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"""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'.
"""
from fontTools.misc.py23 import bytechr, byteord, bytesjoin
from fontTools.misc import eexec
from fontTools.misc.macCreatorType import getMacCreatorAndType
import os
import re
__author__ = "jvr"
__version__ = "1.0b2"
DEBUG = 0
try:
try:
from Carbon import Res
except ImportError:
import Res # MacPython < 2.2
except ImportError:
haveMacSupport = 0
else:
haveMacSupport = 1
class T1Error(Exception): pass
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
def saveAs(self, path, type, dohex=False):
write(path, self.getData(), type, dohex)
def getData(self):
# XXX Todo: if the data has been converted to Python object,
# recreate the PS stream
return self.data
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]
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
# low level T1 data read and write functions
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'
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
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
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
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
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)
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))
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]*$')
def isHex(text):
return _ishexRE.match(text) is not None
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)
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
def deHexString(hexstring):
return eexec.deHexString(bytesjoin(hexstring.split()))
# Type 1 assertion
_fontType1RE = re.compile(br"/FontType\s+1\s+def")
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
def longToString(long):
s = b""
for i in range(4):
s += bytechr((long & (0xff << (i * 8))) >> i * 8)
return s
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