| 1 | import sys, os, errno, threading, select, traceback |
| 2 | |
| 3 | class epoller(object): |
| 4 | exc_handler = None |
| 5 | |
| 6 | def __init__(self, check=None): |
| 7 | self.registered = {} |
| 8 | self.lock = threading.RLock() |
| 9 | self.ep = None |
| 10 | self.th = None |
| 11 | self.stopped = False |
| 12 | self.loopcheck = set() |
| 13 | if check is not None: |
| 14 | self.loopcheck.add(check) |
| 15 | self._daemon = True |
| 16 | |
| 17 | @staticmethod |
| 18 | def _evsfor(ch): |
| 19 | return ((select.EPOLLIN if ch.readable else 0) | |
| 20 | (select.EPOLLOUT if ch.writable else 0)) |
| 21 | |
| 22 | def _ckrun(self): |
| 23 | if self.registered and self.th is None: |
| 24 | th = threading.Thread(target=self._run, name="Async epoll thread") |
| 25 | th.daemon = self._daemon |
| 26 | th.start() |
| 27 | self.th = th |
| 28 | |
| 29 | def exception(self, ch, *exc): |
| 30 | self.remove(ch) |
| 31 | if self.exc_handler is None: |
| 32 | traceback.print_exception(*exc) |
| 33 | else: |
| 34 | self.exc_handler(ch, *exc) |
| 35 | |
| 36 | def _cb(self, ch, nm): |
| 37 | try: |
| 38 | m = getattr(ch, nm, None) |
| 39 | if m is None: |
| 40 | raise AttributeError("%r has no %s method" % (ch, nm)) |
| 41 | m() |
| 42 | except Exception as exc: |
| 43 | self.exception(ch, *sys.exc_info()) |
| 44 | |
| 45 | def _closeall(self): |
| 46 | with self.lock: |
| 47 | while self.registered: |
| 48 | fd, (ch, evs) = next(iter(self.registered.items())) |
| 49 | del self.registered[fd] |
| 50 | self.ep.unregister(fd) |
| 51 | self._cb(ch, "close") |
| 52 | |
| 53 | def _run(self): |
| 54 | ep = select.epoll() |
| 55 | try: |
| 56 | with self.lock: |
| 57 | try: |
| 58 | for fd, (ob, evs) in self.registered.items(): |
| 59 | ep.register(fd, evs) |
| 60 | except: |
| 61 | self.registered.clear() |
| 62 | raise |
| 63 | self.ep = ep |
| 64 | |
| 65 | while self.registered: |
| 66 | for ck in self.loopcheck: |
| 67 | ck(self) |
| 68 | if self.stopped: |
| 69 | self._closeall() |
| 70 | break |
| 71 | try: |
| 72 | evlist = ep.poll(10) |
| 73 | except IOError as exc: |
| 74 | if exc.errno == errno.EINTR: |
| 75 | continue |
| 76 | raise |
| 77 | for fd, evs in evlist: |
| 78 | with self.lock: |
| 79 | if fd not in self.registered: |
| 80 | continue |
| 81 | ch, cevs = self.registered[fd] |
| 82 | if fd in self.registered and evs & (select.EPOLLIN | select.EPOLLHUP | select.EPOLLERR): |
| 83 | self._cb(ch, "read") |
| 84 | if fd in self.registered and evs & select.EPOLLOUT: |
| 85 | self._cb(ch, "write") |
| 86 | if fd in self.registered: |
| 87 | nevs = self._evsfor(ch) |
| 88 | if nevs == 0: |
| 89 | del self.registered[fd] |
| 90 | ep.unregister(fd) |
| 91 | self._cb(ch, "close") |
| 92 | elif nevs != cevs: |
| 93 | self.registered[fd] = ch, nevs |
| 94 | ep.modify(fd, nevs) |
| 95 | |
| 96 | finally: |
| 97 | with self.lock: |
| 98 | self.th = None |
| 99 | self.ep = None |
| 100 | self._ckrun() |
| 101 | ep.close() |
| 102 | |
| 103 | @property |
| 104 | def daemon(self): return self._daemon |
| 105 | @daemon.setter |
| 106 | def daemon(self, value): |
| 107 | self._daemon = bool(value) |
| 108 | with self.lock: |
| 109 | if self.th is not None: |
| 110 | self.th = daemon = self._daemon |
| 111 | |
| 112 | def add(self, ch): |
| 113 | with self.lock: |
| 114 | fd = ch.fileno() |
| 115 | if fd in self.registered: |
| 116 | raise KeyError("fd %i is already registered" % fd) |
| 117 | evs = self._evsfor(ch) |
| 118 | if evs == 0: |
| 119 | ch.close() |
| 120 | return |
| 121 | ch.watcher = self |
| 122 | self.registered[fd] = (ch, evs) |
| 123 | if self.ep: |
| 124 | self.ep.register(fd, evs) |
| 125 | self._ckrun() |
| 126 | |
| 127 | def remove(self, ch, ignore=False): |
| 128 | with self.lock: |
| 129 | fd = ch.fileno() |
| 130 | if fd not in self.registered: |
| 131 | if ignore: |
| 132 | return |
| 133 | raise KeyError("fd %i is not registered" % fd) |
| 134 | pch, cevs = self.registered[fd] |
| 135 | if pch is not ch: |
| 136 | raise ValueError("fd %i registered via object %r, cannot remove with %r" % (pch, ch)) |
| 137 | del self.registered[fd] |
| 138 | if self.ep: |
| 139 | self.ep.unregister(fd) |
| 140 | ch.close() |
| 141 | |
| 142 | def update(self, ch, ignore=False): |
| 143 | with self.lock: |
| 144 | fd = ch.fileno() |
| 145 | if fd not in self.registered: |
| 146 | if ignore: |
| 147 | return |
| 148 | raise KeyError("fd %i is not registered" % fd) |
| 149 | pch, cevs = self.registered[fd] |
| 150 | if pch is not ch: |
| 151 | raise ValueError("fd %i registered via object %r, cannot update with %r" % (pch, ch)) |
| 152 | evs = self._evsfor(ch) |
| 153 | if evs == 0: |
| 154 | del self.registered[fd] |
| 155 | if self.ep: |
| 156 | self.ep.unregister(fd) |
| 157 | ch.close() |
| 158 | elif evs != cevs: |
| 159 | self.registered[fd] = ch, evs |
| 160 | if self.ep: |
| 161 | self.ep.modify(fd, evs) |
| 162 | |
| 163 | def stop(self): |
| 164 | if threading.current_thread() == self.th: |
| 165 | self.stopped = True |
| 166 | else: |
| 167 | def tgt(): |
| 168 | self.stopped = True |
| 169 | cb = callbuffer() |
| 170 | cb.call(tgt) |
| 171 | cb.stop() |
| 172 | self.add(cb) |
| 173 | |
| 174 | def watcher(): |
| 175 | return epoller() |
| 176 | |
| 177 | class channel(object): |
| 178 | readable = False |
| 179 | writable = False |
| 180 | |
| 181 | def __init__(self): |
| 182 | self.watcher = None |
| 183 | |
| 184 | def fileno(self): |
| 185 | raise NotImplementedError("fileno()") |
| 186 | |
| 187 | def close(self): |
| 188 | pass |
| 189 | |
| 190 | class sockbuffer(channel): |
| 191 | def __init__(self, socket, **kwargs): |
| 192 | super().__init__(**kwargs) |
| 193 | self.sk = socket |
| 194 | self.eof = False |
| 195 | self.obuf = bytearray() |
| 196 | |
| 197 | def fileno(self): |
| 198 | return self.sk.fileno() |
| 199 | |
| 200 | def close(self): |
| 201 | self.sk.close() |
| 202 | |
| 203 | def gotdata(self, data): |
| 204 | if data == b"": |
| 205 | self.eof = True |
| 206 | |
| 207 | def send(self, data, eof=False): |
| 208 | self.obuf.extend(data) |
| 209 | if eof: |
| 210 | self.eof = True |
| 211 | if self.watcher is not None: |
| 212 | self.watcher.update(self, True) |
| 213 | |
| 214 | @property |
| 215 | def readable(self): |
| 216 | return not self.eof |
| 217 | def read(self): |
| 218 | try: |
| 219 | data = self.sk.recv(1024) |
| 220 | self.gotdata(data) |
| 221 | except IOError: |
| 222 | self.obuf[:] = b"" |
| 223 | self.eof = True |
| 224 | |
| 225 | @property |
| 226 | def writable(self): |
| 227 | return bool(self.obuf); |
| 228 | def write(self): |
| 229 | try: |
| 230 | ret = self.sk.send(self.obuf) |
| 231 | self.obuf[:ret] = b"" |
| 232 | except IOError: |
| 233 | self.obuf[:] = b"" |
| 234 | self.eof = True |
| 235 | |
| 236 | class callbuffer(channel): |
| 237 | def __init__(self, **kwargs): |
| 238 | super().__init__(**kwargs) |
| 239 | self.queue = [] |
| 240 | self.rp, self.wp = os.pipe() |
| 241 | self.lock = threading.Lock() |
| 242 | self.eof = False |
| 243 | |
| 244 | def fileno(self): |
| 245 | return self.rp |
| 246 | |
| 247 | def close(self): |
| 248 | with self.lock: |
| 249 | try: |
| 250 | if self.wp >= 0: |
| 251 | os.close(self.wp) |
| 252 | self.wp = -1 |
| 253 | finally: |
| 254 | if self.rp >= 0: |
| 255 | os.close(self.rp) |
| 256 | self.rp = -1 |
| 257 | |
| 258 | @property |
| 259 | def readable(self): |
| 260 | return not self.eof |
| 261 | def read(self): |
| 262 | with self.lock: |
| 263 | try: |
| 264 | data = os.read(self.rp, 1024) |
| 265 | if data == b"": |
| 266 | self.eof = True |
| 267 | except IOError: |
| 268 | self.eof = True |
| 269 | cbs = list(self.queue) |
| 270 | self.queue[:] = [] |
| 271 | for cb in cbs: |
| 272 | cb() |
| 273 | |
| 274 | writable = False |
| 275 | |
| 276 | def call(self, cb): |
| 277 | with self.lock: |
| 278 | if self.wp < 0: |
| 279 | raise Exception("stopped") |
| 280 | self.queue.append(cb) |
| 281 | os.write(self.wp, b"a") |
| 282 | |
| 283 | def stop(self): |
| 284 | with self.lock: |
| 285 | if self.wp >= 0: |
| 286 | os.close(self.wp) |
| 287 | self.wp = -1 |
| 288 | |
| 289 | def currentwatcher(io, current): |
| 290 | def check(io): |
| 291 | if not current: |
| 292 | io.stop() |
| 293 | io.loopcheck.add(check) |