Mercurial > hg
view mercurial/fileset.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 | aebfc4c5c855 |
children | 1db5ae4b0dda |
line wrap: on
line source
# fileset.py - file set queries for mercurial # # Copyright 2010 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 errno import re from .i18n import _ from . import ( error, filesetlang, match as matchmod, merge, pycompat, registrar, scmutil, util, ) from .utils import ( stringutil, ) # common weight constants _WEIGHT_CHECK_FILENAME = filesetlang.WEIGHT_CHECK_FILENAME _WEIGHT_READ_CONTENTS = filesetlang.WEIGHT_READ_CONTENTS _WEIGHT_STATUS = filesetlang.WEIGHT_STATUS _WEIGHT_STATUS_THOROUGH = filesetlang.WEIGHT_STATUS_THOROUGH # helpers for processing parsed tree getsymbol = filesetlang.getsymbol getstring = filesetlang.getstring _getkindpat = filesetlang.getkindpat getpattern = filesetlang.getpattern getargs = filesetlang.getargs def getmatch(mctx, x): if not x: raise error.ParseError(_("missing argument")) return methods[x[0]](mctx, *x[1:]) def getmatchwithstatus(mctx, x, hint): keys = set(getstring(hint, 'status hint must be a string').split()) return getmatch(mctx.withstatus(keys), x) def stringmatch(mctx, x): return mctx.matcher([x]) def kindpatmatch(mctx, x, y): return stringmatch(mctx, _getkindpat(x, y, matchmod.allpatternkinds, _("pattern must be a string"))) def patternsmatch(mctx, *xs): allkinds = matchmod.allpatternkinds patterns = [getpattern(x, allkinds, _("pattern must be a string")) for x in xs] return mctx.matcher(patterns) def andmatch(mctx, x, y): xm = getmatch(mctx, x) ym = getmatch(mctx.narrowed(xm), y) return matchmod.intersectmatchers(xm, ym) def ormatch(mctx, *xs): ms = [getmatch(mctx, x) for x in xs] return matchmod.unionmatcher(ms) def notmatch(mctx, x): m = getmatch(mctx, x) return mctx.predicate(lambda f: not m(f), predrepr=('<not %r>', m)) def minusmatch(mctx, x, y): xm = getmatch(mctx, x) ym = getmatch(mctx.narrowed(xm), y) return matchmod.differencematcher(xm, ym) def listmatch(mctx, *xs): raise error.ParseError(_("can't use a list in this context"), hint=_('see \'hg help "filesets.x or y"\'')) def func(mctx, a, b): funcname = getsymbol(a) if funcname in symbols: return symbols[funcname](mctx, b) keep = lambda fn: getattr(fn, '__doc__', None) is not None syms = [s for (s, fn) in symbols.items() if keep(fn)] raise error.UnknownIdentifier(funcname, syms) # symbols are callable like: # fun(mctx, x) # with: # mctx - current matchctx instance # x - argument in tree form symbols = filesetlang.symbols predicate = registrar.filesetpredicate(symbols) @predicate('modified()', callstatus=True, weight=_WEIGHT_STATUS) def modified(mctx, x): """File that is modified according to :hg:`status`. """ # i18n: "modified" is a keyword getargs(x, 0, 0, _("modified takes no arguments")) s = set(mctx.status().modified) return mctx.predicate(s.__contains__, predrepr='modified') @predicate('added()', callstatus=True, weight=_WEIGHT_STATUS) def added(mctx, x): """File that is added according to :hg:`status`. """ # i18n: "added" is a keyword getargs(x, 0, 0, _("added takes no arguments")) s = set(mctx.status().added) return mctx.predicate(s.__contains__, predrepr='added') @predicate('removed()', callstatus=True, weight=_WEIGHT_STATUS) def removed(mctx, x): """File that is removed according to :hg:`status`. """ # i18n: "removed" is a keyword getargs(x, 0, 0, _("removed takes no arguments")) s = set(mctx.status().removed) return mctx.predicate(s.__contains__, predrepr='removed') @predicate('deleted()', callstatus=True, weight=_WEIGHT_STATUS) def deleted(mctx, x): """Alias for ``missing()``. """ # i18n: "deleted" is a keyword getargs(x, 0, 0, _("deleted takes no arguments")) s = set(mctx.status().deleted) return mctx.predicate(s.__contains__, predrepr='deleted') @predicate('missing()', callstatus=True, weight=_WEIGHT_STATUS) def missing(mctx, x): """File that is missing according to :hg:`status`. """ # i18n: "missing" is a keyword getargs(x, 0, 0, _("missing takes no arguments")) s = set(mctx.status().deleted) return mctx.predicate(s.__contains__, predrepr='deleted') @predicate('unknown()', callstatus=True, weight=_WEIGHT_STATUS_THOROUGH) def unknown(mctx, x): """File that is unknown according to :hg:`status`.""" # i18n: "unknown" is a keyword getargs(x, 0, 0, _("unknown takes no arguments")) s = set(mctx.status().unknown) return mctx.predicate(s.__contains__, predrepr='unknown') @predicate('ignored()', callstatus=True, weight=_WEIGHT_STATUS_THOROUGH) def ignored(mctx, x): """File that is ignored according to :hg:`status`.""" # i18n: "ignored" is a keyword getargs(x, 0, 0, _("ignored takes no arguments")) s = set(mctx.status().ignored) return mctx.predicate(s.__contains__, predrepr='ignored') @predicate('clean()', callstatus=True, weight=_WEIGHT_STATUS) def clean(mctx, x): """File that is clean according to :hg:`status`. """ # i18n: "clean" is a keyword getargs(x, 0, 0, _("clean takes no arguments")) s = set(mctx.status().clean) return mctx.predicate(s.__contains__, predrepr='clean') @predicate('tracked()') def tracked(mctx, x): """File that is under Mercurial control.""" # i18n: "tracked" is a keyword getargs(x, 0, 0, _("tracked takes no arguments")) return mctx.predicate(mctx.ctx.__contains__, predrepr='tracked') @predicate('binary()', weight=_WEIGHT_READ_CONTENTS) def binary(mctx, x): """File that appears to be binary (contains NUL bytes). """ # i18n: "binary" is a keyword getargs(x, 0, 0, _("binary takes no arguments")) return mctx.fpredicate(lambda fctx: fctx.isbinary(), predrepr='binary', cache=True) @predicate('exec()') def exec_(mctx, x): """File that is marked as executable. """ # i18n: "exec" is a keyword getargs(x, 0, 0, _("exec takes no arguments")) ctx = mctx.ctx return mctx.predicate(lambda f: ctx.flags(f) == 'x', predrepr='exec') @predicate('symlink()') def symlink(mctx, x): """File that is marked as a symlink. """ # i18n: "symlink" is a keyword getargs(x, 0, 0, _("symlink takes no arguments")) ctx = mctx.ctx return mctx.predicate(lambda f: ctx.flags(f) == 'l', predrepr='symlink') @predicate('resolved()', weight=_WEIGHT_STATUS) def resolved(mctx, x): """File that is marked resolved according to :hg:`resolve -l`. """ # i18n: "resolved" is a keyword getargs(x, 0, 0, _("resolved takes no arguments")) if mctx.ctx.rev() is not None: return mctx.never() ms = merge.mergestate.read(mctx.ctx.repo()) return mctx.predicate(lambda f: f in ms and ms[f] == 'r', predrepr='resolved') @predicate('unresolved()', weight=_WEIGHT_STATUS) def unresolved(mctx, x): """File that is marked unresolved according to :hg:`resolve -l`. """ # i18n: "unresolved" is a keyword getargs(x, 0, 0, _("unresolved takes no arguments")) if mctx.ctx.rev() is not None: return mctx.never() ms = merge.mergestate.read(mctx.ctx.repo()) return mctx.predicate(lambda f: f in ms and ms[f] == 'u', predrepr='unresolved') @predicate('hgignore()', weight=_WEIGHT_STATUS) def hgignore(mctx, x): """File that matches the active .hgignore pattern. """ # i18n: "hgignore" is a keyword getargs(x, 0, 0, _("hgignore takes no arguments")) return mctx.ctx.repo().dirstate._ignore @predicate('portable()', weight=_WEIGHT_CHECK_FILENAME) def portable(mctx, x): """File that has a portable name. (This doesn't include filenames with case collisions.) """ # i18n: "portable" is a keyword getargs(x, 0, 0, _("portable takes no arguments")) return mctx.predicate(lambda f: util.checkwinfilename(f) is None, predrepr='portable') @predicate('grep(regex)', weight=_WEIGHT_READ_CONTENTS) def grep(mctx, x): """File contains the given regular expression. """ try: # i18n: "grep" is a keyword r = re.compile(getstring(x, _("grep requires a pattern"))) except re.error as e: raise error.ParseError(_('invalid match pattern: %s') % stringutil.forcebytestr(e)) return mctx.fpredicate(lambda fctx: r.search(fctx.data()), predrepr=('grep(%r)', r.pattern), cache=True) def _sizetomax(s): try: s = s.strip().lower() for k, v in util._sizeunits: if s.endswith(k): # max(4k) = 5k - 1, max(4.5k) = 4.6k - 1 n = s[:-len(k)] inc = 1.0 if "." in n: inc /= 10 ** len(n.split(".")[1]) return int((float(n) + inc) * v) - 1 # no extension, this is a precise value return int(s) except ValueError: raise error.ParseError(_("couldn't parse size: %s") % s) def sizematcher(expr): """Return a function(size) -> bool from the ``size()`` expression""" expr = expr.strip() if '-' in expr: # do we have a range? a, b = expr.split('-', 1) a = util.sizetoint(a) b = util.sizetoint(b) return lambda x: x >= a and x <= b elif expr.startswith("<="): a = util.sizetoint(expr[2:]) return lambda x: x <= a elif expr.startswith("<"): a = util.sizetoint(expr[1:]) return lambda x: x < a elif expr.startswith(">="): a = util.sizetoint(expr[2:]) return lambda x: x >= a elif expr.startswith(">"): a = util.sizetoint(expr[1:]) return lambda x: x > a else: a = util.sizetoint(expr) b = _sizetomax(expr) return lambda x: x >= a and x <= b @predicate('size(expression)', weight=_WEIGHT_STATUS) def size(mctx, x): """File size matches the given expression. Examples: - size('1k') - files from 1024 to 2047 bytes - size('< 20k') - files less than 20480 bytes - size('>= .5MB') - files at least 524288 bytes - size('4k - 1MB') - files from 4096 bytes to 1048576 bytes """ # i18n: "size" is a keyword expr = getstring(x, _("size requires an expression")) m = sizematcher(expr) return mctx.fpredicate(lambda fctx: m(fctx.size()), predrepr=('size(%r)', expr), cache=True) @predicate('encoding(name)', weight=_WEIGHT_READ_CONTENTS) def encoding(mctx, x): """File can be successfully decoded with the given character encoding. May not be useful for encodings other than ASCII and UTF-8. """ # i18n: "encoding" is a keyword enc = getstring(x, _("encoding requires an encoding name")) def encp(fctx): d = fctx.data() try: d.decode(pycompat.sysstr(enc)) return True except LookupError: raise error.Abort(_("unknown encoding '%s'") % enc) except UnicodeDecodeError: return False return mctx.fpredicate(encp, predrepr=('encoding(%r)', enc), cache=True) @predicate('eol(style)', weight=_WEIGHT_READ_CONTENTS) def eol(mctx, x): """File contains newlines of the given style (dos, unix, mac). Binary files are excluded, files with mixed line endings match multiple styles. """ # i18n: "eol" is a keyword enc = getstring(x, _("eol requires a style name")) def eolp(fctx): if fctx.isbinary(): return False d = fctx.data() if (enc == 'dos' or enc == 'win') and '\r\n' in d: return True elif enc == 'unix' and re.search('(?<!\r)\n', d): return True elif enc == 'mac' and re.search('\r(?!\n)', d): return True return False return mctx.fpredicate(eolp, predrepr=('eol(%r)', enc), cache=True) @predicate('copied()') def copied(mctx, x): """File that is recorded as being copied. """ # i18n: "copied" is a keyword getargs(x, 0, 0, _("copied takes no arguments")) def copiedp(fctx): p = fctx.parents() return p and p[0].path() != fctx.path() return mctx.fpredicate(copiedp, predrepr='copied', cache=True) @predicate('revs(revs, pattern)', weight=_WEIGHT_STATUS) def revs(mctx, x): """Evaluate set in the specified revisions. If the revset match multiple revs, this will return file matching pattern in any of the revision. """ # i18n: "revs" is a keyword r, x = getargs(x, 2, 2, _("revs takes two arguments")) # i18n: "revs" is a keyword revspec = getstring(r, _("first argument to revs must be a revision")) repo = mctx.ctx.repo() revs = scmutil.revrange(repo, [revspec]) matchers = [] for r in revs: ctx = repo[r] mc = mctx.switch(ctx.p1(), ctx) matchers.append(getmatch(mc, x)) if not matchers: return mctx.never() if len(matchers) == 1: return matchers[0] return matchmod.unionmatcher(matchers) @predicate('status(base, rev, pattern)', weight=_WEIGHT_STATUS) def status(mctx, x): """Evaluate predicate using status change between ``base`` and ``rev``. Examples: - ``status(3, 7, added())`` - matches files added from "3" to "7" """ repo = mctx.ctx.repo() # i18n: "status" is a keyword b, r, x = getargs(x, 3, 3, _("status takes three arguments")) # i18n: "status" is a keyword baseerr = _("first argument to status must be a revision") baserevspec = getstring(b, baseerr) if not baserevspec: raise error.ParseError(baseerr) reverr = _("second argument to status must be a revision") revspec = getstring(r, reverr) if not revspec: raise error.ParseError(reverr) basectx, ctx = scmutil.revpair(repo, [baserevspec, revspec]) mc = mctx.switch(basectx, ctx) return getmatch(mc, x) @predicate('subrepo([pattern])') def subrepo(mctx, x): """Subrepositories whose paths match the given pattern. """ # i18n: "subrepo" is a keyword getargs(x, 0, 1, _("subrepo takes at most one argument")) ctx = mctx.ctx sstate = ctx.substate if x: pat = getpattern(x, matchmod.allpatternkinds, # i18n: "subrepo" is a keyword _("subrepo requires a pattern or no arguments")) fast = not matchmod.patkind(pat) if fast: def m(s): return (s == pat) else: m = matchmod.match(ctx.repo().root, '', [pat], ctx=ctx) return mctx.predicate(lambda f: f in sstate and m(f), predrepr=('subrepo(%r)', pat)) else: return mctx.predicate(sstate.__contains__, predrepr='subrepo') methods = { 'withstatus': getmatchwithstatus, 'string': stringmatch, 'symbol': stringmatch, 'kindpat': kindpatmatch, 'patterns': patternsmatch, 'and': andmatch, 'or': ormatch, 'minus': minusmatch, 'list': listmatch, 'not': notmatch, 'func': func, } class matchctx(object): def __init__(self, basectx, ctx, badfn=None): self._basectx = basectx self.ctx = ctx self._badfn = badfn self._match = None self._status = None def narrowed(self, match): """Create matchctx for a sub-tree narrowed by the given matcher""" mctx = matchctx(self._basectx, self.ctx, self._badfn) mctx._match = match # leave wider status which we don't have to care mctx._status = self._status return mctx def switch(self, basectx, ctx): mctx = matchctx(basectx, ctx, self._badfn) mctx._match = self._match return mctx def withstatus(self, keys): """Create matchctx which has precomputed status specified by the keys""" mctx = matchctx(self._basectx, self.ctx, self._badfn) mctx._match = self._match mctx._buildstatus(keys) return mctx def _buildstatus(self, keys): self._status = self._basectx.status(self.ctx, self._match, listignored='ignored' in keys, listclean='clean' in keys, listunknown='unknown' in keys) def status(self): return self._status def matcher(self, patterns): return self.ctx.match(patterns, badfn=self._badfn) def predicate(self, predfn, predrepr=None, cache=False): """Create a matcher to select files by predfn(filename)""" if cache: predfn = util.cachefunc(predfn) repo = self.ctx.repo() return matchmod.predicatematcher(repo.root, repo.getcwd(), predfn, predrepr=predrepr, badfn=self._badfn) def fpredicate(self, predfn, predrepr=None, cache=False): """Create a matcher to select files by predfn(fctx) at the current revision Missing files are ignored. """ ctx = self.ctx if ctx.rev() is None: def fctxpredfn(f): try: fctx = ctx[f] except error.LookupError: return False try: fctx.audit() except error.Abort: return False try: return predfn(fctx) except (IOError, OSError) as e: # open()-ing a directory fails with EACCES on Windows if e.errno in (errno.ENOENT, errno.EACCES, errno.ENOTDIR, errno.EISDIR): return False raise else: def fctxpredfn(f): try: fctx = ctx[f] except error.LookupError: return False return predfn(fctx) return self.predicate(fctxpredfn, predrepr=predrepr, cache=cache) def never(self): """Create a matcher to select nothing""" repo = self.ctx.repo() return matchmod.nevermatcher(repo.root, repo.getcwd(), badfn=self._badfn) def match(ctx, expr, badfn=None): """Create a matcher for a single fileset expression""" tree = filesetlang.parse(expr) tree = filesetlang.analyze(tree) tree = filesetlang.optimize(tree) mctx = matchctx(ctx.p1(), ctx, badfn=badfn) return getmatch(mctx, tree) def loadpredicate(ui, extname, registrarobj): """Load fileset predicates from specified registrarobj """ for name, func in registrarobj._table.iteritems(): symbols[name] = func # tell hggettext to extract docstrings from these functions: i18nfunctions = symbols.values()