Python sstruct.pack函数代码示例

	def compile(self, ttFont):
		dataList = []
		dataList.append(sstruct.pack(bigGlyphMetricsFormat, self.metrics))
		dataList.append(struct.pack(">H", len(self.componentArray)))
		for curComponent in self.componentArray:
			curComponent.glyphCode = ttFont.getGlyphID(curComponent.name)
			dataList.append(sstruct.pack(ebdtComponentFormat, curComponent))
		return string.join(dataList, "")

	def compile(self, ttFont):
		if 'glyf' in ttFont:
			if ttFont.isLoaded('glyf') and ttFont.recalcBBoxes:
				self.recalc(ttFont)
		else:
			pass  # CFF
		self.numGlyphs = len(ttFont.getGlyphOrder())
		if self.tableVersion != 0x00005000:
			self.tableVersion = 0x00010000
		data = sstruct.pack(maxpFormat_0_5, self)
		if self.tableVersion == 0x00010000:
			data = data + sstruct.pack(maxpFormat_1_0_add, self)
		return data

	def compile(self, ttFont):
		panose = self.panose
		self.panose = sstruct.pack(panoseFormat, self.panose)
		if self.version == 0:
			data = sstruct.pack(OS2_format_0, self)
		elif self.version == 1:
			data = sstruct.pack(OS2_format_1, self)
		elif self.version in (2, 3, 4):
			data = sstruct.pack(OS2_format_2, self)
		else:
			from fontTools import ttLib
			raise ttLib.TTLibError("unknown format for OS/2 table: version %s" % self.version)
		self.panose = panose
		return data

	def test_incorrect_compressed_size(self):
		data = self.file.read(woff2DirectorySize)
		header = sstruct.unpack(woff2DirectoryFormat, data)
		header['totalCompressedSize'] = 0
		data = sstruct.pack(woff2DirectoryFormat, header)
		with self.assertRaises(brotli.error):
			WOFF2Reader(BytesIO(data + self.file.read()))

	def _calcMasterChecksum(self, directory):
		# calculate checkSumAdjustment
		tags = self.tables.keys()
		checksums = []
		for i in range(len(tags)):
			checksums.append(self.tables[tags[i]].checkSum)

		# TODO(behdad) I'm fairly sure the checksum for woff is not working correctly.
		# Haven't debugged.
		if self.DirectoryEntry != SFNTDirectoryEntry:
			# Create a SFNT directory for checksum calculation purposes
			self.searchRange, self.entrySelector, self.rangeShift = getSearchRange(self.numTables)
			directory = sstruct.pack(sfntDirectoryFormat, self)
			tables = self.tables.items()
			tables.sort()
			for tag, entry in tables:
				sfntEntry = SFNTDirectoryEntry()
				for item in ['tag', 'checkSum', 'offset', 'length']:
					setattr(sfntEntry, item, getattr(entry, item))
				directory = directory + sfntEntry.toString()

		directory_end = sfntDirectorySize + len(self.tables) * sfntDirectoryEntrySize
		assert directory_end == len(directory)

		checksums.append(calcChecksum(directory))
		checksum = sum(checksums) & 0xffffffff
		# BiboAfba!
		checksumadjustment = (0xB1B0AFBA - checksum) & 0xffffffff
		return checksumadjustment

 def _writeTableDirectory(self):
     if self.verbose:
         debugmsg("writing table directory")
     self.file.seek(woffHeaderSize)
     for tag, (index, entry, data) in sorted(self.tables.items()):
         entry = sstruct.pack(woffDirectoryEntryFormat, entry)
         self.file.write(entry)

	def compile(self, ttFont):
		self.numGMAPs = len(self.GMAPs)
		self.numGlyplets = len(self.glyphlets)
		GMAPoffsets = [0]*(self.numGMAPs + 1)
		glyphletOffsets = [0]*(self.numGlyplets + 1)

		dataList =[ sstruct.pack(GPKGFormat, self)]

		pos = len(dataList[0]) + (self.numGMAPs + 1)*4 + (self.numGlyplets + 1)*4
		GMAPoffsets[0] = pos
		for i in range(1, self.numGMAPs +1):
			pos += len(self.GMAPs[i-1])
			GMAPoffsets[i] = pos
		gmapArray = numpy.array(GMAPoffsets, numpy.uint32)
		if sys.byteorder <> "big":
			gmapArray = gmapArray.byteswap()
		dataList.append(gmapArray.tostring())

		glyphletOffsets[0] = pos
		for i in range(1, self.numGlyplets +1):
			pos += len(self.glyphlets[i-1])
			glyphletOffsets[i] = pos
		glyphletArray = numpy.array(glyphletOffsets, numpy.uint32)
		if sys.byteorder <> "big":
			glyphletArray = glyphletArray.byteswap()
		dataList.append(glyphletArray.tostring())
		dataList += self.GMAPs
		dataList += self.glyphlets
		data = "".join(dataList)
		return data

def calcHeadCheckSumAdjustment(flavor, tables):
    numTables = len(tables)
    # build the sfnt header
    searchRange, entrySelector, rangeShift = getSearchRange(numTables)
    sfntDirectoryData = dict(
        sfntVersion=flavor,
        numTables=numTables,
        searchRange=searchRange,
        entrySelector=entrySelector,
        rangeShift=rangeShift
    )
    # build the sfnt directory
    directory = sstruct.pack(sfntDirectoryFormat, sfntDirectoryData)
    for tag, entry in sorted(tables.items()):
        entry = tables[tag]
        sfntEntry = SFNTDirectoryEntry()
        sfntEntry.tag = tag
        sfntEntry.checkSum = entry["checkSum"]
        sfntEntry.offset = entry["offset"]
        sfntEntry.length = entry["length"]
        directory += sfntEntry.toString()
    # calculate the checkSumAdjustment
    checkSums = [entry["checkSum"] for entry in tables.values()]
    checkSums.append(calcChecksum(directory))
    checkSumAdjustment = sum(checkSums)
    checkSumAdjustment = (0xB1B0AFBA - checkSumAdjustment) & 0xffffffff
    # done
    return checkSumAdjustment

 def close(self):
     if self.numTables != len(self.tables):
         raise WOFFLibError("wrong number of tables; expected %d, found %d" % (self.numTables, len(self.tables)))
     # first, handle the checkSumAdjustment
     if self.recalculateHeadChecksum and "head" in self.tables:
         self._handleHeadChecksum()
     # check the table directory conformance
     for tag, (index, entry, data) in sorted(self.tables.items()):
         self._checkTableConformance(entry, data)
     # write the header
     header = sstruct.pack(woffHeaderFormat, self)
     self.file.seek(0)
     self.file.write(header)
     # update the directory offsets
     offset = woffHeaderSize + (woffDirectoryEntrySize * self.numTables)
     order = self._tableOrder()
     for tag in order:
         index, entry, data = self.tables[tag]
         entry.offset = offset
         offset += calc4BytePaddedLength(entry.compLength) # ensure byte alignment
     # write the directory
     self._writeTableDirectory()
     # write the table data
     self._writeTableData()
     # write the metadata
     self._writeMetadata()
     # write the private data
     self._writePrivateData()
     # write the header
     self._writeHeader()
     # go to the beginning of the file
     self.file.seek(0)

 def compile(self, ttFont):
     packed = sstruct.pack(DSIG_HeaderFormat, self)
     headers = [packed]
     offset = len(packed) + self.usNumSigs * sstruct.calcsize(DSIG_SignatureFormat)
     data = []
     for sigrec in self.signatureRecords:
         # first pack signature block
         sigrec.cbSignature = len(sigrec.pkcs7)
         packed = sstruct.pack(DSIG_SignatureBlockFormat, sigrec) + sigrec.pkcs7
         data.append(packed)
         # update redundant length field
         sigrec.ulLength = len(packed)
         # update running table offset
         sigrec.ulOffset = offset
         headers.append(sstruct.pack(DSIG_SignatureFormat, sigrec))
         offset += sigrec.ulLength
     return "".join(headers + data)

	def test_incorrect_file_size(self):
		data = self.file.read(woff2DirectorySize)
		header = sstruct.unpack(woff2DirectoryFormat, data)
		header['length'] -= 1
		data = sstruct.pack(woff2DirectoryFormat, header)
		with self.assertRaisesRegex(
				ttLib.TTLibError, "doesn't match the actual file size"):
			WOFF2Reader(BytesIO(data + self.file.read()))

	def compile(self, parentTable):
		data = sstruct.pack(METAStringRecordFormat, self)
		if parentTable.metaFlags == 0:
			datum = struct.pack(">H", self.offset)
		elif parentTable.metaFlags == 1:
			datum = struct.pack(">L", self.offset)
		data = data + datum
		return data

	def compile(self, ttFont):
		if 	self.UV == None:
			self.UV = 0
		nameLen =  len(self.name)
		if nameLen < 32:
			self.name = self.name + "\0"*(32 - nameLen)
		data = sstruct.pack(GMAPRecordFormat1, self)
		return data

	def compile(self, ttFont):
		sbixData = ""
		self.numSets = len(self.bitmapSets)
		sbixHeader = sstruct.pack(sbixHeaderFormat, self)
		
		# calculate offset to start of first bitmap set
		setOffset = sbixHeaderFormatSize + sbixBitmapSetOffsetFormatSize * self.numSets
		
		for si in sorted(self.bitmapSets.keys()):
			myBitmapSet = self.bitmapSets[si]
			myBitmapSet.compile(ttFont)
			# append offset to this bitmap set to table header
			myBitmapSet.offset = setOffset
			sbixHeader += sstruct.pack(sbixBitmapSetOffsetFormat, myBitmapSet)
			setOffset += len(myBitmapSet.data)
			sbixData += myBitmapSet.data
		
		return sbixHeader + sbixData

	def compile(self, ttFont):
		glyphIds = map(ttFont.getGlyphID, self.names)
		# Make sure all the ids are consecutive. This is required by Format 2.
		assert glyphIds == range(self.firstGlyphIndex, self.lastGlyphIndex+1), "Format 2 ids must be consecutive."
		self.imageDataOffset = min(zip(*self.locations)[0])

		dataList = [EblcIndexSubTable.compile(self, ttFont)]
		dataList.append(struct.pack(">L", self.imageSize))
		dataList.append(sstruct.pack(bigGlyphMetricsFormat, self.metrics))
		return string.join(dataList, "")