1249 lines
43 KiB
Python
1249 lines
43 KiB
Python
# subprocess - Subprocesses with accessible I/O streams
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#
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# For more information about this module, see PEP 324.
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#
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# This module should remain compatible with Python 2.2, see PEP 291.
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#
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# Copyright (c) 2003-2005 by Peter Astrand <astrand@lysator.liu.se>
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#
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# Licensed to PSF under a Contributor Agreement.
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# See http://www.python.org/2.4/license for licensing details.
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r"""subprocess - Subprocesses with accessible I/O streams
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This module allows you to spawn processes, connect to their
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input/output/error pipes, and obtain their return codes. This module
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intends to replace several other, older modules and functions, like:
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os.system
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os.spawn*
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os.popen*
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popen2.*
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commands.*
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Information about how the subprocess module can be used to replace these
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modules and functions can be found below.
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Using the subprocess module
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===========================
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This module defines one class called Popen:
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class Popen(args, bufsize=0, executable=None,
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stdin=None, stdout=None, stderr=None,
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preexec_fn=None, close_fds=False, shell=False,
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cwd=None, env=None, universal_newlines=False,
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startupinfo=None, creationflags=0):
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Arguments are:
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args should be a string, or a sequence of program arguments. The
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program to execute is normally the first item in the args sequence or
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string, but can be explicitly set by using the executable argument.
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On UNIX, with shell=False (default): In this case, the Popen class
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uses os.execvp() to execute the child program. args should normally
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be a sequence. A string will be treated as a sequence with the string
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as the only item (the program to execute).
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On UNIX, with shell=True: If args is a string, it specifies the
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command string to execute through the shell. If args is a sequence,
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the first item specifies the command string, and any additional items
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will be treated as additional shell arguments.
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On Windows: the Popen class uses CreateProcess() to execute the child
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program, which operates on strings. If args is a sequence, it will be
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converted to a string using the list2cmdline method. Please note that
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not all MS Windows applications interpret the command line the same
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way: The list2cmdline is designed for applications using the same
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rules as the MS C runtime.
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bufsize, if given, has the same meaning as the corresponding argument
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to the built-in open() function: 0 means unbuffered, 1 means line
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buffered, any other positive value means use a buffer of
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(approximately) that size. A negative bufsize means to use the system
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default, which usually means fully buffered. The default value for
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bufsize is 0 (unbuffered).
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stdin, stdout and stderr specify the executed programs' standard
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input, standard output and standard error file handles, respectively.
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Valid values are PIPE, an existing file descriptor (a positive
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integer), an existing file object, and None. PIPE indicates that a
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new pipe to the child should be created. With None, no redirection
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will occur; the child's file handles will be inherited from the
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parent. Additionally, stderr can be STDOUT, which indicates that the
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stderr data from the applications should be captured into the same
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file handle as for stdout.
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If preexec_fn is set to a callable object, this object will be called
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in the child process just before the child is executed.
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If close_fds is true, all file descriptors except 0, 1 and 2 will be
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closed before the child process is executed.
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if shell is true, the specified command will be executed through the
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shell.
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If cwd is not None, the current directory will be changed to cwd
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before the child is executed.
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If env is not None, it defines the environment variables for the new
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process.
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If universal_newlines is true, the file objects stdout and stderr are
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opened as a text files, but lines may be terminated by any of '\n',
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the Unix end-of-line convention, '\r', the Macintosh convention or
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'\r\n', the Windows convention. All of these external representations
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are seen as '\n' by the Python program. Note: This feature is only
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available if Python is built with universal newline support (the
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default). Also, the newlines attribute of the file objects stdout,
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stdin and stderr are not updated by the communicate() method.
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The startupinfo and creationflags, if given, will be passed to the
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underlying CreateProcess() function. They can specify things such as
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appearance of the main window and priority for the new process.
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(Windows only)
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This module also defines two shortcut functions:
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call(*popenargs, **kwargs):
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Run command with arguments. Wait for command to complete, then
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return the returncode attribute.
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The arguments are the same as for the Popen constructor. Example:
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retcode = call(["ls", "-l"])
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check_call(*popenargs, **kwargs):
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Run command with arguments. Wait for command to complete. If the
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exit code was zero then return, otherwise raise
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CalledProcessError. The CalledProcessError object will have the
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return code in the returncode attribute.
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The arguments are the same as for the Popen constructor. Example:
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check_call(["ls", "-l"])
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Exceptions
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----------
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Exceptions raised in the child process, before the new program has
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started to execute, will be re-raised in the parent. Additionally,
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the exception object will have one extra attribute called
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'child_traceback', which is a string containing traceback information
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from the childs point of view.
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The most common exception raised is OSError. This occurs, for
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example, when trying to execute a non-existent file. Applications
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should prepare for OSErrors.
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A ValueError will be raised if Popen is called with invalid arguments.
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check_call() will raise CalledProcessError, if the called process
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returns a non-zero return code.
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Security
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--------
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Unlike some other popen functions, this implementation will never call
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/bin/sh implicitly. This means that all characters, including shell
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metacharacters, can safely be passed to child processes.
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Popen objects
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=============
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Instances of the Popen class have the following methods:
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poll()
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Check if child process has terminated. Returns returncode
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attribute.
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wait()
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Wait for child process to terminate. Returns returncode attribute.
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communicate(input=None)
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Interact with process: Send data to stdin. Read data from stdout
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and stderr, until end-of-file is reached. Wait for process to
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terminate. The optional input argument should be a string to be
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sent to the child process, or None, if no data should be sent to
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the child.
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communicate() returns a tuple (stdout, stderr).
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Note: The data read is buffered in memory, so do not use this
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method if the data size is large or unlimited.
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The following attributes are also available:
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stdin
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If the stdin argument is PIPE, this attribute is a file object
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that provides input to the child process. Otherwise, it is None.
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stdout
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If the stdout argument is PIPE, this attribute is a file object
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that provides output from the child process. Otherwise, it is
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None.
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stderr
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If the stderr argument is PIPE, this attribute is file object that
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provides error output from the child process. Otherwise, it is
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None.
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pid
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The process ID of the child process.
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returncode
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The child return code. A None value indicates that the process
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hasn't terminated yet. A negative value -N indicates that the
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child was terminated by signal N (UNIX only).
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Replacing older functions with the subprocess module
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====================================================
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In this section, "a ==> b" means that b can be used as a replacement
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for a.
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Note: All functions in this section fail (more or less) silently if
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the executed program cannot be found; this module raises an OSError
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exception.
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In the following examples, we assume that the subprocess module is
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imported with "from subprocess import *".
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Replacing /bin/sh shell backquote
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---------------------------------
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output=`mycmd myarg`
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==>
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output = Popen(["mycmd", "myarg"], stdout=PIPE).communicate()[0]
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Replacing shell pipe line
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-------------------------
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output=`dmesg | grep hda`
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==>
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p1 = Popen(["dmesg"], stdout=PIPE)
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p2 = Popen(["grep", "hda"], stdin=p1.stdout, stdout=PIPE)
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output = p2.communicate()[0]
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Replacing os.system()
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---------------------
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sts = os.system("mycmd" + " myarg")
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==>
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p = Popen("mycmd" + " myarg", shell=True)
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pid, sts = os.waitpid(p.pid, 0)
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Note:
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* Calling the program through the shell is usually not required.
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* It's easier to look at the returncode attribute than the
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exitstatus.
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A more real-world example would look like this:
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try:
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retcode = call("mycmd" + " myarg", shell=True)
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if retcode < 0:
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print >>sys.stderr, "Child was terminated by signal", -retcode
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else:
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print >>sys.stderr, "Child returned", retcode
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except OSError, e:
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print >>sys.stderr, "Execution failed:", e
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Replacing os.spawn*
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-------------------
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P_NOWAIT example:
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pid = os.spawnlp(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg")
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==>
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pid = Popen(["/bin/mycmd", "myarg"]).pid
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P_WAIT example:
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retcode = os.spawnlp(os.P_WAIT, "/bin/mycmd", "mycmd", "myarg")
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==>
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retcode = call(["/bin/mycmd", "myarg"])
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Vector example:
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os.spawnvp(os.P_NOWAIT, path, args)
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==>
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Popen([path] + args[1:])
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Environment example:
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os.spawnlpe(os.P_NOWAIT, "/bin/mycmd", "mycmd", "myarg", env)
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==>
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Popen(["/bin/mycmd", "myarg"], env={"PATH": "/usr/bin"})
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Replacing os.popen*
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-------------------
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pipe = os.popen(cmd, mode='r', bufsize)
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==>
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pipe = Popen(cmd, shell=True, bufsize=bufsize, stdout=PIPE).stdout
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pipe = os.popen(cmd, mode='w', bufsize)
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==>
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pipe = Popen(cmd, shell=True, bufsize=bufsize, stdin=PIPE).stdin
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(child_stdin, child_stdout) = os.popen2(cmd, mode, bufsize)
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==>
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p = Popen(cmd, shell=True, bufsize=bufsize,
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stdin=PIPE, stdout=PIPE, close_fds=True)
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(child_stdin, child_stdout) = (p.stdin, p.stdout)
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(child_stdin,
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child_stdout,
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child_stderr) = os.popen3(cmd, mode, bufsize)
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==>
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p = Popen(cmd, shell=True, bufsize=bufsize,
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stdin=PIPE, stdout=PIPE, stderr=PIPE, close_fds=True)
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(child_stdin,
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child_stdout,
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child_stderr) = (p.stdin, p.stdout, p.stderr)
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(child_stdin, child_stdout_and_stderr) = os.popen4(cmd, mode, bufsize)
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==>
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p = Popen(cmd, shell=True, bufsize=bufsize,
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stdin=PIPE, stdout=PIPE, stderr=STDOUT, close_fds=True)
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(child_stdin, child_stdout_and_stderr) = (p.stdin, p.stdout)
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Replacing popen2.*
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------------------
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Note: If the cmd argument to popen2 functions is a string, the command
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is executed through /bin/sh. If it is a list, the command is directly
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executed.
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(child_stdout, child_stdin) = popen2.popen2("somestring", bufsize, mode)
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==>
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p = Popen(["somestring"], shell=True, bufsize=bufsize
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stdin=PIPE, stdout=PIPE, close_fds=True)
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(child_stdout, child_stdin) = (p.stdout, p.stdin)
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(child_stdout, child_stdin) = popen2.popen2(["mycmd", "myarg"], bufsize, mode)
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==>
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p = Popen(["mycmd", "myarg"], bufsize=bufsize,
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stdin=PIPE, stdout=PIPE, close_fds=True)
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(child_stdout, child_stdin) = (p.stdout, p.stdin)
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The popen2.Popen3 and popen3.Popen4 basically works as subprocess.Popen,
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except that:
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* subprocess.Popen raises an exception if the execution fails
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* the capturestderr argument is replaced with the stderr argument.
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* stdin=PIPE and stdout=PIPE must be specified.
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* popen2 closes all filedescriptors by default, but you have to specify
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close_fds=True with subprocess.Popen.
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"""
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import sys
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mswindows = (sys.platform == "win32")
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import os
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import types
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import traceback
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# Exception classes used by this module.
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class CalledProcessError(Exception):
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"""This exception is raised when a process run by check_call() returns
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a non-zero exit status. The exit status will be stored in the
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returncode attribute."""
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def __init__(self, returncode, cmd):
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self.returncode = returncode
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self.cmd = cmd
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def __str__(self):
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return "Command '%s' returned non-zero exit status %d" % (self.cmd, self.returncode)
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if mswindows:
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import threading
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import msvcrt
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if 0: # <-- change this to use pywin32 instead of the _subprocess driver
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import pywintypes
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from win32api import GetStdHandle, STD_INPUT_HANDLE, \
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STD_OUTPUT_HANDLE, STD_ERROR_HANDLE
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from win32api import GetCurrentProcess, DuplicateHandle, \
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GetModuleFileName, GetVersion
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from win32con import DUPLICATE_SAME_ACCESS, SW_HIDE
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from win32pipe import CreatePipe
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from win32process import CreateProcess, STARTUPINFO, \
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GetExitCodeProcess, STARTF_USESTDHANDLES, \
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STARTF_USESHOWWINDOW, CREATE_NEW_CONSOLE
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from win32event import WaitForSingleObject, INFINITE, WAIT_OBJECT_0
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else:
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from _subprocess import *
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class STARTUPINFO:
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dwFlags = 0
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hStdInput = None
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hStdOutput = None
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hStdError = None
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wShowWindow = 0
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class pywintypes:
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error = IOError
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else:
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import select
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import errno
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import fcntl
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import pickle
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__all__ = ["Popen", "PIPE", "STDOUT", "call", "check_call", "CalledProcessError"]
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try:
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MAXFD = os.sysconf("SC_OPEN_MAX")
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except:
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MAXFD = 256
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# True/False does not exist on 2.2.0
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try:
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False
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except NameError:
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False = 0
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True = 1
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_active = []
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def _cleanup():
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for inst in _active[:]:
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if inst.poll(_deadstate=sys.maxint) >= 0:
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try:
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_active.remove(inst)
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except ValueError:
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# This can happen if two threads create a new Popen instance.
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# It's harmless that it was already removed, so ignore.
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pass
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PIPE = -1
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STDOUT = -2
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def call(*popenargs, **kwargs):
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"""Run command with arguments. Wait for command to complete, then
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return the returncode attribute.
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The arguments are the same as for the Popen constructor. Example:
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retcode = call(["ls", "-l"])
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"""
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return Popen(*popenargs, **kwargs).wait()
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def check_call(*popenargs, **kwargs):
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"""Run command with arguments. Wait for command to complete. If
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the exit code was zero then return, otherwise raise
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CalledProcessError. The CalledProcessError object will have the
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return code in the returncode attribute.
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The arguments are the same as for the Popen constructor. Example:
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check_call(["ls", "-l"])
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"""
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retcode = call(*popenargs, **kwargs)
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cmd = kwargs.get("args")
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if cmd is None:
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cmd = popenargs[0]
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if retcode:
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raise CalledProcessError(retcode, cmd)
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return retcode
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def list2cmdline(seq):
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"""
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Translate a sequence of arguments into a command line
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string, using the same rules as the MS C runtime:
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1) Arguments are delimited by white space, which is either a
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space or a tab.
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2) A string surrounded by double quotation marks is
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interpreted as a single argument, regardless of white space
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contained within. A quoted string can be embedded in an
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argument.
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3) A double quotation mark preceded by a backslash is
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interpreted as a literal double quotation mark.
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4) Backslashes are interpreted literally, unless they
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immediately precede a double quotation mark.
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5) If backslashes immediately precede a double quotation mark,
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every pair of backslashes is interpreted as a literal
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backslash. If the number of backslashes is odd, the last
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backslash escapes the next double quotation mark as
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described in rule 3.
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"""
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# See
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# http://msdn.microsoft.com/library/en-us/vccelng/htm/progs_12.asp
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result = []
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needquote = False
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for arg in seq:
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bs_buf = []
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# Add a space to separate this argument from the others
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if result:
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result.append(' ')
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needquote = (" " in arg) or ("\t" in arg) or arg == ""
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if needquote:
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result.append('"')
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for c in arg:
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if c == '\\':
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# Don't know if we need to double yet.
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bs_buf.append(c)
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elif c == '"':
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# Double backspaces.
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result.append('\\' * len(bs_buf)*2)
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bs_buf = []
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result.append('\\"')
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else:
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# Normal char
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if bs_buf:
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result.extend(bs_buf)
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bs_buf = []
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result.append(c)
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# Add remaining backspaces, if any.
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if bs_buf:
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result.extend(bs_buf)
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if needquote:
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result.extend(bs_buf)
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result.append('"')
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return ''.join(result)
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class Popen(object):
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def __init__(self, args, bufsize=0, executable=None,
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stdin=None, stdout=None, stderr=None,
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preexec_fn=None, close_fds=False, shell=False,
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cwd=None, env=None, universal_newlines=False,
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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:
|
|
raise ValueError("close_fds is not supported on Windows "
|
|
"platforms")
|
|
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)
|
|
|
|
# On Windows, you cannot just redirect one or two handles: You
|
|
# either have to redirect all three or none. If the subprocess
|
|
# user has only redirected one or two handles, we are
|
|
# automatically creating PIPEs for the rest. We should close
|
|
# these after the process is started. See bug #1124861.
|
|
if mswindows:
|
|
if stdin is None and p2cwrite is not None:
|
|
os.close(p2cwrite)
|
|
p2cwrite = None
|
|
if stdout is None and c2pread is not None:
|
|
os.close(c2pread)
|
|
c2pread = None
|
|
if stderr is None and errread is not None:
|
|
os.close(errread)
|
|
errread = None
|
|
|
|
if p2cwrite:
|
|
self.stdin = os.fdopen(p2cwrite, 'wb', bufsize)
|
|
if c2pread:
|
|
if universal_newlines:
|
|
self.stdout = os.fdopen(c2pread, 'rU', bufsize)
|
|
else:
|
|
self.stdout = os.fdopen(c2pread, 'rb', bufsize)
|
|
if errread:
|
|
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):
|
|
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.poll(_deadstate=sys.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()
|
|
elif self.stderr:
|
|
stderr = self.stderr.read()
|
|
self.wait()
|
|
return (stdout, stderr)
|
|
|
|
return self._communicate(input)
|
|
|
|
|
|
if mswindows:
|
|
#
|
|
# Windows methods
|
|
#
|
|
def _get_handles(self, stdin, stdout, stderr):
|
|
"""Construct and return tupel 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 = GetStdHandle(STD_INPUT_HANDLE)
|
|
if p2cread is not None:
|
|
pass
|
|
elif stdin is None or stdin == PIPE:
|
|
p2cread, p2cwrite = CreatePipe(None, 0)
|
|
# Detach and turn into fd
|
|
p2cwrite = p2cwrite.Detach()
|
|
p2cwrite = msvcrt.open_osfhandle(p2cwrite, 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 = GetStdHandle(STD_OUTPUT_HANDLE)
|
|
if c2pwrite is not None:
|
|
pass
|
|
elif stdout is None or stdout == PIPE:
|
|
c2pread, c2pwrite = CreatePipe(None, 0)
|
|
# Detach and turn into fd
|
|
c2pread = c2pread.Detach()
|
|
c2pread = msvcrt.open_osfhandle(c2pread, 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 = GetStdHandle(STD_ERROR_HANDLE)
|
|
if errwrite is not None:
|
|
pass
|
|
elif stderr is None or stderr == PIPE:
|
|
errread, errwrite = CreatePipe(None, 0)
|
|
# Detach and turn into fd
|
|
errread = errread.Detach()
|
|
errread = msvcrt.open_osfhandle(errread, 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 DuplicateHandle(GetCurrentProcess(), handle,
|
|
GetCurrentProcess(), 0, 1,
|
|
DUPLICATE_SAME_ACCESS)
|
|
|
|
|
|
def _find_w9xpopen(self):
|
|
"""Find and return absolut path to w9xpopen.exe"""
|
|
w9xpopen = os.path.join(os.path.dirname(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 |= STARTF_USESTDHANDLES
|
|
startupinfo.hStdInput = p2cread
|
|
startupinfo.hStdOutput = c2pwrite
|
|
startupinfo.hStdError = errwrite
|
|
|
|
if shell:
|
|
startupinfo.dwFlags |= STARTF_USESHOWWINDOW
|
|
startupinfo.wShowWindow = SW_HIDE
|
|
comspec = os.environ.get("COMSPEC", "cmd.exe")
|
|
args = comspec + " /c " + args
|
|
if (GetVersion() >= 0x80000000L 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 |= CREATE_NEW_CONSOLE
|
|
|
|
# Start the process
|
|
try:
|
|
hp, ht, pid, tid = CreateProcess(executable, args,
|
|
# no special security
|
|
None, None,
|
|
# must inherit handles to pass std
|
|
# handles
|
|
1,
|
|
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)
|
|
|
|
# Retain the process handle, but close the thread handle
|
|
self._child_created = True
|
|
self._handle = hp
|
|
self.pid = pid
|
|
ht.Close()
|
|
|
|
# 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()
|
|
|
|
|
|
def poll(self, _deadstate=None):
|
|
"""Check if child process has terminated. Returns returncode
|
|
attribute."""
|
|
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:
|
|
obj = WaitForSingleObject(self._handle, INFINITE)
|
|
self.returncode = 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)
|
|
|
|
else:
|
|
#
|
|
# POSIX methods
|
|
#
|
|
def _get_handles(self, stdin, stdout, stderr):
|
|
"""Construct and return tupel 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):
|
|
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:
|
|
if sys.platform == 'plan9':
|
|
args = ["/bin/ape/sh", "-c"] + args
|
|
else:
|
|
args = ["/bin/sh", "-c"] + args
|
|
|
|
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()
|
|
self._set_cloexec_flag(errpipe_write)
|
|
|
|
self.pid = os.fork()
|
|
self._child_created = True
|
|
if self.pid == 0:
|
|
# Child
|
|
try:
|
|
# Close parent's pipe ends
|
|
if p2cwrite:
|
|
os.close(p2cwrite)
|
|
if c2pread:
|
|
os.close(c2pread)
|
|
if errread:
|
|
os.close(errread)
|
|
os.close(errpipe_read)
|
|
|
|
# Dup fds for child
|
|
if p2cread:
|
|
os.dup2(p2cread, 0)
|
|
if c2pwrite:
|
|
os.dup2(c2pwrite, 1)
|
|
if errwrite:
|
|
os.dup2(errwrite, 2)
|
|
|
|
# Close pipe fds. Make sure we don't close the same
|
|
# fd more than once, or standard fds.
|
|
if p2cread and p2cread not in (0,):
|
|
os.close(p2cread)
|
|
if c2pwrite and c2pwrite not in (p2cread, 1):
|
|
os.close(c2pwrite)
|
|
if errwrite 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:
|
|
apply(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
|
|
os.close(errpipe_write)
|
|
if p2cread and p2cwrite:
|
|
os.close(p2cread)
|
|
if c2pwrite and c2pread:
|
|
os.close(c2pwrite)
|
|
if errwrite and errread:
|
|
os.close(errwrite)
|
|
|
|
# Wait for exec to fail or succeed; possibly raising exception
|
|
data = os.read(errpipe_read, 1048576) # Exceptions limited to 1 MB
|
|
os.close(errpipe_read)
|
|
if data != "":
|
|
os.waitpid(self.pid, 0)
|
|
child_exception = pickle.loads(data)
|
|
raise child_exception
|
|
|
|
|
|
def _handle_exitstatus(self, sts):
|
|
if os.WIFSIGNALED(sts):
|
|
self.returncode = -os.WTERMSIG(sts)
|
|
elif os.WIFEXITED(sts):
|
|
self.returncode = os.WEXITSTATUS(sts)
|
|
else:
|
|
# Should never happen
|
|
raise RuntimeError("Unknown child exit status!")
|
|
|
|
|
|
def poll(self, _deadstate=None):
|
|
"""Check if child process has terminated. Returns returncode
|
|
attribute."""
|
|
if self.returncode is None:
|
|
try:
|
|
pid, sts = os.waitpid(self.pid, os.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 = os.waitpid(self.pid, 0)
|
|
self._handle_exitstatus(sts)
|
|
return self.returncode
|
|
|
|
|
|
def _communicate(self, input):
|
|
read_set = []
|
|
write_set = []
|
|
stdout = None # Return
|
|
stderr = None # Return
|
|
|
|
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 input:
|
|
write_set.append(self.stdin)
|
|
else:
|
|
self.stdin.close()
|
|
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:
|
|
rlist, wlist, xlist = select.select(read_set, write_set, [])
|
|
|
|
if self.stdin in wlist:
|
|
# When select has indicated that the file is writable,
|
|
# we can write up to PIPE_BUF bytes without risk
|
|
# blocking. POSIX defines PIPE_BUF >= 512
|
|
bytes_written = os.write(self.stdin.fileno(), buffer(input, input_offset, 512))
|
|
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)
|
|
|
|
# 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 _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()
|