1 files changed, 111 insertions, 0 deletions
diff --git a/morphlib/plugins/trebuchet_plugin.py b/morphlib/plugins/trebuchet_plugin.py
new file mode 100644
index 00000000..6aa0bc17
--- /dev/null
+++ b/morphlib/plugins/trebuchet_plugin.py
@@ -0,0 +1,111 @@
+# Copyright (C) 2012  Codethink Limited
+#
+# 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; version 2 of the License.
+#
+# 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.
+
+
+import cliapp
+import os
+import tempfile
+
+import morphlib
+
+
+class TrebuchetPlugin(cliapp.Plugin):
+
+    def enable(self):
+        self.app.add_subcommand('make-patch',
+                                self.make_patch,
+                                arg_synopsis='PATH SRC_TRIPLE TGT_TRIPLE')
+
+    def disable(self):
+        pass
+
+    def make_patch(self, args):
+        '''Create a Trebuchet patch between two system images.'''
+
+        if len(args) != 7:
+            raise cliapp.AppException('make-patch requires arguments: '
+                                      'name of output file plus two triplest')
+
+        output = args[0]
+        repo_name1, ref1, filename1 = args[1:4]
+        repo_name2, ref2, filename2 = args[4:7]
+
+        app = self.app
+        build_env = morphlib.buildenvironment.BuildEnvironment(app.settings)
+        ckc = morphlib.cachekeycomputer.CacheKeyComputer(build_env)
+        lac, rac = morphlib.util.new_artifact_caches(app.settings)
+        lrc, rrc = morphlib.util.new_repo_caches(app)
+
+        def the_one(source, repo_name, ref, filename):
+            return (source.repo_name == repo_name and
+                    source.original_ref == ref and
+                    source.filename == filename)
+
+        def get_artifact(repo_name, ref, filename):
+            srcpool = app.create_source_pool(
+                lrc, rrc, (repo_name, ref, filename))
+            ar = morphlib.artifactresolver.ArtifactResolver()
+            artifacts = ar.resolve_artifacts(srcpool)
+            for artifact in artifacts:
+                artifact.cache_key = ckc.compute_key(artifact)
+                if the_one(artifact.source, repo_name, ref, filename):
+                    a = morphlib.artifact.Artifact(
+                        artifact.source,
+                        artifact.source.morphology['name'] + '-rootfs')
+                    a.cache_key = artifact.cache_key
+                    return a
+
+        artifact1 = get_artifact(repo_name1, ref1, filename1)
+        artifact2 = get_artifact(repo_name2, ref2, filename2)
+
+        image_path_1 = lac.get(artifact1).name
+        image_path_2 = lac.get(artifact2).name
+
+        def setup(path):
+            app.status(msg='Mounting image %(path)s', path=path)
+            part = morphlib.fsutils.setup_device_mapping(app.runcmd, path)
+            mount_point = tempfile.mkdtemp(dir=app.settings['tempdir'])
+            morphlib.fsutils.mount(app.runcmd, part, mount_point)
+            return mount_point
+
+        def cleanup(path, mount_point):
+            if mount_point is not None:
+                try:
+                    morphlib.fsutils.unmount(app.runcmd, mount_point)
+                except:
+                    pass
+            try:
+                morphlib.fsutils.undo_device_mapping(app.runcmd, path)
+            except:
+                pass
+            try:
+                os.rmdir(mount_point)
+            except:
+                pass
+
+        mount_point_1 = None
+        mount_point_2 = None
+        try:
+            mount_point_1 = setup(image_path_1)
+            mount_point_2 = setup(image_path_2)
+
+            app.runcmd(['tbdiff-create', output,
+                        os.path.join(mount_point_1, 'factory'),
+                        os.path.join(mount_point_2, 'factory')])
+        except BaseException:
+            raise
+        finally:
+            cleanup(image_path_1, mount_point_1)
+            cleanup(image_path_2, mount_point_2)