
  }
  /* convert to offset from file top */
  gsubFeatureTable = ftable+gsubTable+featureList;
  return 0;
}

unsigned int FoFiTrueType::doMapToVertGID(unsigned int orgGID)
{
  unsigned int lookupCount;
  unsigned int lookupListIndex;
  unsigned int i;
  unsigned int gid = 0;
  unsigned int pos;

  pos = gsubFeatureTable+2;
  lookupCount = getU16BE(pos,&parsedOk);
  pos += 2;
  for (i = 0;i < lookupCount;i++) {
    lookupListIndex = getU16BE(pos,&parsedOk);
    pos += 2;
    if ((gid = scanLookupList(lookupListIndex,orgGID)) != 0) {
      break;
    }
  }
  return gid;
}

unsigned int FoFiTrueType::mapToVertGID(unsigned int orgGID)
{
  unsigned int mapped;

  if (gsubFeatureTable == 0) return orgGID;
  if ((mapped = doMapToVertGID(orgGID)) != 0) {
    return mapped;
  }
  return orgGID;
}

unsigned int FoFiTrueType::scanLookupList(unsigned int listIndex, unsigned int orgGID)
{
  unsigned int lookupTable;
  unsigned int subTableCount;
  unsigned int subTable;
  unsigned int i;
  unsigned int gid = 0;
  unsigned int pos;

  if (gsubLookupList == 0) return 0; /* no lookup list */
  pos = gsubLookupList+2+listIndex*2;
  lookupTable = getU16BE(pos,&parsedOk);
  /* read lookup table */
  pos = gsubLookupList+lookupTable+4;
  subTableCount = getU16BE(pos,&parsedOk);
  pos += 2;;
  for (i = 0;i < subTableCount;i++) {
    subTable = getU16BE(pos,&parsedOk);
    pos += 2;
    if ((gid = scanLookupSubTable(gsubLookupList+lookupTable+subTable,orgGID))
         != 0) break;
  }
  return gid;
}

unsigned int FoFiTrueType::scanLookupSubTable(unsigned int subTable, unsigned int orgGID)
{
  unsigned int format;
  unsigned int coverage;
  int delta;
  int glyphCount;
  unsigned int substitute;
  unsigned int gid = 0;
  int coverageIndex;
  int pos;

  pos = subTable;
  format = getU16BE(pos,&parsedOk);
  pos += 2;
  coverage = getU16BE(pos,&parsedOk);
  pos += 2;
  if ((coverageIndex =
     checkGIDInCoverage(subTable+coverage,orgGID)) >= 0) {
    switch (format) {
    case 1:
      /* format 1 */
      delta = getS16BE(pos,&parsedOk);
      pos += 2;
      gid = orgGID+delta;
      break;
    case 2:
      /* format 2 */
      glyphCount = getS16BE(pos,&parsedOk);
      pos += 2;
      if (glyphCount > coverageIndex) {
	pos += coverageIndex*2;
	substitute = getU16BE(pos,&parsedOk);
        gid = substitute;
      }
      break;
    default:
      /* unknown format */
      break;
    }
  }
  return gid;
}

int FoFiTrueType::checkGIDInCoverage(unsigned int coverage, unsigned int orgGID)
{
  int index = -1;
  unsigned int format;
  unsigned int count;
  unsigned int i;
  unsigned int pos;

  pos = coverage;
  format = getU16BE(pos,&parsedOk);
  pos += 2;
  switch (format) {
  case 1:
    count = getU16BE(pos,&parsedOk);
    pos += 2;
    // In some poor CJK fonts, key GIDs are not sorted,
    // thus we cannot finish checking even when the range
    // including orgGID seems to have already passed.
    for (i = 0;i < count;i++) {
      unsigned int gid;

      gid = getU16BE(pos,&parsedOk);
      pos += 2;
      if (gid == orgGID) {
        /* found */
        index = i;
        break;
      }
    }
    break;
  case 2:
    count = getU16BE(pos,&parsedOk);
    pos += 2;
    for (i = 0;i < count;i++) {
      unsigned int startGID, endGID;
      unsigned int startIndex;

      startGID = getU16BE(pos,&parsedOk);
      pos += 2;
      endGID = getU16BE(pos,&parsedOk);
      pos += 2;
      startIndex = getU16BE(pos,&parsedOk);
      pos += 2;
      // In some poor CJK fonts, key GIDs are not sorted,
      // thus we cannot finish checking even when the range
      // including orgGID seems to have already passed.
      if (startGID <= orgGID && orgGID <= endGID) {
        /* found */
        index = startIndex+orgGID-startGID;
        break;
      }
    }
    break;
  default:
    break;
  }
  return index;
}