/* * This dictionary hold the decoded fonts */ var Fonts = new Dict(); var Base64Encoder = { encode: function(aData) { var str = []; var count = aData.length; for (var i = 0; i < count; i++) str.push(aData.getChar()); return window.btoa(str.join("")); } }; var TrueTypeFont = function(aFontName, aFontFile) { if (Fonts.get(aFontName)) return; //log("Loading a TrueType font: " + aFontName); var fontData = Base64Encoder.encode(aFontFile); Fonts.set(aFontName, fontData); // Add the css rule var url = "url(data:font/ttf;base64," + fontData + ");"; document.styleSheets[0].insertRule("@font-face { font-family: '" + aFontName + "'; src: " + url + " }", 0); }; var Type1Parser = function(aAsciiStream, aBinaryStream) { var lexer = new Lexer(aAsciiStream); // Turn on this flag for additional debugging logs var debug = false; var dump = function(aData) { if (debug) log(aData); }; /* * Parse a whole Type1 font stream (from the first segment to the last) * assuming the 'eexec' block is binary data and fill up the 'Fonts' * dictionary with the font informations. */ var self = this; this.parse = function() { if (!debug) { while (!processNextToken()) {}; } else { // debug mode is used to debug postcript processing setTimeout(function() { if (!processNextToken()) self.parse(); }, 0); } } /* * Decrypt a Sequence of Ciphertext Bytes to Produce the Original Sequence * of Plaintext Bytes. The function took a key as a parameter which can be * for decrypting the eexec block of for decoding charStrings. */ var kEexecEncryptionKey = 55665; var kCharStringsEncryptionKey = 4330; function decrypt(aStream, aKey, aDiscardNumber) { var start = Date.now(); var r = aKey, c1 = 52845, c2 = 22719; var decryptedString = []; var value = ""; var count = aStream.length; for (var i = 0; i < count; i++) { value = aStream.getByte(); decryptedString[i] = String.fromCharCode(value ^ (r >> 8)); r = ((value + r) * c1 + c2) & ((1 << 16) - 1); } var end = Date.now(); dump("Time to decrypt string of length " + count + " is " + (end - start)); return decryptedString.slice(aDiscardNumber); } /* * CharStrings are encoded following the the CharString Encoding sequence * describe in Chapter 6 of the "Adobe Type1 Font Format" specification. * The value in a byte indicates a command, a number, or subsequent bytes * that are to be interpreted in a special way. * * CharString Number Encoding: * A CharString byte containing the values from 32 through 255 inclusive * indicate an integer. These values are decoded in four ranges. * * 1. A CharString byte containing a value, v, between 32 and 246 inclusive, * indicate the integer v - 139. Thus, the integer values from -107 through * 107 inclusive may be encoded in single byte. * * 2. A CharString byte containing a value, v, between 247 and 250 inclusive, * indicates an integer involving the next byte, w, according to the formula: * [(v - 247) x 256] + w + 108 * * 3. A CharString byte containing a value, v, between 251 and 254 inclusive, * indicates an integer involving the next byte, w, according to the formula: * -[(v - 251) * 256] - w - 108 * * 4. A CharString containing the value 255 indicates that the next 4 bytes * are a two complement signed integer. The first of these bytes contains the * highest order bits, the second byte contains the next higher order bits * and the fourth byte contain the lowest order bits. * * * CharString Command Encoding: * CharStrings commands are encoded in 1 or 2 bytes. * * Single byte commands are encoded in 1 byte that contains a value between * 0 and 31 inclusive. * If a command byte contains the value 12, then the value in the next byte * indicates a command. This "escape" mechanism allows many extra commands * to be encoded and this encoding technique helps to minimize the length of * the charStrings. */ var charStringDictionary = { "1": "hstem", "3": "vstem", "4": "vmoveto", "5": "rlineto", "6": "hlineto", "7": "vlineto", "8": "rrcurveto", "9": "closepath", "10": "callsubr", "11": "return", "12": { "0": "dotsection", "1": "vstem3", "3": "hstem3", "6": "seac", "7": "sbw", "12": "div", "16": "callothersubr", "17": "pop", "33": "setcurrentpoint" }, "13": "hsbw", "14": "endchar", "21": "rmoveto", "22": "hmoveto", "30": "vhcurveto", "31": "hcurveto" }; // XXX Is count++ the right thing to do? Is it not i++? function decodeCharString(aStream) { var start = Date.now(); var charString = []; var value = ""; var count = aStream.length; for (var i = 0; i < count; i++) { value = aStream.getByte(); if (value < 0) { continue; } else if (value < 32) { if (value == 12) { value = charStringDictionary["12"][aStream.getByte()]; count++; } else { value = charStringDictionary[value]; } } else if (value <= 246) { value = parseInt(value) - 139; } else if (value <= 250) { value = ((value - 247) * 256) + parseInt(aStream.getByte()) + 108; count++; } else if (value <= 254) { value = -((value - 251) * 256) - parseInt(aStream.getByte()) - 108; count++; } else { var byte = aStream.getByte(); var high = (byte >> 1); value = (byte - high) << 24 | aStream.getByte() << 16 | aStream.getByte() << 8 | aStream.getByte(); count += 4; } charString.push(value); } var end = Date.now(); dump("Time to decode charString of length " + count + " is " + (end - start)); return charString; } /* * The operand stack holds arbitrary PostScript objects that are the operands * and results of PostScript operators being executed. The interpreter pushes * objects on the operand stack when it encounters them as literal data in a * program being executed. When an operator requires one or more operands, it * obtains them by popping them off the top of the operand stack. When an * operator returns one or more results, it does so by pushing them on the * operand stack. */ var operandStack = { __innerStack__: [], push: function(aOperand) { this.__innerStack__.push(aOperand); }, pop: function() { if (!this.length) throw new Error("stackunderflow"); return this.__innerStack__.pop(); }, peek: function() { if (!this.length) return null; return this.__innerStack__[this.__innerStack__.length - 1]; }, dump: function() { log("=== Start Dumping operandStack ==="); var str = []; for (var i = 0; i < this.length; i++) log(this.__innerStack__[i]); log("=== End Dumping operandStack ==="); }, get length() { return this.__innerStack__.length; } }; // Flag indicating if the topmost operand of the operandStack is an array var operandIsArray = 0; /* * The dictionary stack holds only dictionary objects. The current set of * dictionaries on the dictionary stack defines the environment for all * implicit name searches, such as those that occur when the interpreter * encounters an executable name. The role of the dictionary stack is * introduced in Section 3.3, “Data Types and Objects,” and is further * explained in Section 3.5, “Execution.” of the PostScript Language * Reference. */ var systemDict = new Dict(), globalDict = new Dict(), userDict = new Dict(); var dictionaryStack = { __innerStack__: [systemDict, globalDict, userDict], push: function(aDictionary) { this.__innerStack__.push(aDictionary); }, pop: function() { if (this.__innerStack__.length == 3) return null; return this.__innerStack__.pop(); }, peek: function() { if (!this.length) return null; return this.__innerStack__[this.__innerStack__.length - 1]; }, get: function(aIndex) { return this.__innerStack__[aIndex]; }, get length() { return this.__innerStack__.length; }, dump: function() { log("=== Start Dumping dictionaryStack ==="); var str = []; for (var i = 0; i < this.length; i++) log(this.__innerStack__[i]); log("=== End Dumping dictionaryStack ==="); }, }; /* * The execution stack holds executable objects (mainly procedures and files) * that are in intermediate stages of execution. At any point in the * execution of a PostScript program, this stack represents the program’s * call stack. Whenever the interpreter suspends execution of an object to * execute some other object, it pushes the new object on the execution * stack. When the interpreter finishes executing an object, it pops that * object off the execution stack and resumes executing the suspended object * beneath it. */ var executionStack = { __innerStack__: [], push: function(aProcedure) { this.__innerStack__.push(aProcedure); }, pop: function() { return this.__innerStack__.pop(); }, peek: function() { if (!this.length) return null; return this.__innerStack__[this.__innerStack__.length - 1]; }, get: function(aIndex) { return this.__innerStack__[aIndex]; }, get length() { return this.__innerStack__.length; } }; /* * Return the next token in the execution stack */ function nextInStack() { var currentProcedure = executionStack.peek(); if (currentProcedure) { var command = currentProcedure.shift(); if (!currentProcedure.length) executionStack.pop(); return command; } return lexer.getObj(); }; /* * Get the next token from the executionStack and process it. * Actually the function does not process the third segment of a Type1 font * and end on 'closefile'. * * The method thrown an error if it encounters an unknown token. */ function processNextToken() { var obj = nextInStack(); if (operandIsArray && !IsCmd(obj, "{") && !IsCmd(obj, "[") && !IsCmd(obj, "]") && !IsCmd(obj, "}")) { dump("Adding an object: " + obj +" to array " + operandIsArray); var currentArray = operandStack.peek(); for (var i = 1; i < operandIsArray; i++) currentArray = currentArray[currentArray.length - 1]; currentArray.push(obj); } else if (IsBool(obj) || IsInt(obj) || IsNum(obj) || IsString(obj)) { dump("Value: " + obj); operandStack.push(obj); } else if (IsName(obj)) { dump("Name: " + obj.name); operandStack.push(obj.name); } else if (IsCmd(obj)) { var command = obj.cmd; dump(command); switch (command) { case "[": case "{": dump("Start" + (command == "{" ? " Executable " : " ") + "Array"); operandIsArray++; var currentArray = operandStack; for (var i = 1; i < operandIsArray; i++) if (currentArray.peek) currentArray = currentArray.peek(); else currentArray = currentArray[currentArray.length - 1]; currentArray.push([]); break; case "]": case "}": var currentArray = operandStack.peek(); for (var i = 1; i < operandIsArray; i++) currentArray = currentArray[currentArray.length - 1]; dump("End" + (command == "}" ? " Executable " : " ") + "Array: " + currentArray.join(" ")); operandIsArray--; break; case "if": var procedure = operandStack.pop(); var bool = operandStack.pop(); if (!IsBool(bool)) { dump("if: " + bool); // we need to execute things, let be dirty executionStack.push(bool); } else { dump("if ( " + bool + " ) { " + procedure + " }"); if (bool) executionStack.push(procedure); } break; case "ifelse": var procedure1 = operandStack.pop(); var procedure2 = operandStack.pop(); var bool = !!operandStack.pop(); dump("if ( " + bool + " ) { " + procedure2 + " } else { " + procedure1 + " }"); executionStack.push(bool ? procedure2 : procedure1); break; case "for": var procedure = operandStack.pop(); var limit = operandStack.pop(); var increment = operandStack.pop(); var initial = operandStack.pop(); for (var i = 0; i < limit; i += increment) { operandStack.push(i); executionStack.push(procedure.slice()); } break; case "dup": dump("duplicate: " + operandStack.peek()); operandStack.push(operandStack.peek()); break; case "mark": operandStack.push("mark"); break; case "cleartomark": var command = ""; do { command = operandStack.pop(); } while (command != "mark"); break; case "put": var data = operandStack.pop(); var indexOrKey = operandStack.pop(); var object = operandStack.pop(); dump("put " + data + " in " + object + "[" + indexOrKey + "]"); object.set ? object.set(indexOrKey, data) : object[indexOrKey] = data; break; case "pop": operandStack.pop(); break; case "exch": var operand1 = operandStack.pop(); var operand2 = operandStack.pop(); operandStack.push(operand1); operandStack.push(operand2); break; case "get": var indexOrKey = operandStack.pop(); var object = operandStack.pop(); var data = object.get ? object.get(indexOrKey) : object[indexOrKey]; dump("get " + object + "[" + indexOrKey + "]: " + data); operandStack.push(data); break; case "currentdict": var dict = dictionaryStack.peek(); operandStack.push(dict); break; case "systemdict": operandStack.push(systemDict); break; case "readonly": case "executeonly": case "noaccess": // Do nothing for the moment break; case "currentfile": operandStack.push("currentfile"); break; case "array": var size = operandStack.pop(); var array = new Array(size); operandStack.push(array); break; case "dict": var size = operandStack.pop(); var dict = new Dict(size); operandStack.push(dict); break; case "begin": dictionaryStack.push(operandStack.pop()); break; case "end": dictionaryStack.pop(); break; case "def": var value = operandStack.pop(); var key = operandStack.pop(); // XXX we don't want to do that here but for some reasons the names // are different between what is declared and the FontName directive if (key == "FontName" && Fonts.get(value)) { // The font has already be decoded, stop! return true; } dump("def: " + key + " = " + value); dictionaryStack.peek().set(key, value); break; case "definefont": var font = operandStack.pop(); var key = operandStack.pop(); dump("definefont " + font + " with key: " + key); Fonts.set(key, font); operandStack.push(font); break; case "known": var name = operandStack.pop(); var dict = operandStack.pop(); var data = !!dict.get(name); dump("known: " + data + " :: " + name + " in dict: " + dict); operandStack.push(data); break; case "exec": executionStack.push(operandStack.pop()); break; case "eexec": // All the first segment data has been read, decrypt the second segment // and start interpreting it in order to decode it var file = operandStack.pop(); var eexecString = decrypt(aBinaryStream, kEexecEncryptionKey, 4).join(""); dump(eexecString); lexer = new Lexer(new StringStream(eexecString)); break; case "LenIV": error("LenIV: argh! we need to modify the length of discard characters for charStrings"); break; case "closefile": var file = operandStack.pop(); return true; break; case "index": var operands = []; var size = operandStack.pop(); for (var i = 0; i < size; i++) operands.push(operandStack.pop()); var newOperand = operandStack.peek(); while (operands.length) operandStack.push(operands.pop()); operandStack.push(newOperand); break; case "string": var size = operandStack.pop(); var str = (new Array(size + 1)).join(" "); operandStack.push(str); break; case "readstring": var str = operandStack.pop(); var size = str.length; var file = operandStack.pop(); // Add '1' because of the space separator, this is dirty var stream = lexer.stream.makeSubStream(lexer.stream.pos + 1, size); lexer.stream.skip(size + 1); var charString = decrypt(stream, kCharStringsEncryptionKey, 4).join(""); var charStream = new StringStream(charString); var decodedCharString = decodeCharString(charStream); dump("decodedCharString: " + decodedCharString); operandStack.push(decodedCharString); // boolean indicating if the operation is a success or not operandStack.push(true); break; case "StandardEncoding": // For some reason the value is considered as a command, maybe it is // because of the uppercase 'S' operandStack.push(obj.cmd); break; default: var command = null; if (IsCmd(obj)) { for (var i = 0; i < dictionaryStack.length; i++) { if (command = dictionaryStack.get(i).get(obj.cmd)) { dump("found in dictionnary for " + obj.cmd + " command: " + command); executionStack.push(command.slice()); break; } } } if (!command) { log("operandStack: " + operandStack); log("dictionaryStack: " + dictionaryStack); log(obj); error("Unknow command while parsing font"); } break; } } else if (obj){ dump("unknow: " + obj); operandStack.push(obj); } return false; } }; var type1hack = false; var Type1Font = function(aFontName, aFontFile) { // All Type1 font program should begin with the comment %! if (aFontFile.getByte() != 0x25 || aFontFile.getByte() != 0x21) error("Invalid file header"); if (!type1hack) { type1hack= true; var start = Date.now(); var ASCIIStream = aFontFile.makeSubStream(0, aFontFile.dict.get("Length1"), aFontFile.dict); var binaryStream = aFontFile.makeSubStream(aFontFile.dict.get("Length1"), aFontFile.dict.get("Length2"), aFontFile.dict); this.parser = new Type1Parser(ASCIIStream, binaryStream); this.parser.parse(); var end = Date.now(); //log("Time to parse font is:" + (end - start)); this.convert(); } }; /** * The Type2 reader code below is only used for debugging purpose since Type2 * is only a CharString format and is never used directly as a Font file. * * So the code here is useful for dumping the data content of a .cff file in * order to investigate the similarity between a Type1 CharString and a Type2 * CharString. */ /** * Build a charset by assigning the glyph name and the human readable form * of the glyph data. */ function readCharset(aStream, aCharstrings) { var charset = {}; var format = aStream.getByte(); if (format == 0) { charset[".notdef"] = readCharstringEncoding(aCharstrings[0]); var count = aCharstrings.length - 1; for (var i = 1; i < count + 1; i++) { var sid = aStream.getByte() << 8 | aStream.getByte(); charset[CFFStrings[sid]] = readCharstringEncoding(aCharstrings[i]); log(CFFStrings[sid] + "::" + charset[CFFStrings[sid]]); } } else if (format == 1) { error("Charset Range are not supported"); } else { error("Invalid charset format"); } return charset; }; /** * Take a Type2 binary charstring as input and transform it to a human * readable representation as specified by the 'The Type 2 Charstring Format', * chapter 3.1. */ function readCharstringEncoding(aString) { var charstringTokens = []; var count = aString.length; for (var i = 0; i < count; ) { var value = aString[i++]; var token = null; if (value < 0) { continue; } else if (value <= 11) { token = CFFEncodingMap[value]; } else if (value == 12) { token = CFFEncodingMap[value][aString[i++]]; } else if (value <= 18) { token = CFFEncodingMap[value]; } else if (value <= 20) { var mask = aString[i++]; token = CFFEncodingMap[value]; } else if (value <= 27) { token = CFFEncodingMap[value]; } else if (value == 28) { token = aString[i++] << 8 | aString[i++]; } else if (value <= 31) { token = CFFEncodingMap[value]; } else if (value < 247) { token = parseInt(value) - 139; } else if (value < 251) { token = ((value - 247) * 256) + aString[i++] + 108; } else if (value < 255) { token = -((value - 251) * 256) - aString[i++] - 108; } else {// value == 255 token = aString[i++] << 24 | aString[i++] << 16 | aString[i++] << 8 | aString[i]; } charstringTokens.push(token); } return charstringTokens; }; /** * Take a binary DICT Data as input and transform it into a human readable * form as specified by 'The Compact Font Format Specification', chapter 5. */ function readFontDictData(aString, aMap) { var fontDictDataTokens = []; var count = aString.length; for (var i = 0; i < count; i) { var value = aString[i++]; var token = null; if (value == 12) { token = aMap[value][aString[i++]]; } else if (value == 28) { token = aString[i++] << 8 | aString[i++]; } else if (value == 29) { token = aString[i++] << 24 | aString[i++] << 16 | aString[i++] << 8 | aString[i++]; } else if (value == 30) { token = ""; var parsed = false; while (!parsed) { var byte = aString[i++]; var nibbles = [parseInt(byte / 16), parseInt(byte % 16)]; for (var j = 0; j < nibbles.length; j++) { var nibble = nibbles[j]; switch (nibble) { case 0xA: token += "."; break; case 0xB: token += "E"; break; case 0xC: token += "E-"; break; case 0xD: break; case 0xE: token += "-"; break; case 0xF: parsed = true; break; default: token += nibble; break; } } }; token = parseFloat(token); } else if (value <= 31) { token = aMap[value]; } else if (value <= 246) { token = parseInt(value) - 139; } else if (value <= 250) { token = ((value - 247) * 256) + aString[i++] + 108; } else if (value <= 254) { token = -((value - 251) * 256) - aString[i++] - 108; } else if (value == 255) { error("255 is not a valid DICT command"); } fontDictDataTokens.push(token); } return fontDictDataTokens; }; /** * Take a stream as input and return an array of objects. * In CFF an INDEX is a structure with the following format: * { * count: 2 bytes (Number of objects stored in INDEX), * offsize: 1 byte (Offset array element size), * offset: [count + 1] bytes (Offsets array), * data: - (Objects data) * } * * More explanation are given in the 'CFF Font Format Specification', * chapter 5. */ function readFontIndexData(aStream, aIsByte) { var count = aStream.getByte() << 8 | aStream.getByte(); var offsize = aStream.getByte(); function getNextOffset() { switch (offsize) { case 0: return 0; case 1: return aStream.getByte(); case 2: return aStream.getByte() << 8 | aStream.getByte(); case 3: return aStream.getByte() << 16 | aStream.getByte() << 8 | aStream.getByte(); case 4: return aStream.getByte() << 24 | aStream.getByte() << 16 | aStream.getByte() << 8 | aStream.getByte(); } }; var offsets = []; for (var i = 0; i < count + 1; i++) offsets.push(getNextOffset()); log("Found " + count + " objects at offsets :" + offsets + " (offsize: " + offsize + ")"); // Now extract the objects var relativeOffset = aStream.pos; var objects = []; for (var i = 0; i < count; i++) { var offset = offsets[i]; aStream.pos = relativeOffset + offset - 1; var data = []; var length = offsets[i + 1] - 1; for (var j = offset - 1; j < length; j++) data.push(aIsByte ? aStream.getByte() : aStream.getChar()); objects.push(data); } return objects; }; var Type2Parser = function(aFilePath) { var font = new Dict(); // Turn on this flag for additional debugging logs var debug = true; function dump(aStr) { if (debug) log(aStr); }; function parseAsToken(aString, aMap) { var decoded = readFontDictData(aString, aMap); log(decoded); var stack = []; var count = decoded.length; for (var i = 0; i < count; i++) { var token = decoded[i]; if (IsNum(token)) { stack.push(token); } else { switch (token.operand) { case "SID": font.set(token.name, CFFStrings[stack.pop()]); break; case "number number": font.set(token.name, { offset: stack.pop(), size: stack.pop() }); break; case "boolean": font.set(token.name, stack.pop()); break; case "delta": font.set(token.name, stack.pop()); break; default: if (token.operand && token.operand.length) { var array = []; for (var j = 0; j < token.operand.length; j++) array.push(stack.pop()); font.set(token.name, array); } else { font.set(token.name, stack.pop()); } break; } } } }; this.parse = function(aStream) { font.set("major", aStream.getByte()); font.set("minor", aStream.getByte()); font.set("hdrSize", aStream.getByte()); font.set("offsize", aStream.getByte()); // Move the cursor after the header aStream.skip(font.get("hdrSize") - aStream.pos); // Read the NAME Index dump("Reading Index: Names"); font.set("Names", readFontIndexData(aStream)); // Read the Top Dict Index dump("Reading Index: TopDict"); var topDict = readFontIndexData(aStream, true); // Read the String Index dump("Reading Index: Strings"); var strings = readFontIndexData(aStream); // Fill up the Strings dictionary with the new unique strings for (var i = 0; i < strings.length; i++) CFFStrings.push(strings[i].join("")); // Parse the TopDict operator var objects = []; var count = topDict.length; for (var i = 0; i < count; i++) parseAsToken(topDict[i], CFFDictDataMap); // Read the Global Subr Index that comes just after the Strings Index // (cf. "The Compact Font Format Specification" Chapter 16) dump("Reading Global Subr Index"); var subrs = readFontIndexData(aStream); // Reading Private Dict var private = font.get("Private"); log("Reading Private Dict (offset: " + private.offset + " size: " + private.size + ")"); aStream.pos = private.offset; var privateDict = []; for (var i = 0; i < private.size; i++) privateDict.push(aStream.getByte()); parseAsToken(privateDict, CFFDictPrivateDataMap); for (var p in font.map) dump(p + "::" + font.get(p)); // Read CharStrings Index var charStringsOffset = font.get("CharStrings"); dump("Read CharStrings Index (offset: " + charStringsOffset + ")"); aStream.pos = charStringsOffset; var charStrings = readFontIndexData(aStream, true); var charsetEntry = font.get("charset"); if (charsetEntry == 0) { throw new Error("Need to support CFFISOAdobeCharset"); } else if (charsetEntry == 1) { throw new Error("Need to support CFFExpert"); } else if (charsetEntry == 2) { throw new Error("Need to support CFFExpertSubsetCharset"); } else { aStream.pos = charsetEntry; var charset = readCharset(aStream, charStrings); } } }; // XXX var xhr = new XMLHttpRequest(); xhr.open("GET", "titi.cff", false); xhr.mozResponseType = xhr.responseType = "arraybuffer"; xhr.expected = (document.URL.indexOf("file:") == 0) ? 0 : 200; xhr.send(null); var cffData = xhr.mozResponseArrayBuffer || xhr.mozResponse || xhr.responseArrayBuffer || xhr.response; var cff = new Type2Parser("titi.cff"); cff.parse(new Stream(cffData));