def readObjectHeader(self, stream): # Should never be necessary to read out whitespace, since the # cross-reference table should put us in the right spot to read the # object header. In reality... some files have stupid cross reference # tables that are off by whitespace bytes. extra = False utils.skipOverComment(stream) extra |= utils.skipOverWhitespace(stream) stream.seek(-1, 1) idnum = readUntilWhitespace(stream) extra |= utils.skipOverWhitespace(stream) stream.seek(-1, 1) generation = readUntilWhitespace(stream) stream.read(3) readNonWhitespace(stream) stream.seek(-1, 1) if (extra and self.strict): #not a fatal error warnings.warn( "Superfluous whitespace found in " "object header %s %s" % (idnum, generation), utils.PdfReadWarning) return int(idnum), int(generation)
def readFromStream(stream, pdf): debug = False tmp = stream.read(2) if tmp != b_("<<"): raise utils.PdfReadError( "Dictionary read error at byte %s: stream must begin with '<<'" % utils.hexStr(stream.tell())) data = {} while True: tok = readNonWhitespace(stream) if tok == b_('\x00'): continue elif tok == b_('%'): stream.seek(-1, 1) skipOverComment(stream) continue if not tok: # stream has truncated prematurely raise PdfStreamError("Stream has ended unexpectedly") if debug: print(("Tok:", tok)) if tok == b_(">"): stream.read(1) break stream.seek(-1, 1) key = readObject(stream, pdf) tok = readNonWhitespace(stream) stream.seek(-1, 1) value = readObject(stream, pdf) if not data.get(key): data[key] = value elif pdf.strict: # multiple definitions of key not permitted raise utils.PdfReadError("Multiple definitions in dictionary at byte %s for key %s" \ % (utils.hexStr(stream.tell()), key)) else: warnings.warn("Multiple definitions in dictionary at byte %s for key %s" \ % (utils.hexStr(stream.tell()), key), utils.PdfReadWarning) pos = stream.tell() s = readNonWhitespace(stream) if s == b_('s') and stream.read(5) == b_('tream'): eol = stream.read(1) # odd PDF file output has spaces after 'stream' keyword but before EOL. # patch provided by Danial Sandler while eol == b_(' '): eol = stream.read(1) assert eol in (b_("\n"), b_("\r")) if eol == b_("\r"): # read \n after if stream.read(1) != b_('\n'): stream.seek(-1, 1) # this is a stream object, not a dictionary assert "/Length" in data length = data["/Length"] if debug: print(data) if isinstance(length, IndirectObject): t = stream.tell() length = pdf.getObject(length) stream.seek(t, 0) data["__streamdata__"] = stream.read(length) if debug: print("here") #if debug: print(binascii.hexlify(data["__streamdata__"])) e = readNonWhitespace(stream) ndstream = stream.read(8) if (e + ndstream) != b_("endstream"): # (sigh) - the odd PDF file has a length that is too long, so # we need to read backwards to find the "endstream" ending. # ReportLab (unknown version) generates files with this bug, # and Python users into PDF files tend to be our audience. # we need to do this to correct the streamdata and chop off # an extra character. pos = stream.tell() stream.seek(-10, 1) end = stream.read(9) if end == b_("endstream"): # we found it by looking back one character further. data["__streamdata__"] = data["__streamdata__"][:-1] else: if debug: print(("E", e, ndstream, debugging.toHex(end))) stream.seek(pos, 0) raise utils.PdfReadError( "Unable to find 'endstream' marker after stream at byte %s." % utils.hexStr(stream.tell())) else: stream.seek(pos, 0) if "__streamdata__" in data: return StreamObject.initializeFromDictionary(data) else: retval = DictionaryObject() retval.update(data) return retval
def readFromStream(stream, pdf): debug = False tmp = stream.read(2) if tmp != b_("<<"): raise utils.PdfReadError("Dictionary read error at byte %s: stream must begin with '<<'" % utils.hexStr(stream.tell())) data = {} while True: tok = readNonWhitespace(stream) if tok == b_('\x00'): continue elif tok == b_('%'): stream.seek(-1, 1) skipOverComment(stream) continue if not tok: # stream has truncated prematurely raise PdfStreamError("Stream has ended unexpectedly") if debug: print(("Tok:", tok)) if tok == b_(">"): stream.read(1) break stream.seek(-1, 1) key = readObject(stream, pdf) tok = readNonWhitespace(stream) stream.seek(-1, 1) value = readObject(stream, pdf) if not data.get(key): data[key] = value elif pdf.strict: # multiple definitions of key not permitted raise utils.PdfReadError("Multiple definitions in dictionary at byte %s for key %s" \ % (utils.hexStr(stream.tell()), key)) else: warnings.warn("Multiple definitions in dictionary at byte %s for key %s" \ % (utils.hexStr(stream.tell()), key), utils.PdfReadWarning) pos = stream.tell() s = readNonWhitespace(stream) if s == b_('s') and stream.read(5) == b_('tream'): eol = stream.read(1) # odd PDF file output has spaces after 'stream' keyword but before EOL. # patch provided by Danial Sandler while eol == b_(' '): eol = stream.read(1) assert eol in (b_("\n"), b_("\r")) if eol == b_("\r"): # read \n after if stream.read(1) != b_('\n'): stream.seek(-1, 1) # this is a stream object, not a dictionary assert "/Length" in data length = data["/Length"] if debug: print(data) if isinstance(length, IndirectObject): t = stream.tell() length = pdf.getObject(length) stream.seek(t, 0) data["__streamdata__"] = stream.read(length) if debug: print("here") #if debug: print(binascii.hexlify(data["__streamdata__"])) e = readNonWhitespace(stream) ndstream = stream.read(8) if (e + ndstream) != b_("endstream"): # (sigh) - the odd PDF file has a length that is too long, so # we need to read backwards to find the "endstream" ending. # ReportLab (unknown version) generates files with this bug, # and Python users into PDF files tend to be our audience. # we need to do this to correct the streamdata and chop off # an extra character. pos = stream.tell() stream.seek(-10, 1) end = stream.read(9) if end == b_("endstream"): # we found it by looking back one character further. data["__streamdata__"] = data["__streamdata__"][:-1] else: if debug: print(("E", e, ndstream, debugging.toHex(end))) stream.seek(pos, 0) raise utils.PdfReadError("Unable to find 'endstream' marker after stream at byte %s." % utils.hexStr(stream.tell())) else: stream.seek(pos, 0) if "__streamdata__" in data: return StreamObject.initializeFromDictionary(data) else: retval = DictionaryObject() retval.update(data) return retval
def readObjectHeader(self, stream): # Should never be necessary to read out whitespace, since the # cross-reference table should put us in the right spot to read the # object header. In reality... some files have stupid cross reference # tables that are off by whitespace bytes. extra = False utils.skipOverComment(stream) extra |= utils.skipOverWhitespace(stream) stream.seek(-1, 1) idnum = readUntilWhitespace(stream) extra |= utils.skipOverWhitespace(stream) stream.seek(-1, 1) generation = readUntilWhitespace(stream) stream.read(3) readNonWhitespace(stream) stream.seek(-1, 1) if (extra and self.strict): #not a fatal error warnings.warn("Superfluous whitespace found in " "object header %s %s" % (idnum, generation), utils.PdfReadWarning) return int(idnum), int(generation)