Mercurial > hg
view hgext/win32text.py @ 23201:7e97bf6ee2d6
changelog: rework the delayupdate mechanism
The current way we use the 'delayupdate' mechanism is wrong. We call
'delayupdate' right after the transaction retrieval, then we call 'finalize'
right before calling 'tr.close()'. The 'finalize' call will -always- result in a
flush to disk, making the data available to all readers. But the 'tr.close()' may
be a no-op if the transaction is nested. This would result in data:
1) exposed to reader too early,
2) rolled back by other part of the transaction after such exposure
So we need to end up in a situation where we call 'finalize' a single time when
the transaction actually closes. For this purpose we need to be able to call
'delayupdate' and '_writepending' multiple times and 'finalize' once. This was
not possible with the previous state of the code.
This changeset refactors the code to makes this possible. We buffer data in memory
as much as possible and fall-back to writing to a ".a" file after the first call
to '_writepending'.
author | Pierre-Yves David <pierre-yves.david@fb.com> |
---|---|
date | Sat, 18 Oct 2014 01:12:18 -0700 |
parents | 23146e4d9cee |
children | 80c5b2666a96 |
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# win32text.py - LF <-> CRLF/CR translation utilities for Windows/Mac users # # Copyright 2005, 2007-2009 Matt Mackall <mpm@selenic.com> and others # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. '''perform automatic newline conversion (DEPRECATED) Deprecation: The win32text extension requires each user to configure the extension again and again for each clone since the configuration is not copied when cloning. We have therefore made the ``eol`` as an alternative. The ``eol`` uses a version controlled file for its configuration and each clone will therefore use the right settings from the start. To perform automatic newline conversion, use:: [extensions] win32text = [encode] ** = cleverencode: # or ** = macencode: [decode] ** = cleverdecode: # or ** = macdecode: If not doing conversion, to make sure you do not commit CRLF/CR by accident:: [hooks] pretxncommit.crlf = python:hgext.win32text.forbidcrlf # or pretxncommit.cr = python:hgext.win32text.forbidcr To do the same check on a server to prevent CRLF/CR from being pushed or pulled:: [hooks] pretxnchangegroup.crlf = python:hgext.win32text.forbidcrlf # or pretxnchangegroup.cr = python:hgext.win32text.forbidcr ''' from mercurial.i18n import _ from mercurial.node import short from mercurial import util import re testedwith = 'internal' # regexp for single LF without CR preceding. re_single_lf = re.compile('(^|[^\r])\n', re.MULTILINE) newlinestr = {'\r\n': 'CRLF', '\r': 'CR'} filterstr = {'\r\n': 'clever', '\r': 'mac'} def checknewline(s, newline, ui=None, repo=None, filename=None): # warn if already has 'newline' in repository. # it might cause unexpected eol conversion. # see issue 302: # http://mercurial.selenic.com/bts/issue302 if newline in s and ui and filename and repo: ui.warn(_('WARNING: %s already has %s line endings\n' 'and does not need EOL conversion by the win32text plugin.\n' 'Before your next commit, please reconsider your ' 'encode/decode settings in \nMercurial.ini or %s.\n') % (filename, newlinestr[newline], repo.join('hgrc'))) def dumbdecode(s, cmd, **kwargs): checknewline(s, '\r\n', **kwargs) # replace single LF to CRLF return re_single_lf.sub('\\1\r\n', s) def dumbencode(s, cmd): return s.replace('\r\n', '\n') def macdumbdecode(s, cmd, **kwargs): checknewline(s, '\r', **kwargs) return s.replace('\n', '\r') def macdumbencode(s, cmd): return s.replace('\r', '\n') def cleverdecode(s, cmd, **kwargs): if not util.binary(s): return dumbdecode(s, cmd, **kwargs) return s def cleverencode(s, cmd): if not util.binary(s): return dumbencode(s, cmd) return s def macdecode(s, cmd, **kwargs): if not util.binary(s): return macdumbdecode(s, cmd, **kwargs) return s def macencode(s, cmd): if not util.binary(s): return macdumbencode(s, cmd) return s _filters = { 'dumbdecode:': dumbdecode, 'dumbencode:': dumbencode, 'cleverdecode:': cleverdecode, 'cleverencode:': cleverencode, 'macdumbdecode:': macdumbdecode, 'macdumbencode:': macdumbencode, 'macdecode:': macdecode, 'macencode:': macencode, } def forbidnewline(ui, repo, hooktype, node, newline, **kwargs): halt = False seen = set() # we try to walk changesets in reverse order from newest to # oldest, so that if we see a file multiple times, we take the # newest version as canonical. this prevents us from blocking a # changegroup that contains an unacceptable commit followed later # by a commit that fixes the problem. tip = repo['tip'] for rev in xrange(len(repo) - 1, repo[node].rev() - 1, -1): c = repo[rev] for f in c.files(): if f in seen or f not in tip or f not in c: continue seen.add(f) data = c[f].data() if not util.binary(data) and newline in data: if not halt: ui.warn(_('attempt to commit or push text file(s) ' 'using %s line endings\n') % newlinestr[newline]) ui.warn(_('in %s: %s\n') % (short(c.node()), f)) halt = True if halt and hooktype == 'pretxnchangegroup': crlf = newlinestr[newline].lower() filter = filterstr[newline] ui.warn(_('\nTo prevent this mistake in your local repository,\n' 'add to Mercurial.ini or .hg/hgrc:\n' '\n' '[hooks]\n' 'pretxncommit.%s = python:hgext.win32text.forbid%s\n' '\n' 'and also consider adding:\n' '\n' '[extensions]\n' 'win32text =\n' '[encode]\n' '** = %sencode:\n' '[decode]\n' '** = %sdecode:\n') % (crlf, crlf, filter, filter)) return halt def forbidcrlf(ui, repo, hooktype, node, **kwargs): return forbidnewline(ui, repo, hooktype, node, '\r\n', **kwargs) def forbidcr(ui, repo, hooktype, node, **kwargs): return forbidnewline(ui, repo, hooktype, node, '\r', **kwargs) def reposetup(ui, repo): if not repo.local(): return for name, fn in _filters.iteritems(): repo.adddatafilter(name, fn) def extsetup(ui): if ui.configbool('win32text', 'warn', True): ui.warn(_("win32text is deprecated: " "http://mercurial.selenic.com/wiki/Win32TextExtension\n"))