+import argparse
import errno
import os
+import shlex
+import shutil
import time
-class HandledException(Exception):
- """Feature-less Exception child. Use for expected operational errors."""
-
- pass
-
-
-def setup_server_io(io_db):
+def setup_server_io():
"""Fill IO files DB with proper file( path)s. Write process IO test string.
- Ensure IO files directory at server/. Remove any old in file if found. Set
- up new in file (io_db["file_in"]) for reading at io_db["path_in"], and new
- out file (io_db["file_out"]) for writing at io_db["path_out"]. Start out
- file with process hash line of format PID + " " + floated UNIX time
- (io_db["teststring"]). Set worldstate file path io_db["path_worldstate"].
+ Set io_db["kicked_by_rival"] to False. Decide file paths. Ensure IO files
+ directory at server/. Remove any old in file if found. Set up new in file
+ (io_db["file_in"]) for reading at io_db["path_in"], and new out file
+ (io_db["file_out"]) for writing at io_db["path_out"]. Start out file with
+ process hash line of format PID + " " + floated UNIX time
+ (io_db["teststring"]). Run detect_atomic_leftover on io_db["path_record"]
+ and io_db["path_save"].
"""
io_dir = "server/"
+ io_db["kicked_by_rival"] = False
io_db["path_in"] = io_dir + "in"
io_db["path_out"] = io_dir + "out"
io_db["path_worldstate"] = io_dir + "worldstate"
+ io_db["path_record"] = "record"
+ io_db["path_save"] = "save"
+ io_db["path_worldconf"] = "confserver/world"
+ io_db["tmp_suffix"] = "_tmp"
io_db["teststring"] = str(os.getpid()) + " " + str(time.time())
os.makedirs(io_dir, exist_ok=True)
io_db["file_out"] = open(io_db["path_out"], "w")
io_db["file_out"].write(io_db["teststring"] + "\n")
+ io_db["file_out"].flush()
if os.access(io_db["path_in"], os.F_OK):
os.remove(io_db["path_in"])
io_db["file_in"] = open(io_db["path_in"], "w")
io_db["file_in"].close()
io_db["file_in"] = open(io_db["path_in"], "r")
+ detect_atomic_leftover(io_db["path_save"], io_db["tmp_suffix"])
+ detect_atomic_leftover(io_db["path_record"], io_db["tmp_suffix"])
-def cleanup_server_io(io_db):
- """Close and remove all files in IO files DB."""
- io_db["file_out"].close()
- os.remove(io_db["path_out"])
- io_db["file_in"].close()
- os.remove(io_db["path_in"])
- if "file_worldstate" in io_db: # This file's only set up
- io_db["file_worldstate"].close() # properly when the game
- if os.access(io_db["path_worldstate"], os.F_OK): # world is active, which
- os.remove(io_db["path_worldstate"]) # is not guaranteed.
+def cleanup_server_io():
+ """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")
+ if "file_record" in io_db:
+ io_db["file_record"].close()
-def detect_atomic_leftover(path):
- """Raise explained HandledException if file is found at path + "_tmp"."""
- path_tmp = path + "_tmp"
+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 HandledException(msg)
+ raise SystemExit(msg)
+
+
+def obey(command, prefix, replay=False, do_record=False):
+ """Call function from commands_db mapped to command's first token.
+
+ The command string is tokenized by shlex.split(comments=True). If replay is
+ set, a non-meta command from the commands_db merely triggers obey() on the
+ next command from the records file. Non-meta commands are recorded in
+ non-replay mode if do_record is set. The prefix string is inserted into the
+ server's input message between its beginning 'input ' and ':'. All activity
+ is preceded by a call to server_test().
+ """
+ server_test()
+ print("input " + prefix + ": " + command)
+ try:
+ tokens = shlex.split(command, comments=True)
+ except ValueError as err:
+ print("Can't tokenize command string: " + str(err) + ".")
+ return
+ if len(tokens) > 0 and tokens[0] in commands \
+ and len(tokens) >= commands[tokens[0]][0] + 1:
+ if commands[tokens[0]][1]:
+ commands[tokens[0]][2]()
+ elif replay:
+ print("Due to replay mode, reading command as 'go on in record'.")
+ line = io_db["file_record"].readline()
+ if len(line) > 0:
+ obey(line.rstrip(), io_db["file_record"].prefix
+ + str(io_db["file_record"].line_n))
+ io_db["file_record"].line_n = io_db["file_record"].line_n + 1
+ else:
+ print("Reached end of record file.")
+ else:
+ commands[tokens[0]][2]()
+ if do_record:
+ record(command)
+ else:
+ print("Invalid command/argument, or bad number of tokens.")
+
+
+def record(command):
+ """Append command string plus newline to record file. (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(command + "\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(), 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():
+ """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():
+ """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()
+ now = time.time()
+ return command
+
+
+def command_makeworld():
+ """Mere dummy so far."""
+ print("I would build a whole world now if only I knew how.")
+
+
+def command_ping():
+ """Send PONG line to server output file."""
+ io_db["file_out"].write("PONG\n")
+ io_db["file_out"].flush()
+
+
+def command_quit():
+ """Abort server process."""
+ raise SystemExit("received QUIT command")
+
+
+"""Commands database.
+Map command start tokens to ([0]) minimum number of expected command arguments,
+([1]) the command's meta-ness (i.e. is it to be written to the record file, is
+it to be ignored in replay mode if read from server input file), and ([2]) a
+function to be called on it.
+"""
+commands_db = {
+ "QUIT": (0, True, command_quit),
+ "PING": (0, True, command_ping),
+ "MAKE_WORLD": (1, False, command_makeworld)
+}
io_db = {}
+world_db = {}
try:
- print("DUMMY: Obey command-line arguments.")
- print("DUMMY: Open files.")
- setup_server_io(io_db)
- print("DUMMY: Run game.")
- path_recordfile = "recordfile"
- path_savefile = "savefile"
- detect_atomic_leftover(path_savefile)
- detect_atomic_leftover(path_recordfile)
- if os.access(path_savefile, os.F_OK):
- print(open(path_savefile, "r").read())
+ opts = parse_command_line_arguments()
+ setup_server_io()
+ # print("DUMMY: Run game.")
+ if None != opts.replay:
+ if opts.replay < 1:
+ opts.replay = 1
+ print("Replay mode. Auto-replaying up to turn " + str(opts.replay) +
+ " (if so late a turn is to be found).")
+ if not os.access(io_db["path_record"], os.F_OK):
+ raise SystemExit("No record file found to replay.")
+ world_db["turn"] = 0
+ io_db["file_record"] = open(io_db["path_record"], "r")
+ io_db["file_record"].prefix = "recod file line "
+ io_db["file_record"].line_n = 1
+ while world_db["turn"] < opts.replay:
+ line = io_db["file_record"].readline()
+ if "" == line:
+ break
+ obey(line.rstrip(), io_db["file_record"].prefix
+ + str(io_db["file_record"].line_n))
+ io_db["file_record"].line_n = io_db["file_record"].line_n + 1
+ while True:
+ obey(read_command(), "in file", replay=True)
else:
- msg = "MAKE_WORLD " + str(int(time.time()))
- print(msg)
-except HandledException as exception:
- print("Error:")
- print(exception.args[0])
+ if os.access(io_db["path_save"], os.F_OK):
+ obey_lines_in_file(io_db["path_save"], "save")
+ else:
+ if not os.access(io_db["path_worldconf"], os.F_OK):
+ msg = "No world config file from which to start a new world."
+ raise SystemExit(msg)
+ obey_lines_in_file(io_db["path_worldconf"], "world config ",
+ do_record=True)
+ obey("MAKE_WORLD " + str(int(time.time())), "in file",
+ do_record=True)
+ while True:
+ obey(read_command(), "in file", do_record=True)
+except SystemExit as exit:
+ print("ABORTING: " + exit.args[0])
except:
print("SOMETHING WENT WRONG IN UNEXPECTED WAYS")
raise
finally:
- cleanup_server_io(io_db)
- print("DUMMY: (Clean up C heap.)")
+ cleanup_server_io()
+ # print("DUMMY: (Clean up C heap.)")
projects / plomrogue / blobdiff