hgext/pager.py
author Adrian Buehlmann <adrian@cadifra.com>
Tue, 07 Aug 2012 11:04:41 +0200
changeset 17732 93d97a212559
parent 17305 e66fa4d587dc
child 18717 fcc4b55876c3
permissions -rw-r--r--
exewrapper: adapt for legacy HackableMercurial We give up using CPython's PythonXX.lib import libraries (and Python.h), and now "manually" call the LoadLibrary() / GetProcAddress() Windows API's instead. If there is a "hg-python" subdirectory (the canonical directory name for HackableMercurial's private Python copy) next to the hg.exe, we load the pythonXX.dll from there (feeding an absolute path to LoadLibrary) and we set Py_SetPythonHome() to that directory, so that the Python libraries are used from there as well. If there is no "hg-python" subdir found next to the hg.exe, we do not feed an absolute path to LoadLibrary. This continues to allow to find a globally installed Python DLL, as before this change - that is, without having to edit, delete, rename, or configure anything. Note that the hg.exe built is still bound to a *specific* major version of the pythonXX.dll (e.g. python27.dll). What version it is, is inferred from the version of the python interpreter that was used when calling setup.py. For example C:\python27_x86\python.exe setup.py build_hgexe -i --compiler=mingw32 builds a hg.exe (using the mingw32 tool chain) bound to (x86) Python 2.7. And C:\python27_x86\python.exe setup.py build_hgexe -i builds the same using the Microsoft C compiler/linker. (Note that the Microsoft toolchain combined with x64 CPython can be used to build an x64 hg.exe.) setup.py is changed to write the name of the pythonlib into the generated header file "mercurial/hgpythonlib.h", which is #included by exewrapper.c. For a Python 2.7 build, it for example contains: #define HGPYTHONLIB "python27" exewrapper.c then uses HGPYTHONLIB for the name of the Python dll to load. We don't want to track mercurial/hgpythonlib.h, so we add it to .hgignore.

# 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.

To ignore global commands like :hg:`version` or :hg:`help`, you have
to specify them in your user configuration file.

The --pager=... option can also be used to control when the pager is
used. Use a boolean value like yes, no, on, off, or use auto for
normal behavior.
'''

import atexit, sys, os, signal, subprocess
from mercurial import commands, dispatch, util, extensions
from mercurial.i18n import _

testedwith = 'internal'

def _pagerfork(ui, p):
    if not util.safehasattr(os, 'fork'):
        sys.stdout = util.popen(p, 'wb')
        if ui._isatty(sys.stderr):
            sys.stderr = sys.stdout
        return
    fdin, fdout = os.pipe()
    pid = os.fork()
    if pid == 0:
        os.close(fdin)
        os.dup2(fdout, sys.stdout.fileno())
        if ui._isatty(sys.stderr):
            os.dup2(fdout, sys.stderr.fileno())
        os.close(fdout)
        return
    os.dup2(fdin, sys.stdin.fileno())
    os.close(fdin)
    os.close(fdout)
    try:
        os.execvp('/bin/sh', ['/bin/sh', '-c', p])
    except OSError, e:
        if e.errno == errno.ENOENT:
            # no /bin/sh, try executing the pager directly
            args = shlex.split(p)
            os.execvp(args[0], args)
        else:
            raise

def _pagersubprocess(ui, p):
    pager = subprocess.Popen(p, shell=True, bufsize=-1,
                             close_fds=util.closefds, stdin=subprocess.PIPE,
                             stdout=sys.stdout, stderr=sys.stderr)

    stdout = os.dup(sys.stdout.fileno())
    stderr = os.dup(sys.stderr.fileno())
    os.dup2(pager.stdin.fileno(), sys.stdout.fileno())
    if ui._isatty(sys.stderr):
        os.dup2(pager.stdin.fileno(), sys.stderr.fileno())

    @atexit.register
    def killpager():
        pager.stdin.close()
        os.dup2(stdout, sys.stdout.fileno())
        os.dup2(stderr, sys.stderr.fileno())
        pager.wait()

def _runpager(ui, p):
    # The subprocess module shipped with Python <= 2.4 is buggy (issue3533).
    # The compat version is buggy on Windows (issue3225), but has been shipping
    # with hg for a long time.  Preserve existing functionality.
    if sys.version_info >= (2, 5):
        _pagersubprocess(ui, p)
    else:
        _pagerfork(ui, p)

def uisetup(ui):
    if '--debugger' in sys.argv or not ui.formatted():
        return

    def pagecmd(orig, ui, options, cmd, cmdfunc):
        p = ui.config("pager", "pager", os.environ.get("PAGER"))

        if p:
            attend = ui.configlist('pager', 'attend', attended)
            auto = options['pager'] == 'auto'
            always = util.parsebool(options['pager'])
            if (always or auto and
                (cmd in attend or
                 (cmd not in ui.configlist('pager', 'ignore') and not attend))):
                ui.setconfig('ui', 'formatted', ui.formatted())
                ui.setconfig('ui', 'interactive', False)
                if util.safehasattr(signal, "SIGPIPE"):
                    signal.signal(signal.SIGPIPE, signal.SIG_DFL)
                _runpager(ui, p)
        return orig(ui, options, cmd, cmdfunc)

    extensions.wrapfunction(dispatch, '_runcommand', pagecmd)

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']