~bzr-pqm/bzr/bzr.dev

# Copyright (C) 2005 Canonical Ltd

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation; either version 2 of the License, or

# (at your option) any later version.

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

import sys

import os

import bzrlib

from bzrlib.trace import mutter, note

from bzrlib.osutils import isdir, quotefn, compact_date, rand_bytes, \

     splitpath, \

     sha_file, appendpath, file_kind

from bzrlib.errors import BzrError, InvalidRevisionNumber, InvalidRevisionId, \

     DivergedBranches, NotBranchError

from bzrlib.textui import show_status

from bzrlib.revision import Revision

from bzrlib.delta import compare_trees

from bzrlib.tree import EmptyTree, RevisionTree

import bzrlib.xml

import bzrlib.ui

BZR_BRANCH_FORMAT = "Bazaar-NG branch, format 0.0.4\n"

## TODO: Maybe include checks for common corruption of newlines, etc?

# TODO: Some operations like log might retrieve the same revisions

# repeatedly to calculate deltas.  We could perhaps have a weakref

# cache in memory to make this faster.

# TODO: please move the revision-string syntax stuff out of the branch

# object; it's clutter

def find_branch(f, **args):

    from bzrlib.transport import transport

    from bzrlib.local_transport import LocalTransport

    t = transport(f)

    # FIXME: This is a hack around transport so that

    #        We can search the local directories for

    #        a branch root.

    if args.has_key('init') and args['init']:

        # Don't search if we are init-ing

        return Branch(t, **args)

    if isinstance(t, LocalTransport):

        root = find_branch_root(f)

        if root != f:

            t = transport(root)

    return Branch(t, **args)

def _relpath(base, path):

    """Return path relative to base, or raise exception.

    The path may be either an absolute path or a path relative to the

    current working directory.

    Lifted out of Branch.relpath for ease of testing.

    os.path.commonprefix (python2.4) has a bad bug that it works just

    on string prefixes, assuming that '/u' is a prefix of '/u2'.  This

    avoids that problem."""

    rp = os.path.abspath(path)

    s = []

    head = rp

    while len(head) >= len(base):

        if head == base:

            break

        head, tail = os.path.split(head)

        if tail:

            s.insert(0, tail)

    else:

        raise NotBranchError("path %r is not within branch %r" % (rp, base))

    return os.sep.join(s)

def find_branch_root(f=None):

    """Find the branch root enclosing f, or pwd.

    f may be a filename or a URL.

    It is not necessary that f exists.

    Basically we keep looking up until we find the control directory or

    run into the root.  If there isn't one, raises NotBranchError.

    """

    if f == None:

        f = os.getcwd()

    else:

        f = os.path.realpath(f)

    if not os.path.exists(f):

        raise BzrError('%r does not exist' % f)

    orig_f = f

    while True:

        if os.path.exists(os.path.join(f, bzrlib.BZRDIR)):

            return f

        head, tail = os.path.split(f)

        if head == f:

            # reached the root, whatever that may be

            raise NotBranchError('%s is not in a branch' % orig_f)

        f = head

######################################################################

# branch objects

class Branch(object):

    """Branch holding a history of revisions.

    base

        Base directory of the branch.

    _lock_mode

        None, or 'r' or 'w'

    _lock_count

        If _lock_mode is true, a positive count of the number of times the

        lock has been taken.

    _lock

        Lock object from bzrlib.lock.

    """

    base = None

    _lock_mode = None

    _lock_count = None

    _lock = None

    cache_root = None

    # Map some sort of prefix into a namespace

    # stuff like "revno:10", "revid:", etc.

    # This should match a prefix with a function which accepts

    REVISION_NAMESPACES = {}

    def __init__(self, transport, init=False):

        """Create new branch object at a particular location.

        transport -- A Transport object, defining how to access files.

                (If a string, transport.transport() will be used to

                create a Transport object)

        init -- If True, create new control files in a previously

             unversioned directory.  If False, the branch must already

             be versioned.

        In the test suite, creation of new trees is tested using the

        `ScratchBranch` class.

        """

        if isinstance(transport, basestring):

            from transport import transport as get_transport

            transport = get_transport(transport)

        self._transport = transport

        if init:

            self._make_control()

        self._check_format()

    def __str__(self):

        return '%s(%r)' % (self.__class__.__name__, self._transport.base)

    __repr__ = __str__

    def __del__(self):

        if self._lock_mode or self._lock:

            from bzrlib.warnings import warn

            warn("branch %r was not explicitly unlocked" % self)

            self._lock.unlock()

        # TODO: It might be best to do this somewhere else,

        # but it is nice for a Branch object to automatically

        # cache it's information.

        # Alternatively, we could have the Transport objects cache requests

        # See the earlier discussion about how major objects (like Branch)

        # should never expect their __del__ function to run.

        if self.cache_root is not None:

            #from warnings import warn

            #warn("branch %r auto-cleanup of cache files" % self)

            try:

                import shutil

                shutil.rmtree(self.cache_root)

            except:

                pass

            self.cache_root = None

    def _get_base(self):

        if self._transport:

            return self._transport.base

        return None

    base = property(_get_base)

    def lock_write(self):

        # TODO: Upgrade locking to support using a Transport,

        # and potentially a remote locking protocol

        if self._lock_mode:

            if self._lock_mode != 'w':

                from bzrlib.errors import LockError

                raise LockError("can't upgrade to a write lock from %r" %

                                self._lock_mode)

            self._lock_count += 1

        else:

            self._lock = self._transport.lock_write(

                    self._rel_controlfilename('branch-lock'))

            self._lock_mode = 'w'

            self._lock_count = 1

    def lock_read(self):

        if self._lock_mode:

            assert self._lock_mode in ('r', 'w'), \

                   "invalid lock mode %r" % self._lock_mode

            self._lock_count += 1

        else:

            self._lock = self._transport.lock_read(

                    self._rel_controlfilename('branch-lock'))

            self._lock_mode = 'r'

            self._lock_count = 1

    def unlock(self):

        if not self._lock_mode:

            from bzrlib.errors import LockError

            raise LockError('branch %r is not locked' % (self))

        if self._lock_count > 1:

            self._lock_count -= 1

        else:

            self._lock.unlock()

            self._lock = None

            self._lock_mode = self._lock_count = None

    def abspath(self, name):

        """Return absolute filename for something in the branch"""

        return self._transport.abspath(name)

    def relpath(self, path):

        """Return path relative to this branch of something inside it.

        Raises an error if path is not in this branch."""

        return self._transport.relpath(path)

    def _rel_controlfilename(self, file_or_path):

        if isinstance(file_or_path, basestring):

            file_or_path = [file_or_path]

        return [bzrlib.BZRDIR] + file_or_path

    def controlfilename(self, file_or_path):

        """Return location relative to branch."""

        return self._transport.abspath(self._rel_controlfilename(file_or_path))

    def controlfile(self, file_or_path, mode='r'):

        """Open a control file for this branch.

        There are two classes of file in the control directory: text

        and binary.  binary files are untranslated byte streams.  Text

        control files are stored with Unix newlines and in UTF-8, even

        if the platform or locale defaults are different.

        Controlfiles should almost never be opened in write mode but

        rather should be atomically copied and replaced using atomicfile.

        """

        import codecs

        relpath = self._rel_controlfilename(file_or_path)

        #TODO: codecs.open() buffers linewise, so it was overloaded with

        # a much larger buffer, do we need to do the same for getreader/getwriter?

        if mode == 'rb': 

            return self._transport.get(relpath)

        elif mode == 'wb':

            raise BzrError("Branch.controlfile(mode='wb') is not supported, use put_controlfiles")

        elif mode == 'r':

            return codecs.getreader('utf-8')(self._transport.get(relpath), errors='replace')

        elif mode == 'w':

            raise BzrError("Branch.controlfile(mode='w') is not supported, use put_controlfiles")

        else:

            raise BzrError("invalid controlfile mode %r" % mode)

    def put_controlfile(self, path, f, encode=True):

        """Write an entry as a controlfile.

        :param path: The path to put the file, relative to the .bzr control

                     directory

        :param f: A file-like or string object whose contents should be copied.

        :param encode:  If true, encode the contents as utf-8

        """

        self.put_controlfiles([(path, f)], encode=encode)

    def put_controlfiles(self, files, encode=True):

        """Write several entries as controlfiles.

        :param files: A list of [(path, file)] pairs, where the path is the directory

                      underneath the bzr control directory

        :param encode:  If true, encode the contents as utf-8

        """

        import codecs

        ctrl_files = []

        for path, f in files:

            if encode:

                if isinstance(f, basestring):

                    f = f.encode('utf-8', 'replace')

                else:

                    f = codecs.getwriter('utf-8')(f, errors='replace')

            path = self._rel_controlfilename(path)

            ctrl_files.append((path, f))

        self._transport.put_multi(ctrl_files)

    def _make_control(self):

        from bzrlib.inventory import Inventory

        from cStringIO import StringIO

        # Create an empty inventory

        sio = StringIO()

        # if we want per-tree root ids then this is the place to set

        # them; they're not needed for now and so ommitted for

        # simplicity.

        bzrlib.xml.serializer_v4.write_inventory(Inventory(), sio)

        dirs = [[], 'text-store', 'inventory-store', 'revision-store']

        files = [('README', 

            "This is a Bazaar-NG control directory.\n"

            "Do not change any files in this directory.\n"),

            ('branch-format', BZR_BRANCH_FORMAT),

            ('revision-history', ''),

            ('merged-patches', ''),

            ('pending-merged-patches', ''),

            ('branch-name', ''),

            ('branch-lock', ''),

            ('pending-merges', ''),

            ('inventory', sio.getvalue())

        ]

        self._transport.mkdir_multi([self._rel_controlfilename(d) for d in dirs])

        self.put_controlfiles(files)

        mutter('created control directory in ' + self._transport.base)

    def _check_format(self):

        """Check this branch format is supported.

        The current tool only supports the current unstable format.

        In the future, we might need different in-memory Branch

        classes to support downlevel branches.  But not yet.

        """

        # This ignores newlines so that we can open branches created

        # on Windows from Linux and so on.  I think it might be better

        # to always make all internal files in unix format.

        fmt = self.controlfile('branch-format', 'r').read()

        fmt = fmt.replace('\r\n', '\n')

        if fmt != BZR_BRANCH_FORMAT:

            raise BzrError('sorry, branch format %r not supported' % fmt,

                           ['use a different bzr version',

                            'or remove the .bzr directory and "bzr init" again'])

        # We know that the format is the currently supported one.

        # So create the rest of the entries.

        from bzrlib.store.compressed_text import CompressedTextStore

        if self._transport.should_cache():

            import tempfile

            self.cache_root = tempfile.mkdtemp(prefix='bzr-cache')

            mutter('Branch %r using caching in %r' % (self, self.cache_root))

        else:

            self.cache_root = None

        def get_store(name):

            relpath = self._rel_controlfilename(name)

            store = CompressedTextStore(self._transport.clone(relpath))

            if self._transport.should_cache():

                from meta_store import CachedStore

                cache_path = os.path.join(self.cache_root, name)

                os.mkdir(cache_path)

                store = CachedStore(store, cache_path)

            return store

        self.text_store = get_store('text-store')

        self.revision_store = get_store('revision-store')

        self.inventory_store = get_store('inventory-store')

    def get_root_id(self):

        """Return the id of this branches root"""

        inv = self.read_working_inventory()

        return inv.root.file_id

    def set_root_id(self, file_id):

        inv = self.read_working_inventory()

        orig_root_id = inv.root.file_id

        del inv._byid[inv.root.file_id]

        inv.root.file_id = file_id

        inv._byid[inv.root.file_id] = inv.root

        for fid in inv:

            entry = inv[fid]

            if entry.parent_id in (None, orig_root_id):

                entry.parent_id = inv.root.file_id

        self._write_inventory(inv)

    def read_working_inventory(self):

        """Read the working inventory."""

        from bzrlib.inventory import Inventory

        self.lock_read()

        try:

            # ElementTree does its own conversion from UTF-8, so open in

            # binary.

            f = self.controlfile('inventory', 'rb')

            return bzrlib.xml.serializer_v4.read_inventory(f)

        finally:

            self.unlock()

    def _write_inventory(self, inv):

        """Update the working inventory.

        That is to say, the inventory describing changes underway, that

        will be committed to the next revision.

        """

        from cStringIO import StringIO

        self.lock_write()

        try:

            sio = StringIO()

            bzrlib.xml.serializer_v4.write_inventory(inv, sio)

            sio.seek(0)

            # Transport handles atomicity

            self.put_controlfile('inventory', sio)

        finally:

            self.unlock()

        mutter('wrote working inventory')

    inventory = property(read_working_inventory, _write_inventory, None,

                         """Inventory for the working copy.""")

    def add(self, files, ids=None):

        """Make files versioned.

        Note that the command line normally calls smart_add instead,

        which can automatically recurse.

        This puts the files in the Added state, so that they will be

        recorded by the next commit.

        files

            List of paths to add, relative to the base of the tree.

        ids

            If set, use these instead of automatically generated ids.

            Must be the same length as the list of files, but may

            contain None for ids that are to be autogenerated.

        TODO: Perhaps have an option to add the ids even if the files do

              not (yet) exist.

        TODO: Perhaps yield the ids and paths as they're added.

        """

        # TODO: Re-adding a file that is removed in the working copy

        # should probably put it back with the previous ID.

        if isinstance(files, basestring):

            assert(ids is None or isinstance(ids, basestring))

            files = [files]

            if ids is not None:

                ids = [ids]

        if ids is None:

            ids = [None] * len(files)

        else:

            assert(len(ids) == len(files))

        self.lock_write()

        try:

            inv = self.read_working_inventory()

            for f,file_id in zip(files, ids):

                if is_control_file(f):

                    raise BzrError("cannot add control file %s" % quotefn(f))

                fp = splitpath(f)

                if len(fp) == 0:

                    raise BzrError("cannot add top-level %r" % f)

                fullpath = os.path.normpath(self.abspath(f))

                try:

                    kind = file_kind(fullpath)

                except OSError:

                    # maybe something better?

                    raise BzrError('cannot add: not a regular file or directory: %s' % quotefn(f))

                if kind != 'file' and kind != 'directory':

                    raise BzrError('cannot add: not a regular file or directory: %s' % quotefn(f))

                if file_id is None:

                    file_id = gen_file_id(f)

                inv.add_path(f, kind=kind, file_id=file_id)

                mutter("add file %s file_id:{%s} kind=%r" % (f, file_id, kind))

            self._write_inventory(inv)

        finally:

            self.unlock()

    def print_file(self, file, revno):

        """Print `file` to stdout."""

        self.lock_read()

        try:

            tree = self.revision_tree(self.lookup_revision(revno))

            # use inventory as it was in that revision

            file_id = tree.inventory.path2id(file)

            if not file_id:

                raise BzrError("%r is not present in revision %s" % (file, revno))

            tree.print_file(file_id)

        finally:

            self.unlock()

    def remove(self, files, verbose=False):

        """Mark nominated files for removal from the inventory.

        This does not remove their text.  This does not run on 

        TODO: Refuse to remove modified files unless --force is given?

        TODO: Do something useful with directories.

        TODO: Should this remove the text or not?  Tough call; not

        removing may be useful and the user can just use use rm, and

        is the opposite of add.  Removing it is consistent with most

        other tools.  Maybe an option.

        """

        ## TODO: Normalize names

        ## TODO: Remove nested loops; better scalability

        if isinstance(files, basestring):

            files = [files]

        self.lock_write()

        try:

            tree = self.working_tree()

            inv = tree.inventory

            # do this before any modifications

            for f in files:

                fid = inv.path2id(f)

                if not fid:

                    raise BzrError("cannot remove unversioned file %s" % quotefn(f))

                mutter("remove inventory entry %s {%s}" % (quotefn(f), fid))

                if verbose:

                    # having remove it, it must be either ignored or unknown

                    if tree.is_ignored(f):

                        new_status = 'I'

                    else:

                        new_status = '?'

                    show_status(new_status, inv[fid].kind, quotefn(f))

                del inv[fid]

            self._write_inventory(inv)

        finally:

            self.unlock()

    # FIXME: this doesn't need to be a branch method

    def set_inventory(self, new_inventory_list):

        from bzrlib.inventory import Inventory, InventoryEntry

        inv = Inventory(self.get_root_id())

        for path, file_id, parent, kind in new_inventory_list:

            name = os.path.basename(path)

            if name == "":

                continue

            inv.add(InventoryEntry(file_id, name, kind, parent))

        self._write_inventory(inv)

    def unknowns(self):

        """Return all unknown files.

        These are files in the working directory that are not versioned or

        control files or ignored.

        >>> b = ScratchBranch(files=['foo', 'foo~'])

        >>> list(b.unknowns())

        ['foo']

        >>> b.add('foo')

        >>> list(b.unknowns())

        []

        >>> b.remove('foo')

        >>> list(b.unknowns())

        ['foo']

        """

        return self.working_tree().unknowns()

    def append_revision(self, *revision_ids):

        for revision_id in revision_ids:

            mutter("add {%s} to revision-history" % revision_id)

        rev_history = self.revision_history()

        rev_history.extend(revision_ids)

        self.lock_write()

        try:

            self.put_controlfile('revision-history', '\n'.join(rev_history))

        finally:

            self.unlock()

    def get_revision_xml_file(self, revision_id):

        """Return XML file object for revision object."""

        if not revision_id or not isinstance(revision_id, basestring):

            raise InvalidRevisionId(revision_id)

        self.lock_read()

        try:

            try:

                return self.revision_store[revision_id]

            except (IndexError, KeyError):

                raise bzrlib.errors.NoSuchRevision(self, revision_id)

        finally:

            self.unlock()

    #deprecated

    get_revision_xml = get_revision_xml_file

    def get_revision(self, revision_id):

        """Return the Revision object for a named revision"""

        xml_file = self.get_revision_xml_file(revision_id)

        try:

            r = bzrlib.xml.serializer_v4.read_revision(xml_file)

        except SyntaxError, e:

            raise bzrlib.errors.BzrError('failed to unpack revision_xml',

                                         [revision_id,

                                          str(e)])

        assert r.revision_id == revision_id

        return r

    def get_revision_delta(self, revno):

        """Return the delta for one revision.

        The delta is relative to its mainline predecessor, or the

        empty tree for revision 1.

        """

        assert isinstance(revno, int)

        rh = self.revision_history()

        if not (1 <= revno <= len(rh)):

            raise InvalidRevisionNumber(revno)

        # revno is 1-based; list is 0-based

        new_tree = self.revision_tree(rh[revno-1])

        if revno == 1:

            old_tree = EmptyTree()

        else:

            old_tree = self.revision_tree(rh[revno-2])

        return compare_trees(old_tree, new_tree)

    def get_revisions(self, revision_ids, pb=None):

        """Return the Revision object for a set of named revisions"""

        from bzrlib.revision import Revision

        from bzrlib.xml import unpack_xml

        # TODO: We need to decide what to do here

        # we cannot use a generator with a try/finally, because

        # you cannot guarantee that the caller will iterate through

        # all entries.

        # in the past, get_inventory wasn't even wrapped in a

        # try/finally locking block.

        # We could either lock without the try/finally, or just

        # not lock at all. We are reading entries that should

        # never be updated.

        # I prefer locking with no finally, so that if someone

        # asks for a list of revisions, but doesn't consume them,

        # that is their problem, and they will suffer the consequences

        self.lock_read()