Mercurial > hg
view mercurial/i18n.py @ 40626:87a872555e90
revlog: detect incomplete revlog reads
_readsegment() is supposed to return N bytes of revlog revision
data starting at a file offset. Surprisingly, its behavior before
this patch never verified that it actually read and returned N
bytes! Instead, it would perform the read(), then return whatever
data was available. And even more surprisingly, nothing in the
call chain appears to have been validating that it received all
the data it was expecting.
This behavior could lead to partial or incomplete revision chunks
being operated on. This could result in e.g. cached deltas being
applied against incomplete base revisions. The delta application
process would happily perform this operation. Only hash
verification would detect the corruption and save us.
This commit changes the behavior of raw revlog reading to validate
that we actually read() the number of bytes that were requested.
We will raise a more specific error faster, rather than possibly
have it go undetected or manifest later in the call stack, at
delta application or hash verification.
Differential Revision: https://phab.mercurial-scm.org/D5266
author | Gregory Szorc <gregory.szorc@gmail.com> |
---|---|
date | Tue, 13 Nov 2018 12:30:59 -0800 |
parents | dd83aafdb64a |
children | 2372284d9457 |
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# i18n.py - internationalization support for mercurial # # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import gettext as gettextmod import locale import os import sys from . import ( encoding, pycompat, ) # modelled after templater.templatepath: if getattr(sys, 'frozen', None) is not None: module = pycompat.sysexecutable else: module = pycompat.fsencode(__file__) _languages = None if (pycompat.iswindows and 'LANGUAGE' not in encoding.environ and 'LC_ALL' not in encoding.environ and 'LC_MESSAGES' not in encoding.environ and 'LANG' not in encoding.environ): # Try to detect UI language by "User Interface Language Management" API # if no locale variables are set. Note that locale.getdefaultlocale() # uses GetLocaleInfo(), which may be different from UI language. # (See http://msdn.microsoft.com/en-us/library/dd374098(v=VS.85).aspx ) try: import ctypes langid = ctypes.windll.kernel32.GetUserDefaultUILanguage() _languages = [locale.windows_locale[langid]] except (ImportError, AttributeError, KeyError): # ctypes not found or unknown langid pass _ugettext = None def setdatapath(datapath): datapath = pycompat.fsdecode(datapath) localedir = os.path.join(datapath, r'locale') t = gettextmod.translation(r'hg', localedir, _languages, fallback=True) global _ugettext try: _ugettext = t.ugettext except AttributeError: _ugettext = t.gettext _msgcache = {} # encoding: {message: translation} def gettext(message): """Translate message. The message is looked up in the catalog to get a Unicode string, which is encoded in the local encoding before being returned. Important: message is restricted to characters in the encoding given by sys.getdefaultencoding() which is most likely 'ascii'. """ # If message is None, t.ugettext will return u'None' as the # translation whereas our callers expect us to return None. if message is None or not _ugettext: return message cache = _msgcache.setdefault(encoding.encoding, {}) if message not in cache: if type(message) is pycompat.unicode: # goofy unicode docstrings in test paragraphs = message.split(u'\n\n') else: # should be ascii, but we have unicode docstrings in test, which # are converted to utf-8 bytes on Python 3. paragraphs = [p.decode("utf-8") for p in message.split('\n\n')] # Be careful not to translate the empty string -- it holds the # meta data of the .po file. u = u'\n\n'.join([p and _ugettext(p) or u'' for p in paragraphs]) try: # encoding.tolocal cannot be used since it will first try to # decode the Unicode string. Calling u.decode(enc) really # means u.encode(sys.getdefaultencoding()).decode(enc). Since # the Python encoding defaults to 'ascii', this fails if the # translated string use non-ASCII characters. encodingstr = pycompat.sysstr(encoding.encoding) cache[message] = u.encode(encodingstr, "replace") except LookupError: # An unknown encoding results in a LookupError. cache[message] = message return cache[message] def _plain(): if ('HGPLAIN' not in encoding.environ and 'HGPLAINEXCEPT' not in encoding.environ): return False exceptions = encoding.environ.get('HGPLAINEXCEPT', '').strip().split(',') return 'i18n' not in exceptions if _plain(): _ = lambda message: message else: _ = gettext