/brz/remove-bazaar

# Copyright (C) 2018 Jelmer Vernooij <jelmer@jelmer.uk>

#

# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

"""Git Memory Trees."""

from __future__ import absolute_import

import os

import posixpath

import stat

from dulwich.index import (

    index_entry_from_stat,

    )

from dulwich.objects import (

    Blob,

    Tree,

    )

from breezy import (

    errors,

    lock,

    osutils,

    revision as _mod_revision,

    tree as _mod_tree,

    urlutils,

    )

from breezy.transport.memory import MemoryTransport

from .mapping import (

    decode_git_path,

    encode_git_path,

    )

from .tree import MutableGitIndexTree

class GitMemoryTree(MutableGitIndexTree, _mod_tree.Tree):

    """A Git memory tree."""

    def __init__(self, branch, store, head):

        MutableGitIndexTree.__init__(self)

        self.branch = branch

        self.mapping = self.branch.repository.get_mapping()

        self.store = store

        self.index = {}

        self._locks = 0

        self._lock_mode = None

        self._populate_from_branch()

    def _supports_executable(self):

        return True

    @property

    def controldir(self):

        return self.branch.controldir

    def is_control_filename(self, path):

        return False

    def _gather_kinds(self, files, kinds):

        """See MutableTree._gather_kinds.

        """

        with self.lock_tree_write():

            for pos, f in enumerate(files):

                if kinds[pos] is None:

                    kinds[pos] = self.kind(f)

    def put_file_bytes_non_atomic(self, path, bytes):

        """See MutableTree.put_file_bytes_non_atomic."""

        self._file_transport.put_bytes(path, bytes)

    def _populate_from_branch(self):

        """Populate the in-tree state from the branch."""

        if self.branch.head is None:

            self._parent_ids = []

        else:

            self._parent_ids = [self.last_revision()]

        self._file_transport = MemoryTransport()

        if self.branch.head is None:

            tree = Tree()

        else:

            tree_id = self.store[self.branch.head].tree

            tree = self.store[tree_id]

        trees = [("", tree)]

        while trees:

            (path, tree) = trees.pop()

            for name, mode, sha in tree.iteritems():

                subpath = posixpath.join(path, decode_git_path(name))

                if stat.S_ISDIR(mode):

                    self._file_transport.mkdir(subpath)

                    trees.append((subpath, self.store[sha]))

                elif stat.S_ISREG(mode):

                    self._file_transport.put_bytes(

                        subpath, self.store[sha].data)

                    self._index_add_entry(subpath, 'file')

                else:

                    raise NotImplementedError(self._populate_from_branch)

    def lock_read(self):

        """Lock the memory tree for reading.

        This triggers population of data from the branch for its revision.

        """

        self._locks += 1

        try:

            if self._locks == 1:

                self.branch.lock_read()

                self._lock_mode = "r"

                self._populate_from_branch()

            return lock.LogicalLockResult(self.unlock)

        except BaseException:

            self._locks -= 1

            raise

    def lock_tree_write(self):

        """See MutableTree.lock_tree_write()."""

        self._locks += 1

        try:

            if self._locks == 1:

                self.branch.lock_read()

                self._lock_mode = "w"

                self._populate_from_branch()

            elif self._lock_mode == "r":

                raise errors.ReadOnlyError(self)

        except BaseException:

            self._locks -= 1

            raise

        return lock.LogicalLockResult(self.unlock)

    def lock_write(self):

        """See MutableTree.lock_write()."""

        self._locks += 1

        try:

            if self._locks == 1:

                self.branch.lock_write()

                self._lock_mode = "w"

                self._populate_from_branch()

            elif self._lock_mode == "r":

                raise errors.ReadOnlyError(self)

            return lock.LogicalLockResult(self.unlock)

        except BaseException:

            self._locks -= 1

            raise

    def unlock(self):

        """Release a lock.

        This frees all cached state when the last lock context for the tree is

        left.

        """

        if self._locks == 1:

            self._parent_ids = []

            self.index = {}

            try:

                self.branch.unlock()

            finally:

                self._locks = 0

                self._lock_mode = None

        else:

            self._locks -= 1

    def _lstat(self, path):

        mem_stat = self._file_transport.stat(path)

        stat_val = os.stat_result(

            (mem_stat.st_mode, 0, 0, 0, 0, 0, mem_stat.st_size, 0, 0, 0))

        return stat_val

    def _live_entry(self, path):

        path = urlutils.quote_from_bytes(path)

        stat_val = self._lstat(path)

        if stat.S_ISDIR(stat_val.st_mode):

            return None

        elif stat.S_ISLNK(stat_val.st_mode):

            blob = Blob.from_string(

                encode_git_path(self._file_transport.readlink(path)))

        elif stat.S_ISREG(stat_val.st_mode):

            blob = Blob.from_string(self._file_transport.get_bytes(path))

        else:

            raise AssertionError('unknown type %d' % stat_val.st_mode)

        return index_entry_from_stat(stat_val, blob.id, 0)

    def get_file_with_stat(self, path):

        return (self.get_file(path), self._lstat(path))

    def get_file(self, path):

        """See Tree.get_file."""

        return self._file_transport.get(path)

    def get_file_sha1(self, path, stat_value=None):

        """See Tree.get_file_sha1()."""

        stream = self._file_transport.get(path)

        return osutils.sha_file(stream)

    def get_parent_ids(self):

        """See Tree.get_parent_ids.

        This implementation returns the current cached value from

            self._parent_ids.

        """

        with self.lock_read():

            return list(self._parent_ids)

    def last_revision(self):

        """See MutableTree.last_revision."""

        with self.lock_read():

            if self.branch.head is None:

                return _mod_revision.NULL_REVISION

            return self.branch.repository.lookup_foreign_revision_id(

                self.branch.head)

    def basis_tree(self):

        """See Tree.basis_tree()."""

        return self.branch.repository.revision_tree(self.last_revision())

    def get_config_stack(self):

        return self.branch.get_config_stack()

    def has_filename(self, path):

        return self._file_transport.has(path)

    def _set_merges_from_parent_ids(self, rhs_parent_ids):

        if self.branch.head is None:

            self._parent_ids = []

        else:

            self._parent_ids = [self.last_revision()]

        self._parent_ids.extend(rhs_parent_ids)

    def set_parent_ids(self, parent_ids, allow_leftmost_as_ghost=False):

        if len(parent_ids) == 0:

            self._parent_ids = []

            self.branch.head = None

        else:

            self._parent_ids = parent_ids

            self.branch.head = self.branch.repository.lookup_bzr_revision_id(

                parent_ids[0])[0]

    def mkdir(self, path, file_id=None):

        """See MutableTree.mkdir()."""

        self.add(path, None, 'directory')

        self._file_transport.mkdir(path)

    def _rename_one(self, from_rel, to_rel):

        self._file_transport.rename(from_rel, to_rel)

    def kind(self, p):

        stat_value = self._file_transport.stat(p)

        return osutils.file_kind_from_stat_mode(stat_value.st_mode)

    def get_symlink_target(self, path):

        with self.lock_read():

            return self._file_transport.readlink(path)