SickGear/lib/hachoir_parser/archive/mozilla_ar.py
2015-08-20 16:48:28 +01:00

60 lines
2.3 KiB
Python

"""MAR (Mozilla ARchive) parser
Author: Robert Xiao
Creation date: July 10, 2007
"""
from hachoir_core.endian import BIG_ENDIAN
from hachoir_core.field import (RootSeekableFieldSet, FieldSet,
String, CString, UInt32, RawBytes)
from hachoir_core.text_handler import displayHandler, filesizeHandler
from hachoir_core.tools import humanUnixAttributes
from hachoir_parser import HachoirParser
class IndexEntry(FieldSet):
def createFields(self):
yield UInt32(self, "offset", "Offset in bytes relative to start of archive")
yield filesizeHandler(UInt32(self, "length", "Length in bytes"))
yield displayHandler(UInt32(self, "flags"), humanUnixAttributes)
yield CString(self, "name", "Filename (byte array)")
def createDescription(self):
return 'File %s, Size %s, Mode %s'%(
self["name"].display, self["length"].display, self["flags"].display)
class MozillaArchive(HachoirParser, RootSeekableFieldSet):
MAGIC = "MAR1"
PARSER_TAGS = {
"id": "mozilla_ar",
"category": "archive",
"file_ext": ("mar",),
"min_size": (8+4+13)*8, # Header, Index Header, 1 Index Entry
"magic": ((MAGIC, 0),),
"description": "Mozilla Archive",
}
endian = BIG_ENDIAN
def __init__(self, stream, **args):
RootSeekableFieldSet.__init__(self, None, "root", stream, None, stream.askSize(self))
HachoirParser.__init__(self, stream, **args)
def validate(self):
if self.stream.readBytes(0, 4) != self.MAGIC:
return "Invalid magic"
return True
def createFields(self):
yield String(self, "magic", 4, "File signature (MAR1)", charset="ASCII")
yield UInt32(self, "index_offset", "Offset to index relative to file start")
self.seekByte(self["index_offset"].value, False)
yield UInt32(self, "index_size", "size of index in bytes")
current_index_size = 0 # bytes
while current_index_size < self["index_size"].value:
# plus 4 compensates for index_size
self.seekByte(self["index_offset"].value + current_index_size + 4, False)
entry = IndexEntry(self, "index_entry[]")
yield entry
current_index_size += entry.size // 8
self.seekByte(entry["offset"].value, False)
yield RawBytes(self, "file[]", entry["length"].value)