#!/usr/bin/python -u
# vim: set fileencoding=utf-8 :
#
# (C) 2006, 2007, 2009 Guido Guenther <agx@sigxcpu.org>
#    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 a new upstream version into a git repository"""

import sys
import os
import tempfile
import re
import glob
import subprocess
import tarfile
import time
import gbp.command_wrappers as gbpc
from gbp.deb_utils import parse_changelog, unpack_orig, repack_orig, NoChangelogError, has_epoch, tar_toplevel, guess_upstream_version
from gbp.git_utils import (GitRepositoryError, GitRepository, build_tag)
from gbp.config import GbpOptionParser
from gbp.errors import (GbpError, GbpNothingImported)

class FastImport(object):
    """Invoke git-fast-import"""
    _bufsize = 1024

    m_regular = 644
    m_exec    = 755
    m_symlink = 120000

    def __init__(self):
        try:
            self._fi = subprocess.Popen([ 'git', 'fast-import', '--quiet'], stdin=subprocess.PIPE)
            self._out = self._fi.stdin
        except OSError, err:
            raise GbpError, "Error spawning git fast-import: %s", err
        except ValueError, err:
            raise GbpError, "Invalid argument when spawning git fast-import: %s", err

    def _do_data(self, fd, size):
        self._out.write("data %s\n" % size)
        while True:
            data = fd.read(self._bufsize)
            self._out.write(data)
            if len(data) != self._bufsize:
                break
        self._out.write("\n")

    def _do_file(self, filename, mode, fd, size):
        name = "/".join(filename.split('/')[1:])
        self._out.write("M %d inline %s\n" % (mode, name))
        self._do_data(fd, size)

    def add_file(self, filename, fd, size):
        self._do_file(filename, self.m_regular, fd, size)

    def add_executable(self, filename, fd, size):
        self._do_file(filename, self.m_exec, fd, size)

    def add_symlink(self, filename, linkname):
        name = "/".join(filename.split('/')[1:])
        self._out.write("M %d inline %s\n" % (self.m_symlink, name))
        self._out.write("data %s\n" % len(linkname))
        self._out.write("%s\n" % linkname)

    def start_commit(self, branch, committer, email, time, msg):
        length = len(msg)
        self._out.write("""commit refs/heads/%(branch)s
committer %(committer)s <%(email)s> %(time)s
data %(length)s
%(msg)s
from refs/heads/%(branch)s^0
""" % locals())

    def do_deleteall(self):
        self._out.write("deleteall\n")

    def close(self):
        if self._out:
            self._out.close()
        if self._fi:
            self._fi.wait()

    def __del__(self):
        self.close()


def cleanup_tmp_tree(tree):
    """remove a tree of temporary files"""
    try:
        gbpc.RemoveTree(tree)()
    except gbpc.CommandExecFailed:
        print >>sys.stderr, "Removal of tmptree %s failed." % tree


def is_link_target(target, link):
    """does symlink link already point to target?"""
    if os.path.exists(link):
            if os.path.samefile(target, link):
                return True
    return False


def symlink_orig(archive, pkg, version):
    """
    create a symlink <pkg>_<version>.orig.tar.gz so pristine-tar will see the
    correct basename
    @return: archive path to be used by pristine tar
    """
    if os.path.isdir(archive):
        return None
    ext = os.path.splitext(archive)[1]
    link = "../%s_%s.orig.tar%s" % (pkg, version, ext)
    if os.path.basename(archive) != os.path.basename(link):
        try:
            if not is_link_target(archive, link):
                os.symlink(os.path.abspath(archive), link)
        except OSError, err:
                raise GbpError, "Cannot symlink '%s' to '%s': %s" % (archive, link, err[1])
        return link
    else:
        return archive


def upstream_import_commit_msg(version):
    return "Imported Upstream version %s" % version


def import_upstream_tree(repo, src_dir, version, filters, verbose):
    """import the upstream tree to the current branch"""
    try:
        if repo.replace_tree(src_dir, filters, verbose=True):
            gbpc.GitCommitAll(verbose=verbose)(msg=upstream_import_commit_msg(version))
        else:
            raise GbpNothingImported
    except gbpc.CommandExecFailed:
        raise GbpError, "Import of upstream version %s failed." % version


def fast_import_upstream_tree(repo, tarball, version, options):
    """import the upstream tree to the current branch using git fast-import"""

    try:
        compr = tarball.split('.')[-1]

        if not tarfile.is_tarfile(tarball):
            raise GbpError, "'%s' not a tarball" % tarball 

        tar = tarfile.open(tarball, "r:%s" % compr)

        now = "%d %s" % (time.time(), time.strftime("%z"))
        fastimport = FastImport()
        name, email = repo.get_author_info()
        if options.verbose:
            print "Starting fastimport of %s" % tarball
        fastimport.start_commit(options.upstream_branch, name, email, now,
                                upstream_import_commit_msg(version))
        fastimport.do_deleteall()

        for item in tar:
            if item.isfile():
                if item.mode & 0100:
                    fastimport.add_executable(item.name, tar.extractfile(item.name), item.size)
                else:
                    fastimport.add_file(item.name, tar.extractfile(item.name), item.size)
            elif item.isdir():
                continue # handled by git transparently
            elif item.issym():
                fastimport.add_symlink(item.name, item.linkname)
            # if tarinfo.isextended() not implemented:
            elif item.type in ( "x", "g", "X" ):
                if options.verbose:
                    print "Skipping %s of type '%s'" % (item.name, item.type)
                continue
            else:
                raise GbpError, "'%s' is not a regular file (%s) - don't use fastimport." % (item.name, item.type)
    except gbpc.CommandExecFailed:
        raise GbpError, "Fastimport of upstream version %s failed." % version
    finally:
        tar.close()
        fastimport.close()

    if options.verbose:
        print "FastImport done."


def turn_off_fastimport(options, msg):
    if options.fast_import:
        print >>sys.stderr, msg
        print >>sys.stderr, "Turning off fastimport."
        options.fast_import = False


def main(argv):
    ret = 0
    tmpdir = ''
    pristine_orig = None

    parser = GbpOptionParser(command=os.path.basename(argv[0]), prefix='',
                           usage='%prog [-u version] /path/to/upstream-version.tar.gz')

    parser.add_option("-u", "--upstream-version", dest="version",
                      help="Upstream Version")
    parser.add_option("-v", "--verbose", action="store_true", dest="verbose", default=False,
                      help="verbose command execution")
    parser.add_option("--fast-import", action="store_true", dest="fast_import", default=False,
                      help="use 'git fastimport' (experimental)")
    parser.add_config_file_option(option_name="debian-branch", dest="debian_branch")
    parser.add_config_file_option(option_name="upstream-branch", dest="upstream_branch")
    parser.add_option("--no-merge", dest='merge', action="store_false", default=True,
                      help="after import dont do any merging to another branch")
    parser.add_config_file_option(option_name="no-dch", dest='no_dch',
                      help="don't call dch after the import", action="store_true")
    parser.add_boolean_config_file_option(option_name="sign-tags", dest="sign_tags")
    parser.add_config_file_option(option_name="keyid", dest="keyid")
    parser.add_config_file_option(option_name="upstream-tag", dest="upstream_tag")
    parser.add_config_file_option(option_name="filter", dest="filters", action="append")
    parser.add_boolean_config_file_option(option_name="pristine-tar", dest="pristine_tar")
    parser.add_boolean_config_file_option(option_name="filter-pristine-tar", dest="filter_pristine_tar")
    (options, args) = parser.parse_args(argv[1:])

    if options.verbose:
        gbpc.Command.verbose = True

    if options.filters:
        turn_off_fastimport(options, "Import filters currently not supported with fastimport.")

    try:
        if len(args) != 1:
            parser.print_help()
            raise GbpError
        else:
            archive = args[0]

        try:
            repo = GitRepository('.')
        except GitRepositoryError:
            raise GbpError, "%s is not a git repository" % (os.path.abspath('.'))

        # an empty repo has now branches:
        initial_branch = repo.get_branch()
        if initial_branch:
            is_empty = False
        else:
            is_empty = True
            turn_off_fastimport(options, "Fast importing into empty archives not yet supported.")

        if not repo.has_branch(options.upstream_branch) and not is_empty:
            print >>sys.stderr, """
Repository does not have branch '%s' for upstream sources. If there is none see
file:///usr/share/doc/git-buildpackage/manual-html/gbp.import.html#GBP.IMPORT.CONVERT
on howto create it otherwise use --upstream-branch to specify it.
"""  % options.upstream_branch
            raise GbpError

        if options.version:
            version = options.version
        else:
            version = guess_upstream_version(archive)

        if version:
            print "Upstream version is %s" % version
        else:
            print >>sys.stderr, "Cannot determine upstream version from %s - use -u <version>" % archive
            parser.print_help()
            raise GbpError

        (clean, out) = repo.is_clean()
        if not clean and not is_empty:
            print >>sys.stderr, "Repository has uncommitted changes, commit these first: "
            raise GbpError, out

        if os.path.isdir(archive):
            orig_dir = archive
            turn_off_fastimport(options, "Fastimport only supported for tar achives.")

        else:
            if not options.fast_import:
                tmpdir = tempfile.mkdtemp(dir='../')
                unpack_orig(archive, tmpdir, options.filters)
                if options.verbose:
                    print "Unpacked %s to '%s'" % (archive , tmpdir)
                orig_dir = tar_toplevel(tmpdir)
                if options.pristine_tar and options.filter_pristine_tar and len(options.filters) > 0:
                    if options.verbose:
                        print "Filter pristine-tar: repacking %s from '%s'" % (archive, tmpdir)
                    archive = os.path.join(
                        os.path.dirname(archive),
                        os.path.basename(archive).replace(".tar", ".gbp.tar")
                        )
                    repack_orig(archive, tmpdir, os.path.basename(orig_dir))
            try:
                cp = parse_changelog('debian/changelog')
                pristine_orig = symlink_orig(archive, cp['Source'], version)
            except NoChangelogError:
                print "Warning: Can't symlink orig.tar.gz due to missing debian/changelog"
                pristine_orig = archive

        try:
            filter_msg = ["", " (filtering out %s)" % options.filters][len(options.filters) > 0]
            if is_empty:
                print "Initial import of '%s' %s..." % (archive, filter_msg)
            else:
                print "Importing '%s' to branch '%s'%s..." % (archive, options.upstream_branch, filter_msg)
                if not options.fast_import:
                    repo.set_branch(options.upstream_branch)

            if options.fast_import:
                fast_import_upstream_tree(repo, pristine_orig, version, options)
            else:
                import_upstream_tree(repo, orig_dir, version, options.filters, verbose=not is_empty)

            if options.pristine_tar:
                upstream_branch = [ options.upstream_branch, 'master' ][is_empty]
                if pristine_orig:
                    gbpc.PristineTar().commit(pristine_orig, 'refs/heads/%s' % upstream_branch)
                else:
                    print >>sys.stderr, "Warning: '%s' not an archive, skipping pristine-tar" % archive
            tag = build_tag(options.upstream_tag, version)
            gbpc.GitTag(options.sign_tags, options.keyid)(tag,
                                                          msg="Upstream version %s" % version,
                                                          commit=[None, options.upstream_branch][options.fast_import])

            if is_empty:
                gbpc.GitBranch()(options.upstream_branch)
            elif options.merge:
                print "Merging to '%s'" % options.debian_branch
                repo.set_branch(options.debian_branch)
                try:
                    gbpc.GitMerge(tag)()
                except gbpc.CommandExecFailed:
                    raise GbpError, """Merge failed, please resolve and run "dch -v %s-1".""" % version
                if not options.no_dch:
                    epoch = ''
                    if os.access('debian/changelog', os.R_OK):
                        cp = parse_changelog('debian/changelog')
                        if has_epoch(cp):
                            epoch = '%s:' % cp['Epoch']
                    gbpc.Dch("%s%s-1" % (epoch, version), 'New Upstream Version')()
        except gbpc.CommandExecFailed:
            raise GbpError, "Import of %s failed" % archive
    except GbpNothingImported, err:
        print >>sys.stderr, err
        repo.set_branch(initial_branch)
        ret = 1
    except GbpError, err:
        if len(err.__str__()):
            print >>sys.stderr, err
        ret = 1

    if tmpdir:
        cleanup_tmp_tree(tmpdir)

    if not ret:
        print "Succesfully merged version %s of %s into ." % (version, archive)
    return ret

if __name__ == "__main__":
    sys.exit(main(sys.argv))

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