Files
mc_ulzx/ulzx
2023-10-23 18:16:22 +02:00

139 lines
4.3 KiB
Python
Executable File

#!/usr/bin/env python3
"""
Read only, Amiga LZX[1] archiver Virtual filesystem executive for Midnight
Commander.
Tested against python 3.8, unlzx[1] 1.1 and mc 4.8.22
[1] ftp://us.aminet.net/pub/aminet/misc/unix/unlzx.c.gz.readme
Changelog:
1.3 Code cleanup
1.2 Use python3
1.1 Moved common code into extfslib library
1.0 Initial release
Author: Roman 'gryf' Dobosz <gryf73@gmail.com>
Date: 2023-10-20
Version: 1.3
Licence: BSD
"""
import os
import re
import shutil
import subprocess
import sys
import tempfile
import extfslib
class ULzx(extfslib.Archive):
"""LZX archive handle. Provides interface to MC's extfs subsystem"""
LINE_PAT = re.compile(r"^\s+(?P<size>\d+)\s+"
r"((n/a)|\d+)\s"
r"(?P<time>\d{2}:\d{2}:\d{2})\s+"
r"(?P<date>\d+-[a-z]{3}-\d{4})\s"
r"(?P<perms>[h-][s-][p-][a-][r-][w-][e-][d-])\s"
r"\"(?P<fpath>.*)\"")
ARCHIVER = "unlzx"
CMDS = {"list": "-v",
"read": "-x"}
DATETIME = "%02d-%02d-%s %02d:%02d"
def _get_date(self, time, date):
"""Return MM-DD-YYYY hh:mm formatted date out of time and date
strings"""
month_list = ["jan", "fe", "mar", "apr", "may", "jun", "jul",
"aug", "sep", "oct", "nov", "dec"]
day, month, year = date.split("-")
month = month_list.index(month) + 1
hours, minutes, dummy = time.split(":")
return self.DATETIME % (month, int(day), year, int(hours),
int(minutes))
def _get_dir(self):
"""Prepare archive file listing"""
contents = []
out = subprocess.run([self.ARCHIVER, self.CMDS['list'], self._arch],
capture_output=True, encoding="latin-1")
if out.stderr:
sys.stderr.write(out.stderr)
for line in out.stdout.split("\n"):
match = self.LINE_PAT.match(line)
if not match:
continue
match_entry = match.groupdict()
entry = {}
for key in match_entry:
entry[key] = match_entry[key]
del match_entry
entry['datetime'] = self._get_date(entry['time'], entry['date'])
entry['display_name'] = self._map_name(entry['fpath'])
entry['perms'] = "-rw-r--r--" # lzx doesn't store empty dirs
entry['uid'] = str(self._uid)
entry['gid'] = str(self._gid)
contents.append(entry)
return contents
def list(self):
"""Output contents of the archive to stdout"""
for entry in self._contents:
sys.stdout.write(self.ITEM.decode('utf-8') % entry)
return 0
def run(self, dst):
"""Execute file out of archive"""
fdesc, tmp_file = tempfile.mkstemp()
os.close(fdesc)
result = 0
if self.copyout(dst, tmp_file) != 0:
result = 1
os.chmod(tmp_file, int("700", 8))
with open(os.devnull, "w") as fnull:
result = subprocess.run([tmp_file], stderr=fnull)
os.unlink(tmp_file)
return result.returncode
def copyout(self, src, dst):
"""Unfortunately, to copy one file out entire LZX archive have to be
extracted. For small archives is not a problem, but in relatively big
one it could be a performance issue."""
tmp_dir = tempfile.mkdtemp()
src = [e['display_name'] for e in self._contents
if e['display_name'] == src]
if not src:
raise IOError("No such file or directory")
src = src[0].encode('latin-1')
current_dir = os.path.abspath(os.curdir)
os.chdir(tmp_dir)
with open(os.devnull, "w") as fnull:
result = subprocess.run([self.ARCHIVER, self.CMDS['read'],
os.path.join(current_dir, self._arch)],
stdout=fnull, stderr=fnull)
if result.returncode == 0:
# use subprocess, as shutil.copy2 will complain about mixing
# strings with bytes
subprocess.run(['cp', src, dst])
shutil.rmtree(tmp_dir)
os.chdir(current_dir)
return result.returncode
if __name__ == "__main__":
sys.exit(extfslib.parse_args(ULzx))