#=============================================================================== # Copyright (C) 2011-2012 by Andrew Moffat # # Permission is hereby granted, free of charge, to any person obtaining a copy # of this software and associated documentation files (the "Software"), to deal # in the Software without restriction, including without limitation the rights # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell # copies of the Software, and to permit persons to whom the Software is # furnished to do so, subject to the following conditions: # # The above copyright notice and this permission notice shall be included in # all copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN # THE SOFTWARE. #=============================================================================== __version__ = "1.08" __project_url__ = "https://github.com/amoffat/sh" import platform if "windows" in platform.system().lower(): raise ImportError("sh %s is currently only supported on linux and osx. \ please install pbs 0.110 (http://pypi.python.org/pypi/pbs) for windows \ support." % __version__) import sys IS_PY3 = sys.version_info[0] == 3 import traceback import os import re from glob import glob as original_glob from types import ModuleType from functools import partial import inspect import time as _time from locale import getpreferredencoding DEFAULT_ENCODING = getpreferredencoding() or "utf-8" if IS_PY3: from io import StringIO from io import BytesIO as cStringIO from queue import Queue, Empty else: from StringIO import StringIO from cStringIO import OutputType as cStringIO from Queue import Queue, Empty IS_OSX = platform.system() == "Darwin" THIS_DIR = os.path.dirname(os.path.realpath(__file__)) import errno import warnings import pty import termios import signal import gc import select import atexit import threading import tty import fcntl import struct import resource from collections import deque import logging import weakref logging_enabled = False if IS_PY3: raw_input = input unicode = str basestring = str class ErrorReturnCode(Exception): truncate_cap = 750 def __init__(self, full_cmd, stdout, stderr): self.full_cmd = full_cmd self.stdout = stdout self.stderr = stderr if self.stdout is None: tstdout = "" else: tstdout = self.stdout[:self.truncate_cap] out_delta = len(self.stdout) - len(tstdout) if out_delta: tstdout += ("... (%d more, please see e.stdout)" % out_delta).encode() if self.stderr is None: tstderr = "" else: tstderr = self.stderr[:self.truncate_cap] err_delta = len(self.stderr) - len(tstderr) if err_delta: tstderr += ("... (%d more, please see e.stderr)" % err_delta).encode() msg = "\n\n RAN: %r\n\n STDOUT:\n%s\n\n STDERR:\n%s" %\ (full_cmd, tstdout.decode(DEFAULT_ENCODING), tstderr.decode(DEFAULT_ENCODING)) super(ErrorReturnCode, self).__init__(msg) class SignalException(ErrorReturnCode): pass SIGNALS_THAT_SHOULD_THROW_EXCEPTION = ( signal.SIGKILL, signal.SIGSEGV, signal.SIGTERM, signal.SIGINT, signal.SIGQUIT ) # we subclass AttributeError because: # https://github.com/ipython/ipython/issues/2577 # https://github.com/amoffat/sh/issues/97#issuecomment-10610629 class CommandNotFound(AttributeError): pass rc_exc_regex = re.compile("(ErrorReturnCode|SignalException)_(\d+)") rc_exc_cache = {} def get_rc_exc(rc): rc = int(rc) try: return rc_exc_cache[rc] except KeyError: pass if rc > 0: name = "ErrorReturnCode_%d" % rc exc = type(name, (ErrorReturnCode,), {}) else: name = "SignalException_%d" % abs(rc) exc = type(name, (SignalException,), {}) rc_exc_cache[rc] = exc return exc def which(program): def is_exe(fpath): return os.path.exists(fpath) and os.access(fpath, os.X_OK) fpath, fname = os.path.split(program) if fpath: if is_exe(program): return program else: if "PATH" not in os.environ: return None for path in os.environ["PATH"].split(os.pathsep): exe_file = os.path.join(path, program) if is_exe(exe_file): return exe_file return None def resolve_program(program): path = which(program) if not path: # our actual command might have a dash in it, but we can't call # that from python (we have to use underscores), so we'll check # if a dash version of our underscore command exists and use that # if it does if "_" in program: path = which(program.replace("_", "-")) if not path: return None return path # we add this thin wrapper to glob.glob because of a specific edge case where # glob does not expand to anything. for example, if you try to do # glob.glob("*.py") and there are no *.py files in the directory, glob.glob # returns an empty list. this empty list gets passed to the command, and # then the command fails with a misleading error message. this thin wrapper # ensures that if there is no expansion, we pass in the original argument, # so that when the command fails, the error message is clearer def glob(arg): return original_glob(arg) or arg class Logger(object): def __init__(self, name, context=None): self.name = name self.context = "%s" if context: self.context = "%s: %%s" % context self.log = logging.getLogger(name) def info(self, msg, *args): if not logging_enabled: return self.log.info(self.context, msg % args) def debug(self, msg, *args): if not logging_enabled: return self.log.debug(self.context, msg % args) def error(self, msg, *args): if not logging_enabled: return self.log.error(self.context, msg % args) def exception(self, msg, *args): if not logging_enabled: return self.log.exception(self.context, msg % args) class RunningCommand(object): def __init__(self, cmd, call_args, stdin, stdout, stderr): truncate = 20 if len(cmd) > truncate: logger_str = "command %r...(%d more) call_args %r" % \ (cmd[:truncate], len(cmd) - truncate, call_args) else: logger_str = "command %r call_args %r" % (cmd, call_args) self.log = Logger("command", logger_str) self.call_args = call_args self.cmd = cmd self.ran = " ".join(cmd) self.process = None # this flag is for whether or not we've handled the exit code (like # by raising an exception). this is necessary because .wait() is called # from multiple places, and wait() triggers the exit code to be # processed. but we don't want to raise multiple exceptions, only # one (if any at all) self._handled_exit_code = False self.should_wait = True spawn_process = True # with contexts shouldn't run at all yet, they prepend # to every command in the context if call_args["with"]: spawn_process = False Command._prepend_stack.append(self) if callable(call_args["out"]) or callable(call_args["err"]): self.should_wait = False if call_args["piped"] or call_args["iter"] or call_args["iter_noblock"]: self.should_wait = False # we're running in the background, return self and let us lazily # evaluate if call_args["bg"]: self.should_wait = False # redirection if call_args["err_to_out"]: stderr = STDOUT # set up which stream should write to the pipe # TODO, make pipe None by default and limit the size of the Queue # in oproc.OProc pipe = STDOUT if call_args["iter"] == "out" or call_args["iter"] is True: pipe = STDOUT elif call_args["iter"] == "err": pipe = STDERR if call_args["iter_noblock"] == "out" or call_args["iter_noblock"] is True: pipe = STDOUT elif call_args["iter_noblock"] == "err": pipe = STDERR if spawn_process: self.log.debug("starting process") self.process = OProc(cmd, stdin, stdout, stderr, self.call_args, pipe=pipe) if self.should_wait: self.wait() def wait(self): self._handle_exit_code(self.process.wait()) return self # here we determine if we had an exception, or an error code that we weren't # expecting to see. if we did, we create and raise an exception def _handle_exit_code(self, code): if self._handled_exit_code: return self._handled_exit_code = True if code not in self.call_args["ok_code"] and \ (code > 0 or -code in SIGNALS_THAT_SHOULD_THROW_EXCEPTION): raise get_rc_exc(code)( " ".join(self.cmd), self.process.stdout, self.process.stderr ) @property def stdout(self): self.wait() return self.process.stdout @property def stderr(self): self.wait() return self.process.stderr @property def exit_code(self): self.wait() return self.process.exit_code @property def pid(self): return self.process.pid def __len__(self): return len(str(self)) def __enter__(self): # we don't actually do anything here because anything that should # have been done would have been done in the Command.__call__ call. # essentially all that has to happen is the comand be pushed on # the prepend stack. pass def __iter__(self): return self def next(self): # we do this because if get blocks, we can't catch a KeyboardInterrupt # so the slight timeout allows for that. while True: try: chunk = self.process._pipe_queue.get(False, .001) except Empty: if self.call_args["iter_noblock"]: return errno.EWOULDBLOCK else: if chunk is None: self.wait() raise StopIteration() try: return chunk.decode(self.call_args["encoding"], self.call_args["decode_errors"]) except UnicodeDecodeError: return chunk # python 3 __next__ = next def __exit__(self, typ, value, traceback): if self.call_args["with"] and Command._prepend_stack: Command._prepend_stack.pop() def __str__(self): if IS_PY3: return self.__unicode__() else: return unicode(self).encode(self.call_args["encoding"]) def __unicode__(self): if self.process and self.stdout: return self.stdout.decode(self.call_args["encoding"], self.call_args["decode_errors"]) return "" def __eq__(self, other): return unicode(self) == unicode(other) def __contains__(self, item): return item in str(self) def __getattr__(self, p): # let these three attributes pass through to the OProc object if p in ("signal", "terminate", "kill"): if self.process: return getattr(self.process, p) else: raise AttributeError return getattr(unicode(self), p) def __repr__(self): try: return str(self) except UnicodeDecodeError: if self.process: if self.stdout: return repr(self.stdout) return repr("") def __long__(self): return long(str(self).strip()) def __float__(self): return float(str(self).strip()) def __int__(self): return int(str(self).strip()) class Command(object): _prepend_stack = [] _call_args = { # currently unsupported #"fg": False, # run command in foreground "bg": False, # run command in background "with": False, # prepend the command to every command after it "in": None, "out": None, # redirect STDOUT "err": None, # redirect STDERR "err_to_out": None, # redirect STDERR to STDOUT # stdin buffer size # 1 for line, 0 for unbuffered, any other number for that amount "in_bufsize": 0, # stdout buffer size, same values as above "out_bufsize": 1, "err_bufsize": 1, # this is how big the output buffers will be for stdout and stderr. # this is essentially how much output they will store from the process. # we use a deque, so if it overflows past this amount, the first items # get pushed off as each new item gets added. # # NOTICE # this is not a *BYTE* size, this is a *CHUNK* size...meaning, that if # you're buffering out/err at 1024 bytes, the internal buffer size will # be "internal_bufsize" CHUNKS of 1024 bytes "internal_bufsize": 3 * 1024**2, "env": None, "piped": None, "iter": None, "iter_noblock": None, "ok_code": 0, "cwd": None, "long_sep": "=", # this is for programs that expect their input to be from a terminal. # ssh is one of those programs "tty_in": False, "tty_out": True, "encoding": DEFAULT_ENCODING, "decode_errors": "strict", # how long the process should run before it is auto-killed "timeout": 0, # these control whether or not stdout/err will get aggregated together # as the process runs. this has memory usage implications, so sometimes # with long-running processes with a lot of data, it makes sense to # set these to true "no_out": False, "no_err": False, "no_pipe": False, # if any redirection is used for stdout or stderr, internal buffering # of that data is not stored. this forces it to be stored, as if # the output is being T'd to both the redirected destination and our # internal buffers "tee": None, } # these are arguments that cannot be called together, because they wouldn't # make any sense _incompatible_call_args = ( #("fg", "bg", "Command can't be run in the foreground and background"), ("err", "err_to_out", "Stderr is already being redirected"), ("piped", "iter", "You cannot iterate when this command is being piped"), ) # this method exists because of the need to have some way of letting # manual object instantiation not perform the underscore-to-dash command # conversion that resolve_program uses. # # there are 2 ways to create a Command object. using sh.Command() # or by using sh.. the method fed into sh.Command must be taken # literally, and so no underscore-dash conversion is performed. the one # for sh. must do the underscore-dash converesion, because we # can't type dashes in method names @classmethod def _create(cls, program, **default_kwargs): path = resolve_program(program) if not path: raise CommandNotFound(program) cmd = cls(path) if default_kwargs: cmd = cmd.bake(**default_kwargs) return cmd def __init__(self, path): path = which(path) if not path: raise CommandNotFound(path) self._path = path self._partial = False self._partial_baked_args = [] self._partial_call_args = {} # bugfix for functools.wraps. issue #121 self.__name__ = repr(self) def __getattribute__(self, name): # convenience getattr = partial(object.__getattribute__, self) if name.startswith("_"): return getattr(name) if name == "bake": return getattr("bake") if name.endswith("_"): name = name[:-1] return getattr("bake")(name) @staticmethod def _extract_call_args(kwargs, to_override={}): kwargs = kwargs.copy() call_args = {} for parg, default in Command._call_args.items(): key = "_" + parg if key in kwargs: call_args[parg] = kwargs[key] del kwargs[key] elif parg in to_override: call_args[parg] = to_override[parg] # test for incompatible call args s1 = set(call_args.keys()) for args in Command._incompatible_call_args: args = list(args) error = args.pop() if s1.issuperset(args): raise TypeError("Invalid special arguments %r: %s" % (args, error)) return call_args, kwargs # this helper method is for normalizing an argument into a string in the # system's default encoding. we can feed it a number or a string or # whatever def _format_arg(self, arg): if IS_PY3: arg = str(arg) else: # if the argument is already unicode, or a number or whatever, # this first call will fail. try: arg = unicode(arg, DEFAULT_ENCODING).encode(DEFAULT_ENCODING) except TypeError: arg = unicode(arg).encode(DEFAULT_ENCODING) return arg def _aggregate_keywords(self, keywords, sep, raw=False): processed = [] for k, v in keywords.items(): # we're passing a short arg as a kwarg, example: # cut(d="\t") if len(k) == 1: if v is not False: processed.append("-" + k) if v is not True: processed.append(self._format_arg(v)) # we're doing a long arg else: if not raw: k = k.replace("_", "-") if v is True: processed.append("--" + k) elif v is False: pass else: processed.append("--%s%s%s" % (k, sep, self._format_arg(v))) return processed def _compile_args(self, args, kwargs, sep): processed_args = [] # aggregate positional args for arg in args: if isinstance(arg, (list, tuple)): if not arg: warnings.warn("Empty list passed as an argument to %r. \ If you're using glob.glob(), please use sh.glob() instead." % self.path, stacklevel=3) for sub_arg in arg: processed_args.append(self._format_arg(sub_arg)) elif isinstance(arg, dict): processed_args += self._aggregate_keywords(arg, sep, raw=True) else: processed_args.append(self._format_arg(arg)) # aggregate the keyword arguments processed_args += self._aggregate_keywords(kwargs, sep) return processed_args # TODO needs documentation def bake(self, *args, **kwargs): fn = Command(self._path) fn._partial = True call_args, kwargs = self._extract_call_args(kwargs) pruned_call_args = call_args for k,v in Command._call_args.items(): try: if pruned_call_args[k] == v: del pruned_call_args[k] except KeyError: continue fn._partial_call_args.update(self._partial_call_args) fn._partial_call_args.update(pruned_call_args) fn._partial_baked_args.extend(self._partial_baked_args) sep = pruned_call_args.get("long_sep", self._call_args["long_sep"]) fn._partial_baked_args.extend(self._compile_args(args, kwargs, sep)) return fn def __str__(self): if IS_PY3: return self.__unicode__() else: return unicode(self).encode(DEFAULT_ENCODING) def __eq__(self, other): try: return str(self) == str(other) except: return False def __repr__(self): return "" % str(self) def __unicode__(self): baked_args = " ".join(self._partial_baked_args) if baked_args: baked_args = " " + baked_args return self._path + baked_args def __enter__(self): self(_with=True) def __exit__(self, typ, value, traceback): Command._prepend_stack.pop() def __call__(self, *args, **kwargs): kwargs = kwargs.copy() args = list(args) cmd = [] # aggregate any 'with' contexts call_args = Command._call_args.copy() for prepend in self._prepend_stack: # don't pass the 'with' call arg pcall_args = prepend.call_args.copy() try: del pcall_args["with"] except: pass call_args.update(pcall_args) cmd.extend(prepend.cmd) cmd.append(self._path) # here we extract the special kwargs and override any # special kwargs from the possibly baked command tmp_call_args, kwargs = self._extract_call_args(kwargs, self._partial_call_args) call_args.update(tmp_call_args) if not isinstance(call_args["ok_code"], (tuple, list)): call_args["ok_code"] = [call_args["ok_code"]] # check if we're piping via composition stdin = call_args["in"] if args: first_arg = args.pop(0) if isinstance(first_arg, RunningCommand): # it makes sense that if the input pipe of a command is running # in the background, then this command should run in the # background as well if first_arg.call_args["bg"]: call_args["bg"] = True stdin = first_arg.process._pipe_queue else: args.insert(0, first_arg) processed_args = self._compile_args(args, kwargs, call_args["long_sep"]) # makes sure our arguments are broken up correctly split_args = self._partial_baked_args + processed_args final_args = split_args cmd.extend(final_args) # stdout redirection stdout = call_args["out"] if stdout \ and not callable(stdout) \ and not hasattr(stdout, "write") \ and not isinstance(stdout, (cStringIO, StringIO)): stdout = open(str(stdout), "wb") # stderr redirection stderr = call_args["err"] if stderr and not callable(stderr) and not hasattr(stderr, "write") \ and not isinstance(stderr, (cStringIO, StringIO)): stderr = open(str(stderr), "wb") return RunningCommand(cmd, call_args, stdin, stdout, stderr) # used in redirecting STDOUT = -1 STDERR = -2 # Process open = Popen # Open Process = OProc class OProc(object): _procs_to_cleanup = set() _registered_cleanup = False _default_window_size = (24, 80) def __init__(self, cmd, stdin, stdout, stderr, call_args, persist=False, pipe=STDOUT): self.call_args = call_args self._single_tty = self.call_args["tty_in"] and self.call_args["tty_out"] # this logic is a little convoluted, but basically this top-level # if/else is for consolidating input and output TTYs into a single # TTY. this is the only way some secure programs like ssh will # output correctly (is if stdout and stdin are both the same TTY) if self._single_tty: self._stdin_fd, self._slave_stdin_fd = pty.openpty() self._stdout_fd = self._stdin_fd self._slave_stdout_fd = self._slave_stdin_fd self._stderr_fd = self._stdin_fd self._slave_stderr_fd = self._slave_stdin_fd # do not consolidate stdin and stdout else: if self.call_args["tty_in"]: self._slave_stdin_fd, self._stdin_fd = pty.openpty() else: self._slave_stdin_fd, self._stdin_fd = os.pipe() # tty_out is usually the default if self.call_args["tty_out"]: self._stdout_fd, self._slave_stdout_fd = pty.openpty() else: self._stdout_fd, self._slave_stdout_fd = os.pipe() # unless STDERR is going to STDOUT, it ALWAYS needs to be a pipe, # and never a PTY. the reason for this is not totally clear to me, # but it has to do with the fact that if STDERR isn't set as the # CTTY (because STDOUT is), the STDERR buffer won't always flush # by the time the process exits, and the data will be lost. # i've only seen this on OSX. if stderr is not STDOUT: self._stderr_fd, self._slave_stderr_fd = os.pipe() gc_enabled = gc.isenabled() if gc_enabled: gc.disable() self.pid = os.fork() # child if self.pid == 0: # this piece of ugliness is due to a bug where we can lose output # if we do os.close(self._slave_stdout_fd) in the parent after # the child starts writing. # see http://bugs.python.org/issue15898 if IS_OSX and IS_PY3: _time.sleep(0.01) os.setsid() if self.call_args["tty_out"]: # set raw mode, so there isn't any weird translation of newlines # to \r\n and other oddities. we're not outputting to a terminal # anyways # # we HAVE to do this here, and not in the parent thread, because # we have to guarantee that this is set before the child process # is run, and we can't do it twice. tty.setraw(self._stdout_fd) os.close(self._stdin_fd) if not self._single_tty: os.close(self._stdout_fd) if stderr is not STDOUT: os.close(self._stderr_fd) if self.call_args["cwd"]: os.chdir(self.call_args["cwd"]) os.dup2(self._slave_stdin_fd, 0) os.dup2(self._slave_stdout_fd, 1) # we're not directing stderr to stdout? then set self._slave_stderr_fd to # fd 2, the common stderr fd if stderr is STDOUT: os.dup2(self._slave_stdout_fd, 2) else: os.dup2(self._slave_stderr_fd, 2) # don't inherit file descriptors max_fd = resource.getrlimit(resource.RLIMIT_NOFILE)[0] os.closerange(3, max_fd) # set our controlling terminal if self.call_args["tty_out"]: tmp_fd = os.open(os.ttyname(1), os.O_RDWR) os.close(tmp_fd) if self.call_args["tty_out"]: self.setwinsize(1) # actually execute the process if self.call_args["env"] is None: os.execv(cmd[0], cmd) else: os.execve(cmd[0], cmd, self.call_args["env"]) os._exit(255) # parent else: if gc_enabled: gc.enable() if not OProc._registered_cleanup: atexit.register(OProc._cleanup_procs) OProc._registered_cleanup = True self.started = _time.time() self.cmd = cmd self.exit_code = None self.stdin = stdin or Queue() self._pipe_queue = Queue() # this is used to prevent a race condition when we're waiting for # a process to end, and the OProc's internal threads are also checking # for the processes's end self._wait_lock = threading.Lock() # these are for aggregating the stdout and stderr. we use a deque # because we don't want to overflow self._stdout = deque(maxlen=self.call_args["internal_bufsize"]) self._stderr = deque(maxlen=self.call_args["internal_bufsize"]) if self.call_args["tty_in"]: self.setwinsize(self._stdin_fd) self.log = Logger("process", repr(self)) os.close(self._slave_stdin_fd) if not self._single_tty: os.close(self._slave_stdout_fd) if stderr is not STDOUT: os.close(self._slave_stderr_fd) self.log.debug("started process") if not persist: OProc._procs_to_cleanup.add(self) if self.call_args["tty_in"]: attr = termios.tcgetattr(self._stdin_fd) attr[3] &= ~termios.ECHO termios.tcsetattr(self._stdin_fd, termios.TCSANOW, attr) # this represents the connection from a Queue object (or whatever # we're using to feed STDIN) to the process's STDIN fd self._stdin_stream = StreamWriter("stdin", self, self._stdin_fd, self.stdin, self.call_args["in_bufsize"]) stdout_pipe = None if pipe is STDOUT and not self.call_args["no_pipe"]: stdout_pipe = self._pipe_queue # this represents the connection from a process's STDOUT fd to # wherever it has to go, sometimes a pipe Queue (that we will use # to pipe data to other processes), and also an internal deque # that we use to aggregate all the output save_stdout = not self.call_args["no_out"] and \ (self.call_args["tee"] in (True, "out") or stdout is None) self._stdout_stream = StreamReader("stdout", self, self._stdout_fd, stdout, self._stdout, self.call_args["out_bufsize"], stdout_pipe, save_data=save_stdout) if stderr is STDOUT or self._single_tty: self._stderr_stream = None else: stderr_pipe = None if pipe is STDERR and not self.call_args["no_pipe"]: stderr_pipe = self._pipe_queue save_stderr = not self.call_args["no_err"] and \ (self.call_args["tee"] in ("err",) or stderr is None) self._stderr_stream = StreamReader("stderr", self, self._stderr_fd, stderr, self._stderr, self.call_args["err_bufsize"], stderr_pipe, save_data=save_stderr) # start the main io threads self._input_thread = self._start_thread(self.input_thread, self._stdin_stream) self._output_thread = self._start_thread(self.output_thread, self._stdout_stream, self._stderr_stream) def __repr__(self): return "" % (self.pid, self.cmd[:500]) # also borrowed from pexpect.py @staticmethod def setwinsize(fd): rows, cols = OProc._default_window_size TIOCSWINSZ = getattr(termios, 'TIOCSWINSZ', -2146929561) if TIOCSWINSZ == 2148037735: # L is not required in Python >= 2.2. TIOCSWINSZ = -2146929561 # Same bits, but with sign. s = struct.pack('HHHH', rows, cols, 0, 0) fcntl.ioctl(fd, TIOCSWINSZ, s) @staticmethod def _start_thread(fn, *args): thrd = threading.Thread(target=fn, args=args) thrd.daemon = True thrd.start() return thrd def in_bufsize(self, buf): self._stdin_stream.stream_bufferer.change_buffering(buf) def out_bufsize(self, buf): self._stdout_stream.stream_bufferer.change_buffering(buf) def err_bufsize(self, buf): if self._stderr_stream: self._stderr_stream.stream_bufferer.change_buffering(buf) def input_thread(self, stdin): done = False while not done and self.alive: self.log.debug("%r ready for more input", stdin) done = stdin.write() stdin.close() def output_thread(self, stdout, stderr): readers = [] errors = [] if stdout is not None: readers.append(stdout) errors.append(stdout) if stderr is not None: readers.append(stderr) errors.append(stderr) while readers: outputs, inputs, err = select.select(readers, [], errors, 0.1) # stdout and stderr for stream in outputs: self.log.debug("%r ready to be read from", stream) done = stream.read() if done: readers.remove(stream) for stream in err: pass # test if the process has been running too long if self.call_args["timeout"]: now = _time.time() if now - self.started > self.call_args["timeout"]: self.log.debug("we've been running too long") self.kill() # this is here because stdout may be the controlling TTY, and # we can't close it until the process has ended, otherwise the # child will get SIGHUP. typically, if we've broken out of # the above loop, and we're here, the process is just about to # end, so it's probably ok to aggressively poll self.alive # # the other option to this would be to do the CTTY close from # the method that does the actual os.waitpid() call, but the # problem with that is that the above loop might still be # running, and closing the fd will cause some operation to # fail. this is less complex than wrapping all the ops # in the above loop with out-of-band fd-close exceptions while self.alive: _time.sleep(0.001) if stdout: stdout.close() if stderr: stderr.close() @property def stdout(self): return "".encode(self.call_args["encoding"]).join(self._stdout) @property def stderr(self): return "".encode(self.call_args["encoding"]).join(self._stderr) def signal(self, sig): self.log.debug("sending signal %d", sig) try: os.kill(self.pid, sig) except OSError: pass def kill(self): self.log.debug("killing") self.signal(signal.SIGKILL) def terminate(self): self.log.debug("terminating") self.signal(signal.SIGTERM) @staticmethod def _cleanup_procs(): for proc in OProc._procs_to_cleanup: proc.kill() def _handle_exit_code(self, exit_code): # if we exited from a signal, let our exit code reflect that if os.WIFSIGNALED(exit_code): return -os.WTERMSIG(exit_code) # otherwise just give us a normal exit code elif os.WIFEXITED(exit_code): return os.WEXITSTATUS(exit_code) else: raise RuntimeError("Unknown child exit status!") @property def alive(self): if self.exit_code is not None: return False # what we're doing here essentially is making sure that the main thread # (or another thread), isn't calling .wait() on the process. because # .wait() calls os.waitpid(self.pid, 0), we can't do an os.waitpid # here...because if we did, and the process exited while in this # thread, the main thread's os.waitpid(self.pid, 0) would raise OSError # (because the process ended in another thread). # # so essentially what we're doing is, using this lock, checking if # we're calling .wait(), and if we are, let .wait() get the exit code # and handle the status, otherwise let us do it. acquired = self._wait_lock.acquire(False) if not acquired: if self.exit_code is not None: return False return True try: # WNOHANG is just that...we're calling waitpid without hanging... # essentially polling the process pid, exit_code = os.waitpid(self.pid, os.WNOHANG) if pid == self.pid: self.exit_code = self._handle_exit_code(exit_code) return False # no child process except OSError: return False else: return True finally: self._wait_lock.release() def wait(self): self.log.debug("acquiring wait lock to wait for completion") with self._wait_lock: self.log.debug("got wait lock") if self.exit_code is None: self.log.debug("exit code not set, waiting on pid") pid, exit_code = os.waitpid(self.pid, 0) self.exit_code = self._handle_exit_code(exit_code) else: self.log.debug("exit code already set (%d), no need to wait", self.exit_code) self._input_thread.join() self._output_thread.join() OProc._procs_to_cleanup.discard(self) return self.exit_code class DoneReadingStdin(Exception): pass class NoStdinData(Exception): pass # this guy is for reading from some input (the stream) and writing to our # opened process's stdin fd. the stream can be a Queue, a callable, something # with the "read" method, a string, or an iterable class StreamWriter(object): def __init__(self, name, process, stream, stdin, bufsize): self.name = name self.process = weakref.ref(process) self.stream = stream self.stdin = stdin self.log = Logger("streamwriter", repr(self)) self.stream_bufferer = StreamBufferer(self.process().call_args["encoding"], bufsize) # determine buffering for reading from the input we set for stdin if bufsize == 1: self.bufsize = 1024 elif bufsize == 0: self.bufsize = 1 else: self.bufsize = bufsize if isinstance(stdin, Queue): log_msg = "queue" self.get_chunk = self.get_queue_chunk elif callable(stdin): log_msg = "callable" self.get_chunk = self.get_callable_chunk # also handles stringio elif hasattr(stdin, "read"): log_msg = "file descriptor" self.get_chunk = self.get_file_chunk elif isinstance(stdin, basestring): log_msg = "string" if bufsize == 1: # TODO, make the split() be a generator self.stdin = iter((c+"\n" for c in stdin.split("\n"))) else: self.stdin = iter(stdin[i:i+self.bufsize] for i in range(0, len(stdin), self.bufsize)) self.get_chunk = self.get_iter_chunk else: log_msg = "general iterable" self.stdin = iter(stdin) self.get_chunk = self.get_iter_chunk self.log.debug("parsed stdin as a %s", log_msg) def __repr__(self): return "" % (self.name, self.process()) def fileno(self): return self.stream def get_queue_chunk(self): try: chunk = self.stdin.get(True, 0.01) except Empty: raise NoStdinData if chunk is None: raise DoneReadingStdin return chunk def get_callable_chunk(self): try: return self.stdin() except: raise DoneReadingStdin def get_iter_chunk(self): try: if IS_PY3: return self.stdin.__next__() else: return self.stdin.next() except StopIteration: raise DoneReadingStdin def get_file_chunk(self): if self.stream_bufferer.type == 1: chunk = self.stdin.readline() else: chunk = self.stdin.read(self.bufsize) if not chunk: raise DoneReadingStdin else: return chunk # the return value answers the questions "are we done writing forever?" def write(self): # get_chunk may sometimes return bytes, and sometimes returns trings # because of the nature of the different types of STDIN objects we # support try: chunk = self.get_chunk() except DoneReadingStdin: self.log.debug("done reading") if self.process().call_args["tty_in"]: # EOF time try: char = termios.tcgetattr(self.stream)[6][termios.VEOF] except: char = chr(4).encode() os.write(self.stream, char) return True except NoStdinData: self.log.debug("received no data") return False # if we're not bytes, make us bytes if IS_PY3 and hasattr(chunk, "encode"): chunk = chunk.encode(self.process().call_args["encoding"]) for chunk in self.stream_bufferer.process(chunk): self.log.debug("got chunk size %d: %r", len(chunk), chunk[:30]) self.log.debug("writing chunk to process") try: os.write(self.stream, chunk) except OSError: self.log.debug("OSError writing stdin chunk") return True def close(self): self.log.debug("closing, but flushing first") chunk = self.stream_bufferer.flush() self.log.debug("got chunk size %d to flush: %r", len(chunk), chunk[:30]) try: if chunk: os.write(self.stream, chunk) if not self.process().call_args["tty_in"]: self.log.debug("we used a TTY, so closing the stream") os.close(self.stream) except OSError: pass class StreamReader(object): def __init__(self, name, process, stream, handler, buffer, bufsize, pipe_queue=None, save_data=True): self.name = name self.process = weakref.ref(process) self.stream = stream self.buffer = buffer self.save_data = save_data self.encoding = process.call_args["encoding"] self.decode_errors = process.call_args["decode_errors"] self.pipe_queue = None if pipe_queue: self.pipe_queue = weakref.ref(pipe_queue) self.log = Logger("streamreader", repr(self)) self.stream_bufferer = StreamBufferer(self.encoding, bufsize, self.decode_errors) # determine buffering if bufsize == 1: self.bufsize = 1024 elif bufsize == 0: self.bufsize = 1 else: self.bufsize = bufsize # here we're determining the handler type by doing some basic checks # on the handler object self.handler = handler if callable(handler): self.handler_type = "fn" elif isinstance(handler, StringIO): self.handler_type = "stringio" elif isinstance(handler, cStringIO): self.handler_type = "cstringio" elif hasattr(handler, "write"): self.handler_type = "fd" else: self.handler_type = None self.should_quit = False # here we choose how to call the callback, depending on how many # arguments it takes. the reason for this is to make it as easy as # possible for people to use, without limiting them. a new user will # assume the callback takes 1 argument (the data). as they get more # advanced, they may want to terminate the process, or pass some stdin # back, and will realize that they can pass a callback of more args if self.handler_type == "fn": implied_arg = 0 if inspect.ismethod(handler): implied_arg = 1 num_args = len(inspect.getargspec(handler).args) else: if inspect.isfunction(handler): num_args = len(inspect.getargspec(handler).args) # is an object instance with __call__ method else: implied_arg = 1 num_args = len(inspect.getargspec(handler.__call__).args) self.handler_args = () if num_args == implied_arg + 2: self.handler_args = (self.process().stdin,) elif num_args == implied_arg + 3: self.handler_args = (self.process().stdin, self.process) def fileno(self): return self.stream def __repr__(self): return "" % (self.name, self.process()) def close(self): chunk = self.stream_bufferer.flush() self.log.debug("got chunk size %d to flush: %r", len(chunk), chunk[:30]) if chunk: self.write_chunk(chunk) if self.handler_type == "fd" and hasattr(self.handler, "close"): self.handler.flush() if self.pipe_queue and self.save_data: self.pipe_queue().put(None) try: os.close(self.stream) except OSError: pass def write_chunk(self, chunk): # in PY3, the chunk coming in will be bytes, so keep that in mind if self.handler_type == "fn" and not self.should_quit: # try to use the encoding first, if that doesn't work, send # the bytes, because it might be binary try: to_handler = chunk.decode(self.encoding, self.decode_errors) except UnicodeDecodeError: to_handler = chunk # this is really ugly, but we can't store self.process as one of # the handler args in self.handler_args, the reason being is that # it would create cyclic references, and prevent objects from # being garbage collected. so we're determining if this handler # even requires self.process (by the argument count), and if it # does, resolving the weakref to a hard reference and passing # that into the handler handler_args = self.handler_args if len(self.handler_args) == 2: handler_args = (self.handler_args[0], self.process()) self.should_quit = self.handler(to_handler, *handler_args) elif self.handler_type == "stringio": self.handler.write(chunk.decode(self.encoding, self.decode_errors)) elif self.handler_type in ("cstringio", "fd"): self.handler.write(chunk) if self.save_data: self.buffer.append(chunk) if self.pipe_queue: self.log.debug("putting chunk onto pipe: %r", chunk[:30]) self.pipe_queue().put(chunk) def read(self): # if we're PY3, we're reading bytes, otherwise we're reading # str try: chunk = os.read(self.stream, self.bufsize) except OSError as e: self.log.debug("got errno %d, done reading", e.errno) return True if not chunk: self.log.debug("got no chunk, done reading") return True self.log.debug("got chunk size %d: %r", len(chunk), chunk[:30]) for chunk in self.stream_bufferer.process(chunk): self.write_chunk(chunk) # this is used for feeding in chunks of stdout/stderr, and breaking it up into # chunks that will actually be put into the internal buffers. for example, if # you have two processes, one being piped to the other, and you want that, # first process to feed lines of data (instead of the chunks however they # come in), OProc will use an instance of this class to chop up the data and # feed it as lines to be sent down the pipe class StreamBufferer(object): def __init__(self, encoding=DEFAULT_ENCODING, buffer_type=1, decode_errors="strict"): # 0 for unbuffered, 1 for line, everything else for that amount self.type = buffer_type self.buffer = [] self.n_buffer_count = 0 self.encoding = encoding self.decode_errors = decode_errors # this is for if we change buffering types. if we change from line # buffered to unbuffered, its very possible that our self.buffer list # has data that was being saved up (while we searched for a newline). # we need to use that up, so we don't lose it self._use_up_buffer_first = False # the buffering lock is used because we might chance the buffering # types from a different thread. for example, if we have a stdout # callback, we might use it to change the way stdin buffers. so we # lock self._buffering_lock = threading.RLock() self.log = Logger("stream_bufferer") def change_buffering(self, new_type): # TODO, when we stop supporting 2.6, make this a with context self.log.debug("acquiring buffering lock for changing buffering") self._buffering_lock.acquire() self.log.debug("got buffering lock for changing buffering") try: if new_type == 0: self._use_up_buffer_first = True self.type = new_type finally: self._buffering_lock.release() self.log.debug("released buffering lock for changing buffering") def process(self, chunk): # MAKE SURE THAT THE INPUT IS PY3 BYTES # THE OUTPUT IS ALWAYS PY3 BYTES # TODO, when we stop supporting 2.6, make this a with context self.log.debug("acquiring buffering lock to process chunk (buffering: %d)", self.type) self._buffering_lock.acquire() self.log.debug("got buffering lock to process chunk (buffering: %d)", self.type) try: # we've encountered binary, permanently switch to N size buffering # since matching on newline doesn't make sense anymore if self.type == 1: try: chunk.decode(self.encoding, self.decode_errors) except: self.log.debug("detected binary data, changing buffering") self.change_buffering(1024) # unbuffered if self.type == 0: if self._use_up_buffer_first: self._use_up_buffer_first = False to_write = self.buffer self.buffer = [] to_write.append(chunk) return to_write return [chunk] # line buffered elif self.type == 1: total_to_write = [] chunk = chunk.decode(self.encoding, self.decode_errors) while True: newline = chunk.find("\n") if newline == -1: break chunk_to_write = chunk[:newline+1] if self.buffer: # this is ugly, but it's designed to take the existing # bytes buffer, join it together, tack on our latest # chunk, then convert the whole thing to a string. # it's necessary, i'm sure. read the whole block to # see why. chunk_to_write = "".encode(self.encoding).join(self.buffer) \ + chunk_to_write.encode(self.encoding) chunk_to_write = chunk_to_write.decode(self.encoding) self.buffer = [] self.n_buffer_count = 0 chunk = chunk[newline+1:] total_to_write.append(chunk_to_write.encode(self.encoding)) if chunk: self.buffer.append(chunk.encode(self.encoding)) self.n_buffer_count += len(chunk) return total_to_write # N size buffered else: total_to_write = [] while True: overage = self.n_buffer_count + len(chunk) - self.type if overage >= 0: ret = "".encode(self.encoding).join(self.buffer) + chunk chunk_to_write = ret[:self.type] chunk = ret[self.type:] total_to_write.append(chunk_to_write) self.buffer = [] self.n_buffer_count = 0 else: self.buffer.append(chunk) self.n_buffer_count += len(chunk) break return total_to_write finally: self._buffering_lock.release() self.log.debug("released buffering lock for processing chunk (buffering: %d)", self.type) def flush(self): self.log.debug("acquiring buffering lock for flushing buffer") self._buffering_lock.acquire() self.log.debug("got buffering lock for flushing buffer") try: ret = "".encode(self.encoding).join(self.buffer) self.buffer = [] return ret finally: self._buffering_lock.release() self.log.debug("released buffering lock for flushing buffer") # this allows lookups to names that aren't found in the global scope to be # searched for as a program name. for example, if "ls" isn't found in this # module's scope, we consider it a system program and try to find it. # # we use a dict instead of just a regular object as the base class because # the exec() statement used in this file requires the "globals" argument to # be a dictionary class Environment(dict): def __init__(self, globs, baked_args={}): self.globs = globs self.baked_args = baked_args def __setitem__(self, k, v): self.globs[k] = v def __getitem__(self, k): try: return self.globs[k] except KeyError: pass # the only way we'd get to here is if we've tried to # import * from a repl. so, raise an exception, since # that's really the only sensible thing to do if k == "__all__": raise ImportError("Cannot import * from sh. \ Please import sh or import programs individually.") # if we end with "_" just go ahead and skip searching # our namespace for python stuff. this was mainly for the # command "id", which is a popular program for finding # if a user exists, but also a python function for getting # the address of an object. so can call the python # version by "id" and the program version with "id_" if not k.endswith("_"): # check if we're naming a dynamically generated ReturnCode exception try: return rc_exc_cache[k] except KeyError: m = rc_exc_regex.match(k) if m: exit_code = int(m.group(2)) if m.group(1) == "SignalException": exit_code = -exit_code return get_rc_exc(exit_code) # is it a builtin? try: return getattr(self["__builtins__"], k) except AttributeError: pass elif not k.startswith("_"): k = k.rstrip("_") # https://github.com/ipython/ipython/issues/2577 # https://github.com/amoffat/sh/issues/97#issuecomment-10610629 if k.startswith("__") and k.endswith("__"): raise AttributeError # how about an environment variable? try: return os.environ[k] except KeyError: pass # is it a custom builtin? builtin = getattr(self, "b_"+k, None) if builtin: return builtin # it must be a command then # we use _create instead of instantiating the class directly because # _create uses resolve_program, which will automatically do underscore- # to-dash conversions. instantiating directly does not use that return Command._create(k, **self.baked_args) # methods that begin with "b_" are custom builtins and will override any # program that exists in our path. this is useful for things like # common shell builtins that people are used to, but which aren't actually # full-fledged system binaries def b_cd(self, path): os.chdir(path) def b_which(self, program): return which(program) def run_repl(env): banner = "\n>> sh v{version}\n>> https://github.com/amoffat/sh\n" print(banner.format(version=__version__)) while True: try: line = raw_input("sh> ") except (ValueError, EOFError): break try: exec(compile(line, "", "single"), env, env) except SystemExit: break except: print(traceback.format_exc()) # cleans up our last line print("") # this is a thin wrapper around THIS module (we patch sys.modules[__name__]). # this is in the case that the user does a "from sh import whatever" # in other words, they only want to import certain programs, not the whole # system PATH worth of commands. in this case, we just proxy the # import lookup to our Environment class class SelfWrapper(ModuleType): def __init__(self, self_module, baked_args={}): # this is super ugly to have to copy attributes like this, # but it seems to be the only way to make reload() behave # nicely. if i make these attributes dynamic lookups in # __getattr__, reload sometimes chokes in weird ways... for attr in ["__builtins__", "__doc__", "__name__", "__package__"]: setattr(self, attr, getattr(self_module, attr, None)) # python 3.2 (2.7 and 3.3 work fine) breaks on osx (not ubuntu) # if we set this to None. and 3.3 needs a value for __path__ self.__path__ = [] self.self_module = self_module self.env = Environment(globals(), baked_args) def __setattr__(self, name, value): if hasattr(self, "env"): self.env[name] = value ModuleType.__setattr__(self, name, value) def __getattr__(self, name): if name == "env": raise AttributeError return self.env[name] # accept special keywords argument to define defaults for all operations # that will be processed with given by return SelfWrapper def __call__(self, **kwargs): return SelfWrapper(self.self_module, kwargs) # we're being run as a stand-alone script if __name__ == "__main__": try: arg = sys.argv.pop(1) except: arg = None if arg == "test": import subprocess def run_test(version): py_version = "python%s" % version py_bin = which(py_version) if py_bin: print("Testing %s" % py_version.capitalize()) p = subprocess.Popen([py_bin, os.path.join(THIS_DIR, "test.py")] + sys.argv[1:]) p.wait() else: print("Couldn't find %s, skipping" % py_version.capitalize()) versions = ("2.6", "2.7", "3.1", "3.2", "3.3") for version in versions: run_test(version) else: env = Environment(globals()) run_repl(env) # we're being imported from somewhere else: self = sys.modules[__name__] sys.modules[__name__] = SelfWrapper(self)