Files
kitty/kitty/child.py
2016-12-06 11:26:01 +05:30

84 lines
2.5 KiB
Python

#!/usr/bin/env python
# vim:fileencoding=utf-8
# License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
import os
import termios
import struct
import fcntl
import signal
from .constants import terminfo_dir
class Child:
child_fd = pid = None
forked = False
def __init__(self, argv, cwd, opts):
self.argv = argv
self.cwd = os.path.abspath(os.path.expandvars(os.path.expanduser(cwd or os.getcwd())))
self.opts = opts
def fork(self):
if self.forked:
return
self.forked = True
master, slave = os.openpty()
fcntl.fcntl(slave, fcntl.F_SETFD, fcntl.fcntl(slave, fcntl.F_GETFD) & ~fcntl.FD_CLOEXEC)
# Note that master and slave are in blocking mode
pid = os.fork()
if pid == 0: # child
try:
os.chdir(self.cwd)
except EnvironmentError:
os.chdir('/')
os.setsid()
for i in range(3):
os.dup2(slave, i)
os.close(slave), os.close(master)
os.closerange(3, 200)
# Establish the controlling terminal (see man 7 credentials)
os.close(os.open(os.ttyname(1), os.O_RDWR))
os.environ['TERM'] = self.opts.term
os.environ['COLORTERM'] = 'truecolor'
if os.path.isdir(terminfo_dir):
os.environ['TERMINFO'] = terminfo_dir
try:
os.execvp(self.argv[0], self.argv)
except Exception as err:
print('Could not launch:', self.argv[0])
print('\t', err)
input('\nPress Enter to exit:')
else: # master
os.close(slave)
self.pid = pid
self.child_fd = master
return pid
def resize_pty(self, w, h):
if self.child_fd is not None:
fcntl.ioctl(self.child_fd, termios.TIOCSWINSZ, struct.pack('4H', h, w, 0, 0))
def hangup(self):
if self.pid is not None:
pid, self.pid = self.pid, None
try:
pgrp = os.getpgid(pid)
except ProcessLookupError:
return
os.killpg(pgrp, signal.SIGHUP)
os.close(self.child_fd)
self.child_fd = None
def __del__(self):
self.hangup()
def get_child_status(self):
if self.pid is not None:
try:
return os.waitid(os.P_PID, self.pid, os.WEXITED | os.WNOHANG)
except ChildProcessError:
self.pid = None