tests/functional: move archive handling into new archive.py file

More archive related code will be added shortly, so having a
separate file makes more sense.

The utils.py imports the functions from archive.py, so that
existing callers don't need to be modified. This avoids
redundant code churn until later in the series when all
calls will be adapted for other reasons.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-ID: <20241217155953.3950506-17-berrange@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

tests/functional/qemu_test/archive.py

@@ -0,0 +1,31 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
+# Utilities for python-based QEMU tests
+#
+# Copyright 2024 Red Hat, Inc.
+#
+# Authors:
+#  Thomas Huth <thuth@redhat.com>
+
+import os
+import subprocess
+import tarfile
+
+
+def tar_extract(archive, dest_dir, member=None):
+    with tarfile.open(archive) as tf:
+        if hasattr(tarfile, 'data_filter'):
+            tf.extraction_filter = getattr(tarfile, 'data_filter',
+                                           (lambda member, path: member))
+        if member:
+            tf.extract(member=member, path=dest_dir)
+        else:
+            tf.extractall(path=dest_dir)
+
+def cpio_extract(cpio_handle, output_path):
+    cwd = os.getcwd()
+    os.chdir(output_path)
+    subprocess.run(['cpio', '-i'],
+                   input=cpio_handle.read(),
+                   stderr=subprocess.DEVNULL)
+    os.chdir(cwd)

tests/functional/qemu_test/utils.py

@@ -12,8 +12,9 @@ import gzip
 import lzma
 import os
 import shutil
-import subprocess
+
-import tarfile
+from .archive import tar_extract as archive_extract
+from .archive import cpio_extract
 
 """
 Round up to next power of 2
@@ -36,16 +37,6 @@ def image_pow2ceil_expand(path):
             with open(path, 'ab+') as fd:
                 fd.truncate(size_aligned)
 
-def archive_extract(archive, dest_dir, member=None):
-    with tarfile.open(archive) as tf:
-        if hasattr(tarfile, 'data_filter'):
-            tf.extraction_filter = getattr(tarfile, 'data_filter',
-                                           (lambda member, path: member))
-        if member:
-            tf.extract(member=member, path=dest_dir)
-        else:
-            tf.extractall(path=dest_dir)
-
 def gzip_uncompress(gz_path, output_path):
     if os.path.exists(output_path):
         return
@@ -67,11 +58,3 @@ def lzma_uncompress(xz_path, output_path):
         except:
             os.remove(output_path)
             raise
-
-def cpio_extract(cpio_handle, output_path):
-    cwd = os.getcwd()
-    os.chdir(output_path)
-    subprocess.run(['cpio', '-i'],
-                   input=cpio_handle.read(),
-                   stderr=subprocess.DEVNULL)
-    os.chdir(cwd)