def exec_cmd(cmd, env=None):
"""
Execute cmd in an external process, collect its output and returncode
:param cmd: an iterator of strings to be passed as exec(2)'s argv
:param env: an optional dictionary to be placed as environment variables
of the external process. If None, the environment of the
calling process is used.
:returns: a 3-tuple of the process's
(returncode, stdout content, stderr content.)
This is a bare-bones version of `commands.execCmd`. Unlike the latter, this
function
* uses Vdsm cpu pinning, and must not be used for long CPU-bound processes.
* does not guarantee to kill underlying process if CPopen.communicate()
raises. Commands that access shared storage may not use this api.
* does not hide passwords in logs if they are passed in cmd
"""
logging.debug(command_log_line(cmd))
p = CPopen(
cmd, close_fds=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
env=env)
out, err = p.communicate()
logging.debug(retcode_log_line(p.returncode, err=err))
return p.returncode, out, err
def execCmd(command, sudo=False, cwd=None, data=None, raw=False,
printable=None, env=None, sync=True, nice=None, ioclass=None,
ioclassdata=None, setsid=False, execCmdLogger=logging.root,
deathSignal=None, resetCpuAffinity=True):
"""
Executes an external command, optionally via sudo.
IMPORTANT NOTE: the new process would receive `deathSignal` when the
controlling thread dies, which may not be what you intended: if you create
a temporary thread, spawn a sync=False sub-process, and have the thread
finish, the new subprocess would die immediately.
"""
command = cmdutils.wrap_command(command, with_ioclass=ioclass,
ioclassdata=ioclassdata, with_nice=nice,
with_setsid=setsid, with_sudo=sudo,
reset_cpu_affinity=resetCpuAffinity)
# Unsubscriptable objects (e.g. generators) need conversion
if not callable(getattr(command, '__getitem__', None)):
command = tuple(command)
if not printable:
printable = command
execCmdLogger.debug(command_log_line(printable, cwd=cwd))
extra = {}
extra['stderr'] = subprocess.PIPE
extra['stdout'] = subprocess.PIPE
if deathSignal is not None:
extra['deathSignal'] = deathSignal
p = CPopen(command, close_fds=True, cwd=cwd, env=env, **extra)
if not sync:
p = AsyncProc(p)
if data is not None:
p.stdin.write(data)
p.stdin.flush()
return p
with terminating(p):
(out, err) = p.communicate(data)
if out is None:
# Prevent splitlines() from barfing later on
out = ""
execCmdLogger.debug(retcode_log_line(p.returncode, err=err))
if not raw:
out = out.splitlines(False)
err = err.splitlines(False)
return p.returncode, out, err
def _child_processes(self):
proc = CPopen(self.PGREP_CMD, stdin=None, stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = proc.communicate()
# EXIT STATUS
# 0 One or more processes matched the criteria.
# 1 No processes matched.
if proc.returncode not in (0, 1):
raise RuntimeError("Error running pgrep: [%d] %s"
% (proc.returncode, err))
return frozenset(int(pid) for pid in out.splitlines())
def exec_sync(cmds):
logging.debug(cmdutils.command_log_line(cmds))
p = Popen(
cmds, close_fds=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
out, err = p.communicate()
logging.debug(cmdutils.retcode_log_line(p.returncode, err=err))
return p.returncode, out, err
def _child_processes(self):
proc = CPopen(self.PGREP_CMD,
stdin=None,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = proc.communicate()
# EXIT STATUS
# 0 One or more processes matched the criteria.
# 1 No processes matched.
if proc.returncode not in (0, 1):
raise RuntimeError("Error running pgrep: [%d] %s" %
(proc.returncode, err))
return frozenset(int(pid) for pid in out.splitlines())
def exec_sync_bytes(cmds):
logging.debug(cmdutils.command_log_line(cmds))
p = Popen(cmds,
close_fds=True,
stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
out, err = p.communicate()
logging.debug(cmdutils.retcode_log_line(p.returncode, err=err))
return p.returncode, out, err
def execCmd(command,
sudo=False,
cwd=None,
data=None,
raw=False,
printable=None,
env=None,
sync=True,
nice=None,
ioclass=None,
ioclassdata=None,
setsid=False,
execCmdLogger=logging.root,
deathSignal=None,
resetCpuAffinity=True):
"""
Executes an external command, optionally via sudo.
IMPORTANT NOTE: the new process would receive `deathSignal` when the
controlling thread dies, which may not be what you intended: if you create
a temporary thread, spawn a sync=False sub-process, and have the thread
finish, the new subprocess would die immediately.
"""
command = cmdutils.wrap_command(command,
with_ioclass=ioclass,
ioclassdata=ioclassdata,
with_nice=nice,
with_setsid=setsid,
with_sudo=sudo,
reset_cpu_affinity=resetCpuAffinity)
# Unsubscriptable objects (e.g. generators) need conversion
if not callable(getattr(command, '__getitem__', None)):
command = tuple(command)
if not printable:
printable = command
execCmdLogger.debug(command_log_line(printable, cwd=cwd))
extra = {}
extra['stderr'] = subprocess.PIPE
extra['stdout'] = subprocess.PIPE
if deathSignal is not None:
extra['deathSignal'] = deathSignal
p = CPopen(command, close_fds=True, cwd=cwd, env=env, **extra)
if not sync:
p = AsyncProc(p)
if data is not None:
p.stdin.write(data)
p.stdin.flush()
return p
with terminating(p):
(out, err) = p.communicate(data)
if out is None:
# Prevent splitlines() from barfing later on
out = ""
execCmdLogger.debug(retcode_log_line(p.returncode, err=err))
if not raw:
out = out.splitlines(False)
err = err.splitlines(False)
return p.returncode, out, err
