[cffLib] Move desubroutinize code to new cffLib.transforms module

This commit is contained in:
Behdad Esfahbod 2024-05-21 12:34:28 -07:00
parent 65cc8bfb3c
commit a851d02519
2 changed files with 118 additions and 115 deletions

View File

@ -45,93 +45,6 @@ maxStackLimit = 513
# maxstack operator has been deprecated. max stack is now always 513. # maxstack operator has been deprecated. max stack is now always 513.
class StopHintCountEvent(Exception):
pass
class _DesubroutinizingT2Decompiler(psCharStrings.SimpleT2Decompiler):
stop_hintcount_ops = (
"op_hintmask",
"op_cntrmask",
"op_rmoveto",
"op_hmoveto",
"op_vmoveto",
)
def __init__(self, localSubrs, globalSubrs, private=None):
psCharStrings.SimpleT2Decompiler.__init__(
self, localSubrs, globalSubrs, private
)
def execute(self, charString):
self.need_hintcount = True # until proven otherwise
for op_name in self.stop_hintcount_ops:
setattr(self, op_name, self.stop_hint_count)
if hasattr(charString, "_desubroutinized"):
# If a charstring has already been desubroutinized, we will still
# need to execute it if we need to count hints in order to
# compute the byte length for mask arguments, and haven't finished
# counting hints pairs.
if self.need_hintcount and self.callingStack:
try:
psCharStrings.SimpleT2Decompiler.execute(self, charString)
except StopHintCountEvent:
del self.callingStack[-1]
return
charString._patches = []
psCharStrings.SimpleT2Decompiler.execute(self, charString)
desubroutinized = charString.program[:]
for idx, expansion in reversed(charString._patches):
assert idx >= 2
assert desubroutinized[idx - 1] in [
"callsubr",
"callgsubr",
], desubroutinized[idx - 1]
assert type(desubroutinized[idx - 2]) == int
if expansion[-1] == "return":
expansion = expansion[:-1]
desubroutinized[idx - 2 : idx] = expansion
if not self.private.in_cff2:
if "endchar" in desubroutinized:
# Cut off after first endchar
desubroutinized = desubroutinized[
: desubroutinized.index("endchar") + 1
]
charString._desubroutinized = desubroutinized
del charString._patches
def op_callsubr(self, index):
subr = self.localSubrs[self.operandStack[-1] + self.localBias]
psCharStrings.SimpleT2Decompiler.op_callsubr(self, index)
self.processSubr(index, subr)
def op_callgsubr(self, index):
subr = self.globalSubrs[self.operandStack[-1] + self.globalBias]
psCharStrings.SimpleT2Decompiler.op_callgsubr(self, index)
self.processSubr(index, subr)
def stop_hint_count(self, *args):
self.need_hintcount = False
for op_name in self.stop_hintcount_ops:
setattr(self, op_name, None)
cs = self.callingStack[-1]
if hasattr(cs, "_desubroutinized"):
raise StopHintCountEvent()
def op_hintmask(self, index):
psCharStrings.SimpleT2Decompiler.op_hintmask(self, index)
if self.need_hintcount:
self.stop_hint_count()
def processSubr(self, index, subr):
cs = self.callingStack[-1]
if not hasattr(cs, "_desubroutinized"):
cs._patches.append((index, subr._desubroutinized))
class CFFFontSet(object): class CFFFontSet(object):
"""A CFF font "file" can contain more than one font, although this is """A CFF font "file" can contain more than one font, although this is
extremely rare (and not allowed within OpenType fonts). extremely rare (and not allowed within OpenType fonts).
@ -396,34 +309,9 @@ class CFFFontSet(object):
_convertCFF2ToCFF(self, otFont) _convertCFF2ToCFF(self, otFont)
def desubroutinize(self): def desubroutinize(self):
for fontName in self.fontNames: from .transforms import desubroutinize
font = self[fontName]
cs = font.CharStrings desubroutinize(self)
for c in cs.values():
c.decompile()
subrs = getattr(c.private, "Subrs", [])
decompiler = _DesubroutinizingT2Decompiler(
subrs, c.globalSubrs, c.private
)
decompiler.execute(c)
c.program = c._desubroutinized
del c._desubroutinized
# Delete all the local subrs
if hasattr(font, "FDArray"):
for fd in font.FDArray:
pd = fd.Private
if hasattr(pd, "Subrs"):
del pd.Subrs
if "Subrs" in pd.rawDict:
del pd.rawDict["Subrs"]
else:
pd = font.Private
if hasattr(pd, "Subrs"):
del pd.Subrs
if "Subrs" in pd.rawDict:
del pd.rawDict["Subrs"]
# as well as the global subrs
self.GlobalSubrs.clear()
class CFFWriter(object): class CFFWriter(object):

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@ -0,0 +1,115 @@
from fontTools.misc.psCharStrings import SimpleT2Decompiler
class StopHintCountEvent(Exception):
pass
class _DesubroutinizingT2Decompiler(SimpleT2Decompiler):
stop_hintcount_ops = (
"op_hintmask",
"op_cntrmask",
"op_rmoveto",
"op_hmoveto",
"op_vmoveto",
)
def __init__(self, localSubrs, globalSubrs, private=None):
SimpleT2Decompiler.__init__(self, localSubrs, globalSubrs, private)
def execute(self, charString):
self.need_hintcount = True # until proven otherwise
for op_name in self.stop_hintcount_ops:
setattr(self, op_name, self.stop_hint_count)
if hasattr(charString, "_desubroutinized"):
# If a charstring has already been desubroutinized, we will still
# need to execute it if we need to count hints in order to
# compute the byte length for mask arguments, and haven't finished
# counting hints pairs.
if self.need_hintcount and self.callingStack:
try:
SimpleT2Decompiler.execute(self, charString)
except StopHintCountEvent:
del self.callingStack[-1]
return
charString._patches = []
SimpleT2Decompiler.execute(self, charString)
desubroutinized = charString.program[:]
for idx, expansion in reversed(charString._patches):
assert idx >= 2
assert desubroutinized[idx - 1] in [
"callsubr",
"callgsubr",
], desubroutinized[idx - 1]
assert type(desubroutinized[idx - 2]) == int
if expansion[-1] == "return":
expansion = expansion[:-1]
desubroutinized[idx - 2 : idx] = expansion
if not self.private.in_cff2:
if "endchar" in desubroutinized:
# Cut off after first endchar
desubroutinized = desubroutinized[
: desubroutinized.index("endchar") + 1
]
charString._desubroutinized = desubroutinized
del charString._patches
def op_callsubr(self, index):
subr = self.localSubrs[self.operandStack[-1] + self.localBias]
SimpleT2Decompiler.op_callsubr(self, index)
self.processSubr(index, subr)
def op_callgsubr(self, index):
subr = self.globalSubrs[self.operandStack[-1] + self.globalBias]
SimpleT2Decompiler.op_callgsubr(self, index)
self.processSubr(index, subr)
def stop_hint_count(self, *args):
self.need_hintcount = False
for op_name in self.stop_hintcount_ops:
setattr(self, op_name, None)
cs = self.callingStack[-1]
if hasattr(cs, "_desubroutinized"):
raise StopHintCountEvent()
def op_hintmask(self, index):
SimpleT2Decompiler.op_hintmask(self, index)
if self.need_hintcount:
self.stop_hint_count()
def processSubr(self, index, subr):
cs = self.callingStack[-1]
if not hasattr(cs, "_desubroutinized"):
cs._patches.append((index, subr._desubroutinized))
def desubroutinize(cff):
for fontName in cff.fontNames:
font = cff[fontName]
cs = font.CharStrings
for c in cs.values():
c.decompile()
subrs = getattr(c.private, "Subrs", [])
decompiler = _DesubroutinizingT2Decompiler(subrs, c.globalSubrs, c.private)
decompiler.execute(c)
c.program = c._desubroutinized
del c._desubroutinized
# Delete all the local subrs
if hasattr(font, "FDArray"):
for fd in font.FDArray:
pd = fd.Private
if hasattr(pd, "Subrs"):
del pd.Subrs
if "Subrs" in pd.rawDict:
del pd.rawDict["Subrs"]
else:
pd = font.Private
if hasattr(pd, "Subrs"):
del pd.Subrs
if "Subrs" in pd.rawDict:
del pd.rawDict["Subrs"]
# as well as the global subrs
cff.GlobalSubrs.clear()