# scmutil.py - Mercurial core utility functions

#

#  Copyright 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 i18n import _

from mercurial.node import nullrev

import util, error, osutil, revset, similar, encoding, phases, parsers

import pathutil

import match as matchmod

import os, errno, re, glob

if os.name == 'nt':

    import scmwindows as scmplatform

else:

    import scmposix as scmplatform

systemrcpath = scmplatform.systemrcpath

userrcpath = scmplatform.userrcpath

def nochangesfound(ui, repo, excluded=None):

    '''Report no changes for push/pull, excluded is None or a list of

    nodes excluded from the push/pull.

    '''

    secretlist = []

    if excluded:

        for n in excluded:

            if n not in repo:

                # discovery should not have included the filtered revision,

                # we have to explicitly exclude it until discovery is cleanup.

                continue

            ctx = repo[n]

            if ctx.phase() >= phases.secret and not ctx.extinct():

                secretlist.append(n)

    if secretlist:

        ui.status(_("no changes found (ignored %d secret changesets)\n")

                  % len(secretlist))

    else:

        ui.status(_("no changes found\n"))

def checknewlabel(repo, lbl, kind):

    # Do not use the "kind" parameter in ui output.

    # It makes strings difficult to translate.

    if lbl in ['tip', '.', 'null']:

        raise util.Abort(_("the name '%s' is reserved") % lbl)

    for c in (':', '\0', '\n', '\r'):

        if c in lbl:

            raise util.Abort(_("%r cannot be used in a name") % c)

    try:

        int(lbl)

        raise util.Abort(_("cannot use an integer as a name"))

    except ValueError:

        pass

def checkfilename(f):

    '''Check that the filename f is an acceptable filename for a tracked file'''

    if '\r' in f or '\n' in f:

        raise util.Abort(_("'\\n' and '\\r' disallowed in filenames: %r") % f)

def checkportable(ui, f):

    '''Check if filename f is portable and warn or abort depending on config'''

    checkfilename(f)

    abort, warn = checkportabilityalert(ui)

    if abort or warn:

        msg = util.checkwinfilename(f)

        if msg:

            msg = "%s: %r" % (msg, f)

            if abort:

                raise util.Abort(msg)

            ui.warn(_("warning: %s\n") % msg)

def checkportabilityalert(ui):

    '''check if the user's config requests nothing, a warning, or abort for

    non-portable filenames'''

    val = ui.config('ui', 'portablefilenames', 'warn')

    lval = val.lower()

    bval = util.parsebool(val)

    abort = os.name == 'nt' or lval == 'abort'

    warn = bval or lval == 'warn'

    if bval is None and not (warn or abort or lval == 'ignore'):

        raise error.ConfigError(

            _("ui.portablefilenames value is invalid ('%s')") % val)

    return abort, warn

class casecollisionauditor(object):

    def __init__(self, ui, abort, dirstate):

        self._ui = ui

        self._abort = abort

        allfiles = '\0'.join(dirstate._map)

        self._loweredfiles = set(encoding.lower(allfiles).split('\0'))

        self._dirstate = dirstate

        # The purpose of _newfiles is so that we don't complain about

        # case collisions if someone were to call this object with the

        # same filename twice.

        self._newfiles = set()

    def __call__(self, f):

        if f in self._newfiles:

            return

        fl = encoding.lower(f)

        if fl in self._loweredfiles and f not in self._dirstate:

            msg = _('possible case-folding collision for %s') % f

            if self._abort:

                raise util.Abort(msg)

            self._ui.warn(_("warning: %s\n") % msg)

        self._loweredfiles.add(fl)

        self._newfiles.add(f)

class abstractvfs(object):

    """Abstract base class; cannot be instantiated"""

    def __init__(self, *args, **kwargs):

        '''Prevent instantiation; don't call this from subclasses.'''

        raise NotImplementedError('attempted instantiating ' + str(type(self)))

    def tryread(self, path):

        '''gracefully return an empty string for missing files'''

        try:

            return self.read(path)

        except IOError, inst:

            if inst.errno != errno.ENOENT:

                raise

        return ""

    def open(self, path, mode="r", text=False, atomictemp=False):

        self.open = self.__call__

        return self.__call__(path, mode, text, atomictemp)

    def read(self, path):

        fp = self(path, 'rb')

        try:

            return fp.read()

        finally:

            fp.close()

    def write(self, path, data):

        fp = self(path, 'wb')

        try:

            return fp.write(data)

        finally:

            fp.close()

    def append(self, path, data):

        fp = self(path, 'ab')

        try:

            return fp.write(data)

        finally:

            fp.close()

    def exists(self, path=None):

        return os.path.exists(self.join(path))

    def fstat(self, fp):

        return util.fstat(fp)

    def isdir(self, path=None):

        return os.path.isdir(self.join(path))

    def isfile(self, path=None):

        return os.path.isfile(self.join(path))

    def islink(self, path=None):

        return os.path.islink(self.join(path))

    def lstat(self, path=None):

        return os.lstat(self.join(path))

    def makedir(self, path=None, notindexed=True):

        return util.makedir(self.join(path), notindexed)

    def makedirs(self, path=None, mode=None):

        return util.makedirs(self.join(path), mode)

    def mkdir(self, path=None):

        return os.mkdir(self.join(path))

    def readdir(self, path=None, stat=None, skip=None):

        return osutil.listdir(self.join(path), stat, skip)

    def rename(self, src, dst):

        return util.rename(self.join(src), self.join(dst))

    def readlink(self, path):

        return os.readlink(self.join(path))

    def setflags(self, path, l, x):

        return util.setflags(self.join(path), l, x)

    def stat(self, path=None):

        return os.stat(self.join(path))

    def unlink(self, path=None):

        return util.unlink(self.join(path))

    def utime(self, path=None, t=None):

        return os.utime(self.join(path), t)

class vfs(abstractvfs):

    '''Operate files relative to a base directory

    This class is used to hide the details of COW semantics and

    remote file access from higher level code.

    '''

    def __init__(self, base, audit=True, expandpath=False, realpath=False):

        if expandpath:

            base = util.expandpath(base)

        if realpath:

            base = os.path.realpath(base)

        self.base = base

        self._setmustaudit(audit)

        self.createmode = None

        self._trustnlink = None

    def _getmustaudit(self):

        return self._audit

    def _setmustaudit(self, onoff):

        self._audit = onoff

        if onoff:

            self.audit = pathutil.pathauditor(self.base)

        else:

            self.audit = util.always

    mustaudit = property(_getmustaudit, _setmustaudit)

    @util.propertycache

    def _cansymlink(self):

        return util.checklink(self.base)

    @util.propertycache

    def _chmod(self):

        return util.checkexec(self.base)

    def _fixfilemode(self, name):

        if self.createmode is None or not self._chmod:

            return

        os.chmod(name, self.createmode & 0666)

    def __call__(self, path, mode="r", text=False, atomictemp=False):

        if self._audit:

            r = util.checkosfilename(path)

            if r:

                raise util.Abort("%s: %r" % (r, path))

        self.audit(path)

        f = self.join(path)

        if not text and "b" not in mode:

            mode += "b" # for that other OS

        nlink = -1

        if mode not in ('r', 'rb'):

            dirname, basename = util.split(f)

            # If basename is empty, then the path is malformed because it points

            # to a directory. Let the posixfile() call below raise IOError.

            if basename:

                if atomictemp:

                    util.ensuredirs(dirname, self.createmode)

                    return util.atomictempfile(f, mode, self.createmode)

                try:

                    if 'w' in mode:

                        util.unlink(f)

                        nlink = 0

                    else:

                        # nlinks() may behave differently for files on Windows

                        # shares if the file is open.

                        fd = util.posixfile(f)

                        nlink = util.nlinks(f)

                        if nlink < 1:

                            nlink = 2 # force mktempcopy (issue1922)

                        fd.close()

                except (OSError, IOError), e:

                    if e.errno != errno.ENOENT:

                        raise

                    nlink = 0

                    util.ensuredirs(dirname, self.createmode)

                if nlink > 0:

                    if self._trustnlink is None:

                        self._trustnlink = nlink > 1 or util.checknlink(f)

                    if nlink > 1 or not self._trustnlink:

                        util.rename(util.mktempcopy(f), f)

        fp = util.posixfile(f, mode)

        if nlink == 0:

            self._fixfilemode(f)

        return fp

    def symlink(self, src, dst):

        self.audit(dst)

        linkname = self.join(dst)

        try:

            os.unlink(linkname)

        except OSError:

            pass

        util.ensuredirs(os.path.dirname(linkname), self.createmode)

        if self._cansymlink:

            try:

                os.symlink(src, linkname)

            except OSError, err:

                raise OSError(err.errno, _('could not symlink to %r: %s') %

                              (src, err.strerror), linkname)

        else:

            self.write(dst, src)

    def join(self, path):

        if path:

            return os.path.join(self.base, path)

        else:

            return self.base

opener = vfs

class auditvfs(object):

    def __init__(self, vfs):

        self.vfs = vfs

    def _getmustaudit(self):

        return self.vfs.mustaudit

    def _setmustaudit(self, onoff):

        self.vfs.mustaudit = onoff

    mustaudit = property(_getmustaudit, _setmustaudit)

class filtervfs(abstractvfs, auditvfs):

    '''Wrapper vfs for filtering filenames with a function.'''

    def __init__(self, vfs, filter):

        auditvfs.__init__(self, vfs)

        self._filter = filter

    def __call__(self, path, *args, **kwargs):

        return self.vfs(self._filter(path), *args, **kwargs)

    def join(self, path):

        if path:

            return self.vfs.join(self._filter(path))

        else:

            return self.vfs.join(path)

filteropener = filtervfs

class readonlyvfs(abstractvfs, auditvfs):

    '''Wrapper vfs preventing any writing.'''

    def __init__(self, vfs):

        auditvfs.__init__(self, vfs)

    def __call__(self, path, mode='r', *args, **kw):

        if mode not in ('r', 'rb'):

            raise util.Abort('this vfs is read only')

        return self.vfs(path, mode, *args, **kw)

def walkrepos(path, followsym=False, seen_dirs=None, recurse=False):

    '''yield every hg repository under path, always recursively.

    The recurse flag will only control recursion into repo working dirs'''

    def errhandler(err):

        if err.filename == path:

            raise err

    samestat = getattr(os.path, 'samestat', None)

    if followsym and samestat is not None:

        def adddir(dirlst, dirname):

            match = False

            dirstat = os.stat(dirname)

            for lstdirstat in dirlst:

                if samestat(dirstat, lstdirstat):

                    match = True

                    break

            if not match:

                dirlst.append(dirstat)

            return not match

    else:

        followsym = False

    if (seen_dirs is None) and followsym:

        seen_dirs = []

        adddir(seen_dirs, path)

    for root, dirs, files in os.walk(path, topdown=True, onerror=errhandler):

        dirs.sort()

        if '.hg' in dirs:

            yield root # found a repository

            qroot = os.path.join(root, '.hg', 'patches')

            if os.path.isdir(os.path.join(qroot, '.hg')):

                yield qroot # we have a patch queue repo here

            if recurse:

                # avoid recursing inside the .hg directory

                dirs.remove('.hg')

            else:

                dirs[:] = [] # don't descend further

        elif followsym:

            newdirs = []

            for d in dirs:

                fname = os.path.join(root, d)

                if adddir(seen_dirs, fname):

                    if os.path.islink(fname):

                        for hgname in walkrepos(fname, True, seen_dirs):

                            yield hgname

                    else:

                        newdirs.append(d)

            dirs[:] = newdirs

def osrcpath():

    '''return default os-specific hgrc search path'''

    path = systemrcpath()

    path.extend(userrcpath())

    path = [os.path.normpath(f) for f in path]

    return path

_rcpath = None

def rcpath():

    '''return hgrc search path. if env var HGRCPATH is set, use it.

    for each item in path, if directory, use files ending in .rc,

    else use item.

    make HGRCPATH empty to only look in .hg/hgrc of current repo.

    if no HGRCPATH, use default os-specific path.'''

    global _rcpath

    if _rcpath is None:

        if 'HGRCPATH' in os.environ:

            _rcpath = []

            for p in os.environ['HGRCPATH'].split(os.pathsep):

                if not p:

                    continue

                p = util.expandpath(p)

                if os.path.isdir(p):

                    for f, kind in osutil.listdir(p):

                        if f.endswith('.rc'):

                            _rcpath.append(os.path.join(p, f))

                else:

                    _rcpath.append(p)

        else:

            _rcpath = osrcpath()

    return _rcpath

def revsingle(repo, revspec, default='.'):

    if not revspec and revspec != 0:

        return repo[default]

    l = revrange(repo, [revspec])

    if len(l) < 1:

        raise util.Abort(_('empty revision set'))

    return repo[l[-1]]

def revpair(repo, revs):

    if not revs:

        return repo.dirstate.p1(), None

    l = revrange(repo, revs)

    if len(l) == 0:

        if revs:

            raise util.Abort(_('empty revision range'))

        return repo.dirstate.p1(), None

    if len(l) == 1 and len(revs) == 1 and _revrangesep not in revs[0]:

        return repo.lookup(l[0]), None

    return repo.lookup(l[0]), repo.lookup(l[-1])

_revrangesep = ':'

def revrange(repo, revs):

    """Yield revision as strings from a list of revision specifications."""

    def revfix(repo, val, defval):

        if not val and val != 0 and defval is not None:

            return defval

        return repo[val].rev()

    seen, l = set(), []

    for spec in revs:

        if l and not seen:

            seen = set(l)

        # attempt to parse old-style ranges first to deal with

        # things like old-tag which contain query metacharacters

        try:

            if isinstance(spec, int):

                seen.add(spec)

                l.append(spec)