+ """Close and (if io_db["kicked_by_rival"] false) remove files in io_db."""
+ def helper(file_key, path_key):
+ if file_key in io_db:
+ io_db[file_key].close()
+ if not io_db["kicked_by_rival"] \
+ and os.access(io_db[path_key], os.F_OK):
+ os.remove(io_db[path_key])
+ helper("file_out", "path_out")
+ helper("file_in", "path_in")
+ helper("file_worldstate", "path_worldstate")
+
+
+def detect_atomic_leftover(path, tmp_suffix):
+ """Raise explained SystemExit if file is found at path + tmp_suffix."""
+ path_tmp = path + tmp_suffix
+ msg = "Found file '" + path_tmp + "' that may be a leftover from an " \
+ "aborted previous attempt to write '" + path + "'. Aborting until " \
+ "the matter is resolved by removing it from its current path."
+ if os.access(path_tmp, os.F_OK):
+ raise SystemExit(msg)
+
+
+def obey(cmd, io_db, prefix, replay_file=None, do_record=False):
+ """"""
+ server_test(io_db)
+ print("input " + prefix + ": " + cmd)
+ try:
+ tokens = shlex.split(cmd, comments=True)
+ except ValueError as err:
+ print("Can't tokenize command string: " + str(err) + ".")
+ return
+ if 0 == len(tokens):
+ pass
+ elif "PING" == tokens[0] and 1 == len(tokens):
+ io_db["file_out"].write("PONG\n")
+ io_db["file_out"].flush()
+ elif "QUIT" == tokens[0] and 1 == len(tokens):
+ if do_record:
+ record("# " + cmd, io_db)
+ raise SystemExit("received QUIT command")
+ elif "MAKE_WORLD" == tokens[0] and 2 == len(tokens):
+ if replay_file:
+ print("Due to replay mode, reading command as 'go on in record'.")
+ line = replay_file.readline()
+ if len(line) > 0:
+ obey(line.rstrip(), io_db,
+ replay_file.prefix + str(file.line_n))
+ file.line_n = file.line_n + 1
+ else:
+ print("Reached end of record file.")
+ else:
+ print("I would generate a new world now, if only I knew how.")
+ if do_record:
+ record(cmd, io_db)
+ else:
+ print("Invalid command/argument, or bad number of tokens.")
+
+
+def record(cmd, io_db):
+ """Append cmd string plus newline to file at path_recordfile. (Atomic.)"""
+ # This misses some optimizations from the original record(), namely only
+ # finishing the atomic write with expensive flush() and fsync() every 15
+ # seconds unless explicitely forced. Implement as needed.
+ path_tmp = io_db["path_record"] + io_db["tmp_suffix"]
+ if os.access(io_db["path_record"], os.F_OK):
+ shutil.copyfile(io_db["path_record"], path_tmp)
+ file = open(path_tmp, "a")
+ file.write(cmd + "\n")
+ file.flush()
+ os.fsync(file.fileno())
+ file.close()
+ if os.access(io_db["path_record"], os.F_OK):
+ os.remove(io_db["path_record"])
+ os.rename(path_tmp, io_db["path_record"])
+
+
+def obey_lines_in_file(path, name, do_record=False):
+ """Call obey() on each line of path's file, use name in input prefix."""
+ file = open(path, "r")
+ line_n = 1
+ for line in file.readlines():
+ obey(line.rstrip(), io_db, name + "file line " + str(line_n),
+ do_record=do_record)
+ line_n = line_n + 1
+ file.close()
+
+
+def parse_command_line_arguments():
+ """Return settings values read from command line arguments."""
+ parser = argparse.ArgumentParser()
+ parser.add_argument('-s', nargs='?', type=int, dest='replay', const=1,
+ action='store')
+ opts, unknown = parser.parse_known_args()
+ return opts
+
+
+def server_test(io_db):
+ """Ensure valid server out file belonging to current process.
+
+ On failure, set io_db["kicked_by_rival"] and raise SystemExit.
+ """
+ if not os.access(io_db["path_out"], os.F_OK):
+ raise SystemExit("Server output file has disappeared.")
+ file = open(io_db["path_out"], "r")
+ test = file.readline().rstrip("\n")
+ file.close()
+ if test != io_db["teststring"]:
+ io_db["kicked_by_rival"] = True
+ msg = "Server test string in server output file does not match. This" \
+ " indicates that the current server process has been " \
+ "superseded by another one."
+ raise SystemExit(msg)
+
+
+def read_command(io_db):
+ """Return next newline-delimited command from server in file.
+
+ Keep building return string until a newline is encountered. Pause between
+ unsuccessful reads, and after too much waiting, run server_test().
+ """
+ wait_on_fail = 1
+ max_wait = 5
+ now = time.time()
+ command = ""
+ while 1:
+ add = io_db["file_in"].readline()
+ if len(add) > 0:
+ command = command + add
+ if len(command) > 0 and "\n" == command[-1]:
+ command = command[:-1]
+ break
+ else:
+ time.sleep(wait_on_fail)
+ if now + max_wait < time.time():
+ server_test(io_db)
+ now = time.time()
+ return command
+