diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/spack/llnl/util/tty/log.py | 130 |
1 files changed, 83 insertions, 47 deletions
diff --git a/lib/spack/llnl/util/tty/log.py b/lib/spack/llnl/util/tty/log.py index 10516e59d2..e608992642 100644 --- a/lib/spack/llnl/util/tty/log.py +++ b/lib/spack/llnl/util/tty/log.py @@ -13,12 +13,18 @@ import re import select import sys import traceback +import signal from contextlib import contextmanager from six import string_types from six import StringIO import llnl.util.tty as tty +try: + import termios +except ImportError: + termios = None + # Use this to strip escape sequences _escape = re.compile(r'\x1b[^m]*m|\x1b\[?1034h') @@ -31,12 +37,26 @@ xon, xoff = '\x11\n', '\x13\n' control = re.compile('(\x11\n|\x13\n)') +@contextmanager +def background_safe(): + signal.signal(signal.SIGTTOU, signal.SIG_IGN) + yield + signal.signal(signal.SIGTTOU, signal.SIG_DFL) + + +def _is_background_tty(): + """Return True iff this process is backgrounded and stdout is a tty""" + if sys.stdout.isatty(): + return os.getpgrp() != os.tcgetpgrp(sys.stdout.fileno()) + return False # not writing to tty, not background + + def _strip(line): """Strip color and control characters from a line.""" return _escape.sub('', line) -class keyboard_input(object): +class _keyboard_input(object): """Context manager to disable line editing and echoing. Use this with ``sys.stdin`` for keyboard input, e.g.:: @@ -81,32 +101,30 @@ class keyboard_input(object): if not self.stream or not self.stream.isatty(): return - try: - # If this fails, self.old_cfg will remain None - import termios - + # If this fails, self.old_cfg will remain None + if termios and not _is_background_tty(): # save old termios settings - fd = self.stream.fileno() - self.old_cfg = termios.tcgetattr(fd) + old_cfg = termios.tcgetattr(self.stream) - # create new settings with canonical input and echo - # disabled, so keypresses are immediate & don't echo. - self.new_cfg = termios.tcgetattr(fd) - self.new_cfg[3] &= ~termios.ICANON - self.new_cfg[3] &= ~termios.ECHO + try: + # create new settings with canonical input and echo + # disabled, so keypresses are immediate & don't echo. + self.new_cfg = termios.tcgetattr(self.stream) + self.new_cfg[3] &= ~termios.ICANON + self.new_cfg[3] &= ~termios.ECHO - # Apply new settings for terminal - termios.tcsetattr(fd, termios.TCSADRAIN, self.new_cfg) + # Apply new settings for terminal + termios.tcsetattr(self.stream, termios.TCSADRAIN, self.new_cfg) + self.old_cfg = old_cfg - except Exception: - pass # some OS's do not support termios, so ignore + except Exception: + pass # some OS's do not support termios, so ignore def __exit__(self, exc_type, exception, traceback): """If termios was avaialble, restore old settings.""" if self.old_cfg: - import termios - termios.tcsetattr( - self.stream.fileno(), termios.TCSADRAIN, self.old_cfg) + with background_safe(): # change it back even if backgrounded now + termios.tcsetattr(self.stream, termios.TCSADRAIN, self.old_cfg) class Unbuffered(object): @@ -426,45 +444,63 @@ class log_output(object): istreams = [in_pipe, stdin] if stdin else [in_pipe] log_file = self.log_file + + def handle_write(force_echo): + # Handle output from the with block process. + # If we arrive here it means that in_pipe was + # ready for reading : it should never happen that + # line is false-ish + line = in_pipe.readline() + if not line: + return (True, force_echo) # break while loop + + # find control characters and strip them. + controls = control.findall(line) + line = re.sub(control, '', line) + + # Echo to stdout if requested or forced + if echo or force_echo: + try: + if termios: + conf = termios.tcgetattr(sys.stdout) + tostop = conf[3] & termios.TOSTOP + else: + tostop = True + except Exception: + tostop = True + if not (tostop and _is_background_tty()): + sys.stdout.write(line) + sys.stdout.flush() + + # Stripped output to log file. + log_file.write(_strip(line)) + log_file.flush() + + if xon in controls: + force_echo = True + if xoff in controls: + force_echo = False + return (False, force_echo) + try: - with keyboard_input(stdin): + with _keyboard_input(stdin): while True: # No need to set any timeout for select.select # Wait until a key press or an event on in_pipe. rlist, _, _ = select.select(istreams, [], []) - # Allow user to toggle echo with 'v' key. # Currently ignores other chars. - if stdin in rlist: + # only read stdin if we're in the foreground + if stdin in rlist and not _is_background_tty(): if stdin.read(1) == 'v': echo = not echo - # Handle output from the with block process. if in_pipe in rlist: - # If we arrive here it means that in_pipe was - # ready for reading : it should never happen that - # line is false-ish - line = in_pipe.readline() - if not line: - break # EOF - - # find control characters and strip them. - controls = control.findall(line) - line = re.sub(control, '', line) - - # Echo to stdout if requested or forced - if echo or force_echo: - sys.stdout.write(line) - sys.stdout.flush() - - # Stripped output to log file. - log_file.write(_strip(line)) - log_file.flush() - - if xon in controls: - force_echo = True - if xoff in controls: - force_echo = False + br, fe = handle_write(force_echo) + force_echo = fe + if br: + break + except BaseException: tty.error("Exception occurred in writer daemon!") traceback.print_exc() |