#! /usr/bin/python3
# -*- python -*-
# -*- coding: utf-8 -*-


import socket
import _thread


fn = '/home/pc/soft/OS/ubuntu-18.04.1-desktop-amd64.iso'
lock = _thread.allocate_lock()


def printl(s):
    lock.acquire()
    print(s)
    lock.release()


def dl(client_socket, addr):
    try:
        printl(f'sending file to {addr}')
        with open(fn, 'rb') as f:
            while True:
                #printl(CHUNK_SIZE) тут оно пишет правильную цифру и вообще все работает как задумано
                data = f.read(CHUNK_SIZE)
                if not data: break
                client_socket.send(data)
        printl(f'complete to {addr}')
    except ConnectionResetError:
        printl(f'aborted to {addr}')
    client_socket.close()


if __name__ == '__main__':
    CHUNK_SIZE = 128 * 1024
    server_socket = socket.socket()
    server_socket.bind(('', 12345))
    server_socket.listen(5)
    while True:
        client_socket, addr = server_socket.accept()
        _thread.start_new_thread(dl, (client_socket, addr))
    server_socket.close()