def getNamedDestRoot(self):
root = self.getObject(self._root)
if '/Names' in root and isinstance(root['/Names'], DictionaryObject):
names = root['/Names']
idnum = self._objects.index(names) + 1
namesRef = IndirectObject(idnum, 0, self)
assert namesRef.getObject() == names
if '/Dests' in names and isinstance(
names['/Dests'], DictionaryObject):
dests = names['/Dests']
idnum = self._objects.index(dests) + 1
destsRef = IndirectObject(idnum, 0, self)
assert destsRef.getObject() == dests
if '/Names' in dests:
nd = dests['/Names']
else:
nd = ArrayObject()
dests[NameObject('/Names')] = nd
else:
dests = DictionaryObject()
destsRef = self._addObject(dests)
names[NameObject('/Dests')] = destsRef
nd = ArrayObject()
dests[NameObject('/Names')] = nd
else:
names = DictionaryObject()
namesRef = self._addObject(names)
root[NameObject('/Names')] = namesRef
dests = DictionaryObject()
destsRef = self._addObject(dests)
names[NameObject('/Dests')] = destsRef
nd = ArrayObject()
dests[NameObject('/Names')] = nd
return nd
def getOutlineRoot(self):
root = self.getObject(self._root)
if '/Outlines' in root:
outline = root['/Outlines']
idnum = self._objects.index(outline) + 1
outlineRef = IndirectObject(idnum, 0, self)
assert outlineRef.getObject() == outline
else:
outline = TreeObject()
outline.update({})
outlineRef = self._addObject(outline)
root[NameObject('/Outlines')] = outlineRef
return outline
def getOutlineRoot(self):
root = self.getObject(self._root)
if '/Outlines' in root:
outline = root['/Outlines']
idnum = self._objects.index(outline) + 1
outlineRef = IndirectObject(idnum, 0, self)
assert outlineRef.getObject() == outline
else:
outline = TreeObject()
outline.update({})
outlineRef = self._addObject(outline)
root[NameObject('/Outlines')] = outlineRef
return outline
def getNamedDestRoot(self):
root = self.getObject(self._root)
if '/Names' in root and isinstance(root['/Names'], DictionaryObject):
names = root['/Names']
idnum = self._objects.index(names) + 1
namesRef = IndirectObject(idnum, 0, self)
assert namesRef.getObject() == names
if '/Dests' in names and isinstance(names['/Dests'],
DictionaryObject):
dests = names['/Dests']
idnum = self._objects.index(dests) + 1
destsRef = IndirectObject(idnum, 0, self)
assert destsRef.getObject() == dests
if '/Names' in dests:
nd = dests['/Names']
else:
nd = ArrayObject()
dests[NameObject('/Names')] = nd
else:
dests = DictionaryObject()
destsRef = self._addObject(dests)
names[NameObject('/Dests')] = destsRef
nd = ArrayObject()
dests[NameObject('/Names')] = nd
else:
names = DictionaryObject()
namesRef = self._addObject(names)
root[NameObject('/Names')] = namesRef
dests = DictionaryObject()
destsRef = self._addObject(dests)
names[NameObject('/Dests')] = destsRef
nd = ArrayObject()
dests[NameObject('/Names')] = nd
return nd
def _sweepIndirectReferences(self, externMap, data):
if isinstance(data, DictionaryObject):
for key, value in data.items():
value = self._sweepIndirectReferences(externMap, value)
if isinstance(value, StreamObject):
# a dictionary value is a stream. streams must be indirect
# objects, so we need to change this value.
value = self._addObject(value)
data[key] = value
return data
elif isinstance(data, ArrayObject):
for i in range(len(data)):
value = self._sweepIndirectReferences(externMap, data[i])
if isinstance(value, StreamObject):
# an array value is a stream. streams must be indirect
# objects, so we need to change this value
value = self._addObject(value)
data[i] = value
return data
elif isinstance(data, IndirectObject):
# internal indirect references are fine
if data.pdf == self:
if data.idnum in self.stack:
return data
else:
self.stack.append(data.idnum)
realdata = self.getObject(data)
self._sweepIndirectReferences(externMap, realdata)
self.stack.pop()
return data
else:
newobj = externMap.get(data.pdf,
{}).get(data.generation,
{}).get(data.idnum, None)
if newobj is None:
newobj = data.pdf.getObject(data)
self._objects.append(None) # placeholder
idnum = len(self._objects)
newobj_ido = IndirectObject(idnum, 0, self)
externMap.setdefault(data.pdf, {})
externMap[data.pdf].setdefault(data.generation, {})
externMap[data.pdf][data.generation][data.idnum] = \
newobj_ido
newobj = self._sweepIndirectReferences(externMap, newobj)
self._objects[idnum - 1] = newobj
return newobj_ido
return newobj
else:
return data
def _addObject(self, obj):
self._objects.append(obj)
return IndirectObject(len(self._objects), 0, self)
def getReference(self, obj):
idnum = self._objects.index(obj) + 1
ref = IndirectObject(idnum, 0, self)
assert ref.getObject() == obj
return ref
def write(self, stream):
externalReferenceMap = {}
# PDF objects sometimes have circular references to their /Page objects
# inside their object tree (for example, annotations). Those will be
# indirect references to objects that we've recreated in this PDF. To
# address this problem, PageObject's store their original object
# reference number, and we add it to the external reference map before
# we sweep for indirect references. This forces self-page-referencing
# trees to reference the correct new object location, rather than
# copying in a new copy of the page object.
for objIndex in xrange(len(self._objects)):
obj = self._objects[objIndex]
if isinstance(obj, PageObject) and obj.indirectRef is not None:
data = obj.indirectRef
externalReferenceMap.setdefault(data.pdf, {})
externalReferenceMap[data.pdf].setdefault(data.generation, {})
externalReferenceMap[data.pdf][data.generation][data.idnum] = \
IndirectObject(objIndex + 1, 0, self)
self.stack = []
self._sweepIndirectReferences(externalReferenceMap, self._root)
del self.stack
# Begin writing:
object_positions = []
stream.write(self._header + b_("\n"))
for i in range(len(self._objects)):
idnum = (i + 1)
obj = self._objects[i]
object_positions.append(stream.tell())
stream.write(b_(str(idnum) + " 0 obj\n"))
key = None
if hasattr(self, "_encrypt") and idnum != self._encrypt.idnum:
pack1 = struct.pack("<i", i + 1)[:3]
pack2 = struct.pack("<i", 0)[:2]
key = self._encrypt_key + pack1 + pack2
assert len(key) == (len(self._encrypt_key) + 5)
md5_hash = md5(key).digest()
key = md5_hash[:min(16, len(self._encrypt_key) + 5)]
if obj is not None:
obj.writeToStream(stream, key)
stream.write(b_("\nendobj\n"))
# xref table
xref_location = stream.tell()
stream.write(b_("xref\n"))
stream.write(b_("0 %s\n" % (len(self._objects) + 1)))
stream.write(b_("%010d %05d f \n" % (0, 65535)))
for offset in object_positions:
stream.write(b_("%010d %05d n \n" % (offset, 0)))
# trailer
stream.write(b_("trailer\n"))
trailer = DictionaryObject()
trailer.update({
NameObject("/Size"):
NumberObject(len(self._objects) + 1),
NameObject("/Root"):
self._root,
NameObject("/Info"):
self._info
})
if hasattr(self, "_ID"):
trailer[NameObject("/ID")] = self._ID
if hasattr(self, "_encrypt"):
trailer[NameObject("/Encrypt")] = self._encrypt
trailer.writeToStream(stream, None)
# eof
stream.write(b_("\nstartxref\n%s\n%%%%EOF\n" % (xref_location)))
def getObject(self, indirectReference):
retval = self.resolvedObjects.get(indirectReference.generation,
{}).get(indirectReference.idnum,
None)
if retval is not None:
return retval
if indirectReference.generation == 0 \
and indirectReference.idnum in self.xref_objStm:
# indirect reference to object in object stream
# read the entire object stream into memory
stmnum, idx = self.xref_objStm[indirectReference.idnum]
objStm = IndirectObject(stmnum, 0, self).getObject()
assert objStm['/Type'] == '/ObjStm'
assert idx < objStm['/N']
streamData = StringIO(objStm.getData())
for i in range(objStm['/N']):
objnum = NumberObject.readFromStream(streamData)
readNonWhitespace(streamData)
streamData.seek(-1, 1)
offset = NumberObject.readFromStream(streamData)
readNonWhitespace(streamData)
streamData.seek(-1, 1)
t = streamData.tell()
streamData.seek(objStm['/First']+offset, 0)
obj = readObject(streamData, self)
self.resolvedObjects[0][objnum] = obj
streamData.seek(t, 0)
return self.resolvedObjects[0][indirectReference.idnum]
if indirectReference.idnum \
not in self.xref[indirectReference.generation]:
warnings.warn("Object %d %d not defined." % (
indirectReference.idnum, indirectReference.generation),
utils.PdfReadWarning)
return None
start = self.xref[indirectReference.generation][
indirectReference.idnum]
self.stream.seek(start, 0)
idnum, generation = self.readObjectHeader(self.stream)
try:
assert idnum == indirectReference.idnum
except AssertionError:
if self.xrefIndex:
# Xref table probably had bad indexes due to not
# being zero-indexed
if self.strict:
raise utils.PdfReadError(
"Expected object ID (%d %d) does "
"not match actual (%d %d); xref "
"table not zero-indexed." % (
indirectReference.idnum,
indirectReference.generation,
idnum,
generation))
else:
# should not happen since the xref table is corrected in
# non-strict mode
pass
else: # some other problem
raise utils.PdfReadError("Expected object ID (%d %d) does not "
" match actual (%d %d)." % (
indirectReference.idnum,
indirectReference.generation,
idnum, generation))
assert generation == indirectReference.generation
retval = readObject(self.stream, self)
# override encryption is used for the /Encrypt dictionary
if not self._override_encryption and self.isEncrypted:
# if we don't have the encryption key:
if not hasattr(self, '_decryption_key'):
raise Exception("file has not been decrypted")
# otherwise, decrypt here...
pack1 = struct.pack("<i", indirectReference.idnum)[:3]
pack2 = struct.pack("<i", indirectReference.generation)[:2]
key = self._decryption_key + pack1 + pack2
assert len(key) == (len(self._decryption_key) + 5)
md5_hash = md5(key).digest()
key = md5_hash[:min(16, len(self._decryption_key) + 5)]
retval = self._decryptObject(retval, key)
self.cacheIndirectObject(generation, idnum, retval)
return retval
def getObject(self, indirectReference):
retval = self.resolvedObjects.get(indirectReference.generation,
{}).get(indirectReference.idnum,
None)
if retval is not None:
return retval
if indirectReference.generation == 0 \
and indirectReference.idnum in self.xref_objStm:
# indirect reference to object in object stream
# read the entire object stream into memory
stmnum, idx = self.xref_objStm[indirectReference.idnum]
objStm = IndirectObject(stmnum, 0, self).getObject()
assert objStm['/Type'] == '/ObjStm'
assert idx < objStm['/N']
streamData = StringIO(objStm.getData())
for i in range(objStm['/N']):
objnum = NumberObject.readFromStream(streamData)
readNonWhitespace(streamData)
streamData.seek(-1, 1)
offset = NumberObject.readFromStream(streamData)
readNonWhitespace(streamData)
streamData.seek(-1, 1)
t = streamData.tell()
streamData.seek(objStm['/First'] + offset, 0)
obj = readObject(streamData, self)
self.resolvedObjects[0][objnum] = obj
streamData.seek(t, 0)
return self.resolvedObjects[0][indirectReference.idnum]
if indirectReference.idnum \
not in self.xref[indirectReference.generation]:
warnings.warn(
"Object %d %d not defined." %
(indirectReference.idnum, indirectReference.generation),
utils.PdfReadWarning)
return None
start = self.xref[indirectReference.generation][
indirectReference.idnum]
self.stream.seek(start, 0)
idnum, generation = self.readObjectHeader(self.stream)
try:
assert idnum == indirectReference.idnum
except AssertionError:
if self.xrefIndex:
# Xref table probably had bad indexes due to not
# being zero-indexed
if self.strict:
raise utils.PdfReadError(
"Expected object ID (%d %d) does "
"not match actual (%d %d); xref "
"table not zero-indexed." %
(indirectReference.idnum, indirectReference.generation,
idnum, generation))
else:
# should not happen since the xref table is corrected in
# non-strict mode
pass
else: # some other problem
raise utils.PdfReadError(
"Expected object ID (%d %d) does not "
" match actual (%d %d)." %
(indirectReference.idnum, indirectReference.generation,
idnum, generation))
assert generation == indirectReference.generation
retval = readObject(self.stream, self)
# override encryption is used for the /Encrypt dictionary
if not self._override_encryption and self.isEncrypted:
# if we don't have the encryption key:
if not hasattr(self, '_decryption_key'):
raise Exception("file has not been decrypted")
# otherwise, decrypt here...
pack1 = struct.pack("<i", indirectReference.idnum)[:3]
pack2 = struct.pack("<i", indirectReference.generation)[:2]
key = self._decryption_key + pack1 + pack2
assert len(key) == (len(self._decryption_key) + 5)
md5_hash = md5(key).digest()
key = md5_hash[:min(16, len(self._decryption_key) + 5)]
retval = self._decryptObject(retval, key)
self.cacheIndirectObject(generation, idnum, retval)
return retval
def getReference(self, obj):
idnum = self._objects.index(obj) + 1
ref = IndirectObject(idnum, 0, self)
assert ref.getObject() == obj
return ref