hgext/blackbox.py
author Martin von Zweigbergk <martinvonz@google.com>
Sun, 09 Jul 2017 17:02:09 -0700
changeset 33379 7ddb2aa2b7af
parent 33361 66fe60d5f291
child 33436 9bb4decd43b0
permissions -rw-r--r--
match: express anypats(), not prefix(), in terms of the others When I added prefix() in 9789b4a7c595 (match: introduce boolean prefix() method, 2014-10-28), we already had always(), isexact(), and anypats(), so it made sense to write it in terms of them (a prefix matcher is one that isn't any of the other types). It's only now that I realize that it's much more natural to define prefix() explicitly (it's one that uses path: patterns, roughly speaking) and let anypats() be defined in terms of the others. Remember that these methods are all used for determining which fast paths are possible. anypats() simply means that no fast paths are possible (it could be called complex() instead). Further evidence is that rootfilesin:some/dir does not have any patterns, but it's still considered to be an anypats() matcher. That's because anypats() really just means that it's not a prefix() matcher (and not always() and not isexact()). This patch thus changes prefix() to return False by default and anypats() to return True only if the other three are False. Having anypats() be True by default also seems like a good thing, because it means forgetting to override it will lead only to performance bugs, not correctness bugs. Since the base class's implementation changes, we're also forced to update the subclasses. That change exposed and fixed a bug in the differencematcher: for example when both its two input matchers were prefix matchers, we would say that the result was also a prefix matcher, which is incorrect, because e.g "path:dir - path:dir/foo" no longer matches everything under "dir" (which is what prefix() means).

# blackbox.py - log repository events to a file for post-mortem debugging
#
# Copyright 2010 Nicolas Dumazet
# Copyright 2013 Facebook, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

"""log repository events to a blackbox for debugging

Logs event information to .hg/blackbox.log to help debug and diagnose problems.
The events that get logged can be configured via the blackbox.track config key.

Examples::

  [blackbox]
  track = *
  # dirty is *EXPENSIVE* (slow);
  # each log entry indicates `+` if the repository is dirty, like :hg:`id`.
  dirty = True
  # record the source of log messages
  logsource = True

  [blackbox]
  track = command, commandfinish, commandexception, exthook, pythonhook

  [blackbox]
  track = incoming

  [blackbox]
  # limit the size of a log file
  maxsize = 1.5 MB
  # rotate up to N log files when the current one gets too big
  maxfiles = 3

"""

from __future__ import absolute_import

import errno
import re

from mercurial.i18n import _
from mercurial.node import hex

from mercurial import (
    registrar,
    ui as uimod,
    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'

cmdtable = {}
command = registrar.command(cmdtable)

configtable = {}
configitem = registrar.configitem(configtable)

configitem('blackbox', 'dirty',
    default=False,
)
configitem('blackbox', 'maxsize',
    default='1 MB',
)
configitem('blackbox', 'logsource',
    default=False,
)

lastui = None

filehandles = {}

def _openlog(vfs):
    path = vfs.join('blackbox.log')
    if path in filehandles:
        return filehandles[path]
    filehandles[path] = fp = vfs('blackbox.log', 'a')
    return fp

def _closelog(vfs):
    path = vfs.join('blackbox.log')
    fp = filehandles[path]
    del filehandles[path]
    fp.close()

def wrapui(ui):
    class blackboxui(ui.__class__):
        def __init__(self, src=None):
            super(blackboxui, self).__init__(src)
            if src is None:
                self._partialinit()
            else:
                self._bbfp = getattr(src, '_bbfp', None)
                self._bbinlog = False
                self._bbrepo = getattr(src, '_bbrepo', None)
                self._bbvfs = getattr(src, '_bbvfs', None)

        def _partialinit(self):
            if util.safehasattr(self, '_bbvfs'):
                return
            self._bbfp = None
            self._bbinlog = False
            self._bbrepo = None
            self._bbvfs = None

        def copy(self):
            self._partialinit()
            return self.__class__(self)

        @util.propertycache
        def track(self):
            return self.configlist('blackbox', 'track', ['*'])

        def _openlogfile(self):
            def rotate(oldpath, newpath):
                try:
                    self._bbvfs.unlink(newpath)
                except OSError as err:
                    if err.errno != errno.ENOENT:
                        self.debug("warning: cannot remove '%s': %s\n" %
                                   (newpath, err.strerror))
                try:
                    if newpath:
                        self._bbvfs.rename(oldpath, newpath)
                except OSError as err:
                    if err.errno != errno.ENOENT:
                        self.debug("warning: cannot rename '%s' to '%s': %s\n" %
                                   (newpath, oldpath, err.strerror))

            fp = _openlog(self._bbvfs)
            maxsize = self.configbytes('blackbox', 'maxsize')
            if maxsize > 0:
                st = self._bbvfs.fstat(fp)
                if st.st_size >= maxsize:
                    path = fp.name
                    _closelog(self._bbvfs)
                    maxfiles = self.configint('blackbox', 'maxfiles', 7)
                    for i in xrange(maxfiles - 1, 1, -1):
                        rotate(oldpath='%s.%d' % (path, i - 1),
                               newpath='%s.%d' % (path, i))
                    rotate(oldpath=path,
                           newpath=maxfiles > 0 and path + '.1')
                    fp = _openlog(self._bbvfs)
            return fp

        def _bbwrite(self, fmt, *args):
            self._bbfp.write(fmt % args)
            self._bbfp.flush()

        def log(self, event, *msg, **opts):
            global lastui
            super(blackboxui, self).log(event, *msg, **opts)
            self._partialinit()

            if not '*' in self.track and not event in self.track:
                return

            if self._bbfp:
                ui = self
            elif self._bbvfs:
                try:
                    self._bbfp = self._openlogfile()
                except (IOError, OSError) as err:
                    self.debug('warning: cannot write to blackbox.log: %s\n' %
                               err.strerror)
                    del self._bbvfs
                    self._bbfp = None
                ui = self
            else:
                # certain ui instances exist outside the context of
                # a repo, so just default to the last blackbox that
                # was seen.
                ui = lastui

            if not ui or not ui._bbfp:
                return
            if not lastui or ui._bbrepo:
                lastui = ui
            if ui._bbinlog:
                # recursion guard
                return
            try:
                ui._bbinlog = True
                default = self.configdate('devel', 'default-date')
                date = util.datestr(default, '%Y/%m/%d %H:%M:%S')
                user = util.getuser()
                pid = '%d' % util.getpid()
                formattedmsg = msg[0] % msg[1:]
                rev = '(unknown)'
                changed = ''
                if ui._bbrepo:
                    ctx = ui._bbrepo[None]
                    parents = ctx.parents()
                    rev = ('+'.join([hex(p.node()) for p in parents]))
                    if (ui.configbool('blackbox', 'dirty') and
                        ctx.dirty(missing=True, merge=False, branch=False)):
                        changed = '+'
                if ui.configbool('blackbox', 'logsource'):
                    src = ' [%s]' % event
                else:
                    src = ''
                try:
                    ui._bbwrite('%s %s @%s%s (%s)%s> %s',
                        date, user, rev, changed, pid, src, formattedmsg)
                except IOError as err:
                    self.debug('warning: cannot write to blackbox.log: %s\n' %
                               err.strerror)
            finally:
                ui._bbinlog = False

        def setrepo(self, repo):
            self._bbfp = None
            self._bbinlog = False
            self._bbrepo = repo
            self._bbvfs = repo.vfs

    ui.__class__ = blackboxui
    uimod.ui = blackboxui

def uisetup(ui):
    wrapui(ui)

def reposetup(ui, repo):
    # During 'hg pull' a httppeer repo is created to represent the remote repo.
    # It doesn't have a .hg directory to put a blackbox in, so we don't do
    # the blackbox setup for it.
    if not repo.local():
        return

    if util.safehasattr(ui, 'setrepo'):
        ui.setrepo(repo)

@command('^blackbox',
    [('l', 'limit', 10, _('the number of events to show')),
    ],
    _('hg blackbox [OPTION]...'))
def blackbox(ui, repo, *revs, **opts):
    '''view the recent repository events
    '''

    if not repo.vfs.exists('blackbox.log'):
        return

    limit = opts.get('limit')
    fp = repo.vfs('blackbox.log', 'r')
    lines = fp.read().split('\n')

    count = 0
    output = []
    for line in reversed(lines):
        if count >= limit:
            break

        # count the commands by matching lines like: 2013/01/23 19:13:36 root>
        if re.match('^\d{4}/\d{2}/\d{2} \d{2}:\d{2}:\d{2} .*> .*', line):
            count += 1
        output.append(line)

    ui.status('\n'.join(reversed(output)))