Module refinery.units.formats.archive.xtgz

Expand source code Browse git 
from __future__ import annotations

from gzip import GzipFile, FEXTRA, FNAME
from datetime import datetime
from pathlib import Path

from refinery.units.formats.archive import ArchiveUnit
from refinery.lib.structures import Struct, StructReader, StreamDetour
from refinery.lib.meta import metavars


class GzipHeader(Struct):
    MAGIC = B'\x1F\x8B'

    def __init__(self, reader: StructReader):
        unpacker = GzipFile(fileobj=reader)
        with StreamDetour(reader, 0):
            self.magic = reader.read(2)
            self.method, self.flags, self.mtime = reader.read_struct('BBIxx')
            self.extra = None
            self.name = None
            if self.flags & FEXTRA:
                self.extra = reader.read(reader.u16())
            if self.flags & FNAME:
                self.name = reader.read_c_string().decode('latin1')
        self.data = unpacker.read()


class xtgz(ArchiveUnit):
    """
    Extract a file from a GZip archive.
    """
    def unpack(self, data: bytearray):
        archive = GzipHeader(data)
        path = archive.name
        date = archive.mtime
        date = date and datetime.fromtimestamp(date) or None
        if path is None:
            try:
                meta = metavars(data)
                path = Path(meta['path'])
            except KeyError:
                path = 'ungz'
            else:
                self.log_warn(path)
                suffix = path.suffix
                if suffix.lower() == '.gz':
                    path = path.with_suffix('')
                else:
                    path = path.with_suffix(F'{suffix}.ungz')
                path = path.as_posix()
        yield self._pack(path, date, archive.data)

    @classmethod
    def handles(cls, data: bytearray) -> bool:
        return data.startswith(B'\x1F\x8B')

Classes

class GzipHeader (reader)

A class to parse structured data. A Struct class can be instantiated as follows:

foo = Struct(data, bar=29)

The initialization routine of the structure will be called with a single argument reader. If the object data is already a StructReader, then it will be passed as reader. Otherwise, the argument will be wrapped in a StructReader. Additional arguments to the struct are passed through.

Expand source code Browse git 
class GzipHeader(Struct):
    MAGIC = B'\x1F\x8B'

    def __init__(self, reader: StructReader):
        unpacker = GzipFile(fileobj=reader)
        with StreamDetour(reader, 0):
            self.magic = reader.read(2)
            self.method, self.flags, self.mtime = reader.read_struct('BBIxx')
            self.extra = None
            self.name = None
            if self.flags & FEXTRA:
                self.extra = reader.read(reader.u16())
            if self.flags & FNAME:
                self.name = reader.read_c_string().decode('latin1')
        self.data = unpacker.read()

Ancestors

Class variables

var MAGIC
class xtgz (*paths, list=False, join_path=False, drop_path=False, fuzzy=0, exact=False, regex=False, path=b'path', date=b'date', pwd=b'')

Extract a file from a GZip archive.

Expand source code Browse git 
class xtgz(ArchiveUnit):
    """
    Extract a file from a GZip archive.
    """
    def unpack(self, data: bytearray):
        archive = GzipHeader(data)
        path = archive.name
        date = archive.mtime
        date = date and datetime.fromtimestamp(date) or None
        if path is None:
            try:
                meta = metavars(data)
                path = Path(meta['path'])
            except KeyError:
                path = 'ungz'
            else:
                self.log_warn(path)
                suffix = path.suffix
                if suffix.lower() == '.gz':
                    path = path.with_suffix('')
                else:
                    path = path.with_suffix(F'{suffix}.ungz')
                path = path.as_posix()
        yield self._pack(path, date, archive.data)

    @classmethod
    def handles(cls, data: bytearray) -> bool:
        return data.startswith(B'\x1F\x8B')

Ancestors

Subclasses

Class variables

var required_dependencies
var optional_dependencies
var console
var reverse

Methods

def unpack(self, data)
Expand source code Browse git 
def unpack(self, data: bytearray):
    archive = GzipHeader(data)
    path = archive.name
    date = archive.mtime
    date = date and datetime.fromtimestamp(date) or None
    if path is None:
        try:
            meta = metavars(data)
            path = Path(meta['path'])
        except KeyError:
            path = 'ungz'
        else:
            self.log_warn(path)
            suffix = path.suffix
            if suffix.lower() == '.gz':
                path = path.with_suffix('')
            else:
                path = path.with_suffix(F'{suffix}.ungz')
            path = path.as_posix()
    yield self._pack(path, date, archive.data)

Inherited members