X-Git-Url: https://git.ralfj.de/saartuer.git/blobdiff_plain/01b0198699d9871bf642930ece770d0d1be917b9..07282bc03a4f1dfcd9309f2fa242dfecb2756a3b:/tuerd diff --git a/tuerd b/tuerd index a283f26..f03d5db 100755 --- a/tuerd +++ b/tuerd @@ -1,15 +1,21 @@ #!/usr/bin/python3 -import time, socket, os, stat +import time, socket, os, stat, atexit, errno, struct, pwd +from libtuer import log from datetime import datetime import RPi.GPIO as GPIO +SO_PEERCRED = 17 # DO - NOT - TOUCH GPIO.setmode(GPIO.BOARD) +atexit.register(GPIO.cleanup) -# ******** definitions ********* -# logging function -# TODO: loglevel, log like a real daemon -def log (what): - print (datetime.now(),what) +#tmp +def recv_timeout(conn, size, time): + (r, w, x) = select.select([conn], [], [], time) + if len(r): + assert r[0] == conn + return conn.recv(size) + return None +# ******** definitions ********* # send to client for information but don't care if it arrives def waynesend (conn, what): try: @@ -23,6 +29,15 @@ def doNothing (conn): waynesend(conn,b"0") pass +# delete a file, don't care if it did not exist in the first place +def forcerm(name): + try: + os.unlink (name) + except OSError as e: + # only ignore error if it was "file didn't exist" + if e.errno != errno.ENOENT: + raise + # commands: on a pin do a series of timed on/off switches class Pinoutput: # name is for logging and also used for mapping command names to instances of this class @@ -37,9 +52,10 @@ class Pinoutput: def __call__ (self, conn): for (value,delay) in self.todo: GPIO.output(self.pin, value) - log ("%s: Pin %d set to %s." % (self.name,self.pin,str(value))) + # log ("%s: Pin %d set to %s." % (self.name,self.pin,str(value))) time.sleep(delay) # notify success + log waynesend(conn,b"1") # ******** configuration ********* @@ -60,10 +76,7 @@ for pin in pinlist: # create socket sock = socket.socket (socket.AF_UNIX, socket.SOCK_STREAM) # delete old socket file and don't bitch around if it's not there -try: - os.unlink (socketname) -except OSError: - pass +forcerm(socketname) # bind socket to file name sock.bind (socketname) # allow only users in the tuergroup to write to the socket @@ -72,22 +85,31 @@ os.chmod (socketname, stat.S_IRUSR | stat.S_IWUSR | stat.S_IRGRP | stat.S_IWGRP) # listen to the people, but not too many at once sock.listen(1) +# shutdown handling +def shutdown(): + log("Shutting down") + sock.close() + forcerm(socketname) +atexit.register(shutdown) + # main loop # FIXME: DoS by opening socket but not sending data, because this loop is single threaded; maybe settimeout helps a bit. while True: # accept connections conn, addr = sock.accept() - # TODO: use addr to determine the client for logging - # get some data from the client (enough to hold any valid command) - data = conn.recv (32) - # log the command - log("received command: %s" % str(data)) - # lookup the command, if it's not in the dict, use the doNothing function instead - # and execute the looked up command or doNothing with the connection, so it can respond to the client - pindict.get(data,doNothing)(conn) - # close connection cleanly - conn.close() - -# FIXME will this be executed after receiving a terminating signal? -GPIO.cleanup() + try: + # get peer information + (pid, uid, gid) = (struct.unpack('3i', conn.getsockopt(socket.SOL_SOCKET, SO_PEERCRED, struct.calcsize('3i')))) + # get some data from the client (enough to hold any valid command) + data = conn.recv (32) + # log the command + log("received command from %s (uid %d): %s" % (pwd.getpwuid(uid).pw_name,uid, str(data))) + # lookup the command, if it's not in the dict, use the doNothing function instead + # and execute the looked up command or doNothing with the connection, so it can respond to the client + pindict.get(data,doNothing)(conn) + log("done") + # close connection cleanly + conn.close() + except Exception as e: + log("Something went wrong: %s\n...continuing." % str(e))