~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

## XXX: Can we do any better about making interrupted commits change

## nothing?

## XXX: If we merged two versions of a file then we still need to

## create a new version representing that merge, even if it didn't

## change from the parent.

## TODO: Read back the just-generated changeset, and make sure it

## applies and recreates the right state.

import os

import sys

import time

import tempfile

import sha

from binascii import hexlify

from cStringIO import StringIO

from bzrlib.osutils import (local_time_offset, username,

                            rand_bytes, compact_date, user_email,

                            kind_marker, is_inside_any, quotefn,

                            sha_string, sha_file, isdir, isfile)

from bzrlib.branch import gen_file_id

from bzrlib.errors import BzrError, PointlessCommit

from bzrlib.revision import Revision, RevisionReference

from bzrlib.trace import mutter, note

from bzrlib.xml5 import serializer_v5

from bzrlib.inventory import Inventory

from bzrlib.delta import compare_trees

from bzrlib.weave import Weave

from bzrlib.weavefile import read_weave, write_weave_v5

from bzrlib.atomicfile import AtomicFile

def commit(*args, **kwargs):

    """Commit a new revision to a branch.

    Function-style interface for convenience of old callers.

    New code should use the Commit class instead.

    """

    Commit().commit(*args, **kwargs)

class NullCommitReporter(object):

    """I report on progress of a commit."""

    def added(self, path):

        pass

    def removed(self, path):

        pass

    def renamed(self, old_path, new_path):

        pass

class ReportCommitToLog(NullCommitReporter):

    def added(self, path):

        note('added %s', path)

    def removed(self, path):

        note('removed %s', path)

    def renamed(self, old_path, new_path):

        note('renamed %s => %s', old_path, new_path)

class Commit(object):

    """Task of committing a new revision.

    This is a MethodObject: it accumulates state as the commit is

    prepared, and then it is discarded.  It doesn't represent

    historical revisions, just the act of recording a new one.

            missing_ids

            Modified to hold a list of files that have been deleted from

            the working directory; these should be removed from the

            working inventory.

    """

    def __init__(self,

                 reporter=None):

        if reporter is not None:

            self.reporter = reporter

        else:

            self.reporter = NullCommitReporter()

    def commit(self,

               branch, message,

               timestamp=None,

               timezone=None,

               committer=None,

               specific_files=None,

               rev_id=None,

               allow_pointless=True):

        """Commit working copy as a new revision.

        The basic approach is to add all the file texts into the

        store, then the inventory, then make a new revision pointing

        to that inventory and store that.

        This is not quite safe if the working copy changes during the

        commit; for the moment that is simply not allowed.  A better

        approach is to make a temporary copy of the files before

        computing their hashes, and then add those hashes in turn to

        the inventory.  This should mean at least that there are no

        broken hash pointers.  There is no way we can get a snapshot

        of the whole directory at an instant.  This would also have to

        be robust against files disappearing, moving, etc.  So the

        whole thing is a bit hard.

        This raises PointlessCommit if there are no changes, no new merges,

        and allow_pointless  is false.

        timestamp -- if not None, seconds-since-epoch for a

             postdated/predated commit.

        specific_files

            If true, commit only those files.

        rev_id

            If set, use this as the new revision id.

            Useful for test or import commands that need to tightly

            control what revisions are assigned.  If you duplicate

            a revision id that exists elsewhere it is your own fault.

            If null (default), a time/random revision id is generated.

        """

        self.branch = branch

        self.branch.lock_write()

        self.rev_id = rev_id

        self.specific_files = specific_files

        self.allow_pointless = allow_pointless

        if timestamp is None:

            self.timestamp = time.time()

        else:

            self.timestamp = long(timestamp)

        if committer is None:

            self.committer = username(self.branch)

        else:

            assert isinstance(committer, basestring), type(committer)

            self.committer = committer

        if timezone is None:

            self.timezone = local_time_offset()

        else:

            self.timezone = int(timezone)

        assert isinstance(message, basestring), type(message)

        self.message = message

        try:

            # First walk over the working inventory; and both update that

            # and also build a new revision inventory.  The revision

            # inventory needs to hold the text-id, sha1 and size of the

            # actual file versions committed in the revision.  (These are

            # not present in the working inventory.)  We also need to

            # detect missing/deleted files, and remove them from the

            # working inventory.

            self.work_tree = self.branch.working_tree()

            self.work_inv = self.work_tree.inventory

            self.basis_tree = self.branch.basis_tree()

            self.basis_inv = self.basis_tree.inventory

            self.pending_merges = self.branch.pending_merges()

            if self.pending_merges:

                raise NotImplementedError("sorry, can't commit merges to the weave format yet")

            if self.rev_id is None:

                self.rev_id = _gen_revision_id(self.branch, time.time())

            # todo: update hashcache

            self.delta = compare_trees(self.basis_tree, self.work_tree,

                                       specific_files=self.specific_files)

            if not (self.delta.has_changed()

                    or self.allow_pointless

                    or self.pending_merges):

                raise PointlessCommit()

            self.new_inv = self.basis_inv.copy()

            self.delta.show(sys.stdout)

            self._remove_deleted()

            self._store_files()

            self.branch._write_inventory(self.work_inv)

            self._record_inventory()

            self._make_revision()

            note('committted r%d {%s}', (self.branch.revno() + 1),

                 self.rev_id)

            self.branch.append_revision(self.rev_id)

            self.branch.set_pending_merges([])

        finally:

            self.branch.unlock()

    def _record_inventory(self):

        inv_tmp = StringIO()

        serializer_v5.write_inventory(self.new_inv, inv_tmp)

        self.inv_sha1 = sha_string(inv_tmp.getvalue())

        inv_tmp.seek(0)

        self.branch.inventory_store.add(inv_tmp, self.rev_id)

    def _make_revision(self):

        """Record a new revision object for this commit."""

        self.rev = Revision(timestamp=self.timestamp,

                            timezone=self.timezone,

                            committer=self.committer,

                            message=self.message,

                            inventory_sha1=self.inv_sha1,

                            revision_id=self.rev_id)

        self.rev.parents = []

        precursor_id = self.branch.last_patch()

        if precursor_id:

            self.rev.parents.append(RevisionReference(precursor_id))

        for merge_rev in self.pending_merges:

            rev.parents.append(RevisionReference(merge_rev))

        rev_tmp = tempfile.TemporaryFile()

        serializer_v5.write_revision(self.rev, rev_tmp)

        rev_tmp.seek(0)

        self.branch.revision_store.add(rev_tmp, self.rev_id)

        mutter('new revision_id is {%s}', self.rev_id)

    def _remove_deleted(self):

        """Remove deleted files from the working and stored inventories."""

        for path, id, kind in self.delta.removed:

            if self.work_inv.has_id(id):

                del self.work_inv[id]

            if self.new_inv.has_id(id):

                del self.new_inv[id]

    def _store_files(self):

        """Store new texts of modified/added files."""

        # We must make sure that directories are added before anything

        # inside them is added.  the files within the delta report are

        # sorted by path so we know the directory will come before its

        # contents. 

        for path, file_id, kind in self.delta.added:

            if kind != 'file':

                ie = self.work_inv[file_id].copy()

                self.new_inv.add(ie)

            else:

                self._store_file_text(file_id)

        for path, file_id, kind in self.delta.modified:

            if kind != 'file':

                continue

            self._store_file_text(file_id)

        for old_path, new_path, file_id, kind, text_modified in self.delta.renamed:

            if kind != 'file':

                continue

            if not text_modified:

                continue

            self._store_file_text(file_id)

    def _store_file_text(self, file_id):

        """Store updated text for one modified or added file."""

        note('store new text for {%s} in revision {%s}',

             file_id, self.rev_id)

        new_lines = self.work_tree.get_file(file_id).readlines()

        if file_id in self.new_inv:     # was in basis inventory

            ie = self.new_inv[file_id]

            assert ie.file_id == file_id

            assert file_id in self.basis_inv

            assert self.basis_inv[file_id].kind == 'file'

            old_version = self.basis_inv[file_id].text_version

            file_parents = [old_version]

        else:                           # new in this revision

            ie = self.work_inv[file_id].copy()

            self.new_inv.add(ie)

            assert file_id not in self.basis_inv

            file_parents = []

        assert ie.kind == 'file'

        self._add_text_to_weave(file_id, new_lines, file_parents)

        # make a new inventory entry for this file, using whatever

        # it had in the working copy, plus details on the new text

        ie.text_sha1 = _sha_strings(new_lines)

        ie.text_size = sum(map(len, new_lines))

        ie.text_version = self.rev_id

        ie.entry_version = self.rev_id

    def _add_text_to_weave(self, file_id, new_lines, parents):

        weave_fn = self.branch.controlfilename(['weaves', file_id+'.weave'])

        if os.path.exists(weave_fn):

            w = read_weave(file(weave_fn, 'rb'))

        else:

            w = Weave()

        # XXX: Should set the appropriate parents by looking for this file_id

        # in all revision parents

        parent_idxs = map(w.lookup, parents)

        w.add(self.rev_id, parent_idxs, new_lines)

        af = AtomicFile(weave_fn)

        try:

            write_weave_v5(w, af)

            af.commit()

        finally:

            af.close()

def _gen_revision_id(branch, when):

    """Return new revision-id."""

    s = '%s-%s-' % (user_email(branch), compact_date(when))

    s += hexlify(rand_bytes(8))

    return s

def _sha_strings(strings):

    """Return the sha-1 of concatenation of strings"""

    s = sha.new()

    map(s.update, strings)

    return s.hexdigest()