view mercurial/scmposix.py @ 44425:5e3402a0b868

mergestate: determine if active without looking for state files on disk

I couldn't think of a reason that we need to check state files on disk
to determine if a merge is active. I could imagine them being for
there for detecting broken state files that would then be cleaned up
by some later command, but we always delete the entire `.hg/merge/`
tree, so that doesn't seem to be it.

The checks were added in 4e932dc5c113 (resolve: abort when not
applicable (BC), 2014-04-18). Perhaps there were needed for that and
then made obsolete by 6062593d8b06 (resolve: don't abort resolve -l
even when no merge is in progress, 2014-05-23).

The reason I want to delete the checks is that I think `ms =
mergestate.read(repo); ms.active() and ms.local` should be a valid
pattern, but it crashes when the merge state file is an empty file if
we consider mere presence of the file as "active".

Differential Revision: https://phab.mercurial-scm.org/D8118

from __future__ import absolute_import

import array
import errno
import fcntl
import os
import sys

from .pycompat import getattr
from . import (
    encoding,
    pycompat,
    util,
)

# BSD 'more' escapes ANSI color sequences by default. This can be disabled by
# $MORE variable, but there's no compatible option with Linux 'more'. Given
# OS X is widely used and most modern Unix systems would have 'less', setting
# 'less' as the default seems reasonable.
fallbackpager = b'less'


def _rcfiles(path):
    rcs = [os.path.join(path, b'hgrc')]
    rcdir = os.path.join(path, b'hgrc.d')
    try:
        rcs.extend(
            [
                os.path.join(rcdir, f)
                for f, kind in util.listdir(rcdir)
                if f.endswith(b".rc")
            ]
        )
    except OSError:
        pass
    return rcs


def systemrcpath():
    path = []
    if pycompat.sysplatform == b'plan9':
        root = b'lib/mercurial'
    else:
        root = b'etc/mercurial'
    # old mod_python does not set sys.argv
    if len(getattr(sys, 'argv', [])) > 0:
        p = os.path.dirname(os.path.dirname(pycompat.sysargv[0]))
        if p != b'/':
            path.extend(_rcfiles(os.path.join(p, root)))
    path.extend(_rcfiles(b'/' + root))
    return path


def userrcpath():
    if pycompat.sysplatform == b'plan9':
        return [encoding.environ[b'home'] + b'/lib/hgrc']
    elif pycompat.isdarwin:
        return [os.path.expanduser(b'~/.hgrc')]
    else:
        confighome = encoding.environ.get(b'XDG_CONFIG_HOME')
        if confighome is None or not os.path.isabs(confighome):
            confighome = os.path.expanduser(b'~/.config')

        return [
            os.path.expanduser(b'~/.hgrc'),
            os.path.join(confighome, b'hg', b'hgrc'),
        ]


def termsize(ui):
    try:
        import termios

        TIOCGWINSZ = termios.TIOCGWINSZ  # unavailable on IRIX (issue3449)
    except (AttributeError, ImportError):
        return 80, 24

    for dev in (ui.ferr, ui.fout, ui.fin):
        try:
            try:
                fd = dev.fileno()
            except AttributeError:
                continue
            if not os.isatty(fd):
                continue
            arri = fcntl.ioctl(fd, TIOCGWINSZ, b'\0' * 8)
            height, width = array.array('h', arri)[:2]
            if width > 0 and height > 0:
                return width, height
        except ValueError:
            pass
        except IOError as e:
            if e[0] == errno.EINVAL:  # pytype: disable=unsupported-operands
                pass
            else:
                raise
    return 80, 24