Source code for fontTools.t1Lib

"""fontTools.t1Lib.py -- Tools for PostScript Type 1 fonts (Python2 only)

Functions for reading and writing raw Type 1 data:

read(path)
	reads any Type 1 font file, returns the raw data and a type indicator:
	'LWFN', 'PFB' or 'OTHER', depending on the format of the file pointed
	to by 'path'.
	Raises an error when the file does not contain valid Type 1 data.

write(path, data, kind='OTHER', dohex=False)
	writes raw Type 1 data to the file pointed to by 'path'.
	'kind' can be one of 'LWFN', 'PFB' or 'OTHER'; it defaults to 'OTHER'.
	'dohex' is a flag which determines whether the eexec encrypted
	part should be written as hexadecimal or binary, but only if kind
	is 'OTHER'.
"""
import fontTools
from fontTools.misc import eexec
from fontTools.misc.macCreatorType import getMacCreatorAndType
from fontTools.misc.textTools import bytechr, byteord, bytesjoin, tobytes
from fontTools.misc.psOperators import _type1_pre_eexec_order, _type1_fontinfo_order, _type1_post_eexec_order
from fontTools.encodings.StandardEncoding import StandardEncoding
import os
import re

__author__ = "jvr"
__version__ = "1.0b3"
DEBUG = 0


try:
	try:
		from Carbon import Res
	except ImportError:
		import Res  # MacPython < 2.2
except ImportError:
	haveMacSupport = 0
else:
	haveMacSupport = 1


[docs]class T1Error(Exception): pass
[docs]class T1Font(object): """Type 1 font class. Uses a minimal interpeter that supports just about enough PS to parse Type 1 fonts. """ def __init__(self, path, encoding="ascii", kind=None): if kind is None: self.data, _ = read(path) elif kind == "LWFN": self.data = readLWFN(path) elif kind == "PFB": self.data = readPFB(path) elif kind == "OTHER": self.data = readOther(path) else: raise ValueError(kind) self.encoding = encoding
[docs] def saveAs(self, path, type, dohex=False): write(path, self.getData(), type, dohex)
[docs] def getData(self): if not hasattr(self, "data"): self.data = self.createData() return self.data
[docs] def getGlyphSet(self): """Return a generic GlyphSet, which is a dict-like object mapping glyph names to glyph objects. The returned glyph objects have a .draw() method that supports the Pen protocol, and will have an attribute named 'width', but only *after* the .draw() method has been called. In the case of Type 1, the GlyphSet is simply the CharStrings dict. """ return self["CharStrings"]
def __getitem__(self, key): if not hasattr(self, "font"): self.parse() return self.font[key]
[docs] def parse(self): from fontTools.misc import psLib from fontTools.misc import psCharStrings self.font = psLib.suckfont(self.data, self.encoding) charStrings = self.font["CharStrings"] lenIV = self.font["Private"].get("lenIV", 4) assert lenIV >= 0 subrs = self.font["Private"]["Subrs"] for glyphName, charString in charStrings.items(): charString, R = eexec.decrypt(charString, 4330) charStrings[glyphName] = psCharStrings.T1CharString(charString[lenIV:], subrs=subrs) for i in range(len(subrs)): charString, R = eexec.decrypt(subrs[i], 4330) subrs[i] = psCharStrings.T1CharString(charString[lenIV:], subrs=subrs) del self.data
[docs] def createData(self): sf = self.font eexec_began = False eexec_dict = {} lines = [] lines.extend([self._tobytes(f"%!FontType1-1.1: {sf['FontName']}"), self._tobytes(f"%t1Font: ({fontTools.version})"), self._tobytes(f"%%BeginResource: font {sf['FontName']}")]) # follow t1write.c:writeRegNameKeyedFont size = 3 # Headroom for new key addition size += 1 # FontMatrix is always counted size += 1 + 1 # Private, CharStings for key in font_dictionary_keys: size += int(key in sf) lines.append(self._tobytes(f"{size} dict dup begin")) for key, value in sf.items(): if eexec_began: eexec_dict[key] = value continue if key == "FontInfo": fi = sf["FontInfo"] # follow t1write.c:writeFontInfoDict size = 3 # Headroom for new key addition for subkey in FontInfo_dictionary_keys: size += int(subkey in fi) lines.append(self._tobytes(f"/FontInfo {size} dict dup begin")) for subkey, subvalue in fi.items(): lines.extend(self._make_lines(subkey, subvalue)) lines.append(b"end def") elif key in _type1_post_eexec_order: # usually 'Private' eexec_dict[key] = value eexec_began = True else: lines.extend(self._make_lines(key, value)) lines.append(b"end") eexec_portion = self.encode_eexec(eexec_dict) lines.append(bytesjoin([b"currentfile eexec ", eexec_portion])) for _ in range(8): lines.append(self._tobytes("0"*64)) lines.extend([b"cleartomark", b"%%EndResource", b"%%EOF"]) data = bytesjoin(lines, "\n") return data
[docs] def encode_eexec(self, eexec_dict): lines = [] # '-|', '|-', '|' RD_key, ND_key, NP_key = None, None, None for key, value in eexec_dict.items(): if key == "Private": pr = eexec_dict["Private"] # follow t1write.c:writePrivateDict size = 3 # for RD, ND, NP for subkey in Private_dictionary_keys: size += int(subkey in pr) lines.append(b"dup /Private") lines.append(self._tobytes(f"{size} dict dup begin")) for subkey, subvalue in pr.items(): if not RD_key and subvalue == RD_value: RD_key = subkey elif not ND_key and subvalue == ND_value: ND_key = subkey elif not NP_key and subvalue == PD_value: NP_key = subkey if subkey == 'OtherSubrs': # XXX: assert that no flex hint is used lines.append(self._tobytes(hintothers)) elif subkey == "Subrs": # XXX: standard Subrs only lines.append(b"/Subrs 5 array") for i, subr_bin in enumerate(std_subrs): encrypted_subr, R = eexec.encrypt(bytesjoin([char_IV, subr_bin]), 4330) lines.append(bytesjoin([self._tobytes(f"dup {i} {len(encrypted_subr)} {RD_key} "), encrypted_subr, self._tobytes(f" {NP_key}")])) lines.append(b'def') lines.append(b"put") else: lines.extend(self._make_lines(subkey, subvalue)) elif key == "CharStrings": lines.append(b"dup /CharStrings") lines.append(self._tobytes(f"{len(eexec_dict['CharStrings'])} dict dup begin")) for glyph_name, char_bin in eexec_dict["CharStrings"].items(): char_bin.compile() encrypted_char, R = eexec.encrypt(bytesjoin([char_IV, char_bin.bytecode]), 4330) lines.append(bytesjoin([self._tobytes(f"/{glyph_name} {len(encrypted_char)} {RD_key} "), encrypted_char, self._tobytes(f" {ND_key}")])) lines.append(b"end put") else: lines.extend(self._make_lines(key, value)) lines.extend([b"end", b"dup /FontName get exch definefont pop", b"mark", b"currentfile closefile\n"]) eexec_portion = bytesjoin(lines, "\n") encrypted_eexec, R = eexec.encrypt(bytesjoin([eexec_IV, eexec_portion]), 55665) return encrypted_eexec
def _make_lines(self, key, value): if key == "FontName": return [self._tobytes(f"/{key} /{value} def")] if key in ["isFixedPitch", "ForceBold", "RndStemUp"]: return [self._tobytes(f"/{key} {'true' if value else 'false'} def")] elif key == "Encoding": if value == StandardEncoding: return [self._tobytes(f"/{key} StandardEncoding def")] else: # follow fontTools.misc.psOperators._type1_Encoding_repr lines = [] lines.append(b"/Encoding 256 array") lines.append(b"0 1 255 {1 index exch /.notdef put} for") for i in range(256): name = value[i] if name != ".notdef": lines.append(self._tobytes(f"dup {i} /{name} put")) lines.append(b"def") return lines if isinstance(value, str): return [self._tobytes(f"/{key} ({value}) def")] elif isinstance(value, bool): return [self._tobytes(f"/{key} {'true' if value else 'false'} def")] elif isinstance(value, list): return [self._tobytes(f"/{key} [{' '.join(str(v) for v in value)}] def")] elif isinstance(value, tuple): return [self._tobytes(f"/{key} {{{' '.join(str(v) for v in value)}}} def")] else: return [self._tobytes(f"/{key} {value} def")] def _tobytes(self, s, errors="strict"): return tobytes(s, self.encoding, errors)
# low level T1 data read and write functions
[docs]def read(path, onlyHeader=False): """reads any Type 1 font file, returns raw data""" _, ext = os.path.splitext(path) ext = ext.lower() creator, typ = getMacCreatorAndType(path) if typ == 'LWFN': return readLWFN(path, onlyHeader), 'LWFN' if ext == '.pfb': return readPFB(path, onlyHeader), 'PFB' else: return readOther(path), 'OTHER'
[docs]def write(path, data, kind='OTHER', dohex=False): assertType1(data) kind = kind.upper() try: os.remove(path) except os.error: pass err = 1 try: if kind == 'LWFN': writeLWFN(path, data) elif kind == 'PFB': writePFB(path, data) else: writeOther(path, data, dohex) err = 0 finally: if err and not DEBUG: try: os.remove(path) except os.error: pass
# -- internal -- LWFNCHUNKSIZE = 2000 HEXLINELENGTH = 80
[docs]def readLWFN(path, onlyHeader=False): """reads an LWFN font file, returns raw data""" from fontTools.misc.macRes import ResourceReader reader = ResourceReader(path) try: data = [] for res in reader.get('POST', []): code = byteord(res.data[0]) if byteord(res.data[1]) != 0: raise T1Error('corrupt LWFN file') if code in [1, 2]: if onlyHeader and code == 2: break data.append(res.data[2:]) elif code in [3, 5]: break elif code == 4: with open(path, "rb") as f: data.append(f.read()) elif code == 0: pass # comment, ignore else: raise T1Error('bad chunk code: ' + repr(code)) finally: reader.close() data = bytesjoin(data) assertType1(data) return data
[docs]def readPFB(path, onlyHeader=False): """reads a PFB font file, returns raw data""" data = [] with open(path, "rb") as f: while True: if f.read(1) != bytechr(128): raise T1Error('corrupt PFB file') code = byteord(f.read(1)) if code in [1, 2]: chunklen = stringToLong(f.read(4)) chunk = f.read(chunklen) assert len(chunk) == chunklen data.append(chunk) elif code == 3: break else: raise T1Error('bad chunk code: ' + repr(code)) if onlyHeader: break data = bytesjoin(data) assertType1(data) return data
[docs]def readOther(path): """reads any (font) file, returns raw data""" with open(path, "rb") as f: data = f.read() assertType1(data) chunks = findEncryptedChunks(data) data = [] for isEncrypted, chunk in chunks: if isEncrypted and isHex(chunk[:4]): data.append(deHexString(chunk)) else: data.append(chunk) return bytesjoin(data)
# file writing tools
[docs]def writeLWFN(path, data): # Res.FSpCreateResFile was deprecated in OS X 10.5 Res.FSpCreateResFile(path, "just", "LWFN", 0) resRef = Res.FSOpenResFile(path, 2) # write-only try: Res.UseResFile(resRef) resID = 501 chunks = findEncryptedChunks(data) for isEncrypted, chunk in chunks: if isEncrypted: code = 2 else: code = 1 while chunk: res = Res.Resource(bytechr(code) + '\0' + chunk[:LWFNCHUNKSIZE - 2]) res.AddResource('POST', resID, '') chunk = chunk[LWFNCHUNKSIZE - 2:] resID = resID + 1 res = Res.Resource(bytechr(5) + '\0') res.AddResource('POST', resID, '') finally: Res.CloseResFile(resRef)
[docs]def writePFB(path, data): chunks = findEncryptedChunks(data) with open(path, "wb") as f: for isEncrypted, chunk in chunks: if isEncrypted: code = 2 else: code = 1 f.write(bytechr(128) + bytechr(code)) f.write(longToString(len(chunk))) f.write(chunk) f.write(bytechr(128) + bytechr(3))
[docs]def writeOther(path, data, dohex=False): chunks = findEncryptedChunks(data) with open(path, "wb") as f: hexlinelen = HEXLINELENGTH // 2 for isEncrypted, chunk in chunks: if isEncrypted: code = 2 else: code = 1 if code == 2 and dohex: while chunk: f.write(eexec.hexString(chunk[:hexlinelen])) f.write(b'\r') chunk = chunk[hexlinelen:] else: f.write(chunk)
# decryption tools EEXECBEGIN = b"currentfile eexec" # The spec allows for 512 ASCII zeros interrupted by arbitrary whitespace to # follow eexec EEXECEND = re.compile(b'(0[ \t\r\n]*){512}', flags=re.M) EEXECINTERNALEND = b"currentfile closefile" EEXECBEGINMARKER = b"%-- eexec start\r" EEXECENDMARKER = b"%-- eexec end\r" _ishexRE = re.compile(b'[0-9A-Fa-f]*$')
[docs]def isHex(text): return _ishexRE.match(text) is not None
[docs]def decryptType1(data): chunks = findEncryptedChunks(data) data = [] for isEncrypted, chunk in chunks: if isEncrypted: if isHex(chunk[:4]): chunk = deHexString(chunk) decrypted, R = eexec.decrypt(chunk, 55665) decrypted = decrypted[4:] if decrypted[-len(EEXECINTERNALEND)-1:-1] != EEXECINTERNALEND \ and decrypted[-len(EEXECINTERNALEND)-2:-2] != EEXECINTERNALEND: raise T1Error("invalid end of eexec part") decrypted = decrypted[:-len(EEXECINTERNALEND)-2] + b'\r' data.append(EEXECBEGINMARKER + decrypted + EEXECENDMARKER) else: if chunk[-len(EEXECBEGIN)-1:-1] == EEXECBEGIN: data.append(chunk[:-len(EEXECBEGIN)-1]) else: data.append(chunk) return bytesjoin(data)
[docs]def findEncryptedChunks(data): chunks = [] while True: eBegin = data.find(EEXECBEGIN) if eBegin < 0: break eBegin = eBegin + len(EEXECBEGIN) + 1 endMatch = EEXECEND.search(data, eBegin) if endMatch is None: raise T1Error("can't find end of eexec part") eEnd = endMatch.start() cypherText = data[eBegin:eEnd + 2] if isHex(cypherText[:4]): cypherText = deHexString(cypherText) plainText, R = eexec.decrypt(cypherText, 55665) eEndLocal = plainText.find(EEXECINTERNALEND) if eEndLocal < 0: raise T1Error("can't find end of eexec part") chunks.append((0, data[:eBegin])) chunks.append((1, cypherText[:eEndLocal + len(EEXECINTERNALEND) + 1])) data = data[eEnd:] chunks.append((0, data)) return chunks
[docs]def deHexString(hexstring): return eexec.deHexString(bytesjoin(hexstring.split()))
# Type 1 assertion _fontType1RE = re.compile(br"/FontType\s+1\s+def")
[docs]def assertType1(data): for head in [b'%!PS-AdobeFont', b'%!FontType1']: if data[:len(head)] == head: break else: raise T1Error("not a PostScript font") if not _fontType1RE.search(data): raise T1Error("not a Type 1 font") if data.find(b"currentfile eexec") < 0: raise T1Error("not an encrypted Type 1 font") # XXX what else? return data
# pfb helpers
[docs]def longToString(long): s = b"" for i in range(4): s += bytechr((long & (0xff << (i * 8))) >> i * 8) return s
[docs]def stringToLong(s): if len(s) != 4: raise ValueError('string must be 4 bytes long') l = 0 for i in range(4): l += byteord(s[i]) << (i * 8) return l
# PS stream helpers font_dictionary_keys = list(_type1_pre_eexec_order) # t1write.c:writeRegNameKeyedFont # always counts following keys font_dictionary_keys.remove("FontMatrix") FontInfo_dictionary_keys = list(_type1_fontinfo_order) # extend because AFDKO tx may use following keys FontInfo_dictionary_keys.extend([ "FSType", "Copyright", ]) Private_dictionary_keys = [ # We don't know what names will be actually used. # "RD", # "ND", # "NP", "Subrs", "OtherSubrs", "UniqueID", "BlueValues", "OtherBlues", "FamilyBlues", "FamilyOtherBlues", "BlueScale", "BlueShift", "BlueFuzz", "StdHW", "StdVW", "StemSnapH", "StemSnapV", "ForceBold", "LanguageGroup", "password", "lenIV", "MinFeature", "RndStemUp", ] # t1write_hintothers.h hintothers = """/OtherSubrs[{}{}{}{systemdict/internaldict known not{pop 3}{1183615869 systemdict/internaldict get exec dup/startlock known{/startlock get exec}{dup /strtlck known{/strtlck get exec}{pop 3}ifelse}ifelse}ifelse}executeonly]def""" # t1write.c:saveStdSubrs std_subrs = [ # 3 0 callother pop pop setcurrentpoint return b"\x8e\x8b\x0c\x10\x0c\x11\x0c\x11\x0c\x21\x0b", # 0 1 callother return b"\x8b\x8c\x0c\x10\x0b", # 0 2 callother return b"\x8b\x8d\x0c\x10\x0b", # return b"\x0b", # 3 1 3 callother pop callsubr return b"\x8e\x8c\x8e\x0c\x10\x0c\x11\x0a\x0b" ] # follow t1write.c:writeRegNameKeyedFont eexec_IV = b"cccc" char_IV = b"\x0c\x0c\x0c\x0c" RD_value = ("string", "currentfile", "exch", "readstring", "pop") ND_value = ("def",) PD_value = ("put",)