class TTF:
def __init__(self, path):
with open(path, "rb") as f:
self.src = f.read()
self.header = Header(self.src)
self.offsetData = 12 + 16 * self.header.numTables
self.tables = OrderedDict()
for i in range(self.header.numTables):
idx = 12 + 16 * i
t = Table(self.src, idx)
self.tables[t.tag] = t
if t.tag == "loca":
print binascii.b2a_hex(t.data[-3])
# sort tables with offset
# self.tables.sort(key=lambda x: x.offset)
# get global properties
head = self.tables["head"]
self.checkSumAdjustment = struct.unpack("!L", head.data[8:12])[0]
head.data = head.data[:8] + "\0\0\0\0" + head.data[12:]
# byte length of loca values
loca = self.tables["loca"]
if (ord(head.data[-1]) & 0xFF) >> 4 == 0:
loca_format = "H"
loca_size = 2
else:
loca_format = "L"
loca_size = 4
self.numGlyphs = struct.unpack("!H", self.tables["maxp"].data[4:6])[0]
print "loca_format: ", loca_format
print "len(self.loca.data): ", len(loca.data)
print "numGlyphs: ", self.numGlyphs
glyf_offsets = struct.unpack("!" + str(self.numGlyphs + 1) + loca_format, loca.data)
print "len(glyf_offsets): ", len(glyf_offsets)
# check checksum for all table
def checkTables(self):
for k,t in self.tables.items():
tmp = t.data
if k == "head":
tmp = tmp[:8] + "\0\0\0\0" + tmp[12:]
if t.checkSum == calcSum(tmp):
print k, ": ok"
else:
print k, ": ng"
# dump table for debug
def dumpTable(self, name):
if not(name in self.tables):
return
with open(name + "_data", "wb") as f:
f.write(self.tables[k].data)
def outputTTF(self):
ttf_header = ""
ttf_table = ""
ttf_data = ""
# make sure tables are sorted by offset
# self.tables.sort(key=lambda x: x.offset)
# compute offsets for data
offset_new = 0
# offset for ttf_data = len(ttf_header + ttf_table)
offset_data = 12 + (16 * self.header.numTables)
# for checkSumAdj
offset_csa = 0
totalSum = 0
# FIRST: generate ttf_data, and calculate offset
offsets = {}
for k, t in sorted(self.tables.items(), key=lambda x: x[1].offset):
offsets[k] = offset_new
ttf_data += t.data
# insert paddings
if t.length % 4 != 0:
ttf_data += "\0" * (4 - (t.length % 4))
# check the data with src
left = offset_data + offset_new
if (self.src[left : left + t.length] == t.data and
ttf_data[offset_new : offset_new + t.length] == t.data):
print k, ": same"
else:
print k, ": different"
# for checkSumAdjustment.
totalSum += t.checkSum
# update offset, including paddings
offset_new += (t.length + 3) & 0xFFFFFFFC
# SECOND: generate ttf_table
for k,t in self.tables.items():
t.offset = offsets[k] + offset_data
ttf_table += t.outputTTF()
# THIRD: generate ttf_header
ttf_header = self.header.outputTTF()
# now we gotta calculate checkSumAdjustment in head table.
offset_csa = offsets["head"] + 8
if ttf_data[offset_csa:offset_csa+4] == "\0\0\0\0":
print "csa is \\0\\0\\0\\0, it's ok!"
num_int32 = (12 + (16 * self.header.numTables)) / 4
totalSum += sum(struct.unpack("!" + str(num_int32) + "L", ttf_header + ttf_table))
csa_old = self.src[offset_data + offset_csa : offset_data + offset_csa + 4]
csa = (0xB1B0AFBA - totalSum) & 0xFFFFFFFF
print "old csa: ", binascii.b2a_hex(csa_old)
print "new csa: ", binascii.b2a_hex(struct.pack("!L", csa))
ttf_data = ttf_data[:offset_csa] + struct.pack("!L", csa) + ttf_data[(offset_csa+4):]
head = self.tables["head"]
left = head.offset + offset_data
if self.src[left : left + head.length] == head.data:
print "head: same"
else:
print "head: different"
# check values with self.src
if ttf_header == self.src[:12]:
print "header: same"
else:
print "header: different"
if ttf_table == self.src[12:12+(16*self.header.numTables)]:
print "table: same"
else:
print "table: different"
if ttf_data == self.src[12+(16*self.header.numTables):]:
print "data: same"
else:
print "data: different"
s = (ttf_header + ttf_table + ttf_data)
if s == self.src:
print "all same!!!"
else:
print "all differ..."
return s
def glitch(self):
pass
