platform/platform-resources/src/launcher.py

#!/usr/bin/python

import socket
import struct
import sys
import os
import time

# see com.intellij.idea.SocketLock for the server side of this interface

RUN_PATH = '$RUN_PATH$'
CONFIG_PATH = '$CONFIG_PATH$'

args = []
skip_next = False
for i, arg in enumerate(sys.argv[1:]):
    if arg == '-h' or arg == '-?' or arg == '--help':
        print(('Usage:\n' + \
               '  {0} -h |-? | --help\n' + \
               '  {0} [-l|--line line] file[:line]\n' + \
               '  {0} diff <left> <right>' + \
               '  {0} merge <local> <remote> [base] <merged>').format(sys.argv[0]))
        exit(0)
    elif ':' in arg:
        file_path, line_number = arg.rsplit(':', 1)
        if line_number.isdigit():
          args.append('-l')
          args.append(line_number)
          args.append(file_path)
        else:
          args.append(arg)
    else:
        args.append(arg)

def launch_with_port(port):
    found = False

    s = socket.socket()
    s.settimeout(0.3)
    try:
        s.connect(('127.0.0.1', port))
    except:
        return False

    while True:
        try:
            path_len = struct.unpack(">h", s.recv(2))[0]
            path = s.recv(path_len)
            if os.path.abspath(path) == os.path.abspath(CONFIG_PATH):
                found = True
                break
        except:
            break

    if found:
        if args:
            cmd = "activate " + os.getcwd() + "\0" + "\0".join(args)
            encoded = struct.pack(">h", len(cmd)) + cmd
            s.send(encoded)
            time.sleep(0.5)   # don't close socket immediately
        return True

    return False

port = -1
try:
    f = open(os.path.join(CONFIG_PATH, 'port'))
    port = int(f.read())
except Exception:
    type, value, traceback = sys.exc_info()
    print(value)
    port = -1

if port == -1:
    # SocketLock actually allows up to 50 ports, but the checking takes too long
    for port in range(6942, 6942+10):
        if launch_with_port(port): exit()
else:
    if launch_with_port(port): exit()

bin_dir, bin_file = os.path.split(RUN_PATH)
os.execv(RUN_PATH, [bin_file] + args)