ALINA_KURBANOVA/AIM-PIbd-32-Kurbanova-A-A
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity
d82b74e2e8
AIM-PIbd-32-Kurbanova-A-A/aimenv/Lib/site-packages/fontTools/ttLib/tables/otBase.py

1466 lines
52 KiB
Python
Raw Normal View History

lab 1 is done
2024-10-02 22:15:59 +04:00
from fontTools.config import OPTIONS
from fontTools.misc.textTools import Tag, bytesjoin
from .DefaultTable import DefaultTable
from enum import IntEnum
import sys
import array
import struct
import logging
from functools import lru_cache
from typing import Iterator, NamedTuple, Optional, Tuple
log = logging.getLogger(__name__)
have_uharfbuzz = False
try:
import uharfbuzz as hb
# repack method added in uharfbuzz >= 0.23; if uharfbuzz *can* be
# imported but repack method is missing, behave as if uharfbuzz
# is not available (fallback to the slower Python implementation)
have_uharfbuzz = callable(getattr(hb, "repack", None))
except ImportError:
pass
USE_HARFBUZZ_REPACKER = OPTIONS[f"{__name__}:USE_HARFBUZZ_REPACKER"]
class OverflowErrorRecord(object):
def __init__(self, overflowTuple):
self.tableType = overflowTuple[0]
self.LookupListIndex = overflowTuple[1]
self.SubTableIndex = overflowTuple[2]
self.itemName = overflowTuple[3]
self.itemIndex = overflowTuple[4]
def __repr__(self):
return str(
(
self.tableType,
"LookupIndex:",
self.LookupListIndex,
"SubTableIndex:",
self.SubTableIndex,
"ItemName:",
self.itemName,
"ItemIndex:",
self.itemIndex,
)
)
class OTLOffsetOverflowError(Exception):
def __init__(self, overflowErrorRecord):
self.value = overflowErrorRecord
def __str__(self):
return repr(self.value)
class RepackerState(IntEnum):
# Repacking control flow is implemnted using a state machine. The state machine table:
#
# State | Packing Success | Packing Failed | Exception Raised |
# ------------+-----------------+----------------+------------------+
# PURE_FT | Return result | PURE_FT | Return failure |
# HB_FT | Return result | HB_FT | FT_FALLBACK |
# FT_FALLBACK | HB_FT | FT_FALLBACK | Return failure |
# Pack only with fontTools, don't allow sharing between extensions.
PURE_FT = 1
# Attempt to pack with harfbuzz (allowing sharing between extensions)
# use fontTools to attempt overflow resolution.
HB_FT = 2
# Fallback if HB/FT packing gets stuck. Pack only with fontTools, don't allow sharing between
# extensions.
FT_FALLBACK = 3
class BaseTTXConverter(DefaultTable):
"""Generic base class for TTX table converters. It functions as an
adapter between the TTX (ttLib actually) table model and the model
we use for OpenType tables, which is necessarily subtly different.
"""
def decompile(self, data, font):
"""Create an object from the binary data. Called automatically on access."""
from . import otTables
reader = OTTableReader(data, tableTag=self.tableTag)
tableClass = getattr(otTables, self.tableTag)
self.table = tableClass()
self.table.decompile(reader, font)
def compile(self, font):
"""Compiles the table into binary. Called automatically on save."""
# General outline:
# Create a top-level OTTableWriter for the GPOS/GSUB table.
# Call the compile method for the the table
# for each 'converter' record in the table converter list
# call converter's write method for each item in the value.
# - For simple items, the write method adds a string to the
# writer's self.items list.
# - For Struct/Table/Subtable items, it add first adds new writer to the
# to the writer's self.items, then calls the item's compile method.
# This creates a tree of writers, rooted at the GUSB/GPOS writer, with
# each writer representing a table, and the writer.items list containing
# the child data strings and writers.
# call the getAllData method
# call _doneWriting, which removes duplicates
# call _gatherTables. This traverses the tables, adding unique occurences to a flat list of tables
# Traverse the flat list of tables, calling getDataLength on each to update their position
# Traverse the flat list of tables again, calling getData each get the data in the table, now that
# pos's and offset are known.
# If a lookup subtable overflows an offset, we have to start all over.
overflowRecord = None
# this is 3-state option: default (None) means automatically use hb.repack or
# silently fall back if it fails; True, use it and raise error if not possible
# or it errors out; False, don't use it, even if you can.
use_hb_repack = font.cfg[USE_HARFBUZZ_REPACKER]
if self.tableTag in ("GSUB", "GPOS"):
if use_hb_repack is False:
log.debug(
"hb.repack disabled, compiling '%s' with pure-python serializer",
self.tableTag,
)
elif not have_uharfbuzz:
if use_hb_repack is True:
raise ImportError("No module named 'uharfbuzz'")
else:
assert use_hb_repack is None
log.debug(
"uharfbuzz not found, compiling '%s' with pure-python serializer",
self.tableTag,
)
if (
use_hb_repack in (None, True)
and have_uharfbuzz
and self.tableTag in ("GSUB", "GPOS")
):
state = RepackerState.HB_FT
else:
state = RepackerState.PURE_FT
hb_first_error_logged = False
lastOverflowRecord = None
while True:
try:
writer = OTTableWriter(tableTag=self.tableTag)
self.table.compile(writer, font)
if state == RepackerState.HB_FT:
return self.tryPackingHarfbuzz(writer, hb_first_error_logged)
elif state == RepackerState.PURE_FT:
return self.tryPackingFontTools(writer)
elif state == RepackerState.FT_FALLBACK:
# Run packing with FontTools only, but don't return the result as it will
# not be optimally packed. Once a successful packing has been found, state is
# changed back to harfbuzz packing to produce the final, optimal, packing.
self.tryPackingFontTools(writer)
log.debug(
"Re-enabling sharing between extensions and switching back to "
"harfbuzz+fontTools packing."
)
state = RepackerState.HB_FT
except OTLOffsetOverflowError as e:
hb_first_error_logged = True
ok = self.tryResolveOverflow(font, e, lastOverflowRecord)
lastOverflowRecord = e.value
if ok:
continue
if state is RepackerState.HB_FT:
log.debug(
"Harfbuzz packing out of resolutions, disabling sharing between extensions and "
"switching to fontTools only packing."
)
state = RepackerState.FT_FALLBACK
else:
raise
def tryPackingHarfbuzz(self, writer, hb_first_error_logged):
try:
log.debug("serializing '%s' with hb.repack", self.tableTag)
return writer.getAllDataUsingHarfbuzz(self.tableTag)
except (ValueError, MemoryError, hb.RepackerError) as e:
# Only log hb repacker errors the first time they occur in
# the offset-overflow resolution loop, they are just noisy.
# Maybe we can revisit this if/when uharfbuzz actually gives
# us more info as to why hb.repack failed...
if not hb_first_error_logged:
error_msg = f"{type(e).__name__}"
if str(e) != "":
error_msg += f": {e}"
log.warning(
"hb.repack failed to serialize '%s', attempting fonttools resolutions "
"; the error message was: %s",
self.tableTag,
error_msg,
)
hb_first_error_logged = True
return writer.getAllData(remove_duplicate=False)
def tryPackingFontTools(self, writer):
return writer.getAllData()
def tryResolveOverflow(self, font, e, lastOverflowRecord):
ok = 0
if lastOverflowRecord == e.value:
# Oh well...
return ok
overflowRecord = e.value
log.info("Attempting to fix OTLOffsetOverflowError %s", e)
if overflowRecord.itemName is None:
from .otTables import fixLookupOverFlows
ok = fixLookupOverFlows(font, overflowRecord)
else:
from .otTables import fixSubTableOverFlows
ok = fixSubTableOverFlows(font, overflowRecord)
if ok:
return ok
# Try upgrading lookup to Extension and hope
# that cross-lookup sharing not happening would
# fix overflow...
from .otTables import fixLookupOverFlows
return fixLookupOverFlows(font, overflowRecord)
def toXML(self, writer, font):
self.table.toXML2(writer, font)
def fromXML(self, name, attrs, content, font):
from . import otTables
if not hasattr(self, "table"):
tableClass = getattr(otTables, self.tableTag)
self.table = tableClass()
self.table.fromXML(name, attrs, content, font)
self.table.populateDefaults()
def ensureDecompiled(self, recurse=True):
self.table.ensureDecompiled(recurse=recurse)
# https://github.com/fonttools/fonttools/pull/2285#issuecomment-834652928
assert len(struct.pack("i", 0)) == 4
assert array.array("i").itemsize == 4, "Oops, file a bug against fonttools."
class OTTableReader(object):
"""Helper class to retrieve data from an OpenType table."""
__slots__ = ("data", "offset", "pos", "localState", "tableTag")
def __init__(self, data, localState=None, offset=0, tableTag=None):
self.data = data
self.offset = offset
self.pos = offset
self.localState = localState
self.tableTag = tableTag
def advance(self, count):
self.pos += count
def seek(self, pos):
self.pos = pos
def copy(self):
other = self.__class__(self.data, self.localState, self.offset, self.tableTag)
other.pos = self.pos
return other
def getSubReader(self, offset):
offset = self.offset + offset
return self.__class__(self.data, self.localState, offset, self.tableTag)
def readValue(self, typecode, staticSize):
pos = self.pos
newpos = pos + staticSize
(value,) = struct.unpack(f">{typecode}", self.data[pos:newpos])
self.pos = newpos
return value
def readArray(self, typecode, staticSize, count):
pos = self.pos
newpos = pos + count * staticSize
value = array.array(typecode, self.data[pos:newpos])
if sys.byteorder != "big":
value.byteswap()
self.pos = newpos
return value.tolist()
def readInt8(self):
return self.readValue("b", staticSize=1)
def readInt8Array(self, count):
return self.readArray("b", staticSize=1, count=count)
def readShort(self):
return self.readValue("h", staticSize=2)
def readShortArray(self, count):
return self.readArray("h", staticSize=2, count=count)
def readLong(self):
return self.readValue("i", staticSize=4)
def readLongArray(self, count):
return self.readArray("i", staticSize=4, count=count)
def readUInt8(self):
return self.readValue("B", staticSize=1)
def readUInt8Array(self, count):
return self.readArray("B", staticSize=1, count=count)
def readUShort(self):
return self.readValue("H", staticSize=2)
def readUShortArray(self, count):
return self.readArray("H", staticSize=2, count=count)
def readULong(self):
return self.readValue("I", staticSize=4)
def readULongArray(self, count):
return self.readArray("I", staticSize=4, count=count)
def readUInt24(self):
pos = self.pos
newpos = pos + 3
(value,) = struct.unpack(">l", b"\0" + self.data[pos:newpos])
self.pos = newpos
return value
def readUInt24Array(self, count):
return [self.readUInt24() for _ in range(count)]
def readTag(self):
pos = self.pos
newpos = pos + 4
value = Tag(self.data[pos:newpos])
assert len(value) == 4, value
self.pos = newpos
return value
def readData(self, count):
pos = self.pos
newpos = pos + count
value = self.data[pos:newpos]
self.pos = newpos
return value
def __setitem__(self, name, value):
state = self.localState.copy() if self.localState else dict()
state[name] = value
self.localState = state
def __getitem__(self, name):
return self.localState and self.localState[name]
def __contains__(self, name):
return self.localState and name in self.localState
class OffsetToWriter(object):
def __init__(self, subWriter, offsetSize):
self.subWriter = subWriter
self.offsetSize = offsetSize
def __eq__(self, other):
if type(self) != type(other):
return NotImplemented
return self.subWriter == other.subWriter and self.offsetSize == other.offsetSize
def __hash__(self):
# only works after self._doneWriting() has been called
return hash((self.subWriter, self.offsetSize))
class OTTableWriter(object):
"""Helper class to gather and assemble data for OpenType tables."""
def __init__(self, localState=None, tableTag=None):
self.items = []
self.pos = None
self.localState = localState
self.tableTag = tableTag
self.parent = None
def __setitem__(self, name, value):
state = self.localState.copy() if self.localState else dict()
state[name] = value
self.localState = state
def __getitem__(self, name):
return self.localState[name]
def __delitem__(self, name):
del self.localState[name]
# assembler interface
def getDataLength(self):
"""Return the length of this table in bytes, without subtables."""
l = 0
for item in self.items:
if hasattr(item, "getCountData"):
l += item.size
elif hasattr(item, "subWriter"):
l += item.offsetSize
else:
l = l + len(item)
return l
def getData(self):
"""Assemble the data for this writer/table, without subtables."""
items = list(self.items) # make a shallow copy
pos = self.pos
numItems = len(items)
for i in range(numItems):
item = items[i]
if hasattr(item, "subWriter"):
if item.offsetSize == 4:
items[i] = packULong(item.subWriter.pos - pos)
elif item.offsetSize == 2:
try:
items[i] = packUShort(item.subWriter.pos - pos)
except struct.error:
# provide data to fix overflow problem.
overflowErrorRecord = self.getOverflowErrorRecord(
item.subWriter
)
raise OTLOffsetOverflowError(overflowErrorRecord)
elif item.offsetSize == 3:
items[i] = packUInt24(item.subWriter.pos - pos)
else:
raise ValueError(item.offsetSize)
return bytesjoin(items)
def getDataForHarfbuzz(self):
"""Assemble the data for this writer/table with all offset field set to 0"""
items = list(self.items)
packFuncs = {2: packUShort, 3: packUInt24, 4: packULong}
for i, item in enumerate(items):
if hasattr(item, "subWriter"):
# Offset value is not needed in harfbuzz repacker, so setting offset to 0 to avoid overflow here
if item.offsetSize in packFuncs:
items[i] = packFuncs[item.offsetSize](0)
else:
raise ValueError(item.offsetSize)
return bytesjoin(items)
def __hash__(self):
# only works after self._doneWriting() has been called
return hash(self.items)
def __ne__(self, other):
result = self.__eq__(other)
return result if result is NotImplemented else not result
def __eq__(self, other):
if type(self) != type(other):
return NotImplemented
return self.items == other.items
def _doneWriting(self, internedTables, shareExtension=False):
# Convert CountData references to data string items
# collapse duplicate table references to a unique entry
# "tables" are OTTableWriter objects.
# For Extension Lookup types, we can
# eliminate duplicates only within the tree under the Extension Lookup,
# as offsets may exceed 64K even between Extension LookupTable subtables.
isExtension = hasattr(self, "Extension")
# Certain versions of Uniscribe reject the font if the GSUB/GPOS top-level
# arrays (ScriptList, FeatureList, LookupList) point to the same, possibly
# empty, array. So, we don't share those.
# See: https://github.com/fonttools/fonttools/issues/518
dontShare = hasattr(self, "DontShare")
if isExtension and not shareExtension:
internedTables = {}
items = self.items
for i in range(len(items)):
item = items[i]
if hasattr(item, "getCountData"):
items[i] = item.getCountData()
elif hasattr(item, "subWriter"):
item.subWriter._doneWriting(
internedTables, shareExtension=shareExtension
)
# At this point, all subwriters are hashable based on their items.
# (See hash and comparison magic methods above.) So the ``setdefault``
# call here will return the first writer object we've seen with
# equal content, or store it in the dictionary if it's not been
# seen yet. We therefore replace the subwriter object with an equivalent
# object, which deduplicates the tree.
if not dontShare:
items[i].subWriter = internedTables.setdefault(
item.subWriter, item.subWriter
)
self.items = tuple(items)
def _gatherTables(self, tables, extTables, done):
# Convert table references in self.items tree to a flat
# list of tables in depth-first traversal order.
# "tables" are OTTableWriter objects.
# We do the traversal in reverse order at each level, in order to
# resolve duplicate references to be the last reference in the list of tables.
# For extension lookups, duplicate references can be merged only within the
# writer tree under the extension lookup.
done[id(self)] = True
numItems = len(self.items)
iRange = list(range(numItems))
iRange.reverse()
isExtension = hasattr(self, "Extension")
selfTables = tables
if isExtension:
assert (
extTables is not None
), "Program or XML editing error. Extension subtables cannot contain extensions subtables"
tables, extTables, done = extTables, None, {}
# add Coverage table if it is sorted last.
sortCoverageLast = False
if hasattr(self, "sortCoverageLast"):
# Find coverage table
for i in range(numItems):
item = self.items[i]
if (
hasattr(item, "subWriter")
and getattr(item.subWriter, "name", None) == "Coverage"
):
sortCoverageLast = True
break
if id(item.subWriter) not in done:
item.subWriter._gatherTables(tables, extTables, done)
else:
# We're a new parent of item
pass
for i in iRange:
item = self.items[i]
if not hasattr(item, "subWriter"):
continue
if (
sortCoverageLast
and (i == 1)
and getattr(item.subWriter, "name", None) == "Coverage"
):
# we've already 'gathered' it above
continue
if id(item.subWriter) not in done:
item.subWriter._gatherTables(tables, extTables, done)
else:
# Item is already written out by other parent
pass
selfTables.append(self)
def _gatherGraphForHarfbuzz(self, tables, obj_list, done, objidx, virtual_edges):
real_links = []
virtual_links = []
item_idx = objidx
# Merge virtual_links from parent
for idx in virtual_edges:
virtual_links.append((0, 0, idx))
sortCoverageLast = False
coverage_idx = 0
if hasattr(self, "sortCoverageLast"):
# Find coverage table
for i, item in enumerate(self.items):
if getattr(item, "name", None) == "Coverage":
sortCoverageLast = True
if id(item) not in done:
coverage_idx = item_idx = item._gatherGraphForHarfbuzz(
tables, obj_list, done, item_idx, virtual_edges
)
else:
coverage_idx = done[id(item)]
virtual_edges.append(coverage_idx)
break
child_idx = 0
offset_pos = 0
for i, item in enumerate(self.items):
if hasattr(item, "subWriter"):
pos = offset_pos
elif hasattr(item, "getCountData"):
offset_pos += item.size
continue
else:
offset_pos = offset_pos + len(item)
continue
if id(item.subWriter) not in done:
child_idx = item_idx = item.subWriter._gatherGraphForHarfbuzz(
tables, obj_list, done, item_idx, virtual_edges
)
else:
child_idx = done[id(item.subWriter)]
real_edge = (pos, item.offsetSize, child_idx)
real_links.append(real_edge)
offset_pos += item.offsetSize
tables.append(self)
obj_list.append((real_links, virtual_links))
item_idx += 1
done[id(self)] = item_idx
if sortCoverageLast:
virtual_edges.pop()
return item_idx
def getAllDataUsingHarfbuzz(self, tableTag):
"""The Whole table is represented as a Graph.
Assemble graph data and call Harfbuzz repacker to pack the table.
Harfbuzz repacker is faster and retain as much sub-table sharing as possible, see also:
https://github.com/harfbuzz/harfbuzz/blob/main/docs/repacker.md
The input format for hb.repack() method is explained here:
https://github.com/harfbuzz/uharfbuzz/blob/main/src/uharfbuzz/_harfbuzz.pyx#L1149
"""
internedTables = {}
self._doneWriting(internedTables, shareExtension=True)
tables = []
obj_list = []
done = {}
objidx = 0
virtual_edges = []
self._gatherGraphForHarfbuzz(tables, obj_list, done, objidx, virtual_edges)
# Gather all data in two passes: the absolute positions of all
# subtable are needed before the actual data can be assembled.
pos = 0
for table in tables:
table.pos = pos
pos = pos + table.getDataLength()
data = []
for table in tables:
tableData = table.getDataForHarfbuzz()
data.append(tableData)
if hasattr(hb, "repack_with_tag"):
return hb.repack_with_tag(str(tableTag), data, obj_list)
else:
return hb.repack(data, obj_list)
def getAllData(self, remove_duplicate=True):
"""Assemble all data, including all subtables."""
if remove_duplicate:
internedTables = {}
self._doneWriting(internedTables)
tables = []
extTables = []
done = {}
self._gatherTables(tables, extTables, done)
tables.reverse()
extTables.reverse()
# Gather all data in two passes: the absolute positions of all
# subtable are needed before the actual data can be assembled.
pos = 0
for table in tables:
table.pos = pos
pos = pos + table.getDataLength()
for table in extTables:
table.pos = pos
pos = pos + table.getDataLength()
data = []
for table in tables:
tableData = table.getData()
data.append(tableData)
for table in extTables:
tableData = table.getData()
data.append(tableData)
return bytesjoin(data)
# interface for gathering data, as used by table.compile()
def getSubWriter(self):
subwriter = self.__class__(self.localState, self.tableTag)
subwriter.parent = (
self # because some subtables have idential values, we discard
)
# the duplicates under the getAllData method. Hence some
# subtable writers can have more than one parent writer.
# But we just care about first one right now.
return subwriter
def writeValue(self, typecode, value):
self.items.append(struct.pack(f">{typecode}", value))
def writeArray(self, typecode, values):
a = array.array(typecode, values)
if sys.byteorder != "big":
a.byteswap()
self.items.append(a.tobytes())
def writeInt8(self, value):
assert -128 <= value < 128, value
self.items.append(struct.pack(">b", value))
def writeInt8Array(self, values):
self.writeArray("b", values)
def writeShort(self, value):
assert -32768 <= value < 32768, value
self.items.append(struct.pack(">h", value))
def writeShortArray(self, values):
self.writeArray("h", values)
def writeLong(self, value):
self.items.append(struct.pack(">i", value))
def writeLongArray(self, values):
self.writeArray("i", values)
def writeUInt8(self, value):
assert 0 <= value < 256, value
self.items.append(struct.pack(">B", value))
def writeUInt8Array(self, values):
self.writeArray("B", values)
def writeUShort(self, value):
assert 0 <= value < 0x10000, value
self.items.append(struct.pack(">H", value))
def writeUShortArray(self, values):
self.writeArray("H", values)
def writeULong(self, value):
self.items.append(struct.pack(">I", value))
def writeULongArray(self, values):
self.writeArray("I", values)
def writeUInt24(self, value):
assert 0 <= value < 0x1000000, value
b = struct.pack(">L", value)
self.items.append(b[1:])
def writeUInt24Array(self, values):
for value in values:
self.writeUInt24(value)
def writeTag(self, tag):
tag = Tag(tag).tobytes()
assert len(tag) == 4, tag
self.items.append(tag)
def writeSubTable(self, subWriter, offsetSize):
self.items.append(OffsetToWriter(subWriter, offsetSize))
def writeCountReference(self, table, name, size=2, value=None):
ref = CountReference(table, name, size=size, value=value)
self.items.append(ref)
return ref
def writeStruct(self, format, values):
data = struct.pack(*(format,) + values)
self.items.append(data)
def writeData(self, data):
self.items.append(data)
def getOverflowErrorRecord(self, item):
LookupListIndex = SubTableIndex = itemName = itemIndex = None
if self.name == "LookupList":
LookupListIndex = item.repeatIndex
elif self.name == "Lookup":
LookupListIndex = self.repeatIndex
SubTableIndex = item.repeatIndex
else:
itemName = getattr(item, "name", "<none>")
if hasattr(item, "repeatIndex"):
itemIndex = item.repeatIndex
if self.name == "SubTable":
LookupListIndex = self.parent.repeatIndex
SubTableIndex = self.repeatIndex
elif self.name == "ExtSubTable":
LookupListIndex = self.parent.parent.repeatIndex
SubTableIndex = self.parent.repeatIndex
else: # who knows how far below the SubTable level we are! Climb back up to the nearest subtable.
itemName = ".".join([self.name, itemName])
p1 = self.parent
while p1 and p1.name not in ["ExtSubTable", "SubTable"]:
itemName = ".".join([p1.name, itemName])
p1 = p1.parent
if p1:
if p1.name == "ExtSubTable":
LookupListIndex = p1.parent.parent.repeatIndex
SubTableIndex = p1.parent.repeatIndex
else:
LookupListIndex = p1.parent.repeatIndex
SubTableIndex = p1.repeatIndex
return OverflowErrorRecord(
(self.tableTag, LookupListIndex, SubTableIndex, itemName, itemIndex)
)
class CountReference(object):
"""A reference to a Count value, not a count of references."""
def __init__(self, table, name, size=None, value=None):
self.table = table
self.name = name
self.size = size
if value is not None:
self.setValue(value)
def setValue(self, value):
table = self.table
name = self.name
if table[name] is None:
table[name] = value
else:
assert table[name] == value, (name, table[name], value)
def getValue(self):
return self.table[self.name]
def getCountData(self):
v = self.table[self.name]
if v is None:
v = 0
return {1: packUInt8, 2: packUShort, 4: packULong}[self.size](v)
def packUInt8(value):
return struct.pack(">B", value)
def packUShort(value):
return struct.pack(">H", value)
def packULong(value):
assert 0 <= value < 0x100000000, value
return struct.pack(">I", value)
def packUInt24(value):
assert 0 <= value < 0x1000000, value
return struct.pack(">I", value)[1:]
class BaseTable(object):
"""Generic base class for all OpenType (sub)tables."""
def __getattr__(self, attr):
reader = self.__dict__.get("reader")
if reader:
del self.reader
font = self.font
del self.font
self.decompile(reader, font)
return getattr(self, attr)
raise AttributeError(attr)
def ensureDecompiled(self, recurse=False):
reader = self.__dict__.get("reader")
if reader:
del self.reader
font = self.font
del self.font
self.decompile(reader, font)
if recurse:
for subtable in self.iterSubTables():
subtable.value.ensureDecompiled(recurse)
def __getstate__(self):
# before copying/pickling 'lazy' objects, make a shallow copy of OTTableReader
# https://github.com/fonttools/fonttools/issues/2965
if "reader" in self.__dict__:
state = self.__dict__.copy()
state["reader"] = self.__dict__["reader"].copy()
return state
return self.__dict__
@classmethod
def getRecordSize(cls, reader):
totalSize = 0
for conv in cls.converters:
size = conv.getRecordSize(reader)
if size is NotImplemented:
return NotImplemented
countValue = 1
if conv.repeat:
if conv.repeat in reader:
countValue = reader[conv.repeat] + conv.aux
else:
return NotImplemented
totalSize += size * countValue
return totalSize
def getConverters(self):
return self.converters
def getConverterByName(self, name):
return self.convertersByName[name]
def populateDefaults(self, propagator=None):
for conv in self.getConverters():
if conv.repeat:
if not hasattr(self, conv.name):
setattr(self, conv.name, [])
countValue = len(getattr(self, conv.name)) - conv.aux
try:
count_conv = self.getConverterByName(conv.repeat)
setattr(self, conv.repeat, countValue)
except KeyError:
# conv.repeat is a propagated count
if propagator and conv.repeat in propagator:
propagator[conv.repeat].setValue(countValue)
else:
if conv.aux and not eval(conv.aux, None, self.__dict__):
continue
if hasattr(self, conv.name):
continue # Warn if it should NOT be present?!
if hasattr(conv, "writeNullOffset"):
setattr(self, conv.name, None) # Warn?
# elif not conv.isCount:
# # Warn?
# pass
if hasattr(conv, "DEFAULT"):
# OptionalValue converters (e.g. VarIndex)
setattr(self, conv.name, conv.DEFAULT)
def decompile(self, reader, font):
self.readFormat(reader)
table = {}
self.__rawTable = table # for debugging
for conv in self.getConverters():
if conv.name == "SubTable":
conv = conv.getConverter(reader.tableTag, table["LookupType"])
if conv.name == "ExtSubTable":
conv = conv.getConverter(reader.tableTag, table["ExtensionLookupType"])
if conv.name == "FeatureParams":
conv = conv.getConverter(reader["FeatureTag"])
if conv.name == "SubStruct":
conv = conv.getConverter(reader.tableTag, table["MorphType"])
try:
if conv.repeat:
if isinstance(conv.repeat, int):
countValue = conv.repeat
elif conv.repeat in table:
countValue = table[conv.repeat]
else:
# conv.repeat is a propagated count
countValue = reader[conv.repeat]
countValue += conv.aux
table[conv.name] = conv.readArray(reader, font, table, countValue)
else:
if conv.aux and not eval(conv.aux, None, table):
continue
table[conv.name] = conv.read(reader, font, table)
if conv.isPropagated:
reader[conv.name] = table[conv.name]
except Exception as e:
name = conv.name
e.args = e.args + (name,)
raise
if hasattr(self, "postRead"):
self.postRead(table, font)
else:
self.__dict__.update(table)
del self.__rawTable # succeeded, get rid of debugging info
def compile(self, writer, font):
self.ensureDecompiled()
# TODO Following hack to be removed by rewriting how FormatSwitching tables
# are handled.
# https://github.com/fonttools/fonttools/pull/2238#issuecomment-805192631
if hasattr(self, "preWrite"):
deleteFormat = not hasattr(self, "Format")
table = self.preWrite(font)
deleteFormat = deleteFormat and hasattr(self, "Format")
else:
deleteFormat = False
table = self.__dict__.copy()
# some count references may have been initialized in a custom preWrite; we set
# these in the writer's state beforehand (instead of sequentially) so they will
# be propagated to all nested subtables even if the count appears in the current
# table only *after* the offset to the subtable that it is counting.
for conv in self.getConverters():
if conv.isCount and conv.isPropagated:
value = table.get(conv.name)
if isinstance(value, CountReference):
writer[conv.name] = value
if hasattr(self, "sortCoverageLast"):
writer.sortCoverageLast = 1
if hasattr(self, "DontShare"):
writer.DontShare = True
if hasattr(self.__class__, "LookupType"):
writer["LookupType"].setValue(self.__class__.LookupType)
self.writeFormat(writer)
for conv in self.getConverters():
value = table.get(
conv.name
) # TODO Handle defaults instead of defaulting to None!
if conv.repeat:
if value is None:
value = []
countValue = len(value) - conv.aux
if isinstance(conv.repeat, int):
assert len(value) == conv.repeat, "expected %d values, got %d" % (
conv.repeat,
len(value),
)
elif conv.repeat in table:
CountReference(table, conv.repeat, value=countValue)
else:
# conv.repeat is a propagated count
writer[conv.repeat].setValue(countValue)
try:
conv.writeArray(writer, font, table, value)
except Exception as e:
e.args = e.args + (conv.name + "[]",)
raise
elif conv.isCount:
# Special-case Count values.
# Assumption: a Count field will *always* precede
# the actual array(s).
# We need a default value, as it may be set later by a nested
# table. We will later store it here.
# We add a reference: by the time the data is assembled
# the Count value will be filled in.
# We ignore the current count value since it will be recomputed,
# unless it's a CountReference that was already initialized in a custom preWrite.
if isinstance(value, CountReference):
ref = value
ref.size = conv.staticSize
writer.writeData(ref)
table[conv.name] = ref.getValue()
else:
ref = writer.writeCountReference(table, conv.name, conv.staticSize)
table[conv.name] = None
if conv.isPropagated:
writer[conv.name] = ref
elif conv.isLookupType:
# We make sure that subtables have the same lookup type,
# and that the type is the same as the one set on the
# Lookup object, if any is set.
if conv.name not in table:
table[conv.name] = None
ref = writer.writeCountReference(
table, conv.name, conv.staticSize, table[conv.name]
)
writer["LookupType"] = ref
else:
if conv.aux and not eval(conv.aux, None, table):
continue
try:
conv.write(writer, font, table, value)
except Exception as e:
name = value.__class__.__name__ if value is not None else conv.name
e.args = e.args + (name,)
raise
if conv.isPropagated:
writer[conv.name] = value
if deleteFormat:
del self.Format
def readFormat(self, reader):
pass
def writeFormat(self, writer):
pass
def toXML(self, xmlWriter, font, attrs=None, name=None):
tableName = name if name else self.__class__.__name__
if attrs is None:
attrs = []
if hasattr(self, "Format"):
attrs = attrs + [("Format", self.Format)]
xmlWriter.begintag(tableName, attrs)
xmlWriter.newline()
self.toXML2(xmlWriter, font)
xmlWriter.endtag(tableName)
xmlWriter.newline()
def toXML2(self, xmlWriter, font):
# Simpler variant of toXML, *only* for the top level tables (like GPOS, GSUB).
# This is because in TTX our parent writes our main tag, and in otBase.py we
# do it ourselves. I think I'm getting schizophrenic...
for conv in self.getConverters():
if conv.repeat:
value = getattr(self, conv.name, [])
for i in range(len(value)):
item = value[i]
conv.xmlWrite(xmlWriter, font, item, conv.name, [("index", i)])
else:
if conv.aux and not eval(conv.aux, None, vars(self)):
continue
value = getattr(
self, conv.name, None
) # TODO Handle defaults instead of defaulting to None!
conv.xmlWrite(xmlWriter, font, value, conv.name, [])
def fromXML(self, name, attrs, content, font):
try:
conv = self.getConverterByName(name)
except KeyError:
raise # XXX on KeyError, raise nice error
value = conv.xmlRead(attrs, content, font)
# Some manually-written tables have a conv.repeat of ""
# to represent lists. Hence comparing to None here to
# allow those lists to be read correctly from XML.
if conv.repeat is not None:
seq = getattr(self, conv.name, None)
if seq is None:
seq = []
setattr(self, conv.name, seq)
seq.append(value)
else:
setattr(self, conv.name, value)
def __ne__(self, other):
result = self.__eq__(other)
return result if result is NotImplemented else not result
def __eq__(self, other):
if type(self) != type(other):
return NotImplemented
self.ensureDecompiled()
other.ensureDecompiled()
return self.__dict__ == other.__dict__
class SubTableEntry(NamedTuple):
"""See BaseTable.iterSubTables()"""
name: str
value: "BaseTable"
index: Optional[int] = None # index into given array, None for single values
def iterSubTables(self) -> Iterator[SubTableEntry]:
"""Yield (name, value, index) namedtuples for all subtables of current table.
A sub-table is an instance of BaseTable (or subclass thereof) that is a child
of self, the current parent table.
The tuples also contain the attribute name (str) of the of parent table to get
a subtable, and optionally, for lists of subtables (i.e. attributes associated
with a converter that has a 'repeat'), an index into the list containing the
given subtable value.
This method can be useful to traverse trees of otTables.
"""
for conv in self.getConverters():
name = conv.name
value = getattr(self, name, None)
if value is None:
continue
if isinstance(value, BaseTable):
yield self.SubTableEntry(name, value)
elif isinstance(value, list):
yield from (
self.SubTableEntry(name, v, index=i)
for i, v in enumerate(value)
if isinstance(v, BaseTable)
)
# instance (not @class)method for consistency with FormatSwitchingBaseTable
def getVariableAttrs(self):
return getVariableAttrs(self.__class__)
class FormatSwitchingBaseTable(BaseTable):
"""Minor specialization of BaseTable, for tables that have multiple
formats, eg. CoverageFormat1 vs. CoverageFormat2."""
@classmethod
def getRecordSize(cls, reader):
return NotImplemented
def getConverters(self):
try:
fmt = self.Format
except AttributeError:
# some FormatSwitchingBaseTables (e.g. Coverage) no longer have 'Format'
# attribute after fully decompiled, only gain one in preWrite before being
# recompiled. In the decompiled state, these hand-coded classes defined in
# otTables.py lose their format-specific nature and gain more high-level
# attributes that are not tied to converters.
return []
return self.converters.get(self.Format, [])
def getConverterByName(self, name):
return self.convertersByName[self.Format][name]
def readFormat(self, reader):
self.Format = reader.readUShort()
def writeFormat(self, writer):
writer.writeUShort(self.Format)
def toXML(self, xmlWriter, font, attrs=None, name=None):
BaseTable.toXML(self, xmlWriter, font, attrs, name)
def getVariableAttrs(self):
return getVariableAttrs(self.__class__, self.Format)
class UInt8FormatSwitchingBaseTable(FormatSwitchingBaseTable):
def readFormat(self, reader):
self.Format = reader.readUInt8()
def writeFormat(self, writer):
writer.writeUInt8(self.Format)
formatSwitchingBaseTables = {
"uint16": FormatSwitchingBaseTable,
"uint8": UInt8FormatSwitchingBaseTable,
}
def getFormatSwitchingBaseTableClass(formatType):
try:
return formatSwitchingBaseTables[formatType]
except KeyError:
raise TypeError(f"Unsupported format type: {formatType!r}")
# memoize since these are parsed from otData.py, thus stay constant
@lru_cache()
def getVariableAttrs(cls: BaseTable, fmt: Optional[int] = None) -> Tuple[str]:
"""Return sequence of variable table field names (can be empty).
Attributes are deemed "variable" when their otData.py's description contain
'VarIndexBase + {offset}', e.g. COLRv1 PaintVar* tables.
"""
if not issubclass(cls, BaseTable):
raise TypeError(cls)
if issubclass(cls, FormatSwitchingBaseTable):
if fmt is None:
raise TypeError(f"'fmt' is required for format-switching {cls.__name__}")
converters = cls.convertersByName[fmt]
else:
converters = cls.convertersByName
# assume if no 'VarIndexBase' field is present, table has no variable fields
if "VarIndexBase" not in converters:
return ()
varAttrs = {}
for name, conv in converters.items():
offset = conv.getVarIndexOffset()
if offset is not None:
varAttrs[name] = offset
return tuple(sorted(varAttrs, key=varAttrs.__getitem__))
#
# Support for ValueRecords
#
# This data type is so different from all other OpenType data types that
# it requires quite a bit of code for itself. It even has special support
# in OTTableReader and OTTableWriter...
#
valueRecordFormat = [
# Mask Name isDevice signed
(0x0001, "XPlacement", 0, 1),
(0x0002, "YPlacement", 0, 1),
(0x0004, "XAdvance", 0, 1),
(0x0008, "YAdvance", 0, 1),
(0x0010, "XPlaDevice", 1, 0),
(0x0020, "YPlaDevice", 1, 0),
(0x0040, "XAdvDevice", 1, 0),
(0x0080, "YAdvDevice", 1, 0),
# reserved:
(0x0100, "Reserved1", 0, 0),
(0x0200, "Reserved2", 0, 0),
(0x0400, "Reserved3", 0, 0),
(0x0800, "Reserved4", 0, 0),
(0x1000, "Reserved5", 0, 0),
(0x2000, "Reserved6", 0, 0),
(0x4000, "Reserved7", 0, 0),
(0x8000, "Reserved8", 0, 0),
]
def _buildDict():
d = {}
for mask, name, isDevice, signed in valueRecordFormat:
d[name] = mask, isDevice, signed
return d
valueRecordFormatDict = _buildDict()
class ValueRecordFactory(object):
"""Given a format code, this object convert ValueRecords."""
def __init__(self, valueFormat):
format = []
for mask, name, isDevice, signed in valueRecordFormat:
if valueFormat & mask:
format.append((name, isDevice, signed))
self.format = format
def __len__(self):
return len(self.format)
def readValueRecord(self, reader, font):
format = self.format
if not format:
return None
valueRecord = ValueRecord()
for name, isDevice, signed in format:
if signed:
value = reader.readShort()
else:
value = reader.readUShort()
if isDevice:
if value:
from . import otTables
subReader = reader.getSubReader(value)
value = getattr(otTables, name)()
value.decompile(subReader, font)
else:
value = None
setattr(valueRecord, name, value)
return valueRecord
def writeValueRecord(self, writer, font, valueRecord):
for name, isDevice, signed in self.format:
value = getattr(valueRecord, name, 0)
if isDevice:
if value:
subWriter = writer.getSubWriter()
writer.writeSubTable(subWriter, offsetSize=2)
value.compile(subWriter, font)
else:
writer.writeUShort(0)
elif signed:
writer.writeShort(value)
else:
writer.writeUShort(value)
class ValueRecord(object):
# see ValueRecordFactory
def __init__(self, valueFormat=None, src=None):
if valueFormat is not None:
for mask, name, isDevice, signed in valueRecordFormat:
if valueFormat & mask:
setattr(self, name, None if isDevice else 0)
if src is not None:
for key, val in src.__dict__.items():
if not hasattr(self, key):
continue
setattr(self, key, val)
elif src is not None:
self.__dict__ = src.__dict__.copy()
def getFormat(self):
format = 0
for name in self.__dict__.keys():
format = format | valueRecordFormatDict[name][0]
return format
def getEffectiveFormat(self):
format = 0
for name, value in self.__dict__.items():
if value:
format = format | valueRecordFormatDict[name][0]
return format
def toXML(self, xmlWriter, font, valueName, attrs=None):
if attrs is None:
simpleItems = []
else:
simpleItems = list(attrs)
for mask, name, isDevice, format in valueRecordFormat[:4]: # "simple" values
if hasattr(self, name):
simpleItems.append((name, getattr(self, name)))
deviceItems = []
for mask, name, isDevice, format in valueRecordFormat[4:8]: # device records
if hasattr(self, name):
device = getattr(self, name)
if device is not None:
deviceItems.append((name, device))
if deviceItems:
xmlWriter.begintag(valueName, simpleItems)
xmlWriter.newline()
for name, deviceRecord in deviceItems:
if deviceRecord is not None:
deviceRecord.toXML(xmlWriter, font, name=name)
xmlWriter.endtag(valueName)
xmlWriter.newline()
else:
xmlWriter.simpletag(valueName, simpleItems)
xmlWriter.newline()
def fromXML(self, name, attrs, content, font):
from . import otTables
for k, v in attrs.items():
setattr(self, k, int(v))
for element in content:
if not isinstance(element, tuple):
continue
name, attrs, content = element
value = getattr(otTables, name)()
for elem2 in content:
if not isinstance(elem2, tuple):
continue
name2, attrs2, content2 = elem2
value.fromXML(name2, attrs2, content2, font)
setattr(self, name, value)
def __ne__(self, other):
result = self.__eq__(other)
return result if result is NotImplemented else not result
def __eq__(self, other):
if type(self) != type(other):
return NotImplemented
return self.__dict__ == other.__dict__
Reference in New Issue Copy Permalink