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citadel/poky/bitbake/lib/bb/process.py

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import logging
import signal
import subprocess
import errno
import select
logger = logging.getLogger('BitBake.Process')
def subprocess_setup():
# Python installs a SIGPIPE handler by default. This is usually not what
# non-Python subprocesses expect.
signal.signal(signal.SIGPIPE, signal.SIG_DFL)
class CmdError(RuntimeError):
def __init__(self, command, msg=None):
self.command = command
self.msg = msg
def __str__(self):
if not isinstance(self.command, str):
cmd = subprocess.list2cmdline(self.command)
else:
cmd = self.command
msg = "Execution of '%s' failed" % cmd
if self.msg:
msg += ': %s' % self.msg
return msg
class NotFoundError(CmdError):
def __str__(self):
return CmdError.__str__(self) + ": command not found"
class ExecutionError(CmdError):
def __init__(self, command, exitcode, stdout = None, stderr = None):
CmdError.__init__(self, command)
self.exitcode = exitcode
self.stdout = stdout
self.stderr = stderr
def __str__(self):
message = ""
if self.stderr:
message += self.stderr
if self.stdout:
message += self.stdout
if message:
message = ":\n" + message
return (CmdError.__str__(self) +
" with exit code %s" % self.exitcode + message)
class Popen(subprocess.Popen):
defaults = {
"close_fds": True,
"preexec_fn": subprocess_setup,
"stdout": subprocess.PIPE,
"stderr": subprocess.STDOUT,
"stdin": subprocess.PIPE,
"shell": False,
}
def __init__(self, *args, **kwargs):
options = dict(self.defaults)
options.update(kwargs)
subprocess.Popen.__init__(self, *args, **options)
def _logged_communicate(pipe, log, input, extrafiles):
if pipe.stdin:
if input is not None:
pipe.stdin.write(input)
pipe.stdin.close()
outdata, errdata = [], []
rin = []
if pipe.stdout is not None:
bb.utils.nonblockingfd(pipe.stdout.fileno())
rin.append(pipe.stdout)
if pipe.stderr is not None:
bb.utils.nonblockingfd(pipe.stderr.fileno())
rin.append(pipe.stderr)
for fobj, _ in extrafiles:
bb.utils.nonblockingfd(fobj.fileno())
rin.append(fobj)
def readextras(selected):
for fobj, func in extrafiles:
if fobj in selected:
try:
data = fobj.read()
except IOError as err:
if err.errno == errno.EAGAIN or err.errno == errno.EWOULDBLOCK:
data = None
if data is not None:
func(data)
def read_all_pipes(log, rin, outdata, errdata):
rlist = rin
stdoutbuf = b""
stderrbuf = b""
try:
r,w,e = select.select (rlist, [], [], 1)
except OSError as e:
if e.errno != errno.EINTR:
raise
readextras(r)
if pipe.stdout in r:
data = stdoutbuf + pipe.stdout.read()
if data is not None and len(data) > 0:
try:
data = data.decode("utf-8")
outdata.append(data)
log.write(data)
log.flush()
stdoutbuf = b""
except UnicodeDecodeError:
stdoutbuf = data
if pipe.stderr in r:
data = stderrbuf + pipe.stderr.read()
if data is not None and len(data) > 0:
try:
data = data.decode("utf-8")
errdata.append(data)
log.write(data)
log.flush()
stderrbuf = b""
except UnicodeDecodeError:
stderrbuf = data
try:
# Read all pipes while the process is open
while pipe.poll() is None:
read_all_pipes(log, rin, outdata, errdata)
# Pocess closed, drain all pipes...
read_all_pipes(log, rin, outdata, errdata)
finally:
log.flush()
if pipe.stdout is not None:
pipe.stdout.close()
if pipe.stderr is not None:
pipe.stderr.close()
return ''.join(outdata), ''.join(errdata)
def run(cmd, input=None, log=None, extrafiles=None, **options):
"""Convenience function to run a command and return its output, raising an
exception when the command fails"""
if not extrafiles:
extrafiles = []
if isinstance(cmd, str) and not "shell" in options:
options["shell"] = True
try:
pipe = Popen(cmd, **options)
except OSError as exc:
if exc.errno == 2:
raise NotFoundError(cmd)
else:
raise CmdError(cmd, exc)
if log:
stdout, stderr = _logged_communicate(pipe, log, input, extrafiles)
else:
stdout, stderr = pipe.communicate(input)
if not stdout is None:
stdout = stdout.decode("utf-8")
if not stderr is None:
stderr = stderr.decode("utf-8")
if pipe.returncode != 0:
raise ExecutionError(cmd, pipe.returncode, stdout, stderr)
return stdout, stderr