Mercurial > hg
view hgext/pager.py @ 30876:3a4c0905f357
util: always force line buffered stdout when stdout is a tty (BC)
pager replaced stdout with a line buffered version to work around glibc
deciding on a buffering strategy on the first write to stdout. This is going
to make my next patch hard, as replacing stdout will make tracking time
spent blocked on it more challenging.
Move the line buffering requirement to util.py, and remove it from pager.
This means that the abuse of ui.formatted=True and pager set to cat or equivalent
no longer results in a line-buffered output to a pipe, hence (BC), although
I don't expect anyone to be affected
author | Simon Farnsworth <simonfar@fb.com> |
---|---|
date | Fri, 03 Feb 2017 15:10:27 -0800 |
parents | aaa751585325 |
children | 253d5c0f3a2f |
line wrap: on
line source
# pager.py - display output using a pager # # Copyright 2008 David Soria Parra <dsp@php.net> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. # # To load the extension, add it to your configuration file: # # [extension] # pager = # # Run 'hg help pager' to get info on configuration. '''browse command output with an external pager To set the pager that should be used, set the application variable:: [pager] pager = less -FRX If no pager is set, the pager extensions uses the environment variable $PAGER. If neither pager.pager, nor $PAGER is set, no pager is used. You can disable the pager for certain commands by adding them to the pager.ignore list:: [pager] ignore = version, help, update You can also enable the pager only for certain commands using pager.attend. Below is the default list of commands to be paged:: [pager] attend = annotate, cat, diff, export, glog, log, qdiff Setting pager.attend to an empty value will cause all commands to be paged. If pager.attend is present, pager.ignore will be ignored. Lastly, you can enable and disable paging for individual commands with the attend-<command> option. This setting takes precedence over existing attend and ignore options and defaults:: [pager] attend-cat = false To ignore global commands like :hg:`version` or :hg:`help`, you have to specify them in your user configuration file. To control whether the pager is used at all for an individual command, you can use --pager=<value>:: - use as needed: `auto`. - require the pager: `yes` or `on`. - suppress the pager: `no` or `off` (any unrecognized value will also work). ''' from __future__ import absolute_import import atexit import os import signal import subprocess import sys from mercurial.i18n import _ from mercurial import ( cmdutil, commands, dispatch, encoding, extensions, util, ) # Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for # extensions which SHIP WITH MERCURIAL. Non-mainline extensions should # be specifying the version(s) of Mercurial they are tested with, or # leave the attribute unspecified. testedwith = 'ships-with-hg-core' def _runpager(ui, p): pager = subprocess.Popen(p, shell=True, bufsize=-1, close_fds=util.closefds, stdin=subprocess.PIPE, stdout=util.stdout, stderr=util.stderr) # back up original file descriptors stdoutfd = os.dup(util.stdout.fileno()) stderrfd = os.dup(util.stderr.fileno()) os.dup2(pager.stdin.fileno(), util.stdout.fileno()) if ui._isatty(util.stderr): os.dup2(pager.stdin.fileno(), util.stderr.fileno()) @atexit.register def killpager(): if util.safehasattr(signal, "SIGINT"): signal.signal(signal.SIGINT, signal.SIG_IGN) # restore original fds, closing pager.stdin copies in the process os.dup2(stdoutfd, util.stdout.fileno()) os.dup2(stderrfd, util.stderr.fileno()) pager.stdin.close() pager.wait() def uisetup(ui): class pagerui(ui.__class__): def _runpager(self, pagercmd): _runpager(self, pagercmd) ui.__class__ = pagerui def pagecmd(orig, ui, options, cmd, cmdfunc): p = ui.config("pager", "pager", encoding.environ.get("PAGER")) usepager = False always = util.parsebool(options['pager']) auto = options['pager'] == 'auto' if not p or '--debugger' in sys.argv or not ui.formatted(): pass elif always: usepager = True elif not auto: usepager = False else: attend = ui.configlist('pager', 'attend', attended) ignore = ui.configlist('pager', 'ignore') cmds, _ = cmdutil.findcmd(cmd, commands.table) for cmd in cmds: var = 'attend-%s' % cmd if ui.config('pager', var): usepager = ui.configbool('pager', var) break if (cmd in attend or (cmd not in ignore and not attend)): usepager = True break setattr(ui, 'pageractive', usepager) if usepager: ui.setconfig('ui', 'formatted', ui.formatted(), 'pager') ui.setconfig('ui', 'interactive', False, 'pager') ui._runpager(p) return orig(ui, options, cmd, cmdfunc) # Wrap dispatch._runcommand after color is loaded so color can see # ui.pageractive. Otherwise, if we loaded first, color's wrapped # dispatch._runcommand would run without having access to ui.pageractive. def afterloaded(loaded): extensions.wrapfunction(dispatch, '_runcommand', pagecmd) extensions.afterloaded('color', afterloaded) def extsetup(ui): commands.globalopts.append( ('', 'pager', 'auto', _("when to paginate (boolean, always, auto, or never)"), _('TYPE'))) attended = ['annotate', 'cat', 'diff', 'export', 'glog', 'log', 'qdiff']