def read_index(sections, idx, codec):
table, cncx = OrderedDict(), CNCX([], codec)
data = sections[idx].raw
indx_header = parse_indx_header(data)
indx_count = indx_header['count']
if indx_header['ncncx'] > 0:
off = idx + indx_count + 1
cncx_records = [x.raw for x in sections[off:off+indx_header['ncncx']]]
cncx = CNCX(cncx_records, codec)
tag_section_start = indx_header['tagx']
control_byte_count, tags = parse_tagx_section(data[tag_section_start:])
read_variable_len_data(data, indx_header)
index_headers = []
for i in range(idx + 1, idx + 1 + indx_count):
# Index record
data = sections[i].raw
index_headers.append(parse_index_record(table, data, control_byte_count, tags, codec,
indx_header['ordt_map'], strict=True))
read_variable_len_data(data, index_headers[-1])
return table, cncx, indx_header, index_headers
def read_index(sections, idx, codec):
table, cncx = OrderedDict(), CNCX([], codec)
data = sections[idx].raw
indx_header = parse_indx_header(data)
indx_count = indx_header['count']
if indx_header['ncncx'] > 0:
off = idx + indx_count + 1
cncx_records = [x.raw for x in sections[off:off+indx_header['ncncx']]]
cncx = CNCX(cncx_records, codec)
tag_section_start = indx_header['tagx']
control_byte_count, tags = parse_tagx_section(data[tag_section_start:])
read_variable_len_data(data, indx_header)
index_headers = []
for i in range(idx + 1, idx + 1 + indx_count):
# Index record
data = sections[i].raw
index_headers.append(parse_index_record(table, data, control_byte_count, tags, codec,
indx_header['ordt_map'], strict=True))
read_variable_len_data(data, index_headers[-1])
return table, cncx, indx_header, index_headers
def __init__(self, record):
self.record = record
raw = self.record.raw
# open('/t/index_header.bin', 'wb').write(raw)
if raw[:4] != b'INDX':
raise ValueError('Invalid Primary Index Record')
self.header_length, = struct.unpack('>I', raw[4:8])
self.unknown1 = raw[8:12]
self.header_type, = struct.unpack('>I', raw[12:16])
self.index_type, = struct.unpack('>I', raw[16:20])
self.index_type_desc = {0: 'normal', 2:
'inflection', 6: 'calibre'}.get(self.index_type, 'unknown')
self.idxt_start, = struct.unpack('>I', raw[20:24])
self.index_count, = struct.unpack('>I', raw[24:28])
self.index_encoding_num, = struct.unpack('>I', raw[28:32])
self.index_encoding = {65001: 'utf-8', 1252:
'cp1252'}.get(self.index_encoding_num, 'unknown')
if self.index_encoding == 'unknown':
raise ValueError(
'Unknown index encoding: %d'%self.index_encoding_num)
self.possibly_language = raw[32:36]
self.num_index_entries, = struct.unpack('>I', raw[36:40])
self.ordt_start, = struct.unpack('>I', raw[40:44])
self.ligt_start, = struct.unpack('>I', raw[44:48])
self.num_of_ligt_entries, = struct.unpack('>I', raw[48:52])
self.num_of_cncx_blocks, = struct.unpack('>I', raw[52:56])
self.unknown2 = raw[56:180]
self.tagx_offset, = struct.unpack(b'>I', raw[180:184])
if self.tagx_offset != self.header_length:
raise ValueError('TAGX offset and header length disagree')
self.unknown3 = raw[184:self.header_length]
tagx = raw[self.header_length:]
if not tagx.startswith(b'TAGX'):
raise ValueError('Invalid TAGX section')
self.tagx_header_length, = struct.unpack('>I', tagx[4:8])
self.tagx_control_byte_count, = struct.unpack('>I', tagx[8:12])
self.tagx_entries = [TagX(*x) for x in parse_tagx_section(tagx)[1]]
if self.tagx_entries and not self.tagx_entries[-1].is_eof:
raise ValueError('TAGX last entry is not EOF')
idxt0_pos = self.header_length+self.tagx_header_length
last_num, consumed = decode_hex_number(raw[idxt0_pos:])
count_pos = idxt0_pos + consumed
self.ncx_count, = struct.unpack(b'>H', raw[count_pos:count_pos+2])
self.last_entry = last_num
if last_num != self.ncx_count - 1:
raise ValueError('Last id number in the NCX != NCX count - 1')
# There may be some alignment zero bytes between the end of the idxt0
# and self.idxt_start
idxt = raw[self.idxt_start:]
if idxt[:4] != b'IDXT':
raise ValueError('Invalid IDXT header')
length_check, = struct.unpack(b'>H', idxt[4:6])
if length_check != self.header_length + self.tagx_header_length:
raise ValueError('Length check failed')
def __init__(self, record):
self.record = record
raw = self.record.raw
# open('/t/index_header.bin', 'wb').write(raw)
if raw[:4] != b'INDX':
raise ValueError('Invalid Primary Index Record')
self.header_length, = struct.unpack('>I', raw[4:8])
self.unknown1 = raw[8:12]
self.header_type, = struct.unpack('>I', raw[12:16])
self.index_type, = struct.unpack('>I', raw[16:20])
self.index_type_desc = {0: 'normal', 2:
'inflection', 6: 'calibre'}.get(self.index_type, 'unknown')
self.idxt_start, = struct.unpack('>I', raw[20:24])
self.index_count, = struct.unpack('>I', raw[24:28])
self.index_encoding_num, = struct.unpack('>I', raw[28:32])
self.index_encoding = {65001: 'utf-8', 1252:
'cp1252'}.get(self.index_encoding_num, 'unknown')
if self.index_encoding == 'unknown':
raise ValueError(
'Unknown index encoding: %d'%self.index_encoding_num)
self.possibly_language = raw[32:36]
self.num_index_entries, = struct.unpack('>I', raw[36:40])
self.ordt_start, = struct.unpack('>I', raw[40:44])
self.ligt_start, = struct.unpack('>I', raw[44:48])
self.num_of_ligt_entries, = struct.unpack('>I', raw[48:52])
self.num_of_cncx_blocks, = struct.unpack('>I', raw[52:56])
self.unknown2 = raw[56:180]
self.tagx_offset, = struct.unpack(b'>I', raw[180:184])
if self.tagx_offset != self.header_length:
raise ValueError('TAGX offset and header length disagree')
self.unknown3 = raw[184:self.header_length]
tagx = raw[self.header_length:]
if not tagx.startswith(b'TAGX'):
raise ValueError('Invalid TAGX section')
self.tagx_header_length, = struct.unpack('>I', tagx[4:8])
self.tagx_control_byte_count, = struct.unpack('>I', tagx[8:12])
self.tagx_entries = [TagX(*x) for x in parse_tagx_section(tagx)[1]]
if self.tagx_entries and not self.tagx_entries[-1].is_eof:
raise ValueError('TAGX last entry is not EOF')
idxt0_pos = self.header_length+self.tagx_header_length
last_num, consumed = decode_hex_number(raw[idxt0_pos:])
count_pos = idxt0_pos + consumed
self.ncx_count, = struct.unpack(b'>H', raw[count_pos:count_pos+2])
self.last_entry = last_num
if last_num != self.ncx_count - 1:
raise ValueError('Last id number in the NCX != NCX count - 1')
# There may be some alignment zero bytes between the end of the idxt0
# and self.idxt_start
idxt = raw[self.idxt_start:]
if idxt[:4] != b'IDXT':
raise ValueError('Invalid IDXT header')
length_check, = struct.unpack(b'>H', idxt[4:6])
if length_check != self.header_length + self.tagx_header_length:
raise ValueError('Length check failed')
