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diff --git a/lib-python/2.7/subprocess.py b/lib-python/2.7/subprocess.py new file mode 100644 index 0000000000..24bf321827 --- /dev/null +++ b/lib-python/2.7/subprocess.py @@ -0,0 +1,1462 @@ +# subprocess - Subprocesses with accessible I/O streams +# +# For more information about this module, see PEP 324. +# +# This module should remain compatible with Python 2.2, see PEP 291. +# +# Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se> +# +# Licensed to PSF under a Contributor Agreement. +# See http://www.python.org/2.4/license for licensing details. + +r"""subprocess - Subprocesses with accessible I/O streams + +This module allows you to spawn processes, connect to their +input/output/error pipes, and obtain their return codes. This module +intends to replace several other, older modules and functions, like: + +os.system +os.spawn* +os.popen* +popen2.* +commands.* + +Information about how the subprocess module can be used to replace these +modules and functions can be found below. + + + +Using the subprocess module +=========================== +This module defines one class called Popen: + +class Popen(args, bufsize=0, executable=None, + stdin=None, stdout=None, stderr=None, + preexec_fn=None, close_fds=False, shell=False, + cwd=None, env=None, universal_newlines=False, + startupinfo=None, creationflags=0): + + +Arguments are: + +args should be a string, or a sequence of program arguments. The +program to execute is normally the first item in the args sequence or +string, but can be explicitly set by using the executable argument. + +On UNIX, with shell=False (default): In this case, the Popen class +uses os.execvp() to execute the child program. args should normally +be a sequence. A string will be treated as a sequence with the string +as the only item (the program to execute). + +On UNIX, with shell=True: If args is a string, it specifies the +command string to execute through the shell. If args is a sequence, +the first item specifies the command string, and any additional items +will be treated as additional shell arguments. + +On Windows: the Popen class uses CreateProcess() to execute the child +program, which operates on strings. If args is a sequence, it will be +converted to a string using the list2cmdline method. Please note that +not all MS Windows applications interpret the command line the same +way: The list2cmdline is designed for applications using the same +rules as the MS C runtime. + +bufsize, if given, has the same meaning as the corresponding argument +to the built-in open() function: 0 means unbuffered, 1 means line +buffered, any other positive value means use a buffer of +(approximately) that size. A negative bufsize means to use the system +default, which usually means fully buffered. The default value for +bufsize is 0 (unbuffered). + +stdin, stdout and stderr specify the executed programs' standard +input, standard output and standard error file handles, respectively. +Valid values are PIPE, an existing file descriptor (a positive +integer), an existing file object, and None. PIPE indicates that a +new pipe to the child should be created. With None, no redirection +will occur; the child's file handles will be inherited from the +parent. Additionally, stderr can be STDOUT, which indicates that the +stderr data from the applications should be captured into the same +file handle as for stdout. + +If preexec_fn is set to a callable object, this object will be called +in the child process just before the child is executed. + +If close_fds is true, all file descriptors except 0, 1 and 2 will be +closed before the child process is executed. + +if shell is true, the specified command will be executed through the +shell. + +If cwd is not None, the current directory will be changed to cwd +before the child is executed. + +If env is not None, it defines the environment variables for the new +process. + +If universal_newlines is true, the file objects stdout and stderr are +opened as a text files, but lines may be terminated by any of '\n', +the Unix end-of-line convention, '\r', the Macintosh convention or +'\r\n', the Windows convention. All of these external representations +are seen as '\n' by the Python program. Note: This feature is only +available if Python is built with universal newline support (the +default). Also, the newlines attribute of the file objects stdout, +stdin and stderr are not updated by the communicate() method. + +The startupinfo and creationflags, if given, will be passed to the +underlying CreateProcess() function. They can specify things such as +appearance of the main window and priority for the new process. +(Windows only) + + +This module also defines some shortcut functions: + +call(*popenargs, **kwargs): + Run command with arguments. Wait for command to complete, then + return the returncode attribute. + + The arguments are the same as for the Popen constructor. Example: + + retcode = call(["ls", "-l"]) + +check_call(*popenargs, **kwargs): + Run command with arguments. Wait for command to complete. If the + exit code was zero then return, otherwise raise + CalledProcessError. The CalledProcessError object will have the + return code in the returncode attribute. + + The arguments are the same as for the Popen constructor. Example: + + check_call(["ls", "-l"]) + +check_output(*popenargs, **kwargs): + Run command with arguments and return its output as a byte string. + + If the exit code was non-zero it raises a CalledProcessError. The + CalledProcessError object will have the return code in the returncode + attribute and output in the output attribute. + + The arguments are the same as for the Popen constructor. Example: + + output = check_output(["ls", "-l", "/dev/null"]) + + +Exceptions +---------- +Exceptions raised in the child process, before the new program has +started to execute, will be re-raised in the parent. Additionally, +the exception object will have one extra attribute called +'child_traceback', which is a string containing traceback information +from the childs point of view. + +The most common exception raised is OSError. This occurs, for +example, when trying to execute a non-existent file. Applications +should prepare for OSErrors. + +A ValueError will be raised if Popen is called with invalid arguments. + +check_call() and check_output() will raise CalledProcessError, if the +called process returns a non-zero return code. + + +Security +-------- +Unlike some other popen functions, this implementation will never call +/bin/sh implicitly. This means that all characters, including shell +metacharacters, can safely be passed to child processes. + + +Popen objects +============= +Instances of the Popen class have the following methods: + +poll() + Check if child process has terminated. Returns returncode + attribute. + +wait() + Wait for child process to terminate. Returns returncode attribute. + +communicate(input=None) + Interact with process: Send data to stdin. Read data from stdout + and stderr, until end-of-file is reached. Wait for process to + terminate. The optional input argument should be a string to be + sent to the child process, or None, if no data should be sent to + the child. + + communicate() returns a tuple (stdout, stderr). + + Note: The data read is buffered in memory, so do not use this + method if the data size is large or unlimited. + +The following attributes are also available: + +stdin + If the stdin argument is PIPE, this attribute is a file object + that provides input to the child process. Otherwise, it is None. + +stdout + If the stdout argument is PIPE, this attribute is a file object + that provides output from the child process. Otherwise, it is + None. + +stderr + If the stderr argument is PIPE, this attribute is file object that + provides error output from the child process. Otherwise, it is + None. + +pid + The process ID of the child process. + +returncode + The child return code. A None value indicates that the process + hasn't terminated yet. A negative value -N indicates that the + child was terminated by signal N (UNIX only). + + +Replacing older functions with the subprocess module +==================================================== +In this section, "a ==> b" means that b can be used as a replacement +for a. + +Note: All functions in this section fail (more or less) silently if +the executed program cannot be found; this module raises an OSError +exception. + +In the following examples, we assume that the subprocess module is +imported with "from subprocess import *". + + +Replacing /bin/sh shell backquote +--------------------------------- +output=`mycmd myarg` +==> +output = Popen(["mycmd", "myarg"], stdout=PIPE).communicate()[0] + + +Replacing shell pipe line +------------------------- +output=`dmesg | grep hda` +==> +p1 = Popen(["dmesg"], stdout=PIPE) +p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE) +output = p2.communicate()[0] + + +Replacing os.system() +--------------------- +sts = os.system("mycmd" + " myarg") +==> +p = Popen("mycmd" + " myarg", shell=True) +pid, sts = os.waitpid(p.pid, 0) + +Note: + +* Calling the program through the shell is usually not required. + +* It's easier to look at the returncode attribute than the + exitstatus. + +A more real-world example would look like this: + +try: + retcode = call("mycmd" + " myarg", shell=True) + if retcode < 0: + print >>sys.stderr, "Child was terminated by signal", -retcode + else: + print >>sys.stderr, "Child returned", retcode +except OSError, e: + print >>sys.stderr, "Execution failed:", e + + +Replacing os.spawn* +------------------- +P_NOWAIT example: + +pid = os.spawnlp(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg") +==> +pid = Popen(["/bin/mycmd", "myarg"]).pid + + +P_WAIT example: + +retcode = os.spawnlp(os.P_WAIT, "/bin/mycmd", "mycmd", "myarg") +==> +retcode = call(["/bin/mycmd", "myarg"]) + + +Vector example: + +os.spawnvp(os.P_NOWAIT, path, args) +==> +Popen([path] + args[1:]) + + +Environment example: + +os.spawnlpe(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg", env) +==> +Popen(["/bin/mycmd", "myarg"], env={"PATH": "/usr/bin"}) + + +Replacing os.popen* +------------------- +pipe = os.popen("cmd", mode='r', bufsize) +==> +pipe = Popen("cmd", shell=True, bufsize=bufsize, stdout=PIPE).stdout + +pipe = os.popen("cmd", mode='w', bufsize) +==> +pipe = Popen("cmd", shell=True, bufsize=bufsize, stdin=PIPE).stdin + + +(child_stdin, child_stdout) = os.popen2("cmd", mode, bufsize) +==> +p = Popen("cmd", shell=True, bufsize=bufsize, + stdin=PIPE, stdout=PIPE, close_fds=True) +(child_stdin, child_stdout) = (p.stdin, p.stdout) + + +(child_stdin, + child_stdout, + child_stderr) = os.popen3("cmd", mode, bufsize) +==> +p = Popen("cmd", shell=True, bufsize=bufsize, + stdin=PIPE, stdout=PIPE, stderr=PIPE, close_fds=True) +(child_stdin, + child_stdout, + child_stderr) = (p.stdin, p.stdout, p.stderr) + + +(child_stdin, child_stdout_and_stderr) = os.popen4("cmd", mode, + bufsize) +==> +p = Popen("cmd", shell=True, bufsize=bufsize, + stdin=PIPE, stdout=PIPE, stderr=STDOUT, close_fds=True) +(child_stdin, child_stdout_and_stderr) = (p.stdin, p.stdout) + +On Unix, os.popen2, os.popen3 and os.popen4 also accept a sequence as +the command to execute, in which case arguments will be passed +directly to the program without shell intervention. This usage can be +replaced as follows: + +(child_stdin, child_stdout) = os.popen2(["/bin/ls", "-l"], mode, + bufsize) +==> +p = Popen(["/bin/ls", "-l"], bufsize=bufsize, stdin=PIPE, stdout=PIPE) +(child_stdin, child_stdout) = (p.stdin, p.stdout) + +Return code handling translates as follows: + +pipe = os.popen("cmd", 'w') +... +rc = pipe.close() +if rc is not None and rc % 256: + print "There were some errors" +==> +process = Popen("cmd", 'w', shell=True, stdin=PIPE) +... +process.stdin.close() +if process.wait() != 0: + print "There were some errors" + + +Replacing popen2.* +------------------ +(child_stdout, child_stdin) = popen2.popen2("somestring", bufsize, mode) +==> +p = Popen(["somestring"], shell=True, bufsize=bufsize + stdin=PIPE, stdout=PIPE, close_fds=True) +(child_stdout, child_stdin) = (p.stdout, p.stdin) + +On Unix, popen2 also accepts a sequence as the command to execute, in +which case arguments will be passed directly to the program without +shell intervention. This usage can be replaced as follows: + +(child_stdout, child_stdin) = popen2.popen2(["mycmd", "myarg"], bufsize, + mode) +==> +p = Popen(["mycmd", "myarg"], bufsize=bufsize, + stdin=PIPE, stdout=PIPE, close_fds=True) +(child_stdout, child_stdin) = (p.stdout, p.stdin) + +The popen2.Popen3 and popen2.Popen4 basically works as subprocess.Popen, +except that: + +* subprocess.Popen raises an exception if the execution fails +* the capturestderr argument is replaced with the stderr argument. +* stdin=PIPE and stdout=PIPE must be specified. +* popen2 closes all filedescriptors by default, but you have to specify + close_fds=True with subprocess.Popen. +""" + +import sys +mswindows = (sys.platform == "win32") + +import os +import types +import traceback +import gc +import signal + +# Exception classes used by this module. +class CalledProcessError(Exception): + """This exception is raised when a process run by check_call() or + check_output() returns a non-zero exit status. + The exit status will be stored in the returncode attribute; + check_output() will also store the output in the output attribute. + """ + def __init__(self, returncode, cmd, output=None): + self.returncode = returncode + self.cmd = cmd + self.output = output + def __str__(self): + return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode) + + +if mswindows: + import threading + import msvcrt + import _subprocess + class STARTUPINFO: + dwFlags = 0 + hStdInput = None + hStdOutput = None + hStdError = None + wShowWindow = 0 + class pywintypes: + error = IOError +else: + import select + _has_poll = hasattr(select, 'poll') + import errno + import fcntl + import pickle + + # When select or poll has indicated that the file is writable, + # we can write up to _PIPE_BUF bytes without risk of blocking. + # POSIX defines PIPE_BUF as >= 512. + _PIPE_BUF = getattr(select, 'PIPE_BUF', 512) + + +__all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call", + "check_output", "CalledProcessError"] + +if mswindows: + from _subprocess import CREATE_NEW_CONSOLE, CREATE_NEW_PROCESS_GROUP + __all__.extend(["CREATE_NEW_CONSOLE", "CREATE_NEW_PROCESS_GROUP"]) +try: + MAXFD = os.sysconf("SC_OPEN_MAX") +except: + MAXFD = 256 + +_active = [] + +def _cleanup(): + for inst in _active[:]: + res = inst._internal_poll(_deadstate=sys.maxint) + if res is not None and res >= 0: + try: + _active.remove(inst) + except ValueError: + # This can happen if two threads create a new Popen instance. + # It's harmless that it was already removed, so ignore. + pass + +PIPE = -1 +STDOUT = -2 + + +def _eintr_retry_call(func, *args): + while True: + try: + return func(*args) + except OSError, e: + if e.errno == errno.EINTR: + continue + raise + + +def call(*popenargs, **kwargs): + """Run command with arguments. Wait for command to complete, then + return the returncode attribute. + + The arguments are the same as for the Popen constructor. Example: + + retcode = call(["ls", "-l"]) + """ + return Popen(*popenargs, **kwargs).wait() + + +def check_call(*popenargs, **kwargs): + """Run command with arguments. Wait for command to complete. If + the exit code was zero then return, otherwise raise + CalledProcessError. The CalledProcessError object will have the + return code in the returncode attribute. + + The arguments are the same as for the Popen constructor. Example: + + check_call(["ls", "-l"]) + """ + retcode = call(*popenargs, **kwargs) + if retcode: + cmd = kwargs.get("args") + if cmd is None: + cmd = popenargs[0] + raise CalledProcessError(retcode, cmd) + return 0 + + +def check_output(*popenargs, **kwargs): + r"""Run command with arguments and return its output as a byte string. + + If the exit code was non-zero it raises a CalledProcessError. The + CalledProcessError object will have the return code in the returncode + attribute and output in the output attribute. + + The arguments are the same as for the Popen constructor. Example: + + >>> check_output(["ls", "-l", "/dev/null"]) + 'crw-rw-rw- 1 root root 1, 3 Oct 18 2007 /dev/null\n' + + The stdout argument is not allowed as it is used internally. + To capture standard error in the result, use stderr=STDOUT. + + >>> check_output(["/bin/sh", "-c", + ... "ls -l non_existent_file ; exit 0"], + ... stderr=STDOUT) + 'ls: non_existent_file: No such file or directory\n' + """ + if 'stdout' in kwargs: + raise ValueError('stdout argument not allowed, it will be overridden.') + process = Popen(stdout=PIPE, *popenargs, **kwargs) + output, unused_err = process.communicate() + retcode = process.poll() + if retcode: + cmd = kwargs.get("args") + if cmd is None: + cmd = popenargs[0] + raise CalledProcessError(retcode, cmd, output=output) + return output + + +def list2cmdline(seq): + """ + Translate a sequence of arguments into a command line + string, using the same rules as the MS C runtime: + + 1) Arguments are delimited by white space, which is either a + space or a tab. + + 2) A string surrounded by double quotation marks is + interpreted as a single argument, regardless of white space + contained within. A quoted string can be embedded in an + argument. + + 3) A double quotation mark preceded by a backslash is + interpreted as a literal double quotation mark. + + 4) Backslashes are interpreted literally, unless they + immediately precede a double quotation mark. + + 5) If backslashes immediately precede a double quotation mark, + every pair of backslashes is interpreted as a literal + backslash. If the number of backslashes is odd, the last + backslash escapes the next double quotation mark as + described in rule 3. + """ + + # See + # http://msdn.microsoft.com/en-us/library/17w5ykft.aspx + # or search http://msdn.microsoft.com for + # "Parsing C++ Command-Line Arguments" + result = [] + needquote = False + for arg in seq: + bs_buf = [] + + # Add a space to separate this argument from the others + if result: + result.append(' ') + + needquote = (" " in arg) or ("\t" in arg) or not arg + if needquote: + result.append('"') + + for c in arg: + if c == '\\': + # Don't know if we need to double yet. + bs_buf.append(c) + elif c == '"': + # Double backslashes. + result.append('\\' * len(bs_buf)*2) + bs_buf = [] + result.append('\\"') + else: + # Normal char + if bs_buf: + result.extend(bs_buf) + bs_buf = [] + result.append(c) + + # Add remaining backslashes, if any. + if bs_buf: + result.extend(bs_buf) + + if needquote: + result.extend(bs_buf) + result.append('"') + + return ''.join(result) + + +class Popen(object): + def __init__(self, args, bufsize=0, executable=None, + stdin=None, stdout=None, stderr=None, + preexec_fn=None, close_fds=False, shell=False, + cwd=None, env=None, universal_newlines=False, + startupinfo=None, creationflags=0): + """Create new Popen instance.""" + _cleanup() + + self._child_created = False + if not isinstance(bufsize, (int, long)): + raise TypeError("bufsize must be an integer") + + if mswindows: + if preexec_fn is not None: + raise ValueError("preexec_fn is not supported on Windows " + "platforms") + if close_fds and (stdin is not None or stdout is not None or + stderr is not None): + raise ValueError("close_fds is not supported on Windows " + "platforms if you redirect stdin/stdout/stderr") + else: + # POSIX + if startupinfo is not None: + raise ValueError("startupinfo is only supported on Windows " + "platforms") + if creationflags != 0: + raise ValueError("creationflags is only supported on Windows " + "platforms") + + self.stdin = None + self.stdout = None + self.stderr = None + self.pid = None + self.returncode = None + self.universal_newlines = universal_newlines + + # Input and output objects. The general principle is like + # this: + # + # Parent Child + # ------ ----- + # p2cwrite ---stdin---> p2cread + # c2pread <--stdout--- c2pwrite + # errread <--stderr--- errwrite + # + # On POSIX, the child objects are file descriptors. On + # Windows, these are Windows file handles. The parent objects + # are file descriptors on both platforms. The parent objects + # are None when not using PIPEs. The child objects are None + # when not redirecting. + + (p2cread, p2cwrite, + c2pread, c2pwrite, + errread, errwrite) = self._get_handles(stdin, stdout, stderr) + + self._execute_child(args, executable, preexec_fn, close_fds, + cwd, env, universal_newlines, + startupinfo, creationflags, shell, + p2cread, p2cwrite, + c2pread, c2pwrite, + errread, errwrite) + + if mswindows: + if p2cwrite is not None: + p2cwrite = msvcrt.open_osfhandle(p2cwrite.Detach(), 0) + if c2pread is not None: + c2pread = msvcrt.open_osfhandle(c2pread.Detach(), 0) + if errread is not None: + errread = msvcrt.open_osfhandle(errread.Detach(), 0) + + if p2cwrite is not None: + self.stdin = os.fdopen(p2cwrite, 'wb', bufsize) + if c2pread is not None: + if universal_newlines: + self.stdout = os.fdopen(c2pread, 'rU', bufsize) + else: + self.stdout = os.fdopen(c2pread, 'rb', bufsize) + if errread is not None: + if universal_newlines: + self.stderr = os.fdopen(errread, 'rU', bufsize) + else: + self.stderr = os.fdopen(errread, 'rb', bufsize) + + + def _translate_newlines(self, data): + data = data.replace("\r\n", "\n") + data = data.replace("\r", "\n") + return data + + + def __del__(self, _maxint=sys.maxint, _active=_active): + if not self._child_created: + # We didn't get to successfully create a child process. + return + # In case the child hasn't been waited on, check if it's done. + self._internal_poll(_deadstate=_maxint) + if self.returncode is None and _active is not None: + # Child is still running, keep us alive until we can wait on it. + _active.append(self) + + + def communicate(self, input=None): + """Interact with process: Send data to stdin. Read data from + stdout and stderr, until end-of-file is reached. Wait for + process to terminate. The optional input argument should be a + string to be sent to the child process, or None, if no data + should be sent to the child. + + communicate() returns a tuple (stdout, stderr).""" + + # Optimization: If we are only using one pipe, or no pipe at + # all, using select() or threads is unnecessary. + if [self.stdin, self.stdout, self.stderr].count(None) >= 2: + stdout = None + stderr = None + if self.stdin: + if input: + self.stdin.write(input) + self.stdin.close() + elif self.stdout: + stdout = self.stdout.read() + self.stdout.close() + elif self.stderr: + stderr = self.stderr.read() + self.stderr.close() + self.wait() + return (stdout, stderr) + + return self._communicate(input) + + + def poll(self): + return self._internal_poll() + + + if mswindows: + # + # Windows methods + # + def _get_handles(self, stdin, stdout, stderr): + """Construct and return tuple with IO objects: + p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite + """ + if stdin is None and stdout is None and stderr is None: + return (None, None, None, None, None, None) + + p2cread, p2cwrite = None, None + c2pread, c2pwrite = None, None + errread, errwrite = None, None + + if stdin is None: + p2cread = _subprocess.GetStdHandle(_subprocess.STD_INPUT_HANDLE) + if p2cread is None: + p2cread, _ = _subprocess.CreatePipe(None, 0) + elif stdin == PIPE: + p2cread, p2cwrite = _subprocess.CreatePipe(None, 0) + elif isinstance(stdin, int): + p2cread = msvcrt.get_osfhandle(stdin) + else: + # Assuming file-like object + p2cread = msvcrt.get_osfhandle(stdin.fileno()) + p2cread = self._make_inheritable(p2cread) + + if stdout is None: + c2pwrite = _subprocess.GetStdHandle(_subprocess.STD_OUTPUT_HANDLE) + if c2pwrite is None: + _, c2pwrite = _subprocess.CreatePipe(None, 0) + elif stdout == PIPE: + c2pread, c2pwrite = _subprocess.CreatePipe(None, 0) + elif isinstance(stdout, int): + c2pwrite = msvcrt.get_osfhandle(stdout) + else: + # Assuming file-like object + c2pwrite = msvcrt.get_osfhandle(stdout.fileno()) + c2pwrite = self._make_inheritable(c2pwrite) + + if stderr is None: + errwrite = _subprocess.GetStdHandle(_subprocess.STD_ERROR_HANDLE) + if errwrite is None: + _, errwrite = _subprocess.CreatePipe(None, 0) + elif stderr == PIPE: + errread, errwrite = _subprocess.CreatePipe(None, 0) + elif stderr == STDOUT: + errwrite = c2pwrite + elif isinstance(stderr, int): + errwrite = msvcrt.get_osfhandle(stderr) + else: + # Assuming file-like object + errwrite = msvcrt.get_osfhandle(stderr.fileno()) + errwrite = self._make_inheritable(errwrite) + + return (p2cread, p2cwrite, + c2pread, c2pwrite, + errread, errwrite) + + + def _make_inheritable(self, handle): + """Return a duplicate of handle, which is inheritable""" + return _subprocess.DuplicateHandle(_subprocess.GetCurrentProcess(), + handle, _subprocess.GetCurrentProcess(), 0, 1, + _subprocess.DUPLICATE_SAME_ACCESS) + + + def _find_w9xpopen(self): + """Find and return absolut path to w9xpopen.exe""" + w9xpopen = os.path.join( + os.path.dirname(_subprocess.GetModuleFileName(0)), + "w9xpopen.exe") + if not os.path.exists(w9xpopen): + # Eeek - file-not-found - possibly an embedding + # situation - see if we can locate it in sys.exec_prefix + w9xpopen = os.path.join(os.path.dirname(sys.exec_prefix), + "w9xpopen.exe") + if not os.path.exists(w9xpopen): + raise RuntimeError("Cannot locate w9xpopen.exe, which is " + "needed for Popen to work with your " + "shell or platform.") + return w9xpopen + + + def _execute_child(self, args, executable, preexec_fn, close_fds, + cwd, env, universal_newlines, + startupinfo, creationflags, shell, + p2cread, p2cwrite, + c2pread, c2pwrite, + errread, errwrite): + """Execute program (MS Windows version)""" + + if not isinstance(args, types.StringTypes): + args = list2cmdline(args) + + # Process startup details + if startupinfo is None: + startupinfo = STARTUPINFO() + if None not in (p2cread, c2pwrite, errwrite): + startupinfo.dwFlags |= _subprocess.STARTF_USESTDHANDLES + startupinfo.hStdInput = p2cread + startupinfo.hStdOutput = c2pwrite + startupinfo.hStdError = errwrite + + if shell: + startupinfo.dwFlags |= _subprocess.STARTF_USESHOWWINDOW + startupinfo.wShowWindow = _subprocess.SW_HIDE + comspec = os.environ.get("COMSPEC", "cmd.exe") + args = '{} /c "{}"'.format (comspec, args) + if (_subprocess.GetVersion() >= 0x80000000 or + os.path.basename(comspec).lower() == "command.com"): + # Win9x, or using command.com on NT. We need to + # use the w9xpopen intermediate program. For more + # information, see KB Q150956 + # (http://web.archive.org/web/20011105084002/http://support.microsoft.com/support/kb/articles/Q150/9/56.asp) + w9xpopen = self._find_w9xpopen() + args = '"%s" %s' % (w9xpopen, args) + # Not passing CREATE_NEW_CONSOLE has been known to + # cause random failures on win9x. Specifically a + # dialog: "Your program accessed mem currently in + # use at xxx" and a hopeful warning about the + # stability of your system. Cost is Ctrl+C wont + # kill children. + creationflags |= _subprocess.CREATE_NEW_CONSOLE + + # Start the process + try: + hp, ht, pid, tid = _subprocess.CreateProcess(executable, args, + # no special security + None, None, + int(not close_fds), + creationflags, + env, + cwd, + startupinfo) + except pywintypes.error, e: + # Translate pywintypes.error to WindowsError, which is + # a subclass of OSError. FIXME: We should really + # translate errno using _sys_errlist (or simliar), but + # how can this be done from Python? + raise WindowsError(*e.args) + finally: + # Child is launched. Close the parent's copy of those pipe + # handles that only the child should have open. You need + # to make sure that no handles to the write end of the + # output pipe are maintained in this process or else the + # pipe will not close when the child process exits and the + # ReadFile will hang. + if p2cread is not None: + p2cread.Close() + if c2pwrite is not None: + c2pwrite.Close() + if errwrite is not None: + errwrite.Close() + + # Retain the process handle, but close the thread handle + self._child_created = True + self._handle = hp + self.pid = pid + ht.Close() + + def _internal_poll(self, _deadstate=None, + _WaitForSingleObject=_subprocess.WaitForSingleObject, + _WAIT_OBJECT_0=_subprocess.WAIT_OBJECT_0, + _GetExitCodeProcess=_subprocess.GetExitCodeProcess): + """Check if child process has terminated. Returns returncode + attribute. + + This method is called by __del__, so it can only refer to objects + in its local scope. + + """ + if self.returncode is None: + if _WaitForSingleObject(self._handle, 0) == _WAIT_OBJECT_0: + self.returncode = _GetExitCodeProcess(self._handle) + return self.returncode + + + def wait(self): + """Wait for child process to terminate. Returns returncode + attribute.""" + if self.returncode is None: + _subprocess.WaitForSingleObject(self._handle, + _subprocess.INFINITE) + self.returncode = _subprocess.GetExitCodeProcess(self._handle) + return self.returncode + + + def _readerthread(self, fh, buffer): + buffer.append(fh.read()) + + + def _communicate(self, input): + stdout = None # Return + stderr = None # Return + + if self.stdout: + stdout = [] + stdout_thread = threading.Thread(target=self._readerthread, + args=(self.stdout, stdout)) + stdout_thread.setDaemon(True) + stdout_thread.start() + if self.stderr: + stderr = [] + stderr_thread = threading.Thread(target=self._readerthread, + args=(self.stderr, stderr)) + stderr_thread.setDaemon(True) + stderr_thread.start() + + if self.stdin: + if input is not None: + self.stdin.write(input) + self.stdin.close() + + if self.stdout: + stdout_thread.join() + if self.stderr: + stderr_thread.join() + + # All data exchanged. Translate lists into strings. + if stdout is not None: + stdout = stdout[0] + if stderr is not None: + stderr = stderr[0] + + # Translate newlines, if requested. We cannot let the file + # object do the translation: It is based on stdio, which is + # impossible to combine with select (unless forcing no + # buffering). + if self.universal_newlines and hasattr(file, 'newlines'): + if stdout: + stdout = self._translate_newlines(stdout) + if stderr: + stderr = self._translate_newlines(stderr) + + self.wait() + return (stdout, stderr) + + def send_signal(self, sig): + """Send a signal to the process + """ + if sig == signal.SIGTERM: + self.terminate() + elif sig == signal.CTRL_C_EVENT: + os.kill(self.pid, signal.CTRL_C_EVENT) + elif sig == signal.CTRL_BREAK_EVENT: + os.kill(self.pid, signal.CTRL_BREAK_EVENT) + else: + raise ValueError("Unsupported signal: {}".format(sig)) + + def terminate(self): + """Terminates the process + """ + _subprocess.TerminateProcess(self._handle, 1) + + kill = terminate + + else: + # + # POSIX methods + # + def _get_handles(self, stdin, stdout, stderr): + """Construct and return tuple with IO objects: + p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite + """ + p2cread, p2cwrite = None, None + c2pread, c2pwrite = None, None + errread, errwrite = None, None + + if stdin is None: + pass + elif stdin == PIPE: + p2cread, p2cwrite = os.pipe() + elif isinstance(stdin, int): + p2cread = stdin + else: + # Assuming file-like object + p2cread = stdin.fileno() + + if stdout is None: + pass + elif stdout == PIPE: + c2pread, c2pwrite = os.pipe() + elif isinstance(stdout, int): + c2pwrite = stdout + else: + # Assuming file-like object + c2pwrite = stdout.fileno() + + if stderr is None: + pass + elif stderr == PIPE: + errread, errwrite = os.pipe() + elif stderr == STDOUT: + errwrite = c2pwrite + elif isinstance(stderr, int): + errwrite = stderr + else: + # Assuming file-like object + errwrite = stderr.fileno() + + return (p2cread, p2cwrite, + c2pread, c2pwrite, + errread, errwrite) + + + def _set_cloexec_flag(self, fd): + try: + cloexec_flag = fcntl.FD_CLOEXEC + except AttributeError: + cloexec_flag = 1 + + old = fcntl.fcntl(fd, fcntl.F_GETFD) + fcntl.fcntl(fd, fcntl.F_SETFD, old | cloexec_flag) + + + def _close_fds(self, but): + if hasattr(os, 'closerange'): + os.closerange(3, but) + os.closerange(but + 1, MAXFD) + else: + for i in xrange(3, MAXFD): + if i == but: + continue + try: + os.close(i) + except: + pass + + + def _execute_child(self, args, executable, preexec_fn, close_fds, + cwd, env, universal_newlines, + startupinfo, creationflags, shell, + p2cread, p2cwrite, + c2pread, c2pwrite, + errread, errwrite): + """Execute program (POSIX version)""" + + if isinstance(args, types.StringTypes): + args = [args] + else: + args = list(args) + + if shell: + args = ["/bin/sh", "-c"] + args + if executable: + args[0] = executable + + if executable is None: + executable = args[0] + + # For transferring possible exec failure from child to parent + # The first char specifies the exception type: 0 means + # OSError, 1 means some other error. + errpipe_read, errpipe_write = os.pipe() + try: + try: + self._set_cloexec_flag(errpipe_write) + + gc_was_enabled = gc.isenabled() + # Disable gc to avoid bug where gc -> file_dealloc -> + # write to stderr -> hang. http://bugs.python.org/issue1336 + gc.disable() + try: + self.pid = os.fork() + except: + if gc_was_enabled: + gc.enable() + raise + self._child_created = True + if self.pid == 0: + # Child + try: + # Close parent's pipe ends + if p2cwrite is not None: + os.close(p2cwrite) + if c2pread is not None: + os.close(c2pread) + if errread is not None: + os.close(errread) + os.close(errpipe_read) + + # Dup fds for child + if p2cread is not None: + os.dup2(p2cread, 0) + if c2pwrite is not None: + os.dup2(c2pwrite, 1) + if errwrite is not None: + os.dup2(errwrite, 2) + + # Close pipe fds. Make sure we don't close the same + # fd more than once, or standard fds. + if p2cread is not None and p2cread not in (0,): + os.close(p2cread) + if c2pwrite is not None and c2pwrite not in (p2cread, 1): + os.close(c2pwrite) + if errwrite is not None and errwrite not in (p2cread, c2pwrite, 2): + os.close(errwrite) + + # Close all other fds, if asked for + if close_fds: + self._close_fds(but=errpipe_write) + + if cwd is not None: + os.chdir(cwd) + + if preexec_fn: + preexec_fn() + + if env is None: + os.execvp(executable, args) + else: + os.execvpe(executable, args, env) + + except: + exc_type, exc_value, tb = sys.exc_info() + # Save the traceback and attach it to the exception object + exc_lines = traceback.format_exception(exc_type, + exc_value, + tb) + exc_value.child_traceback = ''.join(exc_lines) + os.write(errpipe_write, pickle.dumps(exc_value)) + + # This exitcode won't be reported to applications, so it + # really doesn't matter what we return. + os._exit(255) + + # Parent + if gc_was_enabled: + gc.enable() + finally: + # be sure the FD is closed no matter what + os.close(errpipe_write) + + if p2cread is not None and p2cwrite is not None: + os.close(p2cread) + if c2pwrite is not None and c2pread is not None: + os.close(c2pwrite) + if errwrite is not None and errread is not None: + os.close(errwrite) + + # Wait for exec to fail or succeed; possibly raising exception + # Exception limited to 1M + data = _eintr_retry_call(os.read, errpipe_read, 1048576) + finally: + # be sure the FD is closed no matter what + os.close(errpipe_read) + + if data != "": + _eintr_retry_call(os.waitpid, self.pid, 0) + child_exception = pickle.loads(data) + for fd in (p2cwrite, c2pread, errread): + if fd is not None: + os.close(fd) + raise child_exception + + + def _handle_exitstatus(self, sts, _WIFSIGNALED=os.WIFSIGNALED, + _WTERMSIG=os.WTERMSIG, _WIFEXITED=os.WIFEXITED, + _WEXITSTATUS=os.WEXITSTATUS): + # This method is called (indirectly) by __del__, so it cannot + # refer to anything outside of its local scope.""" + if _WIFSIGNALED(sts): + self.returncode = -_WTERMSIG(sts) + elif _WIFEXITED(sts): + self.returncode = _WEXITSTATUS(sts) + else: + # Should never happen + raise RuntimeError("Unknown child exit status!") + + + def _internal_poll(self, _deadstate=None, _waitpid=os.waitpid, + _WNOHANG=os.WNOHANG, _os_error=os.error): + """Check if child process has terminated. Returns returncode + attribute. + + This method is called by __del__, so it cannot reference anything + outside of the local scope (nor can any methods it calls). + + """ + if self.returncode is None: + try: + pid, sts = _waitpid(self.pid, _WNOHANG) + if pid == self.pid: + self._handle_exitstatus(sts) + except _os_error: + if _deadstate is not None: + self.returncode = _deadstate + return self.returncode + + + def wait(self): + """Wait for child process to terminate. Returns returncode + attribute.""" + if self.returncode is None: + pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0) + self._handle_exitstatus(sts) + return self.returncode + + + def _communicate(self, input): + if self.stdin: + # Flush stdio buffer. This might block, if the user has + # been writing to .stdin in an uncontrolled fashion. + self.stdin.flush() + if not input: + self.stdin.close() + + if _has_poll: + stdout, stderr = self._communicate_with_poll(input) + else: + stdout, stderr = self._communicate_with_select(input) + + # All data exchanged. Translate lists into strings. + if stdout is not None: + stdout = ''.join(stdout) + if stderr is not None: + stderr = ''.join(stderr) + + # Translate newlines, if requested. We cannot let the file + # object do the translation: It is based on stdio, which is + # impossible to combine with select (unless forcing no + # buffering). + if self.universal_newlines and hasattr(file, 'newlines'): + if stdout: + stdout = self._translate_newlines(stdout) + if stderr: + stderr = self._translate_newlines(stderr) + + self.wait() + return (stdout, stderr) + + + def _communicate_with_poll(self, input): + stdout = None # Return + stderr = None # Return + fd2file = {} + fd2output = {} + + poller = select.poll() + def register_and_append(file_obj, eventmask): + poller.register(file_obj.fileno(), eventmask) + fd2file[file_obj.fileno()] = file_obj + + def close_unregister_and_remove(fd): + poller.unregister(fd) + fd2file[fd].close() + fd2file.pop(fd) + + if self.stdin and input: + register_and_append(self.stdin, select.POLLOUT) + + select_POLLIN_POLLPRI = select.POLLIN | select.POLLPRI + if self.stdout: + register_and_append(self.stdout, select_POLLIN_POLLPRI) + fd2output[self.stdout.fileno()] = stdout = [] + if self.stderr: + register_and_append(self.stderr, select_POLLIN_POLLPRI) + fd2output[self.stderr.fileno()] = stderr = [] + + input_offset = 0 + while fd2file: + try: + ready = poller.poll() + except select.error, e: + if e.args[0] == errno.EINTR: + continue + raise + + for fd, mode in ready: + if mode & select.POLLOUT: + chunk = input[input_offset : input_offset + _PIPE_BUF] + input_offset += os.write(fd, chunk) + if input_offset >= len(input): + close_unregister_and_remove(fd) + elif mode & select_POLLIN_POLLPRI: + data = os.read(fd, 4096) + if not data: + close_unregister_and_remove(fd) + fd2output[fd].append(data) + else: + # Ignore hang up or errors. + close_unregister_and_remove(fd) + + return (stdout, stderr) + + + def _communicate_with_select(self, input): + read_set = [] + write_set = [] + stdout = None # Return + stderr = None # Return + + if self.stdin and input: + write_set.append(self.stdin) + if self.stdout: + read_set.append(self.stdout) + stdout = [] + if self.stderr: + read_set.append(self.stderr) + stderr = [] + + input_offset = 0 + while read_set or write_set: + try: + rlist, wlist, xlist = select.select(read_set, write_set, []) + except select.error, e: + if e.args[0] == errno.EINTR: + continue + raise + + if self.stdin in wlist: + chunk = input[input_offset : input_offset + _PIPE_BUF] + bytes_written = os.write(self.stdin.fileno(), chunk) + input_offset += bytes_written + if input_offset >= len(input): + self.stdin.close() + write_set.remove(self.stdin) + + if self.stdout in rlist: + data = os.read(self.stdout.fileno(), 1024) + if data == "": + self.stdout.close() + read_set.remove(self.stdout) + stdout.append(data) + + if self.stderr in rlist: + data = os.read(self.stderr.fileno(), 1024) + if data == "": + self.stderr.close() + read_set.remove(self.stderr) + stderr.append(data) + + return (stdout, stderr) + + + def send_signal(self, sig): + """Send a signal to the process + """ + os.kill(self.pid, sig) + + def terminate(self): + """Terminate the process with SIGTERM + """ + self.send_signal(signal.SIGTERM) + + def kill(self): + """Kill the process with SIGKILL + """ + self.send_signal(signal.SIGKILL) + + +def _demo_posix(): + # + # Example 1: Simple redirection: Get process list + # + plist = Popen(["ps"], stdout=PIPE).communicate()[0] + print "Process list:" + print plist + + # + # Example 2: Change uid before executing child + # + if os.getuid() == 0: + p = Popen(["id"], preexec_fn=lambda: os.setuid(100)) + p.wait() + + # + # Example 3: Connecting several subprocesses + # + print "Looking for 'hda'..." + p1 = Popen(["dmesg"], stdout=PIPE) + p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE) + print repr(p2.communicate()[0]) + + # + # Example 4: Catch execution error + # + print + print "Trying a weird file..." + try: + print Popen(["/this/path/does/not/exist"]).communicate() + except OSError, e: + if e.errno == errno.ENOENT: + print "The file didn't exist. I thought so..." + print "Child traceback:" + print e.child_traceback + else: + print "Error", e.errno + else: + print >>sys.stderr, "Gosh. No error." + + +def _demo_windows(): + # + # Example 1: Connecting several subprocesses + # + print "Looking for 'PROMPT' in set output..." + p1 = Popen("set", stdout=PIPE, shell=True) + p2 = Popen('find "PROMPT"', stdin=p1.stdout, stdout=PIPE) + print repr(p2.communicate()[0]) + + # + # Example 2: Simple execution of program + # + print "Executing calc..." + p = Popen("calc") + p.wait() + + +if __name__ == "__main__": + if mswindows: + _demo_windows() + else: + _demo_posix() |