| 1 | """Management for daemon processes |
| 2 | |
| 3 | This module contains a utility to listen for management commands on a |
| 4 | socket, lending itself to managing daemon processes. |
| 5 | """ |
| 6 | |
| 7 | import os, sys, socket, threading, grp, select |
| 8 | import types, pprint, traceback |
| 9 | |
| 10 | class repl(object): |
| 11 | def __init__(self, cl): |
| 12 | self.cl = cl |
| 13 | self.mod = types.ModuleType("repl") |
| 14 | self.mod.echo = self.echo |
| 15 | self.printer = pprint.PrettyPrinter(indent = 4, depth = 6) |
| 16 | cl.sk.send("+REPL\n") |
| 17 | |
| 18 | def echo(self, ob): |
| 19 | self.cl.sk.send(self.printer.pformat(ob) + "\n") |
| 20 | |
| 21 | def command(self, cmd): |
| 22 | try: |
| 23 | try: |
| 24 | ccode = compile(cmd, "PDM Input", "eval") |
| 25 | except SyntaxError: |
| 26 | ccode = compile(cmd, "PDM Input", "exec") |
| 27 | exec ccode in self.mod.__dict__ |
| 28 | self.cl.sk.send("+OK\n") |
| 29 | else: |
| 30 | self.echo(eval(ccode, self.mod.__dict__)) |
| 31 | self.cl.sk.send("+OK\n") |
| 32 | except: |
| 33 | for line in traceback.format_exception(*sys.exc_info()): |
| 34 | self.cl.sk.send(line) |
| 35 | self.cl.sk.send("+EXC\n") |
| 36 | |
| 37 | def handle(self, buf): |
| 38 | p = buf.find("\n\n") |
| 39 | if p < 0: |
| 40 | return buf |
| 41 | cmd = buf[:p + 1] |
| 42 | self.command(cmd) |
| 43 | return buf[p + 2:] |
| 44 | |
| 45 | class client(threading.Thread): |
| 46 | def __init__(self, sk): |
| 47 | super(client, self).__init__(name = "Management client") |
| 48 | self.setDaemon(True) |
| 49 | self.sk = sk |
| 50 | self.handler = self |
| 51 | |
| 52 | def choose(self, proto): |
| 53 | if proto == "repl": |
| 54 | self.handler = repl(self) |
| 55 | else: |
| 56 | self.sk.send("-ERR Unknown protocol: %s\n" % proto) |
| 57 | raise Exception() |
| 58 | |
| 59 | def handle(self, buf): |
| 60 | p = buf.find("\n") |
| 61 | if p >= 0: |
| 62 | proto = buf[:p] |
| 63 | buf = buf[p + 1:] |
| 64 | self.choose(proto) |
| 65 | return buf |
| 66 | |
| 67 | def run(self): |
| 68 | try: |
| 69 | buf = "" |
| 70 | self.sk.send("+PDM1\n") |
| 71 | while True: |
| 72 | ret = self.sk.recv(1024) |
| 73 | if ret == "": |
| 74 | return |
| 75 | buf += ret |
| 76 | while True: |
| 77 | try: |
| 78 | nbuf = self.handler.handle(buf) |
| 79 | except: |
| 80 | return |
| 81 | if nbuf == buf: |
| 82 | break |
| 83 | buf = nbuf |
| 84 | finally: |
| 85 | self.sk.close() |
| 86 | |
| 87 | class listener(threading.Thread): |
| 88 | def __init__(self): |
| 89 | super(listener, self).__init__(name = "Management listener") |
| 90 | self.setDaemon(True) |
| 91 | |
| 92 | def listen(self, sk): |
| 93 | self.running = True |
| 94 | while self.running: |
| 95 | rfd, wfd, efd = select.select([sk], [], [sk], 1) |
| 96 | for fd in rfd: |
| 97 | if fd == sk: |
| 98 | nsk, addr = sk.accept() |
| 99 | self.accept(nsk, addr) |
| 100 | |
| 101 | def stop(self): |
| 102 | self.running = False |
| 103 | self.join() |
| 104 | |
| 105 | def accept(self, sk, addr): |
| 106 | cl = client(sk) |
| 107 | cl.start() |
| 108 | |
| 109 | class unixlistener(listener): |
| 110 | def __init__(self, name, mode = 0600, group = None): |
| 111 | super(unixlistener, self).__init__() |
| 112 | self.name = name |
| 113 | self.mode = mode |
| 114 | self.group = group |
| 115 | |
| 116 | def run(self): |
| 117 | sk = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) |
| 118 | ul = False |
| 119 | try: |
| 120 | if os.path.exists(self.name) and os.path.stat.S_ISSOCK(os.stat(self.name).st_mode): |
| 121 | os.unlink(self.name) |
| 122 | sk.bind(self.name) |
| 123 | ul = True |
| 124 | os.chmod(self.name, self.mode) |
| 125 | if self.group is not None: |
| 126 | os.chown(self.name, os.getuid(), grp.getgrnam(self.group).gr_gid) |
| 127 | sk.listen(16) |
| 128 | self.listen(sk) |
| 129 | finally: |
| 130 | sk.close() |
| 131 | if ul: |
| 132 | os.unlink(self.name) |
| 133 | |
| 134 | class tcplistener(listener): |
| 135 | def __init__(self, port, bindaddr = "127.0.0.1"): |
| 136 | super(tcplistener, self).__init__() |
| 137 | self.port = port |
| 138 | self.bindaddr = bindaddr |
| 139 | |
| 140 | def run(self): |
| 141 | sk = socket.socket(socket.AF_INET, socket.SOCK_STREAM) |
| 142 | try: |
| 143 | sk.bind((self.bindaddr, self.port)) |
| 144 | sk.listen(16) |
| 145 | self.listen(sk) |
| 146 | finally: |
| 147 | sk.close() |