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

124 lines
4.3 KiB
Python

"""
Tar archive parser.
Author: Victor Stinner
"""
from hachoir_parser import Parser
from hachoir_core.field import (FieldSet,
Enum, UInt8, SubFile, String, NullBytes)
from hachoir_core.tools import humanFilesize, paddingSize, timestampUNIX
from hachoir_core.endian import BIG_ENDIAN
import re
class FileEntry(FieldSet):
type_name = {
# 48 is "0", 49 is "1", ...
0: u"Normal disk file (old format)",
48: u"Normal disk file",
49: u"Link to previously dumped file",
50: u"Symbolic link",
51: u"Character special file",
52: u"Block special file",
53: u"Directory",
54: u"FIFO special file",
55: u"Contiguous file"
}
def getOctal(self, name):
return self.octal2int(self[name].value)
def getDatetime(self):
"""
Create modification date as Unicode string, may raise ValueError.
"""
timestamp = self.getOctal("mtime")
return timestampUNIX(timestamp)
def createFields(self):
yield String(self, "name", 100, "Name", strip="\0", charset="ISO-8859-1")
yield String(self, "mode", 8, "Mode", strip=" \0", charset="ASCII")
yield String(self, "uid", 8, "User ID", strip=" \0", charset="ASCII")
yield String(self, "gid", 8, "Group ID", strip=" \0", charset="ASCII")
yield String(self, "size", 12, "Size", strip=" \0", charset="ASCII")
yield String(self, "mtime", 12, "Modification time", strip=" \0", charset="ASCII")
yield String(self, "check_sum", 8, "Check sum", strip=" \0", charset="ASCII")
yield Enum(UInt8(self, "type", "Type"), self.type_name)
yield String(self, "lname", 100, "Link name", strip=" \0", charset="ISO-8859-1")
yield String(self, "magic", 8, "Magic", strip=" \0", charset="ASCII")
yield String(self, "uname", 32, "User name", strip=" \0", charset="ISO-8859-1")
yield String(self, "gname", 32, "Group name", strip=" \0", charset="ISO-8859-1")
yield String(self, "devmajor", 8, "Dev major", strip=" \0", charset="ASCII")
yield String(self, "devminor", 8, "Dev minor", strip=" \0", charset="ASCII")
yield NullBytes(self, "padding", 167, "Padding (zero)")
filesize = self.getOctal("size")
if filesize:
yield SubFile(self, "content", filesize, filename=self["name"].value)
size = paddingSize(self.current_size//8, 512)
if size:
yield NullBytes(self, "padding_end", size, "Padding (512 align)")
def convertOctal(self, chunk):
return self.octal2int(chunk.value)
def isEmpty(self):
return self["name"].value == ""
def octal2int(self, text):
try:
return int(text, 8)
except ValueError:
return 0
def createDescription(self):
if self.isEmpty():
desc = "(terminator, empty header)"
else:
filename = self["name"].value
filesize = humanFilesize(self.getOctal("size"))
desc = "(%s: %s, %s)" % \
(filename, self["type"].display, filesize)
return "Tar File " + desc
class TarFile(Parser):
endian = BIG_ENDIAN
PARSER_TAGS = {
"id": "tar",
"category": "archive",
"file_ext": ("tar",),
"mime": (u"application/x-tar", u"application/x-gtar"),
"min_size": 512*8,
"magic": (("ustar \0", 257*8),),
"subfile": "skip",
"description": "TAR archive",
}
_sign = re.compile("ustar *\0|[ \0]*$")
def validate(self):
if not self._sign.match(self.stream.readBytes(257*8, 8)):
return "Invalid magic number"
if self[0].name == "terminator":
return "Don't contain any file"
try:
int(self["file[0]/uid"].value, 8)
int(self["file[0]/gid"].value, 8)
int(self["file[0]/size"].value, 8)
except ValueError:
return "Invalid file size"
return True
def createFields(self):
while not self.eof:
field = FileEntry(self, "file[]")
if field.isEmpty():
yield NullBytes(self, "terminator", 512)
break
yield field
if self.current_size < self._size:
yield self.seekBit(self._size, "end")
def createContentSize(self):
return self["terminator"].address + self["terminator"].size