shell.py 4.41 KB
Newer Older
Johannes Bechberger's avatar
Johannes Bechberger committed
1
# source: https://github.com/libfirm/sisyphus, but slightly modified to support Windows
Johannes Bechberger's avatar
Johannes Bechberger committed
2 3 4 5 6

"""
Convenience function
Alternative to subprocess and os.system
"""
7
import os
Johannes Bechberger's avatar
Johannes Bechberger committed
8
import shlex
Johannes Bechberger's avatar
Johannes Bechberger committed
9
import subprocess
10 11
has_resource_module = True
try:
Johannes Bechberger's avatar
Johannes Bechberger committed
12
    import resource
13
except ImportError:
Johannes Bechberger's avatar
Johannes Bechberger committed
14 15
    has_resource_module = False
    pass
16
	
Johannes Bechberger's avatar
Johannes Bechberger committed
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
import sys
import signal
import threading

import logging
_LOG = logging.getLogger("sisyphus")

_EXIT_CODES = dict((-k, v) for v, k in signal.__dict__.items() if v.startswith('SIG'))
del _EXIT_CODES[0]


class SigKill(Exception):
    def __init__(self, retcode, name):
        self.retcode = retcode
        self.name = name


def _lower_rlimit(res, limit):
35 36
    if not has_resource_module:
        return
Johannes Bechberger's avatar
Johannes Bechberger committed
37 38 39 40 41 42 43 44 45
    (soft, hard) = resource.getrlimit(res)
    if soft > limit or soft == resource.RLIM_INFINITY:
        soft = limit
    if hard > limit or hard == resource.RLIM_INFINITY:
        hard = limit
    resource.setrlimit(res, (soft, hard))


class _Execute(object):
46
    def __init__(self, cmd, timeout, env, rlimit, input_str):
Johannes Bechberger's avatar
Johannes Bechberger committed
47 48 49 50 51 52
        self.cmd       = cmd
        self.timeout   = timeout
        self.env       = env
        self.proc      = None
        self.exception = None
        self.rlimit    = rlimit
53
        self.input_str = input_str
Johannes Bechberger's avatar
Johannes Bechberger committed
54 55 56 57 58 59 60 61 62 63 64
        MB = 1024 * 1024
        if not 'RLIMIT_CORE' in rlimit:
            rlimit['RLIMIT_CORE'] = 0
        if not 'RLIMIT_DATA' in rlimit:
            rlimit['RLIMIT_DATA'] = 1024 * MB
        if not 'RLIMIT_STACK' in rlimit:
            rlimit['RLIMIT_STACK'] = 1024 * MB
        if not 'RLIMIT_FSIZE' in rlimit:
            rlimit['RLIMIT_FSIZE'] = 512 * MB

    def _set_rlimit(self):
65 66
        if not has_resource_module:
            return
Johannes Bechberger's avatar
Johannes Bechberger committed
67 68 69 70 71 72 73
        if self.timeout > 0.0:
            _lower_rlimit(resource.RLIMIT_CPU, self.timeout)
        for k,v in self.rlimit.items():
            _lower_rlimit(getattr(resource,k), v)

    def _run_process(self):
        try:
74 75 76
            prexec_args = {}
            if has_resource_module:
                prexec_args["preexec_fn"] = self._set_rlimit
Johannes Bechberger's avatar
Johannes Bechberger committed
77 78 79
            self.proc = subprocess.Popen(self.cmd,
                                         stdout=subprocess.PIPE,
                                         stderr=subprocess.PIPE,
80
                                         stdin=subprocess.PIPE if self.input_str else None,
81
                                         env=self.env,
Johannes Bechberger's avatar
Johannes Bechberger committed
82
                                         shell=True,
83
                                         **prexec_args)
84 85 86 87
            #if self.input_str:
            #    self.proc.stdin.write(self.input_str.decode)
            input_bytes = self.input_str.encode() if self.input_str else None
            x = self.proc.communicate(input=input_bytes, timeout=self.timeout if self.timeout > 0.0 else None)
Johannes Bechberger's avatar
Johannes Bechberger committed
88 89
            self.out, self.err = x
            self.returncode = self.proc.returncode
90 91 92 93 94 95
        except subprocess.TimeoutExpired as t:
            self.returncode = -signal.SIGXCPU
            self.out = bytearray()
            self.err = bytearray()
        #except Exception as e:
        #    self.exception = e
Johannes Bechberger's avatar
Johannes Bechberger committed
96 97

    def run(self):
98
        self._run_process()
Johannes Bechberger's avatar
Johannes Bechberger committed
99 100 101 102 103 104 105 106 107

        # Usually python can recognize application terminations triggered by
        # signals, but somehow it doesn't do this for java (I suspect, that java
        # catches the signals itself but then shuts down more 'cleanly' than it
        # should. Calculate to python convention returncode
        if self.returncode > 127:
            self.returncode = 128 - self.returncode
        if self.returncode in _EXIT_CODES:
            _LOG.debug("returncode %d recognized as '%s'" % (self.returncode, _EXIT_CODES[self.returncode]))
108
            raise SigKill(-self.returncode, _EXIT_CODES[self.returncode] + ": " + os.strerror(-self.returncode))
Johannes Bechberger's avatar
Johannes Bechberger committed
109 110
        return (self.out, self.err, self.returncode)

111
def execute(cmd, env=None, timeout=0, rlimit=None, propagate_sigint=True, input_str = None):
Johannes Bechberger's avatar
Johannes Bechberger committed
112 113 114 115
    """Execute a command and return stderr and stdout data"""
    if not rlimit:
        rlimit = dict()
    if cmd is str:
Johannes Bechberger's avatar
Johannes Bechberger committed
116 117
        pass
        #cmd = filter(lambda x: x, cmd.split(' '))
118
    else:
Johannes Bechberger's avatar
Johannes Bechberger committed
119
        #cmd = shlex.split(cmd[0]) + cmd[1:]
Johannes Bechberger's avatar
Fix #36  
Johannes Bechberger committed
120
        cmd = " ".join(shlex.quote(c) for c in cmd)
121
    exc = _Execute(cmd, timeout, env, rlimit, input_str)
Johannes Bechberger's avatar
Johannes Bechberger committed
122 123 124 125 126 127 128 129 130
    (out, err, returncode) = exc.run()
    if returncode == -signal.SIGINT:
        raise KeyboardInterrupt
    return (out, err, returncode)


if __name__ == "__main__":
    out, err, retcode = execute("hostname")
    print (out)