1 files changed, 66 insertions, 0 deletions
diff --git a/linaro_image_tools/hwpack/package_unpacker.py b/linaro_image_tools/hwpack/package_unpacker.py
new file mode 100644
index 0000000..b976abf
--- /dev/null
+++ b/linaro_image_tools/hwpack/package_unpacker.py
@@ -0,0 +1,66 @@
+# Copyright (C) 2010, 2011, 2013 Linaro
+#
+# This file is part of Linaro Image Tools.
+#
+# Linaro Image Tools 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.
+#
+# Linaro Image Tools 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 Linaro Image Tools; if not, write to the Free Software
+# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301,
+# USA.
+
+import logging
+import os
+import tempfile
+
+from subprocess import PIPE
+from shutil import rmtree
+
+from linaro_image_tools import cmd_runner
+
+logger = logging.getLogger(__name__)
+
+
+class PackageUnpacker(object):
+    def __enter__(self):
+        self.tempdir = tempfile.mkdtemp()
+        return self
+
+    def __exit__(self, type, value, traceback):
+        if self.tempdir is not None and os.path.exists(self.tempdir):
+            rmtree(self.tempdir)
+
+    def get_path(self, package_file_name, file_name=''):
+        """Get package or file path in unpacker tmp dir."""
+        package_dir = os.path.basename(package_file_name)
+        return os.path.join(self.tempdir, package_dir, file_name)
+
+    def unpack_package(self, package_file_name):
+        # We could extract only a single file, but since dpkg will pipe
+        # the entire package through tar anyway we might as well extract all.
+        unpack_dir = self.get_path(package_file_name)
+        if not os.path.isdir(unpack_dir):
+            os.mkdir(unpack_dir)
+        p = cmd_runner.run(["tar", "-C", unpack_dir, "-xf", "-"], stdin=PIPE)
+        cmd_runner.run(["dpkg", "--fsys-tarfile", package_file_name],
+                       stdout=p.stdin).communicate()
+        p.communicate()
+
+    def get_file(self, package, file):
+        # File path passed here must not be absolute, or file from
+        # real filesystem will be referenced.
+        assert file and file[0] != '/'
+        self.unpack_package(package)
+        logger.debug("Unpacked package %s." % package)
+        temp_file = self.get_path(package, file)
+        assert os.path.exists(temp_file), "The file '%s' was " \
+            "not found in the package '%s'." % (file, package)
+        return temp_file