log_output : moved from os.fork to multiprocessing.Process
This commit is contained in:
parent
440e71ff13
commit
9af964a6d6
@ -29,6 +29,7 @@
|
||||
import re
|
||||
import select
|
||||
import inspect
|
||||
import multiprocessing
|
||||
|
||||
import llnl.util.tty as tty
|
||||
import llnl.util.tty.color as color
|
||||
@ -103,21 +104,21 @@ class log_output(object):
|
||||
"""Redirects output and error of enclosed block to a file.
|
||||
|
||||
Usage:
|
||||
with log_output(open('logfile.txt', 'w')):
|
||||
with log_output('logfile.txt', 'w'):
|
||||
# do things ... output will be logged.
|
||||
|
||||
or:
|
||||
with log_output(open('logfile.txt', 'w'), echo=True):
|
||||
with log_output('logfile.txt', echo=True):
|
||||
# do things ... output will be logged
|
||||
# and also printed to stdout.
|
||||
|
||||
Closes the provided stream when done with the block.
|
||||
Opens a stream in 'w' mode at instance creation and closes
|
||||
it at instance deletion
|
||||
If echo is True, also prints the output to stdout.
|
||||
"""
|
||||
def __init__(self, stream, echo=False, force_color=False, debug=False):
|
||||
self.stream = stream
|
||||
|
||||
# various output options
|
||||
def __init__(self, filename, echo=False, force_color=False, debug=False):
|
||||
self.filename = filename
|
||||
# Various output options
|
||||
self.echo = echo
|
||||
self.force_color = force_color
|
||||
self.debug = debug
|
||||
@ -125,133 +126,92 @@ def __init__(self, stream, echo=False, force_color=False, debug=False):
|
||||
# Default is to try file-descriptor reassignment unless the system
|
||||
# out/err streams do not have an associated file descriptor
|
||||
self.directAssignment = False
|
||||
self.read, self.write = os.pipe()
|
||||
|
||||
def trace(self, frame, event, arg):
|
||||
"""Jumps to __exit__ on the child process."""
|
||||
raise _SkipWithBlock()
|
||||
|
||||
# Spawn a daemon that writes what it reads from a pipe
|
||||
self.p = multiprocessing.Process(target=self._forward_redirected_pipe, args=(self.read,), name='logger_daemon')
|
||||
self.p.daemon = True
|
||||
self.p.start()
|
||||
|
||||
def __enter__(self):
|
||||
"""Redirect output from the with block to a file.
|
||||
|
||||
This forks the with block as a separate process, with stdout
|
||||
and stderr redirected back to the parent via a pipe. If
|
||||
echo is set, also writes to standard out.
|
||||
|
||||
Hijacks stdout / stderr and writes to the pipe
|
||||
connected to the logger daemon
|
||||
"""
|
||||
# remember these values for later.
|
||||
self._force_color = color._force_color
|
||||
self._debug = tty._debug
|
||||
# Redirect this output to a pipe
|
||||
self._redirect_to_pipe(self.write)
|
||||
|
||||
read, write = os.pipe()
|
||||
def _forward_redirected_pipe(self, read):
|
||||
# Parent: read from child, skip the with block.
|
||||
read_file = os.fdopen(read, 'r', 0)
|
||||
with open(self.filename, 'w') as log_file:
|
||||
with keyboard_input(sys.stdin):
|
||||
while True:
|
||||
rlist, _, _ = select.select([read_file, sys.stdin], [], [])
|
||||
if not rlist:
|
||||
break
|
||||
|
||||
self.pid = os.fork()
|
||||
if self.pid:
|
||||
# Parent: read from child, skip the with block.
|
||||
os.close(write)
|
||||
# Allow user to toggle echo with 'v' key.
|
||||
# Currently ignores other chars.
|
||||
if sys.stdin in rlist:
|
||||
if sys.stdin.read(1) == 'v':
|
||||
self.echo = not self.echo
|
||||
|
||||
read_file = os.fdopen(read, 'r', 0)
|
||||
with self.stream as log_file:
|
||||
with keyboard_input(sys.stdin):
|
||||
while True:
|
||||
rlist, w, x = select.select([read_file, sys.stdin], [], [])
|
||||
if not rlist:
|
||||
# Handle output from the with block process.
|
||||
if read_file in rlist:
|
||||
line = read_file.readline()
|
||||
if not line:
|
||||
break
|
||||
|
||||
# Allow user to toggle echo with 'v' key.
|
||||
# Currently ignores other chars.
|
||||
if sys.stdin in rlist:
|
||||
if sys.stdin.read(1) == 'v':
|
||||
self.echo = not self.echo
|
||||
# Echo to stdout if requested.
|
||||
if self.echo:
|
||||
sys.stdout.write(line)
|
||||
|
||||
# handle output from the with block process.
|
||||
if read_file in rlist:
|
||||
line = read_file.readline()
|
||||
if not line:
|
||||
break
|
||||
# Stripped output to log file.
|
||||
log_file.write(_strip(line))
|
||||
log_file.flush()
|
||||
|
||||
# Echo to stdout if requested.
|
||||
if self.echo:
|
||||
sys.stdout.write(line)
|
||||
|
||||
# Stripped output to log file.
|
||||
log_file.write(_strip(line))
|
||||
|
||||
read_file.flush()
|
||||
read_file.close()
|
||||
|
||||
# Set a trace function to skip the with block.
|
||||
sys.settrace(lambda *args, **keys: None)
|
||||
frame = inspect.currentframe(1)
|
||||
frame.f_trace = self.trace
|
||||
|
||||
else:
|
||||
# Child: redirect output, execute the with block.
|
||||
os.close(read)
|
||||
|
||||
try:
|
||||
# Save old stdout and stderr
|
||||
self._stdout = os.dup(sys.stdout.fileno())
|
||||
self._stderr = os.dup(sys.stderr.fileno())
|
||||
|
||||
# redirect to the pipe.
|
||||
os.dup2(write, sys.stdout.fileno())
|
||||
os.dup2(write, sys.stderr.fileno())
|
||||
except AttributeError:
|
||||
self.directAssignment = True
|
||||
self._stdout = sys.stdout
|
||||
self._stderr = sys.stderr
|
||||
output_redirect = os.fdopen(write, 'w')
|
||||
sys.stdout = output_redirect
|
||||
sys.stderr = output_redirect
|
||||
|
||||
if self.force_color:
|
||||
color._force_color = True
|
||||
|
||||
if self.debug:
|
||||
tty._debug = True
|
||||
def _redirect_to_pipe(self, write):
|
||||
try:
|
||||
# Save old stdout and stderr
|
||||
self._stdout = os.dup(sys.stdout.fileno())
|
||||
self._stderr = os.dup(sys.stderr.fileno())
|
||||
|
||||
# redirect to the pipe.
|
||||
os.dup2(write, sys.stdout.fileno())
|
||||
os.dup2(write, sys.stderr.fileno())
|
||||
except AttributeError:
|
||||
self.directAssignment = True
|
||||
self._stdout = sys.stdout
|
||||
self._stderr = sys.stderr
|
||||
output_redirect = os.fdopen(write, 'w')
|
||||
sys.stdout = output_redirect
|
||||
sys.stderr = output_redirect
|
||||
if self.force_color:
|
||||
color._force_color = True
|
||||
if self.debug:
|
||||
tty._debug = True
|
||||
|
||||
def __exit__(self, exc_type, exception, traceback):
|
||||
"""Exits on child, handles skipping the with block on parent."""
|
||||
# Child should just exit here.
|
||||
if self.pid == 0:
|
||||
# Flush the log to disk.
|
||||
sys.stdout.flush()
|
||||
sys.stderr.flush()
|
||||
|
||||
if exception:
|
||||
# Restore stdout on the child if there's an exception,
|
||||
# and let it be raised normally.
|
||||
#
|
||||
# This assumes that even if the exception is caught,
|
||||
# the child will exit with a nonzero return code. If
|
||||
# it doesn't, the child process will continue running.
|
||||
#
|
||||
# TODO: think about how this works outside install.
|
||||
# TODO: ideally would propagate exception to parent...
|
||||
if self.directAssignment:
|
||||
sys.stdout = self._stdout
|
||||
sys.stderr = self._stderr
|
||||
else:
|
||||
os.dup2(self._stdout, sys.stdout.fileno())
|
||||
os.dup2(self._stderr, sys.stderr.fileno())
|
||||
|
||||
return False
|
||||
|
||||
else:
|
||||
# Die quietly if there was no exception.
|
||||
os._exit(0)
|
||||
|
||||
else:
|
||||
# If the child exited badly, parent also should exit.
|
||||
pid, returncode = os.waitpid(self.pid, 0)
|
||||
if returncode != 0:
|
||||
os._exit(1)
|
||||
"""Plugs back the original file descriptors
|
||||
for stdout and stderr
|
||||
"""
|
||||
# Flush the log to disk.
|
||||
sys.stdout.flush()
|
||||
sys.stderr.flush()
|
||||
os.dup2(self._stdout, sys.stdout.fileno())
|
||||
os.dup2(self._stderr, sys.stderr.fileno())
|
||||
|
||||
# restore output options.
|
||||
color._force_color = self._force_color
|
||||
tty._debug = self._debug
|
||||
|
||||
# Suppresses exception if it's our own.
|
||||
return exc_type is _SkipWithBlock
|
||||
def __del__(self):
|
||||
"""Closes the pipes and joins the daemon"""
|
||||
os.close(self.write)
|
||||
self.p.join()
|
||||
os.close(self.read)
|
||||
|
Loading…
Reference in New Issue
Block a user