Mercurial > hg
view mercurial/pathutil.py @ 27015:341cb90ffd18
util: disable floating point stat times (issue4836)
Alternate fix for this issue which avoids putting extra function calls
and exception handling in the fast path.
For almost all purposes, integer timestamps are preferable to
Mercurial. It stores integer timestamps in the dirstate and would thus
like to avoid doing any float/int comparisons or conversions. We will
continue to have to deal with 1-second granularity on filesystems for
quite some time, so this won't significantly hinder our capabilities.
This has some impact on our file cache validation code in that it
lowers timestamp resolution. But as we still have to deal with
low-resolution filesystems, we're not relying on this anyway.
An alternate approach is to use stat[ST_MTIME], which is guaranteed to
be an integer. But since this support isn't already in our extension,
we can't depend on it being available without adding a hard Python->C
API dependency that's painful for people like yours truly who have
bisect regularly and people without compilers.
author | Matt Mackall <mpm@selenic.com> |
---|---|
date | Thu, 19 Nov 2015 13:21:24 -0600 |
parents | 56b2bcea2529 |
children | 6d29ce250a3d |
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from __future__ import absolute_import import errno import os import posixpath import stat from .i18n import _ from . import ( encoding, error, util, ) def _lowerclean(s): return encoding.hfsignoreclean(s.lower()) class pathauditor(object): '''ensure that a filesystem path contains no banned components. the following properties of a path are checked: - ends with a directory separator - under top-level .hg - starts at the root of a windows drive - contains ".." - traverses a symlink (e.g. a/symlink_here/b) - inside a nested repository (a callback can be used to approve some nested repositories, e.g., subrepositories) ''' def __init__(self, root, callback=None): self.audited = set() self.auditeddir = set() self.root = root self.callback = callback if os.path.lexists(root) and not util.checkcase(root): self.normcase = util.normcase else: self.normcase = lambda x: x def __call__(self, path): '''Check the relative path. path may contain a pattern (e.g. foodir/**.txt)''' path = util.localpath(path) normpath = self.normcase(path) if normpath in self.audited: return # AIX ignores "/" at end of path, others raise EISDIR. if util.endswithsep(path): raise error.Abort(_("path ends in directory separator: %s") % path) parts = util.splitpath(path) if (os.path.splitdrive(path)[0] or _lowerclean(parts[0]) in ('.hg', '.hg.', '') or os.pardir in parts): raise error.Abort(_("path contains illegal component: %s") % path) # Windows shortname aliases for p in parts: if "~" in p: first, last = p.split("~", 1) if last.isdigit() and first.upper() in ["HG", "HG8B6C"]: raise error.Abort(_("path contains illegal component: %s") % path) if '.hg' in _lowerclean(path): lparts = [_lowerclean(p.lower()) for p in parts] for p in '.hg', '.hg.': if p in lparts[1:]: pos = lparts.index(p) base = os.path.join(*parts[:pos]) raise error.Abort(_("path '%s' is inside nested repo %r") % (path, base)) normparts = util.splitpath(normpath) assert len(parts) == len(normparts) parts.pop() normparts.pop() prefixes = [] while parts: prefix = os.sep.join(parts) normprefix = os.sep.join(normparts) if normprefix in self.auditeddir: break curpath = os.path.join(self.root, prefix) try: st = os.lstat(curpath) except OSError as err: # EINVAL can be raised as invalid path syntax under win32. # They must be ignored for patterns can be checked too. if err.errno not in (errno.ENOENT, errno.ENOTDIR, errno.EINVAL): raise else: if stat.S_ISLNK(st.st_mode): raise error.Abort( _('path %r traverses symbolic link %r') % (path, prefix)) elif (stat.S_ISDIR(st.st_mode) and os.path.isdir(os.path.join(curpath, '.hg'))): if not self.callback or not self.callback(curpath): raise error.Abort(_("path '%s' is inside nested " "repo %r") % (path, prefix)) prefixes.append(normprefix) parts.pop() normparts.pop() self.audited.add(normpath) # only add prefixes to the cache after checking everything: we don't # want to add "foo/bar/baz" before checking if there's a "foo/.hg" self.auditeddir.update(prefixes) def check(self, path): try: self(path) return True except (OSError, error.Abort): return False def canonpath(root, cwd, myname, auditor=None): '''return the canonical path of myname, given cwd and root''' if util.endswithsep(root): rootsep = root else: rootsep = root + os.sep name = myname if not os.path.isabs(name): name = os.path.join(root, cwd, name) name = os.path.normpath(name) if auditor is None: auditor = pathauditor(root) if name != rootsep and name.startswith(rootsep): name = name[len(rootsep):] auditor(name) return util.pconvert(name) elif name == root: return '' else: # Determine whether `name' is in the hierarchy at or beneath `root', # by iterating name=dirname(name) until that causes no change (can't # check name == '/', because that doesn't work on windows). The list # `rel' holds the reversed list of components making up the relative # file name we want. rel = [] while True: try: s = util.samefile(name, root) except OSError: s = False if s: if not rel: # name was actually the same as root (maybe a symlink) return '' rel.reverse() name = os.path.join(*rel) auditor(name) return util.pconvert(name) dirname, basename = util.split(name) rel.append(basename) if dirname == name: break name = dirname # A common mistake is to use -R, but specify a file relative to the repo # instead of cwd. Detect that case, and provide a hint to the user. hint = None try: if cwd != root: canonpath(root, root, myname, auditor) hint = (_("consider using '--cwd %s'") % os.path.relpath(root, cwd)) except error.Abort: pass raise error.Abort(_("%s not under root '%s'") % (myname, root), hint=hint) def normasprefix(path): '''normalize the specified path as path prefix Returned value can be used safely for "p.startswith(prefix)", "p[len(prefix):]", and so on. For efficiency, this expects "path" argument to be already normalized by "os.path.normpath", "os.path.realpath", and so on. See also issue3033 for detail about need of this function. >>> normasprefix('/foo/bar').replace(os.sep, '/') '/foo/bar/' >>> normasprefix('/').replace(os.sep, '/') '/' ''' d, p = os.path.splitdrive(path) if len(p) != len(os.sep): return path + os.sep else: return path # forward two methods from posixpath that do what we need, but we'd # rather not let our internals know that we're thinking in posix terms # - instead we'll let them be oblivious. join = posixpath.join dirname = posixpath.dirname